Re: [Sound-open-firmware] [PATCH v2 3/5] ASoC: SOF: Add DT DSP device support

From: Pierre-Louis Bossart
Date: Wed Aug 07 2019 - 11:22:16 EST



+static int sof_dt_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ const struct sof_dev_desc *desc;
+ /*TODO: create a generic snd_soc_xxx_mach */
+ struct snd_soc_acpi_mach *mach;

I wonder if you really need to use the same structures. For Intel we get
absolutely zero info from the firmware so rely on an ACPI codec ID as a
key to find information on which firmware and topology to use, and which
machine driver to load. You could have all this information in a DT blob?

Yes. I see your point. I will still need to make a generic structure for
snd_soc_acpi_mach so that everyone can use sof_nocodec_setup function.

Maybe something like this:

struct snd_soc_mach {
union {
struct snd_soc_acpi_mach acpi_mach;
struct snd_soc_of_mach of_mach;
}
};

and then change the prototype of sof_nocodec_setup.

Hi Pierre,

I fixed all the comments except the one above. Replacing snd_soc_acpi_mach
with a generic snd_soc_mach is not trivial task.

I wonder if it is acceptable to get the initial patches as they are
now and later switch to
generic ACPI/OF abstraction.

Asking this because for the moment on the i.MX side I have only
implemented no codec
version and we don't probe any of the machine drivers we have.

So, there is this only one member of snd_soc_acpi_mach that imx
version is making use of:

mach->drv_name = "sof-nocodec";

That's all.

I think the change as it is now is very clean and non-intrusive. Later
we will get options to
read firmware name and stuff from DT.

Anyhow, I don't think we can get rid of snd_dev_desc structure on
i.MX. This will be used
to store the information read from DT:

static struct sof_dev_desc sof_of_imx8qxp_desc = {
 .default_fw_path = "imx/sof",
 .default_tplg_path = "imx/sof-tplg",
 .nocodec_fw_filename = "sof-imx8.ri",
 .nocodec_tplg_filename = "sof-imx8-nocodec.tplg",
 .ops = &sof_imx8_ops,
};

For the moment we will only use the default values.

Yes, that's fine for now. If you don't have a real machine driver then there's nothing urgent to change.

Is the new version on GitHub?

Thanks
-Pierre