pinctrl_find_gpio_range_from_pin takes the pctldev->mutex but so
does pinconf_pins_show and this will cause a deadlock if
pinctrl_find_gpio_range_from_pin is used in .pin_config_get
callback.
Create a nolock version of pinctrl_find_gpio_range_from_pin to
allow pin to gpio lookup to be used from pinconf_pins_show.
Signed-off-by: Joachim Eastwood <manabian@gmail.com>
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>
If the gpio driver is confused about the numbers for gpio-ranges,
pinctrl_ready_for_gpio_range() may get called with invalid GPIO
causing a NULL pointer exception. Let's instead provide a warning
that allows fixing the problem and return with error.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Use dev_err() rather than pr_err() to display the error message.
(Besides, dev_err() is already used 7 lines below in this function.)
Also, drop the redundant information "on %s" because dev_err() shows
which device the message is related to.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
- Core functionality:
- Enable exclusive pin ownership: it is possible to flag a pin
controller so that GPIO and other functions cannot use a single
pin simultaneously.
- New drivers:
- NXP LPC18xx System Control Unit pin controller
- Imagination Pistachio SoC pin controller
- New subdrivers:
- Freescale i.MX7d SoC
- Intel Sunrisepoint-H PCH
- Renesas PFC R8A7793
- Renesas PFC R8A7794
- Mediatek MT6397, MT8127
- SiRF Atlas 7
- Allwinner A33
- Qualcomm MSM8660
- Marvell Armada 395
- Rockchip RK3368
- Cleanups:
- A big cleanup of the Marvell MVEBU driver rectifying it to
correspond to reality
- Drop platform device probing from the SH PFC driver, we are now a
DT only shop for SuperH
- Drop obsolte multi-platform check for SH PFC
- Various janitorial: constification, grammar etc
- Improvements:
- The AT91 GPIO portions now supports the set_multiple() feature
- Split out SPI pins on the Xilinx Zynq
- Support DTs without specific function nodes in the i.MX driver
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Merge tag 'pinctrl-v4.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull pin control updates from Linus Walleij:
"Here is the bulk of pin control changes for the v4.2 series: Quite a
lot of new SoC subdrivers and two new main drivers this time, apart
from that business as usual.
Details:
Core functionality:
- Enable exclusive pin ownership: it is possible to flag a pin
controller so that GPIO and other functions cannot use a single pin
simultaneously.
New drivers:
- NXP LPC18xx System Control Unit pin controller
- Imagination Pistachio SoC pin controller
New subdrivers:
- Freescale i.MX7d SoC
- Intel Sunrisepoint-H PCH
- Renesas PFC R8A7793
- Renesas PFC R8A7794
- Mediatek MT6397, MT8127
- SiRF Atlas 7
- Allwinner A33
- Qualcomm MSM8660
- Marvell Armada 395
- Rockchip RK3368
Cleanups:
- A big cleanup of the Marvell MVEBU driver rectifying it to
correspond to reality
- Drop platform device probing from the SH PFC driver, we are now a
DT only shop for SuperH
- Drop obsolte multi-platform check for SH PFC
- Various janitorial: constification, grammar etc
Improvements:
- The AT91 GPIO portions now supports the set_multiple() feature
- Split out SPI pins on the Xilinx Zynq
- Support DTs without specific function nodes in the i.MX driver"
* tag 'pinctrl-v4.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (99 commits)
pinctrl: rockchip: add support for the rk3368
pinctrl: rockchip: generalize perpin driver-strength setting
pinctrl: sh-pfc: r8a7794: add SDHI pin groups
pinctrl: sh-pfc: r8a7794: add MMCIF pin groups
pinctrl: sh-pfc: add R8A7794 PFC support
pinctrl: make pinctrl_register() return proper error code
pinctrl: mvebu: armada-39x: add support for Armada 395 variant
pinctrl: mvebu: armada-39x: add missing SATA functions
pinctrl: mvebu: armada-39x: add missing PCIe functions
pinctrl: mvebu: armada-38x: add ptp functions
pinctrl: mvebu: armada-38x: add ua1 functions
pinctrl: mvebu: armada-38x: add nand functions
pinctrl: mvebu: armada-38x: add sata functions
pinctrl: mvebu: armada-xp: add dram functions
pinctrl: mvebu: armada-xp: add nand rb function
pinctrl: mvebu: armada-xp: add spi1 function
pinctrl: mvebu: armada-39x: normalize ref clock naming
pinctrl: mvebu: armada-xp: rename spi to spi0
pinctrl: mvebu: armada-370: align spi1 clock pin naming
pinctrl: mvebu: armada-370: align VDD cpu-pd pin naming with datasheet
...
Currently, pinctrl_register() just returns NULL on error, so the
callers can not know the exact reason of the failure.
Some of the pinctrl drivers return -EINVAL, some -ENODEV, and some
-ENOMEM on error of pinctrl_register(), although the error code
might be different from the real cause of the error.
This commit reworks pinctrl_register() to return the appropriate
error code and modifies all of the pinctrl drivers to use IS_ERR()
for the error checking and PTR_ERR() for getting the error code.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Lee Jones <lee@kernel.org>
Acked-by: Sören Brinkmann <soren.brinkmann@xilinx.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Ray Jui <rjui@broadcom.com>
Acked-by: Antoine Tenart <antoine.tenart@free-electrons.com>
Acked-by: Hongzhou Yang <hongzhou.yang@mediatek.com>
Acked-by: Wei Chen <Wei.Chen@csr.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
There are two types for pinctrl maps: pinmux and pinconfig
This debug message shows the number of maps of both types.
The string "pinmux map" is not precise. Let's say "pinctrl map"
instead.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
[also fixed %d -> %u]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Way back, when the world was a simpler place and there was no war, no
evil, and no kernel bugs, there was just a single pinctrl lock. That
was how the world was when (57291ce pinctrl: core device tree mapping
table parsing support) was written. In that case, there were
instances where the pinctrl mutex was already held when
pinctrl_register_map() was called, hence a "locked" parameter was
passed to the function to indicate that the mutex was already locked
(so we shouldn't lock it again).
A few years ago in (42fed7b pinctrl: move subsystem mutex to
pinctrl_dev struct), we switched to a separate pinctrl_maps_mutex.
...but (oops) we forgot to re-think about the whole "locked" parameter
for pinctrl_register_map(). Basically the "locked" parameter appears
to still refer to whether the bigger pinctrl_dev mutex is locked, but
we're using it to skip locks of our (now separate) pinctrl_maps_mutex.
That's kind of a bad thing(TM). Probably nobody noticed because most
of the calls to pinctrl_register_map happen at boot time and we've got
synchronous device probing. ...and even cases where we're
asynchronous don't end up actually hitting the race too often. ...but
after banging my head against the wall for a bug that reproduced 1 out
of 1000 reboots and lots of looking through kgdb, I finally noticed
this.
Anyway, we can now safely remove the "locked" parameter and go back to
a war-free, evil-free, and kernel-bug-free world.
Fixes: 42fed7ba44 ("pinctrl: move subsystem mutex to pinctrl_dev struct")
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch is to fix two deadlock cases.
Deadlock 1:
CPU #1
pinctrl_register-> pinctrl_get ->
create_pinctrl
(Holding lock pinctrl_maps_mutex)
-> get_pinctrl_dev_from_devname
(Trying to acquire lock pinctrldev_list_mutex)
CPU #0
pinctrl_unregister
(Holding lock pinctrldev_list_mutex)
-> pinctrl_put ->> pinctrl_free ->
pinctrl_dt_free_maps -> pinctrl_unregister_map
(Trying to acquire lock pinctrl_maps_mutex)
Simply to say
CPU#1 is holding lock A and trying to acquire lock B,
CPU#0 is holding lock B and trying to acquire lock A.
Deadlock 2:
CPU #3
pinctrl_register-> pinctrl_get ->
create_pinctrl
(Holding lock pinctrl_maps_mutex)
-> get_pinctrl_dev_from_devname
(Trying to acquire lock pinctrldev_list_mutex)
CPU #2
pinctrl_unregister
(Holding lock pctldev->mutex)
-> pinctrl_put ->> pinctrl_free ->
pinctrl_dt_free_maps -> pinctrl_unregister_map
(Trying to acquire lock pinctrl_maps_mutex)
CPU #0
tegra_gpio_request
(Holding lock pinctrldev_list_mutex)
-> pinctrl_get_device_gpio_range
(Trying to acquire lock pctldev->mutex)
Simply to say
CPU#3 is holding lock A and trying to acquire lock D,
CPU#2 is holding lock B and trying to acquire lock A,
CPU#0 is holding lock D and trying to acquire lock B.
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Jim Lin <jilin@nvidia.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>
Commit c420619 "pinctrl: pinconf: remove checks on ops->pin_config_get"
removed the check on (ops != NULL) when performing pinconf_pins_show() or
pinconf_groups_show(). As these entries are always enabled, even if
pinconf is not supported, reading will result in an oops due to NULL
ops.
Instead of checking for ops, remove the corresponding debugfs entries if
pinconf and/or pinmux are not implemented.
Tested on OMAP3 (pinctrl-single).
Cc: stable@vger.kernel.org
Signed-off-by: Florian Vaussard <florian.vaussard@epfl.ch>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
We have few fedora bug reports about list corruption on pinctrl,
for example:
https://bugzilla.redhat.com/show_bug.cgi?id=1051918
Most likely corruption happen due lack of protection of pinctrl_list
when adding new nodes to it. Patch corrects that.
Fixes: 42fed7ba44 ("pinctrl: move subsystem mutex to pinctrl_dev struct")
Cc: stable@vger.kernel.org
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Stephen Warren <swarren@nvidia.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>
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Merge tag 'v3.11-rc7' into devel
Merged in this to avoid conflicts with the big locking fixes
from upstream.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Conflicts:
drivers/pinctrl/pinctrl-sunxi.c
This one is missed in commit 42fed7ba "pinctrl: move subsystem mutex to
pinctrl_dev struct".
I think this fixes the race between pin_free() and pin_request() calls.
It protects accessing the members of pctldev->desc.
(e.g. update desc->mux_usecount, desc->gpio_owner, desc->mux_owner, etc)
Current code grabs pctldev->mutex before calling pinmux_free_gpio(),
but did not grab the mutex while calling pinmux_request_gpio().
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The implementation in pinctrl_register_one_pin() ensures pindesc->name is always
not NULL before insert the pindesc to radix tree.
If the desc return from pin_desc_get is not NULL, desc->name is always not NULL.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Hold pctldev->mutex mutex_lock when traverse the list.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This one is missed in commit 44d5f7bb "pinctrl: sink pinctrldev_list_mutex".
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
We forgot to free the node itself when free:ing a map.
Reported-by: xulinuxkernel <xulinuxkernel@gmail.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
There's no need to duplicate essentially the same functions. Let's
introduce static int pinctrl_pm_select_state() and make the other
related functions call that.
This allows us to add support later on for multiple active states,
and more optimized dynamic remuxing.
Note that we still need to export the various pinctrl_pm_select
functions as we want to keep struct pinctrl_state private to the
pinctrl code, and cannot replace those with inline functions.
Cc: Felipe Balbi <balbi@ti.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Symbols referenced only in this file are made static.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add the missing unlock before return from function pinctrl_find_gpio_range_from_pin()
in the error handling case.
Introduced by commit 2ff3477efd7086544b9e298fc63afab0645921b4.
(pinctrl: add pin list based GPIO ranges)
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The three functions pinctrl_pm_select_default_state,
pinctrl_pm_select_sleep_state, and pinctrl_pm_select_idle_state
are used in drivers that can be loadable modules, and should
be exported.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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>
The pinctrldev_list_mutex is sinked into the functions that
actually traverse the list and lock it there. The code makes
much more sense in this way. All the callers are in
non-performance critical paths and the code is way more
readable this way.
Also refactor the function get_pinctrl_dev_from_devname() to
follow the design pattern of get_pinctrl_dev_from_of_node()
which is slightly simpler.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This obvious bug was introduced by d755910b7 ("pinctrl: move subsystem
mutex to pinctrl_dev struct").
Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This mutex avoids deadlock in case of use of multiple pin
controllers. Before this modification, by using a global
mutex, deadlock appeared when, for example, a call to
pinctrl_pins_show() locked the pinctrl_mutex, called the
ops->pin_dbg_show of a particular pin controller. If this
pin controller needs I2C access to retrieve configuration
information and I2C driver is using pinctrl to drive its
pins, a call to pinctrl_select_state() try to lock again
pinctrl_mutex which leads to a deadlock.
Notice that the mutex grab from the two direction functions
was moved into pinctrl_gpio_direction().
For several cases, we can't replace pinctrl_mutex by
pctldev->mutex, because at this stage, pctldev is
not accessible :
- pinctrl_get()/pinctrl_put()
- pinctrl_register_maps()
So add respectively pinctrl_list_mutex and
pinctrl_maps_mutex in order to protect
pinctrl_list and pinctrl_maps list instead.
Reintroduce pinctrldev_list_mutex in
find_pinctrl_by_of_node(),
pinctrl_find_and_add_gpio_range()
pinctrl_request_gpio(), pinctrl_free_gpio(),
pinctrl_gpio_direction(), pinctrl_devices_show(),
pinctrl_register() and pinctrl_unregister() to
protect pinctrldev_list.
Changes v2->v3:
- Fix a missing EXPORT_SYMBOL_GPL() for pinctrl_select_state().
Changes v1->v2:
- pinctrl_select_state_locked() is removed, all lock mechanism
is located inside pinctrl_select_state(). When parsing
the state->setting list, take the per-pin-controller driver
lock. (Patrice).
- Introduce pinctrldev_list_mutex to protect pinctrldev_list
in all functions which parse or modify pictrldev_list.
(Patrice).
- move find_pinctrl_by_of_node() from pinctrl/devicetree.c to
pinctrl/core.c in order to protect pinctrldev_list.
(Patrice).
- Sink mutex:es into some functions and remove some _locked
variants down to where the lists are actually accessed to
make things simpler. (Linus)
- Drop *all* mutexes completely from pinctrl_lookup_state()
and pinctrl_select_state() - no relevant mutex was taken
and it was unclear what this was protecting against. (Linus)
Reported by : Seraphin Bonnaffe <seraphin.bonnaffe@stericsson.com>
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Instead of just enabling the settings that were disabled in the 1st
loop, it's simpler to recall pinctrl_select_state with the old state.
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
As Stephen Warren pointed out, pinctrl_free_setting() was called instead
of pinmux_disable_setting() on error.
In this error code, we want to call pinmux_disable_setting() where
pinmux_enable_setting() was called.
And when pinconf_apply_setting() was called, we can't do much to undo
the pin muxing (the closest thing I can think about for "unmuxing" a pin
is muxing it as GPIO input).
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
In unapply_new_state, the old state is re-applied, but p->state is not
set back as it should.
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
As Stephen Warren suggested, checking first if the setting->node entry
is the first in the list or not is superfluous, as it is checked again
in the list_for_each_entry bellow.
So, remove it, the code will be simpler and lighter !
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
In file included from drivers/pinctrl/core.c:30:0:
include/asm-generic/gpio.h: In function 'gpio_get_value_cansleep':
include/asm-generic/gpio.h:270:2: error: implicit declaration of
function '__gpio_get_value' [-Werror=implicit-function-declaration]
include/asm-generic/gpio.h: In function 'gpio_set_value_cansleep':
include/asm-generic/gpio.h:276:2: error: implicit declaration of
function '__gpio_set_value' [-Werror=implicit-function-declaration]
drivers/pinctrl/core.c: In function 'pinctrl_ready_for_gpio_range':
drivers/pinctrl/core.c:297:9: error: implicit declaration of function
'gpio_to_chip' [-Werror=implicit-function-declaration]
drivers/pinctrl/core.c:297:27: warning: initialization makes pointer
from integer without a cast [enabled by default]
drivers/pinctrl/core.c:304:45: error: dereferencing pointer to
incomplete type
drivers/pinctrl/core.c:305:26: error: dereferencing pointer to
incomplete type
drivers/pinctrl/core.c:305:39: error: dereferencing pointer to
incomplete type
cc1: some warnings being treated as errors
make[2]: *** [drivers/pinctrl/core.o] Error 1
make[1]: *** [drivers/pinctrl] Error 2
make[1]: *** Waiting for unfinished jobs....
It's caused by CONFIG_GPIOLIB isn't enabled for some platform. So
add the dependence on pinctrl_ready_for_gpio_range().
Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
If a new state is applied, the groups configured in the old state but
not in the new state are disabled.
If something goes wrong and the new state can't be applied, we have to
re-enable those groups.
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
If enabling a pin fails in pinctrl_select_state_locked(), all the
previous enabled pins have to be disabled to get back to the previous
state.
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This prepares the implementation of pinctrl_select_state_locked() free code.
No functionnal change.
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
pinctrl_get_device_gpio_range() only checks whether a certain GPIO pin
is in gpio range. But maybe some GPIO pins don't have back-end pinctrl
interface, it means that these pins are always configured as GPIO
function. For example, gpio159 isn't related to back-end pinctrl device
in Hi3620 while other GPIO pins are related to back-end pinctrl device.
Append pinctrl_ready_for_gpio_range() that is used to check whether
pinctrl device with GPIO range is ready. This function will be called
after pinctrl_get_device_gpio_range() fails.
If pinctrl device with GPIO range is found, it means that pinctrl device
is already launched and a certain GPIO pin just don't have back-end pinctrl
interface. Then pinctrl_request_gpio() shouldn't return -EPROBE_DEFER in
this case.
Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
devres_release() can simplify the code, because devres_release()
will call the destructor for the resource as well as freeing
the devres data.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
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.
Signed-off-by: Laurent Meunier <laurent.meunier@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
'pinctrl_release' is used only in this file. Hence make it static.
Without this patch we get the following sparse error:
drivers/pinctrl/core.c:815:6: warning:
symbol 'pinctrl_release' was not declared. Should it be static?
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
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>
This fix allows handling sleep mode for hogged
pins in pinctrl. It provides functions to set pins
to sleep/default configurations according to their
current state.
Signed-off-by: Julien Delacou <julien.delacou@stericsson.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Up until now, as hogs were always taken at the end of the
pin control device registration, it didn't cause any problem.
But when starting to hog pins from the device core it will
cause deferral of the pin controller device itself since the
default pin fetch is done *before* the device probes, so
let's fix this annoyance (which is also aesthetically ugly).
Also take some care to make sure that if any one map entry
results in a deferral rather than a failure, then that
deferral will take precedence.
Reviewed-by: Stephen Warren <swarren@nvidia.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>
This makes the pinctrl_find_and_add_gpio_range() return
-EPROBE_DEFER if the range hosting pin controller cannot be
located. We may assume that the common case for why adding a
range fails is that the targe pin controller device has not
probed yet.
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
