soundwire: subtract BRA columns in bandwidth calculation

When a BRA stream is running, we should subtract the columns that is
used by the BRA stream in bandwidth calculation.

Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>

Author: bardliao

drivers/soundwire/generic_bandwidth_allocation.c

@@ -567,6 +567,7 @@ static int sdw_compute_bus_params(struct sdw_bus *bus)
 	unsigned int curr_dr_freq = 0;
 	int i, l, clk_values, ret;
 	bool is_gear = false;
+	int available_col;
 	int m_lane = 0;
 	u32 *clk_buf;
 
@@ -609,7 +610,21 @@ static int sdw_compute_bus_params(struct sdw_bus *bus)
 
 		total_col = curr_dr_freq / mstr_prop->default_frame_rate / mstr_prop->default_row;
 
-		if (curr_dr_freq * (total_col - 1) >=
+		/*
+		 * available payload columns on lane 0:
+		 * - exclude control column 0
+		 * - if BPT is active, also exclude columns 1..bpt_hstop used by DP0
+		 */
+		if (bus->bpt_stream_refcount)
+			available_col = total_col - bus->bpt_hstop - 1;
+		else
+			available_col = total_col - 1;
+
+		if (available_col <= 0)
+			continue;
+
+		/* Keep formula consistent with sdw_select_row_col() */
+		if (curr_dr_freq * available_col >=
 		    bus->params.bandwidth * total_col)
 			break;