On 6/30/22 14:34, Mark Brown wrote: > On Thu, Jun 30, 2022 at 01:35:05PM -0500, Pierre-Louis Bossart wrote: > >> It's my understanding that the _SUB method is optional, not required. It >> may be wise to plan for a fallback, e.g to use DMI quirks or other >> identifiers, no? > > Presumably the fallback would go into cs35l41_acpi_get_name()? That's what I had in mind, if this _SUB does not exist then you could use something else instead of returning -ENODATA; + sub = acpi_get_subsystem_id(handle); + if (IS_ERR(sub)) + return PTR_ERR(sub); + + cs35l41->dsp.system_name = sub;