On 11/28/23 09:00, Krzysztof Kozlowski wrote: > 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 > Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> > > --- > > This is an entirely different approach than my previous try here: > https://lore.kernel.org/all/20231025144601.268645-1-krzysztof.kozlowski@xxxxxxxxxx/ > --- > drivers/soundwire/qcom.c | 22 ++++++++++++++++++++++ > 1 file changed, 22 insertions(+) > > diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c > index 412b8e663a0a..57943724f0eb 100644 > --- a/drivers/soundwire/qcom.c > +++ b/drivers/soundwire/qcom.c > @@ -920,6 +920,18 @@ 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) > { > @@ -1078,6 +1090,7 @@ 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, nit-pick: read_prop() literally means "read platform properties". The functionality implemented in this callback looks more like an initialization done in a probe, no? > .xfer_msg = qcom_swrm_xfer_msg, > .pre_bank_switch = qcom_swrm_pre_bank_switch, > .post_bank_switch = qcom_swrm_post_bank_switch, > @@ -1196,6 +1209,15 @@ 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) { just realizing this now, are you sure the 'port_lock' is the proper means to protecting the stream->master_list? I don't see this used anywhere else in stream.c. I think you need to use bus_lock. > + /* > + * 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;