commit 0ba4581c upstream.

The 5 volt detect functionality broke in 3.14: the code reads IO register 0x70
again after it has already been cleared. Instead it should use the cached
irq_reg_0x70 value and the io_write to 0x71 to clear 0x70 can be dropped since
this has already been done.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>