Commit Graph

9 Commits

Author SHA1 Message Date
Ezequiel Garcia 34e2acc8df [media] tw686x: Add support for DMA scatter-gather mode
Now that the driver has the infrastructure to support more
DMA modes, let's add the DMA scatter-gather mode.

In this mode, the device delivers sequential top-bottom
frames. The scatter-gather logic is based on staging's
tw686x-kh driver (by Krzysztof Ha?asa).

Tested-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-06-28 07:50:09 -03:00
Ezequiel Garcia 11a1697404 [media] tw686x: Add support for DMA contiguous interlaced frame mode
Now that the driver has the infrastructure to support more
DMA modes, let's add the DMA contiguous interlaced frame mode.

In this mode, the DMA P and B buffers are programmed with
the user-provided buffers. When a P (or B) frame is ready,
a new buffer is dequeued into P (or B).

In addition to interlaced fields, the device can also be
programmed to deliver alternate fields. Only interlaced
mode is supported for now.

Tested-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-06-28 07:48:28 -03:00
Ezequiel Garcia f8afaa8dbc [media] tw686x: Introduce an interface to support multiple DMA modes
Let's set the corner stone to support all the DMA modes
available on this device.

For stability reasons, the driver is currently setting DMA frame
mode, and using single DMA buffers to get the P and B buffers.
Each frame is then memcpy'ed into the user buffer.

However, other platforms might be interested in avoiding this
memcpy, or in taking advantage of the chip's DMA scatter-gather
capabilities.

To achieve this, this commit introduces a "dma_mode" module parameter,
and a tw686x_dma_ops struct. This will allow to define functions to
alloc/free DMA buffers, and to return the frames to userspace.

The memcpy-based method described above is named as dma_mode="memcpy".
Current alloc/free functions are renamed as tw686x_memcpy_xxx,
and are now used through a memcpy_dma_ops.

Tested-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-06-28 07:47:40 -03:00
Mauro Carvalho Chehab 45c175c4ae [media] tw686x: avoid going past array
Fix those two warnings:
	drivers/media/pci/tw686x/tw686x-video.c:69 tw686x_fields_map() error: buffer overflow 'std_525_60' 31 <= 31
	drivers/media/pci/tw686x/tw686x-video.c:73 tw686x_fields_map() error: buffer overflow 'std_625_50' 26 <= 26

I had those changes at the last version of my patch, but I ended
by merging the previous version by mistake.

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2016-04-26 06:38:53 -03:00
Mauro Carvalho Chehab 363d79f1d5 [media] tw686x: Don't go past array
Depending on the compiler version, currently it produces the
following warnings:
	tw686x-video.c: In function 'tw686x_video_init':
	tw686x-video.c:65:543: warning: array subscript is above array bounds [-Warray-bounds]

This is actually bogus with the current code, as it currently
hardcodes the framerate to 30 frames/sec, however a potential
use after the array size could happen when the driver adds support
for setting the framerate. So, fix it.

Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2016-04-25 09:45:50 -03:00
Hans Verkuil bde569874b [media] tw686x-video: test for 60Hz instead of 50Hz
When determining if the standard is 50 or 60 Hz it is standard
practice to test for 60 Hz instead of 50 Hz.

This doesn't matter normally, except if the user specifies both
60 and 50 Hz standards.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2016-04-25 08:02:50 -03:00
Ezequiel Garcia 1c9f47195e [media] tw686x: Specify that the DMA is 32 bits
Set vb2_queue.gfp_flags to GFP_DMA32. Otherwise it will start to
create bounce buffers which is something you want to avoid since
those are in limited supply.

Without this patch, DMA scatter-gather may not work because
machines can ran out of buffers easily.

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2016-04-20 13:43:12 -03:00
Hans Verkuil 2e2dedb96d [media] tw686x: add missing statics
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2016-04-20 13:42:32 -03:00
Ezequiel Garcia 704a84ccdb [media] media: Support Intersil/Techwell TW686x-based video capture cards
This commit introduces the support for the Techwell TW686x video
capture IC. This hardware supports a few DMA modes, including
scatter-gather and frame (contiguous).

This commit makes little use of the DMA engine and instead has
a memcpy based implementation. DMA frame and scatter-gather modes
support may be added in the future.

Currently supported chips:
- TW6864 (4 video channels),
- TW6865 (4 video channels, not tested, second generation chip),
- TW6868 (8 video channels but only 4 first channels using
           built-in video decoder are supported, not tested),
- TW6869 (8 video channels, second generation chip).

[mchehab@osg.samsung.com: make checkpatch happy by using "unsigned int"
  instead  of just "unsigned"]
Cc: Krzysztof Halasa <khalasa@piap.pl>
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Tested-by: Hans Verkuil <hans.verkuil@cisco.com>

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2016-04-20 13:37:32 -03:00