Re: [PATCH] musb: Add workqueue for URB giveback

[David Vrabel <david.vrabel@csr.com>]

Ajay Kumar Gupta wrote:
> Current musb host driver does the giveback of completed urb first and
> then start the next request. This is significantly affecting the streaming
> from an USB camera wherein we observe huge delay between the two IN tokens
> from musb host. This is due to the fact that UVC driver is doing decoding
> and further processing in giveback context.
> 
> The patch tries to defer the giveback part to a workqueue and continues
> with the start of new request in completion path.

Suggest allocating a per-urb structure when a new URB is enqueued.  This
structure contains the completion/giveback work item.  This avoids
having to a) allocate memory on completion; b) create a second queue
structure.

David
-- 
David Vrabel, Senior Software Engineer, Drivers
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