Can you get a dump of the SGTL5000 codec registers?

[IanCraig]

Hi

On my new iMX6Quad board I'm having issues getting the SGTL5000 audio codec to work. What is happening is the codec is getting initialised and the I2S clock is getting turned on at the end of initialisation but the clock turns off a few milliseconds later. I want to try and get a dump of the code registers after this point to see if the chip has been reset for some reason (supplies are fine),

I have taken a trace of the I2C traffic and this looks ok. The only thing I have noticed is if you run aplay once the system is up the top two bits of register CHIP_ADCDAC_CTRL are set. These indicate "Volume Busy DAC Right & Left". I have a reference working system and these bits are never set.

I have tried "cat /sys/devices/soc0/sound.17/HiFi/codec_reg" but get nothing back. I have also tried this via debugFS with the same result. Is there any other way to dump these registers?

Thanks

[abhijeet_ghodga]

Hi,

I am at a similar problem and want to modify the I2C registers of SGTL.

I have seen the initialized values using the registers file in regmap, but I want to change the value of one of the register.

The Linux OS, I am working on, does not have i2c-tools, hence no command like i2cset which can do this job. Any alternative way of setting the registers of SGTL5000?

Best,

Abhijeet

[fabio_estevam · Accepted solution]

Ian,

You can use regmap for such purpose.

These are the commands I do on a mx53qsb running kernel 4.0:

root@freescale /$ mount -t debugfs none /sys/kernel/debug/
root@freescale /$ cat /sys/kernel/debug/regmap/1-000a/registers
000: a011
002: 0060
004: 0008
006: 0080
00a: 0010
00e: 020c
010: 3c3c
014: 015f
020: 0000
022: 1818
024: 0022
026: 0068
028: 01f0
02a: 0000
02c: 0320
02e: 0e0e
030: 5260
032: 5000
034: 0000
036: 0017
03a: 0000
03c: 0000
100: 0000
102: 0000
104: 0040
106: 051f
108: 0000
10a: 0040
10c: 0000
10e: 0000
110: 0000
116: 002f
118: 002f
11a: 002f
11c: 002f
11e: 002f
120: 8000
122: 0000
124: 0510
126: 1473
128: 0028
12a: 0050
12c: 0000
12e: 0000
130: 0000
132: 0000
134: 0000
136: 0000
138: 0000

13a: 0000

[IanCraig]

Hi guys

Thanks fro the help. Managed to get the registers using regmap. Now to see if this helps in debugging my problem.

cheers

Ian

[fabio_estevam]

Hi Ian,

Thanks for the feedback.

Could you please mark the answer as 'correct answer'?

Thanks

[alejandrolozan1]

Hi,

You can use the -f option in i2cdump, i2cset to bypass the check on whether the device is in use by the kernel if you are running with root permissions.  For example:

'i2cdump -f -y -r 0-0xff 0 {your_device_address}'

Best Regards,

Alejandro