[PATCH v2] soundwire: qcom: allow multi-link on newer devices

From: Krzysztof Kozlowski
Date: Fri Apr 05 2024 - 10:42:07 EST


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@xxxxxxxxxx>
Cc: alsa-devel@xxxxxxxxxxxxxxxx
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>

---

Changes in v2:
1. Only rebase (slightly different context)
---
drivers/soundwire/qcom.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)

diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c
index fb70afe64fcc..ce5cf3ecceb5 100644
--- a/drivers/soundwire/qcom.c
+++ b/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;
--
2.34.1