Re: [PATCH v3] ASoC: dt-bindings: davinci-mcasp: convert McASP bindings to yaml schema

29 Nov 2021

      On 29/11/21 12:23 pm, Péter Ujfalusi wrote:
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On 26/11/2021 07:02, Jayesh Choudhary wrote:
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Convert the bindings for McASP controllers for TI SOCs
from txt to YAML schema.
Can you CC the sound/soc/ti/ maintainer next time, I have found this
patch in my Spam folder...
Okay. Also, I will add this file in the MAINTAINERS file under the 
heading 'TEXAS INSTRUMENTS ASoC DRIVERS'
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Adds additional properties 'clocks', 'clock-names', 'power-domains',
'#sound-dai-cells',
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'num-serializer'
Which use was removed by 1427e660b49e87cd842dba94158b0fc73030c17e
The dts file of arm SOCs is not updated and was generating an error in 
dtbs_check. I will remove this property.
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and 'port'
And what this "port" is?
The mcasp node in the file 'arch/arm/boot/dts/am335x-sl50.dts' has this 
as child node.
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which were not there in the txt file.
Most likely for a reason?
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Adds 'dmas' and 'dma-names' in the example which were not there in
the txt file.
Changes 'interrupts' and 'interrupt-names' from optional to
required properties.
My biggest problem with the davinci-mcasp-audio.txt is that it was done
in a wrong way and it just documented the pdata parameters as DT binding.
If we convert it to yaml, this is going to be 'written in stone'.
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Signed-off-by: Jayesh Choudhary j-choudhary@ti.com
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tdm-slots:

description?
I will add description.
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maxItems: 1

serial-dir:
description:
 A list of serializer configuration

 Entry is indication for serializer pin direction

 0 - Inactive, 1 - TX, 2 - RX

You should mention that _all_ AXR pins should be present in the array,
even if they are no in use.
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$ref: /schemas/types.yaml#/definitions/uint32-array
minItems: 1
maxItems: 16

a McASP could have up to 25 AXR pins...
Will update the description and the maximum.
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items:
 minimum: 0

 maximum: 2

 default: 0

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tx-num-evt:

description?
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maxItems: 1

rx-num-evt:

description?
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maxItems: 1

dismod:

description?
For the above three properties, is the description in the txt file 
sufficient?
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sram-size-playback:
maxItems: 1

should be dropped, not used
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sram-size-capture:
maxItems: 1

not used, please drop
Okay.
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interrupts:
minItems: 1
items:
 - description: TX FIFO interrupt

 - description: RX FIFO interrupt

The 'common' does not deserve a description?
Will add this.
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gpio-controller: true

"#gpio-cells":
const: 2

function-gpios:
maxItems: 1

This is not McASP property, it was an example on how to use a pin as
GPIO from the outside...
Okay. will remove function-gpios.
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clocks:
minItems: 1
maxItems: 3

clock-names:
minItems: 1
items:
 - const: fck

 - const: ahclkx

 - const: ahclkr

I can not find any use in the code for ahclkx/r?
Some arm SOCs had additional clocks in the DT nodes.
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+required:

compatible

reg

reg-names

dmas

dma-names

interrupts

interrupt-names

serial-dir

op-mode

tdm-slots

The last three is not needed if the McASP is used only as GPIO.
The dmas and interrupts should not be needed in this case, but I think
it is not taken care of atm.
The tdm-slots is ignored for DIT mode
These were mentioned in txt file as required.
In light of this new knowledge, I will remove 'serial-dir', 'op-mode' 
and 'tdm-slots'.
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