gspca: Protect dq_callback() against simultaneous USB exchanges.
Temporary buffer for USB exchanges added in the device struct.
(all) Use a temporary buffer for all USB exchanges.
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Done for conex, etoms, pac7311, sonixj, t613 and tv8532.
Code cleanup for some other subdrivers.
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>