regulator: lp8788-buck: Fully convert to GPIO descriptors

This converts the LP8788 BUCK regulator driver to use GPIO
descriptors.

BUCK1 can use one DVS GPIO and BUCK2 can use two DVS GPIOS,
and no more so just hardcode two GPIO descriptors into
the per-DVS state containers.

Obtain the descriptors from each regulators subdevice.

As there are no in-tree users, board files need to populate
descriptor tables for the buck regulator devices when
they want to use this driver. BUCK1 need a GPIO descriptor
at index 0 and BUCK2 needs two GPIO descriptors at
indices 0 and 1.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://msgid.link/r/20240220-descriptors-regulators-v1-3-097f608694be@linaro.org
Acked-by: Lee Jones <lee@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

regulator: lp8788-ldo: Pass descriptor instead of GPIO number

Instead of passing a global GPIO number, pass a descriptor looked
up with the standard devm_gpiod_get_index_optional() call.

This driver has supported passing a LDO enable GPIO for years,
yet this facility has never been put to use in the upstream kernel.
If someone desires to put in place GPIO control for the LDOs,
this can be done by adding a GPIO descriptor table in the MFD
nexus in drivers/mfd/lp8788.c for the LDO device when spawning the
MFD children, or using a board file.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

backlight: add new lp8788 backlight driver

TI LP8788 PMU supports regulators, battery charger, RTC, ADC, backlight
dri= ver and current sinks. This patch enables LP8788 backlight module.

(Brightness mode)
The brightness is controlled by PWM input or I2C register.
All modes are supported in the driver.

(Platform data)
Configurable data can be defined in the platform side.
name : backlight driver name. (default: "lcd-backlight")
initial_brightness : initial value of backlight brightness
bl_mode : brightness control by PWM or lp8788 register
dim_mode : dimming mode selection
full_scale : full scale current setting
rise_time : brightness ramp up step time
fall_time : brightness ramp down step time
pwm_pol : PWM polarity setting when bl_mode is PWM based
period_ns : platform specific PWM period value. unit is nano.

The default values are set in case no platform data is defined.

[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: Thierry Reding <thierry.reding@avionic-design.de>
Cc: "devendra.aaru" <devendra.aaru@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lp8788-charger: Fix ADC channel names

The name of ADC channel is configurable in the platform side. This name is
referenced in the IIO consumer driver. To get the IIO channel, specific
name in the platform data is used as an parameter of the
iio_channel_get(). Thus, lp8788_adc_id platform data are replaced with
specific names.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>

mfd: Add lp8788 mfd driver

TI LP8788 PMU provides regulators, battery charger, ADC,
RTC, backlight driver and current sinks.

This MFD patch supports the I2C communication using the regmap,
the interrupt handling using the linear IRQ domain and
configurable platform data structures for each driver module.

(Driver Architecture)

< mfd devices >
LP8788 HW .......... mfd .......... regulator drivers
I2C power supply driver
IRQs iio adc driver
rtc driver
backlight driver
current sink drivers

o regulators : LDOs and BUCKs
o power supply : Battery charger
o iio adc : Battery voltage/temperature
o rtc : RTC and alarm
o backlight
o current sink : LED and vibrator

All MFD device modules are registered by LP8788 MFD core driver.
For sharing information such like the virtual IRQ number,
MFD core driver uses the resource structure.
Then each module can retrieve the specific IRQ number and detect it
in the IRQ thread.

Configurable platform data is handled in each driver module.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>