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 <[e-mail]>
Cc: Pavankumar Kondeti <[e-mail]>
Signed-off-by: Felipe Balbi <[e-mail]>

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

···
 	}
 }
 
+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;
···
 
 	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;