usb: misc: usb3503: Actively manage Hub Connect GPIO

If the connect signal is pulled high then the device will start up meaning
that if we just pull it high on probe then the device will start running
prior to the configuration being written out. Fix this by pulling the GPIO
low when we reset and only pulling it high when configuration is finished.

Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/misc/usb3503.c

@@ -100,10 +100,13 @@ static int usb3503_clear_bits(struct i2c_client *client, char reg, char req)
 	return 0;
 }
 
-static int usb3503_reset(int gpio_reset, int state)
+static int usb3503_reset(struct usb3503 *hub, int state)
 {
-	if (gpio_is_valid(gpio_reset))
-		gpio_set_value_cansleep(gpio_reset, state);
+	if (!state && gpio_is_valid(hub->gpio_connect))
+		gpio_set_value_cansleep(hub->gpio_connect, 0);
+
+	if (gpio_is_valid(hub->gpio_reset))
+		gpio_set_value_cansleep(hub->gpio_reset, state);
 
 	/* Wait T_HUBINIT == 4ms for hub logic to stabilize */
 	if (state)
@@ -119,7 +122,7 @@ static int usb3503_switch_mode(struct usb3503 *hub, enum usb3503_mode mode)
 
 	switch (mode) {
 	case USB3503_MODE_HUB:
-		usb3503_reset(hub->gpio_reset, 1);
+		usb3503_reset(hub, 1);
 
 		/* SP_ILOCK: set connect_n, config_n for config */
 		err = usb3503_write_register(i2c, USB3503_SP_ILOCK,
@@ -156,12 +159,15 @@ static int usb3503_switch_mode(struct usb3503 *hub, enum usb3503_mode mode)
 			goto err_hubmode;
 		}
 
+		if (gpio_is_valid(hub->gpio_connect))
+			gpio_set_value_cansleep(hub->gpio_connect, 1);
+
 		hub->mode = mode;
 		dev_info(&i2c->dev, "switched to HUB mode\n");
 		break;
 
 	case USB3503_MODE_STANDBY:
-		usb3503_reset(hub->gpio_reset, 0);
+		usb3503_reset(hub, 0);
 
 		hub->mode = mode;
 		dev_info(&i2c->dev, "switched to STANDBY mode\n");
@@ -241,7 +247,7 @@ static int usb3503_probe(struct i2c_client *i2c, const struct i2c_device_id *id)
 
 	if (gpio_is_valid(hub->gpio_connect)) {
 		err = devm_gpio_request_one(&i2c->dev, hub->gpio_connect,
-				GPIOF_OUT_INIT_HIGH, "usb3503 connect");
+				GPIOF_OUT_INIT_LOW, "usb3503 connect");
 		if (err) {
 			dev_err(&i2c->dev,
 					"unable to request GPIO %d as connect pin (%d)\n",