Re: [alsa-devel] [PATCH v2 2/4] soundwire: core: add device tree support for slave devices

@@ -35,6 +36,7 @@ static int sdw_slave_add(struct sdw_bus *bus,

slave->dev.release = sdw_slave_release; slave->dev.bus = &sdw_bus_type;

• slave->dev.of_node = of_node_get(to_of_node(fwnode));

shouldn't this protected by #if IS_ENABLED(CONFIG_OF) ?

slave->bus = bus; slave->status = SDW_SLAVE_UNATTACHED; slave->dev_num = 0; @@ -112,3 +114,48 @@ int sdw_acpi_find_slaves(struct sdw_bus *bus) }

#endif

+/*

• • sdw_of_find_slaves() - Find Slave devices in master device tree node
• • @bus: SDW bus instance
• • Scans Master DT node for SDW child Slave devices and registers it.
• */

+int sdw_of_find_slaves(struct sdw_bus *bus) +{

• struct device *dev = bus->dev;
• struct device_node *node;
• for_each_child_of_node(bus->dev->of_node, node) {

• struct sdw_slave_id id;
  

• const char *compat = NULL;
  

• int unique_id, ret;
  

• int ver, mfg_id, part_id, class_id;
  

• compat = of_get_property(node, "compatible", NULL);
  

• if (!compat)
  

• 	continue;
  

• ret = sscanf(compat, "sdw%x,%x,%x,%x",
  

• 	     &ver, &mfg_id, &part_id, &class_id);
  

• if (ret != 4) {
  

• 	dev_err(dev, "Manf ID & Product code not found %s\n",
  

• 		compat);
  

• 	continue;
  

• }
  

• ret = of_property_read_u32(node, "sdw-instance-id", &unique_id);
  

• if (ret) {
  

• 	dev_err(dev, "Instance id not found:%d\n", ret);
  

• 	continue;
  

I am confused here. If you have two identical devices on the same link, isn't this property required and that should be a real error instead of a continue?

• }
  

• id.sdw_version = ver - 0xF;
  

maybe a comment in the code would help to make the encoding self-explanatory, as you did in the DT bindings

Version number '0x10' represents SoundWire 1.0 Version number '0x11' represents SoundWire 1.1

• id.unique_id = unique_id;
  

• id.mfg_id = mfg_id;
  

• id.part_id = part_id;
  

• id.class_id = class_id;
  

• sdw_slave_add(bus, &id, of_fwnode_handle(node));
  

• }
• return 0;

+}