Reply-To: <michael.hennerich@analog.com>
Subject: Re: [PATCH] backlight: adp8860: fix another uninitialized variable
 use
References: <3284846.T0rzz6n1As@wuerfel>
To: Arnd Bergmann <arnd@arndb.de>, Lee Jones <lee.jones@linaro.org>
CC: Jingoo Han <jingoohan1@gmail.com>, <linux-fbdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <linux-arm-kernel@lists.infradead.org>
From: Michael Hennerich <michael.hennerich@analog.com>
Organization: Analog Devices Inc.
Message-ID: <565D6937.90503@analog.com>
Date: Tue, 1 Dec 2015 10:32:39 +0100
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On 11/30/2015 12:24 PM, 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@arndb.de>

Acked-by: Michael Hennerich <michael.hennerich@analog.com>

> Fixes: 6be3a5a9cd91 ("backlight: adp88x0: Fix uninitialized variable use")
> ---
> Sorry for missing this third hunk the first time around.
>
> 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 */
>


-- 
Greetings,
Michael

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