[alsa-devel] [PATCH v1 2/9] ASoC: Intel: Skylake: Add entry in sst_acpi_mach for HDA codecs

[Ughreja, Rakesh A]

>-----Original Message-----
>From: Pierre-Louis Bossart [mailto:pierre-louis.bossart at linux.intel.com]
>Sent: Friday, February 23, 2018 10:13 PM
>To: Ughreja, Rakesh A <rakesh.a.ughreja at intel.com>; alsa-devel at alsa-
>project.org; broonie at kernel.org; tiwai at suse.de;
>liam.r.girdwood at linux.intel.com
>Cc: Koul, Vinod <vinod.koul at intel.com>; Patches Audio
><patches.audio at intel.com>
>Subject: Re: [PATCH v1 2/9] ASoC: Intel: Skylake: Add entry in sst_acpi_mach for
>HDA codecs
>
>On 2/23/18 2:12 AM, Rakesh Ughreja wrote:
>> When no I2S based codec entries are found in the BIOS, check if there are
>> any HDA codecs detected on the bus. If there are two (i.e. iDisp + HDA)
>> HDA codecs found on the bus, load the HDA machine driver.
>
>What if you have a headless device with no codec, that means no HDMI
>support? Why is this restriction necessary?

This machine driver handles HDA and iDisp combination only.

If you want to handle only iDisp or only HDA or more than one HDA
different machine driver needs to be written or this machine
driver needs to be enhanced.

Machine driver has BE DAI link information and so it is specific to those
many devices for a given platform.

>
>>
>> Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja at intel.com>
>> ---
>>   sound/soc/intel/skylake/skl.c | 59
>+++++++++++++++++++++++++++++++++++++++----
>>   1 file changed, 54 insertions(+), 5 deletions(-)
>>
>> diff --git a/sound/soc/intel/skylake/skl.c b/sound/soc/intel/skylake/skl.c
>> index f948f29..ac64416 100644
>> --- a/sound/soc/intel/skylake/skl.c
>> +++ b/sound/soc/intel/skylake/skl.c
>> @@ -442,6 +442,24 @@ static struct skl_ssp_clk skl_ssp_clks[] = {
>>   						{.name = "ssp5_sclkfs"},
>>   };
>>
>> +static struct snd_soc_acpi_mach *skl_find_hda_machine(struct skl *skl,
>> +					struct snd_soc_acpi_mach
>*machines)
>> +{
>> +
>> +	struct snd_soc_acpi_mach *mach;
>> +	struct hdac_bus *bus = skl_to_bus(skl);
>> +
>> +	/* check if we have two HDA codecs */
>> +	if (hweight_long(bus->codec_mask) != 2)
>> +		return NULL;
>> +
>> +	for (mach = machines; mach->id[0]; mach++) {
>> +		if (!strcmp(mach->id, "HDA_GEN"))
>> +			return mach;
>> +	}
>
>that's not really testing if there are actual HDaudio devices, is this
>loop just there to point to a firmware file?

There is a check for number of codecs in the previous line.
By default the iDisp codec would always be present so the check
is for count 2.

>
>> +	return NULL;
>> +}
>> +
>>   static int skl_find_machine(struct skl *skl, void *driver_data)
>>   {
>>   	struct hdac_bus *bus = skl_to_bus(skl);
>> @@ -450,8 +468,12 @@ static int skl_find_machine(struct skl *skl, void
>*driver_data)
>>
>>   	mach = snd_soc_acpi_find_machine(mach);
>>   	if (mach == NULL) {
>> -		dev_err(bus->dev, "No matching machine driver found\n");
>> -		return -ENODEV;
>> +		dev_dbg(bus->dev, "No matching I2S machine driver found\n");
>> +		mach = skl_find_hda_machine(skl, driver_data);
>> +		if (mach == NULL) {
>> +			dev_err(bus->dev, "No matching machine driver
>found\n");
>> +			return -ENODEV;
>> +		}
>>   	}
>>
>>   	skl->mach = mach;
>> @@ -466,8 +488,9 @@ static int skl_find_machine(struct skl *skl, void
>*driver_data)
>>
>>   static int skl_machine_device_register(struct skl *skl)
>>   {
>> -	struct hdac_bus *bus = skl_to_bus(skl);
>>   	struct snd_soc_acpi_mach *mach = skl->mach;
>> +	struct hdac_bus *bus = skl_to_bus(skl);
>> +	struct skl_machine_pdata *pdata;
>>   	struct platform_device *pdev;
>>   	int ret;
>>
>> @@ -484,8 +507,11 @@ static int skl_machine_device_register(struct skl *skl)
>>   		return -EIO;
>>   	}
>>
>> -	if (mach->pdata)
>> +	if (mach->pdata) {
>> +		pdata = (struct skl_machine_pdata *)mach->pdata;
>> +		pdata->platform = dev_name(bus->dev);
>>   		dev_set_drvdata(&pdev->dev, mach->pdata);
>> +	}
>>
>>   	skl->i2s_dev = pdev;
>>
>> @@ -1030,6 +1056,14 @@ static struct snd_soc_acpi_mach sst_skl_devdata[]
>= {
>>   		.quirk_data = &skl_codecs,
>>   		.pdata = &skl_dmic_data
>>   	},
>> +	{
>> +		.id = "HDA_GEN",
>> +		.drv_name = "skl_hda_generic",
>> +		.fw_filename = "intel/dsp_fw_release.bin",
>> +		.machine_quirk = NULL,
>> +		.quirk_data = NULL,
>> +		.pdata = &cnl_pdata,
>
>this is odd, the cnl_pdata says the topology_pcm is used, I thought this
>was not applicable for SKL/KBL. Or put differently, why is this used for
>the hda case only?

This flag is used for using the topology framework for creating the 
FE DAIs and DAI Links. The other I2S machine drivers which are
up-streamed some time back don't have support for creating
DAIs and DAI Links from topology file. Based on your comments
given in the RFC, I have added this support for HDA machine drivers
even for SKL, KBL also.

Regards,
Rakesh