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

From: Michael Hennerich
Date: Tue Dec 01 2015 - 04:39:05 EST


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@xxxxxxxx>

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

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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