usb: phy: mxs: Add implementation of set_wakeup

When we need the PHY can be waken up by external signals,
we can call this API. Besides, we call mxs_phy_disconnect_line
at this API to close the connection between USB PHY and
controller, after that, the line state from controller is SE0.
Once the PHY is out of power, without calling mxs_phy_disconnect_line,
there are unknown wakeups due to dp/dm floating at device mode.

Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/phy/phy-mxs-usb.c

@@ -31,6 +31,9 @@
 #define HW_USBPHY_CTRL_SET			0x34
 #define HW_USBPHY_CTRL_CLR			0x38
 
+#define HW_USBPHY_DEBUG_SET			0x54
+#define HW_USBPHY_DEBUG_CLR			0x58
+
 #define HW_USBPHY_IP				0x90
 #define HW_USBPHY_IP_SET			0x94
 #define HW_USBPHY_IP_CLR			0x98
@@ -39,6 +42,9 @@
 #define BM_USBPHY_CTRL_CLKGATE			BIT(30)
 #define BM_USBPHY_CTRL_ENAUTOSET_USBCLKS	BIT(26)
 #define BM_USBPHY_CTRL_ENAUTOCLR_USBCLKGATE	BIT(25)
+#define BM_USBPHY_CTRL_ENVBUSCHG_WKUP		BIT(23)
+#define BM_USBPHY_CTRL_ENIDCHG_WKUP		BIT(22)
+#define BM_USBPHY_CTRL_ENDPDMCHG_WKUP		BIT(21)
 #define BM_USBPHY_CTRL_ENAUTOCLR_PHY_PWD	BIT(20)
 #define BM_USBPHY_CTRL_ENAUTOCLR_CLKGATE	BIT(19)
 #define BM_USBPHY_CTRL_ENAUTO_PWRON_PLL		BIT(18)
@@ -48,6 +54,25 @@
 
 #define BM_USBPHY_IP_FIX                       (BIT(17) | BIT(18))
 
+#define BM_USBPHY_DEBUG_CLKGATE			BIT(30)
+
+/* Anatop Registers */
+#define ANADIG_USB1_VBUS_DET_STAT		0x1c0
+#define ANADIG_USB2_VBUS_DET_STAT		0x220
+
+#define ANADIG_USB1_LOOPBACK_SET		0x1e4
+#define ANADIG_USB1_LOOPBACK_CLR		0x1e8
+#define ANADIG_USB2_LOOPBACK_SET		0x244
+#define ANADIG_USB2_LOOPBACK_CLR		0x248
+
+#define BM_ANADIG_USB1_VBUS_DET_STAT_VBUS_VALID	BIT(3)
+#define BM_ANADIG_USB2_VBUS_DET_STAT_VBUS_VALID	BIT(3)
+
+#define BM_ANADIG_USB1_LOOPBACK_UTMI_DIG_TST1	BIT(2)
+#define BM_ANADIG_USB1_LOOPBACK_TSTI_TX_EN	BIT(5)
+#define BM_ANADIG_USB2_LOOPBACK_UTMI_DIG_TST1	BIT(2)
+#define BM_ANADIG_USB2_LOOPBACK_TSTI_TX_EN	BIT(5)
+
 #define to_mxs_phy(p) container_of((p), struct mxs_phy, phy)
 
 /* Do disconnection between PHY and controller without vbus */
@@ -141,6 +166,79 @@ static int mxs_phy_hw_init(struct mxs_phy *mxs_phy)
 	return 0;
 }
 
+/* Return true if the vbus is there */
+static bool mxs_phy_get_vbus_status(struct mxs_phy *mxs_phy)
+{
+	unsigned int vbus_value;
+
+	if (mxs_phy->port_id == 0)
+		regmap_read(mxs_phy->regmap_anatop,
+			ANADIG_USB1_VBUS_DET_STAT,
+			&vbus_value);
+	else if (mxs_phy->port_id == 1)
+		regmap_read(mxs_phy->regmap_anatop,
+			ANADIG_USB2_VBUS_DET_STAT,
+			&vbus_value);
+
+	if (vbus_value & BM_ANADIG_USB1_VBUS_DET_STAT_VBUS_VALID)
+		return true;
+	else
+		return false;
+}
+
+static void __mxs_phy_disconnect_line(struct mxs_phy *mxs_phy, bool disconnect)
+{
+	void __iomem *base = mxs_phy->phy.io_priv;
+	u32 reg;
+
+	if (disconnect)
+		writel_relaxed(BM_USBPHY_DEBUG_CLKGATE,
+			base + HW_USBPHY_DEBUG_CLR);
+
+	if (mxs_phy->port_id == 0) {
+		reg = disconnect ? ANADIG_USB1_LOOPBACK_SET
+			: ANADIG_USB1_LOOPBACK_CLR;
+		regmap_write(mxs_phy->regmap_anatop, reg,
+			BM_ANADIG_USB1_LOOPBACK_UTMI_DIG_TST1 |
+			BM_ANADIG_USB1_LOOPBACK_TSTI_TX_EN);
+	} else if (mxs_phy->port_id == 1) {
+		reg = disconnect ? ANADIG_USB2_LOOPBACK_SET
+			: ANADIG_USB2_LOOPBACK_CLR;
+		regmap_write(mxs_phy->regmap_anatop, reg,
+			BM_ANADIG_USB2_LOOPBACK_UTMI_DIG_TST1 |
+			BM_ANADIG_USB2_LOOPBACK_TSTI_TX_EN);
+	}
+
+	if (!disconnect)
+		writel_relaxed(BM_USBPHY_DEBUG_CLKGATE,
+			base + HW_USBPHY_DEBUG_SET);
+
+	/* Delay some time, and let Linestate be SE0 for controller */
+	if (disconnect)
+		usleep_range(500, 1000);
+}
+
+static void mxs_phy_disconnect_line(struct mxs_phy *mxs_phy, bool on)
+{
+	bool vbus_is_on = false;
+
+	/* If the SoCs don't need to disconnect line without vbus, quit */
+	if (!(mxs_phy->data->flags & MXS_PHY_DISCONNECT_LINE_WITHOUT_VBUS))
+		return;
+
+	/* If the SoCs don't have anatop, quit */
+	if (!mxs_phy->regmap_anatop)
+		return;
+
+	vbus_is_on = mxs_phy_get_vbus_status(mxs_phy);
+
+	if (on && !vbus_is_on)
+		__mxs_phy_disconnect_line(mxs_phy, true);
+	else
+		__mxs_phy_disconnect_line(mxs_phy, false);
+
+}
+
 static int mxs_phy_init(struct usb_phy *phy)
 {
 	int ret;
@@ -185,6 +283,23 @@ static int mxs_phy_suspend(struct usb_phy *x, int suspend)
 	return 0;
 }
 
+static int mxs_phy_set_wakeup(struct usb_phy *x, bool enabled)
+{
+	struct mxs_phy *mxs_phy = to_mxs_phy(x);
+	u32 value = BM_USBPHY_CTRL_ENVBUSCHG_WKUP |
+			BM_USBPHY_CTRL_ENDPDMCHG_WKUP |
+				BM_USBPHY_CTRL_ENIDCHG_WKUP;
+	if (enabled) {
+		mxs_phy_disconnect_line(mxs_phy, true);
+		writel_relaxed(value, x->io_priv + HW_USBPHY_CTRL_SET);
+	} else {
+		writel_relaxed(value, x->io_priv + HW_USBPHY_CTRL_CLR);
+		mxs_phy_disconnect_line(mxs_phy, false);
+	}
+
+	return 0;
+}
+
 static int mxs_phy_on_connect(struct usb_phy *phy,
 		enum usb_device_speed speed)
 {
@@ -265,6 +380,7 @@ static int mxs_phy_probe(struct platform_device *pdev)
 	mxs_phy->phy.notify_connect	= mxs_phy_on_connect;
 	mxs_phy->phy.notify_disconnect	= mxs_phy_on_disconnect;
 	mxs_phy->phy.type		= USB_PHY_TYPE_USB2;
+	mxs_phy->phy.set_wakeup		= mxs_phy_set_wakeup;
 
 	mxs_phy->clk = clk;
 	mxs_phy->data = of_id->data;