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author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-02-04 21:57:43 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-02-04 21:57:43 +0300 |
commit | 4141cf676b9e345d3ddeb1710dd3156a09c50244 (patch) | |
tree | 4b2b6249e99efdd47eafa5780f106d593f64708b /drivers/misc/eeprom | |
parent | 3462ac57033e79a87dbae2497773f22b9c536fbc (diff) | |
parent | e38c85644e11c6dc5a39305c96b617f63403423d (diff) | |
download | linux-4141cf676b9e345d3ddeb1710dd3156a09c50244.tar.xz |
Merge branch 'i2c/for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
"I2C has the following changes for you:
- new flag to mark DMA safe buffers in i2c_msg. Also, some
infrastructure around it. And docs.
- huge refactoring of the at24 driver led by the new maintainer
Bartosz
- update I2C bus recovery to send STOP after recovery
- conversion from gpio to gpiod for I2C bus recovery
- adding a fault-injector to the i2c-gpio driver
- lots of small driver improvements, and bigger ones to
i2c-sh_mobile"
* 'i2c/for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (99 commits)
i2c: mv64xxx: Add myself as maintainer for this driver
i2c: mv64xxx: Fix clock resource by adding an optional bus clock
i2c: mv64xxx: Remove useless test before clk_disable_unprepare
i2c: mxs: use true and false for boolean values
i2c: meson: update doc description to fix build warnings
i2c: meson: add configurable divider factors
dt-bindings: i2c: update documentation for the Meson-AXG
i2c: imx-lpi2c: add runtime pm support
i2c: rcar: fix some trivial typos in comments
i2c: davinci: fix the cpufreq transition
i2c: rk3x: add proper kerneldoc header
i2c: rk3x: account for const type of of_device_id.data
i2c: acorn: remove outdated path from file header
i2c: acorn: add MODULE_LICENSE tag
i2c: rcar: implement bus recovery
i2c: send STOP after successful bus recovery
i2c: ensure SDA is released in recovery if SDA is controllable
i2c: add 'set_sda' to bus_recovery_info
i2c: add identifier in declarations for i2c_bus_recovery
i2c: make kerneldoc about bus recovery more precise
...
Diffstat (limited to 'drivers/misc/eeprom')
-rw-r--r-- | drivers/misc/eeprom/Kconfig | 1 | ||||
-rw-r--r-- | drivers/misc/eeprom/at24.c | 731 |
2 files changed, 255 insertions, 477 deletions
diff --git a/drivers/misc/eeprom/Kconfig b/drivers/misc/eeprom/Kconfig index de58762097c4..68a1ac929917 100644 --- a/drivers/misc/eeprom/Kconfig +++ b/drivers/misc/eeprom/Kconfig @@ -4,6 +4,7 @@ config EEPROM_AT24 tristate "I2C EEPROMs / RAMs / ROMs from most vendors" depends on I2C && SYSFS select NVMEM + select REGMAP_I2C help Enable this driver to get read/write support to most I2C EEPROMs and compatible devices like FRAMs, SRAMs, ROMs etc. After you diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c index 4d63ac8a82e0..01f9c4921c50 100644 --- a/drivers/misc/eeprom/at24.c +++ b/drivers/misc/eeprom/at24.c @@ -24,8 +24,10 @@ #include <linux/acpi.h> #include <linux/i2c.h> #include <linux/nvmem-provider.h> +#include <linux/regmap.h> #include <linux/platform_data/at24.h> #include <linux/pm_runtime.h> +#include <linux/gpio/consumer.h> /* * I2C EEPROMs from most vendors are inexpensive and mostly interchangeable. @@ -55,14 +57,13 @@ * which won't work on pure SMBus systems. */ +struct at24_client { + struct i2c_client *client; + struct regmap *regmap; +}; + struct at24_data { struct at24_platform_data chip; - int use_smbus; - int use_smbus_write; - - ssize_t (*read_func)(struct at24_data *, char *, unsigned int, size_t); - ssize_t (*write_func)(struct at24_data *, - const char *, unsigned int, size_t); /* * Lock protects against activities from other Linux tasks, @@ -70,18 +71,20 @@ struct at24_data { */ struct mutex lock; - u8 *writebuf; - unsigned write_max; - unsigned num_addresses; + unsigned int write_max; + unsigned int num_addresses; + unsigned int offset_adj; struct nvmem_config nvmem_config; struct nvmem_device *nvmem; + struct gpio_desc *wp_gpio; + /* * Some chips tie up multiple I2C addresses; dummy devices reserve * them for us, and we'll use them with SMBus calls. */ - struct i2c_client *client[]; + struct at24_client client[]; }; /* @@ -93,27 +96,17 @@ struct at24_data { * * This value is forced to be a power of two so that writes align on pages. */ -static unsigned io_limit = 128; -module_param(io_limit, uint, 0); -MODULE_PARM_DESC(io_limit, "Maximum bytes per I/O (default 128)"); +static unsigned int at24_io_limit = 128; +module_param_named(io_limit, at24_io_limit, uint, 0); +MODULE_PARM_DESC(at24_io_limit, "Maximum bytes per I/O (default 128)"); /* * Specs often allow 5 msec for a page write, sometimes 20 msec; * it's important to recover from write timeouts. */ -static unsigned write_timeout = 25; -module_param(write_timeout, uint, 0); -MODULE_PARM_DESC(write_timeout, "Time (in ms) to try writes (default 25)"); - -#define AT24_SIZE_BYTELEN 5 -#define AT24_SIZE_FLAGS 8 - -#define AT24_BITMASK(x) (BIT(x) - 1) - -/* create non-zero magic value for given eeprom parameters */ -#define AT24_DEVICE_MAGIC(_len, _flags) \ - ((1 << AT24_SIZE_FLAGS | (_flags)) \ - << AT24_SIZE_BYTELEN | ilog2(_len)) +static unsigned int at24_write_timeout = 25; +module_param_named(write_timeout, at24_write_timeout, uint, 0); +MODULE_PARM_DESC(at24_write_timeout, "Time (in ms) to try writes (default 25)"); /* * Both reads and writes fail if the previous write didn't complete yet. This @@ -126,118 +119,123 @@ MODULE_PARM_DESC(write_timeout, "Time (in ms) to try writes (default 25)"); * iteration of processing the request. Both should be unsigned integers * holding at least 32 bits. */ -#define loop_until_timeout(tout, op_time) \ - for (tout = jiffies + msecs_to_jiffies(write_timeout), op_time = 0; \ +#define at24_loop_until_timeout(tout, op_time) \ + for (tout = jiffies + msecs_to_jiffies(at24_write_timeout), \ + op_time = 0; \ op_time ? time_before(op_time, tout) : true; \ usleep_range(1000, 1500), op_time = jiffies) +struct at24_chip_data { + /* + * these fields mirror their equivalents in + * struct at24_platform_data + */ + u32 byte_len; + u8 flags; +}; + +#define AT24_CHIP_DATA(_name, _len, _flags) \ + static const struct at24_chip_data _name = { \ + .byte_len = _len, .flags = _flags, \ + } + +/* needs 8 addresses as A0-A2 are ignored */ +AT24_CHIP_DATA(at24_data_24c00, 128 / 8, AT24_FLAG_TAKE8ADDR); +/* old variants can't be handled with this generic entry! */ +AT24_CHIP_DATA(at24_data_24c01, 1024 / 8, 0); +AT24_CHIP_DATA(at24_data_24cs01, 16, + AT24_FLAG_SERIAL | AT24_FLAG_READONLY); +AT24_CHIP_DATA(at24_data_24c02, 2048 / 8, 0); +AT24_CHIP_DATA(at24_data_24cs02, 16, + AT24_FLAG_SERIAL | AT24_FLAG_READONLY); +AT24_CHIP_DATA(at24_data_24mac402, 48 / 8, + AT24_FLAG_MAC | AT24_FLAG_READONLY); +AT24_CHIP_DATA(at24_data_24mac602, 64 / 8, + AT24_FLAG_MAC | AT24_FLAG_READONLY); +/* spd is a 24c02 in memory DIMMs */ +AT24_CHIP_DATA(at24_data_spd, 2048 / 8, + AT24_FLAG_READONLY | AT24_FLAG_IRUGO); +AT24_CHIP_DATA(at24_data_24c04, 4096 / 8, 0); +AT24_CHIP_DATA(at24_data_24cs04, 16, + AT24_FLAG_SERIAL | AT24_FLAG_READONLY); +/* 24rf08 quirk is handled at i2c-core */ +AT24_CHIP_DATA(at24_data_24c08, 8192 / 8, 0); +AT24_CHIP_DATA(at24_data_24cs08, 16, + AT24_FLAG_SERIAL | AT24_FLAG_READONLY); +AT24_CHIP_DATA(at24_data_24c16, 16384 / 8, 0); +AT24_CHIP_DATA(at24_data_24cs16, 16, + AT24_FLAG_SERIAL | AT24_FLAG_READONLY); +AT24_CHIP_DATA(at24_data_24c32, 32768 / 8, AT24_FLAG_ADDR16); +AT24_CHIP_DATA(at24_data_24cs32, 16, + AT24_FLAG_ADDR16 | AT24_FLAG_SERIAL | AT24_FLAG_READONLY); +AT24_CHIP_DATA(at24_data_24c64, 65536 / 8, AT24_FLAG_ADDR16); +AT24_CHIP_DATA(at24_data_24cs64, 16, + AT24_FLAG_ADDR16 | AT24_FLAG_SERIAL | AT24_FLAG_READONLY); +AT24_CHIP_DATA(at24_data_24c128, 131072 / 8, AT24_FLAG_ADDR16); +AT24_CHIP_DATA(at24_data_24c256, 262144 / 8, AT24_FLAG_ADDR16); +AT24_CHIP_DATA(at24_data_24c512, 524288 / 8, AT24_FLAG_ADDR16); +AT24_CHIP_DATA(at24_data_24c1024, 1048576 / 8, AT24_FLAG_ADDR16); +/* identical to 24c08 ? */ +AT24_CHIP_DATA(at24_data_INT3499, 8192 / 8, 0); + static const struct i2c_device_id at24_ids[] = { - /* needs 8 addresses as A0-A2 are ignored */ - { "24c00", AT24_DEVICE_MAGIC(128 / 8, AT24_FLAG_TAKE8ADDR) }, - /* old variants can't be handled with this generic entry! */ - { "24c01", AT24_DEVICE_MAGIC(1024 / 8, 0) }, - { "24cs01", AT24_DEVICE_MAGIC(16, - AT24_FLAG_SERIAL | AT24_FLAG_READONLY) }, - { "24c02", AT24_DEVICE_MAGIC(2048 / 8, 0) }, - { "24cs02", AT24_DEVICE_MAGIC(16, - AT24_FLAG_SERIAL | AT24_FLAG_READONLY) }, - { "24mac402", AT24_DEVICE_MAGIC(48 / 8, - AT24_FLAG_MAC | AT24_FLAG_READONLY) }, - { "24mac602", AT24_DEVICE_MAGIC(64 / 8, - AT24_FLAG_MAC | AT24_FLAG_READONLY) }, - /* spd is a 24c02 in memory DIMMs */ - { "spd", AT24_DEVICE_MAGIC(2048 / 8, - AT24_FLAG_READONLY | AT24_FLAG_IRUGO) }, - { "24c04", AT24_DEVICE_MAGIC(4096 / 8, 0) }, - { "24cs04", AT24_DEVICE_MAGIC(16, - AT24_FLAG_SERIAL | AT24_FLAG_READONLY) }, - /* 24rf08 quirk is handled at i2c-core */ - { "24c08", AT24_DEVICE_MAGIC(8192 / 8, 0) }, - { "24cs08", AT24_DEVICE_MAGIC(16, - AT24_FLAG_SERIAL | AT24_FLAG_READONLY) }, - { "24c16", AT24_DEVICE_MAGIC(16384 / 8, 0) }, - { "24cs16", AT24_DEVICE_MAGIC(16, - AT24_FLAG_SERIAL | AT24_FLAG_READONLY) }, - { "24c32", AT24_DEVICE_MAGIC(32768 / 8, AT24_FLAG_ADDR16) }, - { "24cs32", AT24_DEVICE_MAGIC(16, - AT24_FLAG_ADDR16 | - AT24_FLAG_SERIAL | - AT24_FLAG_READONLY) }, - { "24c64", AT24_DEVICE_MAGIC(65536 / 8, AT24_FLAG_ADDR16) }, - { "24cs64", AT24_DEVICE_MAGIC(16, - AT24_FLAG_ADDR16 | - AT24_FLAG_SERIAL | - AT24_FLAG_READONLY) }, - { "24c128", AT24_DEVICE_MAGIC(131072 / 8, AT24_FLAG_ADDR16) }, - { "24c256", AT24_DEVICE_MAGIC(262144 / 8, AT24_FLAG_ADDR16) }, - { "24c512", AT24_DEVICE_MAGIC(524288 / 8, AT24_FLAG_ADDR16) }, - { "24c1024", AT24_DEVICE_MAGIC(1048576 / 8, AT24_FLAG_ADDR16) }, - { "at24", 0 }, + { "24c00", (kernel_ulong_t)&at24_data_24c00 }, + { "24c01", (kernel_ulong_t)&at24_data_24c01 }, + { "24cs01", (kernel_ulong_t)&at24_data_24cs01 }, + { "24c02", (kernel_ulong_t)&at24_data_24c02 }, + { "24cs02", (kernel_ulong_t)&at24_data_24cs02 }, + { "24mac402", (kernel_ulong_t)&at24_data_24mac402 }, + { "24mac602", (kernel_ulong_t)&at24_data_24mac602 }, + { "spd", (kernel_ulong_t)&at24_data_spd }, + { "24c04", (kernel_ulong_t)&at24_data_24c04 }, + { "24cs04", (kernel_ulong_t)&at24_data_24cs04 }, + { "24c08", (kernel_ulong_t)&at24_data_24c08 }, + { "24cs08", (kernel_ulong_t)&at24_data_24cs08 }, + { "24c16", (kernel_ulong_t)&at24_data_24c16 }, + { "24cs16", (kernel_ulong_t)&at24_data_24cs16 }, + { "24c32", (kernel_ulong_t)&at24_data_24c32 }, + { "24cs32", (kernel_ulong_t)&at24_data_24cs32 }, + { "24c64", (kernel_ulong_t)&at24_data_24c64 }, + { "24cs64", (kernel_ulong_t)&at24_data_24cs64 }, + { "24c128", (kernel_ulong_t)&at24_data_24c128 }, + { "24c256", (kernel_ulong_t)&at24_data_24c256 }, + { "24c512", (kernel_ulong_t)&at24_data_24c512 }, + { "24c1024", (kernel_ulong_t)&at24_data_24c1024 }, + { "at24", 0 }, { /* END OF LIST */ } }; MODULE_DEVICE_TABLE(i2c, at24_ids); static const struct of_device_id at24_of_match[] = { - { - .compatible = "atmel,24c00", - .data = (void *)AT24_DEVICE_MAGIC(128 / 8, AT24_FLAG_TAKE8ADDR) - }, - { - .compatible = "atmel,24c01", - .data = (void *)AT24_DEVICE_MAGIC(1024 / 8, 0) - }, - { - .compatible = "atmel,24c02", - .data = (void *)AT24_DEVICE_MAGIC(2048 / 8, 0) - }, - { - .compatible = "atmel,spd", - .data = (void *)AT24_DEVICE_MAGIC(2048 / 8, - AT24_FLAG_READONLY | AT24_FLAG_IRUGO) - }, - { - .compatible = "atmel,24c04", - .data = (void *)AT24_DEVICE_MAGIC(4096 / 8, 0) - }, - { - .compatible = "atmel,24c08", - .data = (void *)AT24_DEVICE_MAGIC(8192 / 8, 0) - }, - { - .compatible = "atmel,24c16", - .data = (void *)AT24_DEVICE_MAGIC(16384 / 8, 0) - }, - { - .compatible = "atmel,24c32", - .data = (void *)AT24_DEVICE_MAGIC(32768 / 8, AT24_FLAG_ADDR16) - }, - { - .compatible = "atmel,24c64", - .data = (void *)AT24_DEVICE_MAGIC(65536 / 8, AT24_FLAG_ADDR16) - }, - { - .compatible = "atmel,24c128", - .data = (void *)AT24_DEVICE_MAGIC(131072 / 8, AT24_FLAG_ADDR16) - }, - { - .compatible = "atmel,24c256", - .data = (void *)AT24_DEVICE_MAGIC(262144 / 8, AT24_FLAG_ADDR16) - }, - { - .compatible = "atmel,24c512", - .data = (void *)AT24_DEVICE_MAGIC(524288 / 8, AT24_FLAG_ADDR16) - }, - { - .compatible = "atmel,24c1024", - .data = (void *)AT24_DEVICE_MAGIC(1048576 / 8, AT24_FLAG_ADDR16) - }, - { }, + { .compatible = "atmel,24c00", .data = &at24_data_24c00 }, + { .compatible = "atmel,24c01", .data = &at24_data_24c01 }, + { .compatible = "atmel,24cs01", .data = &at24_data_24cs01 }, + { .compatible = "atmel,24c02", .data = &at24_data_24c02 }, + { .compatible = "atmel,24cs02", .data = &at24_data_24cs02 }, + { .compatible = "atmel,24mac402", .data = &at24_data_24mac402 }, + { .compatible = "atmel,24mac602", .data = &at24_data_24mac602 }, + { .compatible = "atmel,spd", .data = &at24_data_spd }, + { .compatible = "atmel,24c04", .data = &at24_data_24c04 }, + { .compatible = "atmel,24cs04", .data = &at24_data_24cs04 }, + { .compatible = "atmel,24c08", .data = &at24_data_24c08 }, + { .compatible = "atmel,24cs08", .data = &at24_data_24cs08 }, + { .compatible = "atmel,24c16", .data = &at24_data_24c16 }, + { .compatible = "atmel,24cs16", .data = &at24_data_24cs16 }, + { .compatible = "atmel,24c32", .data = &at24_data_24c32 }, + { .compatible = "atmel,24cs32", .data = &at24_data_24cs32 }, + { .compatible = "atmel,24c64", .data = &at24_data_24c64 }, + { .compatible = "atmel,24cs64", .data = &at24_data_24cs64 }, + { .compatible = "atmel,24c128", .data = &at24_data_24c128 }, + { .compatible = "atmel,24c256", .data = &at24_data_24c256 }, + { .compatible = "atmel,24c512", .data = &at24_data_24c512 }, + { .compatible = "atmel,24c1024", .data = &at24_data_24c1024 }, + { /* END OF LIST */ }, }; MODULE_DEVICE_TABLE(of, at24_of_match); static const struct acpi_device_id at24_acpi_ids[] = { - { "INT3499", AT24_DEVICE_MAGIC(8192 / 8, 0) }, - { } + { "INT3499", (kernel_ulong_t)&at24_data_INT3499 }, + { /* END OF LIST */ } }; MODULE_DEVICE_TABLE(acpi, at24_acpi_ids); @@ -251,20 +249,11 @@ MODULE_DEVICE_TABLE(acpi, at24_acpi_ids); * Slave address and byte offset derive from the offset. Always * set the byte address; on a multi-master board, another master * may have changed the chip's "current" address pointer. - * - * REVISIT some multi-address chips don't rollover page reads to - * the next slave address, so we may need to truncate the count. - * Those chips might need another quirk flag. - * - * If the real hardware used four adjacent 24c02 chips and that - * were misconfigured as one 24c08, that would be a similar effect: - * one "eeprom" file not four, but larger reads would fail when - * they crossed certain pages. */ -static struct i2c_client *at24_translate_offset(struct at24_data *at24, - unsigned int *offset) +static struct at24_client *at24_translate_offset(struct at24_data *at24, + unsigned int *offset) { - unsigned i; + unsigned int i; if (at24->chip.flags & AT24_FLAG_ADDR16) { i = *offset >> 16; @@ -274,168 +263,55 @@ static struct i2c_client *at24_translate_offset(struct at24_data *at24, *offset &= 0xff; } - return at24->client[i]; + return &at24->client[i]; } -static ssize_t at24_eeprom_read_smbus(struct at24_data *at24, char *buf, +static size_t at24_adjust_read_count(struct at24_data *at24, unsigned int offset, size_t count) { - unsigned long timeout, read_time; - struct i2c_client *client; - int status; - - client = at24_translate_offset(at24, &offset); - - if (count > io_limit) - count = io_limit; - - /* Smaller eeproms can work given some SMBus extension calls */ - if (count > I2C_SMBUS_BLOCK_MAX) - count = I2C_SMBUS_BLOCK_MAX; - - loop_until_timeout(timeout, read_time) { - status = i2c_smbus_read_i2c_block_data_or_emulated(client, - offset, - count, buf); - - dev_dbg(&client->dev, "read %zu@%d --> %d (%ld)\n", - count, offset, status, jiffies); - - if (status == count) - return count; - } - - return -ETIMEDOUT; -} - -static ssize_t at24_eeprom_read_i2c(struct at24_data *at24, char *buf, - unsigned int offset, size_t count) -{ - unsigned long timeout, read_time; - struct i2c_client *client; - struct i2c_msg msg[2]; - int status, i; - u8 msgbuf[2]; - - memset(msg, 0, sizeof(msg)); - client = at24_translate_offset(at24, &offset); - - if (count > io_limit) - count = io_limit; + unsigned int bits; + size_t remainder; /* - * When we have a better choice than SMBus calls, use a combined I2C - * message. Write address; then read up to io_limit data bytes. Note - * that read page rollover helps us here (unlike writes). msgbuf is - * u8 and will cast to our needs. + * In case of multi-address chips that don't rollover reads to + * the next slave address: truncate the count to the slave boundary, + * so that the read never straddles slaves. */ - i = 0; - if (at24->chip.flags & AT24_FLAG_ADDR16) - msgbuf[i++] = offset >> 8; - msgbuf[i++] = offset; - - msg[0].addr = client->addr; - msg[0].buf = msgbuf; - msg[0].len = i; - - msg[1].addr = client->addr; - msg[1].flags = I2C_M_RD; - msg[1].buf = buf; - msg[1].len = count; - - loop_until_timeout(timeout, read_time) { - status = i2c_transfer(client->adapter, msg, 2); - if (status == 2) - status = count; - - dev_dbg(&client->dev, "read %zu@%d --> %d (%ld)\n", - count, offset, status, jiffies); - - if (status == count) - return count; + if (at24->chip.flags & AT24_FLAG_NO_RDROL) { + bits = (at24->chip.flags & AT24_FLAG_ADDR16) ? 16 : 8; + remainder = BIT(bits) - offset; + if (count > remainder) + count = remainder; } - return -ETIMEDOUT; + if (count > at24_io_limit) + count = at24_io_limit; + + return count; } -static ssize_t at24_eeprom_read_serial(struct at24_data *at24, char *buf, - unsigned int offset, size_t count) +static ssize_t at24_regmap_read(struct at24_data *at24, char *buf, + unsigned int offset, size_t count) { unsigned long timeout, read_time; + struct at24_client *at24_client; struct i2c_client *client; - struct i2c_msg msg[2]; - u8 addrbuf[2]; - int status; - - client = at24_translate_offset(at24, &offset); - - memset(msg, 0, sizeof(msg)); - msg[0].addr = client->addr; - msg[0].buf = addrbuf; - - /* - * The address pointer of the device is shared between the regular - * EEPROM array and the serial number block. The dummy write (part of - * the sequential read protocol) ensures the address pointer is reset - * to the desired position. - */ - if (at24->chip.flags & AT24_FLAG_ADDR16) { - /* - * For 16 bit address pointers, the word address must contain - * a '10' sequence in bits 11 and 10 regardless of the - * intended position of the address pointer. - */ - addrbuf[0] = 0x08; - addrbuf[1] = offset; - msg[0].len = 2; - } else { - /* - * Otherwise the word address must begin with a '10' sequence, - * regardless of the intended address. - */ - addrbuf[0] = 0x80 + offset; - msg[0].len = 1; - } - - msg[1].addr = client->addr; - msg[1].flags = I2C_M_RD; - msg[1].buf = buf; - msg[1].len = count; + struct regmap *regmap; + int ret; - loop_until_timeout(timeout, read_time) { - status = i2c_transfer(client->adapter, msg, 2); - if (status == 2) - return count; - } + at24_client = at24_translate_offset(at24, &offset); + regmap = at24_client->regmap; + client = at24_client->client; + count = at24_adjust_read_count(at24, offset, count); - return -ETIMEDOUT; -} + /* adjust offset for mac and serial read ops */ + offset += at24->offset_adj; -static ssize_t at24_eeprom_read_mac(struct at24_data *at24, char *buf, - unsigned int offset, size_t count) -{ - unsigned long timeout, read_time; - struct i2c_client *client; - struct i2c_msg msg[2]; - u8 addrbuf[2]; - int status; - - client = at24_translate_offset(at24, &offset); - - memset(msg, 0, sizeof(msg)); - msg[0].addr = client->addr; - msg[0].buf = addrbuf; - /* EUI-48 starts from 0x9a, EUI-64 from 0x98 */ - addrbuf[0] = 0xa0 - at24->chip.byte_len + offset; - msg[0].len = 1; - msg[1].addr = client->addr; - msg[1].flags = I2C_M_RD; - msg[1].buf = buf; - msg[1].len = count; - - loop_until_timeout(timeout, read_time) { - status = i2c_transfer(client->adapter, msg, 2); - if (status == 2) + at24_loop_until_timeout(timeout, read_time) { + ret = regmap_bulk_read(regmap, offset, buf, count); + dev_dbg(&client->dev, "read %zu@%d --> %d (%ld)\n", + count, offset, ret, jiffies); + if (!ret) return count; } @@ -454,7 +330,7 @@ static ssize_t at24_eeprom_read_mac(struct at24_data *at24, char *buf, static size_t at24_adjust_write_count(struct at24_data *at24, unsigned int offset, size_t count) { - unsigned next_page; + unsigned int next_page; /* write_max is at most a page */ if (count > at24->write_max) @@ -468,91 +344,25 @@ static size_t at24_adjust_write_count(struct at24_data *at24, return count; } -static ssize_t at24_eeprom_write_smbus_block(struct at24_data *at24, - const char *buf, - unsigned int offset, size_t count) +static ssize_t at24_regmap_write(struct at24_data *at24, const char *buf, + unsigned int offset, size_t count) { unsigned long timeout, write_time; + struct at24_client *at24_client; struct i2c_client *client; - ssize_t status = 0; - - client = at24_translate_offset(at24, &offset); - count = at24_adjust_write_count(at24, offset, count); - - loop_until_timeout(timeout, write_time) { - status = i2c_smbus_write_i2c_block_data(client, - offset, count, buf); - if (status == 0) - status = count; - - dev_dbg(&client->dev, "write %zu@%d --> %zd (%ld)\n", - count, offset, status, jiffies); - - if (status == count) - return count; - } - - return -ETIMEDOUT; -} - -static ssize_t at24_eeprom_write_smbus_byte(struct at24_data *at24, - const char *buf, - unsigned int offset, size_t count) -{ - unsigned long timeout, write_time; - struct i2c_client *client; - ssize_t status = 0; - - client = at24_translate_offset(at24, &offset); - - loop_until_timeout(timeout, write_time) { - status = i2c_smbus_write_byte_data(client, offset, buf[0]); - if (status == 0) - status = count; - - dev_dbg(&client->dev, "write %zu@%d --> %zd (%ld)\n", - count, offset, status, jiffies); - - if (status == count) - return count; - } - - return -ETIMEDOUT; -} - -static ssize_t at24_eeprom_write_i2c(struct at24_data *at24, const char *buf, - unsigned int offset, size_t count) -{ - unsigned long timeout, write_time; - struct i2c_client *client; - struct i2c_msg msg; - ssize_t status = 0; - int i = 0; + struct regmap *regmap; + int ret; - client = at24_translate_offset(at24, &offset); + at24_client = at24_translate_offset(at24, &offset); + regmap = at24_client->regmap; + client = at24_client->client; count = at24_adjust_write_count(at24, offset, count); - msg.addr = client->addr; - msg.flags = 0; - - /* msg.buf is u8 and casts will mask the values */ - msg.buf = at24->writebuf; - if (at24->chip.flags & AT24_FLAG_ADDR16) - msg.buf[i++] = offset >> 8; - - msg.buf[i++] = offset; - memcpy(&msg.buf[i], buf, count); - msg.len = i + count; - - loop_until_timeout(timeout, write_time) { - status = i2c_transfer(client->adapter, &msg, 1); - if (status == 1) - status = count; - - dev_dbg(&client->dev, "write %zu@%d --> %zd (%ld)\n", - count, offset, status, jiffies); - - if (status == count) + at24_loop_until_timeout(timeout, write_time) { + ret = regmap_bulk_write(regmap, offset, buf, count); + dev_dbg(&client->dev, "write %zu@%d --> %d (%ld)\n", + count, offset, ret, jiffies); + if (!ret) return count; } @@ -562,7 +372,7 @@ static ssize_t at24_eeprom_write_i2c(struct at24_data *at24, const char *buf, static int at24_read(void *priv, unsigned int off, void *val, size_t count) { struct at24_data *at24 = priv; - struct device *dev = &at24->client[0]->dev; + struct device *dev = &at24->client[0].client->dev; char *buf = val; int ret; @@ -587,7 +397,7 @@ static int at24_read(void *priv, unsigned int off, void *val, size_t count) while (count) { int status; - status = at24->read_func(at24, buf, off, count); + status = at24_regmap_read(at24, buf, off, count); if (status < 0) { mutex_unlock(&at24->lock); pm_runtime_put(dev); @@ -608,7 +418,7 @@ static int at24_read(void *priv, unsigned int off, void *val, size_t count) static int at24_write(void *priv, unsigned int off, void *val, size_t count) { struct at24_data *at24 = priv; - struct device *dev = &at24->client[0]->dev; + struct device *dev = &at24->client[0].client->dev; char *buf = val; int ret; @@ -629,12 +439,14 @@ static int at24_write(void *priv, unsigned int off, void *val, size_t count) * from this host, but not from other I2C masters. */ mutex_lock(&at24->lock); + gpiod_set_value_cansleep(at24->wp_gpio, 0); while (count) { int status; - status = at24->write_func(at24, buf, off, count); + status = at24_regmap_write(at24, buf, off, count); if (status < 0) { + gpiod_set_value_cansleep(at24->wp_gpio, 1); mutex_unlock(&at24->lock); pm_runtime_put(dev); return status; @@ -644,6 +456,7 @@ static int at24_write(void *priv, unsigned int off, void *val, size_t count) count -= status; } + gpiod_set_value_cansleep(at24->wp_gpio, 1); mutex_unlock(&at24->lock); pm_runtime_put(dev); @@ -658,6 +471,8 @@ static void at24_get_pdata(struct device *dev, struct at24_platform_data *chip) if (device_property_present(dev, "read-only")) chip->flags |= AT24_FLAG_READONLY; + if (device_property_present(dev, "no-read-rollover")) + chip->flags |= AT24_FLAG_NO_RDROL; err = device_property_read_u32(dev, "size", &val); if (!err) @@ -676,16 +491,38 @@ static void at24_get_pdata(struct device *dev, struct at24_platform_data *chip) } } +static unsigned int at24_get_offset_adj(u8 flags, unsigned int byte_len) +{ + if (flags & AT24_FLAG_MAC) { + /* EUI-48 starts from 0x9a, EUI-64 from 0x98 */ + return 0xa0 - byte_len; + } else if (flags & AT24_FLAG_SERIAL && flags & AT24_FLAG_ADDR16) { + /* + * For 16 bit address pointers, the word address must contain + * a '10' sequence in bits 11 and 10 regardless of the + * intended position of the address pointer. + */ + return 0x0800; + } else if (flags & AT24_FLAG_SERIAL) { + /* + * Otherwise the word address must begin with a '10' sequence, + * regardless of the intended address. + */ + return 0x0080; + } else { + return 0; + } +} + static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) { - struct at24_platform_data chip; - kernel_ulong_t magic = 0; + struct at24_platform_data chip = { 0 }; + const struct at24_chip_data *cd = NULL; bool writable; - int use_smbus = 0; - int use_smbus_write = 0; struct at24_data *at24; int err; - unsigned i, num_addresses; + unsigned int i, num_addresses; + struct regmap_config regmap_config = { }; u8 test_byte; if (client->dev.platform_data) { @@ -698,28 +535,22 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) */ if (client->dev.of_node && of_match_device(at24_of_match, &client->dev)) { - magic = (kernel_ulong_t) - of_device_get_match_data(&client->dev); + cd = of_device_get_match_data(&client->dev); } else if (id) { - magic = id->driver_data; + cd = (void *)id->driver_data; } else { const struct acpi_device_id *aid; aid = acpi_match_device(at24_acpi_ids, &client->dev); if (aid) - magic = aid->driver_data; + cd = (void *)aid->driver_data; } - if (!magic) + if (!cd) return -ENODEV; - chip.byte_len = BIT(magic & AT24_BITMASK(AT24_SIZE_BYTELEN)); - magic >>= AT24_SIZE_BYTELEN; - chip.flags = magic & AT24_BITMASK(AT24_SIZE_FLAGS); - + chip.byte_len = cd->byte_len; + chip.flags = cd->flags; at24_get_pdata(&client->dev, &chip); - - chip.setup = NULL; - chip.context = NULL; } if (!is_power_of_2(chip.byte_len)) @@ -733,43 +564,10 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) dev_warn(&client->dev, "page_size looks suspicious (no power of 2)!\n"); - /* - * REVISIT: the size of the EUI-48 byte array is 6 in at24mac402, while - * the call to ilog2() in AT24_DEVICE_MAGIC() rounds it down to 4. - * - * Eventually we'll get rid of the magic values altoghether in favor of - * real structs, but for now just manually set the right size. - */ - if (chip.flags & AT24_FLAG_MAC && chip.byte_len == 4) - chip.byte_len = 6; - - /* Use I2C operations unless we're stuck with SMBus extensions. */ - if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { - if (chip.flags & AT24_FLAG_ADDR16) - return -EPFNOSUPPORT; - - if (i2c_check_functionality(client->adapter, - I2C_FUNC_SMBUS_READ_I2C_BLOCK)) { - use_smbus = I2C_SMBUS_I2C_BLOCK_DATA; - } else if (i2c_check_functionality(client->adapter, - I2C_FUNC_SMBUS_READ_WORD_DATA)) { - use_smbus = I2C_SMBUS_WORD_DATA; - } else if (i2c_check_functionality(client->adapter, - I2C_FUNC_SMBUS_READ_BYTE_DATA)) { - use_smbus = I2C_SMBUS_BYTE_DATA; - } else { - return -EPFNOSUPPORT; - } - - if (i2c_check_functionality(client->adapter, - I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)) { - use_smbus_write = I2C_SMBUS_I2C_BLOCK_DATA; - } else if (i2c_check_functionality(client->adapter, - I2C_FUNC_SMBUS_WRITE_BYTE_DATA)) { - use_smbus_write = I2C_SMBUS_BYTE_DATA; - chip.page_size = 1; - } - } + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C) && + !i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)) + chip.page_size = 1; if (chip.flags & AT24_FLAG_TAKE8ADDR) num_addresses = 8; @@ -777,16 +575,28 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) num_addresses = DIV_ROUND_UP(chip.byte_len, (chip.flags & AT24_FLAG_ADDR16) ? 65536 : 256); + regmap_config.val_bits = 8; + regmap_config.reg_bits = (chip.flags & AT24_FLAG_ADDR16) ? 16 : 8; + at24 = devm_kzalloc(&client->dev, sizeof(struct at24_data) + - num_addresses * sizeof(struct i2c_client *), GFP_KERNEL); + num_addresses * sizeof(struct at24_client), GFP_KERNEL); if (!at24) return -ENOMEM; mutex_init(&at24->lock); - at24->use_smbus = use_smbus; - at24->use_smbus_write = use_smbus_write; at24->chip = chip; at24->num_addresses = num_addresses; + at24->offset_adj = at24_get_offset_adj(chip.flags, chip.byte_len); + + at24->wp_gpio = devm_gpiod_get_optional(&client->dev, + "wp", GPIOD_OUT_HIGH); + if (IS_ERR(at24->wp_gpio)) + return PTR_ERR(at24->wp_gpio); + + at24->client[0].client = client; + at24->client[0].regmap = devm_regmap_init_i2c(client, ®map_config); + if (IS_ERR(at24->client[0].regmap)) + return PTR_ERR(at24->client[0].regmap); if ((chip.flags & AT24_FLAG_SERIAL) && (chip.flags & AT24_FLAG_MAC)) { dev_err(&client->dev, @@ -794,59 +604,32 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) return -EINVAL; } - if (chip.flags & AT24_FLAG_SERIAL) { - at24->read_func = at24_eeprom_read_serial; - } else if (chip.flags & AT24_FLAG_MAC) { - at24->read_func = at24_eeprom_read_mac; - } else { - at24->read_func = at24->use_smbus ? at24_eeprom_read_smbus - : at24_eeprom_read_i2c; - } - - if (at24->use_smbus) { - if (at24->use_smbus_write == I2C_SMBUS_I2C_BLOCK_DATA) - at24->write_func = at24_eeprom_write_smbus_block; - else - at24->write_func = at24_eeprom_write_smbus_byte; - } else { - at24->write_func = at24_eeprom_write_i2c; - } - writable = !(chip.flags & AT24_FLAG_READONLY); if (writable) { - if (!use_smbus || use_smbus_write) { - - unsigned write_max = chip.page_size; - - if (write_max > io_limit) - write_max = io_limit; - if (use_smbus && write_max > I2C_SMBUS_BLOCK_MAX) - write_max = I2C_SMBUS_BLOCK_MAX; - at24->write_max = write_max; - - /* buffer (data + address at the beginning) */ - at24->writebuf = devm_kzalloc(&client->dev, - write_max + 2, GFP_KERNEL); - if (!at24->writebuf) - return -ENOMEM; - } else { - dev_warn(&client->dev, - "cannot write due to controller restrictions."); - } + at24->write_max = min_t(unsigned int, + chip.page_size, at24_io_limit); + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C) && + at24->write_max > I2C_SMBUS_BLOCK_MAX) + at24->write_max = I2C_SMBUS_BLOCK_MAX; } - at24->client[0] = client; - /* use dummy devices for multiple-address chips */ for (i = 1; i < num_addresses; i++) { - at24->client[i] = i2c_new_dummy(client->adapter, - client->addr + i); - if (!at24->client[i]) { + at24->client[i].client = i2c_new_dummy(client->adapter, + client->addr + i); + if (!at24->client[i].client) { dev_err(&client->dev, "address 0x%02x unavailable\n", client->addr + i); err = -EADDRINUSE; goto err_clients; } + at24->client[i].regmap = devm_regmap_init_i2c( + at24->client[i].client, + ®map_config); + if (IS_ERR(at24->client[i].regmap)) { + err = PTR_ERR(at24->client[i].regmap); + goto err_clients; + } } i2c_set_clientdata(client, at24); @@ -890,12 +673,6 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) dev_info(&client->dev, "%u byte %s EEPROM, %s, %u bytes/write\n", chip.byte_len, client->name, writable ? "writable" : "read-only", at24->write_max); - if (use_smbus == I2C_SMBUS_WORD_DATA || - use_smbus == I2C_SMBUS_BYTE_DATA) { - dev_notice(&client->dev, "Falling back to %s reads, " - "performance will suffer\n", use_smbus == - I2C_SMBUS_WORD_DATA ? "word" : "byte"); - } /* export data to kernel code */ if (chip.setup) @@ -905,8 +682,8 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) err_clients: for (i = 1; i < num_addresses; i++) - if (at24->client[i]) - i2c_unregister_device(at24->client[i]); + if (at24->client[i].client) + i2c_unregister_device(at24->client[i].client); pm_runtime_disable(&client->dev); @@ -923,7 +700,7 @@ static int at24_remove(struct i2c_client *client) nvmem_unregister(at24->nvmem); for (i = 1; i < at24->num_addresses; i++) - i2c_unregister_device(at24->client[i]); + i2c_unregister_device(at24->client[i].client); pm_runtime_disable(&client->dev); pm_runtime_set_suspended(&client->dev); @@ -946,12 +723,12 @@ static struct i2c_driver at24_driver = { static int __init at24_init(void) { - if (!io_limit) { - pr_err("at24: io_limit must not be 0!\n"); + if (!at24_io_limit) { + pr_err("at24: at24_io_limit must not be 0!\n"); return -EINVAL; } - io_limit = rounddown_pow_of_two(io_limit); + at24_io_limit = rounddown_pow_of_two(at24_io_limit); return i2c_add_driver(&at24_driver); } module_init(at24_init); |