linux-stable.git/drivers/regulator/core.c, branch linux-3.14.y

regulator: core: fix constraints output buffer

2015-08-03T16:29:51+00:00

commit a7068e3932eee8268c4ce4e080a338ee7b8a27bf upstream.

The buffer for condtraints debug isn't big enough to hold the output
in all cases. So fix this issue by increasing the buffer.

Signed-off-by: Stefan Wahren 
Signed-off-by: Mark Brown 
Signed-off-by: Greg Kroah-Hartman

regulator: core: Fix enable GPIO reference counting

2015-03-26T14:06:56+00:00

commit 29d62ec5f87fbeec8413e2215ddad12e7f972e4c upstream.

Normally _regulator_do_enable() isn't called on an already-enabled
rdev.  That's because the main caller, _regulator_enable() always
calls _regulator_is_enabled() and only calls _regulator_do_enable() if
the rdev was not already enabled.

However, there is one caller of _regulator_do_enable() that doesn't
check: regulator_suspend_finish().  While we might want to make
regulator_suspend_finish() behave more like _regulator_enable(), it's
probably also a good idea to make _regulator_do_enable() robust if it
is called on an already enabled rdev.

At the moment, _regulator_do_enable() is _not_ robust for already
enabled rdevs if we're using an ena_pin.  Each time
_regulator_do_enable() is called for an rdev using an ena_pin the
reference count of the ena_pin is incremented even if the rdev was
already enabled.  This is not as intended because the ena_pin is for
something else: for keeping track of how many active rdevs there are
sharing the same ena_pin.

Here's how the reference counting works here:

* Each time _regulator_enable() is called we increment
  rdev->use_count, so _regulator_enable() calls need to be balanced
  with _regulator_disable() calls.

* There is no explicit reference counting in _regulator_do_enable()
  which is normally just a warapper around rdev->desc->ops->enable()
  with code for supporting delays.  It's not expected that the
  "ops->enable()" call do reference counting.

* Since regulator_ena_gpio_ctrl() does have reference counting
  (handling the sharing of the pin amongst multiple rdevs), we
  shouldn't call it if the current rdev is already enabled.

Note that as part of this we cleanup (remove) the initting of
ena_gpio_state in regulator_register().  In _regulator_do_enable(),
_regulator_do_disable() and _regulator_is_enabled() is is clear that
ena_gpio_state should be the state of whether this particular rdev has
requested the GPIO be enabled.  regulator_register() was initting it
as the actual state of the pin.

Fixes: 967cfb18c0e3 ("regulator: core: manage enable GPIO list")
Signed-off-by: Doug Anderson 
Signed-off-by: Mark Brown 
Signed-off-by: Greg Kroah-Hartman

regulator: Only enable disabled regulators on resume

2015-03-26T14:06:56+00:00

commit 0548bf4f5ad6fc3bd93c4940fa48078b34609682 upstream.

The _regulator_do_enable() call ought to be a no-op when called on an
already-enabled regulator.  However, as an optimization
_regulator_enable() doesn't call _regulator_do_enable() on an already
enabled regulator.  That means we never test the case of calling
_regulator_do_enable() during normal usage and there may be hidden
bugs or warnings.  We have seen warnings issued by the tps65090 driver
and bugs when using the GPIO enable pin.

Let's match the same optimization that _regulator_enable() in
regulator_suspend_finish().  That may speed up suspend/resume and also
avoids exposing hidden bugs.

[Use much clearer commit message from Doug Anderson]

Signed-off-by: Javier Martinez Canillas 
Signed-off-by: Mark Brown 
Signed-off-by: Greg Kroah-Hartman

regulator: core: fix race condition in regulator_put()

2015-02-06T06:35:51+00:00

commit 83b0302d347a49f951e904184afe57ac3723476e upstream.

The regulator framework maintains a list of consumer regulators
for a regulator device and protects it from concurrent access using
the regulator device's mutex lock.

In the case of regulator_put() the consumer is removed and regulator
device's parameters are updated without holding the regulator device's
mutex. This would lead to a race condition between the regulator_put()
and any function which traverses the consumer list or modifies regulator
device's parameters.
Fix this race condition by holding the regulator device's mutex in case
of regulator_put.

Signed-off-by: Ashay Jaiswal 
Signed-off-by: Mark Brown 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'regulator-v3.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator

2014-03-04T16:41:42+00:00

Pull regulator fixes from Mark Brown:
 "A couple of fixes here which ensure that regulators using the core
  support for GPIO enables work in all cases by ensuring that helpers
  are used consistently rather than open coding in places and hence not
  having GPIO support in some of them"

* tag 'regulator-v3.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
  regulator: core: Replace direct ops->disable usage
  regulator: core: Replace direct ops->enable usage

regulator: core: Replace direct ops->disable usage

2014-02-25T01:31:45+00:00

There are many places where ops->disable is called directly. Instead we
should use _regulator_do_disable() which also handles gpio regulators.

To be able to use the wrapper function from _regulator_force_disable(),
I moved the _notifier_call_chain() call from _regulator_do_disable() to
_regulator_disable(). This way, _regulator_force_disable() can use
different flags for _notifier_call_chain() without calling it twice.

Cc:  # 3.10+
Signed-off-by: Markus Pargmann 
Signed-off-by: Mark Brown

regulator: core: Replace direct ops->enable usage

2014-02-25T01:31:25+00:00

There are some direct ops->enable in the regulator core driver. This is
a potential issue as the function _regulator_do_enable() handles gpio
regulators and the normal ops->enable calls. These gpio regulators are
simply ignored when ops->enable is called directly.

One possible bug is that boot-on and always-on gpio regulators are not
enabled on registration.

This patch replaces all ops->enable calls by _regulator_do_enable.

[Handle missing enable operations -- broonie]

Cc:  # 3.10+
Signed-off-by: Markus Pargmann 
Signed-off-by: Mark Brown 

regulator: Handle invalid enable operation for always/boot on regulators

Signed-off-by: Mark Brown

Merge remote-tracking branch 'regulator/fix/core' into regulator-linus

2014-02-23T03:22:18+00:00

regulator: core: Change dummy supplies error message to a warning

2014-02-20T23:35:31+00:00

Change "dummy supplies not allowed" error message to warning instead, as this
is a just warning message with no change to the behavior.

[Added a CC to stable since some other bug fixes cause this to come up
more frequently on PCs which is how it was noticed -- broonie]

Signed-off-by: Shuah Khan 
Signed-off-by: Mark Brown 
Cc: stable@vger.kernel.org

regulator: core: Correct default return value for full constraints

2014-01-28T11:37:43+00:00

Once we have full constraints then all supply mappings should be known to
the regulator API. This means that we should treat failed lookups as fatal
rather than deferring in the hope of further registrations but this was
broken by commit 9b92da1f1205bd25 "regulator: core: Fix default return
value for _get()" which was targeted at DT systems but unintentionally
broke non-DT systems by changing the default return value.

Fix this by explicitly returning -EPROBE_DEFER from the DT lookup if we
find a property but no corresponding regulator and by having the non-DT
case default to -ENODEV when we have full constraints.

Fixes: 9b92da1f1205bd25 "regulator: core: Fix default return value for _get()"
Signed-off-by: Mark Brown 
Tested-by: Guenter Roeck 
Cc: stable@vger.kernel.org