The latest kernel PWM drivers enable the polarity settings. When system run from U-Boot to kerenl, if there are differences in polarity set or duty cycle, the PMW will re-init: close -> set polarity and duty cycle -> enable the PWM. The power supply controled by pwm regulator may have voltage shaking, which lead to the system not stable.
Signed-off-by: Elaine Zhang zhangqing@rock-chips.com Signed-off-by: Kever Yang kever.yang@rock-chips.com Acked-by: Simon Glass sjg@chromium.org ---
Changes in v4: - Split patch into uclass and rockchip patch
Changes in v3: - use bool type for polarity
Changes in v2: - use pwm_set_invert() instead of pwm_set_init() - add comment for polarity
drivers/power/regulator/pwm_regulator.c | 16 ++++++++++++++-- drivers/pwm/pwm-uclass.c | 10 ++++++++++ include/pwm.h | 19 +++++++++++++++++++ 3 files changed, 43 insertions(+), 2 deletions(-)
Applied to u-boot-rockchip/next, thanks!