diff options
| -rw-r--r-- | Documentation/devicetree/bindings/usb/generic.txt | 24 | ||||
| -rw-r--r-- | drivers/usb/usb-common.c | 49 | ||||
| -rw-r--r-- | include/linux/usb/of.h | 8 |
3 files changed, 70 insertions, 11 deletions
diff --git a/Documentation/devicetree/bindings/usb/generic.txt b/Documentation/devicetree/bindings/usb/generic.txt new file mode 100644 index 000000000000..477d5bb5e51c --- /dev/null +++ b/Documentation/devicetree/bindings/usb/generic.txt @@ -0,0 +1,24 @@ +Generic USB Properties + +Optional properties: + - maximum-speed: tells USB controllers we want to work up to a certain + speed. Valid arguments are "super-speed", "high-speed", + "full-speed" and "low-speed". In case this isn't passed + via DT, USB controllers should default to their maximum + HW capability. + - dr_mode: tells Dual-Role USB controllers that we want to work on a + particular mode. Valid arguments are "host", + "peripheral" and "otg". In case this attribute isn't + passed via DT, USB DRD controllers should default to + OTG. + +This is an attribute to a USB controller such as: + +dwc3@4a030000 { + compatible = "synopsys,dwc3"; + reg = <0x4a030000 0xcfff>; + interrupts = <0 92 4> + usb-phy = <&usb2_phy>, <&usb3,phy>; + maximum-speed = "super-speed"; + dr_mode = "otg"; +}; diff --git a/drivers/usb/usb-common.c b/drivers/usb/usb-common.c index 675384dabfe9..d771870a819e 100644 --- a/drivers/usb/usb-common.c +++ b/drivers/usb/usb-common.c @@ -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"); diff --git a/include/linux/usb/of.h b/include/linux/usb/of.h index a0ef405368b8..5a7cb9ebf0ef 100644 --- a/include/linux/usb/of.h +++ b/include/linux/usb/of.h @@ -7,16 +7,24 @@ #ifndef __LINUX_USB_OF_H #define __LINUX_USB_OF_H +#include <linux/usb/ch9.h> #include <linux/usb/otg.h> #include <linux/usb/phy.h> #if IS_ENABLED(CONFIG_OF) enum usb_dr_mode of_usb_get_dr_mode(struct device_node *np); +enum usb_device_speed of_usb_get_maximum_speed(struct device_node *np); #else static inline enum usb_dr_mode of_usb_get_dr_mode(struct device_node *np) { return USB_DR_MODE_UNKNOWN; } + +static inline enum usb_device_speed +of_usb_get_maximum_speed(struct device_node *np) +{ + return USB_SPEED_UNKNOWN; +} #endif #if IS_ENABLED(CONFIG_OF) && IS_ENABLED(CONFIG_USB_PHY) |