If you have a cluster of controls that is a mix of volatile and non-volatile
controls, then requesting the value of the volatile control would fail if the
master control of that cluster was non-volatile. The code assumed that the
volatile state of the master control was the same for all other controls in
the cluster.

This is now fixed.

In addition, it was clear from bugs in some drivers that it was confusing that
the ctrl->cur union had to be used in g_volatile_ctrl. Several drivers used the
'new' values instead. The framework was changed so that drivers now set the new
value instead of the current value.

This has an additional benefit as well: the volatile values are now only stored
in the 'new' value, leaving the current value alone. This is useful for
autofoo/foo control clusters where you want to have a 'foo' control act like a
volatile control if 'autofoo' is on, but as a normal control when it is off.

Since with this change the cur value is no longer overwritten when g_volatile_ctrl
is called, you can use it to remember the original 'foo' value. For example:

autofoo = 0, foo = 10 and foo is non-volatile.

Now autofoo is set to 1 and foo is marked volatile. Retrieving the foo value
will get the volatile value. Set autofoo back to 0, which marks foo as non-
volatile again, and retrieving foo will get the old current value of 10.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Just like the video drivers, the right thing to do is to use
the per-subsystem version control.
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The function g_volatile_ctrl should change the current value rather than the
new value. These two drivers didn't do that, so the value is never reported
correctly.

In the future this will change since this behavior is clearly unexpected,
but for now fix these drivers first.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This module interfaces V4L2 subsystem and FM common module.
It registers itself with V4L2 as Radio module.
Signed-off-by: NManjunatha Halli <manjunatha_halli@ti.com>
Reviewed-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>