xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

usb: common: introduce of_usb_get_maximum_speed()

Browse Source 
this helper will be used for controllers which
want to work at a lower speed even though they
support higher USB transfer rates.

One such case is Texas Instruments' AM437x
SoC where it uses a USB3 controller without
a USB3 PHY, rendering the controller USB2-only.

Signed-off-by: Felipe Balbi <balbi@ti.com>
This commit is contained in:
Felipe Balbi
2013-06-30 13:56:45 +03:00
parent 410aee70f0
commit 1494a1f62b
3 changed files with 70 additions and 11 deletions
Download Patch File Download Diff File Expand all files Collapse all files

49
drivers/usb/usb-common.c
View File

@@ -43,20 +43,20 @@ const char *usb_otg_state_string(enum usb_otg_state state)
}
EXPORT_SYMBOL_GPL(usb_otg_state_string);
static const char *const speed_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",
};
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))
if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
speed = USB_SPEED_UNKNOWN;
return names[speed];
return speed_names[speed];
}
EXPORT_SYMBOL_GPL(usb_speed_string);
@@ -112,6 +112,33 @@ enum usb_dr_mode of_usb_get_dr_mode(struct device_node *np)
return USB_DR_MODE_UNKNOWN;
}
EXPORT_SYMBOL_GPL(of_usb_get_dr_mode);
/**
* of_usb_get_maximum_speed - Get maximum requested speed for a given USB
* controller.
* @np: Pointer to the given device_node
*
* The function gets the maximum speed string from property "maximum-speed",
* and returns the corresponding enum usb_device_speed.
*/
enum usb_device_speed of_usb_get_maximum_speed(struct device_node *np)
{
const char *maximum_speed;
int err;
int i;
err = of_property_read_string(np, "maximum-speed", &maximum_speed);
if (err < 0)
return USB_SPEED_UNKNOWN;
for (i = 0; i < ARRAY_SIZE(speed_names); i++)
if (strcmp(maximum_speed, speed_names[i]) == 0)
return i;
return USB_SPEED_UNKNOWN;
}
EXPORT_SYMBOL_GPL(of_usb_get_maximum_speed);
#endif
MODULE_LICENSE("GPL");