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path: root/drivers/misc/eeprom/at24.c
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Diffstat (limited to 'drivers/misc/eeprom/at24.c')
-rw-r--r--drivers/misc/eeprom/at24.c731
1 files changed, 254 insertions, 477 deletions
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, &regmap_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,
+ &regmap_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);
generated by cgit (git 2.34.1) at 2024-05-06 18:00:45 +0000