On Tue, Apr 5, 2016 at 8:35 PM, Stephen Warren swarren@wwwdotorg.org wrote:
On 04/05/2016 10:36 AM, Semen Protsenko wrote:
From: Sam Protsenko semen.protsenko@linaro.org
The description was borrowed from kernel, but allowed range was changed from 2..500 to 0..500, because some boards require this option to be 0.
Do they /require/ the value to be 0, or simply currently have it set to 0 because whoever set the value in U-Boot wasn't aware that a value of 0 could cause issues with some hosts?
I'd be tempted to keep the same range as the Linux kernel and bump all boards up to a minimum value of 2. Presumably there's some good reason the kernel chose a minimum of 2, and in practice I expect increasing all boards to 2 isn't going to make any negative difference.
diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
+config USB_GADGET_VBUS_DRAW
int "Maximum VBUS Power usage (2-500 mA)"range 0 500default 2helpSome devices need to draw power from USB when they areconfigured, perhaps to operate circuitry or to rechargebatteries. This is in addition to any local power supply,such as an AC adapter or batteries.Enter the maximum power your device draws through USB, inmilliAmperes. The permitted range of values is 2 - 500 mA;0 mA would be legal, but can make some hosts misbehave.In particular, I'm thinking of that last sentence.
I've sent v2 of this patch. Please review.