[PATCH v2 5/5] mmc: sdhci-esdhc-imx: fix suspend/resume error handling

[ziniu . wang_1]

From: Luke Wang <ziniu.wang_1@xxxxxxx>

Fix several error handling issues in sdhci_esdhc_suspend/resume:

1. Use pm_runtime_resume_and_get() instead of pm_runtime_get_sync()
   to simplify error handling. If it fails, the device is unclocked
   and accessing hardware registers would cause a kernel panic.

2. Make pinctrl_pm_select_sleep_state() and mmc_gpio_set_cd_wake()
   failures non-fatal in suspend path. These failures only mean
   slightly higher power consumption or missing CD wakeup, but should
   not block system suspend.

3. Check pm_runtime_force_resume() return value in resume. If it
   fails (clock enable failure), return immediately since accessing
   hardware registers on an unclocked device would cause a panic.

4. Make mmc_gpio_set_cd_wake(false) call in resume not check return
   value since it always returns 0.

5. Always return 0 on success path instead of propagating non-fatal
   warning return values.

Signed-off-by: Luke Wang <ziniu.wang_1@xxxxxxx>
---
 drivers/mmc/host/sdhci-esdhc-imx.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index c4a22e42628e..4d6818c95809 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -2060,7 +2060,9 @@ static int sdhci_esdhc_suspend(struct device *dev)
 	 * 2, make sure the pm_runtime_force_resume() in sdhci_esdhc_resume() really
 	 *    invoke its ->runtime_resume callback (needs_force_resume = 1).
 	 */
-	pm_runtime_get_sync(dev);
+	ret = pm_runtime_resume_and_get(dev);
+	if (ret)
+		return ret;
 
 	if ((imx_data->socdata->flags & ESDHC_FLAG_STATE_LOST_IN_LPMODE) &&
 		(host->tuning_mode != SDHCI_TUNING_MODE_1)) {
@@ -2094,10 +2096,12 @@ static int sdhci_esdhc_suspend(struct device *dev)
 		 */
 		ret = pinctrl_pm_select_sleep_state(dev);
 		if (ret)
-			return ret;
+			dev_warn(dev, "Failed to select sleep pinctrl state\n");
 	}
 
 	ret = mmc_gpio_set_cd_wake(host->mmc, true);
+	if (ret)
+		dev_warn(dev, "Failed to enable cd wake\n");
 
 	/*
 	 * Make sure invoke runtime_suspend to gate off clock.
@@ -2105,7 +2109,7 @@ static int sdhci_esdhc_suspend(struct device *dev)
 	 */
 	pm_runtime_force_suspend(dev);
 
-	return ret;
+	return 0;
 }
 
 static int sdhci_esdhc_resume(struct device *dev)
@@ -2121,12 +2125,12 @@ static int sdhci_esdhc_resume(struct device *dev)
 			dev_warn(dev, "Failed to restore pinctrl state\n");
 	}
 
-	pm_runtime_force_resume(dev);
-
-	ret = mmc_gpio_set_cd_wake(host->mmc, false);
+	ret = pm_runtime_force_resume(dev);
 	if (ret)
 		return ret;
 
+	mmc_gpio_set_cd_wake(host->mmc, false);
+
 	/* re-initialize hw state in case it's lost in low power mode */
 	sdhci_esdhc_imx_hwinit(host);
 
@@ -2153,7 +2157,7 @@ static int sdhci_esdhc_resume(struct device *dev)
 
 	pm_runtime_put_autosuspend(dev);
 
-	return ret;
+	return 0;
 }
 
 static int sdhci_esdhc_runtime_suspend(struct device *dev)
-- 
2.34.1