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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.c131
1 files changed, 129 insertions, 2 deletions
diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
index 764ff5df0dbc..305a7a464d09 100644
--- a/drivers/misc/eeprom/at24.c
+++ b/drivers/misc/eeprom/at24.c
@@ -12,6 +12,7 @@
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
+#include <linux/of_device.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/mutex.h>
@@ -24,6 +25,7 @@
#include <linux/i2c.h>
#include <linux/nvmem-provider.h>
#include <linux/platform_data/at24.h>
+#include <linux/pm_runtime.h>
/*
* I2C EEPROMs from most vendors are inexpensive and mostly interchangeable.
@@ -175,6 +177,64 @@ static const struct i2c_device_id at24_ids[] = {
};
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)
+ },
+ { },
+};
+MODULE_DEVICE_TABLE(of, at24_of_match);
+
static const struct acpi_device_id at24_acpi_ids[] = {
{ "INT3499", AT24_DEVICE_MAGIC(8192 / 8, 0) },
{ }
@@ -365,7 +425,8 @@ static ssize_t at24_eeprom_read_mac(struct at24_data *at24, char *buf,
memset(msg, 0, sizeof(msg));
msg[0].addr = client->addr;
msg[0].buf = addrbuf;
- addrbuf[0] = 0x90 + offset;
+ /* 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;
@@ -501,11 +562,24 @@ 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 i2c_client *client;
char *buf = val;
+ int ret;
if (unlikely(!count))
return count;
+ if (off + count > at24->chip.byte_len)
+ return -EINVAL;
+
+ client = at24_translate_offset(at24, &off);
+
+ ret = pm_runtime_get_sync(&client->dev);
+ if (ret < 0) {
+ pm_runtime_put_noidle(&client->dev);
+ return ret;
+ }
+
/*
* Read data from chip, protecting against concurrent updates
* from this host, but not from other I2C masters.
@@ -518,6 +592,7 @@ static int at24_read(void *priv, unsigned int off, void *val, size_t count)
status = at24->read_func(at24, buf, off, count);
if (status < 0) {
mutex_unlock(&at24->lock);
+ pm_runtime_put(&client->dev);
return status;
}
buf += status;
@@ -527,17 +602,32 @@ static int at24_read(void *priv, unsigned int off, void *val, size_t count)
mutex_unlock(&at24->lock);
+ pm_runtime_put(&client->dev);
+
return 0;
}
static int at24_write(void *priv, unsigned int off, void *val, size_t count)
{
struct at24_data *at24 = priv;
+ struct i2c_client *client;
char *buf = val;
+ int ret;
if (unlikely(!count))
return -EINVAL;
+ if (off + count > at24->chip.byte_len)
+ return -EINVAL;
+
+ client = at24_translate_offset(at24, &off);
+
+ ret = pm_runtime_get_sync(&client->dev);
+ if (ret < 0) {
+ pm_runtime_put_noidle(&client->dev);
+ return ret;
+ }
+
/*
* Write data to chip, protecting against concurrent updates
* from this host, but not from other I2C masters.
@@ -550,6 +640,7 @@ static int at24_write(void *priv, unsigned int off, void *val, size_t count)
status = at24->write_func(at24, buf, off, count);
if (status < 0) {
mutex_unlock(&at24->lock);
+ pm_runtime_put(&client->dev);
return status;
}
buf += status;
@@ -559,6 +650,8 @@ static int at24_write(void *priv, unsigned int off, void *val, size_t count)
mutex_unlock(&at24->lock);
+ pm_runtime_put(&client->dev);
+
return 0;
}
@@ -570,6 +663,10 @@ 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;
+ err = device_property_read_u32(dev, "size", &val);
+ if (!err)
+ chip->byte_len = val;
+
err = device_property_read_u32(dev, "pagesize", &val);
if (!err) {
chip->page_size = val;
@@ -598,7 +695,16 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
if (client->dev.platform_data) {
chip = *(struct at24_platform_data *)client->dev.platform_data;
} else {
- if (id) {
+ /*
+ * The I2C core allows OF nodes compatibles to match against the
+ * I2C device ID table as a fallback, so check not only if an OF
+ * node is present but also if it matches an OF device ID entry.
+ */
+ if (client->dev.of_node &&
+ of_match_device(at24_of_match, &client->dev)) {
+ magic = (kernel_ulong_t)
+ of_device_get_match_data(&client->dev);
+ } else if (id) {
magic = id->driver_data;
} else {
const struct acpi_device_id *aid;
@@ -631,6 +737,16 @@ 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)
@@ -739,11 +855,16 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
i2c_set_clientdata(client, at24);
+ /* enable runtime pm */
+ pm_runtime_set_active(&client->dev);
+ pm_runtime_enable(&client->dev);
+
/*
* Perform a one-byte test read to verify that the
* chip is functional.
*/
err = at24_read(at24, 0, &test_byte, 1);
+ pm_runtime_idle(&client->dev);
if (err) {
err = -ENODEV;
goto err_clients;
@@ -791,6 +912,8 @@ err_clients:
if (at24->client[i])
i2c_unregister_device(at24->client[i]);
+ pm_runtime_disable(&client->dev);
+
return err;
}
@@ -806,6 +929,9 @@ static int at24_remove(struct i2c_client *client)
for (i = 1; i < at24->num_addresses; i++)
i2c_unregister_device(at24->client[i]);
+ pm_runtime_disable(&client->dev);
+ pm_runtime_set_suspended(&client->dev);
+
return 0;
}
@@ -814,6 +940,7 @@ static int at24_remove(struct i2c_client *client)
static struct i2c_driver at24_driver = {
.driver = {
.name = "at24",
+ .of_match_table = at24_of_match,
.acpi_match_table = ACPI_PTR(at24_acpi_ids),
},
.probe = at24_probe,
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-24 18:25:42 +0300