Re: [PATCH] ARM: dts: am33xx: fix DMA support for the second USB interface

Yegor Yefremov
2014-04-29T06:16:36Z

On Tue, Apr 29, 2014 at 6:31 AM, George Cherian <george.cherian@ti.com> wrote:
> On 4/28/2014 9:47 PM, Yegor Yefremov wrote:
>>
>> On Mon, Apr 28, 2014 at 4:25 PM, George Cherian <george.cherian@ti.com>
>> wrote:
>>>
>>> On 4/28/2014 2:07 PM, yegorslists@googlemail.com wrote:
>>>>
>>>> From: Yegor Yefremov <yegorslists@googlemail.com>
>>>>
>>>> This patch creates unique DMA channels for the second USB
>>>> interface, otherwise the second USB interface is not usable
>>>> at all.
>>>
>>> MUSB_DMA_NUM_CHANNELS is 15, so if you pass any dma-names > 15 (>
>>> rx15/tx15),
>>> the dma_controller_create in musb_core.c fails and it falls back to PIO
>>> mode.
>>
>> What's the proper fix for the DMA issue?
>
> I could not understand what issue you are referring to.
> In my setup I use both BBB and BBW (Beagle Bone Black/White)with one USB in
> host (USB1)
> and one USB in gadget (USB0). I dont see any issues with DMA.
>
> Can you be more specific?

I've totally overlooked the DMA channel allocation errors (though usb0
in host mode was working, usb1 in OTG not).

of_get_named_gpiod_flags: can't parse gpios property of node
'/ocp/usb@47400000/usb-phy@47401300[0]'
47401300.usb-phy supply vcc not found, using dummy regulator
musb-hdrc musb-hdrc.0.auto: Failed to request rx1.
musb-hdrc musb-hdrc.0.auto: musb_init_controller failed with status -517
platform musb-hdrc.0.auto: Driver musb-hdrc requests probe deferral
of_get_named_gpiod_flags: can't parse gpios property of node
'/ocp/usb@47400000/usb-phy@47401b00[0]'
47401b00.usb-phy supply vcc not found, using dummy regulator
musb-hdrc musb-hdrc.1.auto: Failed to request rx1.
musb-hdrc musb-hdrc.1.auto: musb_init_controller failed with status -517
platform musb-hdrc.1.auto: Driver musb-hdrc requests probe deferral

This patch fixes the issue: "ARM: dts: am33xx: Move the cppi41dma node
so it's probed early"

Thanks.

Yegor