disp: msm: Add support for seamless panel operating mode switch

DSI display may support video mode and command mode both and it may
support transition between these two modes.
This change adds seamless transition between these two modes for DSI
display by avoiding crtc enable/disable and panel power on/off
during modeset.

Change-Id: Id7ddaef7d1f0f7cc7d52283755bad53a246adec6
Signed-off-by: Lei Chen <chenlei@codeaurora.org>

msm/msm_kms.h

@@ -38,6 +38,8 @@
 #define MSM_MODE_FLAG_SEAMLESS_DMS			(1<<2)
 /* Request to switch the fps */
 #define MSM_MODE_FLAG_SEAMLESS_VRR			(1<<3)
+/* Request to switch the panel mode */
+#define MSM_MODE_FLAG_SEAMLESS_POMS			(1<<4)
 
 /* As there are different display controller blocks depending on the
  * snapdragon version, the kms support is split out and the appropriate
@@ -212,6 +214,13 @@ static inline bool msm_is_mode_seamless_vrr(const struct drm_display_mode *mode)
 		: false;
 }
 
+static inline bool msm_is_mode_seamless_poms(
+		const struct drm_display_mode *mode)
+{
+	return mode ? (mode->private_flags & MSM_MODE_FLAG_SEAMLESS_POMS)
+		: false;
+}
+
 static inline bool msm_needs_vblank_pre_modeset(
 		const struct drm_display_mode *mode)
 {