diff options
Diffstat (limited to 'drivers/soundwire/mipi_disco.c')
| -rw-r--r-- | drivers/soundwire/mipi_disco.c | 40 |
1 files changed, 39 insertions, 1 deletions
diff --git a/drivers/soundwire/mipi_disco.c b/drivers/soundwire/mipi_disco.c index 9d59f486edbe..65afb28ef8fa 100644 --- a/drivers/soundwire/mipi_disco.c +++ b/drivers/soundwire/mipi_disco.c @@ -366,6 +366,44 @@ static int sdw_slave_read_dpn(struct sdw_slave *slave, return 0; } +/* + * In MIPI DisCo spec for SoundWire, lane mapping for a slave device is done with + * mipi-sdw-lane-x-mapping properties, where x is 1..7, and the values for those + * properties are mipi-sdw-manager-lane-x or mipi-sdw-peripheral-link-y, where x + * is an integer between 1 to 7 if the lane is connected to a manager lane, y is a + * character between A to E if the lane is connected to another peripheral lane. + */ +int sdw_slave_read_lane_mapping(struct sdw_slave *slave) +{ + struct sdw_slave_prop *prop = &slave->prop; + struct device *dev = &slave->dev; + char prop_name[30]; + const char *prop_val; + size_t len; + int ret, i; + u8 lane; + + for (i = 0; i < SDW_MAX_LANES; i++) { + snprintf(prop_name, sizeof(prop_name), "mipi-sdw-lane-%d-mapping", i); + ret = device_property_read_string(dev, prop_name, &prop_val); + if (ret) + continue; + + len = strlen(prop_val); + if (len < 1) + return -EINVAL; + + /* The last character is enough to identify the connection */ + ret = kstrtou8(&prop_val[len - 1], 10, &lane); + if (ret) + return ret; + if (in_range(lane, 1, SDW_MAX_LANES - 1)) + prop->lane_maps[i] = lane; + } + return 0; +} +EXPORT_SYMBOL(sdw_slave_read_lane_mapping); + /** * sdw_slave_read_prop() - Read Slave properties * @slave: SDW Slave @@ -486,6 +524,6 @@ int sdw_slave_read_prop(struct sdw_slave *slave) sdw_slave_read_dpn(slave, prop->sink_dpn_prop, nval, prop->sink_ports, "sink"); - return 0; + return sdw_slave_read_lane_mapping(slave); } EXPORT_SYMBOL(sdw_slave_read_prop); |