Commit Graph

228 Commits

Author SHA1 Message Date
Mark Brown aa59802ded regulator: Fix return code from regulator_disable_deferred()
schedule_delayed_work() returns a bool indicating if the work was already
queued when it succeeds so we need to squash a true down to zero.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-10-04 16:50:16 +01:00
Mark Brown da07ecd93b regulator: Implement deferred disable support
It is a reasonably common pattern for hardware to require some delay after
being quiesced before the disable has finalised, especially in mixed signal
devices. For example, an active discharge may be required to ensure that
the circuit starts up again in a known state. Avoid having to implement
such delays in the regulator API by providing regulator_deferred_disable()
which will do a regulator_disable() a specified number of milliseconds
after it is called.

Due to the reference counting done on regulators a deferred disable can
be cancelled by doing another regulator_enable().

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@ti.com>
2011-09-14 10:58:23 +01:00
Mark Brown ba55a9741d regulator: Add debugfs file showing the supply map table
Useful for working out why things aren't getting plugged together properly.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-08-28 17:41:59 +01:00
Mark Brown 54abd335fd regulator: Fix argument format type errors in error prints
We need to dereference the pointers to print their values.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-07-22 11:46:57 +01:00
Axel Lin 1a6958e79f regulator: Fix memory leak in set_machine_constraints() error paths
Properly kfree rdev->constraints in all set_machine_constraints() error paths.
Also properly kfree rdev->constraints in regulator_register() error paths.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-07-22 11:43:59 +01:00
Mark Brown 89f425ed5b regulator: Make core more chatty about some errors
Prevent some head scratching by making the core log about some rare but
possible errors with invalid voltage ranges and modes being set.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-07-22 11:43:00 +01:00
Mark Brown 5de705194e regulator: Add basic per consumer debugfs
Report the requested load and voltage for each consumer in debugfs when it
is enabled.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-07-04 17:09:28 +01:00
Mark Brown 7d51a0dbe5 regulator: Add rdev_crit() macro
No actual users but provide the macro so there's less surprise when it's
not there.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-06-09 19:14:35 +01:00
Mark Brown 3801b86aa4 regulator: Refactor supply implementation to work as regular consumers
Currently the regulator supply implementation is somewhat complex and
fragile as it doesn't look like standard consumers but is instead a
parallel implementation. This causes issues with locking and reference
counting.

Move the implementation over to using standard consumers to address this.
Rather than only notifying the supply on the first enable/disable we do so
every time the regulator is enabled or disabled, simplifying locking as we
don't need to hold a lock on the consumer we are about to enable.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-06-09 19:14:34 +01:00
Mark Brown e0eaedefda regulator: Include the device name in the microamps_requested_ file
We may have multiple devices requesting a supply with the same name so
include the device name in the generated filename for microamps_requested
to avoid duplicate files.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-06-09 19:14:29 +01:00
Mark Brown f5726ae33c regulator: Increase the limit on sysfs file names
With verbose filenames we can easily hit 32 characters.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-06-09 19:14:29 +01:00
Mark Brown f21e0e81d8 regulator: Do bulk enables of regulators in parallel
In order to reduce the impact of ramp times rather than enabling the
regulators for a device in series use async tasks to run the actual
enables. This means that the delays which the enables implement can all
run in parallel, though it does mean that the order in which the
supplies come on may be unstable.

For super bonus fun points if any of the regulators are shared between
multiple supplies on the same device (as is rather likely) then this
will test our locking.  Note that in this case we only delay once for
each physical regulator so the threads shouldn't block each other while
delaying.

It'd be even nicer if we could coalesce writes to a shared enable registers
in PMICs but that's definitely future work, and it may also be useful
and is certainly more achievable to optimise out the parallelism if none
of the regulators implement ramp delays.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-05-30 11:56:57 +01:00
Axel Lin cb220d16f9 regulator: Fix _regulator_get_voltage if get_voltage callback is NULL
In the case of get_voltage callback is NULL, current implementation in
_regulator_get_voltage will return -EINVAL.

Also returns proper error if ret is negative value.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-05-27 10:49:30 +01:00
Mark Brown 4aa922c024 regulator: Only apply voltage constraints from consumers that set them
When applying the set_voltage() requests from consumers skip over those
consumers that haven't set anything, otherwise we'll come out with a
maximum voltage of zero.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-05-27 10:49:09 +01:00
Mark Brown a4b4148379 regulator: If we can't configure optimum mode we're always in the best one
If either a regulator driver can't tell us what the optimum mode is (or
doesn't have modes in the first place) or the system doesn't allow DRMS
changes then it's more helpful for users to just say that we're in the
optimal mode, even if it's from a selection of one.

Still report errors if the process of picking and setting a mode changes as
this may indicate that we're stuck in a low power mode and unable to deliver
a higher current that the consumer just asked for.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-05-27 10:49:09 +01:00
Mark Brown bf5892a816 regulator: Support voltage offsets to compensate for drops in system
Some systems, particularly physically large systems used for early
prototyping, may experience substantial voltage drops between the regulator
and the consumers as a result of long traces in the system. With these
systems voltages may need to be set higher than requested in order to
ensure reliable system operation.

Allow systems to work around such hardware issues by allowing constraints
to supply an offset to be applied to any requested and reported voltages.
This is not ideal, especially since the voltage drop may be load dependant,
but is sufficient for most affected systems, it is not expected to be used
in production hardware. The offset is applied after all constraint
processing so constraints should be specified in terms of consumer values
not physically configured values.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-05-27 10:34:37 +01:00
Mark Brown 492c826b9f regulator: Remove supply_regulator_dev from machine configuration
supply_regulator_dev (using a struct pointer) has been deprecated in favour
of supply_regulator (using a regulator name) for quite a few releases
now with a warning generated if it is used and there are no current in tree
users so just remove the code.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-05-27 10:34:37 +01:00
Mark Brown 82d158397b regulator: Factor out references to rdev in regulator_force_disable()
Don't go looking up the rdev pointer every time, just use a local variable
like everything else.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-05-27 10:34:37 +01:00
Axel Lin 22c51b47aa regulator: Fix the argument of calling regulator_mode_constrain
The second parameter of regulator_mode_constrain takes a pointer.

This patch fixes below warning:
drivers/regulator/core.c: In function 'regulator_set_mode':
drivers/regulator/core.c:2014: warning: passing argument 2 of 'regulator_mode_constrain' makes pointer from integer without a cast
drivers/regulator/core.c:200: note: expected 'int *' but argument is of type 'unsigned int'

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@vega.(none)>
2011-05-27 10:34:36 +01:00
Mark Brown 2c6082341d regulator: When constraining modes fall back to higher power modes
If a mode requested by a consumer is not allowed by constraints
automatically fall back to a higher power mode if possible. This
ensures that consumers get at least the output they requested while
allowing machine drivers to transparently limit lower power modes
if required.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-05-27 10:34:35 +01:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Linus Walleij 88cd222b25 regulator: provide consumer interface for fall/rise time
This exposes the functionality for rise/fall fime when setting
voltage to the consumers.

Cc: Bengt Jonsson <bengt.g.jonsson@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-03-26 14:15:06 +00:00
Linus Walleij 77af1b2641 regulator: add set_voltage_time_sel infrastructure
This makes it possible to set the stabilization time for voltage
regulators in the same manner as enable_time(). The interface
only supports regulators that implements fixed selectors.

Cc: Bengt Jonsson <bengt.g.jonsson@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-03-26 14:15:06 +00:00
MyungJoo Ham 7a32b589a9 Regulator: add suspend-finish API for regulator core.
The regulator core had suspend-prepare that turns off the regulators
when entering a system-wide suspend. However, it did not have
suspend-finish that pairs with suspend-prepare and the regulator core
has assumed that the regulator devices and their drivers support
autonomous recover at resume.

This patch adds regulator_suspend_finish that pairs with the
previously-existed regulator_suspend_prepare. The function
regulator_suspend_finish turns on the regulators that have always_on set
or positive use_count so that we can reset the regulator states
appropriately at resume.

In regulator_suspend_finish, if has_full_constraints, it disables
unnecessary regulators.

Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
--
Updates
v3
	comments corrected (Thanks to Igor)
v2
	disable unnecessary regulators (Thanks to Mark)
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-03-26 14:15:04 +00:00
Mark Brown 23c2f041ef regulator: If we fail when setting up a supply say which supply
Makes it a bit easier to identify if it's a problem with the supplies,
the usual error would be omitting the supply name entirely.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-03-26 14:15:03 +00:00
Mark Brown 1130e5b3ff regulator: Add initial per-regulator debugfs support
We only expose the use and open counts to userspace, providing a tiny
bit of insight into what the API is up to.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:05 +00:00
Mark Brown 21cf891a47 regulator: Make regulator_has_full_constraints a bool
It's a boolean value so use the type.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:05 +00:00
Mark Brown 13ce29f80f regulator: Clean up logging a bit
The recent introduction of standard regulator API logging macros means
that all our log messages have at least the function name in them and
logging that the constraints are for the regulator API is probably a
bit much.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:05 +00:00
Mark Brown 95a3c23ae6 regulator: Optimise out noop voltage changes
If a consumer sets the same voltage range as is currently configured
for that consumer there's no need to run through setting the voltage
again. This pattern may occur with some CPUfreq implementations where
the same voltage range is used for multiple frequencies.

Reported-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:05 +00:00
Mark Brown 606a256281 regulator: Add API to re-apply voltage to hardware
When cooperating with an external control source the regulator setup
may be changed underneath the API. Currently consumers can just redo
the regulator_set_voltage() to restore a previously set configuration
but provide an explicit API for doing this as optimsations in the
regulator_set_voltage() implementation will shortly prevent that.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:05 +00:00
Mark Brown ded06a5270 regulator: Only notify voltage changes when they succeed
Currently we notify a voltage change whenever we exit set_voltage(),
even if the change failed for some reason (eg, a constraints issue).
This shouldn't cause any substantial ill effects but is wasteful as
listeners get notified on noops. Fix this by moving the notification
into _do_set_voltage() and only notifying if we don't return an error.

Reported-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:05 +00:00
Mark Brown e8eef82b2c regulator: Provide a selector based set_voltage_sel() operation
Many regulator drivers implement voltage setting by looping through a
table of possible values, normally because the set of available voltages
can't be mapped onto selectors with simple calcuation. Factor out these
loops by providing a variant of set_voltage() which takes a selector rather
than a voltage range as an argument and implementing a loop through the
available selectors in the core.

This is not going to be suitable for use with all devices as when the
regulator voltage can be mapped onto selector values with a simple
calculation the linear scan through the available values will be more
expensive than just doing the calculation, especially for regulators
that provide fine grained voltage control.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:04 +00:00
Mark Brown 7579025130 regulator: Factor out voltage set operation into a separate function
Push all the callers of the chip set_voltage() operation out into a single
function to facilitiate future refactoring.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:04 +00:00
Mark Brown 476c2d83c7 regulator: Allow drivers to report voltages as selectors
Since drivers already have to provide an API for translating selectors
into voltages they may as well just report the selector values directly
to the core API rather than implement the lookup themselves. The old
interface is left in place for now, but may be removed in future.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:01 +00:00
Mark Brown 1bf5a1f86a regulator: Use _regulator_get_voltage() consistently
Rather than referencing the get_voltage() operation directly in the
ops struct use the internal _regulator_get_voltage() API call to do
so, facilitating refactoring.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:01 +00:00
Joe Perches 43e7ee33f2 drivers/regulator: Update WARN uses
Align arguments.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:01 +00:00
Thomas Petazzoni 05fda3b1ab regulator: Take into account the requirements of all consumers
Extend the regulator_set_voltage() function to take into account the
voltage requirements of all consumers of the regulator being changed,
in order to set the voltage to the minimum voltage acceptable to all
consumers. The existing behaviour was that the latest
regulator_set_voltage() call would win over previous
regulator_set_voltage() calls even if setting the voltage to a
non-acceptable level from other consumers.

Signed-off-by: Thomas Petazzoni <t-petazzoni@ti.com>
Cc: Liam Girdwood <lrg@slimlogic.co.uk>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:01 +00:00
Joe Perches 5da84fd99b regulator: Add and use rdev_<level> macros
On Tue, 2010-11-30 at 10:52 +0000, Mark Brown wrote:
> On Mon, Nov 29, 2010 at 05:12:56PM -0800, Joe Perches wrote:
> > Just to please broonie...
> > Signed-off-by: Joe Perches <joe@perches.com>
> As usual when fixing review issues please revise your original patch
> rather than posting a fresh patch.

Here's an earlier comment:

On Thu, 2010-11-18 at 13:30 +0000, Mark Brown wrote:
> This looks reasonable, please rebase on top of Daniel's patches and
> submit it properly (with changelog and so on).

Sometimes it's simpler for an upstream maintainer to do
something like:

git am -s <patch1.mbox>
patch -p1 < patch2.mbox
git commit --amend file

instead of back and forthing.

Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:01 +00:00
Mark Brown f8c12fe329 regulator: Copy constraints from regulators when initialising them
Currently the regulator API uses the constraints structure passed in to
the core throughout the lifetime of the object. This means that it is not
possible to mark the constraints as __initdata so if the kernel supports
many boards the constraints for all of them are kept around throughout the
lifetime of the system, consuming memory needlessly. By copying constraints
that are actually used we allow the use of __initdata, saving memory when
multiple boards are supported.

This also means the constraints can be const.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:01 +00:00
Mark Brown 50ba5ca4be regulator: Remove regulator core version announcement
The version hasn't been updated since the regulator API was merged in
2.6.27 so just remove it - now we're in mainline the kernel version is
much more useful.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:00 +00:00
Mark Brown 4c35508fc0 regulator: Fix obfuscated log messages
Don't use %s to format fixed static strings into log messages, it just
makes searching for and reading the message in the kernel source
needlessly hard.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:00 +00:00
Daniel Walker 1d7372e15e drivers: regulator: core: convert to using pr_ macros
The regulator framework uses a lot of printks with a
specific formatting using __func__. This converts them
to use pr_ calls with a central format string.

Cc: bleong@codeaurora.org
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:00 +00:00
Daniel Walker c5e28ed782 drivers: regulator: core: use pr_fmt
This adds a pr_fmt line which uses the __func__ macro. I also
convert the current pr_ lines to remove their __func__ usage.

Cc: bleong@codeaurora.org
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:00 +00:00
Bengt Jonsson acaf6ffefd regulator: enable supply regulator only when use count is zero
Supply regulators are disabled only when the last
reference count is removed on the child regulator
(the use count goes from 1 to 0). This patch changes
the behaviour of enable so the supply regulator is
enabled only when the use count of the child
regulator goes from 0 to 1.

Signed-off-by: Bengt Jonsson <bengt.g.jonsson@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:00 +00:00
Mark Brown 02fa3ec01a regulator: Add basic trace facilities
Provide some basic trace facilities to the regulator API. We generate
events on regulator enable, disable and voltage setting over the actual
hardware operations (which are assumed to be the expensive ones which
require interaction with the actual device). This is intended to facilitate
debug of the performance and behaviour with consumers allowing unified
traces to be generated including the regulator operations within the
context of the other components of the system.

For enable we log the explicit delay for the voltage ramp separately to
the interaction with the hardware to highlight the time consumed in I/O.
We should add a similar delay for voltage changes, though there the
relatively small magnitude of the changes in the context of the I/O
costs makes it much less critical for most regulators.

Only hardware interactions are currently traced as the primary focus is
on the performance and synchronisation of actual hardware interactions.
Additional tracepoints for debugging of the logical operations can be
added later if required.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:00 +00:00
Mark Brown 3a93f2a9f4 regulator: Report actual configured voltage to set_voltage()
Change the interface used by set_voltage() to report the selected value
to the regulator core in terms of a selector used by list_voltage().
This allows the regulator core to know the voltage that was chosen
without having to do an explict get_voltage(), which would be much more
expensive as it will generally access hardware.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:32:59 +00:00
Mattias Wallin 63cee94614 regulator: lock supply in regulator enable
This patch add locks around regulator supply enable.

Signed-off-by: Mattias Wallin <mattias.wallin@stericsson.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:32:59 +00:00
Randy Dunlap 06c63f9396 regulator: fix kernel-doc for set_consumer_device_supply
Fix kernel-doc warning for set_consumer_device_supply():

Warning(drivers/regulator/core.c:912): missing initial short description on line:
 * set_consumer_device_supply: Bind a regulator to a symbolic supply

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc:	Liam Girdwood <lrg@slimlogic.co.uk>
Cc:	Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30 15:13:25 +00:00
Bengt Jonsson f3c18a87f3 regulator: enable supply regulator only when use count is zero
Supply regulators are disabled only when the last
reference count is removed on the child regulator
(the use count goes from 1 to 0). This patch changes
the behaviour of enable so the supply regulator is
enabled only when the use count of the child
regulator goes from 0 to 1.

Signed-off-by: Bengt Jonsson <bengt.g.jonsson@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30 15:13:25 +00:00
Mattias Wallin 3aa713e76e regulator: lock supply in regulator enable
This patch add locks around regulator supply enable.

Signed-off-by: Mattias Wallin <mattias.wallin@stericsson.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30 15:13:25 +00:00
Axel Lin 7727da22e8 regulator: Return proper error for regulator_register()
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30 15:13:25 +00:00
Axel Lin e36c1df8e1 regulator: Ensure enough delay time for enabling regulator
Integer division will truncate the result, this patch ensures we have
enough delay time for enabling regulator.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30 15:13:25 +00:00
Axel Lin aa7a74040a regulator: Remove a redundant device_remove_file call in create_regulator
We already have device_remove_file() in error path,
no need to call it before goto link_name_err.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30 15:13:25 +00:00
Mattias Wallin b12a1e29af regulator: regulator disable supply fix
This patch fixes a disable failure when regulator supply is used.
A while loop in regulator disable checks for supply pointer != NULL
but the pointer is not always updated, resulting in the while loop
running too many times causing a disable failure.

Signed-off-by: Mattias Wallin <mattias.wallin@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30 15:13:25 +00:00
Jeffrey Carlyle 8cbf811dfd regulator: avoid deadlock when disabling regulator with supply
I have a regulator A that sets regulator B as its supply. When I call
set_supply to add B as the supply for A, regulator A gets added to the
supply_list for regulator B.

When I call regulator_disable(A), I end up with a call chain like this:

regulator_disable(A)
> mutex_lock(A)
> _regulator_disable(A)
>> _regulator_disable(B)
>>> _notifier_call_chain(B)
>>>> mutex_lock(A)

Which results in dead lock since we are trying to acquire the mutex lock
for regulator A which we already hold.

This patch addresses this issue by moving the call to disable regulator
B outside of the lock aquired inside the initial call to
regulator_disable.

This change also addresses the issue of not acquiring the mutex for
regulator B before calling _regulator_disable(B).

Signed-off-by: Jeffrey Carlyle <jeff.carlyle@motorola.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-10-28 22:40:31 +01:00
Mark Brown 688fe99a43 regulator: Add option for machine drivers to enable the dummy regulator
Allow machine drivers to explicitly enable the use of the dummy regulator,
enabling simpler support for systems with only a few specific supplies
visible to software.

It is strongly recommended that this is not used on systems with
substantial software control over their PMICs, for maximum functionality
constrints should be as fully specified as possible.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-10-28 22:40:31 +01:00
Cyril Chemparathy e4a6376b3b regulator: fix typo in current units
This patch fixes a typo that incorrectly reports mA numbers as uA.

Signed-off-by: Cyril Chemparathy <cyril@ti.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-10-02 12:50:31 +01:00
Vasiliy Kulikov ad7725cb43 regulator: fix device_register() error handling
If device_register() fails then call put_device().
See comment to device_register.

Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-10-02 12:50:30 +01:00
Guenter Roeck 068a2782f5 regulator: Remove owner field from attribute initialization in regulator core driver
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-05 13:53:35 -07:00
Sundar R Iyer 500b4ac90d regulator: return set_mode is same mode is requested
On Mon, 2010-05-17 at 17:34 +0200, Mark Brown wrote:
> This doesn't seem like the right error handling - if the driver has a
> set_mode() you'd *expect* it to have a get_mode() but there's no need
> for it to be a strict requirement.
True. In such a case, even a valid request would be lost! So now
in the updated patch:
 - check if get_mode is present to avoid oops;
 - if get_mode is not present, proceed anyways for the request.

Here is the updated patch:

>From bad0d5eb51ef84be5b100e3dd0f5a590ea0529b6 Mon Sep 17 00:00:00 2001
From: Sundar R Iyer <sundar.iyer@stericsson.com>
Date: Fri, 14 May 2010 15:14:17 +0530
Subject: [PATCH 1/1] regulator: return set_mode when same mode is requested

save I/O costs by returning when the same mode is
requested for the regulator

Cc: Liam Girdwood <lrg@slimlogic.co.uk>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Sundar R Iyer <sundar.iyer@stericsson.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-05-25 10:16:02 +01:00
Jani Nikula d4033b54fc regulator: simplify regulator_register() error handling
Simply remove all consumer supplies for the regulator on errors. Remove
unset_consumer_device_supply() which is no longer used.

Signed-off-by: Jani Nikula <ext-jani.1.nikula@nokia.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-05-25 10:16:01 +01:00
Jani Nikula 47bd53f0e8 regulator: fix unset_regulator_supplies() to remove all matches
Remove all matching consumer supplies, not just the first, to not leave
dangling pointers.

Signed-off-by: Jani Nikula <ext-jani.1.nikula@nokia.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-05-25 10:16:01 +01:00
Jani Nikula 23b5cc2ab6 regulator: prevent registration of matching regulator consumer supplies
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

Pointer comparison is not sufficient for non-NULL device name matching,
so use strcmp(). Otherwise the semantics remain the same.

Signed-off-by: Jani Nikula <ext-jani.1.nikula@nokia.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-05-25 10:16:01 +01:00
Mark Brown 0178f3e28e regulator: Allow regulator-regulator supplies to be specified by name
When one regulator supplies another allow the relationship to be specified
using names rather than struct regulators, in a similar manner to that
allowed for consumer supplies. This allows static configuration at compile
time, reducing the need for dynamic init code.

Also change the references to LINE supply to be system supply since line
is sometimes used for actual supplies and therefore potentially confusing.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-05-25 10:16:01 +01:00
Jiri Kosina 6c9468e9eb Merge branch 'master' into for-next 2010-04-23 02:08:44 +02:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Ameya Palande 4f26a2abe1 regulator: Get rid of lockdep warning
WARNING: at kernel/lockdep.c:2706 sysfs_add_file_mode+0x4c/0xa8()

Difference between v1 and v2:
Moved sysfs_attr_init() call as first one to access the structure.

Signed-off-by: Ameya Palande <ameya.palande@nokia.com>
CC: Liam Girdwood <lrg@slimlogic.co.uk>
CC: Mark Brown <broonie@opensource.wolfsonmicro.com>
CC: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-03-22 19:44:44 +00:00
Thomas Weber 8839316121 Fix typos in comments
[Ss]ytem => [Ss]ystem
udpate => update
paramters => parameters
orginal => original

Signed-off-by: Thomas Weber <swirl@gmx.li>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-03-16 11:47:56 +01:00
Mark Brown 34abbd68ef regulator: Provide optional dummy regulator for consumers
In order to ease transitions with drivers are boards start using regulators
provide an option to cause all regulator_get() calls to succeed, with a
dummy always on regulator being supplied where one has not been configured.
A warning is printed whenever the dummy regulator is used to aid system
development.

This regulator does not implement any regulator operations but will allow
simple consumers which only do enable() and disable() calls to run. It
is kept separate from the fixed voltage regulator to avoid Kconfig
confusion on the part of users when it is extended to allow boards to
explicitly use the dummy regulator to simplify cases where the majority
of supplies are from fixed regulators without software control.

This option is currently only effective for systems which do not specify
full constriants. If required an override could also be provided to allow
these systems to use the dummy regulator, though it is likely that
unconfigured supplies on such systems will lead to error due to
regulators being powered down more aggressively when not in use.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-03-03 14:49:26 +00:00
Mark Brown 9a7f6a4c6e regulator: Assume regulators are enabled if they don't report anything
If a regulator driver does not provide a way to query if the driver is
enabled then assume that it is enabled.  This is very likely to reflect
the actual state is more useful for callers than reporting an error.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-03-03 14:49:26 +00:00
Mark Brown 31aae2beeb regulator: Allow regulators to specify the time taken to ramp on enable
Regulators may sometimes take longer to enable than the control operation
used to do so, either because the regulator has ramp rate control used to
limit inrush current or because the control operation is very fast (GPIO
being the most common example of this).  In order to ensure that consumers
do not rely on the regulator before it is enabled provide an enable_time()
operation and have the core delay for that time before returning to the
caller.

This is implemented as a function since the ramp rate may be specified in
voltage per unit time and therefore the time depend on the configuration.
In future it would be desirable to allow the bulk operations to run the
delays for multiple enables in parallel but this is not currently supported.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2010-03-03 14:49:23 +00:00
Mark Brown 84b6826306 regulator: Add notifier event on regulator disable
The intended use case is for drivers which disable regulators to save
power but need to do some work to restore the hardware state when
restarting.  If the supplies are not actually disabled due to board
limits or sharing with other active devices this notifier allows the
driver to avoid unneeded reinitialisation, particularly when used with
runtime PM.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2010-03-03 14:49:23 +00:00
Mark Brown 973e9a2795 regulator: Fix display of null constraints for regulators
If the regulator constraints are empty and there is no voltage
reported then nothing will be added to the text displayed for the
constraints, leading to random stack data being printed. This is
unlikely to happen for practical regulators since most will at
least report a voltage but should still be fixed.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@kernel.org
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-02-12 11:19:57 +00:00
Lars-Peter Clausen eb143ac1b9 regulator: Fix unbalanced disables/enables in regulator_bulk_{enable,disable} error path
Currently it is possible for regulator_bulk_{enable,disable} operations to
generate unbalanced regulator_{disable,enable} calls in its error path.
In case of an error only those regulators of the bulk operation which actually
had been enabled/disabled should get their original state restored.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-12-17 10:27:28 +00:00
Stefan Roese fa2984d469 regulator: core.c: Small coding style cleanup (indentation fixup)
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Liam Girdwood <lrg@slimlogic.co.uk>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-12-17 10:27:27 +00:00
Mark Brown 638f85c54f regulator: Handle regulators without suspend mode configuration
Since some regulators in the system may not support suspend mode
configuration we need to allow some regulators to have a missing
suspend mode configuration. Do this by requiring that disabled
regulators are explicitly flagged and then skip over regulators
that have no state specified.

Try to avoid surprises by warning the if we could set the state
but no configuration is provided.  This also ensures that an all
zeros configuration generates a warning rather than silently
disabling the regulator.

Reported-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-12-17 10:27:25 +00:00
Mark Brown 1083c39346 regulator: Factor out regulator name pretty printing
Some of the regulator API functions have code to allow the machine
constraints to override the device supplied name for the regulator
in the constraints in order to help tie logging to supplies on the
board and disambiguate when there is more than one regulator chip
in the system. Factor this code out into a new rdev_get_name()
function and use it throughout the regulator API so that we always
use the same name.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-12-17 10:27:24 +00:00
Mark Brown 8f031b48cd regulator: Display actual settings with constraints
When voltage or current constraints are either missing or specify
a range display the actual setting along with the constraints if
we can. This can aid debugging of configuration problems.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-12-17 10:27:24 +00:00
Mark Brown af5866c9cd regulator: Also lift apply_uV into machine_constraints_voltage()
It makes sense to do all the voltage configuration in the one split
out function.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-12-17 10:27:24 +00:00
Mark Brown e79055d62e regulator: Factor out voltage constraint setup
This allows constraints to take effect on regulators that support
voltage setting but for which the board does not specify a voltage
range (for example, because it is fixed correctly at system startup).

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-12-17 10:27:23 +00:00
Mark Brown 5b30762773 regulator: Report error codes for bulk operations
If we're going to log an error we may as well log what the error
code that we're failing on is.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-12-17 10:27:23 +00:00
Mark Brown 60ef66fcf4 regulator: Handle missing constraints in _regulator_disable()
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-11-16 09:57:16 +00:00
Linus Walleij a7433cff9e REGULATOR Handle positive returncode from enable
This makes _regulator_enable() properly handle the case where
a regulator is already on when you try to enable it. Currently
it will erroneously handle positive return values as an error.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-09-22 13:32:43 +01:00
Mark Brown 9a2372fa7a regulator: regulator_enable() permission checking
The regulator_enable() code wasn't actually checking that the
machine constraints had given permission to enable the regulator.
Add code to do that, but only if the regulator is not already on
due to something like always_on or being left on at startup since
in those cases there's no physical change being introduced and the
constraint wouldn't make any sense.

Also add matching code for disable(). We need to do less there since
either regulator_enable() should have succeeded first or the board
setup makes no sense.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-09-22 13:32:41 +01:00
Mark Brown 9332546fe8 regulator: Push locking for regulator_is_enabled() out
Allows use by more of the internal regulator API code.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-09-22 13:32:40 +01:00
Mark Brown f25e0b4fcc regulator: Check for constraints in regulator_init_complete()
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-09-22 13:32:40 +01:00
Mark Brown b39480ac37 regulator: Check for constraints before using them for name
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-09-22 13:32:40 +01:00
Mark Brown 9ed2099edc regulator: Fix support for deviceless supply mappings
The patch to add support for looking up consumers by device name
had the side effect of causing us to require a device which is
at best premature since at least cpufreq still operates outside
the device model. Remove that requirement.

Reported-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-09-22 13:32:39 +01:00
Mark Brown 6bf87d17c9 regulator: Warn when unregistering an in-use regulator
We're probably going to start oopsing fairly soon after this happens.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-09-22 13:32:39 +01:00
Mark Brown a7a1ad9066 regulator: Add regulator voltage range check API
Simplify checking of support for voltage ranges by providing an API which
wraps the existing count and list operations.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-09-22 13:32:38 +01:00
Mark Brown 5ffbd136e6 regulator: Add regulator_get_exclusive() API
Some consumers require complete control of the regulator and can't
tolerate sharing it with other consumers, most commonly because they need
to have the regulator actually disabled so can't have other consumers
forcing it on. This new regulator_get_exclusive() API call allows these
consumers to explicitly request this, documenting the assumptions that
they are making.

In order to simplify coding of such consumers the use count for regulators
they request is forced to match the enabled state of the regulator when
it is requested. This is not possible for consumers which can share
regulators due to the need to keep track of the ownership of use counts.

A new API call is used rather than an additional argument to the existing
regulator_get() in order to avoid merge headaches with driver code in
other trees.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-09-22 13:32:38 +01:00
Mark Brown 40f9244f4d regulator: Allow consumer supplies to be set up with dev_name()
Follow the approach suggested by Russell King and implemented by him in
the clkdev API and allow consumer device supply mapings to be set up
using the dev_name() for the consumer instead of the struct device.
In order to avoid making existing machines instabuggy and creating merge
issues the use of struct device is still supported for the time being.

This resolves problems working with buses such as I2C which make the
struct device available late providing that the final device name is
known, which is the case for most embedded systems with fixed setups.

Consumers must still use the struct device when calling regulator_get().

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-09-22 13:32:36 +01:00
Mark Brown be721979dd regulator: Provide mode to status conversion function
This is useful for implementing get_status() in terms of get_mode().

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2009-09-17 09:47:05 +02:00
Mark Brown 3e59091828 regulator: Fix default constraints for fixed voltage regulators
Default voltage constraints were being provided for fixed voltage
regulator where board constraints were not provided but these constraints
used INT_MIN as the default minimum voltage which is not a valid value
since it is less than zero. Use 1uV instead.

Also set the default values we set in the constraints themselves since
otherwise the max_uV constraint we determine will not be stored in the
actual constraint strucutre and will therefore not be used.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-04-28 18:58:08 +01:00
Paul Walmsley 53032dafc6 regulator core: fix double-free in regulator_register() error path
During regulator registration, any error after device_register() will
cause a double-free on the struct regulator_dev 'rdev'.  The bug is in
drivers/regulator/core.c:regulator_register():

...
scrub:
	device_unregister(&rdev->dev);
clean:
	kfree(rdev);                           <---
	rdev = ERR_PTR(ret);
	goto out;
...

device_unregister() calls regulator_dev_release() which frees rdev.  The
subsequent kfree corrupts memory and causes some OMAP3 systems to oops on
boot in regulator_get().

Applies against 2.6.30-rc3.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-04-28 18:58:07 +01:00
Diego Liziero cd78dfc6c6 drivers/regulator: fix when type is different from REGULATOR_VOLTAGE or REGULATOR_CURRENT
When regulator_desc->type is something different from REGULATOR_VOLTAGE or REGULATOR_CURRENT
the if should probably return ERR_PTR(-EINVAL)

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

@@ expression E; constant C; @@
(
- !E == C
+ E != C
)

Signed-off-by: Diego Liziero <diegoliz@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-04-28 18:58:07 +01:00
Dan Carpenter 036de8efae unreachable code in drms_uA_update()
I removed the extra semi-colon and indented the return statement.

The unreachable code was found by smatch (http://repo.or.cz/w/smatch.git).
The patch was compile tested.

regards,
dan carpenter

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-04-28 18:58:06 +01:00
Mark Brown ca7255614e regulator: Support disabling of unused regulators by machines
At present it is not possible for machine constraints to disable
regulators which have been left on when the system starts, for example
as a result of fixed default configurations in hardware. This means that
power may be wasted by these regulators if they are not in use.

Provide intial support for this with a late_initcall which will disable
any unused regulators if the machine has enabled this feature by calling
regulator_has_full_constraints(). If this has not been called then print
a warning to encourage users to fully specify their constraints so that
we can change this to be the default behaviour in future.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-03-31 09:56:29 +01:00
Mark Brown 50f075963f regulator: Don't increment use_count for boot_on regulators
Don't set use_count for regulators that are enabled at boot since this
stops the supply being disabled by well-behaved consumers which do
balanced enables and disabled. Any consumers which don't do disables
which are not matched by enables are unable to share regulators - shared
regulators are the common case so the API should facilitate them.

Consumers that want to disable regulators that are enabled when they
start have two options:

 - Do a regulator_enable() prior to the disable to bring the use count
   in sync with the hardware state; this will ensure that if the
   regulator was enabled by another driver then this consumer will play
   nicely with it.
 - Use regulator_force_disable(); this explicitly bypasses any checks
   done by the core and documents the inability of the driver to share
   the supply.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-03-31 09:56:29 +01:00
David Brownell cd94b50530 regulator: refcount fixes
Fix some refcounting issues in the regulator framework, supporting
regulator_disable() for regulators that were enabled at boot time
via machine constraints:

 - Update those regulators' usecounts after enabling, so they
   can cleanly be disabled at that level.

 - Remove the problematic per-consumer usecount, so there's
   only one level of enable/disable.

Buggy consumers could notice different bug symptoms.  The main
example would be refcounting bugs; also, any (out-of-tree) users
of the experimental regulator_set_optimum_mode() stuff which
don't call it when they're done using a regulator.

This is a net minor codeshrink.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-03-31 09:56:28 +01:00
Mark Brown 1dc60343f8 regulator: Don't warn if we failed to get a regulator
The consumer can print a message if required, some consumers may have
optional regulators and wish to downgrade the logging for them or ignore
their absence.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-03-31 09:56:28 +01:00
Mark Brown cacf90f24e regulator: Allow boot_on regulators to be disabled by clients
Rather than incrementing the reference count for boot_on regulators
(which prevents them being disabled later on) simply force the
regulator to be enabled when applying the constraints. Previously
boot_on was essentially equivalent to always_on.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-03-31 09:56:27 +01:00
Mark Brown 3e2b9abda5 regulator: Don't warn on omitted voltage constraints
Specifying voltage constraints is optional (and only needed if the
consumer is allowed to change the voltage) so don't complain unless
a voltage has been specified.

Also avoid surprises with a dangling else while we're here.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-03-31 09:56:26 +01:00
David Brownell 4367cfdc7c regulator: enumerate voltages (v2)
Add a basic mechanism for regulators to report the discrete
voltages they support:  list_voltage() enumerates them using
selectors numbered from 0 to an upper bound.

Use those methods to force machine-level constraints into bounds.
(Example:  regulator supports 1.8V, 2.4V, 2.6V, 3.3V, and board
constraints for that rail are 2.0V to 3.6V ... so the range of
voltages is then 2.4V to 3.3V on this board.)

Export those voltages to the regulator consumer interface, so for
example regulator hooked up to an MMC/SD/SDIO slot can report the
actual voltage options available to cards connected there.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-03-31 09:56:24 +01:00
Mark Brown a308466c24 regulator: Allow regulators to set the initial operating mode
This is useful when wishing to run in a fixed operating mode that isn't
the default.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-03-31 09:56:24 +01:00
Mark Brown fe203ddfa5 regulator: Suggest use of datasheet supply or pin names for consumers
Update the documentation to suggest the use of datasheet names for
the supplies requested by regulator consumers. Doing this makes it
easier to tie the design for a given platform up with the requirements
of the driver for a consumer.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-03-31 09:56:23 +01:00
Mike Rapoport 0f1d747bfa regulator: add unset_regulator_supplies to fix regulator_unregister
Currently regulator_unregister does not clear regulator <--> consumer
mapping.
This patch introduces unset_regulator_supplies that clear the map.

Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-03-31 09:56:23 +01:00
Mark Brown 1fa9ad52b0 regulator: Hoist struct regulator_dev out of core to fix notifiers
Commit 872ed3fe176833f7d43748eb88010da4bbd2f983 caused regulator drivers
to take the struct regulator_dev lock themselves which requires that the
struct be visible to them. Band aid this by making the struct visible.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-03-31 09:56:22 +01:00
Mark Brown 0527100fd1 regulator: Pass regulator init data as explict argument when registering
Rather than having the regulator init data read from the platform_data
member of the struct device that is registered for the regulator make
the init data an explict argument passed in when registering. This
allows drivers to use the platform data for their own purposes if they
wish.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-03-31 09:56:21 +01:00
Jonathan Cameron b136fb4463 Regulator: Push lock out of _notifier_call_chain + add voltage change event.
Regulator: Push lock out of _notifier_call_chain and into caller functions
(side effect of fixing deadlock in regulator_force_disable)
+ Add a voltage changed event.
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-03-31 09:56:20 +01:00
David Brownell 853116a105 regulator: add get_status()
Based on previous LKML discussions:

 * Update docs for regulator sysfs class attributes to highlight
   the fact that all current attributes are intended to be control
   inputs, including notably "state" and "opmode" which previously
   implied otherwise.

 * Define a new regulator driver get_status() method, which is the
   first method reporting regulator outputs instead of inputs.
   It can report on/off and error status; or instead of simply
   "on", report the actual operating mode.

For the moment, this is a sysfs-only interface, not accessible to
regulator clients.  Such clients can use the current notification
interfaces to detect errors, if the regulator reports them.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-03-31 09:56:20 +01:00
David Brownell 6001e13c5f regulator: catch some registration errors
Prevent registration of duplicate "struct regulator" names.
They'd be unavailable, and clearly indicate something wrong.

[Edited to remove check for NULL consumer device until we have a
solution for things like cpufreq -- broonie]

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-01-08 20:10:34 +00:00
Mark Brown cf7bbcdf4d regulator: Fix some kerneldoc rendering issues
There are some minor textual changes in here as well, mostly to enable()
and disable() but the primary goal of these changes is to fix
misrenderings of the kerneldoc documentation for the regulator API.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-01-08 20:10:33 +00:00
Mark Brown c8e7e4640f regulator: Add missing kerneldoc
This is only the documentation that the kerneldoc system warns about.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-01-08 20:10:33 +00:00
Mark Brown 69279fb9a9 regulator: Clean up kerneldoc warnings
Remove kerneldoc warnings that don't relate to missing documentation,
mostly by renaming parameters in the documentation to match their
actual names.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-01-08 20:10:33 +00:00
Mark Brown 8dc5390d4f regulator: Remove extraneous kerneldoc annotations
Some of the internal structures have no kerneldoc but the ** at the start
of the comment marking them for documentation.  Remove the annotation
until some is added.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-01-08 20:10:32 +00:00
Mike Rapoport 74f544c1fc regulator: move set_machine_constraints after regulator device initialization
Calling set_machine_constraints before regulator device initialization
causes crash when constraints have apply_uV set.

Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-01-08 20:10:31 +00:00
David Brownell 7ad68e2f97 regulator: sysfs attribute reduction (v2)
Clean up the sysfs interface to regulators by only exposing the
attributes that can be properly displayed.  For example: when a
particular regulator method is needed to display the value, only
create that attribute when that method exists.

This cleaned-up interface is much more comprehensible.  Most
regulators only support a subset of the possible methods, so
often more than half the attributes would be meaningless.  Many
"not defined" values are no longer necessary.  (But handling
of out-of-range values still looks a bit iffy.)

Documentation is updated to reflect that few of the attributes
are *always* present, and to briefly explain why a regulator may
not have a given attribute.

This adds object code, about a dozen bytes more than was removed
by the preceding patch, but saves a bunch of per-regulator data
associated with the now-removed attributes.  So there's a net
reduction in memory footprint.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-01-08 20:10:30 +00:00
David Brownell 4fca9545d1 regulator: code shrink (v2)
Shrink regulator core by removing duplication in attribute printing
and probe() cleanup paths.  Saves about 340 bytes (object) on ARM.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-01-08 20:10:30 +00:00
David Brownell e573520b17 regulator: improved mode error checks
Minor bugfixes in handling of regulator modes:

 - have the routine verifying regulator modes check against
   the set of legal modes (!);

 - have regulator_set_optimum_mode() verify the return value
   of regulator_ops.get_optimum_mode(), like drms_uA_update();

 - one call to regulator_ops.set_mode() treated zero as a
   failure code; make this consistent with other callers.

Both regulator_set_mode() and regulator_set_optimum_mode() now
require valid_ops_mask to include REGULATOR_CHANGE_MODE; that
seems like a bugfix too.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-01-08 20:10:30 +00:00
David Brownell 412aec6105 regulator: enable/disable refcounting
Make the <linux/regulator.h> framework treat enable/disable call
pairs like the <linux/clk.h> and <linux/interrupt.h> frameworks do:
they're refcounted, so that different parts of a driver don't need
to put work into coordination that frameworks normally handle.
It's a minor object code shrink.

It also makes the regulator_is_disabled() kerneldoc say what it's
actually returning:  return value is not a refcount, and may report
an error (e.g. I/O error from I2C).

It also fixes some minor regulator_put() goofage:  removing unlocked
access to the enable state.  (But still not making regulator put/get
match the refcounting pattern they invoke.)

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-01-08 20:10:29 +00:00
Kay Sievers 812460a927 regulator: struct device - replace bus_id with dev_name(), dev_set_name()
This patch is part of a larger patch series which will remove
the "char bus_id[20]" name string from struct device. The device
name is managed in the kobject anyway, and without any size
limitation, and just needlessly copied into "struct device".

To set and read the device name dev_name(dev) and dev_set_name(dev)
must be used. If your code uses static kobjects, which it shouldn't
do, "const char *init_name" can be used to statically provide the
name the registered device should have. At registration time, the
init_name field is cleared, to enforce the use of dev_name(dev) to
access the device name at a later time.

We need to get rid of all occurrences of bus_id in the entire tree
to be able to enable the new interface. Please apply this patch,
and possibly convert any remaining remaining occurrences of bus_id.

We want to submit a patch to -next, which will remove bus_id from
"struct device", to find the remaining pieces to convert, and finally
switch over to the new api, which will remove the 20 bytes array
and does no longer have a size limitation.

Thanks,
Kay

From: Kay Sievers <kay.sievers@vrfy.org>
Subject: regulator: struct device - replace bus_id with dev_name(), dev_set_name()

Cc: Liam Girdwood <lrg@slimlogic.co.uk>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-Off-By: Kay Sievers <kay.sievers@vrfy.org>

Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-01-08 20:10:29 +00:00
Mark Brown bc558a60b5 regulator: Export regulator name via sysfs
Provide a new file 'name' in the regulator sysfs class with a human
readable name for the regulator for use in applications.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-13 21:51:53 +01:00
Mark Brown e5fda26c7e regulator: Enable regulators marked as always_on
If the machine constraints mark a regulator as always_on but this was
not done by the bootloader then enable the regulator when applying
constraints.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-13 21:51:51 +01:00
Mark Brown e06f5b4fea regulator: Additional diagnostics for machine constraints
Try to find a human readable name for the regulator we're failing on and
print a specific diagnostic when we fail to set the suspend state.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-13 21:51:51 +01:00
Mark Brown 46fabe1edd regulator: check for init_data on registration
Since it is now mandatory to supply constraints via init_data on device
registration check for that when registering, saving us from oopsing
later on.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-13 21:51:51 +01:00
Liam Girdwood a5766f11cf regulator: core - Rework machine API to remove string based functions.
This improves the machine level API in order to configure
regulator constraints and consumers as platform data and removes the
old string based API that required several calls to set up each regulator.

The intention is to create a struct regulator_init_data, populate
it's fields with constraints, consumers devices, etc and then register
the regulator device from board.c in the standard Linux way.

e.g. regulator LDO2 (supplying codec and sim) platform data.

/* regulator LDO2 consumer devices */
static struct regulator_consumer_supply ldo2_consumers[] = {
{
	.dev	= &platform_audio_device.dev,
	.supply	= "codec_avdd",
},
{
	.dev	= &platform_sim_device.dev,
	.supply	= "sim_vcc",
}
};

/* regulator LDO2 constraints  */
static struct regulator_init_data ldo2_data = {
	.constraints = {
		.min_uV = 3300000,
		.max_uV = 3300000,
		.valid_modes_mask = REGULATOR_MODE_NORMAL,
		.apply_uV = 1,
	},
	.num_consumer_supplies = ARRAY_SIZE(ldo2_consumers),
	.consumer_supplies = ldo2_consumers,
};

/* machine regulator devices with thier consumers and constraints */
static struct platform_device wm8350_regulator_devices[] = {
{
	.name = "wm8350-regulator",
	.id = WM8350_LDO_2,
	.dev = {
		.platform_data = &ldo2_data,
	},
},
};

Changes in detail:-

  o Removed all const char* regulator config functions in machine API.
  o Created new struct regulator_init_data to contain regulator
    machine configuration constraints and consmuers.
  o Changed set_supply(), set_machine_constraints(),
    set_consumer_device_supply() to remove their string identifier
    parameters. Also made them static and moved functions nearer top of
    core.c.
  o Removed no longer used inline func to_rdev()
  o Added regulator_get_init_drvdata() to retrieve init data.
  o Added struct device* as parameter to regulator_register().
  o Changed my email address.

Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-13 21:51:50 +01:00
Liam Girdwood 414c70cb91 regulator: regulator framework core
This adds the regulator framework core.

This framework is designed to provide a generic interface to voltage
and current regulators within the Linux kernel. It's intended to
provide voltage and current control to client or consumer drivers and
also provide status information to user space applications through a
sysfs interface.

The intention is to allow systems to dynamically control regulator
output in order to save power and prolong battery life. This applies
to both voltage regulators (where voltage output is controllable) and
current sinks (where current output is controllable).

This framework safely compiles out if not selected so that client
drivers can still be used in systems with no software controllable
regulators.

Signed-off-by: Liam Girdwood <lg@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2008-07-30 10:10:21 +01:00