mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-02 07:04:24 +00:00
0cfbd328d6
With this patch, USB activity can be signaled by blinking a LED. There are two triggers, one for activity on USB host and one for USB gadget. Both triggers should work with all host/device controllers. Tested only with musb. Performace: I measured performance overheads on ARM Cortex-A8 (TI AM335x) running on 600 MHz. Duration of usb_led_activity(): - with no LED attached to the trigger: 2 ± 1 µs - with one GPIO LED attached to the trigger: 2 ± 1 µs or 8 ± 2 µs (two peaks in histogram) Duration of functions calling usb_led_activity() (with this patch applied and no LED attached to the trigger): - __usb_hcd_giveback_urb(): 10 - 25 µs - usb_gadget_giveback_request(): 2 - 6 µs Signed-off-by: Michal Sojka <sojka@merica.cz> Acked-by: Felipe Balbi <balbi@ti.com> Tested-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
9 lines
201 B
Makefile
9 lines
201 B
Makefile
#
|
|
# Makefile for the usb common parts.
|
|
#
|
|
|
|
obj-$(CONFIG_USB_COMMON) += usb-common.o
|
|
usb-common-y += common.o
|
|
usb-common-$(CONFIG_USB_LED_TRIG) += led.o
|
|
|
|
obj-$(CONFIG_USB_OTG_FSM) += usb-otg-fsm.o
|