iwlwifi: adding MIMO3 support in rate scaling

Separated the MIMO tpt matrix into MIMO2 and MIMO3, adding MIMO3 support
in rate scaling algorithm. If the device support 3x3, then utilize all
three antenna (A/B/C) for tx to improve throughput.

Adding rs_switch_to_mimo3() function to allow switch to mimo3 modulation
mode from other modes(legacy/siso/mimo2). Adding rs_move_mimo3_to_other()
function to allow switch from mimo3 modulation mode to either siso or mimo2;
also support toggle between SGI and NGI.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/iwl-agn-rs.h

@@ -241,6 +241,7 @@ enum {
 #define IWL_LEGACY_SWITCH_MIMO2_AB      3
 #define IWL_LEGACY_SWITCH_MIMO2_AC      4
 #define IWL_LEGACY_SWITCH_MIMO2_BC      5
+#define IWL_LEGACY_SWITCH_MIMO3_ABC     6
 
 /* possible actions when in siso mode */
 #define IWL_SISO_SWITCH_ANTENNA1        0
@@ -249,6 +250,8 @@ enum {
 #define IWL_SISO_SWITCH_MIMO2_AC        3
 #define IWL_SISO_SWITCH_MIMO2_BC        4
 #define IWL_SISO_SWITCH_GI              5
+#define IWL_SISO_SWITCH_MIMO3_ABC       6
+
 
 /* possible actions when in mimo mode */
 #define IWL_MIMO2_SWITCH_ANTENNA1       0
@@ -257,6 +260,21 @@ enum {
 #define IWL_MIMO2_SWITCH_SISO_B         3
 #define IWL_MIMO2_SWITCH_SISO_C         4
 #define IWL_MIMO2_SWITCH_GI             5
+#define IWL_MIMO2_SWITCH_MIMO3_ABC      6
+
+
+/* possible actions when in mimo3 mode */
+#define IWL_MIMO3_SWITCH_ANTENNA1       0
+#define IWL_MIMO3_SWITCH_ANTENNA2       1
+#define IWL_MIMO3_SWITCH_SISO_A         2
+#define IWL_MIMO3_SWITCH_SISO_B         3
+#define IWL_MIMO3_SWITCH_SISO_C         4
+#define IWL_MIMO3_SWITCH_MIMO2_AB       5
+#define IWL_MIMO3_SWITCH_MIMO2_AC       6
+#define IWL_MIMO3_SWITCH_MIMO2_BC       7
+#define IWL_MIMO3_SWITCH_GI             8
+
+
 
 /*FIXME:RS:add possible actions for MIMO3*/