Lots of regulator drivers have checks in their map_voltage() functions
to verify that the result of the mapping is in the range originally
specified. Factor these out in the core and provide a bit of extra
defensiveness for other drivers by doing the check in the core.

Since we're now doing a list_voltage() earlier move the current mapping
back to a voltage out into the set_voltage() call to save redoing it.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Currently regulator_is_supported_voltage() works by enumerating the set
of voltages which can be set by the regulator but the checks we're doing
to impose constraints mean that if we can't vary the voltage we'll not
report any voltages as supported even though the regulator is actually
set at that voltage.

We could fix the voltage listing but this would mean that list_voltage()
could end up going to the hardware to get the current voltage which isn't
expected (it's supposed to be very cheap) so instead special case things
when we can't change the voltage and compare the requested range against
the current voltage.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

commit 222cc7b1 (regulator: core: Allow multiple requests of a single supply mapping)
removed the usage of get_device_regulator().

Remove the function definition too amd get rid of the following warning:

drivers/regulator/core.c:112:26: warning: 'get_device_regulator' defined but not used [-Wunused-function]
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Sometimes it may be useful to allow a device to request a supply multiple
times, for example in order to allow framework management of some uses of
the supply with some additional driver specific management or in order to
allow multiple children of an MFD to work with the supply. Currently this
is not possible due to the creation of

Solve this by removing the requested_uA entry (we have no current users
of this feature anyway) and ignoring errors creating the symlink to the
consumer. We should do something nicer than this as this causes sysfs to
spew enormous warnings but it allows users to run for now.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@ti.com>

There is no need to consider waiting for the voltage to ramp if we
didn't manage to set it and looking at the return value is going to be
cheaper than is_enabled().
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

minor optimization: move delay code to where delay is set and
thus where it is used vs in the main line path.
Signed-off-by: NPhilip Rakity <prakity@marvell.com>
Acked-by: NAxel Lin <axel.lin@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

The voltage being set should be passed to the call in handler
requesting the callback.  Currently this is not done.

The calling handler cannot call regulator_get_voltage() to get the
information since the mutex is held by the regulator and
deadlock occurs.

Without this change the receiver of the call in cannot know what
action to take.  This is used, for example, to set PAD voltages
when doing SD vccq voltage changes.

[Review and spelling fix in the commit log from Pankaj Jangra]
Signed-off-by: NPhilip Rakity <prakity@marvell.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Reported-by: NPankaj Jangra <jangra.pankaj9@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

If no regmap is explicitly specified then use dev_get_regmap() to obtain
one. The driver must explicitly enable any actual usage of the regmap
so there's no concern with unwanted usage.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@ti.com>

devres_release() will call the destructor for the resource as well as
freeing the devres data.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@ti.com>

If the regulator is not on, it won't take time setting new voltage.
So only call set_voltage_time_sel() to get the necessary delay when
the regulator is on.
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Some regulator hardware use table based mapping can set volt_table in
regulator_desc and use regulator_list_voltage_table() for their list_voltage
callback.
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Acked-by: NLiam Girdwood <lrg@ti.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@ti.com>

If we fail while registering a regulator make sure we release the supply
for the regulator if there is one.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@ti.com>
Cc: stable@vger.kernel.org

Integer division may truncate the result.
Use DIV_ROUND_UP to ensure simple linear voltage mappings falls within the
specified range.
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

A lot of regulator hardware maps selectors on to voltages with a simple
linear mapping function

    selector = base + (selector * step size)

Provide off the shelf list_voltage() and map_voltage() operations which
use new min_uV and uV_step members in the regulator_desc to implement
this function.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@ti.com>

In order to allow more drivers to factor things out into data allow
drivers to provide a mapping function to convert voltages into selectors.
This allows any driver to use set_voltage_sel(). The existing mapping
based on iterating over list_voltage() is provided as an operation which
can be assigned to the new map_voltage() function though for ease of
transition it is treated as the default.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@ti.com>

The core really wants a struct device to be supplied for regulators and
there's no reason this should be impossible so provide one so complain
if we didn't get one.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@ti.com>

It turns out that (quite surprisingly) devres_destroy() only undoes the
devres mapping, it doesn't destroy the underlying resource, meaning that
anything using devm_regulator_put() would leak. While we wait for the new
devres_release() which does what we want to get merged open code it in
devm_regulator_put().
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@ti.com>

If a regulator is always on for any reason then cache that when the
consumer is created and use it to optimise away the need to take locks
or recurse up the supply tree when consumers do enable or disable calls.
The scheduling of asynchronous work for bulk enables is also skipped.

We don't actually check if the device physically supports control on the
basis that constraints allowing status changes on physically always on
regulators are nonsensical anyway.

This is a very common pattern in hardware - it's normal to have some
power supplies that have either no software control or are critical to
system function - so many systems should be able to benefit.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@ti.com>

regulator_set_optimum_mode needs set_mode to properly work.
Add checking for set_mode callback in case it may be not implemented.
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Since the enable(), disable() and is_enabled() operations for most regmap
based regulators come down to reading and updating a single register bit
we can factor out the code and allow these drivers to just define which
bit to update using the enable_reg and enable_mask fields in their desc
and then use operations provided by the core.

As well as the code saving this opens the door to future optimisation of
the bulk operations - if the core can realise that we are updating a
single register for multiple regulators then it should be able to combine
these updates into a single physical operation.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@ti.com>

Since the voltage selector operations are intended to directly map a
bitfield in the device register map into regulator API operations the
code for implementing them is usually very standard we can save some
code by providing standard implementations for devices using the regmap
API.

Drivers using regmap can pass their regmap in in the regmap_config
struct, set vsel_reg and vsel_mask in their regulator_desc and then
use regulator_{get,set}_voltage_sel_regmap in their ops. This saves
a small amount of code from each driver.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@ti.com>

Since many regulators use regmap for register I/O and since there's quite
a few very common patterns in the code allow drivers to pass in a regmap
to the core for use in generic code.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@ti.com>

In current implementation, to support set_suspend_voltage and set_suspend_mode
the regulator code needs the regulator driver to implement both
set_suspend_enable and set_suspend_disable callbacks.

This patch removes this limitation. In the case set_suspend_enable and/or
set_suspend_disable are NULL, the regulator code assumes we don't need to
do any thing to enable/disable regulator when system is suspended and
then will continue to handle set_suspend_mode and set_suspend_voltage.

Currently the regulator core creates suspend state related sysfs entries only
if both set_suspend_enable and set_suspend_disable callbacks are not NULL.
A side-effect of this change is that the regulator core will create suspend
state related sysfs entries unconditionally now.
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

When supplied by another regulator, returns the supply regulator's output
voltage for inpu_uV.
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

We don't support missing configs at all so segfaulting isn't that bad
but since we've got checks in the code move the dereference after them.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Rather than adding new arguments to regulator_register() every time we
want to add a new bit of dynamic information at runtime change the function
to take these via a struct. By doing this we avoid needing to do further
changes like the recent addition of device tree support which required each
regulator driver to be updated to take an additional parameter.

The regulator_desc which should (mostly) be static data is still passed
separately as most drivers are able to configure this statically at build
time.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

In currently implementation of _regulator_do_set_voltage, set_voltage_time_sel will
only be called if set_voltage_sel is implemented.

set_voltage_time_sel actually only needs get_voltage_sel to get old_selector.

This patch makes regulator core support set_voltage_time_sel for drivers
implement either set_voltage or set_voltage_sel.
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Drivers should be able to declare their descriptors const and the framework
shouldn't ever be modifying the desciptor. Make the parameter and the
pointer in regulator_dev const to enforce this.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Ensure we always apply the supply mapping when doing a lookup rather than
only doing it in non-DT cases, ensuring that regulators with supplies
specified in the regulator_desc can find their supplies on non-DT systems
and generally making the code more obvious.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

When using device tree if there's no binding for a supply then there's no
way that one could appear later so just fail permanently right away. This
avoids wasting time trying to reprobe when that can never work.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

When cleaning up after a failed bulk_disable() we try to reenable any
supplies that we did manage to disable - complain if we fail to do that
when we try.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

If a regulator with a supply is being unregistered we will call
regulator_put() to release the supply with the regulator_list_mutex held
but this deadlocks as regulator_put() takes the same lock. Fix this by
releasing the supply before we take the mutex in regulator_unregister().
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

of_parse_phandle() returns NULL either if the property name
itself does not exist or if it (exists and) does not
reference a valid phandle.
Giving out a warn like the one below (that the property references
an invalid phandle) can be confusing when the property itself
does not exist in the node.
Fix it with a more sensible message and make it a dev_dbg instead
of a dev_warn.
Reported-by: NTomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: NRajendra Nayak <rnayak@ti.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

If we fail to locate a requested regulator return -EPROBE_DEFER. If drivers
pass this error code through to their caller (which they really should)
then this will ensure that the probe is retried later when further devices
become available.  In the unusual case where a driver doesn't want this
it can override the default behaviour.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NLiam Girdwood <lrg@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

rdev->desc->ops->set_voltage_time_sel may return negative error code.
Set delay to 0 and also show warning if set_voltage_time_sel returns error.
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

If CONFIG_DEBUG_FS=y debugfs functions will never return an
ERR_PTR. Instead they'll return NULL. The intent is to remove
ifdefs in calling code.

Update the code to reflect this. We gain an extra dentry pointer
per struct regulator and struct regulator_dev but that should be
ok because most distros have debugfs compiled in anyway.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>