i2c: core: Allocate temporary client dynamically

drivers/i2c/i2c-core-base.c: In function ‘i2c_detect.isra’:
drivers/i2c/i2c-core-base.c:2544:1: warning: the frame size of 1312 bytes is larger than 1024 bytes [-Wframe-larger-than=]
 2544 | }
      | ^

Fix this by allocating the temporary client structure dynamically, as it
is a rather large structure (1216 bytes, depending on kernel config).
This is basically a revert of the to-be-fixed commit with some
checkpatch improvements.

Fixes: 735668f8e5c9 ("i2c: core: Allocate temp client on the stack in i2c_detect")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Su Hui <suhui@nfschina.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
[wsa: updated commit message, merged tags from similar patch]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 35a221e2c11c146073be1f24c2ac787910b05cd4..7ad1ad5c8c3f56943b627254b1fdbf8f787afdb5 100644 (file)
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -2506,7 +2506,7 @@ static int i2c_detect_address(struct i2c_client *temp_client,
 static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
 {
        const unsigned short *address_list;
-       struct i2c_client temp_client;
+       struct i2c_client *temp_client;
        int i, err = 0;
 
        address_list = driver->address_list;
@@ -2527,19 +2527,24 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
                return 0;
 
        /* Set up a temporary client to help detect callback */
-       memset(&temp_client, 0, sizeof(temp_client));
-       temp_client.adapter = adapter;
+       temp_client = kzalloc(sizeof(*temp_client), GFP_KERNEL);
+       if (!temp_client)
+               return -ENOMEM;
+
+       temp_client->adapter = adapter;
 
        for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) {
                dev_dbg(&adapter->dev,
                        "found normal entry for adapter %d, addr 0x%02x\n",
                        i2c_adapter_id(adapter), address_list[i]);
-               temp_client.addr = address_list[i];
-               err = i2c_detect_address(&temp_client, driver);
+               temp_client->addr = address_list[i];
+               err = i2c_detect_address(temp_client, driver);
                if (unlikely(err))
                        break;
        }
 
+       kfree(temp_client);
+
        return err;
 }