Re: [PATCH] ALSA: hda - Add new driver for HDA controllers listed via ACPI

On Thu, 15 May 2025 15:31:46 +0200, Daniel Dadap wrote:

Some systems expose HD-Audio controllers via objects in the ACPI tables which encapsulate the controller's interrupt and the base address for the HDA registers in an ACPI _CRS object, for example, as listed in this ACPI table dump excerpt:

    Device (HDA0)
    {
        Name (_HID, "NVDA2014")  // _HID: Hardware ID
        ...
        Name (_CRS, ResourceTemplate ()  // _CRS: Current Resource Settings
        {
            Memory32Fixed (ReadWrite,
                0x36078000,         // Address Base
                0x00008000,         // Address Length
                )
            Interrupt (ResourceConsumer, Level, ActiveHigh, Exclusive, ,, )
            {
                0x0000021E,
            }
        })
    }

Add support for HDA controllers discovered through ACPI, including support for some platforms which expose such HDA controllers on NVIDIA SoCs. This is done with a new driver which uses existing infrastructure for extracting resource information from _CRS objects and plumbs the parsed resource information through to the existing HDA infrastructure to enable HD-Audio functionality on such devices.

Although this driver is in the sound/pci/hda/ directory, it targets devices which are not actually enumerated on the PCI bus. This is because it depends upon the Intel "Azalia" infrastructure which has traditionally been used for PCI-based devices.

Signed-off-by: Daniel Dadap ddadap@nvidia.com

Thanks for the patch. The code looks fine. Just a nitpicking:

+static int __maybe_unused hda_acpi_suspend(struct device *dev)

....

+static int __maybe_unused hda_acpi_resume(struct device *dev)

The __maybe_unused is superfluous when you set up SYSTEM_SLEEP_PM_OPS() macro instead in the below:

+static const struct dev_pm_ops hda_acpi_pm = {

• SET_SYSTEM_SLEEP_PM_OPS(hda_acpi_suspend, hda_acpi_resume)

thanks,

Takashi