[PATCH] USB: Use normal return codes for several routines in hub.c

This patch changes the return codes used by hub_port_wait_reset(),
hub_port_reset(), and hub_port_debounce() in hub.c.  I couldn't stand the
{-1=error, 0=okay, 1=disconnect} scheme; the meanings seemed arbitrary and
I constantly forgot which number stood for what status.  The revised code
uses normal negative error codes, including -ENOTCONN to indicate device
disconnected, or 0 for success.

Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 1505084c5036059d865292ecdd7cb91261243a43..cdade327894b355947b5ca25f3b8c4e13318bca2 100644 (file)
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -876,7 +876,6 @@ static int hub_port_status(struct usb_device *hdev, int port,
 #define HUB_LONG_RESET_TIME    200
 #define HUB_RESET_TIMEOUT      500
 
-/* return: -1 on error, 0 on success, 1 on disconnect.  */
 static int hub_port_wait_reset(struct usb_device *hdev, int port,
                                struct usb_device *udev, unsigned int delay)
 {
@@ -892,17 +891,16 @@ static int hub_port_wait_reset(struct usb_device *hdev, int port,
 
                /* read and decode port status */
                ret = hub_port_status(hdev, port, &portstatus, &portchange);
-               if (ret < 0) {
-                       return -1;
-               }
+               if (ret < 0)
+                       return ret;
 
                /* Device went away? */
                if (!(portstatus & USB_PORT_STAT_CONNECTION))
-                       return 1;
+                       return -ENOTCONN;
 
                /* bomb out completely if something weird happened */
                if ((portchange & USB_PORT_STAT_C_CONNECTION))
-                       return -1;
+                       return -EINVAL;
 
                /* if we`ve finished resetting, then break out of the loop */
                if (!(portstatus & USB_PORT_STAT_RESET) &&
@@ -925,10 +923,9 @@ static int hub_port_wait_reset(struct usb_device *hdev, int port,
                        port + 1, delay);
        }
 
-       return -1;
+       return -EBUSY;
 }
 
-/* return: -1 on error, 0 on success, 1 on disconnect.  */
 static int hub_port_reset(struct usb_device *hdev, int port,
                                struct usb_device *udev, unsigned int delay)
 {
@@ -941,7 +938,7 @@ static int hub_port_reset(struct usb_device *hdev, int port,
 
                /* return on disconnect or reset */
                status = hub_port_wait_reset(hdev, port, udev, delay);
-               if (status != -1) {
+               if (status == -ENOTCONN || status == 0) {
                        clear_port_feature(hdev,
                                port + 1, USB_PORT_FEAT_C_RESET);
                        udev->state = status
@@ -960,7 +957,7 @@ static int hub_port_reset(struct usb_device *hdev, int port,
                "Cannot enable port %i.  Maybe the USB cable is bad?\n",
                port + 1);
 
-       return -1;
+       return status;
 }
 
 static int hub_port_disable(struct usb_device *hdev, int port)
@@ -993,7 +990,6 @@ static int hub_port_disable(struct usb_device *hdev, int port)
 #define HUB_DEBOUNCE_STEP       25
 #define HUB_DEBOUNCE_STABLE      4
 
-/* return: -1 on error, 0 on success, 1 on disconnect.  */
 static int hub_port_debounce(struct usb_device *hdev, int port)
 {
        int ret;
@@ -1008,7 +1004,7 @@ static int hub_port_debounce(struct usb_device *hdev, int port)
 
                ret = hub_port_status(hdev, port, &portstatus, &portchange);
                if (ret < 0)
-                       return -1;
+                       return ret;
 
                if ((portstatus & USB_PORT_STAT_CONNECTION) == connection) {
                        if (connection) {
@@ -1029,7 +1025,7 @@ static int hub_port_debounce(struct usb_device *hdev, int port)
                "debounce: port %d: delay %dms stable %d status 0x%x\n",
                port + 1, delay_time, stable_count, portstatus);
 
-       return ((portstatus&USB_PORT_STAT_CONNECTION)) ? 0 : 1;
+       return (portstatus & USB_PORT_STAT_CONNECTION) ? 0 : -ENOTCONN;
 }
 
 static int hub_set_address(struct usb_device *udev)
@@ -1062,7 +1058,7 @@ hub_port_init (struct usb_device *hdev, struct usb_device *udev, int port)
 {
        static DECLARE_MUTEX(usb_address0_sem);
 
-       int                     i, j, retval = -ENODEV;
+       int                     i, j, retval;
        unsigned                delay = HUB_SHORT_RESET_TIME;
        enum usb_device_speed   oldspeed = udev->speed;
 
@@ -1080,15 +1076,12 @@ hub_port_init (struct usb_device *hdev, struct usb_device *udev, int port)
        down(&usb_address0_sem);
 
        /* Reset the device; full speed may morph to high speed */
-       switch (hub_port_reset(hdev, port, udev, delay)) {
-       case 0:                 /* success, speed is known */
-               break;
-       case 1:                 /* disconnect, give to companion */
-               retval = -EBUSY;
-               /* FALL THROUGH */
-       default:                /* error */
+       retval = hub_port_reset(hdev, port, udev, delay);
+       if (retval < 0)         /* error or disconnect */
                goto fail;
-       }
+                               /* success, speed is known */
+       retval = -ENODEV;
+
        if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
                dev_dbg(&udev->dev, "device reset changed speed!\n");
                goto fail;
@@ -1346,7 +1339,7 @@ static void hub_port_connect_change(struct usb_hub *hub, int port,
                /* reset, set address, get descriptor, add to hub's children */
                down (&udev->serialize);
                status = hub_port_init(hdev, udev, port);
-               if (status == -EBUSY)
+               if (status == -ENOTCONN)
                        break;
                if (status < 0)
                        continue;