[PATCH] pwm: mtk_disp: Fix the disable flow of disp_pwm

Shuijing Li shuijing.li at mediatek.com
Sun May 14 23:18:45 PDT 2023


There is a flow error in the original mtk_disp_pwm_apply() function.
If this function is called when the clock is disabled, there will be a
chance to operate the disp_pwm register, resulting in disp_pwm exception.
Fix this accordingly.

Signed-off-by: Shuijing Li <shuijing.li at mediatek.com>
---
 drivers/pwm/pwm-mtk-disp.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/pwm/pwm-mtk-disp.c b/drivers/pwm/pwm-mtk-disp.c
index 79e321e96f56..cb699fa9a5ae 100644
--- a/drivers/pwm/pwm-mtk-disp.c
+++ b/drivers/pwm/pwm-mtk-disp.c
@@ -80,10 +80,9 @@ static int mtk_disp_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 		return -EINVAL;
 
 	if (!state->enabled) {
-		mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,
-					 0x0);
-
 		if (mdp->enabled) {
+			mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN,
+						 mdp->data->enable_mask, 0x0);
 			clk_disable_unprepare(mdp->clk_mm);
 			clk_disable_unprepare(mdp->clk_main);
 		}
-- 
2.40.1




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