diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-19 04:51:10 +0400 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-19 04:51:10 +0400 |
commit | 752451f01c4567b506bf4343082682dbb8fb30dd (patch) | |
tree | ec2ec2989c93e567952ddc1ec879013aa2704f0a /drivers/i2c | |
parent | 673ab8783b596cda5b616b317b1a1b47480c66fd (diff) | |
parent | 972deb4f49b5b6703d9c6117ba0aeda2180d4447 (diff) | |
download | linux-752451f01c4567b506bf4343082682dbb8fb30dd.tar.xz |
Merge branch 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux
Pull i2c-embedded changes from Wolfram Sang:
- CBUS driver (an I2C variant)
- continued rework of the omap driver
- s3c2410 gets lots of fixes and gains pinctrl support
- at91 gains DMA support
- the GPIO muxer gains devicetree probing
- typical fixes and additions all over
* 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux: (45 commits)
i2c: omap: Remove the OMAP_I2C_FLAG_RESET_REGS_POSTIDLE flag
i2c: at91: add dma support
i2c: at91: change struct members indentation
i2c: at91: fix compilation warning
i2c: mxs: Do not disable the I2C SMBus quick mode
i2c: mxs: Handle i2c DMA failure properly
i2c: s3c2410: Remove recently introduced performance overheads
i2c: ocores: Move grlib set/get functions into #ifdef CONFIG_OF block
i2c: s3c2410: Add fix for i2c suspend/resume
i2c: s3c2410: Fix code to free gpios
i2c: i2c-cbus-gpio: introduce driver
i2c: ocores: Add support for the GRLIB port of the controller and use function pointers for getreg and setreg functions
i2c: ocores: Add irq support for sparc
i2c: omap: Move the remove constraint
ARM: dts: cfa10049: Add the i2c muxer buses to the CFA-10049
i2c: s3c2410: do not special case HDMIPHY stuck bus detection
i2c: s3c2410: use exponential back off while polling for bus idle
i2c: s3c2410: do not generate STOP for QUIRK_HDMIPHY
i2c: s3c2410: grab adapter lock while changing i2c clock
i2c: s3c2410: Add support for pinctrl
...
Diffstat (limited to 'drivers/i2c')
-rw-r--r-- | drivers/i2c/busses/Kconfig | 10 | ||||
-rw-r--r-- | drivers/i2c/busses/Makefile | 1 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-at91.c | 338 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-cbus-gpio.c | 300 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-gpio.c | 6 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-mxs.c | 2 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-nomadik.c | 14 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-ocores.c | 164 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-omap.c | 226 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-rcar.c | 6 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-s3c2410.c | 211 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-sh_mobile.c | 150 | ||||
-rw-r--r-- | drivers/i2c/muxes/i2c-mux-gpio.c | 145 |
13 files changed, 1236 insertions, 337 deletions
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index c7bff51fe524..bdca5111eb9d 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -337,6 +337,16 @@ config I2C_BLACKFIN_TWI_CLK_KHZ help The unit of the TWI clock is kHz. +config I2C_CBUS_GPIO + tristate "CBUS I2C driver" + depends on GENERIC_GPIO + help + Support for CBUS access using I2C API. Mostly relevant for Nokia + Internet Tablets (770, N800 and N810). + + This driver can also be built as a module. If so, the module + will be called i2c-cbus-gpio. + config I2C_CPM tristate "Freescale CPM1 or CPM2 (MPC8xx/826x)" depends on (CPM1 || CPM2) && OF_I2C diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index e5cb209d276c..6181f3ff263f 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -31,6 +31,7 @@ obj-$(CONFIG_I2C_POWERMAC) += i2c-powermac.o obj-$(CONFIG_I2C_AT91) += i2c-at91.o obj-$(CONFIG_I2C_AU1550) += i2c-au1550.o obj-$(CONFIG_I2C_BLACKFIN_TWI) += i2c-bfin-twi.o +obj-$(CONFIG_I2C_CBUS_GPIO) += i2c-cbus-gpio.o obj-$(CONFIG_I2C_CPM) += i2c-cpm.o obj-$(CONFIG_I2C_DAVINCI) += i2c-davinci.o obj-$(CONFIG_I2C_DESIGNWARE_CORE) += i2c-designware-core.o diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c index c02bf208084f..b4575ee4bdf3 100644 --- a/drivers/i2c/busses/i2c-at91.c +++ b/drivers/i2c/busses/i2c-at91.c @@ -19,6 +19,8 @@ #include <linux/clk.h> #include <linux/completion.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> #include <linux/err.h> #include <linux/i2c.h> #include <linux/interrupt.h> @@ -29,9 +31,11 @@ #include <linux/of_i2c.h> #include <linux/platform_device.h> #include <linux/slab.h> +#include <linux/platform_data/dma-atmel.h> #define TWI_CLK_HZ 100000 /* max 400 Kbits/s */ #define AT91_I2C_TIMEOUT msecs_to_jiffies(100) /* transfer timeout */ +#define AT91_I2C_DMA_THRESHOLD 8 /* enable DMA if transfer size is bigger than this threshold */ /* AT91 TWI register definitions */ #define AT91_TWI_CR 0x0000 /* Control Register */ @@ -66,24 +70,39 @@ #define AT91_TWI_THR 0x0034 /* Transmit Holding Register */ struct at91_twi_pdata { - unsigned clk_max_div; - unsigned clk_offset; - bool has_unre_flag; + unsigned clk_max_div; + unsigned clk_offset; + bool has_unre_flag; + bool has_dma_support; + struct at_dma_slave dma_slave; +}; + +struct at91_twi_dma { + struct dma_chan *chan_rx; + struct dma_chan *chan_tx; + struct scatterlist sg; + struct dma_async_tx_descriptor *data_desc; + enum dma_data_direction direction; + bool buf_mapped; + bool xfer_in_progress; }; struct at91_twi_dev { - struct device *dev; - void __iomem *base; - struct completion cmd_complete; - struct clk *clk; - u8 *buf; - size_t buf_len; - struct i2c_msg *msg; - int irq; - unsigned transfer_status; - struct i2c_adapter adapter; - unsigned twi_cwgr_reg; - struct at91_twi_pdata *pdata; + struct device *dev; + void __iomem *base; + struct completion cmd_complete; + struct clk *clk; + u8 *buf; + size_t buf_len; + struct i2c_msg *msg; + int irq; + unsigned imr; + unsigned transfer_status; + struct i2c_adapter adapter; + unsigned twi_cwgr_reg; + struct at91_twi_pdata *pdata; + bool use_dma; + struct at91_twi_dma dma; }; static unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg) @@ -102,6 +121,17 @@ static void at91_disable_twi_interrupts(struct at91_twi_dev *dev) AT91_TWI_TXCOMP | AT91_TWI_RXRDY | AT91_TWI_TXRDY); } +static void at91_twi_irq_save(struct at91_twi_dev *dev) +{ + dev->imr = at91_twi_read(dev, AT91_TWI_IMR) & 0x7; + at91_disable_twi_interrupts(dev); +} + +static void at91_twi_irq_restore(struct at91_twi_dev *dev) +{ + at91_twi_write(dev, AT91_TWI_IER, dev->imr); +} + static void at91_init_twi_bus(struct at91_twi_dev *dev) { at91_disable_twi_interrupts(dev); @@ -138,6 +168,28 @@ static void __devinit at91_calc_twi_clock(struct at91_twi_dev *dev, int twi_clk) dev_dbg(dev->dev, "cdiv %d ckdiv %d\n", cdiv, ckdiv); } +static void at91_twi_dma_cleanup(struct at91_twi_dev *dev) +{ + struct at91_twi_dma *dma = &dev->dma; + + at91_twi_irq_save(dev); + + if (dma->xfer_in_progress) { + if (dma->direction == DMA_FROM_DEVICE) + dmaengine_terminate_all(dma->chan_rx); + else + dmaengine_terminate_all(dma->chan_tx); + dma->xfer_in_progress = false; + } + if (dma->buf_mapped) { + dma_unmap_single(dev->dev, sg_dma_address(&dma->sg), + dev->buf_len, dma->direction); + dma->buf_mapped = false; + } + + at91_twi_irq_restore(dev); +} + static void at91_twi_write_next_byte(struct at91_twi_dev *dev) { if (dev->buf_len <= 0) @@ -154,6 +206,60 @@ static void at91_twi_write_next_byte(struct at91_twi_dev *dev) ++dev->buf; } +static void at91_twi_write_data_dma_callback(void *data) +{ + struct at91_twi_dev *dev = (struct at91_twi_dev *)data; + + dma_unmap_single(dev->dev, sg_dma_address(&dev->dma.sg), + dev->buf_len, DMA_MEM_TO_DEV); + + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_STOP); +} + +static void at91_twi_write_data_dma(struct at91_twi_dev *dev) +{ + dma_addr_t dma_addr; + struct dma_async_tx_descriptor *txdesc; + struct at91_twi_dma *dma = &dev->dma; + struct dma_chan *chan_tx = dma->chan_tx; + + if (dev->buf_len <= 0) + return; + + dma->direction = DMA_TO_DEVICE; + + at91_twi_irq_save(dev); + dma_addr = dma_map_single(dev->dev, dev->buf, dev->buf_len, + DMA_TO_DEVICE); + if (dma_mapping_error(dev->dev, dma_addr)) { + dev_err(dev->dev, "dma map failed\n"); + return; + } + dma->buf_mapped = true; + at91_twi_irq_restore(dev); + sg_dma_len(&dma->sg) = dev->buf_len; + sg_dma_address(&dma->sg) = dma_addr; + + txdesc = dmaengine_prep_slave_sg(chan_tx, &dma->sg, 1, DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!txdesc) { + dev_err(dev->dev, "dma prep slave sg failed\n"); + goto error; + } + + txdesc->callback = at91_twi_write_data_dma_callback; + txdesc->callback_param = dev; + + dma->xfer_in_progress = true; + dmaengine_submit(txdesc); + dma_async_issue_pending(chan_tx); + + return; + +error: + at91_twi_dma_cleanup(dev); +} + static void at91_twi_read_next_byte(struct at91_twi_dev *dev) { if (dev->buf_len <= 0) @@ -179,6 +285,61 @@ static void at91_twi_read_next_byte(struct at91_twi_dev *dev) ++dev->buf; } +static void at91_twi_read_data_dma_callback(void *data) +{ + struct at91_twi_dev *dev = (struct at91_twi_dev *)data; + + dma_unmap_single(dev->dev, sg_dma_address(&dev->dma.sg), + dev->buf_len, DMA_DEV_TO_MEM); + + /* The last two bytes have to be read without using dma */ + dev->buf += dev->buf_len - 2; + dev->buf_len = 2; + at91_twi_write(dev, AT91_TWI_IER, AT91_TWI_RXRDY); +} + +static void at91_twi_read_data_dma(struct at91_twi_dev *dev) +{ + dma_addr_t dma_addr; + struct dma_async_tx_descriptor *rxdesc; + struct at91_twi_dma *dma = &dev->dma; + struct dma_chan *chan_rx = dma->chan_rx; + + dma->direction = DMA_FROM_DEVICE; + + /* Keep in mind that we won't use dma to read the last two bytes */ + at91_twi_irq_save(dev); + dma_addr = dma_map_single(dev->dev, dev->buf, dev->buf_len - 2, + DMA_FROM_DEVICE); + if (dma_mapping_error(dev->dev, dma_addr)) { + dev_err(dev->dev, "dma map failed\n"); + return; + } + dma->buf_mapped = true; + at91_twi_irq_restore(dev); + dma->sg.dma_address = dma_addr; + sg_dma_len(&dma->sg) = dev->buf_len - 2; + + rxdesc = dmaengine_prep_slave_sg(chan_rx, &dma->sg, 1, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!rxdesc) { + dev_err(dev->dev, "dma prep slave sg failed\n"); + goto error; + } + + rxdesc->callback = at91_twi_read_data_dma_callback; + rxdesc->callback_param = dev; + + dma->xfer_in_progress = true; + dmaengine_submit(rxdesc); + dma_async_issue_pending(dma->chan_rx); + + return; + +error: + at91_twi_dma_cleanup(dev); +} + static irqreturn_t atmel_twi_interrupt(int irq, void *dev_id) { struct at91_twi_dev *dev = dev_id; @@ -229,12 +390,36 @@ static int at91_do_twi_transfer(struct at91_twi_dev *dev) if (dev->buf_len <= 1 && !(dev->msg->flags & I2C_M_RECV_LEN)) start_flags |= AT91_TWI_STOP; at91_twi_write(dev, AT91_TWI_CR, start_flags); - at91_twi_write(dev, AT91_TWI_IER, + /* + * When using dma, the last byte has to be read manually in + * order to not send the stop command too late and then + * to receive extra data. In practice, there are some issues + * if you use the dma to read n-1 bytes because of latency. + * Reading n-2 bytes with dma and the two last ones manually + * seems to be the best solution. + */ + if (dev->use_dma && (dev->buf_len > AT91_I2C_DMA_THRESHOLD)) { + at91_twi_read_data_dma(dev); + /* + * It is important to enable TXCOMP irq here because + * doing it only when transferring the last two bytes + * will mask NACK errors since TXCOMP is set when a + * NACK occurs. + */ + at91_twi_write(dev, AT91_TWI_IER, + AT91_TWI_TXCOMP); + } else + at91_twi_write(dev, AT91_TWI_IER, AT91_TWI_TXCOMP | AT91_TWI_RXRDY); } else { - at91_twi_write_next_byte(dev); - at91_twi_write(dev, AT91_TWI_IER, - AT91_TWI_TXCOMP | AT91_TWI_TXRDY); + if (dev->use_dma && (dev->buf_len > AT91_I2C_DMA_THRESHOLD)) { + at91_twi_write_data_dma(dev); + at91_twi_write(dev, AT91_TWI_IER, AT91_TWI_TXCOMP); + } else { + at91_twi_write_next_byte(dev); + at91_twi_write(dev, AT91_TWI_IER, + AT91_TWI_TXCOMP | AT91_TWI_TXRDY); + } } ret = wait_for_completion_interruptible_timeout(&dev->cmd_complete, @@ -242,23 +427,31 @@ static int at91_do_twi_transfer(struct at91_twi_dev *dev) if (ret == 0) { dev_err(dev->dev, "controller timed out\n"); at91_init_twi_bus(dev); - return -ETIMEDOUT; + ret = -ETIMEDOUT; + goto error; } if (dev->transfer_status & AT91_TWI_NACK) { dev_dbg(dev->dev, "received nack\n"); - return -EREMOTEIO; + ret = -EREMOTEIO; + goto error; } if (dev->transfer_status & AT91_TWI_OVRE) { dev_err(dev->dev, "overrun while reading\n"); - return -EIO; + ret = -EIO; + goto error; } if (has_unre_flag && dev->transfer_status & AT91_TWI_UNRE) { dev_err(dev->dev, "underrun while writing\n"); - return -EIO; + ret = -EIO; + goto error; } dev_dbg(dev->dev, "transfer complete\n"); return 0; + +error: + at91_twi_dma_cleanup(dev); + return ret; } static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num) @@ -329,36 +522,42 @@ static struct at91_twi_pdata at91rm9200_config = { .clk_max_div = 5, .clk_offset = 3, .has_unre_flag = true, + .has_dma_support = false, }; static struct at91_twi_pdata at91sam9261_config = { .clk_max_div = 5, .clk_offset = 4, .has_unre_flag = false, + .has_dma_support = false, }; static struct at91_twi_pdata at91sam9260_config = { .clk_max_div = 7, .clk_offset = 4, .has_unre_flag = false, + .has_dma_support = false, }; static struct at91_twi_pdata at91sam9g20_config = { .clk_max_div = 7, .clk_offset = 4, .has_unre_flag = false, + .has_dma_support = false, }; static struct at91_twi_pdata at91sam9g10_config = { .clk_max_div = 7, .clk_offset = 4, .has_unre_flag = false, + .has_dma_support = false, }; static struct at91_twi_pdata at91sam9x5_config = { .clk_max_div = 7, .clk_offset = 4, .has_unre_flag = false, + .has_dma_support = true, }; static const struct platform_device_id at91_twi_devtypes[] = { @@ -405,6 +604,90 @@ MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids); #define atmel_twi_dt_ids NULL #endif +static bool __devinit filter(struct dma_chan *chan, void *slave) +{ + struct at_dma_slave *sl = slave; + + if (sl->dma_dev == chan->device->dev) { + chan->private = sl; + return true; + } else { + return false; + } +} + +static int __devinit at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr) +{ + int ret = 0; + struct at_dma_slave *sdata; + struct dma_slave_config slave_config; + struct at91_twi_dma *dma = &dev->dma; + + sdata = &dev->pdata->dma_slave; + + memset(&slave_config, 0, sizeof(slave_config)); + slave_config.src_addr = (dma_addr_t)phy_addr + AT91_TWI_RHR; + slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + slave_config.src_maxburst = 1; + slave_config.dst_addr = (dma_addr_t)phy_addr + AT91_TWI_THR; + slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + slave_config.dst_maxburst = 1; + slave_config.device_fc = false; + + if (sdata && sdata->dma_dev) { + dma_cap_mask_t mask; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + dma->chan_tx = dma_request_channel(mask, filter, sdata); + if (!dma->chan_tx) { + dev_err(dev->dev, "no DMA channel available for tx\n"); + ret = -EBUSY; + goto error; + } + dma->chan_rx = dma_request_channel(mask, filter, sdata); + if (!dma->chan_rx) { + dev_err(dev->dev, "no DMA channel available for rx\n"); + ret = -EBUSY; + goto error; + } + } else { + ret = -EINVAL; + goto error; + } + + slave_config.direction = DMA_MEM_TO_DEV; + if (dmaengine_slave_config(dma->chan_tx, &slave_config)) { + dev_err(dev->dev, "failed to configure tx channel\n"); + ret = -EINVAL; + goto error; + } + + slave_config.direction = DMA_DEV_TO_MEM; + if (dmaengine_slave_config(dma->chan_rx, &slave_config)) { + dev_err(dev->dev, "failed to configure rx channel\n"); + ret = -EINVAL; + goto error; + } + + sg_init_table(&dma->sg, 1); + dma->buf_mapped = false; + dma->xfer_in_progress = false; + + dev_info(dev->dev, "using %s (tx) and %s (rx) for DMA transfers\n", + dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx)); + + return ret; + +error: + dev_info(dev->dev, "can't use DMA\n"); + if (dma->chan_rx) + dma_release_channel(dma->chan_rx); + if (dma->chan_tx) + dma_release_channel(dma->chan_tx); + return ret; +} + static struct at91_twi_pdata * __devinit at91_twi_get_driver_data( struct platform_device *pdev) { @@ -413,7 +696,7 @@ static struct at91_twi_pdata * __devinit at91_twi_get_driver_data( match = of_match_node(atmel_twi_dt_ids, pdev->dev.of_node); if (!match) return NULL; - return match->data; + return (struct at91_twi_pdata *)match->data; } return (struct at91_twi_pdata *) platform_get_device_id(pdev)->driver_data; } @@ -423,6 +706,7 @@ static int __devinit at91_twi_probe(struct platform_device *pdev) struct at91_twi_dev *dev; struct resource *mem; int rc; + u32 phy_addr; dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL); if (!dev) @@ -433,6 +717,7 @@ static int __devinit at91_twi_probe(struct platform_device *pdev) mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!mem) return -ENODEV; + phy_addr = mem->start; dev->pdata = at91_twi_get_driver_data(pdev); if (!dev->pdata) @@ -462,6 +747,11 @@ static int __devinit at91_twi_probe(struct platform_device *pdev) } clk_prepare_enable(dev->clk); + if (dev->pdata->has_dma_support) { + if (at91_twi_configure_dma(dev, phy_addr) == 0) + dev->use_dma = true; + } + at91_calc_twi_clock(dev, TWI_CLK_HZ); at91_init_twi_bus(dev); diff --git a/drivers/i2c/busses/i2c-cbus-gpio.c b/drivers/i2c/busses/i2c-cbus-gpio.c new file mode 100644 index 000000000000..98386d659318 --- /dev/null +++ b/drivers/i2c/busses/i2c-cbus-gpio.c @@ -0,0 +1,300 @@ +/* + * CBUS I2C driver for Nokia Internet Tablets. + * + * Copyright (C) 2004-2010 Nokia Corporation + * + * Based on code written by Juha Yrjölä, David Weinehall, Mikko Ylinen and + * Felipe Balbi. Converted to I2C driver by Aaro Koskinen. + * + * This file is subject to the terms and conditions of the GNU General + * Public License. See the file "COPYING" in the main directory of this + * archive for more details. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/io.h> +#include <linux/i2c.h> +#include <linux/gpio.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_gpio.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/platform_data/i2c-cbus-gpio.h> + +/* + * Bit counts are derived from Nokia implementation. These should be checked + * if other CBUS implementations appear. + */ +#define CBUS_ADDR_BITS 3 +#define CBUS_REG_BITS 5 + +struct cbus_host { + spinlock_t lock; /* host lock */ + struct device *dev; + int clk_gpio; + int dat_gpio; + int sel_gpio; +}; + +/** + * cbus_send_bit - sends one bit over the bus + * @host: the host we're using + * @bit: one bit of information to send + */ +static void cbus_send_bit(struct cbus_host *host, unsigned bit) +{ + gpio_set_value(host->dat_gpio, bit ? 1 : 0); + gpio_set_value(host->clk_gpio, 1); + gpio_set_value(host->clk_gpio, 0); +} + +/** + * cbus_send_data - sends @len amount of data over the bus + * @host: the host we're using + * @data: the data to send + * @len: size of the transfer + */ +static void cbus_send_data(struct cbus_host *host, unsigned data, unsigned len) +{ + int i; + + for (i = len; i > 0; i--) + cbus_send_bit(host, data & (1 << (i - 1))); +} + +/** + * cbus_receive_bit - receives one bit from the bus + * @host: the host we're using + */ +static int cbus_receive_bit(struct cbus_host *host) +{ + int ret; + + gpio_set_value(host->clk_gpio, 1); + ret = gpio_get_value(host->dat_gpio); + gpio_set_value(host->clk_gpio, 0); + return ret; +} + +/** + * cbus_receive_word - receives 16-bit word from the bus + * @host: the host we're using + */ +static int cbus_receive_word(struct cbus_host *host) +{ + int ret = 0; + int i; + + for (i = 16; i > 0; i--) { + int bit = cbus_receive_bit(host); + + if (bit < 0) + return bit; + + if (bit) + ret |= 1 << (i - 1); + } + return ret; +} + +/** + * cbus_transfer - transfers data over the bus + * @host: the host we're using + * @rw: read/write flag + * @dev: device address + * @reg: register address + * @data: if @rw == I2C_SBUS_WRITE data to send otherwise 0 + */ +static int cbus_transfer(struct cbus_host *host, char rw, unsigned dev, + unsigned reg, unsigned data) +{ + unsigned long flags; + int ret; + + /* We don't want interrupts disturbing our transfer */ + spin_lock_irqsave(&host->lock, flags); + + /* Reset state and start of transfer, SEL stays down during transfer */ + gpio_set_value(host->sel_gpio, 0); + + /* Set the DAT pin to output */ + gpio_direction_output(host->dat_gpio, 1); + + /* Send the device address */ + cbus_send_data(host, dev, CBUS_ADDR_BITS); + + /* Send the rw flag */ + cbus_send_bit(host, rw == I2C_SMBUS_READ); + + /* Send the register address */ + cbus_send_data(host, reg, CBUS_REG_BITS); + + if (rw == I2C_SMBUS_WRITE) { + cbus_send_data(host, data, 16); + ret = 0; + } else { + ret = gpio_direction_input(host->dat_gpio); + if (ret) { + dev_dbg(host->dev, "failed setting direction\n"); + goto out; + } + gpio_set_value(host->clk_gpio, 1); + + ret = cbus_receive_word(host); + if (ret < 0) { + dev_dbg(host->dev, "failed receiving data\n"); + goto out; + } + } + + /* Indicate end of transfer, SEL goes up until next transfer */ + gpio_set_value(host->sel_gpio, 1); + gpio_set_value(host->clk_gpio, 1); + gpio_set_value(host->clk_gpio, 0); + +out: + spin_unlock_irqrestore(&host->lock, flags); + + return ret; +} + +static int cbus_i2c_smbus_xfer(struct i2c_adapter *adapter, + u16 addr, + unsigned short flags, + char read_write, + u8 command, + int size, + union i2c_smbus_data *data) +{ + struct cbus_host *chost = i2c_get_adapdata(adapter); + int ret; + + if (size != I2C_SMBUS_WORD_DATA) + return -EINVAL; + + ret = cbus_transfer(chost, read_write == I2C_SMBUS_READ, addr, + command, data->word); + if (ret < 0) + return ret; + + if (read_write == I2C_SMBUS_READ) + data->word = ret; + + return 0; +} + +static u32 cbus_i2c_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_READ_WORD_DATA | I2C_FUNC_SMBUS_WRITE_WORD_DATA; +} + +static const struct i2c_algorithm cbus_i2c_algo = { + .smbus_xfer = cbus_i2c_smbus_xfer, + .functionality = cbus_i2c_func, +}; + +static int cbus_i2c_remove(struct platform_device *pdev) +{ + struct i2c_adapter *adapter = platform_get_drvdata(pdev); + + return i2c_del_adapter(adapter); +} + +static int cbus_i2c_probe(struct platform_device *pdev) +{ + struct i2c_adapter *adapter; + struct cbus_host *chost; + int ret; + + adapter = devm_kzalloc(&pdev->dev, sizeof(struct i2c_adapter), + GFP_KERNEL); + if (!adapter) + return -ENOMEM; + + chost = devm_kzalloc(&pdev->dev, sizeof(*chost), GFP_KERNEL); + if (!chost) + return -ENOMEM; + + if (pdev->dev.of_node) { + struct device_node *dnode = pdev->dev.of_node; + if (of_gpio_count(dnode) != 3) + return -ENODEV; + chost->clk_gpio = of_get_gpio(dnode, 0); + chost->dat_gpio = of_get_gpio(dnode, 1); + chost->sel_gpio = of_get_gpio(dnode, 2); + } else if (pdev->dev.platform_data) { + struct i2c_cbus_platform_data *pdata = pdev->dev.platform_data; + chost->clk_gpio = pdata->clk_gpio; + chost->dat_gpio = pdata->dat_gpio; + chost->sel_gpio = pdata->sel_gpio; + } else { + return -ENODEV; + } + + adapter->owner = THIS_MODULE; + adapter->class = I2C_CLASS_HWMON; + adapter->dev.parent = &pdev->dev; + adapter->nr = pdev->id; + adapter->timeout = HZ; + adapter->algo = &cbus_i2c_algo; + strlcpy(adapter->name, "CBUS I2C adapter", sizeof(adapter->name)); + + spin_lock_init(&chost->lock); + chost->dev = &pdev->dev; + + ret = devm_gpio_request_one(&pdev->dev, chost->clk_gpio, + GPIOF_OUT_INIT_LOW, "CBUS clk"); + if (ret) + return ret; + + ret = devm_gpio_request_one(&pdev->dev, chost->dat_gpio, GPIOF_IN, + "CBUS data"); + if (ret) + return ret; + + ret = devm_gpio_request_one(&pdev->dev, chost->sel_gpio, + GPIOF_OUT_INIT_HIGH, "CBUS sel"); + if (ret) + return ret; + + i2c_set_adapdata(adapter, chost); + platform_set_drvdata(pdev, adapter); + + return i2c_add_numbered_adapter(adapter); +} + +#if defined(CONFIG_OF) +static const struct of_device_id i2c_cbus_dt_ids[] = { + { .compatible = "i2c-cbus-gpio", }, + { } +}; +MODULE_DEVICE_TABLE(of, i2c_cbus_dt_ids); +#endif + +static struct platform_driver cbus_i2c_driver = { + .probe = cbus_i2c_probe, + .remove = cbus_i2c_remove, + .driver = { + .owner = THIS_MODULE, + .name = "i2c-cbus-gpio", + }, +}; +module_platform_driver(cbus_i2c_driver); + +MODULE_ALIAS("platform:i2c-cbus-gpio"); +MODULE_DESCRIPTION("CBUS I2C driver"); +MODULE_AUTHOR("Juha Yrjölä"); +MODULE_AUTHOR("David Weinehall"); +MODULE_AUTHOR("Mikko Ylinen"); +MODULE_AUTHOR("Felipe Balbi"); +MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-gpio.c b/drivers/i2c/busses/i2c-gpio.c index e62d2d938628..257299a92df3 100644 --- a/drivers/i2c/busses/i2c-gpio.c +++ b/drivers/i2c/busses/i2c-gpio.c @@ -184,7 +184,11 @@ static int __devinit i2c_gpio_probe(struct platform_device *pdev) bit_data->data = pdata; adap->owner = THIS_MODULE; - snprintf(adap->name, sizeof(adap->name), "i2c-gpio%d", pdev->id); + if (pdev->dev.of_node) + strlcpy(adap->name, dev_name(&pdev->dev), sizeof(adap->name)); + else + snprintf(adap->name, sizeof(adap->name), "i2c-gpio%d", pdev->id); + adap->algo_data = bit_data; adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD; adap->dev.parent = &pdev->dev; diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c index 0670da79ee5e..6ed53da9e1f4 100644 --- a/drivers/i2c/busses/i2c-mxs.c +++ b/drivers/i2c/busses/i2c-mxs.c @@ -359,7 +359,7 @@ static int mxs_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], static u32 mxs_i2c_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 irqreturn_t mxs_i2c_isr(int this_irq, void *dev_id) diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c index 02c3115a2dfa..8b2ffcf45322 100644 --- a/drivers/i2c/busses/i2c-nomadik.c +++ b/drivers/i2c/busses/i2c-nomadik.c @@ -435,13 +435,6 @@ static int read_i2c(struct nmk_i2c_dev *dev, u16 flags) timeout = wait_for_completion_timeout( &dev->xfer_complete, dev->adap.timeout); - if (timeout < 0) { - dev_err(&dev->adev->dev, - "wait_for_completion_timeout " - "returned %d waiting for event\n", timeout); - status = timeout; - } - if (timeout == 0) { /* Controller timed out */ dev_err(&dev->adev->dev, "read from slave 0x%x timed out\n", @@ -523,13 +516,6 @@ static int write_i2c(struct nmk_i2c_dev *dev, u16 flags) timeout = wait_for_completion_timeout( &dev->xfer_complete, dev->adap.timeout); - if (timeout < 0) { - dev_err(&dev->adev->dev, - "wait_for_completion_timeout " - "returned %d waiting for event\n", timeout); - status = timeout; - } - if (timeout == 0) { /* Controller timed out */ dev_err(&dev->adev->dev, "write to slave 0x%x timed out\n", diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c index 15da1ac7cf9e..9b35c9fbb2fe 100644 --- a/drivers/i2c/busses/i2c-ocores.c +++ b/drivers/i2c/busses/i2c-ocores.c @@ -4,6 +4,9 @@ * * Peter Korsgaard <jacmet@sunsite.dk> * + * Support for the GRLIB port of the controller by + * Andreas Larsson <andreas@gaisler.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. @@ -34,6 +37,8 @@ struct ocores_i2c { int nmsgs; int state; /* see STATE_ */ int clock_khz; + void (*setreg)(struct ocores_i2c *i2c, int reg, u8 value); + u8 (*getreg)(struct ocores_i2c *i2c, int reg); }; /* registers */ @@ -67,24 +72,47 @@ struct ocores_i2c { #define STATE_READ 3 #define STATE_ERROR 4 +#define TYPE_OCORES 0 +#define TYPE_GRLIB 1 + +static void oc_setreg_8(struct ocores_i2c *i2c, int reg, u8 value) +{ + iowrite8(value, i2c->base + (reg << i2c->reg_shift)); +} + +static void oc_setreg_16(struct ocores_i2c *i2c, int reg, u8 value) +{ + iowrite16(value, i2c->base + (reg << i2c->reg_shift)); +} + +static void oc_setreg_32(struct ocores_i2c *i2c, int reg, u8 value) +{ + iowrite32(value, i2c->base + (reg << i2c->reg_shift)); +} + +static inline u8 oc_getreg_8(struct ocores_i2c *i2c, int reg) +{ + return ioread8(i2c->base + (reg << i2c->reg_shift)); +} + +static inline u8 oc_getreg_16(struct ocores_i2c *i2c, int reg) +{ + return ioread16(i2c->base + (reg << i2c->reg_shift)); +} + +static inline u8 oc_getreg_32(struct ocores_i2c *i2c, int reg) +{ + return ioread32(i2c->base + (reg << i2c->reg_shift)); +} + static inline void oc_setreg(struct ocores_i2c *i2c, int reg, u8 value) { - if (i2c->reg_io_width == 4) - iowrite32(value, i2c->base + (reg << i2c->reg_shift)); - else if (i2c->reg_io_width == 2) - iowrite16(value, i2c->base + (reg << i2c->reg_shift)); - else - iowrite8(value, i2c->base + (reg << i2c->reg_shift)); + i2c->setreg(i2c, reg, value); } static inline u8 oc_getreg(struct ocores_i2c *i2c, int reg) { - if (i2c->reg_io_width == 4) - return ioread32(i2c->base + (reg << i2c->reg_shift)); - else if (i2c->reg_io_width == 2) - return ioread16(i2c->base + (reg << i2c->reg_shift)); - else - return ioread8(i2c->base + (reg << i2c->reg_shift)); + return i2c->getreg(i2c, reg); } static void ocores_process(struct ocores_i2c *i2c) @@ -223,11 +251,59 @@ static struct i2c_adapter ocores_adapter = { .algo = &ocores_algorithm, }; +static struct of_device_id ocores_i2c_match[] = { + { + .compatible = "opencores,i2c-ocores", + .data = (void *)TYPE_OCORES, + }, + { + .compatible = "aeroflexgaisler,i2cmst", + .data = (void *)TYPE_GRLIB, + }, + {}, +}; +MODULE_DEVICE_TABLE(of, ocores_i2c_match); + #ifdef CONFIG_OF +/* Read and write functions for the GRLIB port of the controller. Registers are + * 32-bit big endian and the PRELOW and PREHIGH registers are merged into one + * register. The subsequent registers has their offset decreased accordingly. */ +static u8 oc_getreg_grlib(struct ocores_i2c *i2c, int reg) +{ + u32 rd; + int rreg = reg; + if (reg != OCI2C_PRELOW) + rreg--; + rd = ioread32be(i2c->base + (rreg << i2c->reg_shift)); + if (reg == OCI2C_PREHIGH) + return (u8)(rd >> 8); + else + return (u8)rd; +} + +static void oc_setreg_grlib(struct ocores_i2c *i2c, int reg, u8 value) +{ + u32 curr, wr; + int rreg = reg; + if (reg != OCI2C_PRELOW) + rreg--; + if (reg == OCI2C_PRELOW || reg == OCI2C_PREHIGH) { + curr = ioread32be(i2c->base + (rreg << i2c->reg_shift)); + if (reg == OCI2C_PRELOW) + wr = (curr & 0xff00) | value; + else + wr = (((u32)value) << 8) | (curr & 0xff); + } else { + wr = value; + } + iowrite32be(wr, i2c->base + (rreg << i2c->reg_shift)); +} + static int ocores_i2c_of_probe(struct platform_device *pdev, struct ocores_i2c *i2c) { struct device_node *np = pdev->dev.of_node; + const struct of_device_id *match; u32 val; if (of_property_read_u32(np, "reg-shift", &i2c->reg_shift)) { @@ -253,6 +329,14 @@ static int ocores_i2c_of_probe(struct platform_device *pdev, of_property_read_u32(pdev->dev.of_node, "reg-io-width", &i2c->reg_io_width); + + match = of_match_node(ocores_i2c_match, pdev->dev.of_node); + if (match && (int)match->data == TYPE_GRLIB) { + dev_dbg(&pdev->dev, "GRLIB variant of i2c-ocores\n"); + i2c->setreg = oc_setreg_grlib; + i2c->getreg = oc_getreg_grlib; + } + return 0; } #else @@ -263,7 +347,8 @@ static int __devinit ocores_i2c_probe(struct platform_device *pdev) { struct ocores_i2c *i2c; struct ocores_i2c_platform_data *pdata; - struct resource *res, *res2; + struct resource *res; + int irq; int ret; int i; @@ -271,26 +356,17 @@ static int __devinit ocores_i2c_probe(struct platform_device *pdev) if (!res) return -ENODEV; - res2 = platform_get_resource(pdev, IORESOURCE_IRQ, 0); - if (!res2) - return -ENODEV; + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); if (!i2c) return -ENOMEM; - if (!devm_request_mem_region(&pdev->dev, res->start, - resource_size(res), pdev->name)) { - dev_err(&pdev->dev, "Memory region busy\n"); - return -EBUSY; - } - - i2c->base = devm_ioremap_nocache(&pdev->dev, res->start, - resource_size(res)); - if (!i2c->base) { - dev_err(&pdev->dev, "Unable to map registers\n"); - return -EIO; - } + i2c->base = devm_request_and_ioremap(&pdev->dev, res); + if (!i2c->base) + return -EADDRNOTAVAIL; pdata = pdev->dev.platform_data; if (pdata) { @@ -306,10 +382,34 @@ static int __devinit ocores_i2c_probe(struct platform_device *pdev) if (i2c->reg_io_width == 0) i2c->reg_io_width = 1; /* Set to default value */ + if (!i2c->setreg || !i2c->getreg) { + switch (i2c->reg_io_width) { + case 1: + i2c->setreg = oc_setreg_8; + i2c->getreg = oc_getreg_8; + break; + + case 2: + i2c->setreg = oc_setreg_16; + i2c->getreg = oc_getreg_16; + break; + + case 4: + i2c->setreg = oc_setreg_32; + i2c->getreg = oc_getreg_32; + break; + + default: + dev_err(&pdev->dev, "Unsupported I/O width (%d)\n", + i2c->reg_io_width); + return -EINVAL; + } + } + ocores_init(i2c); init_waitqueue_head(&i2c->wait); - ret = devm_request_irq(&pdev->dev, res2->start, ocores_isr, 0, + ret = devm_request_irq(&pdev->dev, irq, ocores_isr, 0, pdev->name, i2c); if (ret) { dev_err(&pdev->dev, "Cannot claim IRQ\n"); @@ -383,12 +483,6 @@ static SIMPLE_DEV_PM_OPS(ocores_i2c_pm, ocores_i2c_suspend, ocores_i2c_resume); #define OCORES_I2C_PM NULL #endif -static struct of_device_id ocores_i2c_match[] = { - { .compatible = "opencores,i2c-ocores", }, - {}, -}; -MODULE_DEVICE_TABLE(of, ocores_i2c_match); - static struct platform_driver ocores_i2c_driver = { .probe = ocores_i2c_probe, .remove = __devexit_p(ocores_i2c_remove), diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index 3525c9e62cb0..7a62acb7d262 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -43,14 +43,16 @@ #include <linux/slab.h> #include <linux/i2c-omap.h> #include <linux/pm_runtime.h> +#include <linux/pinctrl/consumer.h> /* I2C controller revisions */ #define OMAP_I2C_OMAP1_REV_2 0x20 /* I2C controller revisions present on specific hardware */ -#define OMAP_I2C_REV_ON_2430 0x36 -#define OMAP_I2C_REV_ON_3430_3530 0x3C -#define OMAP_I2C_REV_ON_3630_4430 0x40 +#define OMAP_I2C_REV_ON_2430 0x00000036 +#define OMAP_I2C_REV_ON_3430_3530 0x0000003C +#define OMAP_I2C_REV_ON_3630 0x00000040 +#define OMAP_I2C_REV_ON_4430_PLUS 0x50400002 /* timeout waiting for the controller to respond */ #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000)) @@ -190,7 +192,6 @@ struct omap_i2c_dev { void (*set_mpu_wkup_lat)(struct device *dev, long latency); u32 speed; /* Speed of bus in kHz */ - u32 dtrev; /* extra revision from DT */ u32 flags; u16 cmd_err; u8 *buf; @@ -202,17 +203,18 @@ struct omap_i2c_dev { * fifo_size==0 implies no fifo * if set, should be trsh+1 */ - u8 rev; + u32 rev; unsigned b_hw:1; /* bad h/w fixes */ unsigned receiver:1; /* true when we're in receiver mode */ u16 iestate; /* Saved interrupt register */ u16 pscstate; u16 scllstate; u16 sclhstate; - u16 bufstate; u16 syscstate; u16 westate; u16 errata; + + struct pinctrl *pins; }; static const u8 reg_map_ip_v1[] = { @@ -275,16 +277,39 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg) (i2c_dev->regs[reg] << i2c_dev->reg_shift)); } -static int omap_i2c_init(struct omap_i2c_dev *dev) +static void __omap_i2c_init(struct omap_i2c_dev *dev) +{ + + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); + + /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */ + omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate); + + /* SCL low and high time values */ + omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate); + omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate); + if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) + omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate); + + /* Take the I2C module out of reset: */ + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); + + /* + * Don't write to this register if the IE state is 0 as it can + * cause deadlock. + */ + if (dev->iestate) + omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate); +} + +static int omap_i2c_reset(struct omap_i2c_dev *dev) { - u16 psc = 0, scll = 0, sclh = 0, buf = 0; - u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0; - unsigned long fclk_rate = 12000000; unsigned long timeout; - unsigned long internal_clk = 0; - struct clk *fclk; + u16 sysc; if (dev->rev >= OMAP_I2C_OMAP1_REV_2) { + sysc = omap_i2c_read_reg(dev, OMAP_I2C_SYSC_REG); + /* Disable I2C controller before soft reset */ omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) & @@ -306,32 +331,28 @@ static int omap_i2c_init(struct omap_i2c_dev *dev) } /* SYSC register is cleared by the reset; rewrite it */ - if (dev->rev == OMAP_I2C_REV_ON_2430) { - - omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, - SYSC_AUTOIDLE_MASK); - - } else if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) { - dev->syscstate = SYSC_AUTOIDLE_MASK; - dev->syscstate |= SYSC_ENAWAKEUP_MASK; - dev->syscstate |= (SYSC_IDLEMODE_SMART << - __ffs(SYSC_SIDLEMODE_MASK)); - dev->syscstate |= (SYSC_CLOCKACTIVITY_FCLK << - __ffs(SYSC_CLOCKACTIVITY_MASK)); - - omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, - dev->syscstate); - /* - * Enabling all wakup sources to stop I2C freezing on - * WFI instruction. - * REVISIT: Some wkup sources might not be needed. - */ - dev->westate = OMAP_I2C_WE_ALL; - omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, - dev->westate); - } + omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, sysc); + + } + return 0; +} + +static int omap_i2c_init(struct omap_i2c_dev *dev) +{ + u16 psc = 0, scll = 0, sclh = 0; + u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0; + unsigned long fclk_rate = 12000000; + unsigned long internal_clk = 0; + struct clk *fclk; + + if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) { + /* + * Enabling all wakup sources to stop I2C freezing on + * WFI instruction. + * REVISIT: Some wkup sources might not be needed. + */ + dev->westate = OMAP_I2C_WE_ALL; } - omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) { /* @@ -416,28 +437,17 @@ static int omap_i2c_init(struct omap_i2c_dev *dev) sclh = fclk_rate / (dev->speed * 2) - 7 + psc; } - /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */ - omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc); - - /* SCL low and high time values */ - omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll); - omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh); - - /* Take the I2C module out of reset: */ - omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); - - /* Enable interrupts */ dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY | OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK | OMAP_I2C_IE_AL) | ((dev->fifo_size) ? (OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0); - omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate); - if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) { - dev->pscstate = psc; - dev->scllstate = scll; - dev->sclhstate = sclh; - dev->bufstate = buf; - } + + dev->pscstate = psc; + dev->scllstate = scll; + dev->sclhstate = sclh; + + __omap_i2c_init(dev); + return 0; } @@ -490,7 +500,7 @@ static void omap_i2c_resize_fifo(struct omap_i2c_dev *dev, u8 size, bool is_rx) omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf); - if (dev->rev < OMAP_I2C_REV_ON_3630_4430) + if (dev->rev < OMAP_I2C_REV_ON_3630) dev->b_hw = 1; /* Enable hardware fixes */ /* calculate wakeup latency constraint for MPU */ @@ -586,7 +596,8 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap, OMAP_I2C_TIMEOUT); if (timeout == 0) { dev_err(dev->dev, "controller timed out\n"); - omap_i2c_init(dev); + omap_i2c_reset(dev); + __omap_i2c_init(dev); return -ETIMEDOUT; } @@ -596,7 +607,8 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap, /* We have an error */ if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR | OMAP_I2C_STAT_XUDF)) { - omap_i2c_init(dev); + omap_i2c_reset(dev); + __omap_i2c_init(dev); return -EIO; } @@ -642,13 +654,14 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) break; } - if (dev->set_mpu_wkup_lat != NULL) - dev->set_mpu_wkup_lat(dev->dev, -1); - if (r == 0) r = num; omap_i2c_wait_for_bb(dev); + + if (dev->set_mpu_wkup_lat != NULL) + dev->set_mpu_wkup_lat(dev->dev, -1); + out: pm_runtime_mark_last_busy(dev->dev); pm_runtime_put_autosuspend(dev->dev); @@ -1025,9 +1038,7 @@ static const struct i2c_algorithm omap_i2c_algo = { #ifdef CONFIG_OF static struct omap_i2c_bus_platform_data omap3_pdata = { .rev = OMAP_I2C_IP_VERSION_1, - .flags = OMAP_I2C_FLAG_APPLY_ERRATA_I207 | - OMAP_I2C_FLAG_RESET_REGS_POSTIDLE | - OMAP_I2C_FLAG_BUS_SHIFT_2, + .flags = OMAP_I2C_FLAG_BUS_SHIFT_2, }; static struct omap_i2c_bus_platform_data omap4_pdata = { @@ -1048,6 +1059,16 @@ static const struct of_device_id omap_i2c_of_match[] = { MODULE_DEVICE_TABLE(of, omap_i2c_of_match); #endif +#define OMAP_I2C_SCHEME(rev) ((rev & 0xc000) >> 14) + +#define OMAP_I2C_REV_SCHEME_0_MAJOR(rev) (rev >> 4) +#define OMAP_I2C_REV_SCHEME_0_MINOR(rev) (rev & 0xf) + +#define OMAP_I2C_REV_SCHEME_1_MAJOR(rev) ((rev & 0x0700) >> 7) +#define OMAP_I2C_REV_SCHEME_1_MINOR(rev) (rev & 0x1f) +#define OMAP_I2C_SCHEME_0 0 +#define OMAP_I2C_SCHEME_1 1 + static int __devinit omap_i2c_probe(struct platform_device *pdev) { @@ -1060,6 +1081,8 @@ omap_i2c_probe(struct platform_device *pdev) const struct of_device_id *match; int irq; int r; + u32 rev; + u16 minor, major, scheme; /* NOTE: driver uses the static register mapping */ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); @@ -1091,7 +1114,6 @@ omap_i2c_probe(struct platform_device *pdev) u32 freq = 100000; /* default to 100000 Hz */ pdata = match->data; - dev->dtrev = pdata->rev; dev->flags = pdata->flags; of_property_read_u32(node, "clock-frequency", &freq); @@ -1101,7 +1123,16 @@ omap_i2c_probe(struct platform_device *pdev) dev->speed = pdata->clkrate; dev->flags = pdata->flags; dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat; - dev->dtrev = pdata->rev; + } + + dev->pins = devm_pinctrl_get_select_default(&pdev->dev); + if (IS_ERR(dev->pins)) { + if (PTR_ERR(dev->pins) == -EPROBE_DEFER) + return -EPROBE_DEFER; + + dev_warn(&pdev->dev, "did not get pins for i2c error: %li\n", + PTR_ERR(dev->pins)); + dev->pins = NULL; } dev->dev = &pdev->dev; @@ -1114,11 +1145,6 @@ omap_i2c_probe(struct platform_device *pdev) dev->reg_shift = (dev->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3; - if (dev->dtrev == OMAP_I2C_IP_VERSION_2) - dev->regs = (u8 *)reg_map_ip_v2; - else - dev->regs = (u8 *)reg_map_ip_v1; - pm_runtime_enable(dev->dev); pm_runtime_set_autosuspend_delay(dev->dev, OMAP_I2C_PM_TIMEOUT); pm_runtime_use_autosuspend(dev->dev); @@ -1127,11 +1153,37 @@ omap_i2c_probe(struct platform_device *pdev) if (IS_ERR_VALUE(r)) goto err_free_mem; - dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff; + /* + * Read the Rev hi bit-[15:14] ie scheme this is 1 indicates ver2. + * On omap1/3/2 Offset 4 is IE Reg the bit [15:14] is 0 at reset. + * Also since the omap_i2c_read_reg uses reg_map_ip_* a + * raw_readw is done. + */ + rev = __raw_readw(dev->base + 0x04); + + scheme = OMAP_I2C_SCHEME(rev); + switch (scheme) { + case OMAP_I2C_SCHEME_0: + dev->regs = (u8 *)reg_map_ip_v1; + dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG); + minor = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev); + major = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev); + break; + case OMAP_I2C_SCHEME_1: + /* FALLTHROUGH */ + default: + dev->regs = (u8 *)reg_map_ip_v2; + rev = (rev << 16) | + omap_i2c_read_reg(dev, OMAP_I2C_IP_V2_REVNB_LO); + minor = OMAP_I2C_REV_SCHEME_1_MINOR(rev); + major = OMAP_I2C_REV_SCHEME_1_MAJOR(rev); + dev->rev = rev; + } dev->errata = 0; - if (dev->flags & OMAP_I2C_FLAG_APPLY_ERRATA_I207) + if (dev->rev >= OMAP_I2C_REV_ON_2430 && + dev->rev < OMAP_I2C_REV_ON_4430_PLUS) dev->errata |= I2C_OMAP_ERRATA_I207; if (dev->rev <= OMAP_I2C_REV_ON_3430_3530) @@ -1152,7 +1204,7 @@ omap_i2c_probe(struct platform_device *pdev) dev->fifo_size = (dev->fifo_size / 2); - if (dev->rev < OMAP_I2C_REV_ON_3630_4430) + if (dev->rev < OMAP_I2C_REV_ON_3630) dev->b_hw = 1; /* Enable hardware fixes */ /* calculate wakeup latency constraint for MPU */ @@ -1195,8 +1247,8 @@ omap_i2c_probe(struct platform_device *pdev) goto err_unuse_clocks; } - dev_info(dev->dev, "bus %d rev%d.%d.%d at %d kHz\n", adap->nr, - dev->dtrev, dev->rev >> 4, dev->rev & 0xf, dev->speed); + dev_info(dev->dev, "bus %d rev%d.%d at %d kHz\n", adap->nr, + major, minor, dev->speed); of_i2c_register_devices(adap); @@ -1239,14 +1291,13 @@ static int omap_i2c_runtime_suspend(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct omap_i2c_dev *_dev = platform_get_drvdata(pdev); - u16 iv; _dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG); omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0); if (_dev->rev < OMAP_I2C_OMAP1_REV_2) { - iv = omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */ + omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */ } else { omap_i2c_write_reg(_dev, OMAP_I2C_STAT_REG, _dev->iestate); @@ -1262,23 +1313,10 @@ static int omap_i2c_runtime_resume(struct device *dev) struct platform_device *pdev = to_platform_device(dev); struct omap_i2c_dev *_dev = platform_get_drvdata(pdev); - if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) { - omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0); - omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate); - omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate); - omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate); - omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate); - omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate); - omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate); - omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); - } + if (!_dev->regs) + return 0; - /* - * Don't write to this register if the IE state is 0 as it can - * cause deadlock. - */ - if (_dev->iestate) - omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate); + __omap_i2c_init(_dev); return 0; } diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index f9399d163af2..72a8071a5556 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -642,7 +642,7 @@ static int __devinit rcar_i2c_probe(struct platform_device *pdev) if (ret < 0) return ret; - priv->io = devm_ioremap(dev, res->start, resource_size(res)); + priv->io = devm_request_and_ioremap(dev, res); if (!priv->io) { dev_err(dev, "cannot ioremap\n"); return -ENODEV; @@ -693,7 +693,7 @@ static int __devexit rcar_i2c_remove(struct platform_device *pdev) return 0; } -static struct platform_driver rcar_i2c_drv = { +static struct platform_driver rcar_i2c_driver = { .driver = { .name = "i2c-rcar", .owner = THIS_MODULE, @@ -702,7 +702,7 @@ static struct platform_driver rcar_i2c_drv = { .remove = __devexit_p(rcar_i2c_remove), }; -module_platform_driver(rcar_i2c_drv); +module_platform_driver(rcar_i2c_driver); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Renesas R-Car I2C bus driver"); diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c index b33d95ebc890..a290d089ceaf 100644 --- a/drivers/i2c/busses/i2c-s3c2410.c +++ b/drivers/i2c/busses/i2c-s3c2410.c @@ -38,6 +38,7 @@ #include <linux/io.h> #include <linux/of_i2c.h> #include <linux/of_gpio.h> +#include <linux/pinctrl/consumer.h> #include <asm/irq.h> @@ -49,6 +50,9 @@ #define QUIRK_HDMIPHY (1 << 1) #define QUIRK_NO_GPIO (1 << 2) +/* Max time to wait for bus to become idle after a xfer (in us) */ +#define S3C2410_IDLE_TIMEOUT 5000 + /* i2c controller state */ enum s3c24xx_i2c_state { STATE_IDLE, @@ -59,7 +63,6 @@ enum s3c24xx_i2c_state { }; struct s3c24xx_i2c { - spinlock_t lock; wait_queue_head_t wait; unsigned int quirks; unsigned int suspended:1; @@ -78,11 +81,11 @@ struct s3c24xx_i2c { void __iomem *regs; struct clk *clk; struct device *dev; - struct resource *ioarea; struct i2c_adapter adap; struct s3c2410_platform_i2c *pdata; int gpios[2]; + struct pinctrl *pctrl; #ifdef CONFIG_CPU_FREQ struct notifier_block freq_transition; #endif @@ -235,8 +238,47 @@ static inline void s3c24xx_i2c_stop(struct s3c24xx_i2c *i2c, int ret) dev_dbg(i2c->dev, "STOP\n"); - /* stop the transfer */ - iicstat &= ~S3C2410_IICSTAT_START; + /* + * The datasheet says that the STOP sequence should be: + * 1) I2CSTAT.5 = 0 - Clear BUSY (or 'generate STOP') + * 2) I2CCON.4 = 0 - Clear IRQPEND + * 3) Wait until the stop condition takes effect. + * 4*) I2CSTAT.4 = 0 - Clear TXRXEN + * + * Where, step "4*" is only for buses with the "HDMIPHY" quirk. + * + * However, after much experimentation, it appears that: + * a) normal buses automatically clear BUSY and transition from + * Master->Slave when they complete generating a STOP condition. + * Therefore, step (3) can be done in doxfer() by polling I2CCON.4 + * after starting the STOP generation here. + * b) HDMIPHY bus does neither, so there is no way to do step 3. + * There is no indication when this bus has finished generating + * STOP. + * + * In fact, we have found that as soon as the IRQPEND bit is cleared in + * step 2, the HDMIPHY bus generates the STOP condition, and then + * immediately starts transferring another data byte, even though the + * bus is supposedly stopped. This is presumably because the bus is + * still in "Master" mode, and its BUSY bit is still set. + * + * To avoid these extra post-STOP transactions on HDMI phy devices, we + * just disable Serial Output on the bus (I2CSTAT.4 = 0) directly, + * instead of first generating a proper STOP condition. This should + * float SDA & SCK terminating the transfer. Subsequent transfers + * start with a proper START condition, and proceed normally. + * + * The HDMIPHY bus is an internal bus that always has exactly two + * devices, the host as Master and the HDMIPHY device as the slave. + * Skipping the STOP condition has been tested on this bus and works. + */ + if (i2c->quirks & QUIRK_HDMIPHY) { + /* Stop driving the I2C pins */ + iicstat &= ~S3C2410_IICSTAT_TXRXEN; + } else { + /* stop the transfer */ + iicstat &= ~S3C2410_IICSTAT_START; + } writel(iicstat, i2c->regs + S3C2410_IICSTAT); i2c->state = STATE_STOP; @@ -490,13 +532,6 @@ static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c) unsigned long iicstat; int timeout = 400; - /* the timeout for HDMIPHY is reduced to 10 ms because - * the hangup is expected to happen, so waiting 400 ms - * causes only unnecessary system hangup - */ - if (i2c->quirks & QUIRK_HDMIPHY) - timeout = 10; - while (timeout-- > 0) { iicstat = readl(i2c->regs + S3C2410_IICSTAT); @@ -506,16 +541,61 @@ static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c) msleep(1); } - /* hang-up of bus dedicated for HDMIPHY occurred, resetting */ - if (i2c->quirks & QUIRK_HDMIPHY) { - writel(0, i2c->regs + S3C2410_IICCON); - writel(0, i2c->regs + S3C2410_IICSTAT); - writel(0, i2c->regs + S3C2410_IICDS); + return -ETIMEDOUT; +} - return 0; +/* s3c24xx_i2c_wait_idle + * + * wait for the i2c bus to become idle. +*/ + +static void s3c24xx_i2c_wait_idle(struct s3c24xx_i2c *i2c) +{ + unsigned long iicstat; + ktime_t start, now; + unsigned long delay; + int spins; + + /* ensure the stop has been through the bus */ + + dev_dbg(i2c->dev, "waiting for bus idle\n"); + + start = now = ktime_get(); + + /* + * Most of the time, the bus is already idle within a few usec of the + * end of a transaction. However, really slow i2c devices can stretch + * the clock, delaying STOP generation. + * + * On slower SoCs this typically happens within a very small number of + * instructions so busy wait briefly to avoid scheduling overhead. + */ + spins = 3; + iicstat = readl(i2c->regs + S3C2410_IICSTAT); + while ((iicstat & S3C2410_IICSTAT_START) && --spins) { + cpu_relax(); + iicstat = readl(i2c->regs + S3C2410_IICSTAT); } - return -ETIMEDOUT; + /* + * If we do get an appreciable delay as a compromise between idle + * detection latency for the normal, fast case, and system load in the + * slow device case, use an exponential back off in the polling loop, + * up to 1/10th of the total timeout, then continue to poll at a + * constant rate up to the timeout. + */ + delay = 1; + while ((iicstat & S3C2410_IICSTAT_START) && + ktime_us_delta(now, start) < S3C2410_IDLE_TIMEOUT) { + usleep_range(delay, 2 * delay); + if (delay < S3C2410_IDLE_TIMEOUT / 10) + delay <<= 1; + now = ktime_get(); + iicstat = readl(i2c->regs + S3C2410_IICSTAT); + } + + if (iicstat & S3C2410_IICSTAT_START) + dev_warn(i2c->dev, "timeout waiting for bus idle\n"); } /* s3c24xx_i2c_doxfer @@ -526,8 +606,7 @@ static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c) static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, struct i2c_msg *msgs, int num) { - unsigned long iicstat, timeout; - int spins = 20; + unsigned long timeout; int ret; if (i2c->suspended) @@ -540,8 +619,6 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, goto out; } - spin_lock_irq(&i2c->lock); - i2c->msg = msgs; i2c->msg_num = num; i2c->msg_ptr = 0; @@ -550,7 +627,6 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, s3c24xx_i2c_enable_irq(i2c); s3c24xx_i2c_message_start(i2c, msgs); - spin_unlock_irq(&i2c->lock); timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5); @@ -564,24 +640,11 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, 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 { - cpu_relax(); - iicstat = readl(i2c->regs + S3C2410_IICSTAT); - } while ((iicstat & S3C2410_IICSTAT_START) && --spins); - - /* if that timed out sleep */ - if (!spins) { - msleep(1); - iicstat = readl(i2c->regs + S3C2410_IICSTAT); - } + /* For QUIRK_HDMIPHY, bus is already disabled */ + if (i2c->quirks & QUIRK_HDMIPHY) + goto out; - if (iicstat & S3C2410_IICSTAT_START) - dev_warn(i2c->dev, "timeout waiting for bus idle\n"); + s3c24xx_i2c_wait_idle(i2c); out: return ret; @@ -740,7 +803,6 @@ static int s3c24xx_i2c_cpufreq_transition(struct notifier_block *nb, unsigned long val, void *data) { struct s3c24xx_i2c *i2c = freq_to_i2c(nb); - unsigned long flags; unsigned int got; int delta_f; int ret; @@ -754,9 +816,9 @@ static int s3c24xx_i2c_cpufreq_transition(struct notifier_block *nb, if ((val == CPUFREQ_POSTCHANGE && delta_f < 0) || (val == CPUFREQ_PRECHANGE && delta_f > 0)) { - spin_lock_irqsave(&i2c->lock, flags); + i2c_lock_adapter(&i2c->adap); ret = s3c24xx_i2c_clockrate(i2c, &got); - spin_unlock_irqrestore(&i2c->lock, flags); + i2c_unlock_adapter(&i2c->adap); if (ret < 0) dev_err(i2c->dev, "cannot find frequency\n"); @@ -858,14 +920,6 @@ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c) pdata = i2c->pdata; - /* inititalise the gpio */ - - if (pdata->cfg_gpio) - pdata->cfg_gpio(to_platform_device(i2c->dev)); - else - if (s3c24xx_i2c_parse_dt_gpio(i2c)) - return -EINVAL; - /* write slave address */ writeb(pdata->slave_addr, i2c->regs + S3C2410_IICADD); @@ -963,7 +1017,6 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev) i2c->adap.class = I2C_CLASS_HWMON | I2C_CLASS_SPD; i2c->tx_setup = 50; - spin_lock_init(&i2c->lock); init_waitqueue_head(&i2c->wait); /* find the clock and enable it */ @@ -989,36 +1042,38 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev) 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)); + i2c->regs = devm_request_and_ioremap(&pdev->dev, res); if (i2c->regs == NULL) { dev_err(&pdev->dev, "cannot map IO\n"); ret = -ENXIO; - goto err_ioarea; + goto err_clk; } - dev_dbg(&pdev->dev, "registers %p (%p, %p)\n", - i2c->regs, i2c->ioarea, res); + dev_dbg(&pdev->dev, "registers %p (%p)\n", + i2c->regs, res); /* setup info block for the i2c core */ i2c->adap.algo_data = i2c; i2c->adap.dev.parent = &pdev->dev; + i2c->pctrl = devm_pinctrl_get_select_default(i2c->dev); + + /* inititalise the i2c gpio lines */ + + if (i2c->pdata->cfg_gpio) { + i2c->pdata->cfg_gpio(to_platform_device(i2c->dev)); + } else if (IS_ERR(i2c->pctrl) && s3c24xx_i2c_parse_dt_gpio(i2c)) { + ret = -EINVAL; + goto err_clk; + } + /* initialise the i2c controller */ ret = s3c24xx_i2c_init(i2c); if (ret != 0) - goto err_iomap; + goto err_clk; /* find the IRQ for this unit (note, this relies on the init call to * ensure no current IRQs pending @@ -1027,7 +1082,7 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev) i2c->irq = ret = platform_get_irq(pdev, 0); if (ret <= 0) { dev_err(&pdev->dev, "cannot find IRQ\n"); - goto err_iomap; + goto err_clk; } ret = request_irq(i2c->irq, s3c24xx_i2c_irq, 0, @@ -1035,7 +1090,7 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev) if (ret != 0) { dev_err(&pdev->dev, "cannot claim IRQ %d\n", i2c->irq); - goto err_iomap; + goto err_clk; } ret = s3c24xx_i2c_register_cpufreq(i2c); @@ -1075,13 +1130,6 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev) 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_unprepare(i2c->clk); clk_put(i2c->clk); @@ -1110,16 +1158,13 @@ static int s3c24xx_i2c_remove(struct platform_device *pdev) clk_disable_unprepare(i2c->clk); clk_put(i2c->clk); - iounmap(i2c->regs); - - release_resource(i2c->ioarea); - s3c24xx_i2c_dt_gpio_free(i2c); - kfree(i2c->ioarea); + if (pdev->dev.of_node && IS_ERR(i2c->pctrl)) + s3c24xx_i2c_dt_gpio_free(i2c); return 0; } -#ifdef CONFIG_PM +#ifdef CONFIG_PM_SLEEP static int s3c24xx_i2c_suspend_noirq(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); @@ -1142,10 +1187,14 @@ static int s3c24xx_i2c_resume(struct device *dev) return 0; } +#endif +#ifdef CONFIG_PM static const struct dev_pm_ops s3c24xx_i2c_dev_pm_ops = { +#ifdef CONFIG_PM_SLEEP .suspend_noirq = s3c24xx_i2c_suspend_noirq, .resume = s3c24xx_i2c_resume, +#endif }; #define S3C24XX_DEV_PM_OPS (&s3c24xx_i2c_dev_pm_ops) diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c index 8110ca45f342..9411c1b892c0 100644 --- a/drivers/i2c/busses/i2c-sh_mobile.c +++ b/drivers/i2c/busses/i2c-sh_mobile.c @@ -120,11 +120,12 @@ struct sh_mobile_i2c_data { void __iomem *reg; struct i2c_adapter adap; unsigned long bus_speed; + unsigned int clks_per_count; struct clk *clk; u_int8_t icic; - u_int8_t iccl; - u_int8_t icch; u_int8_t flags; + u_int16_t iccl; + u_int16_t icch; spinlock_t lock; wait_queue_head_t wait; @@ -135,7 +136,8 @@ struct sh_mobile_i2c_data { #define IIC_FLAG_HAS_ICIC67 (1 << 0) -#define NORMAL_SPEED 100000 /* FAST_SPEED 400000 */ +#define STANDARD_MODE 100000 +#define FAST_MODE 400000 /* Register offsets */ #define ICDR 0x00 @@ -187,57 +189,90 @@ static void iic_set_clr(struct sh_mobile_i2c_data *pd, int offs, iic_wr(pd, offs, (iic_rd(pd, offs) | set) & ~clr); } -static void activate_ch(struct sh_mobile_i2c_data *pd) +static u32 sh_mobile_i2c_iccl(unsigned long count_khz, u32 tLOW, u32 tf, int offset) { - unsigned long i2c_clk; - u_int32_t num; - u_int32_t denom; - u_int32_t tmp; - - /* Wake up device and enable clock */ - pm_runtime_get_sync(pd->dev); - clk_enable(pd->clk); - - /* Get clock rate after clock is enabled */ - i2c_clk = clk_get_rate(pd->clk); + /* + * Conditional expression: + * ICCL >= COUNT_CLK * (tLOW + tf) + * + * SH-Mobile IIC hardware starts counting the LOW period of + * the SCL signal (tLOW) as soon as it pulls the SCL line. + * In order to meet the tLOW timing spec, we need to take into + * account the fall time of SCL signal (tf). Default tf value + * should be 0.3 us, for safety. + */ + return (((count_khz * (tLOW + tf)) + 5000) / 10000) + offset; +} - /* Calculate the value for iccl. From the data sheet: - * iccl = (p clock / transfer rate) * (L / (L + H)) - * where L and H are the SCL low/high ratio (5/4 in this case). - * We also round off the result. +static u32 sh_mobile_i2c_icch(unsigned long count_khz, u32 tHIGH, u32 tf, int offset) +{ + /* + * Conditional expression: + * ICCH >= COUNT_CLK * (tHIGH + tf) + * + * SH-Mobile IIC hardware is aware of SCL transition period 'tr', + * and can ignore it. SH-Mobile IIC controller starts counting + * the HIGH period of the SCL signal (tHIGH) after the SCL input + * voltage increases at VIH. + * + * Afterward it turned out calculating ICCH using only tHIGH spec + * will result in violation of the tHD;STA timing spec. We need + * to take into account the fall time of SDA signal (tf) at START + * condition, in order to meet both tHIGH and tHD;STA specs. */ - num = i2c_clk * 5; - denom = pd->bus_speed * 9; - tmp = num * 10 / denom; - if (tmp % 10 >= 5) - pd->iccl = (u_int8_t)((num/denom) + 1); - else - pd->iccl = (u_int8_t)(num/denom); + return (((count_khz * (tHIGH + tf)) + 5000) / 10000) + offset; +} - /* 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; +static void sh_mobile_i2c_init(struct sh_mobile_i2c_data *pd) +{ + unsigned long i2c_clk_khz; + u32 tHIGH, tLOW, tf; + int offset; + + /* Get clock rate after clock is enabled */ + clk_enable(pd->clk); + i2c_clk_khz = clk_get_rate(pd->clk) / 1000; + i2c_clk_khz /= pd->clks_per_count; + + if (pd->bus_speed == STANDARD_MODE) { + tLOW = 47; /* tLOW = 4.7 us */ + tHIGH = 40; /* tHD;STA = tHIGH = 4.0 us */ + tf = 3; /* tf = 0.3 us */ + offset = 0; /* No offset */ + } else if (pd->bus_speed == FAST_MODE) { + tLOW = 13; /* tLOW = 1.3 us */ + tHIGH = 6; /* tHD;STA = tHIGH = 0.6 us */ + tf = 3; /* tf = 0.3 us */ + offset = 0; /* No offset */ + } else { + dev_err(pd->dev, "unrecognized bus speed %lu Hz\n", + pd->bus_speed); + goto out; } - /* Calculate the value for icch. From the data sheet: - icch = (p clock / transfer rate) * (H / (L + H)) */ - num = i2c_clk * 4; - tmp = num * 10 / denom; - if (tmp % 10 >= 5) - pd->icch = (u_int8_t)((num/denom) + 1); + pd->iccl = sh_mobile_i2c_iccl(i2c_clk_khz, tLOW, tf, offset); + /* one more bit of ICCL in ICIC */ + if ((pd->iccl > 0xff) && (pd->flags & IIC_FLAG_HAS_ICIC67)) + pd->icic |= ICIC_ICCLB8; else - pd->icch = (u_int8_t)(num/denom); + pd->icic &= ~ICIC_ICCLB8; + pd->icch = sh_mobile_i2c_icch(i2c_clk_khz, tHIGH, tf, offset); /* 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; - } + if ((pd->icch > 0xff) && (pd->flags & IIC_FLAG_HAS_ICIC67)) + pd->icic |= ICIC_ICCHB8; + else + pd->icic &= ~ICIC_ICCHB8; + +out: + clk_disable(pd->clk); +} + +static void activate_ch(struct sh_mobile_i2c_data *pd) +{ + /* Wake up device and enable clock */ + pm_runtime_get_sync(pd->dev); + clk_enable(pd->clk); /* Enable channel and configure rx ack */ iic_set_clr(pd, ICCR, ICCR_ICE, 0); @@ -246,8 +281,8 @@ static void activate_ch(struct sh_mobile_i2c_data *pd) iic_wr(pd, ICIC, 0); /* Set the clock */ - iic_wr(pd, ICCL, pd->iccl); - iic_wr(pd, ICCH, pd->icch); + iic_wr(pd, ICCL, pd->iccl & 0xff); + iic_wr(pd, ICCH, pd->icch & 0xff); } static void deactivate_ch(struct sh_mobile_i2c_data *pd) @@ -434,6 +469,9 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id) wake_up(&pd->wait); } + /* defeat write posting to avoid spurious WAIT interrupts */ + iic_rd(pd, ICSR); + return IRQ_HANDLED; } @@ -451,8 +489,8 @@ static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg) iic_set_clr(pd, ICCR, ICCR_ICE, 0); /* Set the clock */ - iic_wr(pd, ICCL, pd->iccl); - iic_wr(pd, ICCH, pd->icch); + iic_wr(pd, ICCL, pd->iccl & 0xff); + iic_wr(pd, ICCH, pd->icch & 0xff); pd->msg = usr_msg; pd->pos = -1; @@ -621,10 +659,13 @@ static int sh_mobile_i2c_probe(struct platform_device *dev) goto err_irq; } - /* Use platformd data bus speed or NORMAL_SPEED */ - pd->bus_speed = NORMAL_SPEED; + /* Use platform data bus speed or STANDARD_MODE */ + pd->bus_speed = STANDARD_MODE; if (pdata && pdata->bus_speed) pd->bus_speed = pdata->bus_speed; + pd->clks_per_count = 1; + if (pdata && pdata->clks_per_count) + pd->clks_per_count = pdata->clks_per_count; /* The IIC blocks on SH-Mobile ARM processors * come with two new bits in ICIC. @@ -632,6 +673,8 @@ static int sh_mobile_i2c_probe(struct platform_device *dev) if (size > 0x17) pd->flags |= IIC_FLAG_HAS_ICIC67; + sh_mobile_i2c_init(pd); + /* Enable Runtime PM for this device. * * Also tell the Runtime PM core to ignore children @@ -667,8 +710,9 @@ static int sh_mobile_i2c_probe(struct platform_device *dev) goto err_all; } - dev_info(&dev->dev, "I2C adapter %d with bus speed %lu Hz\n", - adap->nr, pd->bus_speed); + dev_info(&dev->dev, + "I2C adapter %d with bus speed %lu Hz (L/H=%x/%x)\n", + adap->nr, pd->bus_speed, pd->iccl, pd->icch); of_i2c_register_devices(adap); return 0; diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c index 566a6757a33d..3b7bc06fe8a6 100644 --- a/drivers/i2c/muxes/i2c-mux-gpio.c +++ b/drivers/i2c/muxes/i2c-mux-gpio.c @@ -16,6 +16,8 @@ #include <linux/module.h> #include <linux/slab.h> #include <linux/gpio.h> +#include <linux/of_i2c.h> +#include <linux/of_gpio.h> struct gpiomux { struct i2c_adapter *parent; @@ -57,29 +59,110 @@ static int __devinit match_gpio_chip_by_label(struct gpio_chip *chip, return !strcmp(chip->label, data); } +#ifdef CONFIG_OF +static int __devinit i2c_mux_gpio_probe_dt(struct gpiomux *mux, + struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct device_node *adapter_np, *child; + struct i2c_adapter *adapter; + unsigned *values, *gpios; + int i = 0; + + if (!np) + return -ENODEV; + + adapter_np = of_parse_phandle(np, "i2c-parent", 0); + if (!adapter_np) { + dev_err(&pdev->dev, "Cannot parse i2c-parent\n"); + return -ENODEV; + } + adapter = of_find_i2c_adapter_by_node(adapter_np); + if (!adapter) { + dev_err(&pdev->dev, "Cannot find parent bus\n"); + return -ENODEV; + } + mux->data.parent = i2c_adapter_id(adapter); + put_device(&adapter->dev); + + mux->data.n_values = of_get_child_count(np); + + values = devm_kzalloc(&pdev->dev, + sizeof(*mux->data.values) * mux->data.n_values, + GFP_KERNEL); + if (!values) { + dev_err(&pdev->dev, "Cannot allocate values array"); + return -ENOMEM; + } + + for_each_child_of_node(np, child) { + of_property_read_u32(child, "reg", values + i); + i++; + } + mux->data.values = values; + + if (of_property_read_u32(np, "idle-state", &mux->data.idle)) + mux->data.idle = I2C_MUX_GPIO_NO_IDLE; + + mux->data.n_gpios = of_gpio_named_count(np, "mux-gpios"); + if (mux->data.n_gpios < 0) { + dev_err(&pdev->dev, "Missing mux-gpios property in the DT.\n"); + return -EINVAL; + } + + gpios = devm_kzalloc(&pdev->dev, + sizeof(*mux->data.gpios) * mux->data.n_gpios, GFP_KERNEL); + if (!gpios) { + dev_err(&pdev->dev, "Cannot allocate gpios array"); + return -ENOMEM; + } + + for (i = 0; i < mux->data.n_gpios; i++) + gpios[i] = of_get_named_gpio(np, "mux-gpios", i); + + mux->data.gpios = gpios; + + return 0; +} +#else +static int __devinit i2c_mux_gpio_probe_dt(struct gpiomux *mux, + struct platform_device *pdev) +{ + return 0; +} +#endif + static int __devinit i2c_mux_gpio_probe(struct platform_device *pdev) { struct gpiomux *mux; - struct i2c_mux_gpio_platform_data *pdata; struct i2c_adapter *parent; int (*deselect) (struct i2c_adapter *, void *, u32); unsigned initial_state, gpio_base; int i, ret; - pdata = pdev->dev.platform_data; - if (!pdata) { - dev_err(&pdev->dev, "Missing platform data\n"); - return -ENODEV; + mux = devm_kzalloc(&pdev->dev, sizeof(*mux), GFP_KERNEL); + if (!mux) { + dev_err(&pdev->dev, "Cannot allocate gpiomux structure"); + return -ENOMEM; } + platform_set_drvdata(pdev, mux); + + if (!pdev->dev.platform_data) { + ret = i2c_mux_gpio_probe_dt(mux, pdev); + if (ret < 0) + return ret; + } else + memcpy(&mux->data, pdev->dev.platform_data, sizeof(mux->data)); + /* * If a GPIO chip name is provided, the GPIO pin numbers provided are * relative to its base GPIO number. Otherwise they are absolute. */ - if (pdata->gpio_chip) { + if (mux->data.gpio_chip) { struct gpio_chip *gpio; - gpio = gpiochip_find(pdata->gpio_chip, + gpio = gpiochip_find(mux->data.gpio_chip, match_gpio_chip_by_label); if (!gpio) return -EPROBE_DEFER; @@ -89,49 +172,44 @@ static int __devinit i2c_mux_gpio_probe(struct platform_device *pdev) gpio_base = 0; } - parent = i2c_get_adapter(pdata->parent); + parent = i2c_get_adapter(mux->data.parent); if (!parent) { dev_err(&pdev->dev, "Parent adapter (%d) not found\n", - pdata->parent); + mux->data.parent); return -ENODEV; } - mux = devm_kzalloc(&pdev->dev, sizeof(*mux), GFP_KERNEL); - if (!mux) { - ret = -ENOMEM; - goto alloc_failed; - } - mux->parent = parent; - mux->data = *pdata; mux->gpio_base = gpio_base; + mux->adap = devm_kzalloc(&pdev->dev, - sizeof(*mux->adap) * pdata->n_values, + sizeof(*mux->adap) * mux->data.n_values, GFP_KERNEL); if (!mux->adap) { + dev_err(&pdev->dev, "Cannot allocate i2c_adapter structure"); ret = -ENOMEM; goto alloc_failed; } - if (pdata->idle != I2C_MUX_GPIO_NO_IDLE) { - initial_state = pdata->idle; + if (mux->data.idle != I2C_MUX_GPIO_NO_IDLE) { + initial_state = mux->data.idle; deselect = i2c_mux_gpio_deselect; } else { - initial_state = pdata->values[0]; + initial_state = mux->data.values[0]; deselect = NULL; } - for (i = 0; i < pdata->n_gpios; i++) { - ret = gpio_request(gpio_base + pdata->gpios[i], "i2c-mux-gpio"); + for (i = 0; i < mux->data.n_gpios; i++) { + ret = gpio_request(gpio_base + mux->data.gpios[i], "i2c-mux-gpio"); if (ret) goto err_request_gpio; - gpio_direction_output(gpio_base + pdata->gpios[i], + gpio_direction_output(gpio_base + mux->data.gpios[i], initial_state & (1 << i)); } - for (i = 0; i < pdata->n_values; i++) { - u32 nr = pdata->base_nr ? (pdata->base_nr + i) : 0; - unsigned int class = pdata->classes ? pdata->classes[i] : 0; + for (i = 0; i < mux->data.n_values; i++) { + u32 nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0; + unsigned int class = mux->data.classes ? mux->data.classes[i] : 0; mux->adap[i] = i2c_add_mux_adapter(parent, &pdev->dev, mux, nr, i, class, @@ -144,19 +222,17 @@ static int __devinit i2c_mux_gpio_probe(struct platform_device *pdev) } dev_info(&pdev->dev, "%d port mux on %s adapter\n", - pdata->n_values, parent->name); - - platform_set_drvdata(pdev, mux); + mux->data.n_values, parent->name); return 0; add_adapter_failed: for (; i > 0; i--) i2c_del_mux_adapter(mux->adap[i - 1]); - i = pdata->n_gpios; + i = mux->data.n_gpios; err_request_gpio: for (; i > 0; i--) - gpio_free(gpio_base + pdata->gpios[i - 1]); + gpio_free(gpio_base + mux->data.gpios[i - 1]); alloc_failed: i2c_put_adapter(parent); @@ -180,12 +256,19 @@ static int __devexit i2c_mux_gpio_remove(struct platform_device *pdev) return 0; } +static const struct of_device_id i2c_mux_gpio_of_match[] __devinitconst = { + { .compatible = "i2c-mux-gpio", }, + {}, +}; +MODULE_DEVICE_TABLE(of, i2c_mux_gpio_of_match); + static struct platform_driver i2c_mux_gpio_driver = { .probe = i2c_mux_gpio_probe, .remove = __devexit_p(i2c_mux_gpio_remove), .driver = { .owner = THIS_MODULE, .name = "i2c-mux-gpio", + .of_match_table = of_match_ptr(i2c_mux_gpio_of_match), }, }; |