[PATCH v6 0/4] iio: chemical: Add Senseair Sunrise CO2 sensor

[Jacopo Mondi <jacopo+renesas@jmondi.org>]

The driver supports continuous reads of temperature and CO2 concentration
through two dedicated IIO channels. It also supports calibration and error
inspection through the concentration channel ext_info.


v5->v6:
- Apply style fixes from Andy
- Apply Jonathan suggestion and reduce sysfs attribute critical section
- Address Peter's comments on the regmap ops:
  - Do not use SMBUS_QUICK as it's supported by few adapters
  - Make protocol mangling optional
  - Insert a 'wake up' delay between the wake up message and the transaction
  - Check for the adapter's required functionalities

v4->v5:
- Address Andy's style comments
- Use custom regmap operations that performs unlocked access to the I2C bus
- Lock the I2C segment during the driver's read/write functions
- Add kernel version to the driver's ABI documentation
- Add scale for the in_concentration_co2 channel
- Document in_concentration_co2_scale
- Add MAINTAINERS entry for sysfs-bus-iio-chemical-sunrise-co2

v3->v4
 - Rebased on v5.14
 - Remove unneeded Kconfig symbol dependencies
 - Remove unused header inclusion
 - Lock access to calibration and error status
 - Fix temperature scale
 - Fix for_each_set_bit()
 - Drop a few fields from driver's main structure
 - Lock the 'wakeup' session with an additional mutex
 - Disable regmap locking as the access to the i2c bus is now externally locked
 - Rework the calibration attributes defintion: one attribute per calibration
   mode
 - Make 'error_status' attributes SHARED_BY_ALL
 - Replace regmap_read_poll_timeout() with read_poll_timeout() to use
   the driver's byte read function that performs the proper chip 'wakeup'.
   It used to work with the previous version too, a few spurious NAK apart but
   this seems cleaner and allows to relax the sleep time
 - Update ABI documentation according to the new attributes layout
 - Remove label from bindings doc

v2->v3:
- [1/3]
 - Fix syntax error reported by dt_binding_check
   The device node label in the example cannot contain '-'
 - Add 'Typically' to the gpios polarities description

- [2/3]
 - As suggested by Andy:
   - depends on OF, SYSFS; select REGMAP_I2C
   - Fix style issues:
     - span over 80 cols where appropriate
     - remove , in last entries of all arrays
     - use for_each_set_bit in sunrise_error_status_read()
     - minor style issues (brakets, empty lines, wording)

v1->v2:
- Add ABI documentation in [3/3]
- [1/3]
  - Address Rob's comments on missing maxItem and add device node label
  - Do not change the pin's polarity description as suggested by Andy due to
    conflicting suggestions
- [2/3]
  - Expand Kconfig symbol name and change driver's name as suggested by Andy
  - Use regmap instead of raw smbus calls as suggested by Andy
  - Take into account minor style comments from Andy
  - Install channel's ext_info to support calibration triggering and enumerate
    calibration modes and error status
  - Matt suggested to use sysfs attributes, but I found the per-channel
    attributes more appropriate. Hope this is good as well.

Jacopo Mondi (4):
  dt-bindings: iio: chemical: Document senseair,sunrise CO2 sensor
  iio: ABI: docs: Document Senseair Sunrise ABI
  iio: chemical: Add Senseair Sunrise 006-0-007 driver
  iio: ABI: Document in_concentration_co2_scale

 Documentation/ABI/testing/sysfs-bus-iio       |   1 +
 .../sysfs-bus-iio-chemical-sunrise-co2        |  38 ++
 .../iio/chemical/senseair,sunrise.yaml        |  55 ++
 .../devicetree/bindings/vendor-prefixes.yaml  |   2 +
 MAINTAINERS                                   |   7 +
 drivers/iio/chemical/Kconfig                  |  10 +
 drivers/iio/chemical/Makefile                 |   1 +
 drivers/iio/chemical/sunrise_co2.c            | 551 ++++++++++++++++++
 8 files changed, 665 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-chemical-sunrise-co2
 create mode 100644 Documentation/devicetree/bindings/iio/chemical/senseair,sunrise.yaml
 create mode 100644 drivers/iio/chemical/sunrise_co2.c

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2.32.0