[PATCH v3 0/4] leds: flash: LM3643 dual LED flash driver

[Rillian Grant <rillian.grant@gmail.com>]

This series adds a flash LED driver for the Texas Instruments
LM3643. I wrote it to support the Windows Hello NIR illuminator on my
ThinkPad X9-15 Gen 1, which has a single LED connected to both current
sources. The driver has also been tested by Ruslan Koreev on a ThinkPad
X1 Carbon Gen 14.

On both ThinkPad models the chip is described by ACPI but has no _DSD.
The original RFC asked how to supply the missing child nodes. This
series includes DMI-matched software nodes for both laptop models.

1/4 DT binding
2/4 driver
3/4 DMI match table and values for the X1 Carbon
4/4 DMI entry for the X9-15 Gen 1

Changes in v3:
- dt-bindings: document the enable-gpios (HWEN), flash-gpios (STROBE)
  and vin-supply (IN) connections (Krzysztof Kozlowski)
- dt-bindings: drop redundant minimum: 0, use led-controller as the node
  name in the example and tidy formatting (Krzysztof Kozlowski)
- driver: enable the optional vin-supply and drive the optional HWEN
  GPIO high at probe
- driver: reject an out-of-range max-brightness rather than clamping after
  registration (previously LED core applied max-brightness exposing sysfs
  before the clamp)
- driver: allow a torch output to be switched off while the device is
  flashing (previously returned -EBUSY)
- driver: take the chip lock when claiming current outputs
- driver: fix indentation in lm3643_torch_get_brightness()
- 3/4, 4/4: use DMI_EXACT_MATCH for the DMI entries
- 3/4: log use of the DMI description with dev_dbg() instead of
  dev_info()

Changes in v2:
- Rebased onto leds/for-leds-next
- dt-bindings: make flash-max-microamp, led-max-microamp and
  flash-max-timeout-us required
- driver: return device to standby state when the last output is
  switched off (squashed fix provided by Ruslan Koreev)
- New 3/4: DMI mechanism and entry for the X1 Carbon developed by
  Ruslan. Plus a minor update to provide a reg property for consistency
  with the DT bindings.
- New 4/4: DMI entry for the X9-15 Gen 1 and update struct names to be
  model-specific.

v2: https://lore.kernel.org/all/20260928094302.86966-1-rillian.grant@gmail.com/
v1: https://lore.kernel.org/all/20260821083620.68324-1-rillian.grant@gmail.com/

Rillian Grant (3):
  dt-bindings: leds: Document TI LM3643 dual LED flash driver
  leds: flash: Add support for the TI LM3643 dual LED flash driver
  leds: flash: lm3643: Describe the LED on the Lenovo ThinkPad X9-15 Gen
    1

Ruslan Koreev (1):
  leds: flash: lm3643: Describe the LED of ACPI boards without LED nodes

 .../devicetree/bindings/leds/ti,lm3643.yaml   | 143 +++
 MAINTAINERS                                   |   7 +
 drivers/leds/flash/Kconfig                    |  12 +
 drivers/leds/flash/Makefile                   |   1 +
 drivers/leds/flash/leds-lm3643.c              | 929 ++++++++++++++++++
 5 files changed, 1092 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/ti,lm3643.yaml
 create mode 100644 drivers/leds/flash/leds-lm3643.c


base-commit: 05b4738b0078f7d6f154f68068a11c8a0635e9df
-- 
2.56.0