From c8fa254b77a3238b9e6c489022095556652d353f Mon Sep 17 00:00:00 2001 From: Fancy Fang Date: Fri, 5 May 2023 14:58:39 +0800 Subject: [PATCH] pwm: imx-tpm: force 'real_period' to be zero in suspend MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit [ 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 Signed-off-by: Clark Wang Acked-by: Uwe Kleine-König Fixes: 738a1cfec2ed ("pwm: Add i.MX TPM PWM driver support") Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin --- 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 ed1aad9..318dc0b 100644 --- a/drivers/pwm/pwm-imx-tpm.c +++ b/drivers/pwm/pwm-imx-tpm.c @@ -399,6 +399,13 @@ 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; -- 2.7.4