vlv_dpio_read/write should be describe more in PHY centric instead of
display controller centric.
Create a enum dpio_channel for channel index and enum dpio_phy for PHY
index.  This should better to gather for upcoming platform.

v2: Rebase the code based on
drm/i915/vlv: Fix typo in the DPIO register define.

v3: Rename vlv_phy to dpio_phy_iosf_port and define additional macro
DPIO_PHY, and remove unrelated change. (Ville)
Suggested-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NChon Ming Lee <chon.ming.lee@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

For modifying self-refresh exit latency.
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

So digging out the right ones is a little easier.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The patch doesn't contain functional change, but is to prepare for
future platform which has different DPIO phy.  The additional pipe
parameter will use to select which phy to target for.

v2: Update the commit message and add static for the new function.
(Jani/Ville)
Signed-off-by: NChon Ming Lee <chon.ming.lee@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Acked-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

For GPIO NC, CCK, CCU, and GPS CORE.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NShobhit Kumar <shobhit.kumar@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We never check the return values, and there's not much we could do on
errors anyway. Just simplify the signatures. No functional changes.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Rename all VLV IOSF sideband register accessor functions to
vlv_<port>_{read,write}. No functional changes.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Both the intel_dpio_{read,write} and valleyview_{punit,nc}_{read,write}
use the IOSF sideband interface. They access the same registers and do
mostly the same stuff, but no shared code. There are even duplicate
register defines for the same registers. Both have locking, but the
former use dpio_lock and the latter rps.hw_lock. It's racy.

This patch refactors the sideband access to a single function that
expects dpio_lock to be held. The dpio_lock is only used for sideband
stuff, so it's a better match than rps.hw_lock for the purpose. The rps
stuff still needs rps.hw_lock, since it's used to protect more than just
the register access, so rps code will need to hold both locks.

Based on the work by Shobhit Kumar <shobhit.kumar@intel.com> and Yogesh
Mohan Marimuthu <yogesh.mohan.marimuthu@intel.com>.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Group both the HSW/LPT SBI interface and VLV IOSF sideband register
accessor functions into a new file. No functional changes.

v2: also move intel_sbi_{read,write} (Daniel)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>