CS35L41 has a DSP which is able to run firmware, as well as a tuning file. Different systems may want to use different firmwares and tuning files, and some firmwares/tunings may not be compatible with other systems. To allow a system to select the correct fimware/tuning, we can read an _SUB from the ACPI. This _SUB can then be used to uniquely identify the system in the firmware/tuning file name.
Add a helper function which reads the _SUB, so this can be used by other parts in the future. Add support inside the CS35L41 ASoC driver to read this _SUB, and save it appropriately.
Stefan Binding (2): ACPI: utils: Add api to read _SUB from ACPI ASoC: cs35l41: Read System Name from ACPI _SUB to identify firmware
drivers/acpi/utils.c | 26 ++++++++++++++++++++++++++ include/linux/acpi.h | 8 ++++++++ sound/soc/codecs/cs35l41.c | 27 +++++++++++++++++++++++++++ 3 files changed, 61 insertions(+)