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authorMichal Nazarewicz <mina86@mina86.com>2011-08-30 17:11:19 +0200
committerGreg Kroah-Hartman <gregkh@suse.de>2011-09-18 01:29:04 -0700
commite538dfdae85244fd2c4231725d82cc1f1bc4942c (patch)
treef8471dd9af305b95557d29a30f427c85418b1621
parentc58a76cdd7ab5a945a44fd2d64f6faf40323f95b (diff)
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>
-rw-r--r--drivers/usb/Kconfig5
-rw-r--r--drivers/usb/Makefile2
-rw-r--r--drivers/usb/core/hub.c27
-rw-r--r--drivers/usb/gadget/amd5536udc.c9
-rw-r--r--drivers/usb/gadget/atmel_usba_udc.c9
-rw-r--r--drivers/usb/gadget/composite.c22
-rw-r--r--drivers/usb/gadget/file_storage.c15
-rw-r--r--drivers/usb/gadget/fsl_udc_core.c53
-rw-r--r--drivers/usb/gadget/gmidi.c11
-rw-r--r--drivers/usb/gadget/langwell_udc.c50
-rw-r--r--drivers/usb/gadget/net2272.c4
-rw-r--r--drivers/usb/gadget/net2280.c4
-rw-r--r--drivers/usb/gadget/printer.c14
-rw-r--r--drivers/usb/gadget/s3c-hsotg.c8
-rw-r--r--drivers/usb/gadget/udc-core.c19
-rw-r--r--drivers/usb/misc/usbtest.c21
-rw-r--r--drivers/usb/usb-common.c35
-rw-r--r--include/linux/usb/ch9.h12
18 files changed, 125 insertions, 195 deletions
diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig
index 2651852952be..97c4cc724189 100644
--- a/drivers/usb/Kconfig
+++ b/drivers/usb/Kconfig
@@ -12,6 +12,11 @@ menuconfig USB_SUPPORT
if USB_SUPPORT
+config USB_COMMON
+ tristate
+ default y
+ depends on USB || USB_GADGET
+
# Host-side USB depends on having a host controller
# NOTE: dummy_hcd is always an option, but it's ignored here ...
# NOTE: SL-811 option should be board-specific ...
diff --git a/drivers/usb/Makefile b/drivers/usb/Makefile
index 969b0a50bc98..75eca7645227 100644
--- a/drivers/usb/Makefile
+++ b/drivers/usb/Makefile
@@ -53,3 +53,5 @@ obj-$(CONFIG_USB_MUSB_HDRC) += musb/
obj-$(CONFIG_USB_RENESAS_USBHS) += renesas_usbhs/
obj-$(CONFIG_USB_OTG_UTILS) += otg/
obj-$(CONFIG_USB_GADGET) += gadget/
+
+obj-$(CONFIG_USB_COMMON) += usb-common.o
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 338f91ff54cb..3edc01bc41f7 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -2793,7 +2793,7 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
int i, j, retval;
unsigned delay = HUB_SHORT_RESET_TIME;
enum usb_device_speed oldspeed = udev->speed;
- char *speed, *type;
+ const char *speed;
int devnum = udev->devnum;
/* root hub ports have a slightly longer reset period
@@ -2853,25 +2853,16 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
default:
goto fail;
}
-
- type = "";
- switch (udev->speed) {
- case USB_SPEED_LOW: speed = "low"; break;
- case USB_SPEED_FULL: speed = "full"; break;
- case USB_SPEED_HIGH: speed = "high"; break;
- case USB_SPEED_SUPER:
- speed = "super";
- break;
- case USB_SPEED_WIRELESS:
- speed = "variable";
- type = "Wireless ";
- break;
- default: speed = "?"; break;
- }
+
+ if (udev->speed == USB_SPEED_WIRELESS)
+ speed = "variable speed Wireless";
+ else
+ speed = usb_speed_string(udev->speed);
+
if (udev->speed != USB_SPEED_SUPER)
dev_info(&udev->dev,
- "%s %s speed %sUSB device number %d using %s\n",
- (udev->config) ? "reset" : "new", speed, type,
+ "%s %s USB device number %d using %s\n",
+ (udev->config) ? "reset" : "new", speed,
devnum, udev->bus->controller->driver->name);
/* Set up TT records, if needed */
diff --git a/drivers/usb/gadget/amd5536udc.c b/drivers/usb/gadget/amd5536udc.c
index ded8d6fddb53..4730016d7cd4 100644
--- a/drivers/usb/gadget/amd5536udc.c
+++ b/drivers/usb/gadget/amd5536udc.c
@@ -3005,13 +3005,8 @@ __acquires(dev->lock)
/* link up all endpoints */
udc_setup_endpoints(dev);
- if (dev->gadget.speed == USB_SPEED_HIGH) {
- dev_info(&dev->pdev->dev, "Connect: speed = %s\n",
- "high");
- } else if (dev->gadget.speed == USB_SPEED_FULL) {
- dev_info(&dev->pdev->dev, "Connect: speed = %s\n",
- "full");
- }
+ dev_info(&dev->pdev->dev, "Connect: %s\n",
+ usb_speed_string(dev->gadget.speed));
/* init ep 0 */
activate_control_endpoints(dev);
diff --git a/drivers/usb/gadget/atmel_usba_udc.c b/drivers/usb/gadget/atmel_usba_udc.c
index 722c468e9b3c..271a9d873608 100644
--- a/drivers/usb/gadget/atmel_usba_udc.c
+++ b/drivers/usb/gadget/atmel_usba_udc.c
@@ -1718,13 +1718,12 @@ static irqreturn_t usba_udc_irq(int irq, void *devid)
spin_lock(&udc->lock);
}
- if (status & USBA_HIGH_SPEED) {
- DBG(DBG_BUS, "High-speed bus reset detected\n");
+ if (status & USBA_HIGH_SPEED)
udc->gadget.speed = USB_SPEED_HIGH;
- } else {
- DBG(DBG_BUS, "Full-speed bus reset detected\n");
+ else
udc->gadget.speed = USB_SPEED_FULL;
- }
+ DBG(DBG_BUS, "%s bus reset detected\n",
+ usb_speed_string(udc->gadget.speed));
ep0 = &usba_ep[0];
ep0->desc = &usba_ep0_desc;
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index c77aca11ad53..e74fd55c33d9 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -617,25 +617,9 @@ static int set_config(struct usb_composite_dev *cdev,
result = 0;
}
- INFO(cdev, "%s speed config #%d: %s\n",
- ({ char *speed;
- switch (gadget->speed) {
- case USB_SPEED_LOW:
- speed = "low";
- break;
- case USB_SPEED_FULL:
- speed = "full";
- break;
- case USB_SPEED_HIGH:
- speed = "high";
- break;
- case USB_SPEED_SUPER:
- speed = "super";
- break;
- default:
- speed = "?";
- break;
- } ; speed; }), number, c ? c->label : "unconfigured");
+ INFO(cdev, "%s config #%d: %s\n",
+ usb_speed_string(gadget->speed),
+ number, c ? c->label : "unconfigured");
if (!c)
goto done;
diff --git a/drivers/usb/gadget/file_storage.c b/drivers/usb/gadget/file_storage.c
index 39ece40a045f..4ac8084b579c 100644
--- a/drivers/usb/gadget/file_storage.c
+++ b/drivers/usb/gadget/file_storage.c
@@ -2862,17 +2862,10 @@ static int do_set_config(struct fsg_dev *fsg, u8 new_config)
fsg->config = new_config;
if ((rc = do_set_interface(fsg, 0)) != 0)
fsg->config = 0; // Reset on errors
- else {
- char *speed;
-
- switch (fsg->gadget->speed) {
- case USB_SPEED_LOW: speed = "low"; break;
- case USB_SPEED_FULL: speed = "full"; break;
- case USB_SPEED_HIGH: speed = "high"; break;
- default: speed = "?"; break;
- }
- INFO(fsg, "%s speed config #%d\n", speed, fsg->config);
- }
+ else
+ INFO(fsg, "%s config #%d\n",
+ usb_speed_string(fsg->gadget->speed),
+ fsg->config);
}
return rc;
}
diff --git a/drivers/usb/gadget/fsl_udc_core.c b/drivers/usb/gadget/fsl_udc_core.c
index d6993507165b..b2c44e1d5813 100644
--- a/drivers/usb/gadget/fsl_udc_core.c
+++ b/drivers/usb/gadget/fsl_udc_core.c
@@ -1715,34 +1715,31 @@ static void dtd_complete_irq(struct fsl_udc *udc)
}
}
+static inline enum usb_device_speed portscx_device_speed(u32 reg)
+{
+ switch (speed & PORTSCX_PORT_SPEED_MASK) {
+ case PORTSCX_PORT_SPEED_HIGH:
+ return USB_SPEED_HIGH;
+ case PORTSCX_PORT_SPEED_FULL:
+ return USB_SPEED_FULL;
+ case PORTSCX_PORT_SPEED_LOW:
+ return USB_SPEED_LOW;
+ default:
+ return USB_SPEED_UNKNOWN;
+ }
+}
+
/* Process a port change interrupt */
static void port_change_irq(struct fsl_udc *udc)
{
- u32 speed;
-
if (udc->bus_reset)
udc->bus_reset = 0;
/* Bus resetting is finished */
- if (!(fsl_readl(&dr_regs->portsc1) & PORTSCX_PORT_RESET)) {
+ if (!(fsl_readl(&dr_regs->portsc1) & PORTSCX_PORT_RESET))
/* Get the speed */
- speed = (fsl_readl(&dr_regs->portsc1)
- & PORTSCX_PORT_SPEED_MASK);
- switch (speed) {
- case PORTSCX_PORT_SPEED_HIGH:
- udc->gadget.speed = USB_SPEED_HIGH;
- break;
- case PORTSCX_PORT_SPEED_FULL:
- udc->gadget.speed = USB_SPEED_FULL;
- break;
- case PORTSCX_PORT_SPEED_LOW:
- udc->gadget.speed = USB_SPEED_LOW;
- break;
- default:
- udc->gadget.speed = USB_SPEED_UNKNOWN;
- break;
- }
- }
+ udc->gadget.speed =
+ portscx_device_speed(fsl_readl(&dr_regs->portsc1));
/* Update USB state */
if (!udc->resume_state)
@@ -2167,20 +2164,8 @@ static int fsl_proc_read(char *page, char **start, off_t off, int count,
default:
s = "None"; break;
}
- s;} ), ( {
- char *s;
- switch (tmp_reg & PORTSCX_PORT_SPEED_UNDEF) {
- case PORTSCX_PORT_SPEED_FULL:
- s = "Full Speed"; break;
- case PORTSCX_PORT_SPEED_LOW:
- s = "Low Speed"; break;
- case PORTSCX_PORT_SPEED_HIGH:
- s = "High Speed"; break;
- default:
- s = "Undefined"; break;
- }
- s;
- } ),
+ s;} ),
+ usb_speed_string(portscx_device_speed(tmp_reg)),
(tmp_reg & PORTSCX_PHY_LOW_POWER_SPD) ?
"Normal PHY mode" : "Low power mode",
(tmp_reg & PORTSCX_PORT_RESET) ? "In Reset" :
diff --git a/drivers/usb/gadget/gmidi.c b/drivers/usb/gadget/gmidi.c
index 8b9220e128a7..893b967b0aff 100644
--- a/drivers/usb/gadget/gmidi.c
+++ b/drivers/usb/gadget/gmidi.c
@@ -640,17 +640,8 @@ gmidi_set_config(struct gmidi_device *dev, unsigned number, gfp_t gfp_flags)
if (result) {
gmidi_reset_config(dev);
} else {
- char *speed;
-
- switch (gadget->speed) {
- case USB_SPEED_LOW: speed = "low"; break;
- case USB_SPEED_FULL: speed = "full"; break;
- case USB_SPEED_HIGH: speed = "high"; break;
- default: speed = "?"; break;
- }
-
dev->config = number;
- INFO(dev, "%s speed\n", speed);
+ INFO(dev, "%s speed\n", usb_speed_string(gadget->speed));
}
return result;
}
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 */
diff --git a/drivers/usb/gadget/net2272.c b/drivers/usb/gadget/net2272.c
index 6fef1c02448e..08a4a36550d2 100644
--- a/drivers/usb/gadget/net2272.c
+++ b/drivers/usb/gadget/net2272.c
@@ -1764,8 +1764,8 @@ net2272_handle_stat0_irqs(struct net2272 *dev, u8 stat)
dev->gadget.speed = USB_SPEED_HIGH;
else
dev->gadget.speed = USB_SPEED_FULL;
- dev_dbg(dev->dev, "%s speed\n",
- (dev->gadget.speed == USB_SPEED_HIGH) ? "high" : "full");
+ dev_dbg(dev->dev, "%s\n",
+ usb_speed_string(dev->gadget.speed));
}
ep = &dev->ep[0];
diff --git a/drivers/usb/gadget/net2280.c b/drivers/usb/gadget/net2280.c
index 3c14c4ea8efd..db508d0bb3af 100644
--- a/drivers/usb/gadget/net2280.c
+++ b/drivers/usb/gadget/net2280.c
@@ -2257,9 +2257,7 @@ static void handle_stat0_irqs (struct net2280 *dev, u32 stat)
else
dev->gadget.speed = USB_SPEED_FULL;
net2280_led_speed (dev, dev->gadget.speed);
- DEBUG (dev, "%s speed\n",
- (dev->gadget.speed == USB_SPEED_HIGH)
- ? "high" : "full");
+ DEBUG(dev, "%s\n", usb_speed_string(dev->gadget.speed));
}
ep = &dev->ep [0];
diff --git a/drivers/usb/gadget/printer.c b/drivers/usb/gadget/printer.c
index 5d3e697b7d5d..68a0efbc2719 100644
--- a/drivers/usb/gadget/printer.c
+++ b/drivers/usb/gadget/printer.c
@@ -962,23 +962,15 @@ printer_set_config(struct printer_dev *dev, unsigned number)
usb_gadget_vbus_draw(dev->gadget,
dev->gadget->is_otg ? 8 : 100);
} else {
- char *speed;
unsigned power;
power = 2 * config_desc.bMaxPower;
usb_gadget_vbus_draw(dev->gadget, power);
- switch (gadget->speed) {
- case USB_SPEED_FULL: speed = "full"; break;
-#ifdef CONFIG_USB_GADGET_DUALSPEED
- case USB_SPEED_HIGH: speed = "high"; break;
-#endif
- default: speed = "?"; break;
- }
-
dev->config = number;
- INFO(dev, "%s speed config #%d: %d mA, %s\n",
- speed, number, power, driver_desc);
+ INFO(dev, "%s config #%d: %d mA, %s\n",
+ usb_speed_string(gadget->speed),
+ number, power, driver_desc);
}
return result;
}
diff --git a/drivers/usb/gadget/s3c-hsotg.c b/drivers/usb/gadget/s3c-hsotg.c
index 39b134dec94c..a552453dc946 100644
--- a/drivers/usb/gadget/s3c-hsotg.c
+++ b/drivers/usb/gadget/s3c-hsotg.c
@@ -1951,30 +1951,26 @@ static void s3c_hsotg_irq_enumdone(struct s3c_hsotg *hsotg)
case S3C_DSTS_EnumSpd_FS:
case S3C_DSTS_EnumSpd_FS48:
hsotg->gadget.speed = USB_SPEED_FULL;
- dev_info(hsotg->dev, "new device is full-speed\n");
-
ep0_mps = EP0_MPS_LIMIT;
ep_mps = 64;
break;
case S3C_DSTS_EnumSpd_HS:
- dev_info(hsotg->dev, "new device is high-speed\n");
hsotg->gadget.speed = USB_SPEED_HIGH;
-
ep0_mps = EP0_MPS_LIMIT;
ep_mps = 512;
break;
case S3C_DSTS_EnumSpd_LS:
hsotg->gadget.speed = USB_SPEED_LOW;
- dev_info(hsotg->dev, "new device is low-speed\n");
-
/* note, we don't actually support LS in this driver at the
* moment, and the documentation seems to imply that it isn't
* supported by the PHYs on some of the devices.
*/
break;
}
+ dev_info(hsotg->dev, "new device is %s\n",
+ usb_speed_string(hsotg->gadget.speed));
/* we should now know the maximum packet size for an
* endpoint, so set the endpoints to a default value. */
diff --git a/drivers/usb/gadget/udc-core.c b/drivers/usb/gadget/udc-core.c
index 05ba47214361..5e77a46a429a 100644
--- a/drivers/usb/gadget/udc-core.c
+++ b/drivers/usb/gadget/udc-core.c
@@ -375,23 +375,8 @@ static ssize_t usb_udc_speed_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
- struct usb_gadget *gadget = udc->gadget;
-
- switch (gadget->speed) {
- case USB_SPEED_LOW:
- return snprintf(buf, PAGE_SIZE, "low-speed\n");
- case USB_SPEED_FULL:
- return snprintf(buf, PAGE_SIZE, "full-speed\n");
- case USB_SPEED_HIGH:
- return snprintf(buf, PAGE_SIZE, "high-speed\n");
- case USB_SPEED_WIRELESS:
- return snprintf(buf, PAGE_SIZE, "wireless\n");
- case USB_SPEED_SUPER:
- return snprintf(buf, PAGE_SIZE, "super-speed\n");
- case USB_SPEED_UNKNOWN: /* FALLTHROUGH */
- default:
- return snprintf(buf, PAGE_SIZE, "UNKNOWN\n");
- }
+ return snprintf(buf, PAGE_SIZE, "%s\n",
+ usb_speed_string(udc->gadget->speed));
}
static DEVICE_ATTR(speed, S_IRUSR, usb_udc_speed_show, NULL);
diff --git a/drivers/usb/misc/usbtest.c b/drivers/usb/misc/usbtest.c
index 930962f49276..bd6d00802eab 100644
--- a/drivers/usb/misc/usbtest.c
+++ b/drivers/usb/misc/usbtest.c
@@ -2300,25 +2300,8 @@ usbtest_probe(struct usb_interface *intf, const struct usb_device_id *id)
usb_set_intfdata(intf, dev);
dev_info(&intf->dev, "%s\n", info->name);
- dev_info(&intf->dev, "%s speed {control%s%s%s%s%s} tests%s\n",
- ({ char *tmp;
- switch (udev->speed) {
- case USB_SPEED_LOW:
- tmp = "low";
- break;
- case USB_SPEED_FULL:
- tmp = "full";
- break;
- case USB_SPEED_HIGH:
- tmp = "high";
- break;
- case USB_SPEED_SUPER:
- tmp = "super";
- break;
- default:
- tmp = "unknown";
- break;
- }; tmp; }),
+ dev_info(&intf->dev, "%s {control%s%s%s%s%s} tests%s\n",
+ usb_speed_string(udev->speed),
info->ctrl_out ? " in/out" : "",
rtest, wtest,
irtest, iwtest,
diff --git a/drivers/usb/usb-common.c b/drivers/usb/usb-common.c
new file mode 100644
index 000000000000..d29503e954ab
--- /dev/null
+++ b/drivers/usb/usb-common.c
@@ -0,0 +1,35 @@
+/*
+ * Provides code common for host and device side USB.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2.
+ *
+ * If either host side (ie. CONFIG_USB=y) or device side USB stack
+ * (ie. CONFIG_USB_GADGET=y) is compiled in the kernel, this module is
+ * compiled-in as well. Otherwise, if either of the two stacks is
+ * compiled as module, this file is compiled as module as well.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/usb/ch9.h>
+
+const char *usb_speed_string(enum usb_device_speed speed)
+{
+ static const char *const names[] = {
+ [USB_SPEED_UNKNOWN] = "UNKNOWN",
+ [USB_SPEED_LOW] = "low-speed",
+ [USB_SPEED_FULL] = "full-speed",
+ [USB_SPEED_HIGH] = "high-speed",
+ [USB_SPEED_WIRELESS] = "wireless",
+ [USB_SPEED_SUPER] = "super-speed",
+ };
+
+ if (speed < 0 || speed >= ARRAY_SIZE(names))
+ speed = USB_SPEED_UNKNOWN;
+ return names[speed];
+}
+EXPORT_SYMBOL_GPL(usb_speed_string);
+
+MODULE_LICENSE("GPL");
diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h
index 1ded281eff88..f32a64e57f97 100644
--- a/include/linux/usb/ch9.h
+++ b/include/linux/usb/ch9.h
@@ -868,6 +868,18 @@ enum usb_device_speed {
USB_SPEED_SUPER, /* usb 3.0 */
};
+#ifdef __KERNEL__
+
+/**
+ * usb_speed_string() - Returns human readable-name of the speed.
+ * @speed: The speed to return human-readable name for. If it's not
+ * any of the speeds defined in usb_device_speed enum, string for
+ * USB_SPEED_UNKNOWN will be returned.
+ */
+extern const char *usb_speed_string(enum usb_device_speed speed);
+
+#endif
+
enum usb_device_state {
/* NOTATTACHED isn't in the USB spec, and this state acts
* the same as ATTACHED ... but it's clearer this way.