Dynamic static allocation is evil, as Kernel stack is too low, and
compilation complains about it on some archs:
       drivers/media/dvb-frontends/stv090x.c:750:1: warning: 'stv090x_write_regs.constprop.6' uses dynamic stack allocation [enabled by default]
Instead, let's enforce a limit for the buffer. Considering that I2C
transfers are generally limited, and that devices used on USB has a
max data length of 64 bytes for	the control URBs.
So, it seem safe to use 64 bytes as the hard limit for all those devices.
 On most cases, the limit is a way lower than that, but	this limit
is small enough to not affect the Kernel stack, and it is a no brain
limit, as using smaller ones would require to either carefully each
driver or to take a look on each datasheet.

Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Reviewed-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

goto err and goto err_gateoff before mutex_lock(&state->internal->demod_lock)
lead to unlock of unheld mutex in stv090x_sleep().
Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Manu Abraham <abraham.manu@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

Sometimes there is a problem when trying to access the non-existing registers
of the second demodulator path on the STV0903.

This change removes the calls in case the driver is used on a STV0903.

Signed-off-by: Andreas Regel <andreas.regel@gmx.de>
Acked-by: Manu Abraham <manu@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

Adds support for filtering multistream TS using stv090x hardware.

Signed-off-by: Evgeny Plehov <EvgenyPlehov@ukr.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

Raise the DVB frontends one level up, as the intention is to remove
the drivers/media/dvb directory.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>