eeprom: at24: add regmap-based write function

Add a regmap-based write function.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

drivers/misc/eeprom/at24.c

@@ -538,6 +538,31 @@ static ssize_t at24_eeprom_write_smbus_byte(struct at24_data *at24,
 	return -ETIMEDOUT;
 }
 
+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;
+	struct regmap *regmap;
+	int ret;
+
+	at24_client = at24_translate_offset(at24, &offset);
+	regmap = at24_client->regmap;
+	client = at24_client->client;
+	count = at24_adjust_write_count(at24, offset, count);
+
+	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;
+	}
+
+	return -ETIMEDOUT;
+}
+
 static ssize_t at24_eeprom_write_i2c(struct at24_data *at24, const char *buf,
 				     unsigned int offset, size_t count)
 {
@@ -653,7 +678,7 @@ static int at24_write(void *priv, unsigned int off, void *val, size_t count)
 	while (count) {
 		int status;
 
-		status = at24->write_func(at24, buf, off, count);
+		status = at24_regmap_write(at24, buf, off, count);
 		if (status < 0) {
 			mutex_unlock(&at24->lock);
 			pm_runtime_put(dev);