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>
Add device managed APIs devm_pinctrl_register() and
devm_pinctrl_unregister() for the APIs pinctrl_register()
and pinctrl_unregister().
This helps in reducing code in error path and sometimes
removal of .remove callback for driver unbind.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
For pinctrl the "default" state is applied to pins before the driver's
probe function is called. This is normally a sensible thing to do,
but in some cases can cause problems. That's because the pins will
change state before the driver is given a chance to program how those
pins should behave.
As an example you might have a regulator that is controlled by a PWM
(output high = high voltage, output low = low voltage). The firmware
might leave this pin as driven high. If we allow the driver core to
reconfigure this pin as a PWM pin before the PWM's probe function runs
then you might end up running at too low of a voltage while we probe.
Let's introudce a new "init" state. If this is defined we'll set
pinctrl to this state before probe and then "default" after probe
(unless the driver explicitly changed states already).
An alternative idea that was thought of was to use the pre-existing
"sleep" or "idle" states and add a boolean property that we should
start in that mode. This was not done because the "init" state is
needed for correctness and those other states are only present (and
only transitioned in to and out of) when (optional) power management
is enabled.
Changes in v3:
- Moved declarations to pinctrl/devinfo.h
- Fixed author/SoB
Changes in v2:
- Added comment to pinctrl_init_done() as per Linus W.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Caesar Wang <wxt@rock-chips.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>
Only this member, pins, is defined as "struct ... const *", but the
others in this struct, pinlops, pmxops, confops, etc. are defined as
"const struct ... *".
Swap the "struct pinctrl_pin_desc" and "const" for consistency.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This "const" claims the get_function_groups callback never
changes the given num_groups pointer. It is always true
in C language, so not worth mentioning.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
While the pinmux_ops are ideally just a vtable for pin mux
calls, the "strict" setting belongs so intuitively with the
pin multiplexing that we should move it here anyway. Putting
it in the top pinctrl_desc makes no sense.
Cc: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Disallow simultaneous use of the the GPIO and peripheral mux
functions by setting a flag "strict" in struct pinctrl_desc.
The blackfin pinmux and gpio controller doesn't allow user to
set up a pin for both GPIO and peripheral function. So, add flag
strict in struct pinctrl_desc to check both gpio_owner and
mux_owner before approving the pin request.
v2-changes:
- if strict flag is set, check gpio_owner and mux_onwer in if and
else clause
v3-changes:
- add kerneldoc for this struct
- augment Documentation/pinctrl.txt
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This reverts commit 5a7d2efdd9.
As per discussion on the mailing list, this is not the right
thing to do. NULL cookies are valid in the stubs.
Reported-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
These functions are supposed to return an error pointer, not NULL.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.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>
commit 2243a87d90
"pinctrl: avoid duplicated calling enable_pinmux_setting for a pin"
removed the .disable callback from the struct pinmux_ops,
making the .enable() callback the only remaining callback.
However .enable() is a bad name as it seems to imply that a
muxing can also be disabled. Rename the callback to .set_mux()
and also take this opportunity to clean out any remaining
mentions of .disable() from the documentation.
Acked-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Acked-by: Fan Wu <fwu@marvell.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
What the patch does:
1. Call pinmux_disable_setting ahead of pinmux_enable_setting
each time pinctrl_select_state is called
2. Remove the HW disable operation in pinmux_disable_setting function.
3. Remove the disable ops in struct pinmux_ops
4. Remove all the disable ops users in current code base.
Notes:
1. Great thanks for the suggestion from Linus, Tony Lindgren and
Stephen Warren and Everyone that shared comments on this patch.
2. The patch also includes comment fixes from Stephen Warren.
The reason why we do this:
1. To avoid duplicated calling of the enable_setting operation
without disabling operation inbetween which will let the pin
descriptor desc->mux_usecount increase monotonously.
2. The HW pin disable operation is not useful for any of the
existing platforms.
And this can be used to avoid the HW glitch after using the
item #1 modification.
In the following case, the issue can be reproduced:
1. There is a driver that need to switch pin state dynamically,
e.g. between "sleep" and "default" state
2. The pin setting configuration in a DTS node may be like this:
component a {
pinctrl-names = "default", "sleep";
pinctrl-0 = <&a_grp_setting &c_grp_setting>;
pinctrl-1 = <&b_grp_setting &c_grp_setting>;
}
The "c_grp_setting" config node is totally identical, maybe like
following one:
c_grp_setting: c_grp_setting {
pinctrl-single,pins = <GPIO48 AF6>;
}
3. When switching the pin state in the following official pinctrl
sequence:
pin = pinctrl_get();
state = pinctrl_lookup_state(wanted_state);
pinctrl_select_state(state);
pinctrl_put();
Test Result:
1. The switch is completed as expected, that is: the device's
pin configuration is changed according to the description in the
"wanted_state" group setting
2. The "desc->mux_usecount" of the corresponding pins in "c_group"
is increased without being decreased, because the "desc" is for
each physical pin while the setting is for each setting node
in the DTS.
Thus, if the "c_grp_setting" in pinctrl-0 is not disabled ahead
of enabling "c_grp_setting" in pinctrl-1, the desc->mux_usecount
will keep increasing without any chance to be decreased.
According to the comments in the original code, only the setting,
in old state but not in new state, will be "disabled" (calling
pinmux_disable_setting), which is correct logic but not intact. We
still need consider case that the setting is in both old state
and new state. We can do this in the following two ways:
1. Avoid to "enable"(calling pinmux_enable_setting) the "same pin
setting" repeatedly
2. "Disable"(calling pinmux_disable_setting) the "same pin setting",
actually two setting instances, ahead of enabling them.
Analysis:
1. The solution #2 is better because it can avoid too much
iteration.
2. If we disable all of the settings in the old state and one of
the setting(s) exist in the new state, the pins mux function
change may happen when some SoC vendors defined the
"pinctrl-single,function-off"
in their DTS file.
old_setting => disabled_setting => new_setting.
3. In the pinmux framework, when a pin state is switched, the
setting in the old state should be marked as "disabled".
Conclusion:
1. To Remove the HW disabling operation to above the glitch mentioned
above.
2. Handle the issue mentioned above by disabling all of the settings
in old state and then enable the all of the settings in new state.
Signed-off-by: Fan Wu <fwu@marvell.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Maxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
drv_data is added to the pinctrl_pin_desc for drivers to define additional
driver-specific per-pin data.
Signed-off-by: Sherman Yin <syin@broadcom.com>
Reviewed-by: Christian Daudt <bcm@fixthebug.org>
Reviewed-by: Matt Porter <matt.porter@linaro.org>
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>
This patch adds the infrastructure required to register non-linear gpio
ranges through gpiolib and the standard GPIO device tree bindings.
Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
When setting pin configuration in the pinctrl framework, pin_config_set() or
pin_config_group_set() is called in a loop to set one configuration at a time
for the specified pin or group.
This patch 1) removes the loop and 2) changes the API to pass the whole pin
config array to the driver. It is now up to the driver to loop through the
configs. This allows the driver to potentially combine configs and reduce the
number of writes to pin config registers.
All c files changed have been build-tested to verify the change compiles and
that the corresponding .o is successfully generated.
Signed-off-by: Sherman Yin <syin@broadcom.com>
Reviewed-by: Christian Daudt <csd@broadcom.com>
Reviewed-by: Matt Porter <matt.porter@linaro.org>
Tested-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.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>
From the inception ot the pin config API there has been the
possibility to get a handle at a pin directly and configure
its electrical characteristics. For this reason we had:
int pin_config_get(const char *dev_name, const char *name,
unsigned long *config);
int pin_config_set(const char *dev_name, const char *name,
unsigned long config);
int pin_config_group_get(const char *dev_name,
const char *pin_group,
unsigned long *config);
int pin_config_group_set(const char *dev_name,
const char *pin_group,
unsigned long config);
After the introduction of the pin control states that will
control pins associated with devices, and its subsequent
introduction to the device core, as well as the
introduction of pin control hogs that can set up states on
boot and optionally also at sleep, this direct pin control
API is a thing of the past.
As could be expected, it has zero in-kernel users.
Let's delete this API and make our world simpler.
Reported-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The kerneldoc comment for struct pinconf_ops was missing
pin_config_dbg_parse_modify, and instead described
pin_config_group_dbg_set (which is presumably an old name for the same
function). Rename it in the kerneldoc comment so they match.
Signed-off-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>
The comment introduced with the recently added pinctrl_gpio_range.pins
element was wrong. This corrects it.
Thanks to Patrice Chotard for pointing this out.
Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The stubs for the !PINCTRL case were placed in the wrong
part of the file, causing breakage in linux-next when compiling
SH without pinctrl. Fix it up by moving the stubs to the right
place.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Traditionally, GPIO ranges are based on consecutive ranges of both GPIO
and pin numbers. This patch allows for GPIO ranges with arbitrary lists
of pin numbers.
Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
If a device have sleep and idle states in addition to the
default state, look up these in the core and stash them in
the pinctrl state container.
Add accessor functions for pinctrl consumers to put the pins
into "default", "sleep" and "idle" states passing nothing but
the struct device * affected.
Solution suggested by Kevin Hilman, Mark Brown and Dmitry
Torokhov in response to a patch series from Hebbar
Gururaja.
Cc: Hebbar Gururaja <gururaja.hebbar@ti.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
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>
This update adds a debugfs interface to modify a pin configuration
for a given state in the pinctrl map. This allows to modify the
configuration for a non-active state, typically sleep state.
This configuration is not applied right away, but only when the state
will be entered.
This solution is mandated for us by HW validation: in order
to test and verify several pin configurations during sleep without
recompiling the software.
Change log in this patch set;
Take into account latest feedback from Stephen Warren:
- stale comments update
- improved code efficiency and readibility
- limit size of global variable pinconf_dbg_conf
- remove req_type as it can easily be added later when
add/delete requests support is implemented
Signed-off-by: Laurent Meunier <laurent.meunier@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The pinconf, pinctrl and pinmux operation structures hold function
pointers that are never modified. Declare them as const.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
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>
This makes the device core auto-grab the pinctrl handle and set
the "default" (PINCTRL_STATE_DEFAULT) state for every device
that is present in the device model right before probe. This will
account for the lion's share of embedded silicon devcies.
A modification of the semantics for pinctrl_get() is also done:
previously if the pinctrl handle for a certain device was already
taken, the pinctrl core would return an error. Now, since the
core may have already default-grabbed the handle and set its
state to "default", if the handle was already taken, this will
be disregarded and the located, previously instanitated handle
will be returned to the caller.
This way all code in drivers explicitly requesting their pinctrl
handlers will still be functional, and drivers that want to
explicitly retrieve and switch their handles can still do that.
But if the desired functionality is just boilerplate of this
type in the probe() function:
struct pinctrl *p;
p = devm_pinctrl_get_select_default(&dev);
if (IS_ERR(p)) {
if (PTR_ERR(p) == -EPROBE_DEFER)
return -EPROBE_DEFER;
dev_warn(&dev, "no pinctrl handle\n");
}
The discussion began with the addition of such boilerplate
to the omap4 keypad driver:
http://marc.info/?l=linux-input&m=135091157719300&w=2
A previous approach using notifiers was discussed:
http://marc.info/?l=linux-kernel&m=135263661110528&w=2
This failed because it could not handle deferred probes.
This patch alone does not solve the entire dilemma faced:
whether code should be distributed into the drivers or
if it should be centralized to e.g. a PM domain. But it
solves the immediate issue of the addition of boilerplate
to a lot of drivers that just want to grab the default
state. As mentioned, they can later explicitly retrieve
the handle and set different states, and this could as
well be done by e.g. PM domains as it is only related
to a certain struct device * pointer.
ChangeLog v4->v5 (Stephen):
- Simplified the devicecore grab code.
- Deleted a piece of documentation recommending that pins
be mapped to a device rather than hogged.
ChangeLog v3->v4 (Linus):
- Drop overzealous NULL checks.
- Move kref initialization to pinctrl_create().
- Seeking Tested-by from Stephen Warren so we do not disturb
the Tegra platform.
- Seeking ACK on this from Greg (and others who like it) so I
can merge it through the pinctrl subsystem.
ChangeLog v2->v3 (Linus):
- Abstain from using IS_ERR_OR_NULL() in the driver core,
Russell recently sent a patch to remove it. Handle the
NULL case explicitly even though it's a bogus case.
- Make sure we handle probe deferral correctly in the device
core file. devm_kfree() the container on error so we don't
waste memory for devices without pinctrl handles.
- Introduce reference counting into the pinctrl core using
<linux/kref.h> so that we don't release pinctrl handles
that have been obtained for two or more places.
ChangeLog v1->v2 (Linus):
- Only store a pointer in the device struct, and only allocate
this if it's really used by the device.
Cc: Felipe Balbi <balbi@ti.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Mitch Bradley <wmb@firmworks.com>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Rickard Andersson <rickard.andersson@stericsson.com>
Cc: Russell King <linux@arm.linux.org.uk>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
[swarren: fixed and simplified error-handling in pinctrl_bind_pins(), to
correctly handle deferred probe. Removed admonition from docs not to use
pinctrl hogs for devices]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add new function to get devname from pinctrl_dev. pinctrl_dev_get_name()
can only get pinctrl description name. If we want to use gpio driver to
find pinctrl device node, we need to fetch the pinctrl device name.
Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
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 adds a function to the pinctrl core to retrieve the GPIO
range associated with a certain pin for a certain controller.
This is needed when a pinctrl driver want to look up the
corresponding struct gpio_chip for a certain pin. As the
GPIO drivers can now create these ranges themselves, the
pinctrl driver no longer knows about all its associated GPIO
chips.
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Rename the function find_pinctrl_and_add_gpio_range()
to pinctrl_find_and_add_gpio_range() so as to be consistent
with the rest of the functions.
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The fact that of_gpiochip_add_pin_range() and
gpiochip_add_pin_range() share too much code is fragile and
will invariably mean that bugs need to be fixed in two places
instead of one.
So separate the concerns of gpiolib.c and gpiolib-of.c and
have the latter call the former as back-end. This is necessary
also when going forward with other device descriptions such
as ACPI.
This is done by:
- Adding a return code to gpiochip_add_pin_range() so we can
reliably check whether this succeeds.
- Get rid of the custom of_pinctrl_add_gpio_range() from
pinctrl. Instead create of_pinctrl_get() to just retrive the
pin controller per se from an OF node. This composite
function was just begging to be deleted, it was way to
purpose-specific.
- Use pinctrl_dev_get_name() to get the name of the retrieved
pin controller and use that to call back into the generic
gpiochip_add_pin_range().
Now the pin range is only allocated and tied to a pin
controller from the core implementation in gpiolib.c.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
pinctrl subsystem needs gpio chip base to prepare set of gpio
pin ranges, which a given pinctrl driver can handle. This is
important to handle pinctrl gpio request calls in order to
program a given pin properly for gpio operation.
As gpio base is allocated dynamically during gpiochip
registration, presently there exists no clean way to pass this
information to the pinctrl subsystem.
After few discussions from [1], it was concluded that may be
gpio controller reporting the pin range it supports, is a
better way than pinctrl subsystem directly registering it.
[1] http://comments.gmane.org/gmane.linux.ports.arm.kernel/184816
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
[Edited documentation a bit]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Jon Hunter