[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <20230518115258.14320-1-shuijing.li@mediatek.com>
Date: Thu, 18 May 2023 19:52:58 +0800
From: Shuijing Li <shuijing.li@...iatek.com>
To: <thierry.reding@...il.com>, <u.kleine-koenig@...gutronix.de>,
<matthias.bgg@...il.com>, <angelogioacchino.delregno@...labora.com>
CC: <devicetree@...r.kernel.org>, <linux-pwm@...r.kernel.org>,
<linux-kernel@...r.kernel.org>,
<linux-arm-kernel@...ts.infradead.org>,
<linux-mediatek@...ts.infradead.org>,
<Project_Global_Chrome_Upstream_Group@...iatek.com>,
<jitao.shi@...iatek.com>, Shuijing Li <shuijing.li@...iatek.com>
Subject: [PATCH v2] pwm: mtk_disp: Fix the disable flow of disp_pwm
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@...iatek.com>
---
Changes in v2:
Use
if (A && B) {
something();
}
instead of
if (A) {
if (B) {
something();
}
}
per suggestion from the previous thread:
https://lore.kernel.org/lkml/20230515140346.bxeu6xewi6a446nd@pengutronix.de/
---
drivers/pwm/pwm-mtk-disp.c | 13 +++++--------
1 file changed, 5 insertions(+), 8 deletions(-)
diff --git a/drivers/pwm/pwm-mtk-disp.c b/drivers/pwm/pwm-mtk-disp.c
index 79e321e96f56..2401b6733241 100644
--- a/drivers/pwm/pwm-mtk-disp.c
+++ b/drivers/pwm/pwm-mtk-disp.c
@@ -79,14 +79,11 @@ static int mtk_disp_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
if (state->polarity != PWM_POLARITY_NORMAL)
return -EINVAL;
- if (!state->enabled) {
- mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,
- 0x0);
-
- if (mdp->enabled) {
- clk_disable_unprepare(mdp->clk_mm);
- clk_disable_unprepare(mdp->clk_main);
- }
+ if (!state->enabled && 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);
mdp->enabled = false;
return 0;
--
2.40.1
Powered by blists - more mailing lists