Re: writing an alsa driver

From: Michele Curti <michele.curti@gmail.com>
To: Vinod Koul <vinod.koul@intel.com>
Cc: Luka Karinja <luka.karinja@gmail.com>,
	Takashi Iwai <tiwai@suse.de>,
	ao2@ao2.it, alsa-devel@alsa-project.org,
	Liam Girdwood <liam.r.girdwood@linux.intel.com>,
	"Nikula, Jarkko" <jarkko.nikula@intel.com>,
	Bard Liao <bardliao@realtek.com>
Subject: Re: writing an alsa driver
Date: Thu, 3 Mar 2016 12:11:10 +0100	[thread overview]
Message-ID: <20160303111110.GA13202@acervm> (raw)
In-Reply-To: <20150625032407.GQ19530@localhost>

Hi Vinod,

On Thu, Jun 25, 2015 at 08:54:07AM +0530, Vinod Koul wrote:
> > [    2.700468] sst-mfld-platform sst-mfld-platform: Slot control: codec_in rx deinterleaver codec_in1_1 doesn't have DAPM widget!!!
> this is unexpected, I will check on this
> 
> > ...
> > [    7.970937] intel_sst_acpi 80860F28:00: Wait timed-out condition:0x0, msg_id:0x1 fw_state 0x3
> > [    7.970964] intel_sst_acpi 80860F28:00: fw returned err -16
> Yes this is a problem, which FW are you using
> 

I have a question regarding the FW timeout, but since it has been a long
time since last email, let me summarize the thread..

I tried to get sound working on an Asus X205TA laptop so, as far as I
understood, 3 things are needed in the ASoC world:
1. codec driver
2. platform driver
3. machine driver

1. codec driver (patch 0001 at [1])

It seems that the codec is a Relatek RT5648, and in kernel there is no
driver for it, but since it has the same product Id of the RT5645
(0x6308) I simply added an I2C and an ACPI match to the RT5645 codec
driver.

2. platform driver (patch 0002 at [1])

Used the sst-mfld-platform one (under sound/soc/intel/atom/sst), changing
the .acpi_ipc_irq_index from 5 to 0 because the DSP interrupt order in
the ACPI DSDT table of this laptop is different from the "normal" (see
line 3745 of dsdt.dsl at [2]).

$ cat /proc/interrupts | grep sst
            CPU0       CPU1       CPU2       CPU3       
   1:         24          0          0          0   IO-APIC   29-fasteoi   intel_sst_driver

Used the SSP0 version of the ADSP firmware (found at [3]), beacuse the
mainline FW uses the SSP2 port but this laptop has an atom Z3735F which
has only two SSP ports.

3. machine driver (patch 0003 at [1])

It's a copy-paste of sound/soc/intel/boards/bytcr_rt5651.c, but using
SSP0 instead of SSP2 and rt5645 instead of rt5651.

So, applying the three patches to the mainline linux kernel the sound
card shows up (aplay -l finds it) and at boot I got these errors:

[    4.378238] sst-mfld-platform sst-mfld-platform: Slot control: codec_out tx interleaver slot 0 doesn't have DAPM widget!!!
[    4.381301] sst-mfld-platform sst-mfld-platform: Slot control: codec_out tx interleaver slot 1 doesn't have DAPM widget!!!
[    4.384307] sst-mfld-platform sst-mfld-platform: Slot control: codec_out tx interleaver slot 2 doesn't have DAPM widget!!!
[    4.387276] sst-mfld-platform sst-mfld-platform: Slot control: codec_out tx interleaver slot 3 doesn't have DAPM widget!!!
[    4.390229] sst-mfld-platform sst-mfld-platform: Slot control: codec_in rx deinterleaver codec_in0_0 doesn't have DAPM widget!!!
[    4.390249] sst-mfld-platform sst-mfld-platform: Slot control: codec_in rx deinterleaver codec_in0_1 doesn't have DAPM widget!!!
[    4.390268] sst-mfld-platform sst-mfld-platform: Slot control: codec_in rx deinterleaver codec_in1_0 doesn't have DAPM widget!!!
[    4.390286] sst-mfld-platform sst-mfld-platform: Slot control: codec_in rx deinterleaver codec_in1_1 doesn't have DAPM widget!!!

About a minute of these errors:

[   62.894026] intel_sst_acpi 80860F28:00: Wait timed-out condition:0x0, msg_id:0x2 fw_state 0x3
[   62.903888] intel_sst_acpi 80860F28:00: fw returned err -16

And, when I play some audio, these ones:

[  102.350606]  Audio Port: ASoC: no backend DAIs enabled for Audio Port

Full dmesg at [4].

And, finally, the question: it is possible that the firmware timeout is
due to a missing alsa audio path and not to a fw problem?

Thanks,
Michele

[1] https://github.com/michelecurti/x205ta/tree/master/sound-patches
[2] https://github.com/michelecurti/x205ta/tree/master/acpi-tables
[3] https://git.kernel.org/cgit/linux/kernel/git/vkoul/firmware.git/commit/?h=byt
[4] http://pastebin.com/XAQZUvkM