Re: [PATCH 3/4] usb: remove OMAP USB Device Controller and OHCI support for OMAP1/2 chips
From: Arnd Bergmann
Date: Thu Jan 12 2023 - 09:42:39 EST
On Thu, Jan 12, 2023, at 15:05, Aaro Koskinen wrote:
> On Thu, Jan 12, 2023 at 11:19:53AM +0100, Arnd Bergmann wrote:
>> On Thu, Jan 12, 2023, at 10:53, Tony Lindgren wrote:
>>
>> So if we want to kill off the old DMA stuff there is actually
>> a choice between either making omap_udc PIO-only or converting
>> it to use the standard dmaengine interface.
>
> I use this driver on Palm TE and 770, and without it those boards would
> be useless for my use cases. Also DMA doubles the throughput, probably
> also power usage is smaller.
Ok, if the performance is important, converting to dmaengine
is probably best. Do you know if this is just a straightforward
replacement of the function calls, or are there technical reasons
why it's not using the dmaengine interface yet?
Arnd