While developing MST support I noticed I often got the wrong data
back from a transaction, in a racy fashion. I noticed the scratch
space wasn't locked against concurrent users.
Based on a patch by Alex, but I've made it a bit more obvious when
things are locked.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
The i2c and aux buses use the same pads so add
a mutex to protect access to the pads.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Move prototype declaration of function radeon_atom_copy_swap() to header
file drm/radeon/radeon_mode.h because it is used by more than one file.
This eliminates the following warnings in drm/radeon/atombios_dp.c:
drivers/gpu/drm/radeon/atombios_dp.c:53:6: warning: no previous prototype for ‘radeon_atom_copy_swap’ [-Wmissing-prototypes]
Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Useless to count the register index in number of bytes we are writing.
Fixes a regression with hw i2c enabled.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
These fixes make writes work properly. Previously
only reads worked. Note that this feature is off
by default.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Need to swap the data fetched over i2c properly. This
is the same fix as the endian fix for aux channel
transactions.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Convert #include "..." to #include <path/...> in drivers/gpu/.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
Starting with DCE3 hardware, atom contains a general purpose
ProcessI2cChannelTransaction similar to ProcessAuxChannelTransaction.
Add an implementation using the atom tables for DCE3+ hardware.
This should be a little less CPU intensive than bit banging and
may work better in certain cases.
Enable it by setting the radeon hw_i2c module parameter to 1. E.g.,
radeon.hw_i2c=1
on the kernel command line in grub.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>