mbox series

[v9,0/5] Add a multicolor LED driver for groups of monochromatic LEDs

Message ID 20230616095746.872220-1-jjhiblot@traphandler.com
Headers show
Series Add a multicolor LED driver for groups of monochromatic LEDs | expand

Message

Jean-Jacques Hiblot June 16, 2023, 9:57 a.m. UTC 
Some HW design implement multicolor LEDs with several monochromatic LEDs.
Grouping the monochromatic LEDs allows to configure them in sync and use
the triggers.
The PWM multicolor LED driver implements such grouping but only for
PWM-based LEDs. As this feature is also desirable for the other types of
LEDs, this series implements it for any kind of LED device.

changes v8->v9:
  - rebased on top of lee-leds/for-leds-next
  - updated kernel version and date for /sys/class/leds/<led>/color in
    Documentation/ABI/testing/sysfs-class-led
  - dropped patch "leds: class: simplify the implementation of
    devm_of_led_get()" because __devm_led_get() is now used by
    devm_led_get()

changes v7->v8:
 - consistently use "LEDs group multicolor" throughout the code.
 - rename some variables with more explicit names.
 - improve comments.
 - use the 100-characters per line limit.

changes v6->v7:
 - in led_mcg_probe() increment the counter at the end of the loop for
   clarity.

changes v5->v6:
 - restore sysfs access to the leds when the device is removed

changes v4->v5:
 - Use "depends on COMPILE_TEST || OF" in Kconfig to indicate that OF
   is a functional requirement, not just a requirement for the
   compilation.
 - in led_mcg_probe() check if devm_of_led_get_optional() returns an
   error before testing for the end of the list.
 - use sysfs_emit() instead of sprintf() in color_show().
 - some grammar fixes in the comments and the commit logs.

changes v2->v3, only minor changes:
 - rephrased the Kconfig descritpion
 - make the sysfs interface of underlying LEDs read-only only if the probe
   is successful.
 - sanitize the header files
 - removed the useless call to dev_set_drvdata()
 - use dev_fwnode() to get the fwnode to the device.

changes v1->v2:
 - Followed Rob Herrings's suggestion to make the dt binding much simpler.
 - Added a patch to store the color property of a LED in its class
   structure (struct led_classdev).
Jean-Jacques Hiblot (5):
  devres: provide devm_krealloc_array()
  leds: provide devm_of_led_get_optional()
  leds: class: store the color index in struct led_classdev
  dt-bindings: leds: Add binding for a multicolor group of LEDs
  leds: Add a multicolor LED driver to group monochromatic LEDs

 Documentation/ABI/testing/sysfs-class-led     |   9 +
 .../bindings/leds/leds-group-multicolor.yaml  |  64 +++++++
 drivers/leds/led-class.c                      |  45 +++++
 drivers/leds/rgb/Kconfig                      |  13 ++
 drivers/leds/rgb/Makefile                     |   1 +
 drivers/leds/rgb/leds-group-multicolor.c      | 164 ++++++++++++++++++
 include/linux/device.h                        |  13 ++
 include/linux/leds.h                          |   3 +
 8 files changed, 312 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/leds-group-multicolor.yaml
 create mode 100644 drivers/leds/rgb/leds-group-multicolor.c