Add a read only regmap for accessing the EEPROM, and then use that
with the NVMEM framework.
Signed-off-by: Andrew Lunn <andrew@xxxxxxx>
---
drivers/misc/eeprom/at24.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 65 insertions(+)
diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
index 2d3db81be099..0e80c0c09d4e 100644
--- a/drivers/misc/eeprom/at24.c
+++ b/drivers/misc/eeprom/at24.c
@@ -22,6 +22,8 @@
#include <linux/jiffies.h>
#include <linux/of.h>
#include <linux/i2c.h>
+#include <linux/nvmem-provider.h>
+#include <linux/regmap.h>
#include <linux/platform_data/at24.h>
/*
@@ -69,6 +71,10 @@ struct at24_data {
unsigned write_max;
unsigned num_addresses;
+ struct regmap_config regmap_config;
+ struct nvmem_config nvmem_config;
+ struct nvmem_device *nvmem;
+
/*
* Some chips tie up multiple I2C addresses; dummy devices reserve
* them for us, and we'll use them with SMBus calls.
@@ -471,6 +477,34 @@ static ssize_t at24_macc_write(struct memory_accessor *macc, const char *buf,
/*-------------------------------------------------------------------------*/
+/*
+ * Provide a regmap interface, which is registered with the NVMEM
+ * framework
+*/
+static int at24_regmap_read(void *context, const void *reg, size_t reg_size,
+ void *val, size_t val_size)
+{
+ struct at24_data *at24 = context;
+ off_t offset = *(u32 *)reg;
+
+ return at24_read(at24, val, offset, val_size);
+}
+
+static int at24_regmap_write(void *context, const void *data, size_t count)
+{
+ struct at24_data *at24 = context;
+
+ return at24_write(at24, data, 0, count);
+}
+
+static const struct regmap_bus at24_regmap_bus = {
+ .read = at24_regmap_read,
+ .write = at24_regmap_write,
+ .reg_format_endian_default = REGMAP_ENDIAN_NATIVE,
+};
+
+/*-------------------------------------------------------------------------*/
+
#ifdef CONFIG_OF
static void at24_get_ofdata(struct i2c_client *client,
struct at24_platform_data *chip)
@@ -502,6 +536,7 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
int err;
unsigned i, num_addresses;
kernel_ulong_t magic;
+ struct regmap *regmap;
if (client->dev.platform_data) {
chip = *(struct at24_platform_data *)client->dev.platform_data;
@@ -644,6 +679,30 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
if (err)
goto err_clients;
+ at24->regmap_config.reg_bits = 32;
+ at24->regmap_config.val_bits = 8;
+ at24->regmap_config.reg_stride = 1;
+ at24->regmap_config.max_register = at24->bin.size - 1;
+
+ regmap = devm_regmap_init(&client->dev, &at24_regmap_bus, at24,
+ &at24->regmap_config);
+ if (IS_ERR(regmap)) {
+ dev_err(&client->dev, "regmap init failed\n");
+ err = PTR_ERR(regmap);
+ goto err_sysfs;
+ }
+
+ at24->nvmem_config.name = dev_name(&client->dev);
+ at24->nvmem_config.dev = &client->dev;
+ at24->nvmem_config.read_only = !writable;
+ at24->nvmem_config.owner = THIS_MODULE;
+
+ at24->nvmem = nvmem_register(&at24->nvmem_config);
+ if (IS_ERR(at24->nvmem)) {
+ err = PTR_ERR(at24->nvmem);
+ goto err_sysfs;
+ }
+
i2c_set_clientdata(client, at24);
dev_info(&client->dev, "%zu byte %s EEPROM, %s, %u bytes/write\n",
@@ -662,6 +721,9 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
return 0;
+err_sysfs:
+ sysfs_remove_bin_file(&client->dev.kobj, &at24->bin);
+
err_clients:--
for (i = 1; i < num_addresses; i++)
if (at24->client[i])
@@ -676,6 +738,9 @@ static int at24_remove(struct i2c_client *client)
int i;
at24 = i2c_get_clientdata(client);
+
+ nvmem_unregister(at24->nvmem);
+
sysfs_remove_bin_file(&client->dev.kobj, &at24->bin);
for (i = 1; i < at24->num_addresses; i++)