usb: phy: msm: Handle disconnect events

Put the transceiver in non-driving mode. Otherwise host
may not detect soft-disconnection.

Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Cc: Pavankumar Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/phy/phy-msm-usb.c

@@ -235,6 +235,23 @@ static void ulpi_init(struct msm_otg *motg)
 	}
 }
 
+static int msm_phy_notify_disconnect(struct usb_phy *phy,
+				   enum usb_device_speed speed)
+{
+	int val;
+
+	/*
+	 * Put the transceiver in non-driving mode. Otherwise host
+	 * may not detect soft-disconnection.
+	 */
+	val = ulpi_read(phy, ULPI_FUNC_CTRL);
+	val &= ~ULPI_FUNC_CTRL_OPMODE_MASK;
+	val |= ULPI_FUNC_CTRL_OPMODE_NONDRIVING;
+	ulpi_write(phy, val, ULPI_FUNC_CTRL);
+
+	return 0;
+}
+
 static int msm_otg_link_clk_reset(struct msm_otg *motg, bool assert)
 {
 	int ret;
@@ -1626,6 +1643,7 @@ static int msm_otg_probe(struct platform_device *pdev)
 
 	phy->init = msm_phy_init;
 	phy->set_power = msm_otg_set_power;
+	phy->notify_disconnect = msm_phy_notify_disconnect;
 
 	phy->io_ops = &msm_otg_io_ops;