Re: [PATCH v5 2/2] ASoC: cs35l41: Read System Name from ACPI _SUB to identify firmware

From: Pierre-Louis Bossart
Date: Thu Jun 30 2022 - 15:50:23 EST




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;