The i2c and aux buses use the same pads so add
a mutex to protect access to the pads.
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NChristian 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: NRashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

When probing the bus, we need to set the byte count
to 0 rather than 1.

v2: Don't count the first byte.

bug:
https://bugzilla.kernel.org/show_bug.cgi?id=66241Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

Useless to count the register index in number of bytes we are writing.

Fixes a regression with hw i2c enabled.
Signed-off-by: NJerome Glisse <jglisse@redhat.com>
Signed-off-by: NAlex 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: NAlex 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: NAlex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

Convert #include "..." to #include <path/...> in drivers/gpu/.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NDave Airlie <airlied@redhat.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NDave 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: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>