From: Fancy Fang <[email protected]>
During suspend, all the tpm registers will lose values.
So the 'real_period' value of struct 'imx_tpm_pwm_chip'
should be forced to be zero to force the period update
code can be executed after system resume back.
Signed-off-by: Fancy Fang <[email protected]>
Signed-off-by: Clark Wang <[email protected]>
---
drivers/pwm/pwm-imx-tpm.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/pwm/pwm-imx-tpm.c b/drivers/pwm/pwm-imx-tpm.c
index 5e2b452ee5f2..98ab65c89685 100644
--- a/drivers/pwm/pwm-imx-tpm.c
+++ b/drivers/pwm/pwm-imx-tpm.c
@@ -397,6 +397,13 @@ static int __maybe_unused pwm_imx_tpm_suspend(struct device *dev)
if (tpm->enable_count > 0)
return -EBUSY;
+ /*
+ * Force 'real_period' to be zero to force period update code
+ * can be executed after system resume back, since suspend causes
+ * the period related registers to become their reset values.
+ */
+ tpm->real_period = 0;
+
clk_disable_unprepare(tpm->clk);
return 0;
--
2.34.1
On Fri, May 05, 2023 at 02:58:39PM +0800, Clark Wang wrote:
> From: Fancy Fang <[email protected]>
>
> During suspend, all the tpm registers will lose values.
> So the 'real_period' value of struct 'imx_tpm_pwm_chip'
> should be forced to be zero to force the period update
> code can be executed after system resume back.
>
> Signed-off-by: Fancy Fang <[email protected]>
> Signed-off-by: Clark Wang <[email protected]>
Acked-by: Uwe Kleine-K?nig <[email protected]>
Fixes: 738a1cfec2ed ("pwm: Add i.MX TPM PWM driver support")
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | https://www.pengutronix.de/ |
On Fri, 05 May 2023 14:58:39 +0800, Clark Wang wrote:
> During suspend, all the tpm registers will lose values.
> So the 'real_period' value of struct 'imx_tpm_pwm_chip'
> should be forced to be zero to force the period update
> code can be executed after system resume back.
>
>
Applied, thanks!
[1/1] pwm: imx-tpm: force 'real_period' to be zero in suspend
commit: 661dfb7f46298e53f6c3deaa772fa527aae86193
Best regards,
--
Thierry Reding <[email protected]>