Ad5529r driver

[jansunil]

PR Description

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PR Type

• Bug fix (a change that fixes an issue)
• New feature (a change that adds new functionality)
• Breaking change (a change that affects other repos or cause CIs to fail)

PR Checklist

• I have conducted a self-review of my own code changes
• I have compiled my changes, including the documentation
• I have tested the changes on the relevant hardware
• I have updated the documentation outside this repo accordingly
• I have provided links for the relevant upstream lore

[nunojsa]

Here it goes my first pass! Make sure to also pass this though AI

One more fundamental observation! This only supports raw writes which does bring too much... Can we at least have support for scale (and possibly offset if there is one)?

[jansunil]

changelog:

Added Scale and offset implementation
Added reset framework implementation with
Regmap Improvements with regmap access tables, removed lengthly functions
Remove limit checks wherever not needed
Added proper buffer alignment for the SPI tx and Rx buffers
Used memcpy to prepare the data buffers for SPI transactions
Dev_info -> dev_dbg() during probe success message
Removed mutex lock within the driver
Remove additional blank lines and redundant else statements
Made updates to devicetree and iio documentation as per driver updates
Corrected typo in SPI mode information in the devicetree documentaiton

[gastmaier]

llm: https://github.com/analogdevicesinc/linux/actions/runs/24329334842

[nunojsa]

I would really double check the regmap stuff. Im now wondering why we need the custom bus? We might be able to just use custom spi bus with 8 and 16 bit configs

[jansunil]

Changelog:

1. Simplified regmap 8 and 16 bit to use the standard regmap-spi
2. For 16 bit registers, directly pass the addr + 1 to the regmap bus (thereby handling decremental mode of addressing), so that the custom regmap API can be removed.
3. Updated documentation reflecting standard regmap-spi implementation

[nunojsa]

For the code, I think we can just send this upstream. But take care about the 12 vs 16 bits variants. It needs better justification, likely in the commit message about why we need two compatibles. I mean, if can just add the second datasheet link, then it becomes clear

[jansunil]

Changelog:

1. Remove tx and rx buffers from the ad5529r_state
2. Modify to one liner functions for ad5529r_debugfs_reg_read() and ad5529r_debugfs_reg_write()
3. Return regmap_write() directly in the ad5529r_reset()
4. Remove extra lines wherever applicable
5. Directly pass register address in the IIO_CHAN_INFO_RAW write function.
6. Remove necessity of two compatibles.
7. Detect connected hardware based on the product ID L value

[jansunil]

Changelog:

1. Remove unused includes and added whatever was missing
2. Removed unused type field and used static define for number of channels
3. Removed redundant dev_dbg() from the probe function
4. Added Software reset as a fallback when there is no Reset GPIO
5. Simplified scale calculation using IIO_VAL_FRACTIONAL_LOG2
6. Fixed reset function issues by removing redundant return

[nunojsa]

Alright, AFAICT go ahead and send this upstream

[jansunil]

Rebased branch with mirror_ci/jic23/iio/testing

[jansunil]

Rebased branch with mirror_ci/jic23/iio/testing, get rid of the CI deploy commit

[jansunil]

Upstream change requests:

1. Changed from single adi,ad5529r to variant-specific compatibles
2. Added information about clear, alarm, tg1,tg2,tg3 GPIOs and mux out in the devicetree binding
3. Made hvss-supply optional (only needed for bipolar ranges)
4. Added per channel child node support with Channel-specific adi,output-range-microvolt property
5. Simplified by using device tree compatible strings instead of reading product ID
6. Removed many unused register definitions, keeping only essential ones
7. Use reg stride and make the reaadable ranges table simpler for 16 bits
8. Added IIO_CHAN_INFO_OFFSET for proper voltage calculation, after the range addition
9. ad5529r_parse_channel_ranges() for per-channel configuration
10. Reorganized includes in alphabetical order, removed unused macros
11. Stick to 80 column
12. Remove the driver documentation ad5529r.rst, as it does not seem to hold much information.

[nunojsa]

use device_properties. It is preferred over OF. Also there are _scoped() versions so that you don't have to care about _put()

[nunojsa]

Do we include any address we should not read in the above ranges? I understand the stride config and that will prevent reading in invalid values. I also assume that for this to work all 16bit addresses are indeed multiple of 2?