disp: msm: dp: add support for 3.75:1 compression

Currently the DP driver always uses a compression ratio of 3, if
DSC is enabled. So if the sink supports 30bpp, the compressed
output is set to 10bpp. But since the hardware supports
compressing this to 8bpp, it would require less link bandwidth
than 10bpp compressed output. For compliance testing, the
test equipment limits the link bandwidth based on the most
efficient compression ratio and for some resolutions there
is not enough link bandwidth for 3:1 compression.

This change always sets the compression output to 8bpp to
minimize the link bandwidth utilization.

Change-Id: Ifa6129444c2bab4e9c357ddfe49f76efa5b04be0
Signed-off-by: Rajkumar Subbiah <rsubbia@codeaurora.org>

msm/msm_drv.h

@@ -681,17 +681,22 @@ struct msm_display_vdc_info {
 
 /**
  * struct msm_compression_info - defined panel compression
+ * @enabled:          enabled/disabled
  * @comp_type:        type of compression supported
  * @comp_ratio:       compression ratio
+ * @src_bpp:          bits per pixel before compression
+ * @tgt_bpp:          bits per pixel after compression
  * @dsc_info:         dsc configuration if the compression
  *                    supported is DSC
  * @vdc_info:         vdc configuration if the compression
  *                    supported is VDC
  */
 struct msm_compression_info {
+	bool enabled;
 	enum msm_display_compression_type comp_type;
 	u32 comp_ratio;
-
+	u32 src_bpp;
+	u32 tgt_bpp;
 	union{
 		struct msm_display_dsc_info dsc_info;
 		struct msm_display_vdc_info vdc_info;