Re: [RFC PATCH] vb2: Stop allocating 'alloc_ctx', just set the device instead

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Hans,

On Monday 14 December 2015 15:36:04 Hans Verkuil wrote:
> (Before I post this as the 'final' patch and CC all the driver developers
> that are affected, I'd like to do an RFC post first. I always hated the
> alloc context for obfuscating what is really going on, but let's see what
> others think).
> 
> 
> Instead of allocating a struct that contains just a single device pointer,
> just pass that device pointer around. This avoids having to check for
> memory allocation errors and is much easier to understand since it makes
> explicit what was hidden in an opaque handle before.
> 
> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>

As most devices use the same allocation context for all planes, wouldn't it 
make sense to just store the struct device pointer in the queue structure ? 
The oddball driver that requires different allocation contexts (I'm thinking 
about s5p-mfc here, there might be a couple more) would have to set the 
allocation contexts properly in the queue_setup handler, but for all other 
devices you could just remove that code completely.

-- 
Regards,

Laurent Pinchart