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.
Fixes: 888a623db5d0 ("pwm: mtk-disp: Implement atomic API .apply()")
Signed-off-by: Shuijing Li <[email protected]>
Reviewed-by: Matthias Brugger <[email protected]>
Tested-by: Fei Shao <[email protected]>
---
Changes in v3:
Add Fixes per suggestion from the previous thread:
https://lore.kernel.org/lkml/CAC=S1nhVrbaAh2u7rG-=-RubsxTZvMBRZO-t0NA8jG7M8187EA@mail.gmail.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/[email protected]/
---
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
Il 31/05/23 05:10, Shuijing Li ha scritto:
> 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.
>
> Fixes: 888a623db5d0 ("pwm: mtk-disp: Implement atomic API .apply()")
> Signed-off-by: Shuijing Li <[email protected]>
> Reviewed-by: Matthias Brugger <[email protected]>
> Tested-by: Fei Shao <[email protected]>
Reviewed-by: AngeloGioacchino Del Regno <[email protected]>
On 31/05/2023 05:10, Shuijing Li wrote:
> 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.
Reviewed-by: Alexandre Mergnat <[email protected]>
--
Regards,
Alexandre
On Wed, May 31, 2023 at 11:10:01AM +0800, Shuijing Li wrote:
> 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.
>
> Fixes: 888a623db5d0 ("pwm: mtk-disp: Implement atomic API .apply()")
> Signed-off-by: Shuijing Li <[email protected]>
> Reviewed-by: Matthias Brugger <[email protected]>
> Tested-by: Fei Shao <[email protected]>
When I sent my ack for v2, I missed there was already a v3, so here
again for the sake of easier maintenance:
Acked-by: Uwe Kleine-K?nig <[email protected]>
> ---
> Changes in v3:
> Add Fixes per suggestion from the previous thread:
Note that for that a new version isn't necessary, patchwork (and I think
also b4) pick up a fixes line from replies.
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | https://www.pengutronix.de/ |
On Wed, 31 May 2023 11:10:01 +0800, Shuijing Li wrote:
> 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.
>
>
Applied, thanks!
[1/1] pwm: mtk_disp: Fix the disable flow of disp_pwm
commit: bc13d60e4e1e945b34769a4a4c2b172e8552abe5
Best regards,
--
Thierry Reding <[email protected]>