The "regulator-initial-mode" and "regulator-mode" DT properties allows
to configure the regulator operating modes at startup or when a system
enters into a susend state.

But these properties use as valid values the operating modes supported
by each device while the core deals with the standard operating modes.
So a mapping function is needed to translate from the hardware specific
modes to the standard ones.

This mapping is a non-varying configuration for each regulator, so add
a function pointer to struct regulator_desc that will allow drivers to
define their callback to do the modes translation.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>

Most drivers do not set the ena_gpio field of struct regulator_config
before passing it to the regulator core. This is fine as long as the
gpio identifier that is passed is a positive integer. But the gpio
identifier 0 is also valid. So we are not able to decide wether we got a
real gpio identifier or not based on a 0 in ena_gpio.

To be able to decide if it is a valid gpio that got passed, this patch
adds a ena_gpio_initialized field that should be set if was initialized
with a correct value, either a gpio >= 0 or a negative error number. The
core then checks if ena_gpio or ena_gpio_initialized before handling it
as a gpio. This way we maintain backwards compatibility and fix the
behaviour for gpio number 0.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

Currently regulator drivers which support DT all repeat very similar code
to supply a list of known regulator identifiers to be matched with DT,
convert that to platform data which is then matched up with the regulators
as they are registered. This is both fiddly to get right and for devices
which can use the standard helpers to provide their operations is the main
source of code in the driver.

Since this code is essentially identical for most drivers we can factor it
out into the core, moving the identifiers in the match table into the
regulator descriptors and also allowing drivers to pass in the name of the
subnode to search. When a driver provides an of_match string for the
regulator the core will attempt to use that to obtain init_data, allowing
the driver to remove all explicit code for DT parsing and simply provide
data instead.

The current code leaks the phandles for the child nodes, this will be
addressed incrementally and makes no practical difference for FDT anyway
as the DT data structures are never freed.

Signed-off-by: Mark Brown <broonie@linaro.org>

Fix kernel-doc warnings in regulator header files:

Warning(..//include/linux/regulator/machine.h:140): No description found for parameter 'ramp_disable'
Warning(..//include/linux/regulator/driver.h:279): No description found for parameter 'linear_ranges'
Warning(..//include/linux/regulator/driver.h:279): No description found for parameter 'n_linear_ranges'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

Fix below build warning:
CC [M]  drivers/regulator/hi6421-regulator.o
drivers/regulator/hi6421-regulator.c:356:2: warning: initialization discards 'const' qualifier from pointer target type [enabled by default]

This is a revert of commit 716845ebeb50 ("regulator: core: Fix build error due
to const qualifier for ops"). The build error was fixed by commit 39f5460d7f9c
("regulator: core: add const to regulator_ops and fix build error in mc13892").

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

Drop const qualifier for ops of struct regulator_desc.
Allow regulator drivers to update ops before registering regulator.

Fix below build error:
  CC [M]  drivers/regulator/mc13892-regulator.o
drivers/regulator/mc13892-regulator.c: In function 'mc13892_regulator_probe':
drivers/regulator/mc13892-regulator.c:586:3: error: assignment of member 'set_mode' in read-only object
drivers/regulator/mc13892-regulator.c:588:3: error: assignment of member 'get_mode' in read-only object
make[2]: *** [drivers/regulator/mc13892-regulator.o] Error 1
make[1]: *** [drivers/regulator] Error 2
make: *** [drivers] Error 2

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

Some regulator require a minimum delay between its disable and next enable.
This is to avoid damages when out-of-range frequent disable/enable of a
single regulator can bring to the regulator chip.

Add @off_on_delay to struct regulator_desc. Device drivers' can use this field
to set this guard time.

Add @last_off_jiffy to struct regulator_dev. When @off_on_delay is set by
driver, regulator core can store its last off (disable) time into this field.

Signed-off-by: Guodong Xu <guodong.xu@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>