misc: eeprom: at24: register nvmem only after eeprom is ready to use

commit 45df80d7605c25055a85fbc5a8446c81c6c0ca24 upstream.

During nvmem_register() the nvmem core sends notifications when:

    - cell added
    - nvmem added

and during these notifications some callback func may access the nvmem
device, which will fail in case of at24 eeprom because regulator and pm
are enabled after nvmem_register().

Fixes: cd5676db0574 ("misc: eeprom: at24: support pm_runtime control")
Fixes: b20eb4c1f026 ("eeprom: at24: drop unnecessary label")
Cc: stable@vger.kernel.org
Signed-off-by: Vadym Kochan <vadym.kochan@plvision.eu>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
index 9ff18d4961cebc4067d094edf42ce83c235afca6..5561075f7a1bb5ce17402e60cedb56c94a518279 100644 (file)
--- a/drivers/misc/eeprom/at24.c
+++ b/drivers/misc/eeprom/at24.c
@@ -692,10 +692,6 @@ static int at24_probe(struct i2c_client *client)
        nvmem_config.word_size = 1;
        nvmem_config.size = byte_len;
 
-       at24->nvmem = devm_nvmem_register(dev, &nvmem_config);
-       if (IS_ERR(at24->nvmem))
-               return PTR_ERR(at24->nvmem);
-
        i2c_set_clientdata(client, at24);
 
        err = regulator_enable(at24->vcc_reg);
@@ -708,6 +704,13 @@ static int at24_probe(struct i2c_client *client)
        pm_runtime_set_active(dev);
        pm_runtime_enable(dev);
 
+       at24->nvmem = devm_nvmem_register(dev, &nvmem_config);
+       if (IS_ERR(at24->nvmem)) {
+               pm_runtime_disable(dev);
+               regulator_disable(at24->vcc_reg);
+               return PTR_ERR(at24->nvmem);
+       }
+
        /*
         * Perform a one-byte test read to verify that the
         * chip is functional.