[RFC PATCH v1 3/3] usb: phy: mxs: optimize disconnect line condition

[Igor Opaniuk <igor.opaniuk@gmail.com>]

From: Igor Opaniuk <igor.opaniuk@toradex.com>

We only have below cases to disconnect line when suspend:
1. Device mode without connection to any host/charger(no vbus).
2. Device mode connect to a charger, usb suspend when
system is entering suspend.

This patch can fix cases, when usb phy wrongly does disconnect
line in case usb host enters suspend but vbus is off.

Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Igor Opaniuk <igor.opaniuk@toradex.com>
---

 drivers/usb/phy/phy-mxs-usb.c | 28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/drivers/usb/phy/phy-mxs-usb.c b/drivers/usb/phy/phy-mxs-usb.c
index 70b8c8248caf..d996666e09e6 100644
--- a/drivers/usb/phy/phy-mxs-usb.c
+++ b/drivers/usb/phy/phy-mxs-usb.c
@@ -204,6 +204,7 @@ struct mxs_phy {
 	int port_id;
 	u32 tx_reg_set;
 	u32 tx_reg_mask;
+	enum usb_current_mode mode;
 };
 
 static inline bool is_imx6q_phy(struct mxs_phy *mxs_phy)
@@ -386,17 +387,6 @@ static void __mxs_phy_disconnect_line(struct mxs_phy *mxs_phy, bool disconnect)
 		usleep_range(500, 1000);
 }
 
-static bool mxs_phy_is_otg_host(struct mxs_phy *mxs_phy)
-{
-	void __iomem *base = mxs_phy->phy.io_priv;
-	u32 phyctrl = readl(base + HW_USBPHY_CTRL);
-
-	if (IS_ENABLED(CONFIG_USB_OTG) &&
-			!(phyctrl & BM_USBPHY_CTRL_OTG_ID_VALUE))
-		return true;
-
-	return false;
-}
 
 static void mxs_phy_disconnect_line(struct mxs_phy *mxs_phy, bool on)
 {
@@ -412,13 +402,26 @@ static void mxs_phy_disconnect_line(struct mxs_phy *mxs_phy, bool on)
 
 	vbus_is_on = mxs_phy_get_vbus_status(mxs_phy);
 
-	if (on && !vbus_is_on && !mxs_phy_is_otg_host(mxs_phy))
+	if (on && ((!vbus_is_on && mxs_phy->mode != USB_MODE_HOST)))
 		__mxs_phy_disconnect_line(mxs_phy, true);
 	else
 		__mxs_phy_disconnect_line(mxs_phy, false);
 
 }
 
+/*
+ * Set the usb current role for phy.
+ */
+static int mxs_phy_set_mode(struct usb_phy *phy,
+		enum usb_current_mode mode)
+{
+	struct mxs_phy *mxs_phy = to_mxs_phy(phy);
+
+	mxs_phy->mode = mode;
+
+	return 0;
+}
+
 static int mxs_phy_init(struct usb_phy *phy)
 {
 	int ret;
@@ -796,6 +799,7 @@ static int mxs_phy_probe(struct platform_device *pdev)
 	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->phy.set_mode		= mxs_phy_set_mode;
 	mxs_phy->phy.charger_detect	= mxs_phy_charger_detect;
 
 	mxs_phy->clk = clk;
-- 
2.17.1