Re: [PATCH 3/3] soundwire: bus_type: add sdw_master_device support

On 11-05-20, 14:00, Pierre-Louis Bossart wrote:

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• md = &bus->md;
• md->dev.bus = &sdw_bus_type;
• md->dev.type = &sdw_master_type;
• md->dev.parent = parent;
• md->dev.of_node = parent->of_node;
• md->dev.fwnode = fwnode;
• md->dev.dma_mask = parent->dma_mask;
• dev_set_name(&md->dev, "sdw-master-%d", bus->link_id);

This give nice sdw-master-0. In DT this comes from reg property. I dont seem to recall if the ACPI/Disco spec treats link_id as unique across the system, can you check that please, if not we would need to update this.

Table 3 in the Disco for Soundwire 1.0 spec: "all LinkID values are relative to the immediate parent Device."

There isn't any known implementation with more than one controller.

But then it can come in "future" right. So lets try to make it future proof by not using the link_id (we can expose that as a sysfs if people want to know). So a global unique id needs to allocated (hint: idr or equivalent) and used as master_id

Thanks