2010/8/28 Matthew Lai <cyberfish@wecheer.com>

I have a USB device (webcam) that will draw more than 100mA, but I don't
want to use a hub, so I'm going to splice the USB cable, and supply my
own 5V.

However, I still need the Overo to "know" it can supply more than 100mA,
otherwise it will just reject the device.

Someone apparently had the exact same problem, and solved it by changing
drivers/*usb*/host/ehci.h in the kernel.

However, those lines don't exist on 2.6.34-r88 anymore, and I looked in
another few files but couldn't recognize what I can change.

Has anyone done it? Or can someone shed some light?


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Try and have a look in arch/arm/mach-omap2/board-overo.c at line 416 here you can change the 
power for the USB OTG port.  

static struct omap_musb_board_data musb_board_data = {
.interface_type = MUSB_INTERFACE_ULPI,
.mode = MUSB_OTG,
.power = 100,

Furthermore in kernel version 2.6.33 i had to change arch/arm/mach-omap/usb-msub.c
line 108 from " musb_plat.power = board_data->power >> 1; " to "musb_plat.power = board_data->power;"
I am not sure if this is still necessary but this prohibited me from specifying a supply of more than 250 mA
removing the right shift allowed me to specify 500 mA.