usb: dwc3: Add support for USB hibernation in host mode

Add support for hibernation of USB in host mode and
cable disconnected mode by adding proper pm operations
freeze and restore.

Change-Id: Ie1761a8afb0bb44a37d6ed4d046e8a09e1f53c5c
Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org>
Signed-off-by: Ajay Agarwal <ajaya@codeaurora.org>

1 files changed, 85 insertions, 15 deletions

diff --git a/drivers/usb/dwc3/dwc3-msm.c b/drivers/usb/dwc3/dwc3-msm.c
index 3f59a2f8b84f..f94d0ba2f966 100644
--- a/drivers/usb/dwc3/dwc3-msm.c
+++ b/drivers/usb/dwc3/dwc3-msm.c
@@ -1908,6 +1908,18 @@ static void dwc3_msm_power_collapse_por(struct dwc3_msm *mdwc)
 	dwc3_core_init(dwc);
 	/* Re-configure event buffers */
 	dwc3_event_buffers_setup(dwc);
+
+	/* Get initial P3 status and enable IN_P3 event */
+	val = dwc3_msm_read_reg_field(mdwc->base,
+		DWC3_GDBGLTSSM, DWC3_GDBGLTSSM_LINKSTATE_MASK);
+	atomic_set(&mdwc->in_p3, val == DWC3_LINK_STATE_U3);
+	dwc3_msm_write_reg_field(mdwc->base, PWR_EVNT_IRQ_MASK_REG,
+				PWR_EVNT_POWERDOWN_IN_P3_MASK, 1);
+	if (mdwc->otg_state == OTG_STATE_A_HOST) {
+		dev_dbg(mdwc->dev, "%s: set the core in host mode\n",
+							__func__);
+		dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_HOST);
+	}
 }
 
 static int dwc3_msm_prepare_suspend(struct dwc3_msm *mdwc)
@@ -1993,7 +2005,7 @@ static void dwc3_set_phy_speed_flags(struct dwc3_msm *mdwc)
 static void msm_dwc3_perf_vote_update(struct dwc3_msm *mdwc,
 						bool perf_mode);
 
-static int dwc3_msm_suspend(struct dwc3_msm *mdwc)
+static int dwc3_msm_suspend(struct dwc3_msm *mdwc, bool hibernation)
 {
 	int ret, i;
 	struct dwc3 *dwc = platform_get_drvdata(mdwc->dwc3);
@@ -2115,7 +2127,8 @@ static int dwc3_msm_suspend(struct dwc3_msm *mdwc)
 	clk_disable_unprepare(mdwc->xo_clk);
 
 	/* Perform controller power collapse */
-	if (!mdwc->in_host_mode && (!mdwc->vbus_active || mdwc->in_restart)) {
+	if ((!mdwc->in_host_mode && (!mdwc->vbus_active || mdwc->in_restart)) ||
+								hibernation) {
 		mdwc->lpm_flags |= MDWC3_POWER_COLLAPSE;
 		dev_dbg(mdwc->dev, "%s: power collapse\n", __func__);
 		dwc3_msm_config_gdsc(mdwc, 0);
@@ -2254,19 +2267,10 @@ static int dwc3_msm_resume(struct dwc3_msm *mdwc)
 
 	/* Recover from controller power collapse */
 	if (mdwc->lpm_flags & MDWC3_POWER_COLLAPSE) {
-		u32 tmp;
-
 		dev_dbg(mdwc->dev, "%s: exit power collapse\n", __func__);
 
 		dwc3_msm_power_collapse_por(mdwc);
 
-		/* Get initial P3 status and enable IN_P3 event */
-		tmp = dwc3_msm_read_reg_field(mdwc->base,
-			DWC3_GDBGLTSSM, DWC3_GDBGLTSSM_LINKSTATE_MASK);
-		atomic_set(&mdwc->in_p3, tmp == DWC3_LINK_STATE_U3);
-		dwc3_msm_write_reg_field(mdwc->base, PWR_EVNT_IRQ_MASK_REG,
-					PWR_EVNT_POWERDOWN_IN_P3_MASK, 1);
-
 		mdwc->lpm_flags &= ~MDWC3_POWER_COLLAPSE;
 	}
 
@@ -4014,7 +4018,39 @@ static int dwc3_msm_pm_suspend(struct device *dev)
 		return -EBUSY;
 	}
 
-	ret = dwc3_msm_suspend(mdwc);
+	ret = dwc3_msm_suspend(mdwc, false);
+	if (!ret)
+		atomic_set(&mdwc->pm_suspended, 1);
+
+	return ret;
+}
+
+static int dwc3_msm_pm_freeze(struct device *dev)
+{
+	int ret = 0;
+	struct dwc3_msm *mdwc = dev_get_drvdata(dev);
+
+	dev_dbg(dev, "dwc3-msm PM freeze\n");
+	dbg_event(0xFF, "PM Freeze", 0);
+
+	flush_workqueue(mdwc->dwc3_wq);
+
+	/* Resume the core to make sure we can power collapse it */
+	ret = dwc3_msm_resume(mdwc);
+
+	/*
+	 * PHYs also need to be power collapsed, so call the notify_disconnect
+	 * before suspend to ensure it.
+	 */
+	usb_phy_notify_disconnect(mdwc->hs_phy, USB_SPEED_HIGH);
+	if (mdwc->ss_phy->flags & PHY_HOST_MODE) {
+		usb_phy_notify_disconnect(mdwc->ss_phy, USB_SPEED_SUPER);
+		mdwc->ss_phy->flags &= ~PHY_HOST_MODE;
+	}
+
+	mdwc->hs_phy->flags &= ~PHY_HOST_MODE;
+
+	ret = dwc3_msm_suspend(mdwc, true);
 	if (!ret)
 		atomic_set(&mdwc->pm_suspended, 1);
 
@@ -4043,6 +4079,35 @@ static int dwc3_msm_pm_resume(struct device *dev)
 
 	return 0;
 }
+
+static int dwc3_msm_pm_restore(struct device *dev)
+{
+	struct dwc3_msm *mdwc = dev_get_drvdata(dev);
+
+	dev_dbg(dev, "dwc3-msm PM restore\n");
+	dbg_event(0xFF, "PM Restore", 0);
+
+	atomic_set(&mdwc->pm_suspended, 0);
+
+	dwc3_msm_resume(mdwc);
+	pm_runtime_disable(dev);
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+
+	/* Restore PHY flags if hibernated in host mode */
+	if (mdwc->otg_state == OTG_STATE_A_HOST) {
+		mdwc->hs_phy->flags |= PHY_HOST_MODE;
+		if (mdwc->ss_phy) {
+			mdwc->ss_phy->flags |= PHY_HOST_MODE;
+			usb_phy_notify_connect(mdwc->ss_phy,
+						USB_SPEED_SUPER);
+		}
+
+		usb_phy_notify_connect(mdwc->hs_phy, USB_SPEED_HIGH);
+	}
+
+	return 0;
+}
 #endif
 
 #ifdef CONFIG_PM
@@ -4061,7 +4126,7 @@ static int dwc3_msm_runtime_suspend(struct device *dev)
 	dev_dbg(dev, "DWC3-msm runtime suspend\n");
 	dbg_event(0xFF, "RT Sus", 0);
 
-	return dwc3_msm_suspend(mdwc);
+	return dwc3_msm_suspend(mdwc, false);
 }
 
 static int dwc3_msm_runtime_resume(struct device *dev)
@@ -4076,8 +4141,13 @@ static int dwc3_msm_runtime_resume(struct device *dev)
 #endif
 
 static const struct dev_pm_ops dwc3_msm_dev_pm_ops = {
-	.prepare =		dwc3_msm_pm_prepare,
-	SET_SYSTEM_SLEEP_PM_OPS(dwc3_msm_pm_suspend, dwc3_msm_pm_resume)
+	.prepare	= dwc3_msm_pm_prepare,
+	.suspend	= dwc3_msm_pm_suspend,
+	.resume		= dwc3_msm_pm_resume,
+	.freeze		= dwc3_msm_pm_freeze,
+	.thaw		= dwc3_msm_pm_restore,
+	.poweroff	= dwc3_msm_pm_suspend,
+	.restore	= dwc3_msm_pm_restore,
 	SET_RUNTIME_PM_OPS(dwc3_msm_runtime_suspend, dwc3_msm_runtime_resume,
 				dwc3_msm_runtime_idle)
 };