pwm: imx-tpm: Enable pinctrl setting for sleep state

Apply the pinctrl setting of sleep state when system enters
suspend state.
Restore to the default pinctrl setting when system resumes.

Signed-off-by: Shenwei Wang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Uwe Kleine-König <[email protected]>

Author: Shenwei Wang

drivers/pwm/pwm-imx-tpm.c

@@ -20,6 +20,7 @@
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/platform_device.h>
 #include <linux/pwm.h>
 #include <linux/slab.h>
@@ -380,6 +381,7 @@ static int pwm_imx_tpm_probe(struct platform_device *pdev)
 static int pwm_imx_tpm_suspend(struct device *dev)
 {
 	struct imx_tpm_pwm_chip *tpm = dev_get_drvdata(dev);
+	int ret;
 
 	if (tpm->enable_count > 0)
 		return -EBUSY;
@@ -393,17 +395,27 @@ static int pwm_imx_tpm_suspend(struct device *dev)
 
 	clk_disable_unprepare(tpm->clk);
 
-	return 0;
+	ret = pinctrl_pm_select_sleep_state(dev);
+	if (ret)
+		clk_prepare_enable(tpm->clk);
+
+	return ret;
 }
 
 static int pwm_imx_tpm_resume(struct device *dev)
 {
 	struct imx_tpm_pwm_chip *tpm = dev_get_drvdata(dev);
 	int ret = 0;
 
-	ret = clk_prepare_enable(tpm->clk);
+	ret = pinctrl_pm_select_default_state(dev);
 	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(tpm->clk);
+	if (ret) {
 		dev_err(dev, "failed to prepare or enable clock: %d\n", ret);
+		pinctrl_pm_select_sleep_state(dev);
+	}
 
 	return ret;
 }