Re: [PATCH] backlight: adp8860: fix another uninitialized variable use

From: Lee Jones
Date: Mon Jan 11 2016 - 02:57:48 EST


On Mon, 30 Nov 2015, Arnd Bergmann wrote:

> A recent patch I did fixed two potential uses of uninitialized
> variables in the adp8870 and adp8860 drivers. Unfortunately,
> I missed another one:
>
> drivers/video/backlight/adp8860_bl.c: In function 'adp8860_bl_ambient_light_level_show':
> drivers/video/backlight/adp8860_bl.c:570:11: warning: 'reg_val' may be used uninitialized in this function
>
> This does the same change as before in one additional function,
> and also changes the check for the return value in a way that
> avoids another false positive warning with a similar message.
>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> Fixes: 6be3a5a9cd91 ("backlight: adp88x0: Fix uninitialized variable use")
> ---
> Sorry for missing this third hunk the first time around.

Where's your diff?

Applied anyway, thanks.

> diff --git a/drivers/video/backlight/adp8860_bl.c b/drivers/video/backlight/adp8860_bl.c
> index f0d4c0324580..510e559c060e 100644
> --- a/drivers/video/backlight/adp8860_bl.c
> +++ b/drivers/video/backlight/adp8860_bl.c
> @@ -566,11 +566,13 @@ static ssize_t adp8860_bl_ambient_light_level_show(struct device *dev,
>
> mutex_lock(&data->lock);
> error = adp8860_read(data->client, ADP8860_PH1LEVL, &reg_val);
> - ret_val = reg_val;
> - error |= adp8860_read(data->client, ADP8860_PH1LEVH, &reg_val);
> + if (!error) {
> + ret_val = reg_val;
> + error = adp8860_read(data->client, ADP8860_PH1LEVH, &reg_val);
> + }
> mutex_unlock(&data->lock);
>
> - if (error < 0)
> + if (error)
> return error;
>
> /* Return 13-bit conversion value for the first light sensor */
>

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org â Open source software for ARM SoCs
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