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 paremters 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 gabeblack@google.com Signed-off-by: Akshay Saraswat akshay.s@samsung.com Acked-by: Simon Glass sjg@chromium.org --- Changes since v1: - Added "Acked-by: Simon Glass".
arch/arm/cpu/armv7/s5p-common/timer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm/cpu/armv7/s5p-common/timer.c b/arch/arm/cpu/armv7/s5p-common/timer.c index de61405..6a0fa58 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 */