Adds a new uAPI for DVB to use streaming I/O which is implemented
based on videobuf2, using those new ioctls:
- DMX_REQBUFS: Request kernel to allocate buffers which count and size
are dedicated by user.
- DMX_QUERYBUF: Get the buffer information like a memory offset which
will mmap() and be shared with user-space.
- DMX_EXPBUF: Just for testing whether buffer-exporting success or not.
- DMX_QBUF: Pass the buffer to kernel-space.
- DMX_DQBUF: Get back the buffer which may contain TS data.
Originally developed by: Junghak Sung <jh1009.sung@samsung.com>, as
seen at:
https://patchwork.linuxtv.org/patch/31613/https://patchwork.kernel.org/patch/7334301/
The original patch was written before merging VB2-core functionalities
upstream. When such series was added, several adjustments were made,
fixing some issues with V4L2, causing the original patch to be
non-trivially rebased.
After rebased, a few bugs in the patch were fixed. The patch was
also enhanced it and polling functionality got added.
The main changes over the original patch are:
dvb_vb2_fill_buffer():
- Set the size of the outgoing buffer after while loop using
vb2_set_plane_payload;
- Added NULL check for source buffer as per normal convention
of demux driver, this is called twice, first time with valid
buffer second time with NULL pointer, if its not handled,
it will result in crash
- Restricted spinlock for only list_* operations
dvb_vb2_init():
- Restricted q->io_modes to only VB2_MMAP as its the only
supported mode
dvb_vb2_release():
- Replaced the && in if condiion with &, because otherwise
it was always getting satisfied.
dvb_vb2_stream_off():
- Added list_del code for enqueud buffers upon stream off
dvb_vb2_poll():
- Added this new function in order to support polling
dvb_demux_poll() and dvb_dvr_poll()
- dvb_vb2_poll() is now called from these functions
- Ported this patch and latest videobuf2 to lower kernel versions and
tested auto scan.
Co-developed-by: Junghak Sung <jh1009.sung@samsung.com>
[mchehab@s-opensource.com: checkpatch fixes]
Signed-off-by: Junghak Sung <jh1009.sung@samsung.com>
Signed-off-by: Geunyoung Kim <nenggun.kim@samsung.com>
Acked-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Acked-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Satendra Singh Thakur <satendra.t@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Satendra Singh Thakur