eeprom: at24: remove struct at24_client

jira LE-1907
cve CVE-2024-35848
Rebuild_History Non-Buildable kernel-5.14.0-427.31.1.el9_4
commit-author Heiner Kallweit <hkallweit1@gmail.com>
commit 92e1764

We use member client only to get a reference to the associated struct
device, via &client->dev. However we can get the same reference from
the associated regmap, via regmap_get_device(regmap).
Therefore struct at24_client can be removed and replaced with a regmap
pointer.

	Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
	Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
(cherry picked from commit 92e1764)
	Signed-off-by: Jonathan Maple <jmaple@ciq.com>

Author: PlaidCat

drivers/misc/eeprom/at24.c

@@ -68,11 +68,6 @@
  * which won't work on pure SMBus systems.
  */
 
-struct at24_client {
-	struct i2c_client *client;
-	struct regmap *regmap;
-};
-
 struct at24_data {
 	/*
 	 * Lock protects against activities from other Linux tasks,
@@ -94,9 +89,9 @@ struct at24_data {
 
 	/*
 	 * Some chips tie up multiple I2C addresses; dummy devices reserve
-	 * them for us, and we'll use them with SMBus calls.
+	 * them for us.
 	 */
-	struct at24_client client[];
+	struct regmap *client_regmaps[];
 };
 
 /*
@@ -275,8 +270,8 @@ MODULE_DEVICE_TABLE(acpi, at24_acpi_ids);
  * set the byte address; on a multi-master board, another master
  * may have changed the chip's "current" address pointer.
  */
-static struct at24_client *at24_translate_offset(struct at24_data *at24,
-						 unsigned int *offset)
+static struct regmap *at24_translate_offset(struct at24_data *at24,
+					    unsigned int *offset)
 {
 	unsigned int i;
 
@@ -288,12 +283,12 @@ static struct at24_client *at24_translate_offset(struct at24_data *at24,
 		*offset &= 0xff;
 	}
 
-	return &at24->client[i];
+	return at24->client_regmaps[i];
 }
 
 static struct device *at24_base_client_dev(struct at24_data *at24)
 {
-	return &at24->client[0].client->dev;
+	return regmap_get_device(at24->client_regmaps[0]);
 }
 
 static size_t at24_adjust_read_count(struct at24_data *at24,
@@ -324,14 +319,10 @@ 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 regmap *regmap;
 	int ret;
 
-	at24_client = at24_translate_offset(at24, &offset);
-	regmap = at24_client->regmap;
-	client = at24_client->client;
+	regmap = at24_translate_offset(at24, &offset);
 	count = at24_adjust_read_count(at24, offset, count);
 
 	/* adjust offset for mac and serial read ops */
@@ -346,7 +337,7 @@ static ssize_t at24_regmap_read(struct at24_data *at24, char *buf,
 		read_time = jiffies;
 
 		ret = regmap_bulk_read(regmap, offset, buf, count);
-		dev_dbg(&client->dev, "read %zu@%d --> %d (%ld)\n",
+		dev_dbg(regmap_get_device(regmap), "read %zu@%d --> %d (%ld)\n",
 			count, offset, ret, jiffies);
 		if (!ret)
 			return count;
@@ -387,14 +378,10 @@ 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;
+	regmap = at24_translate_offset(at24, &offset);
 	count = at24_adjust_write_count(at24, offset, count);
 	timeout = jiffies + msecs_to_jiffies(at24_write_timeout);
 
@@ -406,7 +393,7 @@ static ssize_t at24_regmap_write(struct at24_data *at24, const char *buf,
 		write_time = jiffies;
 
 		ret = regmap_bulk_write(regmap, offset, buf, count);
-		dev_dbg(&client->dev, "write %zu@%d --> %d (%ld)\n",
+		dev_dbg(regmap_get_device(regmap), "write %zu@%d --> %d (%ld)\n",
 			count, offset, ret, jiffies);
 		if (!ret)
 			return count;
@@ -538,16 +525,14 @@ static const struct at24_chip_data *at24_get_chip_data(struct device *dev)
 }
 
 static int at24_make_dummy_client(struct at24_data *at24, unsigned int index,
+				  struct i2c_client *base_client,
 				  struct regmap_config *regmap_config)
 {
-	struct i2c_client *base_client, *dummy_client;
+	struct i2c_client *dummy_client;
 	struct regmap *regmap;
-	struct device *dev;
-
-	base_client = at24->client[0].client;
-	dev = &base_client->dev;
 
-	dummy_client = devm_i2c_new_dummy_device(dev, base_client->adapter,
+	dummy_client = devm_i2c_new_dummy_device(&base_client->dev,
+						 base_client->adapter,
 						 base_client->addr + index);
 	if (IS_ERR(dummy_client))
 		return PTR_ERR(dummy_client);
@@ -556,8 +541,7 @@ static int at24_make_dummy_client(struct at24_data *at24, unsigned int index,
 	if (IS_ERR(regmap))
 		return PTR_ERR(regmap);
 
-	at24->client[index].client = dummy_client;
-	at24->client[index].regmap = regmap;
+	at24->client_regmaps[index] = regmap;
 
 	return 0;
 }
@@ -680,7 +664,7 @@ static int at24_probe(struct i2c_client *client)
 	if (IS_ERR(regmap))
 		return PTR_ERR(regmap);
 
-	at24 = devm_kzalloc(dev, struct_size(at24, client, num_addresses),
+	at24 = devm_kzalloc(dev, struct_size(at24, client_regmaps, num_addresses),
 			    GFP_KERNEL);
 	if (!at24)
 		return -ENOMEM;
@@ -692,8 +676,7 @@ static int at24_probe(struct i2c_client *client)
 	at24->read_post = cdata->read_post;
 	at24->num_addresses = num_addresses;
 	at24->offset_adj = at24_get_offset_adj(flags, byte_len);
-	at24->client[0].client = client;
-	at24->client[0].regmap = regmap;
+	at24->client_regmaps[0] = regmap;
 
 	at24->vcc_reg = devm_regulator_get(dev, "vcc");
 	if (IS_ERR(at24->vcc_reg))
@@ -709,7 +692,7 @@ static int at24_probe(struct i2c_client *client)
 
 	/* use dummy devices for multiple-address chips */
 	for (i = 1; i < num_addresses; i++) {
-		err = at24_make_dummy_client(at24, i, &regmap_config);
+		err = at24_make_dummy_client(at24, i, client, &regmap_config);
 		if (err)
 			return err;
 	}