From: Fancy Fang <chen.fang@xxxxxxx>
[ Upstream commit 661dfb7f46298e53f6c3deaa772fa527aae86193 ]
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 <chen.fang@xxxxxxx>
Signed-off-by: Clark Wang <xiaoning.wang@xxxxxxx>
Acked-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
Fixes: 738a1cfec2ed ("pwm: Add i.MX TPM PWM driver support")
Signed-off-by: Thierry Reding <thierry.reding@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 fcdf6befb8389..871527b78aa46 100644
--- a/drivers/pwm/pwm-imx-tpm.c
+++ b/drivers/pwm/pwm-imx-tpm.c
@@ -403,6 +403,13 @@ 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;
--
2.39.2
