[PATCH v1 2/2] usb: cdns3: imx: add power lost support for system resume

Frank Li lznuaa at gmail.com
Thu Feb 18 17:51:09 EST 2021


From: Frank Li <Frank.li at nxp.com>

imx need special handle when controller lost power

Signed-off-by: Peter Chen <peter.chen at nxp.com>
Signed-off-by: Frank Li <Frank.Li at nxp.com>
---
split imx part 

 drivers/usb/cdns3/cdns3-imx.c | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/drivers/usb/cdns3/cdns3-imx.c b/drivers/usb/cdns3/cdns3-imx.c
index 8f88eec0b0ea..708b51cc5844 100644
--- a/drivers/usb/cdns3/cdns3-imx.c
+++ b/drivers/usb/cdns3/cdns3-imx.c
@@ -361,6 +361,39 @@ static int cdns_imx_suspend(struct device *dev)
 
 	return 0;
 }
+
+
+/* Indicate if the controller was power lost before */
+static inline bool cdns_imx_is_power_lost(struct cdns_imx *data)
+{
+	u32 value;
+
+	value = cdns_imx_readl(data, USB3_CORE_CTRL1);
+	if ((value & SW_RESET_MASK) == ALL_SW_RESET)
+		return true;
+	else
+		return false;
+}
+
+static int cdns_imx_system_resume(struct device *dev)
+{
+	struct cdns_imx *data = dev_get_drvdata(dev);
+	int ret;
+
+	ret = cdns_imx_resume(dev);
+	if (ret)
+		return ret;
+
+	if (cdns_imx_is_power_lost(data)) {
+		dev_dbg(dev, "resume from power lost\n");
+		ret = cdns_imx_noncore_init(data);
+		if (ret)
+			cdns_imx_suspend(dev);
+	}
+
+	return ret;
+}
+
 #else
 static int cdns_imx_platform_suspend(struct device *dev,
 	bool suspend, bool wakeup)
@@ -372,6 +405,7 @@ static int cdns_imx_platform_suspend(struct device *dev,
 
 static const struct dev_pm_ops cdns_imx_pm_ops = {
 	SET_RUNTIME_PM_OPS(cdns_imx_suspend, cdns_imx_resume, NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(cdns_imx_suspend, cdns_imx_system_resume)
 };
 
 static const struct of_device_id cdns_imx_of_match[] = {
-- 
2.25.1




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