From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexandre Courbot Date: Mon, 09 Jul 2012 06:04:23 +0000 Subject: [PATCHv3] pwm_backlight: pass correct brightness to callback Message-Id: <1341813863-18822-1-git-send-email-acourbot@nvidia.com> List-Id: References: <4FFA6BCA.2040101@nvidia.com> In-Reply-To: <4FFA6BCA.2040101@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Thierry Reding Cc: linux-kernel@vger.kernel.org, linux-fbdev@vger.kernel.org, Alexandre Courbot pwm_backlight_update_status calls the notify() and notify_after() callbacks before and after applying the new PWM settings. However, if brightness levels are used, the brightness value will be changed from the index into the levels array to the PWM duty cycle length before being passed to notify_after(), which results in inconsistent behavior. Signed-off-by: Alexandre Courbot --- drivers/video/backlight/pwm_bl.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index 057389d..be48517 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -54,14 +54,17 @@ static int pwm_backlight_update_status(struct backlight_device *bl) pwm_config(pb->pwm, 0, pb->period); pwm_disable(pb->pwm); } else { + int duty_cycle; if (pb->levels) { - brightness = pb->levels[brightness]; + duty_cycle = pb->levels[brightness]; max = pb->levels[max]; + } else { + duty_cycle = brightness; } - brightness = pb->lth_brightness + - (brightness * (pb->period - pb->lth_brightness) / max); - pwm_config(pb->pwm, brightness, pb->period); + duty_cycle = pb->lth_brightness + + (duty_cycle * (pb->period - pb->lth_brightness) / max); + pwm_config(pb->pwm, duty_cycle, pb->period); pwm_enable(pb->pwm); } -- 1.7.11.1