On Odroid XU3/4 and other Exynos5422 based boards there is a case, that
different devices on the board are supplied by different regulators
with non-fixed voltages. If one of these devices temporarily requires
higher voltage, there might occur a situation that the spread between
two devices' voltages is so high, that there is a risk of changing
'high' and 'low' states on the interconnection between devices powered
by those regulators.

Introduce new function regulator_balance_voltage(), which
keeps max_spread constraint fulfilled between a group of coupled
regulators. It should be called if a regulator changes its
voltage or after disabling or enabling. Disabled regulators should
follow changes of the enabled ones, but their consumers' demands
shouldn't be taken into account while calculating voltage of other
coupled regulators.

Find voltages, which are closest to suiting all the consumers' demands,
while fulfilling max_spread constraint, keeping the following rules:
- if one regulator is about to rise its voltage, rise others
  voltages in order to keep the max_spread
- if a regulator, which has caused rising other regulators, is
  lowered, lower other regulators if possible
- if one regulator is about to lower its voltage, but it hasn't caused
  rising other regulators, don't change its voltage if it breaks the
  max_spread

Change regulators' voltages step by step, keeping max_spread constraint
fulfilled all the time. Function regulator_get_optimal_voltage()
should find the best possible change for the regulator, which doesn't
break max_spread constraint. In function regulator_balance_voltage()
optimize number of steps by finding highest voltage difference on
each iteration.

If a regulator, which is about to change its voltage, is not coupled,
method regulator_get_optimal_voltage() should simply return the lowest
voltage fulfilling consumers' demands.

Coupling should be checked only if the system is in PM_SUSPEND_ON state.
Signed-off-by: NMaciej Purski <m.purski@samsung.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

On Odroid XU3/4 and other Exynos5422 based boards there is a case, that
different devices on the board are supplied by different regulators
with non-fixed voltages. If one of these devices temporarily requires
higher voltage, there might occur a situation that the spread between
two devices' voltages is so high, that there is a risk of changing
'high' and 'low' states on the interconnection between devices powered
by those regulators.

Fill coupling descriptor with data obtained from DTS using previously
defined of_functions. Fail to register a regulator, if some data
inconsistency occurs. If some coupled regulators are not yet registered,
don't fail to register, but try to resolve them in late init call.
Signed-off-by: NMaciej Purski <m.purski@samsung.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

On Odroid XU3/4 and other Exynos5422 based boards there is a case, that
different devices on the board are supplied by different regulators
with non-fixed voltages. If one of these devices temporarily requires
higher voltage, there might occur a situation that the spread between
devices' voltages is so high, that there is a risk of changing
'high' and 'low' states on the interconnection between devices powered
by those regulators.

Add new structure "coupling_desc" to regulator_dev, which contains
pointers to all coupled regulators including the owner of the structure,
number of coupled regulators and counter of currently resolved
regulators.

Add of_functions to parse all data needed in regulator coupling.
Provide method to check DTS data consistency. Check if each coupled
regulator's max_spread is equal and if their lists of regulators match.
Signed-off-by: NMaciej Purski <m.purski@samsung.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Setting voltage, enabling/disabling regulators requires operations on
all regulators related with the regulator being changed. Therefore,
all of them should be locked for the whole operation. With the current
locking implementation, adding additional dependency (regulators
coupling) causes deadlocks in some cases.

Introduce a possibility to attempt to lock a mutex multiple times
by the same task without waiting on a mutex. This should handle all
reasonable coupling-supplying combinations, especially when two coupled
regulators share common supplies. The only situation that should be
forbidden is simultaneous coupling and supplying between a pair of
regulators.

The idea is based on clk core.
Signed-off-by: NMaciej Purski <m.purski@samsung.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

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

This regulator supports passing platform data, but enable/sleep
regulators are looked up from the device tree exclusively, so
we can need not touch other files.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NKrzysztof Kozlowski <krzk@kernel.org>
Tested-by: NKrzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

Instead of passing a global GPIO number, pass a descriptor looked
up from the device tree configuration node.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NKrzysztof Kozlowski <krzk@kernel.org>
Tested-by: NKrzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

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

We have augmented the GPIO core to look up the regulator special
GPIO "wlf,ldoena" in commit 6a537d48
"gpio: of: Support regulator nonstandard GPIO properties".
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NCharles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Add support for configuring the machine constraints
valid_modes_mask element based on a list of allowed modes
specified via a device tree property.
Signed-off-by: NDavid Collins <collinsd@codeaurora.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

Regulators attached via RPMh on Qualcomm sdm845 apparently are
write-only.  Specifically you can send a request for a certain voltage
but you can't read back to see what voltage you've requested.  What
this means is that at bootup we have absolutely no idea what voltage
we could be at.

As discussed in the patches to try to support the RPMh regulators [1],
the fact that regulators are write-only means that its driver's
get_voltage_sel() should return an error code if it's called before
any calls to set_voltage_sel().  This causes problems in
machine_constraints_voltage() when trying to apply the constraints.

A proposed fix was to come up with an error code that could be
returned by get_voltage_sel() which would cause the regulator
framework to simply try setting the voltage with the current
constraints.

In this patch I propose the error code -ENOTRECOVERABLE.  In errno.h
this error is described as "State not recoverable".  Though the error
code was originally intended "for robust mutexes", the description of
the error code seems to apply here because we can't read the state of
the regulator.  Also note that the only existing user of this error
code in the regulator framework is tps65090-regulator.c which returns
this error code from the enable() call (not get_voltage() or
get_voltage_sel()), so there should be no existing regulators that
might accidentally get the new behavior.  (Side note is that tps65090
seems to interpret this error code to mean an error that you can't
recover from rather than some data that can't be recovered).

[1] https://patchwork.kernel.org/patch/10340897/Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

SY8106A is an I2C attached single output regulator made by Silergy Corp,
which is used on several Allwinner H3/H5 SBCs to control the power
supply of the ARM cores.

Add a driver for it.
Signed-off-by: NOndrej Jirman <megous@megous.com>
[Icenowy: Change commit message, remove enable/disable code, add default
 ramp_delay, add comment for go bit, add code for fixed mode voltage]
Signed-off-by: NIcenowy Zheng <icenowy@aosc.io>
Reviewed-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

If device tree is not enabled, of_find_regulator_by_node() should have
a dummy function since the function call is still there.

This is to fix build error after CONFIG_NO_AUTO_INLINE is introduced.
If this option is enabled, GCC will not auto-inline functions that are
not explicitly marked as inline.

In this case (no CONFIG_OF), the copmiler will report error in function
regulator_dev_lookup().

W/O NO_AUTO_INLINE, function of_get_regulator() is auto-inlined and then
the call to of_find_regulator_by_node() is optimized out since
of_get_regulator() always return NULL.

W/ NO_AUTO_INLINE, the return value of of_get_regulator() is a variable
so the call to of_find_regulator_by_node() cannot be optimized out. So
we need a stub of_find_regulator_by_node().

static struct regulator_dev *regulator_dev_lookup(struct device *dev,
						  const char *supply)
{
	struct regulator_dev *r = NULL;
	struct device_node *node;
	struct regulator_map *map;
	const char *devname = NULL;

	regulator_supply_alias(&dev, &supply);

	/* first do a dt based lookup */
	if (dev && dev->of_node) {
		node = of_get_regulator(dev, supply);
		if (node) {
			r = of_find_regulator_by_node(node);
			if (r)
				return r;
	...
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The BD9571MWV PMIC supports backup mode, which keeps one or more DDR
rails powered while the main SoC is powered down.

Which DDR rails are to be kept powered is board-specific, and controlled
using the optional "rohm,ddr-backup-power" DT property.  In the absence
of this property, backup mode is not available.

Backup mode can be enabled or disabled by the user using the standard
"wakeup" virtual file in sysfs, e.g. to enable:

    echo enabled > /sys/devices/platform/soc/e60b0000.i2c/i2c-7/7-0030/bd9571mwv-regulator.2.auto/power/wakeup

When the PMIC is configured for backup mode, the role of the accessory
power switch changes from a power switch to a wake-up switch.
Two types of switches (or signals) can be used:
  A. With a momentary power switch (or pulse signal), the PMIC is
     configured for backup mode in the PMIC driver's suspend callback,
     during system suspend.
     Backup mode is enabled by default, as there is no further impact
     during normal system operation.

  B. With a toggle power switch (or level signal), the following steps
     must be followed exactly:
       1. Configure PMIC for backup mode,
       2. Switch accessory power switch off, to prepare for system
          suspend, which is a manual step not controlled by software,
       3. Suspend system.
     This mode is not yet supported by the driver.

As the switch type is board-specific, and cannot be determined
automatically, it is obtained from the presence of one of the
"rohm,rstbmode-*" properties in DT.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

Like axp221, axp223, axp813 the axp803 is also supporting external
regulator to drive the  OTG VBus through N_VBUSEN PMIC pin.

Add support for it.
Signed-off-by: NJagan Teki <jagan@amarulasolutions.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Reviewed-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

It seems that the loop index i is not being incremented and hence
potentially the while loop could spin forever. Fortunately with the
data being used this does not appear to happen at the moment.
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Acked-by: NCharles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

In of_get_regulation_constraints() we were taking the result of
of_map_mode() (an unsigned int) and assigning it to an int.  We were
then checking whether this value was -EINVAL.  Some implementers of
of_map_mode() were returning -EINVAL (even though the return type of
their function needed to be unsigned int) because they needed to
signal an error back to of_get_regulation_constraints().

In general in the regulator framework the mode is always referred to
as an unsigned int.  While we could fix this to be a signed int (the
highest value we store in there right now is 0x8), it's actually
pretty clean to just define the regulator mode 0x0 (the lack of any
bits set) as an invalid mode.  Let's do that.

Fixes: 5e5e3a42 ("regulator: of: Add support for parsing initial and suspend modes")
Suggested-by: NJavier Martinez Canillas <javierm@redhat.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Reviewed-by: NJavier Martinez Canillas <javierm@redhat.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

This version is exists in the Samsung Galaxy Tab 10.1 which is based on the
Nvidia Tegra 2 board. The TPS658624 has the same SM2 voltage table as
TPS658623.
Signed-off-by: Nryang <decatf@gmail.com>
Acked-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

pfuze3000 datasheet(Rev.9.0) from:

https://www.nxp.com/docs/en/data-sheet/PF3000.pdf

updates sw1a's voltage range, the settings for 1.450V and 1.475V
are replaced with 1.8V and 3.3V:

5b'11110 1.450 (SW1B), 1.8 (SW1A/SW1AB)
5b'11111 1.475 (SW1B), 3.3 (SW1A/SW1AB)

the voltage calculation using steps is NOT available for sw1a now,
use voltage table instead.
Signed-off-by: NAnson Huang <Anson.Huang@nxp.com>
Signed-off-by: NRobin Gong <yibin.gong@nxp.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Buck10 is a multi(dual) phase regulator. So as part of enabling it
turn on the LP87565_BUCK_CTRL_1_FPWM_MP_0_2 bit which forces it to
operate always in multiphase and forced-PWM operation mode.
This helps improve the transient voltage response while switching OPP.
Signed-off-by: NKeerthy <j-keerthy@ti.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The slew rate might need a +/- 15% margin as per the latest data manual:

	http://www.ti.com/lit/ds/snvsb22/snvsb22.pdf

Hence take a conservative approach to program 85% of the original
hardware slew rate so that the software accommodates the margin
delay while voltage switching. Hence reduce the default ramp_delay
populated in the descriptors also by 15%.
Signed-off-by: NKeerthy <j-keerthy@ti.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The AB8540 was an evolved version of the AB8500, but it was never
mass produced or put into products, only reference designs exist.
The upstream support was never completed and it is unlikely that
this will happen so drop the support for now to simplify
maintenance of the AB8500.

Cc: Loic Pallardy <loic.pallardy@st.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

Add the pm8998 and pmi8998 regulators as used in the MSM8998 platform.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

Signed-off-by: NMark Brown <broonie@kernel.org>

These seem to be leftovers from previous developments of the driver but
they never got removed. Dropping them still allows the code to compile
so everything must be fine.
Signed-off-by: NStephen Boyd <swboyd@chromium.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

When the label is empty, it causes missing information and limits diagnostics
for instances such as 'cat /sys/kernel/debug/gpio'

Setting the label to the regulator supply_name will point to the device
using the gpio(s).
Signed-off-by: NNicholas Lowell <nlowell@lexmark.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Re-order error handling code and gotos to avoid leaks in error handling
paths.

Fixes: 9f946099 ("regulator: gpio: fix parsing of gpio list")
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: NMark Brown <broonie@kernel.org>

This chip is found on Google Chromecast and Valve Steam Link devices.
It provides two DC regulators with I2C voltage control, separate GPIO
enable pins and one sleep mode pin.

This driver does not expose GPIO functionality, but supports voltage
control in 1.0-2.2V range, based on I2C register information given in
Chromecast kernel driver by Jisheng Zhang.

Cc: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Signed-off-by: NAlexander Monakov <amonakov@ispras.ru>
Signed-off-by: NMark Brown <broonie@kernel.org>

When resuming from idle with the new suspend mode configuration support
we go through the resume callbacks with a state of PM_SUSPEND_TO_IDLE
which we don't have regulator constraints for, causing an error:

    dpm_run_callback(): regulator_resume_early+0x0/0x64 returns -22
    PM: Device regulator.0 failed to resume early: error -22

Avoid this and similar errors by treating missing constraints as a noop.

See also commit 57a0dd18 ("regulator: Fix suspend to idle"),
which fixed the suspend part.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@kernel.org>

This augments the DA9211 regulator driver to fetch its GPIO descriptors
directly from the device tree using the newly exported
devm_get_gpiod_from_child().
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

When setting up a fixed regulator on the DA9055, pass a descriptor
instead of a global GPIO number. This facility is not used in the
kernel so we can easily just say that this should be a descriptor
if/when put to use.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

We are currently passing a GPIO number from the global GPIO numberspace
into the regulator core for handling enable GPIOs. This is not good
since it ties into the global GPIO numberspace and uses gpio_to_desc()
to overcome this.

Start supporting passing an already initialized GPIO descriptor to the
core instead: leaf drivers pick their descriptors, associated directly
with the device node (or from ACPI or from a board descriptor table)
and use that directly without any roundtrip over the global GPIO
numberspace.

This looks messy since it adds a bunch of extra code in the core, but
at the end of the patch series we will delete the handling of the GPIO
number and only deal with descriptors so things end up neat.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

If an unlikely failure in 'of_get_regulator_init_data()' occurs, we must
release the reference on the current 'child' node before returning.
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: NMark Brown <broonie@kernel.org>

stm32_vrefbuf_enable() wrongly checks VRR bit: 0 stands for not ready,
1 for ready. It currently checks the opposite.
This makes enable routine to exit immediately without waiting for ready
flag.

Fixes: 0cdbf481 ("regulator: Add support for stm32-vrefbuf")
Signed-off-by: NFabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

When suspending to idle with the new suspend mode configuration support
we go through the suspend callbacks with a state of PM_SUSPEND_TO_IDLE
which we don't have regulator constraints for, causing an error.  Avoid
this and similar errors by treating missing constraints as a noop.
Reported-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Tested-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@kernel.org>

3d67fe95 (regulator: core: Refactor regulator_list_voltage()) missed
one user of regulator_list_voltage(), update for that.
Signed-off-by: NMark Brown <broonie@kernel.org>

Change _regulator_list_voltage() argument from regulator to
regulator_dev in order to provide better separation of core layers.
Allow calling _regulator_list_voltage() from functions, with
regulator_dev argument. This refactoring is needed in order to
implement setting voltage of coupled regulators.
Signed-off-by: NMaciej Purski <m.purski@samsung.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

As of_find_regulator_by_node() is an of function it should be moved from
core.c to of_regulator.c. It provides better separation of device tree
functions from the core and allows other of_functions in of_regulator.c
to resolve device_node to regulator_dev. This will be useful for
implementation of parsing coupled regulators properties.

Declare of_find_regulator_by_node() function in internal.h as well as
regulator_class and dev_to_rdev(), as they are needed by
of_find_regulator_by_node().
Signed-off-by: NMaciej Purski <m.purski@samsung.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

In this patch, consumers are allowed to set suspend voltage, and this
actually just set the "uV" in constraint::regulator_state, when the
regulator_suspend_late() was called by PM core through callback when
the system is entering into suspend, the regulator device would act
suspend activity then.

And it assumes that if any consumer set suspend voltage, the regulator
device should be enabled in the suspend state.  And if the suspend
voltage of a regulator device for all consumers was set zero, the
regulator device would be off in the suspend state.

This patch also provides a new function hook to regulator devices for
resuming from suspend states.
Signed-off-by: NChunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

Regualtor suspend/resume functions should only be called by PM suspend
core via registering dev_pm_ops, and regulator devices should implement
the callback functions.  Thus, any regulator consumer shouldn't call
the regulator suspend/resume functions directly.

In order to avoid compile errors, two empty functions with the same name
still be left for the time being.
Signed-off-by: NChunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

The items "disabled" and "enabled" are a little redundant, since only one
of them would be set to record if the regulator device should keep on
or be switched to off in suspend states.

So in this patch, the "disabled" was removed, only leave the "enabled":
  - enabled == 1 for regulator-on-in-suspend
  - enabled == 0 for regulator-off-in-suspend
  - enabled == -1 means do nothing when entering suspend mode.
Signed-off-by: NChunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

Some regulator consumers would like to make the regulator device
keeping a voltage range output when the system entering into
suspend states.

Making regulator voltage be an array can allow consumers to set voltage
for normal state as well as for suspend states through the same code.
Signed-off-by: NChunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>