soundwire: qcom: allow multi-link on newer devices

Newer Qualcomm SoCs like X1E80100 might come with four speakers spread
over two Soundwire controllers, thus they need a multi-link Soundwire
stream runtime.

Cc: Mark Brown <broonie@kernel.org>
Cc: alsa-devel@alsa-project.org
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20240405144141.47217-1-krzysztof.kozlowski@linaro.orgSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/soundwire/qcom.c

@@ -905,6 +905,18 @@ static int qcom_swrm_init(struct qcom_swrm_ctrl *ctrl)
 	return 0;
 }
 
+static int qcom_swrm_read_prop(struct sdw_bus *bus)
+{
+	struct qcom_swrm_ctrl *ctrl = to_qcom_sdw(bus);
+
+	if (ctrl->version >= SWRM_VERSION_2_0_0) {
+		bus->multi_link = true;
+		bus->hw_sync_min_links = 3;
+	}
+
+	return 0;
+}
+
 static enum sdw_command_response qcom_swrm_xfer_msg(struct sdw_bus *bus,
 						    struct sdw_msg *msg)
 {
@@ -1056,6 +1068,7 @@ static const struct sdw_master_port_ops qcom_swrm_port_ops = {
 };
 
 static const struct sdw_master_ops qcom_swrm_ops = {
+	.read_prop = qcom_swrm_read_prop,
 	.xfer_msg = qcom_swrm_xfer_msg,
 	.pre_bank_switch = qcom_swrm_pre_bank_switch,
 };
@@ -1173,6 +1186,15 @@ static int qcom_swrm_stream_alloc_ports(struct qcom_swrm_ctrl *ctrl,
 
 	mutex_lock(&ctrl->port_lock);
 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
+		/*
+		 * For streams with multiple masters:
+		 * Allocate ports only for devices connected to this master.
+		 * Such devices will have ports allocated by their own master
+		 * and its qcom_swrm_stream_alloc_ports() call.
+		 */
+		if (ctrl->bus.id != m_rt->bus->id)
+			continue;
+
 		if (m_rt->direction == SDW_DATA_DIR_RX) {
 			maxport = ctrl->num_dout_ports;
 			port_mask = &ctrl->dout_port_mask;