leds: flash: Add driver to support flash LED module in QCOM PMICs

Add initial driver to support flash LED module found in Qualcomm
Technologies, Inc. PMICs. The flash module can have 3 or 4 channels
and each channel can be controlled indepedently and support full scale
current up to 1.5 A. It also supports connecting two channels together
to supply one LED component with full scale current up to 2 A. In that
case, the current will be split on each channel symmetrically and the
channels will be enabled and disabled at the same time.

Signed-off-by: Fenglin Wu <quic_fenglinw@quicinc.com>
Tested-by: Luca Weiss <luca.weiss@fairphone.com> # sm7225-fairphone-fp4 + pm6150l
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230303095023.538917-2-quic_fenglinw@quicinc.com

Author: Fenglin Wu

drivers/leds/flash/Kconfig

@@ -61,6 +61,21 @@ config LEDS_MT6360
 	  Independent current sources supply for each flash LED support torch
 	  and strobe mode.
 
+config LEDS_QCOM_FLASH
+	tristate "LED support for flash module inside Qualcomm Technologies, Inc. PMIC"
+	depends on MFD_SPMI_PMIC || COMPILE_TEST
+	depends on LEDS_CLASS && OF
+	depends on V4L2_FLASH_LED_CLASS || !V4L2_FLASH_LED_CLASS
+	select REGMAP
+	help
+	  This option enables support for the flash module found in Qualcomm
+	  Technologies, Inc. PMICs. The flash module can have 3 or 4 flash LED
+	  channels and each channel is programmable to support up to 1.5 A full
+	  scale current. It also supports connecting two channels' output together
+	  to supply one LED component to achieve current up to 2 A. In such case,
+	  the total LED current will be split symmetrically on each channel and
+	  they will be enabled/disabled at the same time.
+
 config LEDS_RT4505
 	tristate "LED support for RT4505 flashlight controller"
 	depends on I2C && OF

drivers/leds/flash/Makefile

@@ -6,6 +6,7 @@ obj-$(CONFIG_LEDS_AS3645A)	+= leds-as3645a.o
 obj-$(CONFIG_LEDS_KTD2692)	+= leds-ktd2692.o
 obj-$(CONFIG_LEDS_LM3601X)	+= leds-lm3601x.o
 obj-$(CONFIG_LEDS_MAX77693)	+= leds-max77693.o
+obj-$(CONFIG_LEDS_QCOM_FLASH)	+= leds-qcom-flash.o
 obj-$(CONFIG_LEDS_RT4505)	+= leds-rt4505.o
 obj-$(CONFIG_LEDS_RT8515)	+= leds-rt8515.o
 obj-$(CONFIG_LEDS_SGM3140)	+= leds-sgm3140.o