Commit Graph

580 Commits

Author SHA1 Message Date
Chunyan Zhang
aa27bbc6c6
regulator: empty the old suspend functions
Regualtor suspend/resume functions should only be called by PM suspend
core via registering dev_pm_ops, and regulator devices should implement
the callback functions.  Thus, any regulator consumer shouldn't call
the regulator suspend/resume functions directly.

In order to avoid compile errors, two empty functions with the same name
still be left for the time being.

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-01-26 14:43:51 +00:00
Chunyan Zhang
72069f9957
regulator: leave one item to record whether regulator is enabled
The items "disabled" and "enabled" are a little redundant, since only one
of them would be set to record if the regulator device should keep on
or be switched to off in suspend states.

So in this patch, the "disabled" was removed, only leave the "enabled":
  - enabled == 1 for regulator-on-in-suspend
  - enabled == 0 for regulator-off-in-suspend
  - enabled == -1 means do nothing when entering suspend mode.

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-01-26 14:43:46 +00:00
Chunyan Zhang
c360a6df02
regulator: make regulator voltage be an array to support more states
Some regulator consumers would like to make the regulator device
keeping a voltage range output when the system entering into
suspend states.

Making regulator voltage be an array can allow consumers to set voltage
for normal state as well as for suspend states through the same code.

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-01-26 14:43:45 +00:00
Colin Ian King
0d5c8633b1
regulator: fix incorrect indentation of two assignment statements
Remove extraneous space to fix indentation on a couple of assignment
statements.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-12-07 14:04:43 +00:00
Mark Brown
02929a4478 Merge remote-tracking branches 'regulator/topic/cpcap', 'regulator/topic/da9063', 'regulator/topic/dt', 'regulator/topic/fan53555' and 'regulator/topic/ltc3589' into regulator-next 2017-09-04 17:45:42 +01:00
Tirupathi Reddy
c9ccaa0cac regulator: core: fix a possible race in disable_work handling
A race condition between queueing and processing the disable_work
instances results in having a work instance in the queue and the
deferred_disables variable of regulator device structure having a
value '0'. If no new regulator_disable_deferred() call later from
clients, the deferred_disables variable value remains '0' and hits
BUG() in regulator_disable_work() when the queued instance scheduled
for processing the work.

The race occurs as below:

	Core-0					     Core-1
	.....	       /* deferred_disables = 2 */   .....
	.....	       /* disable_work is queued */  .....
	.....					     .....
regulator_disable_deferred: 		regulator_disable_work:
   mutex_lock(&rdev->mutex);			     .....
   rdev->deferred_disables++;		             .....
   mutex_unlock(&rdev->mutex);			     .....
   queue_delayed_work(...)		    mutex_lock(&rdev->mutex);
	.....				    count =rdev->deferred_disables;
	.....				    rdev->deferred_disables = 0;
	.....					     .....
	.....				    mutex_unlock(&rdev->mutex);
	.....					     .....
	.....				    return;
	.....					     .....
	/* No new regulator_disable_deferred() calls from clients */
	/* The newly queued instance is scheduled for processing */
	.....					     .....
regulator_disable_work:
	.....
   mutex_lock(&rdev->mutex);
   BUG_ON(!rdev->deferred_disables); /* deferred_disables = 0 */

The race is fixed by removing the work instance that is queued while
processing the previous queued instance. Cancel the newly queued instance
from disable_work() handler just after reset the deferred_disables variable
to value '0'. Also move the work queueing step before mutex_unlock in
regulator_disable_deferred().

Also use mod_delayed_work() in the pace of queue_delayed_work() as
queue_delayed_work() always uses the delay requested in the first call
when multiple consumers call regulator_disable_deferred() close in time
and does not guarantee the semantics of regulator_disable_deferred().

Signed-off-by: Tirupathi Reddy <tirupath@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-07-20 13:22:29 +01:00
Rob Herring
7799167b7a regulator: Convert to using %pOF instead of full_name
Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-07-19 11:56:01 +01:00
Mark Brown
8d67f64f77 Merge remote-tracking branches 'regulator/topic/settle', 'regulator/topic/tps65910' and 'regulator/topic/tps65917' into regulator-next 2017-07-03 16:52:21 +01:00
Mark Brown
fcaa3167b2 Merge remote-tracking branch 'regulator/topic/core' into regulator-next 2017-07-03 16:52:16 +01:00
Haishan Zhou
dbc5595540 regulator: core: Fix size limit of supply_map
Now the debugfs file supply_map has a size limit PAGE_SIZE and the user
can not see the whole content of regulator_map_list when it is larger
than this limit.

This patch uses seq_file instead to make sure supply_map shows the full
information of regulator_map_list.

Signed-off-by: Haishan Zhou <zhssmail@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-30 12:56:42 +01:00
Tirupathi Reddy
2c2874b191 regulator: core: Fix voltage change propagations to supply regulators
Some regulators support get_voltage() and some support get_voltage_sel()
operations but currently we only propagate changes if the regulator has
a get_voltage() operation.  Also do this if we've got get_voltage_sel()

[Rewite commit message for clarity -- broonie]

Signed-off-by: Tirupathi Reddy <tirupath@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-28 20:39:36 +01:00
Charles Keepax
062171973e regulator: core: Prioritise consumer mappings over regulator name
Currently, when looking up a regulator supply, the regulator name
takes priority over the consumer mappings. As there are a lot of
regulator names that are in fairly common use (VDD, MICVDD, etc.) this
can easily lead to obtaining the wrong supply, when a system contains
two regulators that share a name.

The explicit consumer mappings contain much less ambiguity as they
specify both a name and a consumer device. As such prioritise those if
one exists and only fall back to the regulator name if there are no
matching explicit mappings.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-13 18:43:28 +01:00
Matthias Kaehlcke
3ffad468cf regulator: Allow for asymmetric settling times
Some regulators have different settling times for voltage increases and
decreases. To avoid a time penalty on the faster transition allow for
different settings for up- and downward transitions.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-05-17 10:49:25 +01:00
Mark Brown
81bc8e386f Merge remote-tracking branches 'regulator/topic/notifier', 'regulator/topic/pfuze100', 'regulator/topic/settle', 'regulator/topic/tps65132' and 'regulator/topic/twl6030' into regulator-next 2017-04-30 22:17:36 +09:00
Mark Brown
c93609ab39 regulator: core: Allow dummy regulators for supplies
Rather than just not resolving the supply when there is explicitly no
supply mapping fall through and allow a dummy supply to be substituted.
This fixes issues with constant retries reported by Dong Aisheng.

Signed-off-by: Mark Brown <broonie@kernel.org>
Tested-by: Dong Aisheng <aisheng.dong@nxp.com>
Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com>
2017-04-14 18:08:01 +01:00
Mark Brown
43fc99f293 regulator: core: Only propagate voltage changes to if it can change voltages
When we are propagating voltage changes to parent regulators don't
bother if the parent does not have permission to change voltages.  This
simplifies error checking in the function for cases where the regulator
lacks some of the voltage operations.

Reported-by: Dong Aisheng <aisheng.dong@nxp.com>
Tested-by: Dong Aisheng <aisheng.dong@nxp.com>
Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-04-14 18:07:51 +01:00
Laxman Dewangan
d6c1dc3f52 regulator: Add settling time for non-linear voltage transition
Some regulators (some PWM regulators) have the voltage transition
non-linear i.e. exponentially. On such cases, the settling time
for voltage transition can not be presented in the voltage-ramp-delay.

Add new property for non-linear voltage transition and handle this
in getting the voltage settling time.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-04-05 18:25:10 +01:00
Matthias Kaehlcke
fd08604555 regulator: core: Limit propagation of parent voltage count and list
Commit 26988efe11 ("regulator: core: Allow to get voltage count and
list from parent") introduces the propagation of the parent voltage
count and list for regulators that don't provide this information
themselves. The goal is to support simple switch regulators, however as
a side effect normal continuous regulators can leak details of their
supplies and provide consumers with inconsistent information.

Limit the propagation of the voltage count and list to switch
regulators.

Fixes: 26988efe11 ("regulator: core: Allow to get voltage count and
  list from parent")
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-03-29 12:49:38 +01:00
Tamara Diaconita
fffd113338 regulator: core: Fix kerneldoc comments
Remove the description for the non-existing 'ret' to fix the build warning:
./drivers/regulator/core.c:1467: warning:
Excess function parameter 'ret' description in 'regulator_dev_lookup'.
The description found for the return value is: @ret: 0 on success, -ENODEV
if lookup fails permanently, -EPROBE_DEFER if lookup could succeed in the future.

Signed-off-by: Tamara Diaconita <diaconita.tamara@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-03-29 11:35:32 +01:00
Harald Geyer
264b88c9e5 regulator: core: Add new notification for enabling of regulator
This is useful for devices, which need some time to start up, to help
the drivers track how long the supply has been up already. Ie whether
it can safely talk to the HW or needs to wait.

Signed-off-by: Harald Geyer <harald@ccbib.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-03-24 19:13:42 +00:00
Stephen Boyd
0630b61439 regulator: Mark supply_name const and duplicate it as such
The supply_name member of struct regulator can be const as we
don't change it in the regulator core. Furthermore, when we copy
the supply name we can use kstrdup_const() here to avoid a copy
if the name is in the ro data section.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-03-17 13:12:22 +00:00
Bartosz Golaszewski
b7cd1b1386 regulator: core: use snprintf() instead of scnprintf()
When creating the link to the device sysfs entry, the regulator core
calls scnprintf() and then checks if the returned value is greater or
equal than the buffer size.

The former can never happen as scnprintf() returns the number of bytes
that were actually written to the buffer, not the bytes that *would*
have been written.

Use the right function in this case: snprintf().

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-03-07 13:07:21 +01:00
Mark Brown
fad9cd45ed Merge remote-tracking branches 'regulator/topic/s2mpa01', 'regulator/topic/supplies' and 'regulator/topic/tps65217' into regulator-next 2017-02-19 16:40:41 +00:00
Mark Brown
401c42429c Merge remote-tracking branch 'regulator/topic/core' into regulator-next 2017-02-19 16:40:23 +00:00
Mark Brown
0fe3f971fc Merge remote-tracking branches 'regulator/fix/debugfs' and 'regulator/fix/tps65086' into regulator-linus 2017-02-19 16:40:22 +00:00
Javier Martinez Canillas
3827b64dba regulator: core: Resolve supplies before disabling unused regulators
After commit 66d228a2bf ("regulator: core: Don't use regulators as
supplies until the parent is bound"), input supplies aren't resolved
if the input supplies parent device has not been bound. This prevent
regulators to hold an invalid reference if its supply parent device
driver probe is deferred.

But this causes issues on some boards where a PMIC's regulator use as
input supply a regulator from another PMIC whose driver is registered
after the driver for the former.

In this case the regulators for the first PMIC will fail to resolve
input supplies on regulators registration (since the other PMIC wasn't
probed yet). And when the core attempts to resolve again latter when
the other PMIC registers its own regulators, it will fail again since
the parent device isn't bound yet.

This will cause some parent supplies to never be resolved and wrongly
be disabled on boot due taking them as unused.

To solve this problem, also attempt to resolve the pending regulators
input supplies before disabling the unused regulators.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-02-16 18:15:01 +00:00
Leonard Crestez
e42a46b6f5 regulator: Fix regulator_summary for deviceless consumers
It is allowed to call regulator_get with a NULL dev argument
(_regulator_get explicitly checks for it) but this causes an error later
when printing /sys/kernel/debug/regulator_summary.

Fix this by explicitly handling "deviceless" consumers in the debugfs code.

Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
2017-02-16 12:44:58 +00:00
Dmitry Torokhov
a4d7641fa7 regulator: core: simplify _regulator_get()
The code in _regulator_get() got a bit confusing over time, with control
flow jumping to a label from couple of places. Let's untangle it a bit by
doing the following:

1. Make handling of missing supplies and substituting them with dummy
regulators more explicit:

- check if we not have full constraints and refuse considering dummy
  regulators with appropriate message;

- use "switch (get_type)" to handle different types of request explicitly
  as well. "Normal" requests will get dummies, exclusive will not and
  will notify user about that; optional will fail silently.

2. Stop jumping to a label in the middle of the function but instead have
proper conditional flow. I believe jumps should be reserved for error
handling, breaking from inner loop, or restarting a loop, but not for
implementing normal conditional flow.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-02-08 18:29:05 +00:00
Dmitry Torokhov
163478dae0 regulator: core: have regulator_dev_lookup() return ERR_PTR-encoded errors
Instead of returning both regulator_dev structure as return value and
auxiliary error code in 'ret' argument, let's switch to using ERR_PTR
encoded values. This makes it more obvious what is going on at call sites.

Also, let's not unlock the mutex in the middle of a loop, but rather break
out and have single unlock path.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-02-05 17:36:40 +01:00
Dmitry Torokhov
d1642ea717 regulator: core: fix typo in regulator_bulk_disable()
"re-enable" was misspelled as "reename".

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-02-04 11:37:32 +01:00
Dmitry Torokhov
b8c77ff690 regulator: core: simplify regulator_bulk_force_disable()
There is no need to have two loops there, we can store error for subsequent
reporting.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-02-04 11:37:24 +01:00
Dmitry Torokhov
a8bd42a977 regulator: core: have _regulator_get() accept get_type argument
Instead of separate "exclusive" and "allow_dummy" arguments, that formed 3
valid combinations (normal, exclusive and optional) and an invalid one,
let's accept explicit "get_type", like we did in devm-managed code.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-02-04 11:31:52 +01:00
Dmitry Torokhov
7d245afa24 regulator: core: remove dead code in _regulator_get()
There is no point in assigning value to 'ret' before calling
regulator_dev_lookup() as it will clobber 'ret' anyway.

Also, let's explicitly return -PROBE_DEFER when try_module_get() fails,
instead of relying that earlier initialization of "regulator" carries
correct value.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-02-04 11:25:07 +01:00
Jon Hunter
66d228a2bf regulator: core: Don't use regulators as supplies until the parent is bound
When regulators are successfully registered, we check to see if the
regulator is a supply for any other registered regulator and if so
add the new regulator as the supply for the existing regulator(s).

Some devices, such as Power Management ICs, may register a series of
regulators when probed and there are cases where one of the regulators
may fail to register and defer the probing of the parent device. In this
case any successfully registered regulators would be unregistered so
that they can be re-registered at some time later when the probe is
attempted again. However, if one of the regulators that was registered
was added as a supply to another registered regulator (that did not
belong to the same parent device), then this supply regulator was
unregister again because the parent device is probe deferred, then a
regulator could be holding an invalid reference to a supply regulator
that has been unregistered. This will lead to a system crash if that
regulator is then used.

Although it would be possible to check when unregistering a regulator
if any other regulator in the system is using it as a supply, it still
may not be possible to remove it as a supply if this other regulator is
in use. Therefore, fix this by preventing any regulator from adding
another regulator as a supply if the parent device for the supply
regulator has not been bound and if the parent device for the supply
and the regulator are different. This will allow a parent device that is
registering regulators to be probe deferred and ensure that none of the
regulators it has registered are used as supplies for any other
regulator from another device.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-01-12 17:25:14 +00:00
Mark Brown
bed69721b6 Merge remote-tracking branches 'regulator/topic/arizona', 'regulator/topic/bypass', 'regulator/topic/error' and 'regulator/topic/fixed' into regulator-next 2016-12-12 12:17:24 +00:00
Mark Brown
6b46856246 Merge remote-tracking branch 'regulator/topic/core' into regulator-next 2016-12-12 12:17:23 +00:00
David Lechner
b2661e983f regulator: core: add newline in debug message
This adds a trailing newline to a debug message.

Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-12-05 11:31:30 +00:00
Charles Keepax
109c75afa1 regulator: core: Correct type of mode in regulator_mode_constrain
Every function handling the mode within the regulator core uses an unsigned
int for mode, except for regulator_mode_constrain. This patch changes the
type of mode within regulator_mode_constrain which fixes several instances
where we are passing pointers to unsigned ints then treating them as an int
within this function.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-11-30 17:44:16 +00:00
Axel Haslam
1b5b422164 regulator: core: Add new API to poll for error conditions
Regulator consumers can receive event notifications when
errors are reported to the driver, but currently, there is
no way for a regulator consumer to know when the error is over.

To allow a regulator consumer to poll for error conditions
add a new API: regulator_get_error_flags.

Signed-off-by: Axel Haslam <ahaslam@baylibre.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-11-04 12:15:25 -06:00
H. Nikolaus Schaller
ba14fa1a57 regulator: core: silence warning: "VDD1: ramp_delay not set"
commit 73e705bf81 ("regulator: core: Add set_voltage_time op")

introduced a new rdev_warn() if the ramp_delay is 0.

Apparently, on omap3/twl4030 platforms with dynamic voltage
management this results in non-ending spurious messages like

[  511.143066] VDD1: ramp_delay not set
[  511.662322] VDD1: ramp_delay not set
[  513.903625] VDD1: ramp_delay not set
[  514.222198] VDD1: ramp_delay not set
[  517.062835] VDD1: ramp_delay not set
[  517.382568] VDD1: ramp_delay not set
[  520.142791] VDD1: ramp_delay not set
[  520.502593] VDD1: ramp_delay not set
[  523.062896] VDD1: ramp_delay not set
[  523.362701] VDD1: ramp_delay not set
[  526.143035] VDD1: ramp_delay not set

I have observed this on GTA04 while it is reported to occur on
N900 as well: https://bugzilla.kernel.org/show_bug.cgi?id=178371

This patch makes the warning appear only in debugging mode.

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-10-28 18:22:40 +01:00
Mark Brown
2dfcb921da Merge remote-tracking branches 'regulator/topic/of', 'regulator/topic/pv88080', 'regulator/topic/rk808', 'regulator/topic/set-voltage' and 'regulator/topic/tps65218' into regulator-next 2016-09-30 09:13:58 -07:00
Mark Brown
81c383c9ba Merge remote-tracking branches 'regulator/topic/bulk', 'regulator/topic/dbx500', 'regulator/topic/hi6421', 'regulator/topic/load' and 'regulator/topic/ltc3676' into regulator-next 2016-09-30 09:13:55 -07:00
Joonwoo Park
577766175c regulator: core: don't return error with inadequate reason
drms_uA_update() always returns failure when it cannot find regulator's
input voltage.  But if hardware supports load configuration with
ops->set_load() and the input regulator isn't specified with valid reason
such as the input regulator is battery, not finding input voltage is
normal so such case should not return with an error.

Avoid such inadequate error return by checking input/output voltages
only when drms_uA_update() is about to configure load with enum based
ops->set_mode().

Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-09-24 19:36:41 +01:00
Matthias Kaehlcke
73e705bf81 regulator: core: Add set_voltage_time op
The new op is analogous to set_voltage_time_sel. It can be used by
regulators which don't have a table of discrete voltages. The function
returns the time for the regulator output voltage to stabilize after
being set to a new value, in microseconds. If the op is not set a
default implementation is used to calculate the delay.

This change also removes the ramp_delay calculation in the PWM
regulator, since the driver now uses the core code for the calculation
of the delay.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-09-16 18:38:22 +01:00
Matthias Kaehlcke
d89564efe7 regulator: core: Don't skip set_voltage_time when ramp delay disabled
The current code assumes that only the ramp_delay is used to determine
the time needed for the voltage to stabilize. This may be true for the
calculation done by regulator_set_voltage_time_sel(), however regulators
can implement their own set_voltage_time_sel() op which would be skipped
if no ramp delay is specified. Remove the check in
_regulator_do_set_voltage(), the functions calculating the ramp delay
return 0 anyway when the ramp delay is not configured.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-09-16 17:33:40 +01:00
Matthias Kaehlcke
31dfe686ed regulator: core: Simplify error flow in _regulator_do_set_voltage()
If the voltage can not be set jump to the end of the function. This
avoids having to check for an error multiple times and eliminates one
level of nesting in a follow-up change.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-09-16 17:33:40 +01:00
Matthias Kaehlcke
57995a4860 regulator: core: Use local ops variable in _regulator_do_set_voltage()
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-09-14 18:12:20 +01:00
Bjorn Andersson
565f9b073f regulator: Remove support for optional supplies in the bulk API
The patch was based on my missinterpretation of the API and only
accidentally worked for me. Let's clean it out to not confuse others.

This reverts commit 3ff3f518a1.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-08-16 20:00:44 +01:00
Mark Brown
fc1e1c4a24 regulator: Remove regulator_can_change_voltage()
There is little obvious use case for a regualtor driver to know if it is
possible to vary voltages at all by itself.  If a consumer needs to
limit what voltages it tries to set based on the system configuration
then it will need to enumerate the possible voltages, and without that
even if it is possible to change voltages that doesn't mean that
constraints or other consumers will allow whatever change the driver is
trying to do at a given time.  It doesn't even indicate if _set_voltage()
calls will work as noop _set_voltage() calls return success.

There were no users of this API that weren't abusing it and now they're
all gone so remove the API.

Signed-off-by: Mark Brown <broonie@kernel.org>
2016-06-09 11:40:34 +01:00
Mark Brown
78d5501cf4 Merge remote-tracking branches 'regulator/topic/can-change', 'regulator/topic/constrain', 'regulator/topic/debugfs' and 'regulator/topic/doc' into regulator-next 2016-05-13 14:23:27 +01:00
Mark Brown
ab3688541d Merge remote-tracking branch 'regulator/topic/supply' into regulator-next 2016-05-13 14:23:01 +01:00
Mark Brown
170b649e40 Merge remote-tracking branch 'regulator/topic/core' into regulator-next 2016-05-13 14:22:57 +01:00
Mark Brown
75941a1ba3 Merge remote-tracking branch 'regulator/topic/bypass' into regulator-next 2016-05-13 14:22:55 +01:00
Mark Brown
93878cd540 Merge remote-tracking branches 'regulator/fix/constrain' and 'regulator/fix/defer' into regulator-linus 2016-05-13 14:22:43 +01:00
Jon Hunter
45389c4752 regulator: core: Add early supply resolution for regulators
The call to set_machine_constraints() in regulator_register(), will
attempt to get the voltage for the regulator. If a regulator is in
bypass will fail to get the voltage (ie. it's bypass voltage) and
hence register the regulator, because the supply for the regulator has
not been resolved yet.

To fix this, add a call to regulator_resolve_supply() before we call
set_machine_constraints(). If the call to regulator_resolve_supply()
fails, rather than returning an error at this point, allow the
registration of the regulator to continue because for some regulators
resolving the supply at this point may not be necessary and it will be
resolved later as more regulators are added. Furthermore, if the supply
is still not resolved for a bypassed regulator, this will be detected
when we attempt to get the voltage for the regulator and an error will
be propagated at this point.

If a bypassed regulator does not have a supply when we attempt to get
the voltage, rather than returing -EINVAL, return -EPROBE_DEFER instead
to allow the registration of the regulator to be deferred and tried
again later.

Please note that regulator_resolve_supply() will call
regulator_dev_lookup() which may acquire the regulator_list_mutex. To
avoid any deadlocks we cannot hold the regulator_list_mutex when calling
regulator_resolve_supply(). Therefore, rather than holding the lock
around a large portion of the registration code, just hold the lock when
aquiring any GPIOs and setting up supplies because these sections may
add entries to the regulator_map_list and regulator_ena_gpio_list,
respectively.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-04-27 16:32:19 +01:00
Mark Brown
cbc13a66fd Merge branch 'topic/bypass' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator into regulator-supply 2016-04-27 16:32:14 +01:00
WEN Pingbo
8a34e979f6 regulator: refactor valid_ops_mask checking code
To make the code more compat and centralized, this patch add a
unified function - regulator_ops_is_valid. So we can add
some extra checking code easily later.

Signed-off-by: WEN Pingbo <pingbo.wen@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-04-25 18:52:06 +01:00
Jon Hunter
c438b9d017 regulator: core: Move registration of regulator device
The public functions to acquire a regulator, such as regulator_get(),
internally look-up the regulator from the list of regulators that have
been registered with the regulator device class. The registration of
a new regulator with the regulator device class happens before the
regulator has been completely setup. Therefore, it is possible that
the regulator could be acquired before it has been setup successfully.
To avoid this move the device registration of the regulator to the end
of the regulator setup and update the error exit path accordingly.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-04-22 11:38:47 +01:00
Mark Brown
f89ba3383e Merge branch 'topic/sysfs-init' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator into regulator-supply 2016-04-22 11:38:42 +01:00
Jon Hunter
8e5356a736 regulator: core: Clear the supply pointer if enabling fails
During the resolution of a regulator's supply, we may attempt to enable
the supply if the regulator itself is already enabled. If enabling the
supply fails, then we will call _regulator_put() for the supply.
However, the pointer to the supply has not been cleared for the
regulator and this will cause a crash if we then unregister the
regulator and attempt to call regulator_put() a second time for the
supply. Fix this by clearing the supply pointer if enabling the supply
after fails when resolving the supply for a regulator.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-04-22 11:35:54 +01:00
Jon Hunter
7ddede6a58 regulator: core: Don't terminate supply resolution early
The function regulator_register_resolve_supply() is called from the
context of class_for_each_dev() (during the regulator registration) to
resolve any supplies added. regulator_register_resolve_supply() will
return an error if a regulator's supply cannot be resolved and this will
terminate the loop in class_for_each_dev(). This means that we will not
attempt to resolve any other supplies after one has failed. Hence, this
may delay the resolution of other regulator supplies until the failing
one itself can be resolved.

Rather than terminating the loop early, don't return an error code and
keep attempting to resolve any other supplies for regulators that have
been registered.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-04-22 11:34:47 +01:00
Richard Fitzgerald
2d80a91b2f regulator: core: Add debugfs to show constraint flags
There are debugfs entries for voltage and current, but not for
the constraint flags. It's useful for debugging to be able to
see what these flags are so this patch adds a new debugfs file.
We can't use debugfs_create_bool for this because the flags are
bitfields, so as this needs a special read callback they have been
collected into a single file that lists all the flags.

Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-04-22 10:28:52 +01:00
Tero Kristo
07c5c3ad98 regulator: core: remove lockdep assert from suspend_prepare
suspend_prepare can be called during regulator init time also, where
the mutex is not locked yet. This causes a false lockdep warning.
To avoid the problem, remove the lockdep assertion from the function
causing the issue. An alternative would be to lock the mutex during
init, but this would cause other problems (some APIs used during init
will attempt to lock the mutex also, causing deadlock.)

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Reported-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-04-18 18:13:24 +01:00
Mark Brown
2c0a303a12 regulator: core: Fix locking of GPIO list on free
When we acquire a shareable enable GPIO on probe we do so with the
regulator_list_mutex held.  However when we release the GPIOs we do this
immediately after dropping the mutex meaning that the list could become
corrupted.  Move the release into the locked region to avoid this.

Signed-off-by: Mark Brown <broonie@kernel.org>
2016-04-13 07:43:00 +01:00
Boris Brezillon
469b640e4f regulator: reorder initialization steps in regulator_register()
device_register() is calling ->get_voltage() as part of it's sysfs attribute
initialization process, and this functions might need to know the regulator
constraints to return a valid value.
This is at least true for the pwm regulator driver (when operating in
continuous mode) which needs to know the minimum and maximum voltage values
to calculate the current voltage:

min_uV + (((max_uV - min_uV) * dutycycle) / 100);

Move device_register() after set_machine_constraints() to make sure those
constraints are correctly initialized when ->get_voltage() is called.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reported-by: Stephen Barber <smbarber@chromium.org>
Tested-by: Caesar Wang <wxt@rock-chips.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-04-13 07:33:44 +01:00
Mark Brown
fef9501901 regulator: core: Use parent voltage from the supply when bypassed
When a regulator is in bypass mode it is functioning as a switch
returning the voltage set in the regulator will not give the voltage
being output by the regulator as it's just passing through its supply.
This means that when we are getting the voltage from a regulator we
should check to see if it is in bypass mode and if it is we should
report the voltage from the supply rather than that which is set on the
regulator.

Reported-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
[treding@nvidia.com: return early for bypass mode]
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-04-12 05:32:30 +01:00
Jon Hunter
a215137423 regulator: Fix deadlock during regulator registration
Commit 5e3ca2b349 ("regulator: Try to resolve regulators supplies on
registration") added a call to regulator_resolve_supply() within
regulator_register() where the regulator_list_mutex is held. This causes
a deadlock to occur on the Tegra114 Dalmore board when the palmas PMIC
is registered because regulator_register_resolve_supply() calls
regulator_dev_lookup() which may try to acquire the regulator_list_mutex
again.

Fix this by releasing the mutex before calling
regulator_register_resolve_supply() and update the error exit path to
ensure the mutex is released on an error.

[Made commit message more legible -- broonie]

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-03-30 11:03:54 -07:00
Mark Brown
45a91e8f76 regulator: core: Log when we bring constraints into range
This aids in debugging problems triggered by the regulator core applying
its constraints, we could potentially crash immediately after updating
the voltage if the constraints are buggy.

Signed-off-by: Mark Brown <broonie@kernel.org>
2016-03-29 16:37:46 -07:00
Javier Martinez Canillas
5e3ca2b349 regulator: Try to resolve regulators supplies on registration
Commit 6261b06de5 ("regulator: Defer lookup of supply to regulator_get")
moved the regulator supplies lookup logic from the regulators registration
to the regulators get time.

Unfortunately, that changed the behavior of the regulator core since now a
parent supply with a child regulator marked as always-on, won't be enabled
unless a client driver attempts to get the child regulator during boot.

This patch tries to resolve the parent supply for the already registered
regulators each time that a new regulator is registered. So the regulators
that have child regulators marked as always on will be enabled regardless
if a driver gets the child regulator or not.

That was the behavior before the mentioned commit, since parent supplies
were looked up at regulator registration time instead of during child get.

Since regulator_resolve_supply() checks for rdev->supply, most of the times
it will be a no-op. Errors aren't checked to keep the possible out of order
dependencies which was the motivation for the mentioned commit.

Also, the supply being available will be enforced on regulator get anyways
in case the resolve fails on regulators registration.

Fixes: 6261b06de5 ("regulator: Defer lookup of supply to regulator_get")
Suggested-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: <stable@vger.kernel.org> # 4.1+
2016-03-28 10:42:45 +01:00
Mark Brown
fa93fd4ecc regulator: core: Ensure we are at least in bounds for our constraints
Currently we only attempt to set the voltage during constraints
application if an exact voltage is specified.  Extend this so that if
the currently set voltage for the regulator is outside the bounds set in
constraints we will move the voltage to the nearest constraint, raising
to the minimum or lowering to the maximum as needed.  This ensures that
drivers can probe without the hardware being driven out of spec.

Reported-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Tested-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-03-27 10:02:43 +01:00
Vladimir Zapolskiy
e437b90026 regulator: core: Remove duplicate copy of active-discharge parsing
Apparently due to a wrongly resolved merge conflict between two
branches, which contained the same commit, the commit contents
partially was added two times in a row.

This change reverts the latter wrong inclusion of commit 909f7ee0b5
("regulator: core: Add support for active-discharge configuration").

The first applied commit 670666b9e0 ("regulator: core: Add support
for active-discharge configuration") is not touched.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-03-25 11:12:33 +00:00
Javier Martinez Canillas
95a293c7ba regulator: Remove unneded check for regulator supply
The regulator_resolve_supply() function checks if a supply has been
associated with a regulator to avoid enabling it if that is not the
case.

But the supply was already looked up with regulator_resolve_supply()
and set with set_supply() before the check and both return on error.

So the fact that this statement has been reached means that neither
of them failed and a supply must be associated with the regulator.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-03-21 13:35:30 +00:00
Mark Brown
d6d50a8f17 Merge remote-tracking branches 'regulator/topic/ltc3589', 'regulator/topic/max77620', 'regulator/topic/max77686', 'regulator/topic/max77802' and 'regulator/topic/maxim' into regulator-next 2016-03-13 15:19:47 +07:00
Mark Brown
d1f83021d5 Merge remote-tracking branches 'regulator/topic/discharge', 'regulator/topic/fan53555', 'regulator/topic/gpio', 'regulator/topic/hi655x' and 'regulator/topic/lp872x' into regulator-next 2016-03-13 15:19:35 +07:00
Laxman Dewangan
909f7ee0b5 regulator: core: Add support for active-discharge configuration
Add support to enable/disable active discharge of regulator via
machine constraints. This configuration is done when setting
machine constraint during regulator register and if regulator
driver implemented the callback ops.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-03-02 23:31:45 +09:00
Laxman Dewangan
670666b9e0 regulator: core: Add support for active-discharge configuration
Add support to enable/disable active discharge of regulator via
machine constraints. This configuration is done when setting
machine constraint during regulator register and if regulator
driver implemented the callback ops.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-03-02 23:13:05 +09:00
Krzysztof Adamski
32165230eb regulator: core: fix crash in error path of regulator_register
This problem was introduced by:
commit daad134d66 ("regulator: core: Request GPIO before creating
sysfs entries")

The error path was not updated correctly after moving GPIO registration
code and in case regulator_ena_gpio_free failed, device_unregister() was
called even though device_register() was not yet called.

This problem breaks the boot at least on all Tegra 32-bit devices. It
will also crash each device that specifices GPIO that is unavaiable at
regulator_register call. Here's error log I've got when forced GPIO to
be invalid:

[    1.116612] usb-otg-vbus-reg: Failed to request enable GPIO10: -22
[    1.122794] Unable to handle kernel NULL pointer dereference at
virtual address 00000044
[    1.130894] pgd = c0004000
[    1.133598] [00000044] *pgd=00000000
[    1.137205] Internal error: Oops: 5 [#1] SMP ARM

and here's backtrace from KDB:

Exception stack(0xef11fbd0 to 0xef11fc18)
fbc0:                                     00000000 c0738a14 00000000 00000000
fbe0: c0b2a0b0 00000000 00000000 c0738a14 c0b5fdf8 00000001 ef7f6074 ef11fc4c
fc00: ef11fc50 ef11fc20 c02a8344 c02a7f1c 60000013 ffffffff
[<c010cee0>] (__dabt_svc) from [<c02a7f1c>] (kernfs_find_ns+0x18/0xf8)
[<c02a7f1c>] (kernfs_find_ns) from [<c02a8344>] (kernfs_find_and_get_ns+0x40/0x58)
[<c02a8344>] (kernfs_find_and_get_ns) from [<c02ac4a4>] (sysfs_unmerge_group+0x28/0x68)
[<c02ac4a4>] (sysfs_unmerge_group) from [<c044389c>] (dpm_sysfs_remove+0x30/0x5c)
[<c044389c>] (dpm_sysfs_remove) from [<c0436ba8>] (device_del+0x48/0x1f4)
[<c0436ba8>] (device_del) from [<c0436d84>] (device_unregister+0x30/0x6c)
[<c0436d84>] (device_unregister) from [<c0403910>] (regulator_register+0x6d0/0xdac)
[<c0403910>] (regulator_register) from [<c04052d4>] (devm_regulator_register+0x50/0x84)
[<c04052d4>] (devm_regulator_register) from [<c0406298>] (reg_fixed_voltage_probe+0x25c/0x3c0)
[<c0406298>] (reg_fixed_voltage_probe) from [<c043d21c>] (platform_drv_probe+0x60/0xb0)
[<c043d21c>] (platform_drv_probe) from [<c043b078>] (driver_probe_device+0x24c/0x440)
[<c043b078>] (driver_probe_device) from [<c043b5e8>] (__device_attach_driver+0xc0/0x120)
[<c043b5e8>] (__device_attach_driver) from [<c043901c>] (bus_for_each_drv+0x6c/0x98)
[<c043901c>] (bus_for_each_drv) from [<c043ad20>] (__device_attach+0xac/0x138)
[<c043ad20>] (__device_attach) from [<c043b664>] (device_initial_probe+0x1c/0x20)
[<c043b664>] (device_initial_probe) from [<c043a074>] (bus_probe_device+0x94/0x9c)
[<c043a074>] (bus_probe_device) from [<c043a610>] (deferred_probe_work_func+0x80/0xcc)
[<c043a610>] (deferred_probe_work_func) from [<c01381d0>] (process_one_work+0x158/0x454)
[<c01381d0>] (process_one_work) from [<c013854c>] (worker_thread+0x38/0x510)
[<c013854c>] (worker_thread) from [<c013e154>] (kthread+0xe8/0x104)
[<c013e154>] (kthread) from [<c0108638>] (ret_from_fork+0x14/0x3c)

Signed-off-by: Krzysztof Adamski <krzysztof.adamski@tieto.com>
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-25 10:48:16 +09:00
Mark Brown
ece497ae37 Merge branch 'fix/core' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator into regulator-core 2016-02-25 10:48:11 +09:00
Krzysztof Adamski
daad134d66 regulator: core: Request GPIO before creating sysfs entries
regulator_attr_is_visible (which is a .is_visible callback of
regulator_dev_group attribute_grpup) checks rdev->ena_pin to decide if
"status" file should be present in sysfs. This field is set at the end
of regulator_ena_gpio_request so it has to be called before
device_register() otherwise this test will always fail, causing "status"
file to not be visible.

Since regulator_attr_is_visible also tests for is_enabled() op, this
problem is only visible for regulators that does not define this
callback, like regulator-fixed.c.

Signed-off-by: Krzysztof Adamski <krzysztof.adamski@tieto.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-22 19:51:05 +09:00
Charles Keepax
6333ef46bb regulator: core: Rely on regulator_dev_release to free constraints
As we now free the constraints in regulator_dev_release we will still
call free on the constraints pointer even if we went down an error
path in regulator_register, because it is only allocated after the
device_register. As such we no longer need to free rdev->constraints
on the error paths, so this patch removes said frees.

Fixes: 29f5f4860a ("regulator: core: Move more deallocation into class unregister")
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-01-27 14:41:42 +00:00
Mark Brown
3fbd90bf6b Merge remote-tracking branches 'regulator/topic/lp8788', 'regulator/topic/mt6311', 'regulator/topic/optional', 'regulator/topic/palmas' and 'regulator/topic/pv88060' into regulator-next 2016-01-12 18:26:07 +00:00
Mark Brown
8bd31df8de Merge remote-tracking branches 'regulator/topic/const', 'regulator/topic/lm363x', 'regulator/topic/lockdep' and 'regulator/topic/lp872x' into regulator-next 2016-01-12 18:26:05 +00:00
Mark Brown
9fa295742d Merge remote-tracking branch 'regulator/topic/core' into regulator-next 2016-01-12 18:26:05 +00:00
Dan Carpenter
70dc6daff0 regulator: core: remove some dead code
Originally queue_delayed_work() used to negative error codes or 0 and 1
on success depending if the work was queued or not.  It caused a lot of
bugs where people treated all non-zero returns as failures so we changed
it to return bool instead in d4283e9378 ('workqueue: make queueing
functions return bool').  Now it never returns failure.

Checking for negative values causes a static checker warning since it is
impossible based on the bool type.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-01-07 15:41:02 +00:00
Geliang Tang
83080a1408 regulator: core: use dev_to_rdev
Use dev_to_rdev() instead of open-coding it.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-01-05 14:20:50 +00:00
Thierry Reding
70a7fb80e8 regulator: core: Fix nested locking of supplies
Commit fa731ac7ea ("regulator: core: avoid unused variable warning")
introduced a subtle change in how supplies are locked. Where previously
code was always locking the regulator of the current iteration, the new
implementation only locks the regulator if it has a supply. For any
given power tree that means that the root will never get locked.

On the other hand the regulator_unlock_supply() will still release all
the locks, which in turn causes the lock debugging code to warn about a
mutex being unlocked which wasn't locked.

Cc: Mark Brown <broonie@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Fixes: Fixes: fa731ac7ea ("regulator: core: avoid unused variable warning")
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-12-02 17:22:10 +00:00
Mark Brown
49a6bb7a1c regulator: core: Ensure we lock all regulators
The latest workaround for the lockdep interface's not using the second
argument of mutex_lock_nested() changed the loop missed locking the last
regulator due to a thinko with the loop termination condition exiting
one regulator too soon.

Reported-by: Tyler Baker <tyler.baker@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-12-02 17:20:33 +00:00
Arnd Bergmann
bb41897e38 regulator: core: fix regulator_lock_supply regression
As noticed by Geert Uytterhoeven, my patch to avoid a harmless build warning
in regulator_lock_supply() was total crap and introduced a real bug:

> [ BUG: bad unlock balance detected! ]
> kworker/u4:0/6 is trying to release lock (&rdev->mutex) at:
> [<c0247b84>] regulator_set_voltage+0x38/0x50

we still lock the regulator supplies, but not the actual regulators,
so we are missing a lock, and the unlock is unbalanced.

This rectifies it by first locking the regulator device itself before
using the same loop as before to lock its supplies.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 716fec9d1965 ("[SUBMITTED] regulator: core: avoid unused variable warning")
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-11-27 16:37:04 +00:00
Arnd Bergmann
fa731ac7ea regulator: core: avoid unused variable warning
The second argument of the mutex_lock_nested() helper is only
evaluated if CONFIG_DEBUG_LOCK_ALLOC is set. Otherwise we
get this build warning for the new regulator_lock_supply
function:

drivers/regulator/core.c: In function 'regulator_lock_supply':
drivers/regulator/core.c:142:6: warning: unused variable 'i' [-Wunused-variable]

To avoid the warning, this restructures the code to make it
both simpler and to move the 'i++' outside of the mutex_lock_nested
call, where it is now always used and the variable is not
flagged as unused.

We had some discussion about changing mutex_lock_nested to an
inline function, which would make the code do the right thing here,
but in the end decided against it, in order to guarantee that
mutex_lock_nested() does not introduced overhead without
CONFIG_DEBUG_LOCK_ALLOC.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 9f01cd4a91 ("regulator: core: introduce function to lock regulators and its supplies")
Link: http://permalink.gmane.org/gmane.linux.kernel/2068900
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-11-20 18:04:34 +00:00
Bjorn Andersson
3ff3f518a1 regulator: Make bulk API support optional supplies
Make it possible to use the bulk API with optional supplies, by allowing
the consumer to marking supplies as optional in the regulator_bulk_data.

Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-11-17 18:54:07 +00:00
Mark Brown
62e544b983 Merge remote-tracking branches 'regulator/topic/supply', 'regulator/topic/tps6105x' and 'regulator/topic/tps65023' into regulator-next 2015-11-04 11:19:43 +00:00
Mark Brown
5408dd8f09 Merge remote-tracking branch 'regulator/topic/list' into regulator-next 2015-11-04 11:19:36 +00:00
Mark Brown
ce3c059731 Merge remote-tracking branch 'regulator/topic/core' into regulator-next 2015-11-04 11:19:36 +00:00
Mark Brown
d9b96d35d2 regulator: Use regulator_lock_supply() for get_voltage() too
Since we need to read voltages of parents as part of setting supply
voltages we need to be able to do get_voltage() internally without
taking locks so reorganize the locking to take locks on the full tree on
entry rather than as we recurse when called externally.

Reported-by: John Stultz <john.stultz@linaro.org>
Tested-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-11-04 10:16:05 +00:00
Sascha Hauer
fc42112c0e regulator: core: Propagate voltage changes to supply regulators
Until now changing the voltage of a regulator only ever effected the
regulator itself, but never its supplies. It's a common pattern though
to put LDO regulators behind switching regulators. The switching
regulators efficiently drop the input voltage but have a high ripple on
their output. The output is then cleaned up by the LDOs. For higher
energy efficiency the voltage drop at the LDOs should be minimized. For
this scenario we need to propagate the voltage change to the supply
regulators. Another scenario where voltage propagation is desired is
a regulator which only consists of a switch and thus cannot regulate
voltages itself. In this case we can pass setting voltages to the
supply.

This patch adds support for voltage propagation. We do voltage
propagation when the current regulator has a minimum dropout voltage
specified or if the current regulator lacks a get_voltage operation
(indicating it's a switch and not a regulator).

Changing the supply voltage must be done carefully. When we are
increasing the current regulators output we must first increase the
supply voltage and then the regulator itself. When we are decreasing the
current regulators voltage we must decrease the supply voltage after
changing the current regulators voltage.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-22 13:34:11 +01:00
Sascha Hauer
a204f41e2d regulator: core: Factor out regulator_map_voltage
_regulator_call_set_voltage has code to translate a minimum/maximum
voltage pair into a selector. This code is useful for others aswell,
so create a regulator_map_voltage function.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-20 15:43:53 +01:00
Sascha Hauer
a9f226bcd9 regulator: core: create unlocked version of regulator_set_voltage
The unlocked version will be needed when we start propagating voltage
changes to the supply regulators.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-16 17:55:55 +01:00
Sascha Hauer
3a40cfc36b regulator: core: create unlocked version of regulator_list_voltage
The unlocked version will be needed when we start propagating voltage
changes to the supply regulators.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-01 12:28:42 +01:00
Sascha Hauer
9f01cd4a91 regulator: core: introduce function to lock regulators and its supplies
Each regulator_dev is locked with its own mutex. This is fine as long
as only one regulator_dev is locked, but makes lockdep unhappy when we
have to walk up the supply chain like it can happen in
regulator_get_voltage:

regulator_get_voltage ->
 mutex_lock(&regulator->rdev->mutex) ->
_regulator_get_voltage(regulator->rdev) ->
regulator_get_voltage(rdev->supply) ->
mutex_lock(&regulator->rdev->mutex);

This causes lockdep to issue a possible deadlock warning.

There are at least two ways to work around this:

- We can always lock the whole supply chain using the functions
  introduced with this patch.
- We could store the current voltage in struct regulator_rdev so
  that we do not have to walk up the supply chain for the
  _regulator_get_voltage case.

Anyway, regulator_lock_supply/regulator_unlock_supply will be needed
once we allow regulator_set_voltage to optimize the supply voltages.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-01 12:28:42 +01:00
Mark Brown
06423121d9 regulator: core: Handle probe deferral from DT when resolving supplies
When resolving regulator-regulator supplies we ignore probe deferral
returns from regulator_dev_lookup() (such as are generated for DT when
we can see a supply is registered) and just fall back to the dummy
regulator if there are full constraints (as is the case for DT).  This
means that probe deferral is broken for DT systems, fix that by paying
attention to -EPROBE_DEFER return codes like we do -ENODEV.

A further patch will simplify this further, this is a minimal fix for
the specific issue.

Fixes: 9f7e25edb1 (regulator: core: Handle full constraints systems when resolving supplies)
Reported-by: Sascha Hauer <s.hauer@pengutronix.de>
Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonnie@kernel.org>
Cc: stable@vger.kernel.org
2015-10-01 11:10:29 +01:00