Hi, this patch series adds support for Qualcomm's SPMI Flash LEDs present in the PM8941 PMIC. It is used as part of MSM8974 based devices, like the Nexus 5 (hammerhead), as a camera flash or as a lantern when in torch mode. The driver code is based on the parts of the QPNP LEDs driver from downstream [1] that handled the flash LED. This hardware doesn't have any publicly available documentation, so all my knowledge about its behavior came from reading the downstream driver code and from inspecting the SPMI registers used for the LED operations. I have collected my findings at [2]. Bjorn, Jacek and Pavel, big thanks for your review in v2. I didn't answer the emails but I believe I addressed all of the feedback you gave me. Sorry for the long delay, I'll try to actually answer the feedback this time, and in a timely manner too. The changes in this v3 are too many to list, but the biggest ones were: - The two LEDs can now be operated independently even when in torch mode - The flashes can now strobe consecutive times without needing to manually disable them between strobes - Implemented strobe_get() - Moved dt parsing to a separate function - Split multiplexed torch/flash on/off and torch/flash regulator on/off functions - Removed configurations from the dt-binding that didn't have any visible impact, instead hardcoding them inside the driver - Moved LED dt nodes configuration to hammerhead dts - Set current on brightness callback and timeout on timeout callback, instead of setting everything every time when strobing/turning torch on Fault detection and V4L2 flash wrapper support are still missing but, as others have pointed out before, they can be implemented later if desired. Thanks, Nícolas v2: https://lore.kernel.org/linux-arm-msm/20210126140240.1517044-1-nfraprado@xxxxxxxxxxxxxx/ v1 RFC: https://lore.kernel.org/linux-arm-msm/20201106165737.1029106-1-nfraprado@xxxxxxxxxxxxxx/ [1] https://github.com/AICP/kernel_lge_hammerhead/blob/n7.1/drivers/leds/leds-qpnp.c [2] https://gitlab.collabora.com/nfraprado/linux/-/wikis/PM8941-Flash-LEDs Nícolas F. R. A. Prado (5): dt-bindings: leds: Add binding for qcom-spmi-flash leds: Add driver for QCOM SPMI Flash LEDs ARM: qcom_defconfig: Enable QCOM SPMI Flash LEDs ARM: dts: qcom: pm8941: Add nodes for QCOM SPMI Flash LEDs ARM: dts: qcom: msm8974-hammerhead: Enable and configure flash LED node .../bindings/leds/leds-qcom-spmi-flash.yaml | 93 ++ .../qcom-msm8974-lge-nexus5-hammerhead.dts | 20 + arch/arm/boot/dts/qcom-pm8941.dtsi | 25 + arch/arm/configs/qcom_defconfig | 2 + drivers/leds/flash/Kconfig | 8 + drivers/leds/flash/Makefile | 1 + drivers/leds/flash/leds-qcom-spmi-flash.c | 1251 +++++++++++++++++ 7 files changed, 1400 insertions(+) create mode 100644 Documentation/devicetree/bindings/leds/leds-qcom-spmi-flash.yaml create mode 100644 drivers/leds/flash/leds-qcom-spmi-flash.c -- 2.32.0
