usb: Provide usb_speed_string() function

In a few places in the kernel, the code prints
a human-readable USB device speed (eg. "high speed").
This involves a switch statement sometimes wrapped
around in ({ ... }) block leading to code repetition.

To mitigate this issue, this commit introduces
usb_speed_string() function, which returns
a human-readable name of provided speed.

It also changes a few places switch was used to use
this new function.  This changes a bit the way the
speed is printed in few instances at the same time
standardising it.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 17 insertions, 33 deletions

diff --git a/drivers/usb/gadget/langwell_udc.c b/drivers/usb/gadget/langwell_udc.c
index 6e444995d398..c88158f307a8 100644
--- a/drivers/usb/gadget/langwell_udc.c
+++ b/drivers/usb/gadget/langwell_udc.c
@@ -1690,20 +1690,7 @@ static ssize_t show_langwell_udc(struct device *_dev,
                 "BmAttributes: %d\n\n",
                 LPM_PTS(tmp_reg),
                 (tmp_reg & LPM_STS) ? 1 : 0,
-                ({
-                        char    *s;
-                        switch (LPM_PSPD(tmp_reg)) {
-                        case LPM_SPEED_FULL:
-                                s = "Full Speed"; break;
-                        case LPM_SPEED_LOW:
-                                s = "Low Speed"; break;
-                        case LPM_SPEED_HIGH:
-                                s = "High Speed"; break;
-                        default:
-                                s = "Unknown Speed"; break;
-                        }
-                        s;
-                }),
+                usb_speed_string(lpm_device_speed(tmp_reg)),
                 (tmp_reg & LPM_PFSC) ? "Force Full Speed" : "Not Force",
                 (tmp_reg & LPM_PHCD) ? "Disabled" : "Enabled",
                 LPM_BA(tmp_reg));
@@ -2647,12 +2634,24 @@ done:
         dev_vdbg(&dev->pdev->dev, "<--- %s()\n", __func__);
 }
 
+static inline enum usb_device_speed lpm_device_speed(u32 reg)
+{
+        switch (LPM_PSPD(reg)) {
+        case LPM_SPEED_HIGH:
+                return USB_SPEED_HIGH;
+        case LPM_SPEED_FULL:
+                return USB_SPEED_FULL;
+        case LPM_SPEED_LOW:
+                return USB_SPEED_LOW;
+        default:
+                return USB_SPEED_UNKNOWN;
+        }
+}
 
 /* port change detect interrupt handler */
 static void handle_port_change(struct langwell_udc *dev)
 {
         u32     portsc1, devlc;
-        u32     speed;
 
         dev_vdbg(&dev->pdev->dev, "---> %s()\n", __func__);
 
@@ -2667,24 +2666,9 @@ static void handle_port_change(struct langwell_udc *dev)
         /* bus reset is finished */
         if (!(portsc1 & PORTS_PR)) {
                 /* get the speed */
-                speed = LPM_PSPD(devlc);
-                switch (speed) {
-                case LPM_SPEED_HIGH:
-                        dev->gadget.speed = USB_SPEED_HIGH;
-                        break;
-                case LPM_SPEED_FULL:
-                        dev->gadget.speed = USB_SPEED_FULL;
-                        break;
-                case LPM_SPEED_LOW:
-                        dev->gadget.speed = USB_SPEED_LOW;
-                        break;
-                default:
-                        dev->gadget.speed = USB_SPEED_UNKNOWN;
-                        break;
-                }
-                dev_vdbg(&dev->pdev->dev,
-                                "speed = %d, dev->gadget.speed = %d\n",
-                                speed, dev->gadget.speed);
+                dev->gadget.speed = lpm_device_speed(devlc);
+                dev_vdbg(&dev->pdev->dev, "dev->gadget.speed = %d\n",
+                        dev->gadget.speed);
         }
 
         /* LPM L0 to L1 */