On Mon, Aug 31, 2020 at 3:56 AM Vadym Kochan <vadym.kochan@xxxxxxxxxxx> wrote:
>
> 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().
>
> Signed-off-by: Vadym Kochan <vadym.kochan@xxxxxxxxxxx>
> ---
> v3:
> 1) at24 driver enables regulator and pm state machine after nvmem
> registration which does not allow to use it on handing NVMEM_PRE_ADD event.
>
> drivers/misc/eeprom/at24.c | 11 +++++++----
> 1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
> index 2591c21b2b5d..26a23abc053d 100644
> --- 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.
> --
> 2.17.1
>
Good catch! Thanks for the patch. Can I queue it for fixes
independently from the earlier patches in this series?
Bart
