[PATCH v5 00/11] leds: pca995x: Minor fixes; reset, output-gain, error reporting and group brightness support

[Nora Schiffer <nora.schiffer@ew.tq-group.com>]

This series adds several new features to the PCA995x LED driver:

- Reset GPIO
- Output current configuration
- Error reporting via sysfs (short/open circuit)
- Group brightness control (modulating individual LED brightness with a
  second, chip-global PWM signal)

The series also includes a number of low-priority fixes:

- Prevent configuration of out-of-bounds LED indices on 16-channel variants
- Avoid fwnode leaks in error paths
- Finish initializing hardware before making LED devices visible to
  userspace

Changelog:

v5:
- Collect Reviewed-bys
- Limit fault detection to PCA9955B/PCA9956B. PCA9952/PCA9955 have a fault
  test feature that works differently and is not covered by this series.
- Correctly specify MODE2 reset defaults for all supported chips. The
  initialization of MODE2 is introduced in a separate patch now.

v4:
- Make code for output-gain range check and default value clearer
- Use dev_get_drvdata() instead of i2c_get_clientdata()
- Use devres for sysfs group

v3:
- Collect Reviewed-bys
- New patch: Fix fwnode handle leaks in error paths
- New patch: Write global registers before creating LED devices
- Add chip-global sysfs groups before creating LED devices

v2:
- Collect Reviewed-bys
- Use full hardware model names in commit descriptions
- Add nxp, to output-gain property
- Fix nxp,output-gain default in binding docs
- Describe rationale for using register value directly in commit message
- New patch: Fix maximum LED index for 16-channel variants
- Use correct #includes for GPIO consumer and delays
- Use udelay for small delay
- Use sysfs_streq() for has_errors write
- Explicitly initialize MODE2 register, clear reported errors on probe
- Set GRPPWM register on probe

Nora Schiffer (11):
  dt-bindings: leds: pca995x: Describe reset-gpios property
  dt-bindings: leds: pca995x: Describe nxp,output-gain property
  leds: pca995x: Fix maximum LED index for 16-channel variants
  leds: pca995x: Fix fwnode handle leaks in error paths
  leds: pca995x: Write global registers before creating LED devices
  leds: pca995x: Add support for reset GPIO
  leds: pca995x: Make output gain configurable
  leds: pca995x: Initialize MODE2 register on probe
  leds: pca995x: Add sysfs files for error reporting
  leds: pca995x: Do not use full on LED mode
  leds: pca995x: Add support for group brightness control

 .../devicetree/bindings/leds/nxp,pca995x.yaml |  13 +
 drivers/leds/leds-pca995x.c                   | 265 +++++++++++++++---
 2 files changed, 244 insertions(+), 34 deletions(-)

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Geschäftsführer: Detlef Schneider, Rüdiger Stahl, Stefan Schneider
https://www.tq-group.com/