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From: iw3gtf@arcor.de
To: barebox@lists.infradead.org
Subject: problem configuring backlight brightness levels in device tree
Date: Mon, 11 Jul 2016 14:24:50 +0200 (CEST)	[thread overview]
Message-ID: <1481832949.59258.1468239890158.JavaMail.ngmail@webmail22.arcor-online.net> (raw)

Hi,

I was trying to configure a pwm backlight on an embedded arm board
and I think I've found a minor problem.

In the source file 'drivers/video/backlight-pwm.c', in the function pwm_backlight_parse_dt()
you set the number of brightness values to:

pwm_backlight->backlight.brightness_max = length / sizeof(u32);

and then loop through the array with:

for (i = 0; i <=  pwm_backlight->backlight.brightness_max; i++)

to find the max of the array.

I think the '<=' should be a '<' otherwise you access an uninitialized value
one past the end of the array; this actually does not directly crash barebox
but the whole brightness values are scaled wrong.

giorgio


Giorgio, iw3gtf@arcor.de

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             reply	other threads:[~2016-07-11 13:00 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-07-11 12:24 iw3gtf [this message]
  -- strict thread matches above, loose matches on Subject: below --
2016-07-11 11:51 giorgio.nicole
2016-07-13  5:18 ` Sascha Hauer

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