From: Gabe Black Date: Thu, 28 Mar 2013 04:32:19 +0000 (+0000) Subject: Exynos: Avoid a divide by zero by specifying a non-zero period for pwm 4 X-Git-Tag: v2013.04-rc3~1^2~76^2~7 X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=34b5ee1f6a7d01560f31be37dca3b2eb62877c50;p=u-boot Exynos: Avoid a divide by zero by specifying a non-zero period for pwm 4 The pwm_config function in the exynos pwm driver divides by its period period parameter. A function was calling pwm_config with a 0ns period and a 0ns duty cycle. That doesn't actually make any sense physically, and results in a divide by zero in the driver. This change changes the parameters to be a 100000ns period and duty cycle. Test with command "sf probe 1:0; time sf read 40008000 0 1000". Try with different numbers of bytes and see that sane values are obtained Build and boot U-boot with this patch, backlight works properly. Signed-off-by: Gabe Black Signed-off-by: Akshay Saraswat Acked-by: Simon Glass Signed-off-by: Minkyu Kang --- diff --git a/arch/arm/cpu/armv7/s5p-common/timer.c b/arch/arm/cpu/armv7/s5p-common/timer.c index de6140516c..6a0fa5862e 100644 --- a/arch/arm/cpu/armv7/s5p-common/timer.c +++ b/arch/arm/cpu/armv7/s5p-common/timer.c @@ -58,7 +58,7 @@ int timer_init(void) { /* PWM Timer 4 */ pwm_init(4, MUX_DIV_4, 0); - pwm_config(4, 0, 0); + pwm_config(4, 100000, 100000); pwm_enable(4); /* Use this as the current monotonic time in us */