The original report from Nikhil was that if data_offset > 0 and bytesused == 0,
then the check in __verify_length() would fail, even though the spec says that
if bytes_used == 0, then it will be replaced by the actual length of the
buffer.

After digging into it a bit more I realized that there were several other
things wrong:

- in __verify_length() it would use the application-provided length value
  for USERPTR and the vb2 core length for other memory models, but it
  should have used the application-provided length as well for DMABUF.

- in __fill_vb2_buffer() on the other hand it would replace bytesused == 0
  by the application-provided length, even for MMAP buffers where the
  length is determined by the vb2 core.

- in __fill_vb2_buffer() it tries to figure out if all the planes have
  bytesused == 0 before it will decide to replace bytesused by length.
  However, the spec makes no such provision, and it makes for convoluted
  code. So just replace any bytesused == 0 by the proper length.
  The idea behind this was that you could use bytesused to signal empty
  planes, something that is currently not supported. But that is better
  done in the future by using one of the reserved fields in strucy v4l2_plane.

This patch fixes all these issues.

Regards,

	Hans
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Reported-by: NNikhil Devshatwar <nikhil.nd@ti.com>
Cc: Nikhil Devshatwar <nikhil.nd@ti.com>
Acked-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Fill FMT buffer size field in order to inform app which will be
used streaming buffer size. Currently driver doesn't allow buffer
size value proposed by application.

Cc: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

SDR API is very new and surprises may occur. Due to that print
notice to remind possible users.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Enable two native formats, V4L2_SDR_FMT_CS8 and V4L2_SDR_FMT_CS14LE.
Move emulated formats behind module parameter.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

MSi3101 driver is moved out of staging and renamed.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Move msi3101 out of staging and rename to msi2500.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Fill FMT buffer size field in order to inform app which will be
used streaming buffer size. Currently driver doesn't allow buffer
size value proposed by application.

Cc: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

New field buffersize was added to inform application maximum
buffer size used. Add it to documentation too.

Cc: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Fill FMT buffer size field in order to inform app which will be
used streaming buffer size. Currently driver doesn't allow buffer
size value proposed by application.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Add buffer size field to struct v4l2_sdr_format. It is used for
negotiate streaming buffer size between application and driver.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

This is needed for PCTV 522e support.
Signed-off-by: NMatthias Schwarzott <zzam@gentoo.org>
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

This is needed for PCTV 522e support.
Signed-off-by: NMatthias Schwarzott <zzam@gentoo.org>
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Modify all users of si2157_config to correctly initialize all not
listed values to 0.
Signed-off-by: NMatthias Schwarzott <zzam@gentoo.org>
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Modify all users of si2157_config to correctly initialize all not
listed values to 0.
Signed-off-by: NMatthias Schwarzott <zzam@gentoo.org>
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The struct prototype is defined at the beginning of the code as
"si2157_ops" but the real struct is called "si2157_tuner_ops".

This is causing the name to be empty on this info msg: si2157 16-0060:
si2157: found a '' in cold state

[crope@iki.fi: commit msg from Luis email reply]
Signed-off-by: NOlli Salonen <olli.salonen@iki.fi>
Cc: Luis Alves <ljalvs@gmail.com>
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

This adds support for the Si2168-A20 firmware download.

Extracting the firmware:

wget http://www.tbsdtv.com/download/document/tbs6281/tbs6281-t2-t-driver_v1.0.0.6.zip
unzip tbs6281-t2-t-driver_v1.0.0.6.zip
dd if=tbs-6281_x64/tbs6281_64.sys of=dvb-demod-si2168-a20-01.fw count=28656 bs=1 skip=1625088

md5sum:
32e06713b33915f674bfb2c209beaea5 /lib/firmware/dvb-demod-si2168-a20-01.fw
Signed-off-by: NLuis Alves <ljalvs@gmail.com>
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Testing demod presence on probe fails if the demod was sleep mode.
Signed-off-by: NLuis Alves <ljalvs@gmail.com>
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

In case of failure the return value was always 0. Return proper
error code (ENODEV) instead.
Signed-off-by: NLuis Alves <ljalvs@gmail.com>
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Improve scanning performance by setting property 0301 with a value
from Windows driver.
Signed-off-by: NOlli Salonen <olli.salonen@iki.fi>
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

This patch adds symbol rate setting to the driver.
Signed-off-by: NLuis Alves <ljalvs@gmail.com>
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Video4Linux2 driver for AirSpy SDR device.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Print notice on driver load: "SDR API is still slightly
experimental and functionality changes may follow". It is just
remind possible used SDR API is very new and surprises may occur.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Move it out of staging into media like all the other SDR drivers
too. There is no good reasons to keep these SDR drivers in staging.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

v4l2-compliance is now happy with frequency ranges where both lower
and upper limit is same.

Cc: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

It is moved out of staging to media.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

SDR API is very new and surprises may occur. Due to that print
notice to remind possible users.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Move emulated format behind module parameter as those are not
supported. Format conversions will be on library eventually.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Move rtl2832_sdr driver module from staging to media.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Mirics MSi001 and MSi2500 drivers uses SPI bus. Due to that we need
auto-select it too.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Add software defined radio device support for media Kconfig.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The driver moved out of staging. Update MAINTAINERS
accordingly.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Move MSi001 driver from staging to drivers/media/tuners/.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

drivers/staging/media/airspy/airspy.c: In function 'airspy_stop_streaming':
drivers/staging/media/airspy/airspy.c:569:6: warning: variable 'ret' set but not used [-Wunused-but-set-variable]
  int ret;
      ^

Cc: Antti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

V4L2_SDR_FMT_CS14LE is complex signed 14-bit sample format, used
for software defined radio devices.

[m.chehab@samsung.com: remove V4L2_FL_USE_FH_PRIO setting to avoid
 compilation breakage, as this flag doesn't exist anymore]
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

V4L2_SDR_FMT_CS14LE - Complex signed 14-bit IQ sample
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

V4L2_SDR_FMT_CS8 is complex signed 8-bit sample format, used for
software defined radio devices.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

V4L2_SDR_FMT_CS8 - Complex signed 8-bit IQ sample
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

AirSpy SDR driver.

Thanks to Youssef Touil and Benjamin Vernoux for support, help and
hardware!
http://airspy.com/Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Document V4L2_SDR_FMT_RU12LE format. It is real unsigned 12-bit
little endian sample inside 16-bit space. Used by software defined
radio devices.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

V4L2_SDR_FMT_RU12LE - Real unsigned 12-bit little endian sample
inside 16-bit (2 byte). V4L2 FourCC: RU12.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>