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by Xavier_S
Thu Aug 22, 2019 9:45 pm
Forum: Device Tree
Topic: Set up GPIO clock from device tree
Replies: 17
Views: 6717

Re: Set up GPIO clock from device tree

It would be very helpful if you can provide a step by step procedure of achieving the frequency from the device tree, What I have done involves a device tree overlay PLUS a device driver. If you want to follow that way, the overlay itself is only the smaller part of what you have to do. You just ha...
by Xavier_S
Fri Aug 16, 2019 12:10 am
Forum: Device Tree
Topic: Set up GPIO clock from device tree
Replies: 17
Views: 6717

Re: Set up GPIO clock from device tree

Your life would be easier if you elected to feed your PLL with a 19.2 MHz submultiple, and not the oscillator frequency itself. The reason is that outputting the native oscillator frequency from pin GPIO4 seems to be no easy task (if only possible). On the other hand, getting 19.2 MHz ÷ 2 (9.6 MHz),...
by Xavier_S
Mon Jul 08, 2019 5:39 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: The I2S sound thread.
Replies: 925
Views: 453797

Re: STICKY: The I2S sound thread.

In your codec_port you have a typo: remote-endpoint = <&cpu_endpoin$ instead of remote-endpoint = <&cpu_endpoint>;.
Is it just in your post, or in your overlay as well?
by Xavier_S
Sun Jul 07, 2019 11:06 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: The I2S sound thread.
Replies: 925
Views: 453797

Re: STICKY: The I2S sound thread.

Is it wrong compared to the solution on the link you gave ? If you read carefully PhilE's answer to this post: https://lb.raspberrypi.org/forums/viewtopic.php?t=136988 , you will see that it is not the way to go... I can't check it works since I have no scope, but my meter says 1.6 VDC which could ...
by Xavier_S
Sun Jul 07, 2019 4:09 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: The I2S sound thread.
Replies: 925
Views: 453797

Re: STICKY: The I2S sound thread.

1- The PCM1690 needs to get its BCK and LRCK from the I2S. Therefore for each one of these signals, it is an I2S clock slave, and your driver must be configured accordingly. 2- When you configure your DAI Link so that your codec is a clock slave, then automatically the other end of the link is suppo...
by Xavier_S
Fri Apr 12, 2019 5:36 pm
Forum: Device Tree
Topic: Set up GPIO clock from device tree
Replies: 17
Views: 6717

Re: Set up GPIO clock from device tree

Thanks PhilE for your answer, which helped me go in the right direction. At last I got it to work. What I was missing was the clk_prepare(), which I forgot to call after devm_clk_get() and clk_set_rate(). From my experiments I made a couple of observations I found interesting to share here, as exten...
by Xavier_S
Mon Mar 18, 2019 3:39 pm
Forum: Device Tree
Topic: Set up GPIO clock from device tree
Replies: 17
Views: 6717

Re: Set up GPIO clock from device tree

Hello, I am resurrecting this old thread because I need to set up a GPIO clock from the device tree, and none of the operations described above have worked for me so far. I am building an I2S codec (which works), controlled and configured via I2C (which also works). My I2S interface already has its ...
by Xavier_S
Thu Nov 22, 2018 11:55 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: The I2S sound thread.
Replies: 925
Views: 453797

Re: STICKY: The I2S sound thread.

Hello Hias – finally I figured out by myself. In my snd_soc_dai_driver I just had to create a .capture along with my .playback – which I had not done until now. Then I just routed .playback to .capture and voilà, it works! It is that simple. wm0010.c was a very good example for that. Have a good day...
by Xavier_S
Wed Nov 21, 2018 10:53 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: The I2S sound thread.
Replies: 925
Views: 453797

Re: STICKY: The I2S sound thread.

Ok Hias, thank you. Now comes the question of routing. My Clock Master is declared as a soundcard + codec. Therefore the codec part's snd_soc_codec_driver needs a .component_driver with .dapm_widgets and .dapm_routes. However my device, being just a clock source, has no physical contact with the i2s...
by Xavier_S
Tue Nov 20, 2018 1:28 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: The I2S sound thread.
Replies: 925
Views: 453797

Re: STICKY: The I2S sound thread.

Hello Hias, Yet another question, before I put everything on the launchpad. My soundcard driver now sits between the bcm2835 and pcm512x. It has no .controls by itself, however it has to relay all pcm512x kcontrols so that they are all made available to alsamixer. In your rpi-cirrus driver it looks ...
by Xavier_S
Sat Nov 17, 2018 2:36 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: The I2S sound thread.
Replies: 925
Views: 453797

Re: STICKY: The I2S sound thread.

Thank you Hias for your very detailed response ! The codec-codec link is exactly what I was missing, I'm going to follow this path right now.
I'll keep you posted. Thanks again!

Xavier
by Xavier_S
Fri Nov 16, 2018 4:49 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: The I2S sound thread.
Replies: 925
Views: 453797

Re: STICKY: The I2S sound thread.

Hello, I am building an audio setup with an I2S DAC, where I need to be able to finely tune the I2S clock speed. Therefore I built an I2C-controlled clock source to act as an external I2S Clock Master, which I connected to the bit-clk and frame-clk lines. This clock source gives me the required freq...

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