[PATCH v18 5/5] usb: dwc3: qcom: Keep power domain on to retain controller status

[Krishna Kurapati <quic_kriskura@quicinc.com>]

From: Sandeep Maheswaram <quic_c_sanm@quicinc.com>

If dwc3 is wakeup capable, keep the power domain always ON so that
wakeup from system suspend can be supported. Otherwise, keep the
power domain ON only during runtime suspend to support wakeup from
runtime suspend.

Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>
---
 drivers/usb/dwc3/dwc3-qcom.c | 28 +++++++++++++++++++++-------
 1 file changed, 21 insertions(+), 7 deletions(-)

diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
index 56ecee0..2f5b5ae 100644
--- a/drivers/usb/dwc3/dwc3-qcom.c
+++ b/drivers/usb/dwc3/dwc3-qcom.c
@@ -17,6 +17,7 @@
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/phy/phy.h>
+#include <linux/pm_domain.h>
 #include <linux/usb/of.h>
 #include <linux/reset.h>
 #include <linux/iopoll.h>
@@ -756,12 +757,13 @@ dwc3_qcom_create_urs_usb_platdev(struct device *dev)
 
 static int dwc3_qcom_probe(struct platform_device *pdev)
 {
-	struct device_node	*np = pdev->dev.of_node;
-	struct device		*dev = &pdev->dev;
-	struct dwc3_qcom	*qcom;
-	struct resource		*res, *parent_res = NULL;
-	int			ret, i;
-	bool			ignore_pipe_clk;
+	struct device_node *np = pdev->dev.of_node;
+	struct device *dev = &pdev->dev;
+	struct dwc3_qcom *qcom;
+	struct resource	*res, *parent_res = NULL;
+	int ret, i;
+	bool ignore_pipe_clk;
+	struct generic_pm_domain *genpd;
 
 	qcom = devm_kzalloc(&pdev->dev, sizeof(*qcom), GFP_KERNEL);
 	if (!qcom)
@@ -770,6 +772,8 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, qcom);
 	qcom->dev = &pdev->dev;
 
+	genpd = pd_to_genpd(qcom->dev->pm_domain);
+
 	if (has_acpi_companion(dev)) {
 		qcom->acpi_pdata = acpi_device_get_match_data(dev);
 		if (!qcom->acpi_pdata) {
@@ -877,7 +881,17 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
 	if (ret)
 		goto interconnect_exit;
 
-	device_init_wakeup(&pdev->dev, 1);
+	if (device_can_wakeup(&qcom->dwc3->dev)) {
+		/*
+		 * Setting GENPD_FLAG_ALWAYS_ON flag takes care of keeping
+		 * GEMPD on in both RT suspend and System suspend cases.
+		 */
+		genpd->flags |= GENPD_FLAG_ALWAYS_ON;
+		device_init_wakeup(&pdev->dev, true);
+	} else {
+		genpd->flags |= GENPD_FLAG_RPM_ALWAYS_ON;
+	}
+
 	qcom->is_suspended = false;
 	pm_runtime_set_active(dev);
 	pm_runtime_enable(dev);
-- 
2.7.4