General support for state persistence is added to gpiolib with the
introduction of a new pinconf parameter to propagate the request to
hardware. The existing persistence support for sleep is adapted to
include hardware support if the GPIO driver provides it. Persistence
continues to be enabled by default; in-kernel consumers can opt out, but
userspace (currently) does not have a choice.
The *_SLEEP_MAY_LOSE_VALUE and *_SLEEP_MAINTAIN_VALUE symbols are
renamed, dropping the SLEEP prefix to reflect that the concept is no
longer sleep-specific. I feel that renaming to just *_MAY_LOSE_VALUE
could initially be misinterpreted, so I've further changed the symbols
to *_TRANSITORY and *_PERSISTENT to address this.
The sysfs interface is modified only to keep consistency with the
chardev interface in enforcing persistence for userspace exports.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Some pin controllers (such as the Gemini) can control the
expected clock skew and output delay on certain pins with a
sub-nanosecond granularity. This is typically done by shunting
in a number of double inverters in front of or behind the pin.
Make it possible to configure this with a generic binding.
Cc: devicetree@vger.kernel.org
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
In some scenarios, we should set some pins as input/output/pullup/pulldown
when the specified system goes into deep sleep mode, then when the system
goes into deep sleep mode, these pins will be set automatically by hardware.
That means some pins are not controlled by any specific driver in the OS, but
need to be controlled when entering sleep mode. Thus we introduce one sleep
state config into pinconf-generic for users to configure.
Signed-off-by: Baolin Wang <baolin.wang@spreadtrum.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Update deprecated references to Documentation/pinctrl.txt since it has been
moved to Documentation/driver-api/pinctl.rst.
Signed-off-by: Ludovic Desroches <ludovic.desroches@o2linux.fr>
Fixes: 5a9b73832e ("pinctrl.txt: move it to the driver-api book")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add output-enable generic pin configuration property.
This properties allows enabling/disabling pin's output capabilities
without actually driving any value on the line.
Acked-by: Rob Herring <robh@kernel.org>
[Added inline elaborations on buffer enabling/disabling]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This reverts commit 8c58f1a7a4.
It turns out that applying these generic properties was
premature: the properties used in the driver using this
are of unclear electrical nature and the subject need to
be discussed.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add bi-directional and output-enable pin configuration properties.
bi-directional allows to specify when a pin shall operate in input and
output mode at the same time. This is particularly useful in platforms
where input and output buffers have to be manually enabled.
output-enable is just syntactic sugar to specify that a pin shall
operate in output mode, ignoring the provided argument.
This pairs with input-enable pin configuration option.
Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Currently we already have two pin configuration related callbacks
available for GPIO chips .set_single_ended() and .set_debounce(). In
future we expect to have even more, which does not scale well if we need
to add yet another callback to the GPIO chip structure for each possible
configuration parameter.
Better solution is to reuse what we already have available in the
generic pinconf.
To support this, we introduce a new .set_config() callback for GPIO
chips. The callback takes a single packed pin configuration value as
parameter. This can then be extended easily beyond what is currently
supported by just adding new types to the generic pinconf enum.
If the GPIO driver is backed up by a pinctrl driver the GPIO driver can
just assign gpiochip_generic_config() (introduced in this patch) to
.set_config and that will take care configuration requests are directed
to the pinctrl driver.
We then convert the existing drivers over .set_config() and finally
remove the .set_single_ended() and .set_debounce() callbacks.
Suggested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The current pinconf packed format allows only 16-bit argument limiting
the maximum value 65535. For most types this is enough. However,
debounce time can be in range of hundreths of milliseconds in case of
mechanical switches so we cannot represent the worst case using the
current format.
In order to support larger values change the packed format so that the
lower 8 bits are used as type which leaves 24 bits for the argument.
This allows representing values up to 16777215 and debounce times up to
16 seconds.
We also convert the existing users to use 32-bit integer when extracting
argument from the packed configuration value.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The pinconf-generic.h file exposes functions for creating generic mappings
but it does not expose a function for freeing the mappings. Add a function
for freeing generic mappings.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Currently, the dt_params array in drivers/pinctrl/pinconf-generic.c
is not sorted in the same order as the enum pin_config_param in
include/linux/pinctrl/pinconf-generic.h.
Sort enum pin_config_param, conf_items, dt_params, alphabetically
for consistency.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
New pin controllers such as ACPI-based may also have custom properties
to parse, and should be able to use generic pin config. Let's make the
code compile on !OF systems and rename members a bit to underscore it
is custom parameters and not necessarily DT parameters.
This fixes a build regression for x86_64 on the zeroday kernel builds.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reviewed-and-tested-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Additionally to the generic DT parameters, allow drivers to provide
driver-specific DT parameters to be used with the generic parser
infrastructure.
To achieve this 'struct pinctrl_desc' is extended to pass custom pinconf
option to the core. In order to pass this kind of information, the
related data structures - 'struct pinconf_generic_dt_params',
'pin_config_item' - are moved from pinconf internals to the
pinconf-generic header.
Additionally pinconfg-generic is refactored to not only iterate over the
generic pinconf parameters but also take the parameters into account
that are provided through the driver's 'struct pinctrl_desc'.
In particular 'pinconf_generic_parse_dt_config()' and
'pinconf_generic_dump' helpers are split into two parts each. In order
to have a more generic helper that can be used to process the generic
parameters as well as the driver-specific ones.
v2:
- fix typo
- add missing documentation for @conf_items member in struct
- rebase to pinctrl/devel: conflict in abx500
- rename _pinconf_generic_dump() to pinconf_generic_dump_one()
- removed '_' from _parse_dt_cfg()
- removed BUG_ONs, error condition is handled in if statements
- removed pinconf_generic_dump_group() & pinconf_generic_dump_pin
helpers
- fixed up corresponding call sites
- renamed pinconf_generic_dump() to pinconf_generic_dump_pins()
- added kernel-doc to pinconf_generic_dump_pins()
- add kernel-doc
- more verbose commit message
Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
With the new 'groups' property, the DT parser can infer the map type
from the fact whether 'pins' or 'groups' is used to specify the pin
group to work on.
To maintain backwards compatibitliy with current usage of the DT
binding, this is only done when PIN_MAP_TYPE_INVALID is passed to the
parsing function as type.
Also, a new helper 'pinconf_generic_dt_node_to_map_all()' is introduced,
which can be used by drivers as generic callback for dt_node_to_map() to
leverage the new feature.
Changes since v2:
- rename dt_pin_specifier to subnode_target_type
- add additional comment in header file explaining passing an invalid
map type
- mention map_all() helper in commit message
Changes since RFC v2:
- none
Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
PIN_CONFIG_DRIVE_OPEN_SOURCE enables open source, not open drain.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit adds slew-rate and input-enable/disable support for pinconf
-generic.
Signed-off-by: Sherman Yin <syin@broadcom.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The PIN_CONFIG_OUTPUT parameter is really tricky to understand
and needs an explicit pointer to the documentation.
Cc: Tomasz Figa <t.figa@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add support to pass the config type like GROUP or PIN when using
the utils or generic pin configuration APIs. This will make the
APIs more generic.
Added additional inline APIs such that it can be use directly as
callback for the pinctrl_ops.
Changes from V1:
- Remove separate implementation for pins and group for
pinctrl_utils_dt_free_map and improve this function
to support both i.e. PINS and GROUPs.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Commit e81c8f18af
"pinctrl: pinconf-generic: add generic APIs for mapping pinctrl node"
Added function prototypes with implicit dependencies
on other header files causing build warnings like this:
In file included from
arch/arm/mach-ux500/board-mop500-pins.c:12:0:
include/linux/pinctrl/pinconf-generic.h:142:3:
warning: 'struct device_node' declared inside parameter list [enabled
by default]
unsigned *reserved_maps, unsigned *num_maps);
^
include/linux/pinctrl/pinconf-generic.h:142:3:
warning: its scope is only this definition or declaration, which is
probably not what you want [enabled by default]
include/linux/pinctrl/pinconf-generic.h:142:3:
warning: 'struct pinctrl_dev' declared inside parameter list [enabled
by default]
include/linux/pinctrl/pinconf-generic.h:145:3:
warning: 'struct device_node' declared inside parameter list [enabled
by default]
unsigned *num_maps);
^
Let's just add ifdefs for non-DT systems (the actual code is
already ifdefed) and #include <linux/device.h> to get the
most important structs and forward-declare the pinctrl
core structs.
Reported-by: Olof Johansson <olof@lixom.net>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add generic APIs to map the DT node and its sub node in pinconf generic
driver. These APIs can be used from driver to parse the DT node who
uses the pinconf generic APIs for defining their nodes.
Changes from V1:
- Add generic property for pins and functions in pinconf-generic.
- Add APIs to map the DT and subnode.
- Move common utils APIs to the pinctrl-utils from this file.
- Update the binding document accordingly.
Changes from V2:
- Rebased the pinctrl binding doc on top of Stephen's cleanup.
- Rename properties "pinctrl-pins" and "pinctrl-function" to
"pins" and "function".
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Currently the debounce time pinconfig option uses an unspecified
"time units" unit. As pinconfig options should use SI units and a
real unit is also necessary for generic dt bindings, change it
to usec. Currently no driver is using the generic pinconfig option
for this, so the unit change is safe to do.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
PULL_PIN_DEFAULT is meant for hardware completely hiding any pull
settings from the driver, so that it's really only possible to turn
the pull on or off, but it not being possible to determine any
pull settings from software.
Also the binding-documentation for the pull arguments did not match
the changes to the expected values.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
It is counter-intuitive to have "0" mean disable in a boolean
manner for electronic properties of pins such as pull-up and
pull-down. Therefore, define that a pull-up/pull-down argument
of 0 to such a generic option means that the pin is
short-circuited to VDD or GROUND. Pull disablement shall be
done using PIN_CONFIG_BIAS_DISABLE.
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by Heiko Stuebner <heiko@sntech.de>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
There exist controllers that don't support to set the pull to up or down
separately but instead automatically set the pull direction based on
embedded knowledge inside the controller, for example depending on the
selected mux function of the pin.
Therefore this patch adds another config option to use this default
pull-state for a pin where it is not possible to know or decide if the
pin will be pulled up or down.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add a new PIN_CONFIG_BIAS_BUS_HOLD pin configuration for a bus holder
pin mode (also known as bus keeper, or repeater). This is a weak latch
which drives the last value on a tristate bus. Another device on the bus
can drive the bus high or low before going tristate to change the value
driven by the pin.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Rename PIN_CONFIG_INPUT_SCHMITT_DISABLE to
PIN_CONFIG_INPUT_SCHMITT_ENABLE. It's used to make it more generialize.
Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Some pin configurations IP allows to set the current output to the pin.
This patch adds such a parameter to the pinconf-generic mechanism.
This parameter takes as argument the drive strength in mA.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds a definition of a generic output configuration
for a certain pin when using the generic pin configuration
library. Whereas driving pins low/high is usually a GPIO
business, you may want to set up pins into a default state
using hogs, and never touch them again. This helps out
with that scenario.
Based on a patch from Patrice Chotard.
Signed-off-by: Patrice Chotard <patrice.chotard@stericsson.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
In Marvell PXA/MMP silicons, input schmitt disable value is 0x40, not 0.
So append new config parameter -- input schmitt disable.
Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This is a split-off from the earlier patch set which adds generic
pin configuration for the pin controllers that want it. Since
we may have a system with mixed generic and custom pin controllers,
we pass a boolean in the pin controller ops vtable to indicate
if it is generic.
ChangeLog v1->v5:
- Follow parent patch versioning number system.
- Document the semantic meaning of return values from pin config
get functions, so we can iterate over pins and check their
properties from debugfs as part of the generic config code.
- Use proper cast functions in the generic debugfs pin config
file.
- Expand generic config to optionally cover groups too.
ChangeLog v5->v6:
- Update to match underlying changes.
ChangeLog v6->v7:
- Drop DRIVE_OFF parameter, use bias high impedance for this
- Delete argument for drive modes push-pull, od and os. These
are now just state transitions.
- Delete slew rate rising/falling due to discussions on on
proper semantics
- Drop config wakeup, struct irq_chip does this for now, add
back if need be.
- Set PIN_CONFIG_END to 0x7fff making room for custom config
parameters from 0x8000 and up.
- Prefix accessor functions with pinconf_
Andrew Jeffery