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>
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>
_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>
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>
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>
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(®ulator->rdev->mutex) ->
_regulator_get_voltage(regulator->rdev) ->
regulator_get_voltage(rdev->supply) ->
mutex_lock(®ulator->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>
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
As we are already registering a device with regulator_class for each
regulator device, regulator_list is redundant and can be replaced with
calls to class_find_device() and class_for_each_device().
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The ret pointer passed to regulator_dev_lookup is only filled with a
valid error code if regulator_dev_lookup returned NULL. Currently
regulator_resolve_supply checks this ret value before it checks if a
regulator was returned, this can result in valid regulator lookups being
ignored.
Fixes: 6261b06de5 ("regulator: Defer lookup of supply to regulator_get")
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
The same error print exists 4 times in the regulator core
<rdev>: operation not allowed
Unfortunately, seeing this in the dmesg is not very informative.
Add what type of operation is not allowed to the message so that
these errors are unique, hopefully pointing developers in the
right direction
<rdev>: drms operation not allowed
<rdev>: voltage operation not allowed
<rdev>: current operation not allowed
<rdev>: mode operation not allowed
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
This has been a busy release for regmap. By far the biggest set of
changes here are those from Markus Pargmann which implement support for
block transfers in smbus devices. This required quite a bit of
refactoring but leaves us better able to handle odd restrictions that
controllers may have and with better performance on smbus.
Other new features include:
- Fix interactions with lockdep for nested regmaps (eg, when a device
using regmap is connected to a bus where the bus controller has a
separate regmap). Lockdep's default class identification is too
crude to work without help.
- Support for must write bitfield operations, useful for operations
which require writing a bit to trigger them from Kuniori Morimoto.
- Support for delaying during register patch application from Nariman
Poushin.
- Support for overriding cache state via the debugfs implementation
from Richard Fitzgerald.
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Merge tag 'regmap-v4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap
Pull regmap updates from Mark Brown:
"This has been a busy release for regmap.
By far the biggest set of changes here are those from Markus Pargmann
which implement support for block transfers in smbus devices. This
required quite a bit of refactoring but leaves us better able to
handle odd restrictions that controllers may have and with better
performance on smbus.
Other new features include:
- Fix interactions with lockdep for nested regmaps (eg, when a device
using regmap is connected to a bus where the bus controller has a
separate regmap). Lockdep's default class identification is too
crude to work without help.
- Support for must write bitfield operations, useful for operations
which require writing a bit to trigger them from Kuniori Morimoto.
- Support for delaying during register patch application from Nariman
Poushin.
- Support for overriding cache state via the debugfs implementation
from Richard Fitzgerald"
* tag 'regmap-v4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: (25 commits)
regmap: fix a NULL pointer dereference in __regmap_init
regmap: Support bulk reads for devices without raw formatting
regmap-i2c: Add smbus i2c block support
regmap: Add raw_write/read checks for max_raw_write/read sizes
regmap: regmap max_raw_read/write getter functions
regmap: Introduce max_raw_read/write for regmap_bulk_read/write
regmap: Add missing comments about struct regmap_bus
regmap: No multi_write support if bus->write does not exist
regmap: Split use_single_rw internally into use_single_read/write
regmap: Fix regmap_bulk_write for bus writes
regmap: regmap_raw_read return error on !bus->read
regulator: core: Print at debug level on debugfs creation failure
regmap: Fix regmap_can_raw_write check
regmap: fix typos in regmap.c
regmap: Fix integertypes for register address and value
regmap: Move documentation to regmap.h
regmap: Use different lockdep class for each regmap init call
thermal: sti: Add parentheses around bridge->ops->regmap_init call
mfd: vexpress: Add parentheses around bridge->ops->regmap_init call
regmap: debugfs: Fix misuse of IS_ENABLED
...
We were checking rdev->supply for NULL after dereferencing it. Lets
check for rdev->supply along with _regulator_is_enabled() and call
regulator_enable() only if rdev->supply is not NULL.
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
When calling regulator_set_load, regulator_check_drms prints and returns
an error if the regulator device's flag REGULATOR_CHANGE_DRMS isn't set.
drms_uA_update, however, bails out without reporting an error.
Replace the error print with a debug level print so that we don't get
such prints when the underlying regulator doesn't support DRMS.
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Failure to create a debugfs node is not an error, but we print a
warning upon failure to create the node. Downgrade this to a
debug printk so that we're quiet here. This allows multiple
drivers to request a CPU's regulator so that CPUfreq and AVSish
drivers can coexist.
The downside of this approach is that whoever gets to debugfs first
the others who come later to not have any debugfs attributes associated
with them.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The regulator_list has exactly the same contents as the list that the
driver core maintains of regulator_class members so is redundant. As a
first step in converting over to use the class device list convert our
iteration in late_initcall() to use the class device iterator.
Signed-off-by: Mark Brown <broonie@kernel.org>
We really ought to be using the class dvice lifetime management features
more than we are rather than open coding them so take a step towards that
by moving some of the simplest deallocations to the dev_release() function.
Signed-off-by: Mark Brown <broonie@kernel.org>
When we release a regulator we need to remove references to it from the
rdev which means locking the rdev. Currently we also free resources
associated with the regulator inside the rdev lock but there is no need
to do this, we can reduce the region the lock is held by restricting it
to just actions that affect the rdev.
Signed-off-by: Mark Brown <broonie@kernel.org>
When removing a regulator we hold regulator_list_mutex in order to
ensure the regualtor doesn't become removed again. However we only need
to protect the list until we remove the regulator from the list so move
the unlock earlier to reduce the locked region.
Signed-off-by: Mark Brown <broonie@kernel.org>
Some regulators can automatically shut down when they detect an
over current event. Add an op (set_over_current_protection) and a
DT property + constraint to support this capability.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The regulator_resolve_supply() function calls set_supply() which in turn
calls create_regulator() to allocate a supply regulator.
If an error occurs after set_supply() succeeded, the allocated regulator
has to be freed before propagating the error code.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
When a regulator is unregistered with regulator_unregister(), a call to
regulator_put() is made for its input supply if there is one. This does
a module_put() to decrement the refcount of the module that owns the
supply but there isn't a corresponding try_module_get() in set_supply()
to make the calls balanced.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
When resolving device supplies if we fail to look up the regulator we
substitute in the dummy supply instead if the system has fully specified
constraints. When resolving supplies for regulators we do not have the
equivalent code and instead just directly use the regulator_dev_lookup()
result causing spurious failures.
This does not affect DT systems since we are able to detect missing
mappings directly as part of regulator_dev_lookup() and so have appropriate
handling in the DT specific code.
Reported-by: Christian Hartmann <cornogle@googlemail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add lockdep_assert_held_once() to functions explicitly mentioning that
rdev or regulator_list mutex must be held. Using WARN_ONCE shouldn't
pollute the dmesg to much.
The patch (if CONFIG_LOCKDEP enabled) will show warnings in certain
regulators calling regulator_notifier_call_chain() without rdev->mutex
held.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some regulators can limit their input current (typically annotated
as ilim). Add an op (set_input_current_limit) and a DT property +
constraint to support this.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some regulators support a "soft start" feature where the voltage
ramps up slowly when the regulator is enabled. Add an op
(set_soft_start) and a DT property + constraint to support this.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some regulators need to be configured to pull down a resistor
when the regulator is disabled. Add an op (set_pull_down) and a
DT property + constraint to support this.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some regulators have a fixed load that isn't captured by
consumers that the kernel knows about. Add a constraint to
support this.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
In order to avoid potential overflows in print_constraints we
better replace sprintf() with scnprintf().
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
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 <stefan.wahren@i2se.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: <stable@vger.kernel.org>
We weren't taking into account the already used buffer when telling
sprintf() where to print to.
Reported-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
We don't consider a failure to add the sysfs node as a problem,
so use sysfs_create_link_nowarn() so that we don't print a
backtrace when duplicated files exist. Also, downgrade the printk
message to a debug statement so that we're quiet here. This
allows multiple drivers to request a CPU's regulator so that
CPUfreq and AVSish drivers can coexist.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Voltage regulators can have (unregulated) current limits too, so we should
probably output both voltage and current for all regulators.
Holding the rdev->mutex actually conflicts with _regulator_get_current_limit
but also is not really necessary, as the global regulator_list_mutex already
protects us from the regulator vanishing while we go through the list.
On the rk3288-firefly the summary now looks like:
regulator use open bypass voltage current min max
-------------------------------------------------------------------------------
vcc_sys 0 12 0 5000mV 0mA 5000mV 5000mV
vcc_lan 1 1 0 3300mV 0mA 3300mV 3300mV
ff290000.ethernet 0mV 0mV
vcca_33 0 0 0 3300mV 0mA 3300mV 3300mV
vcca_18 0 0 0 1800mV 0mA 1800mV 1800mV
vdd10_lcd 0 0 0 1000mV 0mA 1000mV 1000mV
[...]
Suggested-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
On modern systems the regulator hierarchy can get quite long and nested
with regulators supplying other regulators. In some cases when debugging
it might be nice to get a tree of these regulators, their consumers
and the regulation constraints in one go.
To achieve this add a regulator_summary sysfs node, similar to
clk_summary in the common clock framework, that walks the regulator
list and creates a tree out of the regulators, their consumers and
core per-regulator settings.
On a rk3288-firefly the regulator_summary would for example look
something like:
regulator use open bypass value min max
-----------------------------------------------------------------------
vcc_sys 0 12 0 5000mV 5000mV 5000mV
vcc_lan 1 1 0 3300mV 3300mV 3300mV
ff290000.ethernet 0mV 0mV
vcca_33 0 0 0 3300mV 3300mV 3300mV
vcca_18 0 0 0 1800mV 1800mV 1800mV
vdd10_lcd 0 0 0 1000mV 1000mV 1000mV
vccio_sd 0 0 0 3300mV 3300mV 3300mV
vcc_20 0 3 0 2000mV 2000mV 2000mV
vcc18_lcd 0 0 0 1800mV 1800mV 1800mV
vcc_18 0 2 0 1800mV 1800mV 1800mV
ff100000.saradc 0mV 0mV
ff0d0000.dwmmc 1650mV 1950mV
vdd_10 0 0 0 1000mV 1000mV 1000mV
vdd_log 0 0 0 1100mV 1100mV 1100mV
vcc_io 0 3 0 3300mV 3300mV 3300mV
ff0f0000.dwmmc 3300mV 3400mV
vcc_flash 1 1 0 1800mV 1800mV 1800mV
ff0f0000.dwmmc 1700mV 1950mV
vcc_sd 1 1 0 3300mV 3300mV 3300mV
ff0c0000.dwmmc 3300mV 3400mV
vcc_ddr 0 0 0 1200mV 1200mV 1200mV
vdd_gpu 0 0 0 1000mV 850mV 1350mV
vdd_cpu 0 1 0 900mV 850mV 1350mV
cpu0 900mV 900mV
vcc_5v 0 2 0 5000mV 5000mV 5000mV
vcc_otg_5v 0 0 0 5000mV 5000mV 5000mV
vcc_host_5v 0 0 0 5000mV 5000mV 5000mV
regulator-dummy 0 0 0 0mV 0mV 0mV
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
