diff options
Diffstat (limited to 'drivers/i2c')
29 files changed, 2376 insertions, 313 deletions
diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig index d06083fdffbb..b923074b2cbe 100644 --- a/drivers/i2c/Kconfig +++ b/drivers/i2c/Kconfig @@ -47,6 +47,19 @@ config I2C_CHARDEV This support is also available as a module. If so, the module will be called i2c-dev. +config I2C_MUX + tristate "I2C bus multiplexing support" + depends on EXPERIMENTAL + help + Say Y here if you want the I2C core to support the ability to + handle multiplexed I2C bus topologies, by presenting each + multiplexed segment as a I2C adapter. + + This support is also available as a module. If so, the module + will be called i2c-mux. + +source drivers/i2c/muxes/Kconfig + config I2C_HELPER_AUTO bool "Autoselect pertinent helper modules" default y @@ -62,7 +75,8 @@ config I2C_HELPER_AUTO In doubt, say Y. config I2C_SMBUS - tristate "SMBus-specific protocols" if !I2C_HELPER_AUTO + tristate + prompt "SMBus-specific protocols" if !I2C_HELPER_AUTO help Say Y here if you want support for SMBus extensions to the I2C specification. At the moment, the only supported extension is diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile index a7d9b4be9bb3..23ac61e2db39 100644 --- a/drivers/i2c/Makefile +++ b/drivers/i2c/Makefile @@ -6,8 +6,7 @@ obj-$(CONFIG_I2C_BOARDINFO) += i2c-boardinfo.o obj-$(CONFIG_I2C) += i2c-core.o obj-$(CONFIG_I2C_SMBUS) += i2c-smbus.o obj-$(CONFIG_I2C_CHARDEV) += i2c-dev.o -obj-y += algos/ busses/ +obj-$(CONFIG_I2C_MUX) += i2c-mux.o +obj-y += algos/ busses/ muxes/ -ifeq ($(CONFIG_I2C_DEBUG_CORE),y) -EXTRA_CFLAGS += -DDEBUG -endif +ccflags-$(CONFIG_I2C_DEBUG_CORE) := -DDEBUG diff --git a/drivers/i2c/algos/Kconfig b/drivers/i2c/algos/Kconfig index 7b2ce4a08524..3998dd620a03 100644 --- a/drivers/i2c/algos/Kconfig +++ b/drivers/i2c/algos/Kconfig @@ -15,3 +15,15 @@ config I2C_ALGOPCA tristate "I2C PCA 9564 interfaces" endmenu + +# In automatic configuration mode, we still have to define the +# symbols to avoid unmet dependencies. + +if I2C_HELPER_AUTO +config I2C_ALGOBIT + tristate +config I2C_ALGOPCF + tristate +config I2C_ALGOPCA + tristate +endif diff --git a/drivers/i2c/algos/Makefile b/drivers/i2c/algos/Makefile index 18b3e962ec09..215303f60d61 100644 --- a/drivers/i2c/algos/Makefile +++ b/drivers/i2c/algos/Makefile @@ -6,6 +6,4 @@ obj-$(CONFIG_I2C_ALGOBIT) += i2c-algo-bit.o obj-$(CONFIG_I2C_ALGOPCF) += i2c-algo-pcf.o obj-$(CONFIG_I2C_ALGOPCA) += i2c-algo-pca.o -ifeq ($(CONFIG_I2C_DEBUG_ALGO),y) -EXTRA_CFLAGS += -DDEBUG -endif +ccflags-$(CONFIG_I2C_DEBUG_ALGO) := -DDEBUG diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index bceafbfa7268..6539ac2907e9 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -448,6 +448,13 @@ config I2C_NOMADIK If you say yes to this option, support will be included for the I2C interface from ST-Ericsson's Nomadik and Ux500 architectures. +config I2C_NUC900 + tristate "NUC900 I2C Driver" + depends on ARCH_W90X900 + help + Say Y here to include support for I2C controller in the + Winbond/Nuvoton NUC900 based System-on-Chip devices. + config I2C_OCORES tristate "OpenCores I2C Controller" depends on EXPERIMENTAL @@ -496,8 +503,8 @@ config I2C_PMCMSP will be called i2c-pmcmsp. config I2C_PNX - tristate "I2C bus support for Philips PNX targets" - depends on ARCH_PNX4008 + tristate "I2C bus support for Philips PNX and NXP LPC targets" + depends on ARCH_PNX4008 || ARCH_LPC32XX help This driver supports the Philips IP3204 I2C IP block master and/or slave controller @@ -521,12 +528,19 @@ config I2C_PXA_SLAVE is necessary for systems where the PXA may be a target on the I2C bus. +config HAVE_S3C2410_I2C + bool + help + This will include I2C support for Samsung SoCs. If you want to + include I2C support for any machine, kindly select this in the + respective Kconfig file. + config I2C_S3C2410 tristate "S3C2410 I2C Driver" - depends on ARCH_S3C2410 || ARCH_S3C64XX + depends on HAVE_S3C2410_I2C help Say Y here to include support for I2C controller in the - Samsung S3C2410 based System-on-Chip devices. + Samsung SoCs. config I2C_S6000 tristate "S6000 I2C support" @@ -549,7 +563,7 @@ config I2C_SH7760 config I2C_SH_MOBILE tristate "SuperH Mobile I2C Controller" - depends on SUPERH + depends on SUPERH || ARCH_SHMOBILE help If you say yes to this option, support will be included for the built-in I2C interface on the Renesas SH-Mobile processor. diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 936880bd1dc5..033ad413f328 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -43,6 +43,7 @@ obj-$(CONFIG_I2C_IXP2000) += i2c-ixp2000.o obj-$(CONFIG_I2C_MPC) += i2c-mpc.o obj-$(CONFIG_I2C_MV64XXX) += i2c-mv64xxx.o obj-$(CONFIG_I2C_NOMADIK) += i2c-nomadik.o +obj-$(CONFIG_I2C_NUC900) += i2c-nuc900.o obj-$(CONFIG_I2C_OCORES) += i2c-ocores.o obj-$(CONFIG_I2C_OMAP) += i2c-omap.o obj-$(CONFIG_I2C_PASEMI) += i2c-pasemi.o @@ -75,6 +76,4 @@ obj-$(CONFIG_I2C_STUB) += i2c-stub.o obj-$(CONFIG_SCx200_ACB) += scx200_acb.o obj-$(CONFIG_SCx200_I2C) += scx200_i2c.o -ifeq ($(CONFIG_I2C_DEBUG_BUS),y) -EXTRA_CFLAGS += -DDEBUG -endif +ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG diff --git a/drivers/i2c/busses/i2c-amd8111.c b/drivers/i2c/busses/i2c-amd8111.c index af1e5e254b7b..6b6a6b1d7025 100644 --- a/drivers/i2c/busses/i2c-amd8111.c +++ b/drivers/i2c/busses/i2c-amd8111.c @@ -69,7 +69,7 @@ static struct pci_driver amd8111_driver; * ACPI 2.0 chapter 13 access of registers of the EC */ -static unsigned int amd_ec_wait_write(struct amd_smbus *smbus) +static int amd_ec_wait_write(struct amd_smbus *smbus) { int timeout = 500; @@ -85,7 +85,7 @@ static unsigned int amd_ec_wait_write(struct amd_smbus *smbus) return 0; } -static unsigned int amd_ec_wait_read(struct amd_smbus *smbus) +static int amd_ec_wait_read(struct amd_smbus *smbus) { int timeout = 500; @@ -101,7 +101,7 @@ static unsigned int amd_ec_wait_read(struct amd_smbus *smbus) return 0; } -static unsigned int amd_ec_read(struct amd_smbus *smbus, unsigned char address, +static int amd_ec_read(struct amd_smbus *smbus, unsigned char address, unsigned char *data) { int status; @@ -124,7 +124,7 @@ static unsigned int amd_ec_read(struct amd_smbus *smbus, unsigned char address, return 0; } -static unsigned int amd_ec_write(struct amd_smbus *smbus, unsigned char address, +static int amd_ec_write(struct amd_smbus *smbus, unsigned char address, unsigned char data) { int status; @@ -196,7 +196,7 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr, { struct amd_smbus *smbus = adap->algo_data; unsigned char protocol, len, pec, temp[2]; - int i; + int i, status; protocol = (read_write == I2C_SMBUS_READ) ? AMD_SMB_PRTCL_READ : AMD_SMB_PRTCL_WRITE; @@ -209,38 +209,62 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr, break; case I2C_SMBUS_BYTE: - if (read_write == I2C_SMBUS_WRITE) - amd_ec_write(smbus, AMD_SMB_CMD, command); + if (read_write == I2C_SMBUS_WRITE) { + status = amd_ec_write(smbus, AMD_SMB_CMD, + command); + if (status) + return status; + } protocol |= AMD_SMB_PRTCL_BYTE; break; case I2C_SMBUS_BYTE_DATA: - amd_ec_write(smbus, AMD_SMB_CMD, command); - if (read_write == I2C_SMBUS_WRITE) - amd_ec_write(smbus, AMD_SMB_DATA, data->byte); + status = amd_ec_write(smbus, AMD_SMB_CMD, command); + if (status) + return status; + if (read_write == I2C_SMBUS_WRITE) { + status = amd_ec_write(smbus, AMD_SMB_DATA, + data->byte); + if (status) + return status; + } protocol |= AMD_SMB_PRTCL_BYTE_DATA; break; case I2C_SMBUS_WORD_DATA: - amd_ec_write(smbus, AMD_SMB_CMD, command); + status = amd_ec_write(smbus, AMD_SMB_CMD, command); + if (status) + return status; if (read_write == I2C_SMBUS_WRITE) { - amd_ec_write(smbus, AMD_SMB_DATA, - data->word & 0xff); - amd_ec_write(smbus, AMD_SMB_DATA + 1, - data->word >> 8); + status = amd_ec_write(smbus, AMD_SMB_DATA, + data->word & 0xff); + if (status) + return status; + status = amd_ec_write(smbus, AMD_SMB_DATA + 1, + data->word >> 8); + if (status) + return status; } protocol |= AMD_SMB_PRTCL_WORD_DATA | pec; break; case I2C_SMBUS_BLOCK_DATA: - amd_ec_write(smbus, AMD_SMB_CMD, command); + status = amd_ec_write(smbus, AMD_SMB_CMD, command); + if (status) + return status; if (read_write == I2C_SMBUS_WRITE) { len = min_t(u8, data->block[0], I2C_SMBUS_BLOCK_MAX); - amd_ec_write(smbus, AMD_SMB_BCNT, len); - for (i = 0; i < len; i++) - amd_ec_write(smbus, AMD_SMB_DATA + i, - data->block[i + 1]); + status = amd_ec_write(smbus, AMD_SMB_BCNT, len); + if (status) + return status; + for (i = 0; i < len; i++) { + status = + amd_ec_write(smbus, AMD_SMB_DATA + i, + data->block[i + 1]); + if (status) + return status; + } } protocol |= AMD_SMB_PRTCL_BLOCK_DATA | pec; break; @@ -248,19 +272,35 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr, case I2C_SMBUS_I2C_BLOCK_DATA: len = min_t(u8, data->block[0], I2C_SMBUS_BLOCK_MAX); - amd_ec_write(smbus, AMD_SMB_CMD, command); - amd_ec_write(smbus, AMD_SMB_BCNT, len); + status = amd_ec_write(smbus, AMD_SMB_CMD, command); + if (status) + return status; + status = amd_ec_write(smbus, AMD_SMB_BCNT, len); + if (status) + return status; if (read_write == I2C_SMBUS_WRITE) - for (i = 0; i < len; i++) - amd_ec_write(smbus, AMD_SMB_DATA + i, - data->block[i + 1]); + for (i = 0; i < len; i++) { + status = + amd_ec_write(smbus, AMD_SMB_DATA + i, + data->block[i + 1]); + if (status) + return status; + } protocol |= AMD_SMB_PRTCL_I2C_BLOCK_DATA; break; case I2C_SMBUS_PROC_CALL: - amd_ec_write(smbus, AMD_SMB_CMD, command); - amd_ec_write(smbus, AMD_SMB_DATA, data->word & 0xff); - amd_ec_write(smbus, AMD_SMB_DATA + 1, data->word >> 8); + status = amd_ec_write(smbus, AMD_SMB_CMD, command); + if (status) + return status; + status = amd_ec_write(smbus, AMD_SMB_DATA, + data->word & 0xff); + if (status) + return status; + status = amd_ec_write(smbus, AMD_SMB_DATA + 1, + data->word >> 8); + if (status) + return status; protocol = AMD_SMB_PRTCL_PROC_CALL | pec; read_write = I2C_SMBUS_READ; break; @@ -268,11 +308,18 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr, case I2C_SMBUS_BLOCK_PROC_CALL: len = min_t(u8, data->block[0], I2C_SMBUS_BLOCK_MAX - 1); - amd_ec_write(smbus, AMD_SMB_CMD, command); - amd_ec_write(smbus, AMD_SMB_BCNT, len); - for (i = 0; i < len; i++) - amd_ec_write(smbus, AMD_SMB_DATA + i, - data->block[i + 1]); + status = amd_ec_write(smbus, AMD_SMB_CMD, command); + if (status) + return status; + status = amd_ec_write(smbus, AMD_SMB_BCNT, len); + if (status) + return status; + for (i = 0; i < len; i++) { + status = amd_ec_write(smbus, AMD_SMB_DATA + i, + data->block[i + 1]); + if (status) + return status; + } protocol = AMD_SMB_PRTCL_BLOCK_PROC_CALL | pec; read_write = I2C_SMBUS_READ; break; @@ -282,24 +329,29 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr, return -EOPNOTSUPP; } - amd_ec_write(smbus, AMD_SMB_ADDR, addr << 1); - amd_ec_write(smbus, AMD_SMB_PRTCL, protocol); + status = amd_ec_write(smbus, AMD_SMB_ADDR, addr << 1); + if (status) + return status; + status = amd_ec_write(smbus, AMD_SMB_PRTCL, protocol); + if (status) + return status; - /* FIXME this discards status from ec_read(); so temp[0] will - * hold stack garbage ... the rest of this routine will act - * nonsensically. Ignored ec_write() status might explain - * some such failures... - */ - amd_ec_read(smbus, AMD_SMB_STS, temp + 0); + status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0); + if (status) + return status; if (~temp[0] & AMD_SMB_STS_DONE) { udelay(500); - amd_ec_read(smbus, AMD_SMB_STS, temp + 0); + status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0); + if (status) + return status; } if (~temp[0] & AMD_SMB_STS_DONE) { msleep(1); - amd_ec_read(smbus, AMD_SMB_STS, temp + 0); + status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0); + if (status) + return status; } if ((~temp[0] & AMD_SMB_STS_DONE) || (temp[0] & AMD_SMB_STS_STATUS)) @@ -311,24 +363,35 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr, switch (size) { case I2C_SMBUS_BYTE: case I2C_SMBUS_BYTE_DATA: - amd_ec_read(smbus, AMD_SMB_DATA, &data->byte); + status = amd_ec_read(smbus, AMD_SMB_DATA, &data->byte); + if (status) + return status; break; case I2C_SMBUS_WORD_DATA: case I2C_SMBUS_PROC_CALL: - amd_ec_read(smbus, AMD_SMB_DATA, temp + 0); - amd_ec_read(smbus, AMD_SMB_DATA + 1, temp + 1); + status = amd_ec_read(smbus, AMD_SMB_DATA, temp + 0); + if (status) + return status; + status = amd_ec_read(smbus, AMD_SMB_DATA + 1, temp + 1); + if (status) + return status; data->word = (temp[1] << 8) | temp[0]; break; case I2C_SMBUS_BLOCK_DATA: case I2C_SMBUS_BLOCK_PROC_CALL: - amd_ec_read(smbus, AMD_SMB_BCNT, &len); + status = amd_ec_read(smbus, AMD_SMB_BCNT, &len); + if (status) + return status; len = min_t(u8, len, I2C_SMBUS_BLOCK_MAX); case I2C_SMBUS_I2C_BLOCK_DATA: - for (i = 0; i < len; i++) - amd_ec_read(smbus, AMD_SMB_DATA + i, - data->block + i + 1); + for (i = 0; i < len; i++) { + status = amd_ec_read(smbus, AMD_SMB_DATA + i, + data->block + i + 1); + if (status) + return status; + } data->block[0] = len; break; } diff --git a/drivers/i2c/busses/i2c-cpm.c b/drivers/i2c/busses/i2c-cpm.c index e591de1bc704..f2de3be35df3 100644 --- a/drivers/i2c/busses/i2c-cpm.c +++ b/drivers/i2c/busses/i2c-cpm.c @@ -105,7 +105,7 @@ struct i2c_reg { struct cpm_i2c { char *base; - struct of_device *ofdev; + struct platform_device *ofdev; struct i2c_adapter adap; uint dp_addr; int version; /* CPM1=1, CPM2=2 */ @@ -428,7 +428,7 @@ static const struct i2c_adapter cpm_ops = { static int __devinit cpm_i2c_setup(struct cpm_i2c *cpm) { - struct of_device *ofdev = cpm->ofdev; + struct platform_device *ofdev = cpm->ofdev; const u32 *data; int len, ret, i; void __iomem *i2c_base; @@ -634,7 +634,7 @@ static void cpm_i2c_shutdown(struct cpm_i2c *cpm) cpm_muram_free(cpm->i2c_addr); } -static int __devinit cpm_i2c_probe(struct of_device *ofdev, +static int __devinit cpm_i2c_probe(struct platform_device *ofdev, const struct of_device_id *match) { int result, len; @@ -677,6 +677,11 @@ static int __devinit cpm_i2c_probe(struct of_device *ofdev, dev_dbg(&ofdev->dev, "hw routines for %s registered.\n", cpm->adap.name); + /* + * register OF I2C devices + */ + of_i2c_register_devices(&cpm->adap); + return 0; out_shut: cpm_i2c_shutdown(cpm); @@ -687,7 +692,7 @@ out_free: return result; } -static int __devexit cpm_i2c_remove(struct of_device *ofdev) +static int __devexit cpm_i2c_remove(struct platform_device *ofdev) { struct cpm_i2c *cpm = dev_get_drvdata(&ofdev->dev); diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c index 4523364e6722..5795c8398c7c 100644 --- a/drivers/i2c/busses/i2c-davinci.c +++ b/drivers/i2c/busses/i2c-davinci.c @@ -36,14 +36,16 @@ #include <linux/platform_device.h> #include <linux/io.h> #include <linux/slab.h> +#include <linux/cpufreq.h> +#include <linux/gpio.h> #include <mach/hardware.h> - #include <mach/i2c.h> /* ----- global defines ----------------------------------------------- */ #define DAVINCI_I2C_TIMEOUT (1*HZ) +#define DAVINCI_I2C_MAX_TRIES 2 #define I2C_DAVINCI_INTR_ALL (DAVINCI_I2C_IMR_AAS | \ DAVINCI_I2C_IMR_SCD | \ DAVINCI_I2C_IMR_ARDY | \ @@ -72,37 +74,29 @@ #define DAVINCI_I2C_IVR_NACK 0x02 #define DAVINCI_I2C_IVR_AL 0x01 -#define DAVINCI_I2C_STR_BB (1 << 12) -#define DAVINCI_I2C_STR_RSFULL (1 << 11) -#define DAVINCI_I2C_STR_SCD (1 << 5) -#define DAVINCI_I2C_STR_ARDY (1 << 2) -#define DAVINCI_I2C_STR_NACK (1 << 1) -#define DAVINCI_I2C_STR_AL (1 << 0) - -#define DAVINCI_I2C_MDR_NACK (1 << 15) -#define DAVINCI_I2C_MDR_STT (1 << 13) -#define DAVINCI_I2C_MDR_STP (1 << 11) -#define DAVINCI_I2C_MDR_MST (1 << 10) -#define DAVINCI_I2C_MDR_TRX (1 << 9) -#define DAVINCI_I2C_MDR_XA (1 << 8) -#define DAVINCI_I2C_MDR_RM (1 << 7) -#define DAVINCI_I2C_MDR_IRS (1 << 5) - -#define DAVINCI_I2C_IMR_AAS (1 << 6) -#define DAVINCI_I2C_IMR_SCD (1 << 5) -#define DAVINCI_I2C_IMR_XRDY (1 << 4) -#define DAVINCI_I2C_IMR_RRDY (1 << 3) -#define DAVINCI_I2C_IMR_ARDY (1 << 2) -#define DAVINCI_I2C_IMR_NACK (1 << 1) -#define DAVINCI_I2C_IMR_AL (1 << 0) - -#define MOD_REG_BIT(val, mask, set) do { \ - if (set) { \ - val |= mask; \ - } else { \ - val &= ~mask; \ - } \ -} while (0) +#define DAVINCI_I2C_STR_BB BIT(12) +#define DAVINCI_I2C_STR_RSFULL BIT(11) +#define DAVINCI_I2C_STR_SCD BIT(5) +#define DAVINCI_I2C_STR_ARDY BIT(2) +#define DAVINCI_I2C_STR_NACK BIT(1) +#define DAVINCI_I2C_STR_AL BIT(0) + +#define DAVINCI_I2C_MDR_NACK BIT(15) +#define DAVINCI_I2C_MDR_STT BIT(13) +#define DAVINCI_I2C_MDR_STP BIT(11) +#define DAVINCI_I2C_MDR_MST BIT(10) +#define DAVINCI_I2C_MDR_TRX BIT(9) +#define DAVINCI_I2C_MDR_XA BIT(8) +#define DAVINCI_I2C_MDR_RM BIT(7) +#define DAVINCI_I2C_MDR_IRS BIT(5) + +#define DAVINCI_I2C_IMR_AAS BIT(6) +#define DAVINCI_I2C_IMR_SCD BIT(5) +#define DAVINCI_I2C_IMR_XRDY BIT(4) +#define DAVINCI_I2C_IMR_RRDY BIT(3) +#define DAVINCI_I2C_IMR_ARDY BIT(2) +#define DAVINCI_I2C_IMR_NACK BIT(1) +#define DAVINCI_I2C_IMR_AL BIT(0) struct davinci_i2c_dev { struct device *dev; @@ -113,8 +107,13 @@ struct davinci_i2c_dev { u8 *buf; size_t buf_len; int irq; + int stop; u8 terminate; struct i2c_adapter adapter; +#ifdef CONFIG_CPU_FREQ + struct completion xfr_complete; + struct notifier_block freq_transition; +#endif }; /* default platform data to use if not supplied in the platform_device */ @@ -134,12 +133,59 @@ static inline u16 davinci_i2c_read_reg(struct davinci_i2c_dev *i2c_dev, int reg) return __raw_readw(i2c_dev->base + reg); } -/* - * This functions configures I2C and brings I2C out of reset. - * This function is called during I2C init function. This function - * also gets called if I2C encounters any errors. +/* Generate a pulse on the i2c clock pin. */ +static void generic_i2c_clock_pulse(unsigned int scl_pin) +{ + u16 i; + + if (scl_pin) { + /* Send high and low on the SCL line */ + for (i = 0; i < 9; i++) { + gpio_set_value(scl_pin, 0); + udelay(20); + gpio_set_value(scl_pin, 1); + udelay(20); + } + } +} + +/* This routine does i2c bus recovery as specified in the + * i2c protocol Rev. 03 section 3.16 titled "Bus clear" */ -static int i2c_davinci_init(struct davinci_i2c_dev *dev) +static void i2c_recover_bus(struct davinci_i2c_dev *dev) +{ + u32 flag = 0; + struct davinci_i2c_platform_data *pdata = dev->dev->platform_data; + + dev_err(dev->dev, "initiating i2c bus recovery\n"); + /* Send NACK to the slave */ + flag = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); + flag |= DAVINCI_I2C_MDR_NACK; + /* write the data into mode register */ + davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag); + if (pdata) + generic_i2c_clock_pulse(pdata->scl_pin); + /* Send STOP */ + flag = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); + flag |= DAVINCI_I2C_MDR_STP; + davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag); +} + +static inline void davinci_i2c_reset_ctrl(struct davinci_i2c_dev *i2c_dev, + int val) +{ + u16 w; + + w = davinci_i2c_read_reg(i2c_dev, DAVINCI_I2C_MDR_REG); + if (!val) /* put I2C into reset */ + w &= ~DAVINCI_I2C_MDR_IRS; + else /* take I2C out of reset */ + w |= DAVINCI_I2C_MDR_IRS; + + davinci_i2c_write_reg(i2c_dev, DAVINCI_I2C_MDR_REG, w); +} + +static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev) { struct davinci_i2c_platform_data *pdata = dev->dev->platform_data; u16 psc; @@ -148,15 +194,6 @@ static int i2c_davinci_init(struct davinci_i2c_dev *dev) u32 clkh; u32 clkl; u32 input_clock = clk_get_rate(dev->clk); - u16 w; - - if (!pdata) - pdata = &davinci_i2c_platform_data_default; - - /* put I2C into reset */ - w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); - MOD_REG_BIT(w, DAVINCI_I2C_MDR_IRS, 0); - davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w); /* NOTE: I2C Clock divider programming info * As per I2C specs the following formulas provide prescaler @@ -188,12 +225,32 @@ static int i2c_davinci_init(struct davinci_i2c_dev *dev) davinci_i2c_write_reg(dev, DAVINCI_I2C_CLKH_REG, clkh); davinci_i2c_write_reg(dev, DAVINCI_I2C_CLKL_REG, clkl); + dev_dbg(dev->dev, "input_clock = %d, CLK = %d\n", input_clock, clk); +} + +/* + * This function configures I2C and brings I2C out of reset. + * This function is called during I2C init function. This function + * also gets called if I2C encounters any errors. + */ +static int i2c_davinci_init(struct davinci_i2c_dev *dev) +{ + struct davinci_i2c_platform_data *pdata = dev->dev->platform_data; + + if (!pdata) + pdata = &davinci_i2c_platform_data_default; + + /* put I2C into reset */ + davinci_i2c_reset_ctrl(dev, 0); + + /* compute clock dividers */ + i2c_davinci_calc_clk_dividers(dev); + /* Respond at reserved "SMBus Host" slave address" (and zero); * we seem to have no option to not respond... */ davinci_i2c_write_reg(dev, DAVINCI_I2C_OAR_REG, 0x08); - dev_dbg(dev->dev, "input_clock = %d, CLK = %d\n", input_clock, clk); dev_dbg(dev->dev, "PSC = %d\n", davinci_i2c_read_reg(dev, DAVINCI_I2C_PSC_REG)); dev_dbg(dev->dev, "CLKL = %d\n", @@ -204,9 +261,7 @@ static int i2c_davinci_init(struct davinci_i2c_dev *dev) pdata->bus_freq, pdata->bus_delay); /* Take the I2C module out of reset: */ - w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); - MOD_REG_BIT(w, DAVINCI_I2C_MDR_IRS, 1); - davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w); + davinci_i2c_reset_ctrl(dev, 1); /* Enable interrupts */ davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, I2C_DAVINCI_INTR_ALL); @@ -221,14 +276,22 @@ static int i2c_davinci_wait_bus_not_busy(struct davinci_i2c_dev *dev, char allow_sleep) { unsigned long timeout; + static u16 to_cnt; timeout = jiffies + dev->adapter.timeout; while (davinci_i2c_read_reg(dev, DAVINCI_I2C_STR_REG) & DAVINCI_I2C_STR_BB) { - if (time_after(jiffies, timeout)) { - dev_warn(dev->dev, - "timeout waiting for bus ready\n"); - return -ETIMEDOUT; + if (to_cnt <= DAVINCI_I2C_MAX_TRIES) { + if (time_after(jiffies, timeout)) { + dev_warn(dev->dev, + "timeout waiting for bus ready\n"); + to_cnt++; + return -ETIMEDOUT; + } else { + to_cnt = 0; + i2c_recover_bus(dev); + i2c_davinci_init(dev); + } } if (allow_sleep) schedule_timeout(1); @@ -250,9 +313,6 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop) u16 w; int r; - if (msg->len == 0) - return -EINVAL; - if (!pdata) pdata = &davinci_i2c_platform_data_default; /* Introduce a delay, required for some boards (e.g Davinci EVM) */ @@ -264,40 +324,64 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop) dev->buf = msg->buf; dev->buf_len = msg->len; + dev->stop = stop; davinci_i2c_write_reg(dev, DAVINCI_I2C_CNT_REG, dev->buf_len); INIT_COMPLETION(dev->cmd_complete); dev->cmd_err = 0; - /* Take I2C out of reset, configure it as master and set the - * start bit */ - flag = DAVINCI_I2C_MDR_IRS | DAVINCI_I2C_MDR_MST | DAVINCI_I2C_MDR_STT; + /* Take I2C out of reset and configure it as master */ + flag = DAVINCI_I2C_MDR_IRS | DAVINCI_I2C_MDR_MST; /* if the slave address is ten bit address, enable XA bit */ if (msg->flags & I2C_M_TEN) flag |= DAVINCI_I2C_MDR_XA; if (!(msg->flags & I2C_M_RD)) flag |= DAVINCI_I2C_MDR_TRX; - if (stop) - flag |= DAVINCI_I2C_MDR_STP; + if (msg->len == 0) + flag |= DAVINCI_I2C_MDR_RM; /* Enable receive or transmit interrupts */ w = davinci_i2c_read_reg(dev, DAVINCI_I2C_IMR_REG); if (msg->flags & I2C_M_RD) - MOD_REG_BIT(w, DAVINCI_I2C_IMR_RRDY, 1); + w |= DAVINCI_I2C_IMR_RRDY; else - MOD_REG_BIT(w, DAVINCI_I2C_IMR_XRDY, 1); + w |= DAVINCI_I2C_IMR_XRDY; davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, w); dev->terminate = 0; - /* write the data into mode register */ + + /* + * Write mode register first as needed for correct behaviour + * on OMAP-L138, but don't set STT yet to avoid a race with XRDY + * occuring before we have loaded DXR + */ + davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag); + + /* + * First byte should be set here, not after interrupt, + * because transmit-data-ready interrupt can come before + * NACK-interrupt during sending of previous message and + * ICDXR may have wrong data + * It also saves us one interrupt, slightly faster + */ + if ((!(msg->flags & I2C_M_RD)) && dev->buf_len) { + davinci_i2c_write_reg(dev, DAVINCI_I2C_DXR_REG, *dev->buf++); + dev->buf_len--; + } + + /* Set STT to begin transmit now DXR is loaded */ + flag |= DAVINCI_I2C_MDR_STT; + if (stop && msg->len != 0) + flag |= DAVINCI_I2C_MDR_STP; davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag); r = wait_for_completion_interruptible_timeout(&dev->cmd_complete, dev->adapter.timeout); if (r == 0) { dev_err(dev->dev, "controller timed out\n"); + i2c_recover_bus(dev); i2c_davinci_init(dev); dev->buf_len = 0; return -ETIMEDOUT; @@ -334,7 +418,7 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop) return msg->len; if (stop) { w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); - MOD_REG_BIT(w, DAVINCI_I2C_MDR_STP, 1); + w |= DAVINCI_I2C_MDR_STP; davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w); } return -EREMOTEIO; @@ -367,12 +451,17 @@ i2c_davinci_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) if (ret < 0) return ret; } + +#ifdef CONFIG_CPU_FREQ + complete(&dev->xfr_complete); +#endif + return num; } static u32 i2c_davinci_func(struct i2c_adapter *adap) { - return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; } static void terminate_read(struct davinci_i2c_dev *dev) @@ -431,6 +520,14 @@ static irqreturn_t i2c_davinci_isr(int this_irq, void *dev_id) case DAVINCI_I2C_IVR_ARDY: davinci_i2c_write_reg(dev, DAVINCI_I2C_STR_REG, DAVINCI_I2C_STR_ARDY); + if (((dev->buf_len == 0) && (dev->stop != 0)) || + (dev->cmd_err & DAVINCI_I2C_STR_NACK)) { + w = davinci_i2c_read_reg(dev, + DAVINCI_I2C_MDR_REG); + w |= DAVINCI_I2C_MDR_STP; + davinci_i2c_write_reg(dev, + DAVINCI_I2C_MDR_REG, w); + } complete(&dev->cmd_complete); break; @@ -462,7 +559,7 @@ static irqreturn_t i2c_davinci_isr(int this_irq, void *dev_id) w = davinci_i2c_read_reg(dev, DAVINCI_I2C_IMR_REG); - MOD_REG_BIT(w, DAVINCI_I2C_IMR_XRDY, 0); + w &= ~DAVINCI_I2C_IMR_XRDY; davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, w); @@ -491,6 +588,48 @@ static irqreturn_t i2c_davinci_isr(int this_irq, void *dev_id) return count ? IRQ_HANDLED : IRQ_NONE; } +#ifdef CONFIG_CPU_FREQ +static int i2c_davinci_cpufreq_transition(struct notifier_block *nb, + unsigned long val, void *data) +{ + struct davinci_i2c_dev *dev; + + dev = container_of(nb, struct davinci_i2c_dev, freq_transition); + if (val == CPUFREQ_PRECHANGE) { + wait_for_completion(&dev->xfr_complete); + davinci_i2c_reset_ctrl(dev, 0); + } else if (val == CPUFREQ_POSTCHANGE) { + i2c_davinci_calc_clk_dividers(dev); + davinci_i2c_reset_ctrl(dev, 1); + } + + return 0; +} + +static inline int i2c_davinci_cpufreq_register(struct davinci_i2c_dev *dev) +{ + dev->freq_transition.notifier_call = i2c_davinci_cpufreq_transition; + + return cpufreq_register_notifier(&dev->freq_transition, + CPUFREQ_TRANSITION_NOTIFIER); +} + +static inline void i2c_davinci_cpufreq_deregister(struct davinci_i2c_dev *dev) +{ + cpufreq_unregister_notifier(&dev->freq_transition, + CPUFREQ_TRANSITION_NOTIFIER); +} +#else +static inline int i2c_davinci_cpufreq_register(struct davinci_i2c_dev *dev) +{ + return 0; +} + +static inline void i2c_davinci_cpufreq_deregister(struct davinci_i2c_dev *dev) +{ +} +#endif + static struct i2c_algorithm i2c_davinci_algo = { .master_xfer = i2c_davinci_xfer, .functionality = i2c_davinci_func, @@ -530,6 +669,9 @@ static int davinci_i2c_probe(struct platform_device *pdev) } init_completion(&dev->cmd_complete); +#ifdef CONFIG_CPU_FREQ + init_completion(&dev->xfr_complete); +#endif dev->dev = get_device(&pdev->dev); dev->irq = irq->start; platform_set_drvdata(pdev, dev); @@ -541,7 +683,12 @@ static int davinci_i2c_probe(struct platform_device *pdev) } clk_enable(dev->clk); - dev->base = (void __iomem *)IO_ADDRESS(mem->start); + dev->base = ioremap(mem->start, resource_size(mem)); + if (!dev->base) { + r = -EBUSY; + goto err_mem_ioremap; + } + i2c_davinci_init(dev); r = request_irq(dev->irq, i2c_davinci_isr, 0, pdev->name, dev); @@ -550,6 +697,12 @@ static int davinci_i2c_probe(struct platform_device *pdev) goto err_unuse_clocks; } + r = i2c_davinci_cpufreq_register(dev); + if (r) { + dev_err(&pdev->dev, "failed to register cpufreq\n"); + goto err_free_irq; + } + adap = &dev->adapter; i2c_set_adapdata(adap, dev); adap->owner = THIS_MODULE; @@ -571,6 +724,8 @@ static int davinci_i2c_probe(struct platform_device *pdev) err_free_irq: free_irq(dev->irq, dev); err_unuse_clocks: + iounmap(dev->base); +err_mem_ioremap: clk_disable(dev->clk); clk_put(dev->clk); dev->clk = NULL; @@ -589,6 +744,8 @@ static int davinci_i2c_remove(struct platform_device *pdev) struct davinci_i2c_dev *dev = platform_get_drvdata(pdev); struct resource *mem; + i2c_davinci_cpufreq_deregister(dev); + platform_set_drvdata(pdev, NULL); i2c_del_adapter(&dev->adapter); put_device(&pdev->dev); @@ -599,6 +756,7 @@ static int davinci_i2c_remove(struct platform_device *pdev) davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, 0); free_irq(IRQ_I2C, dev); + iounmap(dev->base); kfree(dev); mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); @@ -606,6 +764,41 @@ static int davinci_i2c_remove(struct platform_device *pdev) return 0; } +#ifdef CONFIG_PM +static int davinci_i2c_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct davinci_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + + /* put I2C into reset */ + davinci_i2c_reset_ctrl(i2c_dev, 0); + clk_disable(i2c_dev->clk); + + return 0; +} + +static int davinci_i2c_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct davinci_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + + clk_enable(i2c_dev->clk); + /* take I2C out of reset */ + davinci_i2c_reset_ctrl(i2c_dev, 1); + + return 0; +} + +static const struct dev_pm_ops davinci_i2c_pm = { + .suspend = davinci_i2c_suspend, + .resume = davinci_i2c_resume, +}; + +#define davinci_i2c_pm_ops (&davinci_i2c_pm) +#else +#define davinci_i2c_pm_ops NULL +#endif + /* work with hotplug and coldplug */ MODULE_ALIAS("platform:i2c_davinci"); @@ -615,6 +808,7 @@ static struct platform_driver davinci_i2c_driver = { .driver = { .name = "i2c_davinci", .owner = THIS_MODULE, + .pm = davinci_i2c_pm_ops, }, }; diff --git a/drivers/i2c/busses/i2c-ibm_iic.c b/drivers/i2c/busses/i2c-ibm_iic.c index 1168d61418c9..6e3c38240336 100644 --- a/drivers/i2c/busses/i2c-ibm_iic.c +++ b/drivers/i2c/busses/i2c-ibm_iic.c @@ -41,7 +41,6 @@ #include <asm/irq.h> #include <linux/io.h> #include <linux/i2c.h> -#include <linux/i2c-id.h> #include <linux/of_platform.h> #include <linux/of_i2c.h> @@ -661,7 +660,7 @@ static inline u8 iic_clckdiv(unsigned int opb) return (u8)((opb + 9) / 10 - 1); } -static int __devinit iic_request_irq(struct of_device *ofdev, +static int __devinit iic_request_irq(struct platform_device *ofdev, struct ibm_iic_private *dev) { struct device_node *np = ofdev->dev.of_node; @@ -692,7 +691,7 @@ static int __devinit iic_request_irq(struct of_device *ofdev, /* * Register single IIC interface */ -static int __devinit iic_probe(struct of_device *ofdev, +static int __devinit iic_probe(struct platform_device *ofdev, const struct of_device_id *match) { struct device_node *np = ofdev->dev.of_node; @@ -761,6 +760,9 @@ static int __devinit iic_probe(struct of_device *ofdev, dev_info(&ofdev->dev, "using %s mode\n", dev->fast_mode ? "fast (400 kHz)" : "standard (100 kHz)"); + /* Now register all the child nodes */ + of_i2c_register_devices(adap); + return 0; error_cleanup: @@ -780,7 +782,7 @@ error_cleanup: /* * Cleanup initialized IIC interface */ -static int __devexit iic_remove(struct of_device *ofdev) +static int __devexit iic_remove(struct platform_device *ofdev) { struct ibm_iic_private *dev = dev_get_drvdata(&ofdev->dev); diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index d1ff9408dc1f..4c2a62b75b5c 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -159,15 +159,9 @@ static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy) static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx) { - int result; - - result = wait_event_interruptible_timeout(i2c_imx->queue, - i2c_imx->i2csr & I2SR_IIF, HZ / 10); + wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10); - if (unlikely(result < 0)) { - dev_dbg(&i2c_imx->adapter.dev, "<%s> result < 0\n", __func__); - return result; - } else if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) { + if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) { dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__); return -ETIMEDOUT; } @@ -295,7 +289,7 @@ static irqreturn_t i2c_imx_isr(int irq, void *dev_id) i2c_imx->i2csr = temp; temp &= ~I2SR_IIF; writeb(temp, i2c_imx->base + IMX_I2C_I2SR); - wake_up_interruptible(&i2c_imx->queue); + wake_up(&i2c_imx->queue); return IRQ_HANDLED; } diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c index 6545d1c99b61..b74e6dc6886c 100644 --- a/drivers/i2c/busses/i2c-mpc.c +++ b/drivers/i2c/busses/i2c-mpc.c @@ -560,7 +560,7 @@ static struct i2c_adapter mpc_ops = { .timeout = HZ, }; -static int __devinit fsl_i2c_probe(struct of_device *op, +static int __devinit fsl_i2c_probe(struct platform_device *op, const struct of_device_id *match) { struct mpc_i2c *i2c; @@ -632,6 +632,7 @@ static int __devinit fsl_i2c_probe(struct of_device *op, dev_err(i2c->dev, "failed to add adapter\n"); goto fail_add; } + of_i2c_register_devices(&i2c->adap); return result; @@ -646,7 +647,7 @@ static int __devinit fsl_i2c_probe(struct of_device *op, return result; }; -static int __devexit fsl_i2c_remove(struct of_device *op) +static int __devexit fsl_i2c_remove(struct platform_device *op) { struct mpc_i2c *i2c = dev_get_drvdata(&op->dev); diff --git a/drivers/i2c/busses/i2c-nuc900.c b/drivers/i2c/busses/i2c-nuc900.c new file mode 100644 index 000000000000..72434263787b --- /dev/null +++ b/drivers/i2c/busses/i2c-nuc900.c @@ -0,0 +1,708 @@ +/* + * linux/drivers/i2c/busses/i2c-nuc900.c + * + * Copyright (c) 2010 Nuvoton technology corporation. + * + * This driver based on S3C2410 I2C driver of Ben Dooks <ben-Y5A6D6n0/KfQXOPxS62xeg@public.gmane.org>. + * Written by Wan ZongShun <mcuos.com-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation;version 2 of the License. + * + */ + +#include <linux/kernel.h> +#include <linux/module.h> + +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/time.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/clk.h> +#include <linux/cpufreq.h> +#include <linux/slab.h> +#include <linux/io.h> + +#include <mach/mfp.h> +#include <mach/i2c.h> + +/* nuc900 i2c registers offset */ + +#define CSR 0x00 +#define DIVIDER 0x04 +#define CMDR 0x08 +#define SWR 0x0C +#define RXR 0x10 +#define TXR 0x14 + +/* nuc900 i2c CSR register bits */ + +#define IRQEN 0x003 +#define I2CBUSY 0x400 +#define I2CSTART 0x018 +#define IRQFLAG 0x004 +#define ARBIT_LOST 0x200 +#define SLAVE_ACK 0x800 + +/* nuc900 i2c CMDR register bits */ + +#define I2C_CMD_START 0x10 +#define I2C_CMD_STOP 0x08 +#define I2C_CMD_READ 0x04 +#define I2C_CMD_WRITE 0x02 +#define I2C_CMD_NACK 0x01 + +/* i2c controller state */ + +enum nuc900_i2c_state { + STATE_IDLE, + STATE_START, + STATE_READ, + STATE_WRITE, + STATE_STOP +}; + +/* i2c controller private data */ + +struct nuc900_i2c { + spinlock_t lock; + wait_queue_head_t wait; + + struct i2c_msg *msg; + unsigned int msg_num; + unsigned int msg_idx; + unsigned int msg_ptr; + unsigned int irq; + + enum nuc900_i2c_state state; + + void __iomem *regs; + struct clk *clk; + struct device *dev; + struct resource *ioarea; + struct i2c_adapter adap; +}; + +/* nuc900_i2c_master_complete + * + * complete the message and wake up the caller, using the given return code, + * or zero to mean ok. +*/ + +static inline void nuc900_i2c_master_complete(struct nuc900_i2c *i2c, int ret) +{ + dev_dbg(i2c->dev, "master_complete %d\n", ret); + + i2c->msg_ptr = 0; + i2c->msg = NULL; + i2c->msg_idx++; + i2c->msg_num = 0; + if (ret) + i2c->msg_idx = ret; + + wake_up(&i2c->wait); +} + +/* irq enable/disable functions */ + +static inline void nuc900_i2c_disable_irq(struct nuc900_i2c *i2c) +{ + unsigned long tmp; + + tmp = readl(i2c->regs + CSR); + writel(tmp & ~IRQEN, i2c->regs + CSR); +} + +static inline void nuc900_i2c_enable_irq(struct nuc900_i2c *i2c) +{ + unsigned long tmp; + + tmp = readl(i2c->regs + CSR); + writel(tmp | IRQEN, i2c->regs + CSR); +} + + +/* nuc900_i2c_message_start + * + * put the start of a message onto the bus +*/ + +static void nuc900_i2c_message_start(struct nuc900_i2c *i2c, + struct i2c_msg *msg) +{ + unsigned int addr = (msg->addr & 0x7f) << 1; + + if (msg->flags & I2C_M_RD) + addr |= 0x1; + writel(addr & 0xff, i2c->regs + TXR); + writel(I2C_CMD_START | I2C_CMD_WRITE, i2c->regs + CMDR); +} + +static inline void nuc900_i2c_stop(struct nuc900_i2c *i2c, int ret) +{ + + dev_dbg(i2c->dev, "STOP\n"); + + /* stop the transfer */ + i2c->state = STATE_STOP; + writel(I2C_CMD_STOP, i2c->regs + CMDR); + + nuc900_i2c_master_complete(i2c, ret); + nuc900_i2c_disable_irq(i2c); +} + +/* helper functions to determine the current state in the set of + * messages we are sending +*/ + +/* is_lastmsg() + * + * returns TRUE if the current message is the last in the set +*/ + +static inline int is_lastmsg(struct nuc900_i2c *i2c) +{ + return i2c->msg_idx >= (i2c->msg_num - 1); +} + +/* is_msglast + * + * returns TRUE if we this is the last byte in the current message +*/ + +static inline int is_msglast(struct nuc900_i2c *i2c) +{ + return i2c->msg_ptr == i2c->msg->len-1; +} + +/* is_msgend + * + * returns TRUE if we reached the end of the current message +*/ + +static inline int is_msgend(struct nuc900_i2c *i2c) +{ + return i2c->msg_ptr >= i2c->msg->len; +} + +/* i2c_nuc900_irq_nextbyte + * + * process an interrupt and work out what to do + */ + +static void i2c_nuc900_irq_nextbyte(struct nuc900_i2c *i2c, + unsigned long iicstat) +{ + unsigned char byte; + + switch (i2c->state) { + + case STATE_IDLE: + dev_err(i2c->dev, "%s: called in STATE_IDLE\n", __func__); + break; + + case STATE_STOP: + dev_err(i2c->dev, "%s: called in STATE_STOP\n", __func__); + nuc900_i2c_disable_irq(i2c); + break; + + case STATE_START: + /* last thing we did was send a start condition on the + * bus, or started a new i2c message + */ + + if (iicstat & SLAVE_ACK && + !(i2c->msg->flags & I2C_M_IGNORE_NAK)) { + /* ack was not received... */ + + dev_dbg(i2c->dev, "ack was not received\n"); + nuc900_i2c_stop(i2c, -ENXIO); + break; + } + + if (i2c->msg->flags & I2C_M_RD) + i2c->state = STATE_READ; + else + i2c->state = STATE_WRITE; + + /* terminate the transfer if there is nothing to do + * as this is used by the i2c probe to find devices. + */ + + if (is_lastmsg(i2c) && i2c->msg->len == 0) { + nuc900_i2c_stop(i2c, 0); + break; + } + + if (i2c->state == STATE_READ) + goto prepare_read; + + /* fall through to the write state, as we will need to + * send a byte as well + */ + + case STATE_WRITE: + /* we are writing data to the device... check for the + * end of the message, and if so, work out what to do + */ + + if (!(i2c->msg->flags & I2C_M_IGNORE_NAK)) { + if (iicstat & SLAVE_ACK) { + dev_dbg(i2c->dev, "WRITE: No Ack\n"); + + nuc900_i2c_stop(i2c, -ECONNREFUSED); + break; + } + } + +retry_write: + + if (!is_msgend(i2c)) { + byte = i2c->msg->buf[i2c->msg_ptr++]; + writeb(byte, i2c->regs + TXR); + writel(I2C_CMD_WRITE, i2c->regs + CMDR); + + } else if (!is_lastmsg(i2c)) { + /* we need to go to the next i2c message */ + + dev_dbg(i2c->dev, "WRITE: Next Message\n"); + + i2c->msg_ptr = 0; + i2c->msg_idx++; + i2c->msg++; + + /* check to see if we need to do another message */ + if (i2c->msg->flags & I2C_M_NOSTART) { + + if (i2c->msg->flags & I2C_M_RD) { + /* cannot do this, the controller + * forces us to send a new START + * when we change direction + */ + + nuc900_i2c_stop(i2c, -EINVAL); + } + + goto retry_write; + } else { + /* send the new start */ + nuc900_i2c_message_start(i2c, i2c->msg); + i2c->state = STATE_START; + } + + } else { + /* send stop */ + + nuc900_i2c_stop(i2c, 0); + } + break; + + case STATE_READ: + /* we have a byte of data in the data register, do + * something with it, and then work out wether we are + * going to do any more read/write + */ + + byte = readb(i2c->regs + RXR); + i2c->msg->buf[i2c->msg_ptr++] = byte; + +prepare_read: + if (is_msglast(i2c)) { + /* last byte of buffer */ + + if (is_lastmsg(i2c)) + writel(I2C_CMD_READ | I2C_CMD_NACK, + i2c->regs + CMDR); + + } else if (is_msgend(i2c)) { + /* ok, we've read the entire buffer, see if there + * is anything else we need to do + */ + + if (is_lastmsg(i2c)) { + /* last message, send stop and complete */ + dev_dbg(i2c->dev, "READ: Send Stop\n"); + + nuc900_i2c_stop(i2c, 0); + } else { + /* go to the next transfer */ + dev_dbg(i2c->dev, "READ: Next Transfer\n"); + + i2c->msg_ptr = 0; + i2c->msg_idx++; + i2c->msg++; + + writel(I2C_CMD_READ, i2c->regs + CMDR); + } + + } else { + writel(I2C_CMD_READ, i2c->regs + CMDR); + } + + break; + } +} + +/* nuc900_i2c_irq + * + * top level IRQ servicing routine +*/ + +static irqreturn_t nuc900_i2c_irq(int irqno, void *dev_id) +{ + struct nuc900_i2c *i2c = dev_id; + unsigned long status; + + status = readl(i2c->regs + CSR); + writel(status | IRQFLAG, i2c->regs + CSR); + + if (status & ARBIT_LOST) { + /* deal with arbitration loss */ + dev_err(i2c->dev, "deal with arbitration loss\n"); + goto out; + } + + if (i2c->state == STATE_IDLE) { + dev_dbg(i2c->dev, "IRQ: error i2c->state == IDLE\n"); + goto out; + } + + /* pretty much this leaves us with the fact that we've + * transmitted or received whatever byte we last sent + */ + + i2c_nuc900_irq_nextbyte(i2c, status); + + out: + return IRQ_HANDLED; +} + + +/* nuc900_i2c_set_master + * + * get the i2c bus for a master transaction +*/ + +static int nuc900_i2c_set_master(struct nuc900_i2c *i2c) +{ + int timeout = 400; + + while (timeout-- > 0) { + if (((readl(i2c->regs + SWR) & I2CSTART) == I2CSTART) && + ((readl(i2c->regs + CSR) & I2CBUSY) == 0)) { + return 0; + } + + msleep(1); + } + + return -ETIMEDOUT; +} + +/* nuc900_i2c_doxfer + * + * this starts an i2c transfer +*/ + +static int nuc900_i2c_doxfer(struct nuc900_i2c *i2c, + struct i2c_msg *msgs, int num) +{ + unsigned long iicstat, timeout; + int spins = 20; + int ret; + + ret = nuc900_i2c_set_master(i2c); + if (ret != 0) { + dev_err(i2c->dev, "cannot get bus (error %d)\n", ret); + ret = -EAGAIN; + goto out; + } + + spin_lock_irq(&i2c->lock); + + i2c->msg = msgs; + i2c->msg_num = num; + i2c->msg_ptr = 0; + i2c->msg_idx = 0; + i2c->state = STATE_START; + + nuc900_i2c_message_start(i2c, msgs); + spin_unlock_irq(&i2c->lock); + + timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5); + + ret = i2c->msg_idx; + + /* having these next two as dev_err() makes life very + * noisy when doing an i2cdetect + */ + + if (timeout == 0) + dev_dbg(i2c->dev, "timeout\n"); + else if (ret != num) + dev_dbg(i2c->dev, "incomplete xfer (%d)\n", ret); + + /* ensure the stop has been through the bus */ + + dev_dbg(i2c->dev, "waiting for bus idle\n"); + + /* first, try busy waiting briefly */ + do { + iicstat = readl(i2c->regs + CSR); + } while ((iicstat & I2CBUSY) && --spins); + + /* if that timed out sleep */ + if (!spins) { + msleep(1); + iicstat = readl(i2c->regs + CSR); + } + + if (iicstat & I2CBUSY) + dev_warn(i2c->dev, "timeout waiting for bus idle\n"); + + out: + return ret; +} + +/* nuc900_i2c_xfer + * + * first port of call from the i2c bus code when an message needs + * transferring across the i2c bus. +*/ + +static int nuc900_i2c_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + struct nuc900_i2c *i2c = (struct nuc900_i2c *)adap->algo_data; + int retry; + int ret; + + nuc900_i2c_enable_irq(i2c); + + for (retry = 0; retry < adap->retries; retry++) { + + ret = nuc900_i2c_doxfer(i2c, msgs, num); + + if (ret != -EAGAIN) + return ret; + + dev_dbg(i2c->dev, "Retrying transmission (%d)\n", retry); + + udelay(100); + } + + return -EREMOTEIO; +} + +/* declare our i2c functionality */ +static u32 nuc900_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_PROTOCOL_MANGLING; +} + +/* i2c bus registration info */ + +static const struct i2c_algorithm nuc900_i2c_algorithm = { + .master_xfer = nuc900_i2c_xfer, + .functionality = nuc900_i2c_func, +}; + +/* nuc900_i2c_probe + * + * called by the bus driver when a suitable device is found +*/ + +static int __devinit nuc900_i2c_probe(struct platform_device *pdev) +{ + struct nuc900_i2c *i2c; + struct nuc900_platform_i2c *pdata; + struct resource *res; + int ret; + + pdata = pdev->dev.platform_data; + if (!pdata) { + dev_err(&pdev->dev, "no platform data\n"); + return -EINVAL; + } + + i2c = kzalloc(sizeof(struct nuc900_i2c), GFP_KERNEL); + if (!i2c) { + dev_err(&pdev->dev, "no memory for state\n"); + return -ENOMEM; + } + + strlcpy(i2c->adap.name, "nuc900-i2c0", sizeof(i2c->adap.name)); + i2c->adap.owner = THIS_MODULE; + i2c->adap.algo = &nuc900_i2c_algorithm; + i2c->adap.retries = 2; + i2c->adap.class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + + spin_lock_init(&i2c->lock); + init_waitqueue_head(&i2c->wait); + + /* find the clock and enable it */ + + i2c->dev = &pdev->dev; + i2c->clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(i2c->clk)) { + dev_err(&pdev->dev, "cannot get clock\n"); + ret = -ENOENT; + goto err_noclk; + } + + dev_dbg(&pdev->dev, "clock source %p\n", i2c->clk); + + clk_enable(i2c->clk); + + /* map the registers */ + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (res == NULL) { + dev_err(&pdev->dev, "cannot find IO resource\n"); + ret = -ENOENT; + goto err_clk; + } + + i2c->ioarea = request_mem_region(res->start, resource_size(res), + pdev->name); + + if (i2c->ioarea == NULL) { + dev_err(&pdev->dev, "cannot request IO\n"); + ret = -ENXIO; + goto err_clk; + } + + i2c->regs = ioremap(res->start, resource_size(res)); + + if (i2c->regs == NULL) { + dev_err(&pdev->dev, "cannot map IO\n"); + ret = -ENXIO; + goto err_ioarea; + } + + dev_dbg(&pdev->dev, "registers %p (%p, %p)\n", + i2c->regs, i2c->ioarea, res); + + /* setup info block for the i2c core */ + + i2c->adap.algo_data = i2c; + i2c->adap.dev.parent = &pdev->dev; + + mfp_set_groupg(&pdev->dev); + + clk_get_rate(i2c->clk); + + ret = (i2c->clk.apbfreq)/(pdata->bus_freq * 5) - 1; + writel(ret & 0xffff, i2c->regs + DIVIDER); + + /* find the IRQ for this unit (note, this relies on the init call to + * ensure no current IRQs pending + */ + + i2c->irq = ret = platform_get_irq(pdev, 0); + if (ret <= 0) { + dev_err(&pdev->dev, "cannot find IRQ\n"); + goto err_iomap; + } + + ret = request_irq(i2c->irq, nuc900_i2c_irq, IRQF_DISABLED | IRQF_SHARED, + dev_name(&pdev->dev), i2c); + + if (ret != 0) { + dev_err(&pdev->dev, "cannot claim IRQ %d\n", i2c->irq); + goto err_iomap; + } + + /* Note, previous versions of the driver used i2c_add_adapter() + * to add the bus at any number. We now pass the bus number via + * the platform data, so if unset it will now default to always + * being bus 0. + */ + + i2c->adap.nr = pdata->bus_num; + + ret = i2c_add_numbered_adapter(&i2c->adap); + if (ret < 0) { + dev_err(&pdev->dev, "failed to add bus to i2c core\n"); + goto err_irq; + } + + platform_set_drvdata(pdev, i2c); + + dev_info(&pdev->dev, "%s: NUC900 I2C adapter\n", + dev_name(&i2c->adap.dev)); + return 0; + + err_irq: + free_irq(i2c->irq, i2c); + + err_iomap: + iounmap(i2c->regs); + + err_ioarea: + release_resource(i2c->ioarea); + kfree(i2c->ioarea); + + err_clk: + clk_disable(i2c->clk); + clk_put(i2c->clk); + + err_noclk: + kfree(i2c); + return ret; +} + +/* nuc900_i2c_remove + * + * called when device is removed from the bus +*/ + +static int __devexit nuc900_i2c_remove(struct platform_device *pdev) +{ + struct nuc900_i2c *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adap); + free_irq(i2c->irq, i2c); + + clk_disable(i2c->clk); + clk_put(i2c->clk); + + iounmap(i2c->regs); + + release_resource(i2c->ioarea); + kfree(i2c->ioarea); + kfree(i2c); + + return 0; +} + +static struct platform_driver nuc900_i2c_driver = { + .probe = nuc900_i2c_probe, + .remove = __devexit_p(nuc900_i2c_remove), + .driver = { + .owner = THIS_MODULE, + .name = "nuc900-i2c0", + }, +}; + +static int __init i2c_adap_nuc900_init(void) +{ + return platform_driver_register(&nuc900_i2c_driver); +} + +static void __exit i2c_adap_nuc900_exit(void) +{ + platform_driver_unregister(&nuc900_i2c_driver); +} +subsys_initcall(i2c_adap_nuc900_init); +module_exit(i2c_adap_nuc900_exit); + +MODULE_DESCRIPTION("NUC900 I2C Bus driver"); +MODULE_AUTHOR("Wan ZongShun, <mcuos.com-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:nuc900-i2c0"); diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c index 0e9f85d0a835..56dbe54e8811 100644 --- a/drivers/i2c/busses/i2c-octeon.c +++ b/drivers/i2c/busses/i2c-octeon.c @@ -218,7 +218,7 @@ static int octeon_i2c_wait(struct octeon_i2c *i2c) return result; } else if (result == 0) { dev_dbg(i2c->dev, "%s: timeout\n", __func__); - result = -ETIMEDOUT; + return -ETIMEDOUT; } return 0; diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index 7674efb55378..b33c78586bfc 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -680,6 +680,8 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) if (r == 0) r = num; + + omap_i2c_wait_for_bb(dev); out: omap_i2c_idle(dev); return r; diff --git a/drivers/i2c/busses/i2c-pasemi.c b/drivers/i2c/busses/i2c-pasemi.c index 4174101660c9..837b8c1aa02a 100644 --- a/drivers/i2c/busses/i2c-pasemi.c +++ b/drivers/i2c/busses/i2c-pasemi.c @@ -88,7 +88,7 @@ static void pasemi_smb_clear(struct pasemi_smbus *smbus) reg_write(smbus, REG_SMSTA, status); } -static unsigned int pasemi_smb_waitready(struct pasemi_smbus *smbus) +static int pasemi_smb_waitready(struct pasemi_smbus *smbus) { int timeout = 10; unsigned int status; diff --git a/drivers/i2c/busses/i2c-pca-isa.c b/drivers/i2c/busses/i2c-pca-isa.c index bbd77603a417..29933f87d8fa 100644 --- a/drivers/i2c/busses/i2c-pca-isa.c +++ b/drivers/i2c/busses/i2c-pca-isa.c @@ -71,8 +71,8 @@ static int pca_isa_readbyte(void *pd, int reg) static int pca_isa_waitforcompletion(void *pd) { - long ret = ~0; unsigned long timeout; + long ret; if (irq > -1) { ret = wait_event_timeout(pca_wait, @@ -81,11 +81,15 @@ static int pca_isa_waitforcompletion(void *pd) } else { /* Do polling */ timeout = jiffies + pca_isa_ops.timeout; - while (((pca_isa_readbyte(pd, I2C_PCA_CON) - & I2C_PCA_CON_SI) == 0) - && (ret = time_before(jiffies, timeout))) + do { + ret = time_before(jiffies, timeout); + if (pca_isa_readbyte(pd, I2C_PCA_CON) + & I2C_PCA_CON_SI) + break; udelay(100); + } while (ret); } + return ret > 0; } diff --git a/drivers/i2c/busses/i2c-pca-platform.c b/drivers/i2c/busses/i2c-pca-platform.c index ef5c78487eb7..ace67995d7de 100644 --- a/drivers/i2c/busses/i2c-pca-platform.c +++ b/drivers/i2c/busses/i2c-pca-platform.c @@ -80,8 +80,8 @@ static void i2c_pca_pf_writebyte32(void *pd, int reg, int val) static int i2c_pca_pf_waitforcompletion(void *pd) { struct i2c_pca_pf_data *i2c = pd; - long ret = ~0; unsigned long timeout; + long ret; if (i2c->irq) { ret = wait_event_timeout(i2c->wait, @@ -90,10 +90,13 @@ static int i2c_pca_pf_waitforcompletion(void *pd) } else { /* Do polling */ timeout = jiffies + i2c->adap.timeout; - while (((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) - & I2C_PCA_CON_SI) == 0) - && (ret = time_before(jiffies, timeout))) + do { + ret = time_before(jiffies, timeout); + if (i2c->algo_data.read_byte(i2c, I2C_PCA_CON) + & I2C_PCA_CON_SI) + break; udelay(100); + } while (ret); } return ret > 0; @@ -221,7 +224,7 @@ static int __devinit i2c_pca_pf_probe(struct platform_device *pdev) if (irq) { ret = request_irq(irq, i2c_pca_pf_handler, - IRQF_TRIGGER_FALLING, i2c->adap.name, i2c); + IRQF_TRIGGER_FALLING, pdev->name, i2c); if (ret) goto e_reqirq; } diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c index 020ff23d762f..f4c19a97e0b3 100644 --- a/drivers/i2c/busses/i2c-pxa.c +++ b/drivers/i2c/busses/i2c-pxa.c @@ -22,7 +22,6 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/i2c.h> -#include <linux/i2c-id.h> #include <linux/init.h> #include <linux/time.h> #include <linux/sched.h> @@ -1001,7 +1000,7 @@ static int i2c_pxa_probe(struct platform_device *dev) struct pxa_i2c *i2c; struct resource *res; struct i2c_pxa_platform_data *plat = dev->dev.platform_data; - struct platform_device_id *id = platform_get_device_id(dev); + const struct platform_device_id *id = platform_get_device_id(dev); int ret; int irq; diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c index 72902e0bbfa7..6a292ea5e35c 100644 --- a/drivers/i2c/busses/i2c-s3c2410.c +++ b/drivers/i2c/busses/i2c-s3c2410.c @@ -24,7 +24,6 @@ #include <linux/module.h> #include <linux/i2c.h> -#include <linux/i2c-id.h> #include <linux/init.h> #include <linux/time.h> #include <linux/interrupt.h> @@ -662,8 +661,8 @@ static int s3c24xx_i2c_clockrate(struct s3c24xx_i2c *i2c, unsigned int *got) unsigned long sda_delay; if (pdata->sda_delay) { - sda_delay = (freq / 1000) * pdata->sda_delay; - sda_delay /= 1000000; + sda_delay = clkin * pdata->sda_delay; + sda_delay = DIV_ROUND_UP(sda_delay, 1000000); sda_delay = DIV_ROUND_UP(sda_delay, 5); if (sda_delay > 3) sda_delay = 3; diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c index ffb405d7c6f2..598c49acaeb5 100644 --- a/drivers/i2c/busses/i2c-sh_mobile.c +++ b/drivers/i2c/busses/i2c-sh_mobile.c @@ -119,8 +119,10 @@ struct sh_mobile_i2c_data { struct i2c_adapter adap; struct clk *clk; + u_int8_t icic; u_int8_t iccl; u_int8_t icch; + u_int8_t flags; spinlock_t lock; wait_queue_head_t wait; @@ -129,15 +131,17 @@ struct sh_mobile_i2c_data { int sr; }; +#define IIC_FLAG_HAS_ICIC67 (1 << 0) + #define NORMAL_SPEED 100000 /* FAST_SPEED 400000 */ /* Register offsets */ -#define ICDR(pd) (pd->reg + 0x00) -#define ICCR(pd) (pd->reg + 0x04) -#define ICSR(pd) (pd->reg + 0x08) -#define ICIC(pd) (pd->reg + 0x0c) -#define ICCL(pd) (pd->reg + 0x10) -#define ICCH(pd) (pd->reg + 0x14) +#define ICDR 0x00 +#define ICCR 0x04 +#define ICSR 0x08 +#define ICIC 0x0c +#define ICCL 0x10 +#define ICCH 0x14 /* Register bits */ #define ICCR_ICE 0x80 @@ -155,11 +159,32 @@ struct sh_mobile_i2c_data { #define ICSR_WAIT 0x02 #define ICSR_DTE 0x01 +#define ICIC_ICCLB8 0x80 +#define ICIC_ICCHB8 0x40 #define ICIC_ALE 0x08 #define ICIC_TACKE 0x04 #define ICIC_WAITE 0x02 #define ICIC_DTEE 0x01 +static void iic_wr(struct sh_mobile_i2c_data *pd, int offs, unsigned char data) +{ + if (offs == ICIC) + data |= pd->icic; + + iowrite8(data, pd->reg + offs); +} + +static unsigned char iic_rd(struct sh_mobile_i2c_data *pd, int offs) +{ + return ioread8(pd->reg + offs); +} + +static void iic_set_clr(struct sh_mobile_i2c_data *pd, int offs, + unsigned char set, unsigned char clr) +{ + iic_wr(pd, offs, (iic_rd(pd, offs) | set) & ~clr); +} + static void activate_ch(struct sh_mobile_i2c_data *pd) { unsigned long i2c_clk; @@ -187,6 +212,14 @@ static void activate_ch(struct sh_mobile_i2c_data *pd) else pd->iccl = (u_int8_t)(num/denom); + /* one more bit of ICCL in ICIC */ + if (pd->flags & IIC_FLAG_HAS_ICIC67) { + if ((num/denom) > 0xff) + pd->icic |= ICIC_ICCLB8; + else + pd->icic &= ~ICIC_ICCLB8; + } + /* Calculate the value for icch. From the data sheet: icch = (p clock / transfer rate) * (H / (L + H)) */ num = i2c_clk * 4; @@ -196,25 +229,33 @@ static void activate_ch(struct sh_mobile_i2c_data *pd) else pd->icch = (u_int8_t)(num/denom); + /* one more bit of ICCH in ICIC */ + if (pd->flags & IIC_FLAG_HAS_ICIC67) { + if ((num/denom) > 0xff) + pd->icic |= ICIC_ICCHB8; + else + pd->icic &= ~ICIC_ICCHB8; + } + /* Enable channel and configure rx ack */ - iowrite8(ioread8(ICCR(pd)) | ICCR_ICE, ICCR(pd)); + iic_set_clr(pd, ICCR, ICCR_ICE, 0); /* Mask all interrupts */ - iowrite8(0, ICIC(pd)); + iic_wr(pd, ICIC, 0); /* Set the clock */ - iowrite8(pd->iccl, ICCL(pd)); - iowrite8(pd->icch, ICCH(pd)); + iic_wr(pd, ICCL, pd->iccl); + iic_wr(pd, ICCH, pd->icch); } static void deactivate_ch(struct sh_mobile_i2c_data *pd) { /* Clear/disable interrupts */ - iowrite8(0, ICSR(pd)); - iowrite8(0, ICIC(pd)); + iic_wr(pd, ICSR, 0); + iic_wr(pd, ICIC, 0); /* Disable channel */ - iowrite8(ioread8(ICCR(pd)) & ~ICCR_ICE, ICCR(pd)); + iic_set_clr(pd, ICCR, 0, ICCR_ICE); /* Disable clock and mark device as idle */ clk_disable(pd->clk); @@ -233,35 +274,35 @@ static unsigned char i2c_op(struct sh_mobile_i2c_data *pd, switch (op) { case OP_START: /* issue start and trigger DTE interrupt */ - iowrite8(0x94, ICCR(pd)); + iic_wr(pd, ICCR, 0x94); break; case OP_TX_FIRST: /* disable DTE interrupt and write data */ - iowrite8(ICIC_WAITE | ICIC_ALE | ICIC_TACKE, ICIC(pd)); - iowrite8(data, ICDR(pd)); + iic_wr(pd, ICIC, ICIC_WAITE | ICIC_ALE | ICIC_TACKE); + iic_wr(pd, ICDR, data); break; case OP_TX: /* write data */ - iowrite8(data, ICDR(pd)); + iic_wr(pd, ICDR, data); break; case OP_TX_STOP: /* write data and issue a stop afterwards */ - iowrite8(data, ICDR(pd)); - iowrite8(0x90, ICCR(pd)); + iic_wr(pd, ICDR, data); + iic_wr(pd, ICCR, 0x90); break; case OP_TX_TO_RX: /* select read mode */ - iowrite8(0x81, ICCR(pd)); + iic_wr(pd, ICCR, 0x81); break; case OP_RX: /* just read data */ - ret = ioread8(ICDR(pd)); + ret = iic_rd(pd, ICDR); break; case OP_RX_STOP: /* enable DTE interrupt, issue stop */ - iowrite8(ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE, - ICIC(pd)); - iowrite8(0xc0, ICCR(pd)); + iic_wr(pd, ICIC, + ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE); + iic_wr(pd, ICCR, 0xc0); break; case OP_RX_STOP_DATA: /* enable DTE interrupt, read data, issue stop */ - iowrite8(ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE, - ICIC(pd)); - ret = ioread8(ICDR(pd)); - iowrite8(0xc0, ICCR(pd)); + iic_wr(pd, ICIC, + ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE); + ret = iic_rd(pd, ICDR); + iic_wr(pd, ICCR, 0xc0); break; } @@ -367,7 +408,7 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id) unsigned char sr; int wakeup; - sr = ioread8(ICSR(pd)); + sr = iic_rd(pd, ICSR); pd->sr |= sr; /* remember state */ dev_dbg(pd->dev, "i2c_isr 0x%02x 0x%02x %s %d %d!\n", sr, pd->sr, @@ -376,7 +417,7 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id) if (sr & (ICSR_AL | ICSR_TACK)) { /* don't interrupt transaction - continue to issue stop */ - iowrite8(sr & ~(ICSR_AL | ICSR_TACK), ICSR(pd)); + iic_wr(pd, ICSR, sr & ~(ICSR_AL | ICSR_TACK)); wakeup = 0; } else if (pd->msg->flags & I2C_M_RD) wakeup = sh_mobile_i2c_isr_rx(pd); @@ -384,7 +425,7 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id) wakeup = sh_mobile_i2c_isr_tx(pd); if (sr & ICSR_WAIT) /* TODO: add delay here to support slow acks */ - iowrite8(sr & ~ICSR_WAIT, ICSR(pd)); + iic_wr(pd, ICSR, sr & ~ICSR_WAIT); if (wakeup) { pd->sr |= SW_DONE; @@ -402,21 +443,21 @@ static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg) } /* Initialize channel registers */ - iowrite8(ioread8(ICCR(pd)) & ~ICCR_ICE, ICCR(pd)); + iic_set_clr(pd, ICCR, 0, ICCR_ICE); /* Enable channel and configure rx ack */ - iowrite8(ioread8(ICCR(pd)) | ICCR_ICE, ICCR(pd)); + iic_set_clr(pd, ICCR, ICCR_ICE, 0); /* Set the clock */ - iowrite8(pd->iccl, ICCL(pd)); - iowrite8(pd->icch, ICCH(pd)); + iic_wr(pd, ICCL, pd->iccl); + iic_wr(pd, ICCH, pd->icch); pd->msg = usr_msg; pd->pos = -1; pd->sr = 0; /* Enable all interrupts to begin with */ - iowrite8(ICIC_WAITE | ICIC_ALE | ICIC_TACKE | ICIC_DTEE, ICIC(pd)); + iic_wr(pd, ICIC, ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE); return 0; } @@ -451,7 +492,7 @@ static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter, retry_count = 1000; again: - val = ioread8(ICSR(pd)); + val = iic_rd(pd, ICSR); dev_dbg(pd->dev, "val 0x%02x pd->sr 0x%02x\n", val, pd->sr); @@ -576,6 +617,12 @@ static int sh_mobile_i2c_probe(struct platform_device *dev) goto err_irq; } + /* The IIC blocks on SH-Mobile ARM processors + * come with two new bits in ICIC. + */ + if (size > 0x17) + pd->flags |= IIC_FLAG_HAS_ICIC67; + /* Enable Runtime PM for this device. * * Also tell the Runtime PM core to ignore children diff --git a/drivers/i2c/busses/i2c-viapro.c b/drivers/i2c/busses/i2c-viapro.c index 4c6fff5f330d..0b012f1f8ac5 100644 --- a/drivers/i2c/busses/i2c-viapro.c +++ b/drivers/i2c/busses/i2c-viapro.c @@ -185,14 +185,8 @@ static int vt596_transaction(u8 size) } if (temp & 0x04) { - int read = inb_p(SMBHSTADD) & 0x01; result = -ENXIO; - /* The quick and receive byte commands are used to probe - for chips, so errors are expected, and we don't want - to frighten the user. */ - if (!((size == VT596_QUICK && !read) || - (size == VT596_BYTE && read))) - dev_err(&vt596_adapter.dev, "Transaction error!\n"); + dev_dbg(&vt596_adapter.dev, "No response\n"); } /* Resetting status register */ diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index df937df845eb..d231f683f576 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -20,7 +20,9 @@ /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>. All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl> SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and - Jean Delvare <khali@linux-fr.org> */ + Jean Delvare <khali@linux-fr.org> + Mux support by Rodolfo Giometti <giometti@enneenne.com> and + Michael Lawnick <michael.lawnick.ext@nsn.com> */ #include <linux/module.h> #include <linux/kernel.h> @@ -30,7 +32,6 @@ #include <linux/init.h> #include <linux/idr.h> #include <linux/mutex.h> -#include <linux/of_i2c.h> #include <linux/of_device.h> #include <linux/completion.h> #include <linux/hardirq.h> @@ -195,11 +196,12 @@ static int i2c_device_pm_suspend(struct device *dev) { const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - if (pm_runtime_suspended(dev)) - return 0; - - if (pm) - return pm->suspend ? pm->suspend(dev) : 0; + if (pm) { + if (pm_runtime_suspended(dev)) + return 0; + else + return pm->suspend ? pm->suspend(dev) : 0; + } return i2c_legacy_suspend(dev, PMSG_SUSPEND); } @@ -214,12 +216,6 @@ static int i2c_device_pm_resume(struct device *dev) else ret = i2c_legacy_resume(dev); - if (!ret) { - pm_runtime_disable(dev); - pm_runtime_set_active(dev); - pm_runtime_enable(dev); - } - return ret; } @@ -227,11 +223,12 @@ static int i2c_device_pm_freeze(struct device *dev) { const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - if (pm_runtime_suspended(dev)) - return 0; - - if (pm) - return pm->freeze ? pm->freeze(dev) : 0; + if (pm) { + if (pm_runtime_suspended(dev)) + return 0; + else + return pm->freeze ? pm->freeze(dev) : 0; + } return i2c_legacy_suspend(dev, PMSG_FREEZE); } @@ -240,11 +237,12 @@ static int i2c_device_pm_thaw(struct device *dev) { const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - if (pm_runtime_suspended(dev)) - return 0; - - if (pm) - return pm->thaw ? pm->thaw(dev) : 0; + if (pm) { + if (pm_runtime_suspended(dev)) + return 0; + else + return pm->thaw ? pm->thaw(dev) : 0; + } return i2c_legacy_resume(dev); } @@ -253,11 +251,12 @@ static int i2c_device_pm_poweroff(struct device *dev) { const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - if (pm_runtime_suspended(dev)) - return 0; - - if (pm) - return pm->poweroff ? pm->poweroff(dev) : 0; + if (pm) { + if (pm_runtime_suspended(dev)) + return 0; + else + return pm->poweroff ? pm->poweroff(dev) : 0; + } return i2c_legacy_suspend(dev, PMSG_HIBERNATE); } @@ -423,13 +422,95 @@ static int __i2c_check_addr_busy(struct device *dev, void *addrp) return 0; } +/* walk up mux tree */ +static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr) +{ + struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); + int result; + + result = device_for_each_child(&adapter->dev, &addr, + __i2c_check_addr_busy); + + if (!result && parent) + result = i2c_check_mux_parents(parent, addr); + + return result; +} + +/* recurse down mux tree */ +static int i2c_check_mux_children(struct device *dev, void *addrp) +{ + int result; + + if (dev->type == &i2c_adapter_type) + result = device_for_each_child(dev, addrp, + i2c_check_mux_children); + else + result = __i2c_check_addr_busy(dev, addrp); + + return result; +} + static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr) { - return device_for_each_child(&adapter->dev, &addr, - __i2c_check_addr_busy); + struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); + int result = 0; + + if (parent) + result = i2c_check_mux_parents(parent, addr); + + if (!result) + result = device_for_each_child(&adapter->dev, &addr, + i2c_check_mux_children); + + return result; +} + +/** + * i2c_lock_adapter - Get exclusive access to an I2C bus segment + * @adapter: Target I2C bus segment + */ +void i2c_lock_adapter(struct i2c_adapter *adapter) +{ + struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); + + if (parent) + i2c_lock_adapter(parent); + else + rt_mutex_lock(&adapter->bus_lock); +} +EXPORT_SYMBOL_GPL(i2c_lock_adapter); + +/** + * i2c_trylock_adapter - Try to get exclusive access to an I2C bus segment + * @adapter: Target I2C bus segment + */ +static int i2c_trylock_adapter(struct i2c_adapter *adapter) +{ + struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); + + if (parent) + return i2c_trylock_adapter(parent); + else + return rt_mutex_trylock(&adapter->bus_lock); } /** + * i2c_unlock_adapter - Release exclusive access to an I2C bus segment + * @adapter: Target I2C bus segment + */ +void i2c_unlock_adapter(struct i2c_adapter *adapter) +{ + struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); + + if (parent) + i2c_unlock_adapter(parent); + else + rt_mutex_unlock(&adapter->bus_lock); +} +EXPORT_SYMBOL_GPL(i2c_unlock_adapter); + +/** * i2c_new_device - instantiate an i2c device * @adap: the adapter managing the device * @info: describes one I2C device; bus_num is ignored @@ -602,8 +683,6 @@ i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr, char *blank, end; int res; - dev_warn(dev, "The new_device interface is still experimental " - "and may change in a near future\n"); memset(&info, 0, sizeof(struct i2c_board_info)); blank = strchr(buf, ' '); @@ -633,9 +712,9 @@ i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr, return -EINVAL; /* Keep track of the added device */ - i2c_lock_adapter(adap); + mutex_lock(&adap->userspace_clients_lock); list_add_tail(&client->detected, &adap->userspace_clients); - i2c_unlock_adapter(adap); + mutex_unlock(&adap->userspace_clients_lock); dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", info.type, info.addr); @@ -674,7 +753,7 @@ i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr, /* Make sure the device was added through sysfs */ res = -ENOENT; - i2c_lock_adapter(adap); + mutex_lock(&adap->userspace_clients_lock); list_for_each_entry_safe(client, next, &adap->userspace_clients, detected) { if (client->addr == addr) { @@ -687,7 +766,7 @@ i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr, break; } } - i2c_unlock_adapter(adap); + mutex_unlock(&adap->userspace_clients_lock); if (res < 0) dev_err(dev, "%s: Can't find device in list\n", @@ -714,10 +793,11 @@ static const struct attribute_group *i2c_adapter_attr_groups[] = { NULL }; -static struct device_type i2c_adapter_type = { +struct device_type i2c_adapter_type = { .groups = i2c_adapter_attr_groups, .release = i2c_adapter_dev_release, }; +EXPORT_SYMBOL_GPL(i2c_adapter_type); #ifdef CONFIG_I2C_COMPAT static struct class_compat *i2c_adapter_compat_class; @@ -760,7 +840,7 @@ static int __process_new_adapter(struct device_driver *d, void *data) static int i2c_register_adapter(struct i2c_adapter *adap) { - int res = 0, dummy; + int res = 0; /* Can't register until after driver model init */ if (unlikely(WARN_ON(!i2c_bus_type.p))) { @@ -769,6 +849,7 @@ static int i2c_register_adapter(struct i2c_adapter *adap) } rt_mutex_init(&adap->bus_lock); + mutex_init(&adap->userspace_clients_lock); INIT_LIST_HEAD(&adap->userspace_clients); /* Set default timeout to 1 second if not already set */ @@ -796,13 +877,9 @@ static int i2c_register_adapter(struct i2c_adapter *adap) if (adap->nr < __i2c_first_dynamic_bus_num) i2c_scan_static_board_info(adap); - /* Register devices from the device tree */ - of_i2c_register_devices(adap); - /* Notify drivers */ mutex_lock(&core_lock); - dummy = bus_for_each_drv(&i2c_bus_type, NULL, adap, - __process_new_adapter); + bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); mutex_unlock(&core_lock); return 0; @@ -975,7 +1052,7 @@ int i2c_del_adapter(struct i2c_adapter *adap) return res; /* Remove devices instantiated from sysfs */ - i2c_lock_adapter(adap); + mutex_lock(&adap->userspace_clients_lock); list_for_each_entry_safe(client, next, &adap->userspace_clients, detected) { dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, @@ -983,7 +1060,7 @@ int i2c_del_adapter(struct i2c_adapter *adap) list_del(&client->detected); i2c_unregister_device(client); } - i2c_unlock_adapter(adap); + mutex_unlock(&adap->userspace_clients_lock); /* Detach any active clients. This can't fail, thus we do not checking the returned value. */ @@ -1238,12 +1315,12 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) #endif if (in_atomic() || irqs_disabled()) { - ret = rt_mutex_trylock(&adap->bus_lock); + ret = i2c_trylock_adapter(adap); if (!ret) /* I2C activity is ongoing. */ return -EAGAIN; } else { - rt_mutex_lock(&adap->bus_lock); + i2c_lock_adapter(adap); } /* Retry automatically on arbitration loss */ @@ -1255,7 +1332,7 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) if (time_after(jiffies, orig_jiffies + adap->timeout)) break; } - rt_mutex_unlock(&adap->bus_lock); + i2c_unlock_adapter(adap); return ret; } else { @@ -1350,13 +1427,17 @@ static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr) I2C_SMBUS_BYTE_DATA, &dummy); else #endif - if ((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50 - || !i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) - err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, - I2C_SMBUS_BYTE, &dummy); - else + if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50) + && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0, I2C_SMBUS_QUICK, NULL); + else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) + err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, + I2C_SMBUS_BYTE, &dummy); + else { + dev_warn(&adap->dev, "No suitable probing method supported\n"); + err = -EOPNOTSUPP; + } return err >= 0; } @@ -1427,52 +1508,46 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) if (!driver->detect || !address_list) return 0; + /* Stop here if the classes do not match */ + if (!(adapter->class & driver->class)) + return 0; + /* Set up a temporary client to help detect callback */ temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); if (!temp_client) return -ENOMEM; temp_client->adapter = adapter; - /* Stop here if the classes do not match */ - if (!(adapter->class & driver->class)) - goto exit_free; - - /* Stop here if the bus doesn't support probing */ - if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE)) { - if (address_list[0] == I2C_CLIENT_END) - goto exit_free; - - dev_warn(&adapter->dev, "Probing not supported\n"); - err = -EOPNOTSUPP; - goto exit_free; - } - for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) { dev_dbg(&adapter->dev, "found normal entry for adapter %d, " "addr 0x%02x\n", adap_id, address_list[i]); temp_client->addr = address_list[i]; err = i2c_detect_address(temp_client, driver); - if (err) - goto exit_free; + if (unlikely(err)) + break; } - exit_free: kfree(temp_client); return err; } +int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr) +{ + return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, + I2C_SMBUS_QUICK, NULL) >= 0; +} +EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read); + struct i2c_client * i2c_new_probed_device(struct i2c_adapter *adap, struct i2c_board_info *info, - unsigned short const *addr_list) + unsigned short const *addr_list, + int (*probe)(struct i2c_adapter *, unsigned short addr)) { int i; - /* Stop here if the bus doesn't support probing */ - if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) { - dev_err(&adap->dev, "Probing not supported\n"); - return NULL; - } + if (!probe) + probe = i2c_default_probe; for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { /* Check address validity */ @@ -1490,7 +1565,7 @@ i2c_new_probed_device(struct i2c_adapter *adap, } /* Test address responsiveness */ - if (i2c_default_probe(adap, addr_list[i])) + if (probe(adap, addr_list[i])) break; } @@ -2002,7 +2077,7 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, flags &= I2C_M_TEN | I2C_CLIENT_PEC; if (adapter->algo->smbus_xfer) { - rt_mutex_lock(&adapter->bus_lock); + i2c_lock_adapter(adapter); /* Retry automatically on arbitration loss */ orig_jiffies = jiffies; @@ -2016,7 +2091,7 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, orig_jiffies + adapter->timeout)) break; } - rt_mutex_unlock(&adapter->bus_lock); + i2c_unlock_adapter(adapter); } else res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write, command, protocol, data); diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c index e0694e4d86c7..cec0f3ba97f8 100644 --- a/drivers/i2c/i2c-dev.c +++ b/drivers/i2c/i2c-dev.c @@ -167,13 +167,9 @@ static ssize_t i2cdev_write(struct file *file, const char __user *buf, if (count > 8192) count = 8192; - tmp = kmalloc(count, GFP_KERNEL); - if (tmp == NULL) - return -ENOMEM; - if (copy_from_user(tmp, buf, count)) { - kfree(tmp); - return -EFAULT; - } + tmp = memdup_user(buf, count); + if (IS_ERR(tmp)) + return PTR_ERR(tmp); pr_debug("i2c-dev: i2c-%d writing %zu bytes.\n", iminor(file->f_path.dentry->d_inode), count); @@ -193,12 +189,49 @@ static int i2cdev_check(struct device *dev, void *addrp) return dev->driver ? -EBUSY : 0; } +/* walk up mux tree */ +static int i2cdev_check_mux_parents(struct i2c_adapter *adapter, int addr) +{ + struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); + int result; + + result = device_for_each_child(&adapter->dev, &addr, i2cdev_check); + if (!result && parent) + result = i2cdev_check_mux_parents(parent, addr); + + return result; +} + +/* recurse down mux tree */ +static int i2cdev_check_mux_children(struct device *dev, void *addrp) +{ + int result; + + if (dev->type == &i2c_adapter_type) + result = device_for_each_child(dev, addrp, + i2cdev_check_mux_children); + else + result = i2cdev_check(dev, addrp); + + return result; +} + /* This address checking function differs from the one in i2c-core in that it considers an address with a registered device, but no driver bound to it, as NOT busy. */ static int i2cdev_check_addr(struct i2c_adapter *adapter, unsigned int addr) { - return device_for_each_child(&adapter->dev, &addr, i2cdev_check); + struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); + int result = 0; + + if (parent) + result = i2cdev_check_mux_parents(parent, addr); + + if (!result) + result = device_for_each_child(&adapter->dev, &addr, + i2cdev_check_mux_children); + + return result; } static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client, @@ -219,9 +252,7 @@ static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client, if (rdwr_arg.nmsgs > I2C_RDRW_IOCTL_MAX_MSGS) return -EINVAL; - rdwr_pa = (struct i2c_msg *) - kmalloc(rdwr_arg.nmsgs * sizeof(struct i2c_msg), - GFP_KERNEL); + rdwr_pa = kmalloc(rdwr_arg.nmsgs * sizeof(struct i2c_msg), GFP_KERNEL); if (!rdwr_pa) return -ENOMEM; @@ -247,15 +278,9 @@ static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client, break; } data_ptrs[i] = (u8 __user *)rdwr_pa[i].buf; - rdwr_pa[i].buf = kmalloc(rdwr_pa[i].len, GFP_KERNEL); - if (rdwr_pa[i].buf == NULL) { - res = -ENOMEM; - break; - } - if (copy_from_user(rdwr_pa[i].buf, data_ptrs[i], - rdwr_pa[i].len)) { - ++i; /* Needs to be kfreed too */ - res = -EFAULT; + rdwr_pa[i].buf = memdup_user(data_ptrs[i], rdwr_pa[i].len); + if (IS_ERR(rdwr_pa[i].buf)) { + res = PTR_ERR(rdwr_pa[i].buf); break; } } diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c new file mode 100644 index 000000000000..d32a4843fc3a --- /dev/null +++ b/drivers/i2c/i2c-mux.c @@ -0,0 +1,165 @@ +/* + * Multiplexed I2C bus driver. + * + * Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it> + * Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it> + * Copyright (c) 2009-2010 NSN GmbH & Co KG <michael.lawnick.ext@nsn.com> + * + * Simplifies access to complex multiplexed I2C bus topologies, by presenting + * each multiplexed bus segment as an additional I2C adapter. + * Supports multi-level mux'ing (mux behind a mux). + * + * Based on: + * i2c-virt.c from Kumar Gala <galak@kernel.crashing.org> + * i2c-virtual.c from Ken Harrenstien, Copyright (c) 2004 Google, Inc. + * i2c-virtual.c from Brian Kuschak <bkuschak@yahoo.com> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/i2c.h> +#include <linux/i2c-mux.h> + +/* multiplexer per channel data */ +struct i2c_mux_priv { + struct i2c_adapter adap; + struct i2c_algorithm algo; + + struct i2c_adapter *parent; + void *mux_dev; /* the mux chip/device */ + u32 chan_id; /* the channel id */ + + int (*select)(struct i2c_adapter *, void *mux_dev, u32 chan_id); + int (*deselect)(struct i2c_adapter *, void *mux_dev, u32 chan_id); +}; + +static int i2c_mux_master_xfer(struct i2c_adapter *adap, + struct i2c_msg msgs[], int num) +{ + struct i2c_mux_priv *priv = adap->algo_data; + struct i2c_adapter *parent = priv->parent; + int ret; + + /* Switch to the right mux port and perform the transfer. */ + + ret = priv->select(parent, priv->mux_dev, priv->chan_id); + if (ret >= 0) + ret = parent->algo->master_xfer(parent, msgs, num); + if (priv->deselect) + priv->deselect(parent, priv->mux_dev, priv->chan_id); + + return ret; +} + +static int i2c_mux_smbus_xfer(struct i2c_adapter *adap, + u16 addr, unsigned short flags, + char read_write, u8 command, + int size, union i2c_smbus_data *data) +{ + struct i2c_mux_priv *priv = adap->algo_data; + struct i2c_adapter *parent = priv->parent; + int ret; + + /* Select the right mux port and perform the transfer. */ + + ret = priv->select(parent, priv->mux_dev, priv->chan_id); + if (ret >= 0) + ret = parent->algo->smbus_xfer(parent, addr, flags, + read_write, command, size, data); + if (priv->deselect) + priv->deselect(parent, priv->mux_dev, priv->chan_id); + + return ret; +} + +/* Return the parent's functionality */ +static u32 i2c_mux_functionality(struct i2c_adapter *adap) +{ + struct i2c_mux_priv *priv = adap->algo_data; + struct i2c_adapter *parent = priv->parent; + + return parent->algo->functionality(parent); +} + +struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent, + void *mux_dev, u32 force_nr, u32 chan_id, + int (*select) (struct i2c_adapter *, + void *, u32), + int (*deselect) (struct i2c_adapter *, + void *, u32)) +{ + struct i2c_mux_priv *priv; + int ret; + + priv = kzalloc(sizeof(struct i2c_mux_priv), GFP_KERNEL); + if (!priv) + return NULL; + + /* Set up private adapter data */ + priv->parent = parent; + priv->mux_dev = mux_dev; + priv->chan_id = chan_id; + priv->select = select; + priv->deselect = deselect; + + /* Need to do algo dynamically because we don't know ahead + * of time what sort of physical adapter we'll be dealing with. + */ + if (parent->algo->master_xfer) + priv->algo.master_xfer = i2c_mux_master_xfer; + if (parent->algo->smbus_xfer) + priv->algo.smbus_xfer = i2c_mux_smbus_xfer; + priv->algo.functionality = i2c_mux_functionality; + + /* Now fill out new adapter structure */ + snprintf(priv->adap.name, sizeof(priv->adap.name), + "i2c-%d-mux (chan_id %d)", i2c_adapter_id(parent), chan_id); + priv->adap.owner = THIS_MODULE; + priv->adap.id = parent->id; + priv->adap.algo = &priv->algo; + priv->adap.algo_data = priv; + priv->adap.dev.parent = &parent->dev; + + if (force_nr) { + priv->adap.nr = force_nr; + ret = i2c_add_numbered_adapter(&priv->adap); + } else { + ret = i2c_add_adapter(&priv->adap); + } + if (ret < 0) { + dev_err(&parent->dev, + "failed to add mux-adapter (error=%d)\n", + ret); + kfree(priv); + return NULL; + } + + dev_info(&parent->dev, "Added multiplexed i2c bus %d\n", + i2c_adapter_id(&priv->adap)); + + return &priv->adap; +} +EXPORT_SYMBOL_GPL(i2c_add_mux_adapter); + +int i2c_del_mux_adapter(struct i2c_adapter *adap) +{ + struct i2c_mux_priv *priv = adap->algo_data; + int ret; + + ret = i2c_del_adapter(adap); + if (ret < 0) + return ret; + kfree(priv); + + return 0; +} +EXPORT_SYMBOL_GPL(i2c_del_mux_adapter); + +MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>"); +MODULE_DESCRIPTION("I2C driver for multiplexed I2C busses"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/muxes/Kconfig b/drivers/i2c/muxes/Kconfig new file mode 100644 index 000000000000..4d91d80bfd23 --- /dev/null +++ b/drivers/i2c/muxes/Kconfig @@ -0,0 +1,28 @@ +# +# Multiplexer I2C chip drivers configuration +# + +menu "Multiplexer I2C Chip support" + depends on I2C_MUX + +config I2C_MUX_PCA9541 + tristate "NXP PCA9541 I2C Master Selector" + depends on EXPERIMENTAL + help + If you say yes here you get support for the NXP PCA9541 + I2C Master Selector. + + This driver can also be built as a module. If so, the module + will be called pca9541. + +config I2C_MUX_PCA954x + tristate "Philips PCA954x I2C Mux/switches" + depends on EXPERIMENTAL + help + If you say yes here you get support for the Philips PCA954x + I2C mux/switch devices. + + This driver can also be built as a module. If so, the module + will be called pca954x. + +endmenu diff --git a/drivers/i2c/muxes/Makefile b/drivers/i2c/muxes/Makefile new file mode 100644 index 000000000000..d743806d9b42 --- /dev/null +++ b/drivers/i2c/muxes/Makefile @@ -0,0 +1,7 @@ +# +# Makefile for multiplexer I2C chip drivers. + +obj-$(CONFIG_I2C_MUX_PCA9541) += pca9541.o +obj-$(CONFIG_I2C_MUX_PCA954x) += pca954x.o + +ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG diff --git a/drivers/i2c/muxes/pca9541.c b/drivers/i2c/muxes/pca9541.c new file mode 100644 index 000000000000..ed699c5aa79d --- /dev/null +++ b/drivers/i2c/muxes/pca9541.c @@ -0,0 +1,411 @@ +/* + * I2C multiplexer driver for PCA9541 bus master selector + * + * Copyright (c) 2010 Ericsson AB. + * + * Author: Guenter Roeck <guenter.roeck@ericsson.com> + * + * Derived from: + * pca954x.c + * + * Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it> + * Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/jiffies.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/device.h> +#include <linux/i2c.h> +#include <linux/i2c-mux.h> + +#include <linux/i2c/pca954x.h> + +/* + * The PCA9541 is a bus master selector. It supports two I2C masters connected + * to a single slave bus. + * + * Before each bus transaction, a master has to acquire bus ownership. After the + * transaction is complete, bus ownership has to be released. This fits well + * into the I2C multiplexer framework, which provides select and release + * functions for this purpose. For this reason, this driver is modeled as + * single-channel I2C bus multiplexer. + * + * This driver assumes that the two bus masters are controlled by two different + * hosts. If a single host controls both masters, platform code has to ensure + * that only one of the masters is instantiated at any given time. + */ + +#define PCA9541_CONTROL 0x01 +#define PCA9541_ISTAT 0x02 + +#define PCA9541_CTL_MYBUS (1 << 0) +#define PCA9541_CTL_NMYBUS (1 << 1) +#define PCA9541_CTL_BUSON (1 << 2) +#define PCA9541_CTL_NBUSON (1 << 3) +#define PCA9541_CTL_BUSINIT (1 << 4) +#define PCA9541_CTL_TESTON (1 << 6) +#define PCA9541_CTL_NTESTON (1 << 7) + +#define PCA9541_ISTAT_INTIN (1 << 0) +#define PCA9541_ISTAT_BUSINIT (1 << 1) +#define PCA9541_ISTAT_BUSOK (1 << 2) +#define PCA9541_ISTAT_BUSLOST (1 << 3) +#define PCA9541_ISTAT_MYTEST (1 << 6) +#define PCA9541_ISTAT_NMYTEST (1 << 7) + +#define BUSON (PCA9541_CTL_BUSON | PCA9541_CTL_NBUSON) +#define MYBUS (PCA9541_CTL_MYBUS | PCA9541_CTL_NMYBUS) +#define mybus(x) (!((x) & MYBUS) || ((x) & MYBUS) == MYBUS) +#define busoff(x) (!((x) & BUSON) || ((x) & BUSON) == BUSON) + +/* arbitration timeouts, in jiffies */ +#define ARB_TIMEOUT (HZ / 8) /* 125 ms until forcing bus ownership */ +#define ARB2_TIMEOUT (HZ / 4) /* 250 ms until acquisition failure */ + +/* arbitration retry delays, in us */ +#define SELECT_DELAY_SHORT 50 +#define SELECT_DELAY_LONG 1000 + +struct pca9541 { + struct i2c_adapter *mux_adap; + unsigned long select_timeout; + unsigned long arb_timeout; +}; + +static const struct i2c_device_id pca9541_id[] = { + {"pca9541", 0}, + {} +}; + +MODULE_DEVICE_TABLE(i2c, pca9541_id); + +/* + * Write to chip register. Don't use i2c_transfer()/i2c_smbus_xfer() + * as they will try to lock the adapter a second time. + */ +static int pca9541_reg_write(struct i2c_client *client, u8 command, u8 val) +{ + struct i2c_adapter *adap = client->adapter; + int ret; + + if (adap->algo->master_xfer) { + struct i2c_msg msg; + char buf[2]; + + msg.addr = client->addr; + msg.flags = 0; + msg.len = 2; + buf[0] = command; + buf[1] = val; + msg.buf = buf; + ret = adap->algo->master_xfer(adap, &msg, 1); + } else { + union i2c_smbus_data data; + + data.byte = val; + ret = adap->algo->smbus_xfer(adap, client->addr, + client->flags, + I2C_SMBUS_WRITE, + command, + I2C_SMBUS_BYTE_DATA, &data); + } + + return ret; +} + +/* + * Read from chip register. Don't use i2c_transfer()/i2c_smbus_xfer() + * as they will try to lock adapter a second time. + */ +static int pca9541_reg_read(struct i2c_client *client, u8 command) +{ + struct i2c_adapter *adap = client->adapter; + int ret; + u8 val; + + if (adap->algo->master_xfer) { + struct i2c_msg msg[2] = { + { + .addr = client->addr, + .flags = 0, + .len = 1, + .buf = &command + }, + { + .addr = client->addr, + .flags = I2C_M_RD, + .len = 1, + .buf = &val + } + }; + ret = adap->algo->master_xfer(adap, msg, 2); + if (ret == 2) + ret = val; + else if (ret >= 0) + ret = -EIO; + } else { + union i2c_smbus_data data; + + ret = adap->algo->smbus_xfer(adap, client->addr, + client->flags, + I2C_SMBUS_READ, + command, + I2C_SMBUS_BYTE_DATA, &data); + if (!ret) + ret = data.byte; + } + return ret; +} + +/* + * Arbitration management functions + */ + +/* Release bus. Also reset NTESTON and BUSINIT if it was set. */ +static void pca9541_release_bus(struct i2c_client *client) +{ + int reg; + + reg = pca9541_reg_read(client, PCA9541_CONTROL); + if (reg >= 0 && !busoff(reg) && mybus(reg)) + pca9541_reg_write(client, PCA9541_CONTROL, + (reg & PCA9541_CTL_NBUSON) >> 1); +} + +/* + * Arbitration is defined as a two-step process. A bus master can only activate + * the slave bus if it owns it; otherwise it has to request ownership first. + * This multi-step process ensures that access contention is resolved + * gracefully. + * + * Bus Ownership Other master Action + * state requested access + * ---------------------------------------------------- + * off - yes wait for arbitration timeout or + * for other master to drop request + * off no no take ownership + * off yes no turn on bus + * on yes - done + * on no - wait for arbitration timeout or + * for other master to release bus + * + * The main contention point occurs if the slave bus is off and both masters + * request ownership at the same time. In this case, one master will turn on + * the slave bus, believing that it owns it. The other master will request + * bus ownership. Result is that the bus is turned on, and master which did + * _not_ own the slave bus before ends up owning it. + */ + +/* Control commands per PCA9541 datasheet */ +static const u8 pca9541_control[16] = { + 4, 0, 1, 5, 4, 4, 5, 5, 0, 0, 1, 1, 0, 4, 5, 1 +}; + +/* + * Channel arbitration + * + * Return values: + * <0: error + * 0 : bus not acquired + * 1 : bus acquired + */ +static int pca9541_arbitrate(struct i2c_client *client) +{ + struct pca9541 *data = i2c_get_clientdata(client); + int reg; + + reg = pca9541_reg_read(client, PCA9541_CONTROL); + if (reg < 0) + return reg; + + if (busoff(reg)) { + int istat; + /* + * Bus is off. Request ownership or turn it on unless + * other master requested ownership. + */ + istat = pca9541_reg_read(client, PCA9541_ISTAT); + if (!(istat & PCA9541_ISTAT_NMYTEST) + || time_is_before_eq_jiffies(data->arb_timeout)) { + /* + * Other master did not request ownership, + * or arbitration timeout expired. Take the bus. + */ + pca9541_reg_write(client, + PCA9541_CONTROL, + pca9541_control[reg & 0x0f] + | PCA9541_CTL_NTESTON); + data->select_timeout = SELECT_DELAY_SHORT; + } else { + /* + * Other master requested ownership. + * Set extra long timeout to give it time to acquire it. + */ + data->select_timeout = SELECT_DELAY_LONG * 2; + } + } else if (mybus(reg)) { + /* + * Bus is on, and we own it. We are done with acquisition. + * Reset NTESTON and BUSINIT, then return success. + */ + if (reg & (PCA9541_CTL_NTESTON | PCA9541_CTL_BUSINIT)) + pca9541_reg_write(client, + PCA9541_CONTROL, + reg & ~(PCA9541_CTL_NTESTON + | PCA9541_CTL_BUSINIT)); + return 1; + } else { + /* + * Other master owns the bus. + * If arbitration timeout has expired, force ownership. + * Otherwise request it. + */ + data->select_timeout = SELECT_DELAY_LONG; + if (time_is_before_eq_jiffies(data->arb_timeout)) { + /* Time is up, take the bus and reset it. */ + pca9541_reg_write(client, + PCA9541_CONTROL, + pca9541_control[reg & 0x0f] + | PCA9541_CTL_BUSINIT + | PCA9541_CTL_NTESTON); + } else { + /* Request bus ownership if needed */ + if (!(reg & PCA9541_CTL_NTESTON)) + pca9541_reg_write(client, + PCA9541_CONTROL, + reg | PCA9541_CTL_NTESTON); + } + } + return 0; +} + +static int pca9541_select_chan(struct i2c_adapter *adap, void *client, u32 chan) +{ + struct pca9541 *data = i2c_get_clientdata(client); + int ret; + unsigned long timeout = jiffies + ARB2_TIMEOUT; + /* give up after this time */ + + data->arb_timeout = jiffies + ARB_TIMEOUT; + /* force bus ownership after this time */ + + do { + ret = pca9541_arbitrate(client); + if (ret) + return ret < 0 ? ret : 0; + + if (data->select_timeout == SELECT_DELAY_SHORT) + udelay(data->select_timeout); + else + msleep(data->select_timeout / 1000); + } while (time_is_after_eq_jiffies(timeout)); + + return -ETIMEDOUT; +} + +static int pca9541_release_chan(struct i2c_adapter *adap, + void *client, u32 chan) +{ + pca9541_release_bus(client); + return 0; +} + +/* + * I2C init/probing/exit functions + */ +static int pca9541_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct i2c_adapter *adap = client->adapter; + struct pca954x_platform_data *pdata = client->dev.platform_data; + struct pca9541 *data; + int force; + int ret = -ENODEV; + + if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE_DATA)) + goto err; + + data = kzalloc(sizeof(struct pca9541), GFP_KERNEL); + if (!data) { + ret = -ENOMEM; + goto err; + } + + i2c_set_clientdata(client, data); + + /* + * I2C accesses are unprotected here. + * We have to lock the adapter before releasing the bus. + */ + i2c_lock_adapter(adap); + pca9541_release_bus(client); + i2c_unlock_adapter(adap); + + /* Create mux adapter */ + + force = 0; + if (pdata) + force = pdata->modes[0].adap_id; + data->mux_adap = i2c_add_mux_adapter(adap, client, force, 0, + pca9541_select_chan, + pca9541_release_chan); + + if (data->mux_adap == NULL) { + dev_err(&client->dev, "failed to register master selector\n"); + goto exit_free; + } + + dev_info(&client->dev, "registered master selector for I2C %s\n", + client->name); + + return 0; + +exit_free: + kfree(data); +err: + return ret; +} + +static int pca9541_remove(struct i2c_client *client) +{ + struct pca9541 *data = i2c_get_clientdata(client); + + i2c_del_mux_adapter(data->mux_adap); + + kfree(data); + return 0; +} + +static struct i2c_driver pca9541_driver = { + .driver = { + .name = "pca9541", + .owner = THIS_MODULE, + }, + .probe = pca9541_probe, + .remove = pca9541_remove, + .id_table = pca9541_id, +}; + +static int __init pca9541_init(void) +{ + return i2c_add_driver(&pca9541_driver); +} + +static void __exit pca9541_exit(void) +{ + i2c_del_driver(&pca9541_driver); +} + +module_init(pca9541_init); +module_exit(pca9541_exit); + +MODULE_AUTHOR("Guenter Roeck <guenter.roeck@ericsson.com>"); +MODULE_DESCRIPTION("PCA9541 I2C master selector driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/muxes/pca954x.c b/drivers/i2c/muxes/pca954x.c new file mode 100644 index 000000000000..54e1ce73534b --- /dev/null +++ b/drivers/i2c/muxes/pca954x.c @@ -0,0 +1,301 @@ +/* + * I2C multiplexer + * + * Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it> + * Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it> + * + * This module supports the PCA954x series of I2C multiplexer/switch chips + * made by Philips Semiconductors. + * This includes the: + * PCA9540, PCA9542, PCA9543, PCA9544, PCA9545, PCA9546, PCA9547 + * and PCA9548. + * + * These chips are all controlled via the I2C bus itself, and all have a + * single 8-bit register. The upstream "parent" bus fans out to two, + * four, or eight downstream busses or channels; which of these + * are selected is determined by the chip type and register contents. A + * mux can select only one sub-bus at a time; a switch can select any + * combination simultaneously. + * + * Based on: + * pca954x.c from Kumar Gala <galak@kernel.crashing.org> + * Copyright (C) 2006 + * + * Based on: + * pca954x.c from Ken Harrenstien + * Copyright (C) 2004 Google, Inc. (Ken Harrenstien) + * + * Based on: + * i2c-virtual_cb.c from Brian Kuschak <bkuschak@yahoo.com> + * and + * pca9540.c from Jean Delvare <khali@linux-fr.org>. + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/device.h> +#include <linux/i2c.h> +#include <linux/i2c-mux.h> + +#include <linux/i2c/pca954x.h> + +#define PCA954X_MAX_NCHANS 8 + +enum pca_type { + pca_9540, + pca_9542, + pca_9543, + pca_9544, + pca_9545, + pca_9546, + pca_9547, + pca_9548, +}; + +struct pca954x { + enum pca_type type; + struct i2c_adapter *virt_adaps[PCA954X_MAX_NCHANS]; + + u8 last_chan; /* last register value */ +}; + +struct chip_desc { + u8 nchans; + u8 enable; /* used for muxes only */ + enum muxtype { + pca954x_ismux = 0, + pca954x_isswi + } muxtype; +}; + +/* Provide specs for the PCA954x types we know about */ +static const struct chip_desc chips[] = { + [pca_9540] = { + .nchans = 2, + .enable = 0x4, + .muxtype = pca954x_ismux, + }, + [pca_9543] = { + .nchans = 2, + .muxtype = pca954x_isswi, + }, + [pca_9544] = { + .nchans = 4, + .enable = 0x4, + .muxtype = pca954x_ismux, + }, + [pca_9545] = { + .nchans = 4, + .muxtype = pca954x_isswi, + }, + [pca_9547] = { + .nchans = 8, + .enable = 0x8, + .muxtype = pca954x_ismux, + }, + [pca_9548] = { + .nchans = 8, + .muxtype = pca954x_isswi, + }, +}; + +static const struct i2c_device_id pca954x_id[] = { + { "pca9540", pca_9540 }, + { "pca9542", pca_9540 }, + { "pca9543", pca_9543 }, + { "pca9544", pca_9544 }, + { "pca9545", pca_9545 }, + { "pca9546", pca_9545 }, + { "pca9547", pca_9547 }, + { "pca9548", pca_9548 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, pca954x_id); + +/* Write to mux register. Don't use i2c_transfer()/i2c_smbus_xfer() + for this as they will try to lock adapter a second time */ +static int pca954x_reg_write(struct i2c_adapter *adap, + struct i2c_client *client, u8 val) +{ + int ret = -ENODEV; + + if (adap->algo->master_xfer) { + struct i2c_msg msg; + char buf[1]; + + msg.addr = client->addr; + msg.flags = 0; + msg.len = 1; + buf[0] = val; + msg.buf = buf; + ret = adap->algo->master_xfer(adap, &msg, 1); + } else { + union i2c_smbus_data data; + ret = adap->algo->smbus_xfer(adap, client->addr, + client->flags, + I2C_SMBUS_WRITE, + val, I2C_SMBUS_BYTE, &data); + } + + return ret; +} + +static int pca954x_select_chan(struct i2c_adapter *adap, + void *client, u32 chan) +{ + struct pca954x *data = i2c_get_clientdata(client); + const struct chip_desc *chip = &chips[data->type]; + u8 regval; + int ret = 0; + + /* we make switches look like muxes, not sure how to be smarter */ + if (chip->muxtype == pca954x_ismux) + regval = chan | chip->enable; + else + regval = 1 << chan; + + /* Only select the channel if its different from the last channel */ + if (data->last_chan != regval) { + ret = pca954x_reg_write(adap, client, regval); + data->last_chan = regval; + } + + return ret; +} + +static int pca954x_deselect_mux(struct i2c_adapter *adap, + void *client, u32 chan) +{ + struct pca954x *data = i2c_get_clientdata(client); + + /* Deselect active channel */ + data->last_chan = 0; + return pca954x_reg_write(adap, client, data->last_chan); +} + +/* + * I2C init/probing/exit functions + */ +static int pca954x_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct i2c_adapter *adap = to_i2c_adapter(client->dev.parent); + struct pca954x_platform_data *pdata = client->dev.platform_data; + int num, force; + struct pca954x *data; + int ret = -ENODEV; + + if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE)) + goto err; + + data = kzalloc(sizeof(struct pca954x), GFP_KERNEL); + if (!data) { + ret = -ENOMEM; + goto err; + } + + i2c_set_clientdata(client, data); + + /* Read the mux register at addr to verify + * that the mux is in fact present. + */ + if (i2c_smbus_read_byte(client) < 0) { + dev_warn(&client->dev, "probe failed\n"); + goto exit_free; + } + + data->type = id->driver_data; + data->last_chan = 0; /* force the first selection */ + + /* Now create an adapter for each channel */ + for (num = 0; num < chips[data->type].nchans; num++) { + force = 0; /* dynamic adap number */ + if (pdata) { + if (num < pdata->num_modes) + /* force static number */ + force = pdata->modes[num].adap_id; + else + /* discard unconfigured channels */ + break; + } + + data->virt_adaps[num] = + i2c_add_mux_adapter(adap, client, + force, num, pca954x_select_chan, + (pdata && pdata->modes[num].deselect_on_exit) + ? pca954x_deselect_mux : NULL); + + if (data->virt_adaps[num] == NULL) { + ret = -ENODEV; + dev_err(&client->dev, + "failed to register multiplexed adapter" + " %d as bus %d\n", num, force); + goto virt_reg_failed; + } + } + + dev_info(&client->dev, + "registered %d multiplexed busses for I2C %s %s\n", + num, chips[data->type].muxtype == pca954x_ismux + ? "mux" : "switch", client->name); + + return 0; + +virt_reg_failed: + for (num--; num >= 0; num--) + i2c_del_mux_adapter(data->virt_adaps[num]); +exit_free: + kfree(data); +err: + return ret; +} + +static int pca954x_remove(struct i2c_client *client) +{ + struct pca954x *data = i2c_get_clientdata(client); + const struct chip_desc *chip = &chips[data->type]; + int i, err; + + for (i = 0; i < chip->nchans; ++i) + if (data->virt_adaps[i]) { + err = i2c_del_mux_adapter(data->virt_adaps[i]); + if (err) + return err; + data->virt_adaps[i] = NULL; + } + + kfree(data); + return 0; +} + +static struct i2c_driver pca954x_driver = { + .driver = { + .name = "pca954x", + .owner = THIS_MODULE, + }, + .probe = pca954x_probe, + .remove = pca954x_remove, + .id_table = pca954x_id, +}; + +static int __init pca954x_init(void) +{ + return i2c_add_driver(&pca954x_driver); +} + +static void __exit pca954x_exit(void) +{ + i2c_del_driver(&pca954x_driver); +} + +module_init(pca954x_init); +module_exit(pca954x_exit); + +MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>"); +MODULE_DESCRIPTION("PCA954x I2C mux/switch driver"); +MODULE_LICENSE("GPL v2"); |