drm/hdcp: Max MST content streams

Let's define Maximum MST content streams up to four
generically which can be supported by modern display
controllers.

Cc: Sean Paul <seanpaul@chromium.org>
Cc: Ramalingam C <ramalingam.c@intel.com>
Acked-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: NUma Shankar <uma.shankar@intel.com>
Reviewed-by: NRamalingam C <ramalingam.c@intel.com>
Tested-by: NKarthik B S <karthik.b.s@intel.com>
Signed-off-by: NAnshuman Gupta <anshuman.gupta@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210111081120.28417-14-anshuman.gupta@intel.com

include/drm/drm_hdcp.h

@@ -101,11 +101,11 @@
 
 /* Following Macros take a byte at a time for bit(s) masking */
 /*
- * TODO: This has to be changed for DP MST, as multiple stream on
- * same port is possible.
- * For HDCP2.2 on HDMI and DP SST this value is always 1.
+ * TODO: HDCP_2_2_MAX_CONTENT_STREAMS_CNT is based upon actual
+ * H/W MST streams capacity.
+ * This required to be moved out to platform specific header.
  */
-#define HDCP_2_2_MAX_CONTENT_STREAMS_CNT	1
+#define HDCP_2_2_MAX_CONTENT_STREAMS_CNT	4
 #define HDCP_2_2_TXCAP_MASK_LEN			2
 #define HDCP_2_2_RXCAPS_LEN			3
 #define HDCP_2_2_RX_REPEATER(x)			((x) & BIT(0))