phy: tegra: xusb: Add sleepwalk and suspend/resume

This commit adds sleepwalk/wake and suspend/resume interfaces
to Tegra XUSB PHY driver.

Tegra XUSB host controller driver makes use of sleepwalk functions
to enable/disable sleepwalk circuit which is in always-on partition
and can respond to USB resume signals when controller is not powered.
Sleepwalk can be enabled/disabled for any USB UPHY individually.

  - tegra_xusb_padctl_enable_phy_sleepwalk()
  - tegra_xusb_padctl_disable_phy_sleepwalk()

Tegra XUSB host controller driver makes use of wake functions to
enable/disable/query wake circuit which is in always-on partition
can wake system up when USB resume happens.
Wake circuit can be enabled/disabled for any USB PHY individually.

  - tegra_xusb_padctl_enable_phy_wake()
  - tegra_xusb_padctl_disable_phy_wake()
  - tegra_xusb_padctl_remote_wake_detected()

This commit also adds two system suspend stubs that can be used to
save and restore XUSB PADCTL context during system suspend and
resume.
  - tegra_xusb_padctl_suspend_noirq()
  - tegra_xusb_padctl_resume_noirq()

Signed-off-by: JC Kuo <jckuo@nvidia.com>
Acked-By: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/phy/tegra/xusb.c

@@ -1273,10 +1273,36 @@ static int tegra_xusb_padctl_remove(struct platform_device *pdev)
 	return err;
 }
 
+static int tegra_xusb_padctl_suspend_noirq(struct device *dev)
+{
+	struct tegra_xusb_padctl *padctl = dev_get_drvdata(dev);
+
+	if (padctl->soc && padctl->soc->ops && padctl->soc->ops->suspend_noirq)
+		return padctl->soc->ops->suspend_noirq(padctl);
+
+	return 0;
+}
+
+static int tegra_xusb_padctl_resume_noirq(struct device *dev)
+{
+	struct tegra_xusb_padctl *padctl = dev_get_drvdata(dev);
+
+	if (padctl->soc && padctl->soc->ops && padctl->soc->ops->resume_noirq)
+		return padctl->soc->ops->resume_noirq(padctl);
+
+	return 0;
+}
+
+static const struct dev_pm_ops tegra_xusb_padctl_pm_ops = {
+	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(tegra_xusb_padctl_suspend_noirq,
+				      tegra_xusb_padctl_resume_noirq)
+};
+
 static struct platform_driver tegra_xusb_padctl_driver = {
 	.driver = {
 		.name = "tegra-xusb-padctl",
 		.of_match_table = tegra_xusb_padctl_of_match,
+		.pm = &tegra_xusb_padctl_pm_ops,
 	},
 	.probe = tegra_xusb_padctl_probe,
 	.remove = tegra_xusb_padctl_remove,
@@ -1343,6 +1369,62 @@ int tegra_xusb_padctl_hsic_set_idle(struct tegra_xusb_padctl *padctl,
 }
 EXPORT_SYMBOL_GPL(tegra_xusb_padctl_hsic_set_idle);
 
+int tegra_xusb_padctl_enable_phy_sleepwalk(struct tegra_xusb_padctl *padctl, struct phy *phy,
+					   enum usb_device_speed speed)
+{
+	struct tegra_xusb_lane *lane = phy_get_drvdata(phy);
+
+	if (lane->pad->ops->enable_phy_sleepwalk)
+		return lane->pad->ops->enable_phy_sleepwalk(lane, speed);
+
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL_GPL(tegra_xusb_padctl_enable_phy_sleepwalk);
+
+int tegra_xusb_padctl_disable_phy_sleepwalk(struct tegra_xusb_padctl *padctl, struct phy *phy)
+{
+	struct tegra_xusb_lane *lane = phy_get_drvdata(phy);
+
+	if (lane->pad->ops->disable_phy_sleepwalk)
+		return lane->pad->ops->disable_phy_sleepwalk(lane);
+
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL_GPL(tegra_xusb_padctl_disable_phy_sleepwalk);
+
+int tegra_xusb_padctl_enable_phy_wake(struct tegra_xusb_padctl *padctl, struct phy *phy)
+{
+	struct tegra_xusb_lane *lane = phy_get_drvdata(phy);
+
+	if (lane->pad->ops->enable_phy_wake)
+		return lane->pad->ops->enable_phy_wake(lane);
+
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL_GPL(tegra_xusb_padctl_enable_phy_wake);
+
+int tegra_xusb_padctl_disable_phy_wake(struct tegra_xusb_padctl *padctl, struct phy *phy)
+{
+	struct tegra_xusb_lane *lane = phy_get_drvdata(phy);
+
+	if (lane->pad->ops->disable_phy_wake)
+		return lane->pad->ops->disable_phy_wake(lane);
+
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL_GPL(tegra_xusb_padctl_disable_phy_wake);
+
+bool tegra_xusb_padctl_remote_wake_detected(struct tegra_xusb_padctl *padctl, struct phy *phy)
+{
+	struct tegra_xusb_lane *lane = phy_get_drvdata(phy);
+
+	if (lane->pad->ops->remote_wake_detected)
+		return lane->pad->ops->remote_wake_detected(lane);
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(tegra_xusb_padctl_remote_wake_detected);
+
 int tegra_xusb_padctl_usb3_set_lfps_detect(struct tegra_xusb_padctl *padctl,
 					   unsigned int port, bool enable)
 {

drivers/phy/tegra/xusb.h

@@ -11,6 +11,7 @@
 #include <linux/mutex.h>
 #include <linux/workqueue.h>
 
+#include <linux/usb/ch9.h>
 #include <linux/usb/otg.h>
 #include <linux/usb/role.h>
 
@@ -132,6 +133,11 @@ struct tegra_xusb_lane_ops {
 	void (*remove)(struct tegra_xusb_lane *lane);
 	void (*iddq_enable)(struct tegra_xusb_lane *lane);
 	void (*iddq_disable)(struct tegra_xusb_lane *lane);
+	int (*enable_phy_sleepwalk)(struct tegra_xusb_lane *lane, enum usb_device_speed speed);
+	int (*disable_phy_sleepwalk)(struct tegra_xusb_lane *lane);
+	int (*enable_phy_wake)(struct tegra_xusb_lane *lane);
+	int (*disable_phy_wake)(struct tegra_xusb_lane *lane);
+	bool (*remote_wake_detected)(struct tegra_xusb_lane *lane);
 };
 
 bool tegra_xusb_lane_check(struct tegra_xusb_lane *lane, const char *function);
@@ -396,6 +402,8 @@ struct tegra_xusb_padctl_ops {
 			 const struct tegra_xusb_padctl_soc *soc);
 	void (*remove)(struct tegra_xusb_padctl *padctl);
 
+	int (*suspend_noirq)(struct tegra_xusb_padctl *padctl);
+	int (*resume_noirq)(struct tegra_xusb_padctl *padctl);
 	int (*usb3_save_context)(struct tegra_xusb_padctl *padctl,
 				 unsigned int index);
 	int (*hsic_set_idle)(struct tegra_xusb_padctl *padctl,

include/linux/phy/tegra/xusb.h

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
- * Copyright (c) 2016, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2016-2020, NVIDIA CORPORATION.  All rights reserved.
  */
 
 #ifndef PHY_TEGRA_XUSB_H
@@ -8,6 +8,7 @@
 
 struct tegra_xusb_padctl;
 struct device;
+enum usb_device_speed;
 
 struct tegra_xusb_padctl *tegra_xusb_padctl_get(struct device *dev);
 void tegra_xusb_padctl_put(struct tegra_xusb_padctl *padctl);
@@ -23,4 +24,11 @@ int tegra_xusb_padctl_set_vbus_override(struct tegra_xusb_padctl *padctl,
 int tegra_phy_xusb_utmi_port_reset(struct phy *phy);
 int tegra_xusb_padctl_get_usb3_companion(struct tegra_xusb_padctl *padctl,
 					 unsigned int port);
+int tegra_xusb_padctl_enable_phy_sleepwalk(struct tegra_xusb_padctl *padctl, struct phy *phy,
+					   enum usb_device_speed speed);
+int tegra_xusb_padctl_disable_phy_sleepwalk(struct tegra_xusb_padctl *padctl, struct phy *phy);
+int tegra_xusb_padctl_enable_phy_wake(struct tegra_xusb_padctl *padctl, struct phy *phy);
+int tegra_xusb_padctl_disable_phy_wake(struct tegra_xusb_padctl *padctl, struct phy *phy);
+bool tegra_xusb_padctl_remote_wake_detected(struct tegra_xusb_padctl *padctl, struct phy *phy);
+
 #endif /* PHY_TEGRA_XUSB_H */