Commit graph

156 commits

Author SHA1 Message Date
Linus Walleij
d77552d93c Merge branch 'ib-pinctrl-unreg-mappings' into devel 2019-12-30 14:27:53 +01:00
Hans de Goede
c72bed23b9 pinctrl: Allow modules to use pinctrl_[un]register_mappings
Currently only the drivers/pinctrl/devicetree.c code allows registering
pinctrl-mappings which may later be unregistered, all other mappings
are assumed to be permanent.

Non-dt platforms may also want to register pinctrl mappings from code which
is build as a module, which requires being able to unregister the mapping
when the module is unloaded to avoid dangling pointers.

To allow unregistering the mappings the devicetree code uses 2 internal
functions: pinctrl_register_map and pinctrl_unregister_map.

pinctrl_register_map allows the devicetree code to tell the core to
not memdup the mappings as it retains ownership of them and
pinctrl_unregister_map does the unregistering, note this only works
when the mappings where not memdupped.

The only code relying on the memdup/shallow-copy done by
pinctrl_register_mappings is arch/arm/mach-u300/core.c this commit
replaces the __initdata with const, so that the shallow-copy is no
longer necessary.

After that we can get rid of the internal pinctrl_unregister_map function
and just use pinctrl_register_mappings directly everywhere.

This commit also renames pinctrl_unregister_map to
pinctrl_unregister_mappings so that its naming matches its
pinctrl_register_mappings counter-part and exports it.

Together these 2 changes will allow non-dt platform code to
register pinctrl-mappings from modules without breaking things on
module unload (as they can now unregister the mapping on unload).

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20191216205122.1850923-2-hdegoede@redhat.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-12-30 14:27:17 +01:00
Ulf Hansson
55d54d1ee8 pinctrl: core: Add pinctrl_select_default_state() and export it
It has turned out that some mmc host drivers, but perhaps also others
drivers, needs to reset the pinctrl into the default state
(PINCTRL_STATE_DEFAULT). However, they can't use the existing
pinctrl_pm_select_default_state(), as that requires CONFIG_PM to be set.
This leads to open coding, as they need to look up the default state
themselves and then select it.

To avoid the open coding, let's introduce pinctrl_select_default_state()
and make it available independently of CONFIG_PM. As a matter of fact, this
makes it more consistent with the behaviour of the driver core, as it
already tries to looks up the default state during probe.

Going forward, users of pinctrl_pm_select_default_state() are encouraged to
move to pinctrl_select_default_state(), so the old API can be removed.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20191206170821.29711-2-ulf.hansson@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-12-13 13:51:06 +01:00
Stefan Wahren
472a61e777 pinctrl/gpio: Take MUX usage into account
The user space like gpioinfo only see the GPIO usage but not the
MUX usage (e.g. I2C or SPI usage) of a pin. As a user we want
to know which pin is free/safe to use. So take the MUX usage of
strict pinmux controllers into account to get a more realistic
view for ioctl GPIO_GET_LINEINFO_IOCTL.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Tested-by: Ramon Fried <rfried.dev@gmail.com>
Signed-off-by: Ramon Fried <rfried.dev@gmail.com>
Link: https://lore.kernel.org/r/20190814110035.13451-1-ramon.fried@linux.intel.com
Acked-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-08-23 11:09:41 +02:00
Linus Torvalds
43c95d3694 This is the bulk of pin control changes for the v5.3 kernel
cycle:
 
 Core changes:
 
 - Device links can optionally be added between a pin control
   producer and its consumers. This will affect how the system
   power management is handled: a pin controller will not suspend
   before all of its consumers have been suspended. This was
   necessary for the ST Microelectronics STMFX expander and
   need to be tested on other systems as well: it makes sense
   to make this default in the long run. Right now it is
   opt-in per driver.
 
 - Drive strength can be specified in microamps. With decreases
   in silicon technology, milliamps isn't granular enough, let's
   make it possible to select drive strengths in microamps. Right
   now the Meson (AMlogic) driver needs this.
 
 New drivers:
 
 - New subdriver for the Tegra 194 SoC.
 
 - New subdriver for the Qualcomm SDM845.
 
 - New subdriver for the Qualcomm SM8150.
 
 - New subdriver for the Freescale i.MX8MN (Freescale is now a
   product line of NXP).
 
 - New subdriver for Marvell MV98DX1135.
 
 Driver improvements:
 
 - The Bitmain BM1880 driver now supports pin config in
   addition to muxing.
 
 - The Qualcomm drivers can now reserve some GPIOs as taken
   aside and not usable for users. This is used in ACPI systems
   to take out some GPIO lines used by the BIOS so that
   noone else (neither kernel nor userspace) will play with them
   by mistake and crash the machine.
 
 - A slew of refurbishing around the Aspeed drivers (board
   management controllers for servers) in preparation for the
   new Aspeed AST2600 SoC.
 
 - A slew of improvements over the SH PFC drivers as usual.
 
 - Misc cleanups and fixes.
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Merge tag 'pinctrl-v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl

Pull pin control updates from Linus Walleij:
 "This is the bulk of pin control changes for the v5.3 kernel cycle:

  Core changes:

   - Device links can optionally be added between a pin control producer
     and its consumers. This will affect how the system power management
     is handled: a pin controller will not suspend before all of its
     consumers have been suspended.

     This was necessary for the ST Microelectronics STMFX expander and
     need to be tested on other systems as well: it makes sense to make
     this default in the long run.

     Right now it is opt-in per driver.

   - Drive strength can be specified in microamps. With decreases in
     silicon technology, milliamps isn't granular enough, let's make it
     possible to select drive strengths in microamps.

     Right now the Meson (AMlogic) driver needs this.

  New drivers:

   - New subdriver for the Tegra 194 SoC.

   - New subdriver for the Qualcomm SDM845.

   - New subdriver for the Qualcomm SM8150.

   - New subdriver for the Freescale i.MX8MN (Freescale is now a product
     line of NXP).

   - New subdriver for Marvell MV98DX1135.

  Driver improvements:

   - The Bitmain BM1880 driver now supports pin config in addition to
     muxing.

   - The Qualcomm drivers can now reserve some GPIOs as taken aside and
     not usable for users. This is used in ACPI systems to take out some
     GPIO lines used by the BIOS so that noone else (neither kernel nor
     userspace) will play with them by mistake and crash the machine.

   - A slew of refurbishing around the Aspeed drivers (board management
     controllers for servers) in preparation for the new Aspeed AST2600
     SoC.

   - A slew of improvements over the SH PFC drivers as usual.

   - Misc cleanups and fixes"

* tag 'pinctrl-v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (106 commits)
  pinctrl: aspeed: Strip moved macros and structs from private header
  pinctrl: aspeed: Fix missed include
  pinctrl: baytrail: Use GENMASK() consistently
  pinctrl: baytrail: Re-use data structures from pinctrl-intel.h
  pinctrl: baytrail: Use defined macro instead of magic in byt_get_gpio_mux()
  pinctrl: qcom: Add SM8150 pinctrl driver
  dt-bindings: pinctrl: qcom: Add SM8150 pinctrl binding
  dt-bindings: pinctrl: qcom: Document missing gpio nodes
  pinctrl: aspeed: Add implementation-related documentation
  pinctrl: aspeed: Split out pinmux from general pinctrl
  pinctrl: aspeed: Clarify comment about strapping W1C
  pinctrl: aspeed: Correct comment that is no longer true
  MAINTAINERS: Add entry for ASPEED pinctrl drivers
  dt-bindings: pinctrl: aspeed: Convert AST2500 bindings to json-schema
  dt-bindings: pinctrl: aspeed: Convert AST2400 bindings to json-schema
  dt-bindings: pinctrl: aspeed: Split bindings document in two
  pinctrl: qcom: Add irq_enable callback for msm gpio
  pinctrl: madera: Fixup SPDX headers
  pinctrl: qcom: sdm845: Fix CONFIG preprocessor guard
  pinctrl: tegra: Add bitmask support for parked bits
  ...
2019-07-13 15:02:27 -07:00
Masahiro Yamada
78b99577b3 pinctrl: remove unused pin_is_valid()
This function was used by pin_request() to pointlessly double-check
the pin validity, and it was the only user ever.

Since commit d2f6a1c6fb ("pinctrl: remove double pin validity
check."), no one has ever used it.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-06-12 09:10:54 +02:00
Masahiro Yamada
6cadafb310 pinctrl: remove unneeded initializer for list_for_each_entry() iterator
The iterator is initialized in list_for_each_entry().

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-06-12 09:09:51 +02:00
Thomas Gleixner
af873fcece treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 194
Based on 1 normalized pattern(s):

  license terms gnu general public license gpl version 2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 161 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170027.447718015@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:29:22 -07:00
Linus Walleij
b672a87ae5 pinctrl: core: Do not add device links for hogs
Hogs would create circular device links, so do not link
the device to itself.

Cc: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-05-24 10:08:04 +02:00
Benjamin Gaignard
036f394dd7 pinctrl: Enable device link creation for pin control
A pin controller may want to create a link between itself
and its clients to be sure of suspend/resume call ordering.

Introduce link_consumers field in pinctrl_desc structure to let
pinctrl core knows that controller expect to create a link.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
[Renamed create_link to link_consumers]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-05-23 09:34:54 +02:00
Yanjiang Jin
54a58185bf pinctrl: core: make sure strcmp() doesn't get a null parameter
Some drivers, for example, QCOM's qdf2xxx, set groups[gpio].name only
when gpio is valid, and leave invalid gpio names as null.
If we want to access the sys node "pinconf-groups",
pinctrl_get_group_selector() -> get_group_name() may return a null
pointer if group_selector is invalid, then the below Kernel panic
would happen since strcmp() uses this null pointer to do comparison.

 Unable to handle kernel NULL pointer dereference at ss 00000000
el:Internal error: Oops: 9600000[ 143.080279]
SMP
 CPU: 19 PID: 2493 Comm: read_all Tainted: G O
.aarch64 #1
 Hardware name: HXT Semiconductor HXT REP-2 System
 PC is at strcmp+0x18/0x154
 LR is at pinctrl_get_group_selector+0x6c/0xe8
 Process read_all (pid: 2493, stack limit =
 Call trace:
 Exception stack
  strcmp+0x18/0x154
  pin_config_group_get+0x64/0xd8
  pinconf_generic_dump_one+0xd8/0x1c0
  pinconf_generic_dump_pins+0x94/0xc8
  pinconf_groups_show+0xb4/0x104
  seq_read+0x178/0x464
  full_proxy_read+0x6c/0xac
  __vfs_read+0x58/0x178
  vfs_read+0x94/0x164
  SyS_read+0x60/0xc0
  __sys_trace_return+0x0/0x4
 --[ end trace]--
 Kernel panic - not syncing: Fatal exception

Signed-off-by: Yanjiang Jin <yanjiang.jin@hxt-semitech.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-01 13:46:13 +02:00
Tony Lindgren
a203728ac6 pinctrl: core: Return selector to the pinctrl driver
We must return the selector from pinctrl_generic_add_group() so
pin controller device drivers can remove the right group if needed
for deferred probe for example. And we now must make sure that a
proper name is passed so we can use it to check if the entry already
exists.

Note that fixes are also needed for the pin controller drivers to
use the selector value.

Fixes: c7059c5ac7 ("pinctrl: core: Add generic pinctrl functions
for managing groups")
Reported-by: H. Nikolaus Schaller <hns@goldelico.com>
Cc: Christ van Willegen <cvwillegen@gmail.com>
Cc: Haojian Zhuang <haojian.zhuang@linaro.org>
Cc: Jacopo Mondi <jacopo+renesas@jmondi.org>
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Tested-By: H. Nikolaus Schaller <hns@goldelico.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-17 10:48:25 +02:00
Linus Walleij
c969cb2f70 pinctrl: Cut unused sysfs includes
We simply don't use sysfs.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-06-18 07:56:05 +02:00
Richard Fitzgerald
8b1b2dc7b4 pinctrl: core: Add missing EXPORT on pinctrl_register_mappings
Systems that don't have devicetree need pinctrl_register_mappings.
It should be EXPORT_SYMBOL_GPL so that it can be called from
pinctrl drivers built as modules.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-02 11:05:35 +01:00
Andy Shevchenko
b5520891a3 pinctrl: Re-use DEFINE_SHOW_ATTRIBUTE() macro
...instead of open coding file operations followed by custom ->open()
callbacks per each attribute.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-02-22 15:36:03 +01:00
Jan Kundrát
1781af563a pinctrl: mcp23s08: spi: Fix duplicate pinctrl debugfs entries
This is a bit more involved because the pinctrl core so far always
assumed that one device (with a unique dev_name) only contains a single
pinctrl thing. This is not true for the mcp23s08 driver for chips
connected over SPI. They have a "logical address" which means that
several chips can share one physical CS signal.

A downside of this patch are some possibly ugly names for the debugfs
entries, such as "spi1.1-mcp23xxx-pinctrl.2", etc.

Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-02-12 10:47:24 +01:00
Florian Fainelli
981ed1bfbc pinctrl: Really force states during suspend/resume
In case a platform only defaults a "default" set of pins, but not a
"sleep" set of pins, and this particular platform suspends and resumes
in a way that the pin states are not preserved by the hardware, when we
resume, we would call pinctrl_single_resume() -> pinctrl_force_default()
-> pinctrl_select_state() and the first thing we do is check that the
pins state is the same as before, and do nothing.

In order to fix this, decouple the actual state change from
pinctrl_select_state() and move it pinctrl_commit_state(), while keeping
the p->state == state check in pinctrl_select_state() not to change the
caller assumptions. pinctrl_force_sleep() and pinctrl_force_default()
are updated to bypass the state check by calling pinctrl_commit_state().

[Linus Walleij]
The forced pin control states are currently only used in some pin
controller drivers that grab their own reference to their own pins.
This is equal to the pin control hogs: pins taken by pin control
devices since there are no corresponding device in the Linux device
hierarchy, such as memory controller lines or unused GPIO lines,
or GPIO lines that are used orthogonally from the GPIO subsystem
but pincontrol-wise managed as hogs (non-strict mode, allowing
simultaneous use by GPIO and pin control). For this case forcing
the state from the drivers' suspend()/resume() callbacks makes
sense and should semantically match the name of the function.

Fixes: 6e5e959dde ("pinctrl: API changes to support multiple states per device")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-12-20 08:24:13 +01:00
Linus Walleij
a9a1d2a782 pinctrl/gpio: Unify namespace for cross-calls
The pinctrl_request_gpio() and pinctrl_free_gpio() break the nice
namespacing in the other cross-calls like pinctrl_gpio_foo().
Just rename them and all references so we have one namespace
with all cross-calls under pinctrl_gpio_*().

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-22 11:02:10 +02:00
Markus Elfring
f68f848131 pinctrl: core: Delete an error message
Omit an extra message for a memory allocation failure in this function.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-08-31 15:44:16 +02:00
Masahiro Yamada
906a2a3955 pinctrl: add __rcu annotations to fix sparse warnings
Sparse reports "warning: incorrect type in assignment (different
address spaces)".

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-08-14 15:01:59 +02:00
Masahiro Yamada
3f713b7c22 pinctrl: move const qualifier before struct
Update subsystem wide for consistency.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-08-14 15:01:02 +02:00
Linus Walleij
6183061967 Linux 4.12-rc7
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Merge tag 'v4.12-rc7' into devel

Linux 4.12-rc7
2017-06-29 14:27:39 +02:00
Tony Lindgren
664b7c4728 pinctrl: core: Fix warning by removing bogus code
Andre Przywara <andre.przywara@arm.com> noticed that we can get the
following warning with -EPROBE_DEFER:

"WARNING: CPU: 1 PID: 89 at drivers/base/dd.c:349
driver_probe_device+0x2ac/0x2e8"

Let's fix the issue by removing the indices as suggested by
Tejun Heo <tj@kernel.org>. All we have to do here is kill the radix
tree.

I probably ended up with the indices after grepping for removal
of all entries using radix_tree_for_each_slot() and the first
match found was gmap_radix_tree_free(). Anyways, no need for
indices here, and we can just do remove all the entries using
radix_tree_for_each_slot() along how the item_kill_tree() test
case does.

Fixes: c7059c5ac7 ("pinctrl: core: Add generic pinctrl functions for managing groups")
Fixes: a76edc89b1 ("pinctrl: core: Add generic pinctrl functions for managing groups")
Reported-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-05-22 17:36:13 +02:00
Nikita Yushchenko
7f0ff06c1c pinctrl: When claiming hog, skip maps not served by same device
When pinctrl device registers, it automatically claims hogs, that is,
maps that pinctrl device serves for itself.

It is possible that in addition to SoC's pinctrl device, other pinctrl
devices get registered. E.g. some gpio expander devies are registered
as pinctrl devices. For such devices, pinctrl maps could be defined
that set up SoC's pins (e.g. interrupt pin for gpio expander). Such
a map will have target device set to gpio expander.

Here is device tree snippet that causes this scenario:

&i2c0 {
	sx1503@20 {
		compatible = "semtech,sx1503q";
		pinctrl-names = "default";
		pinctrl-0 = <&pinctrl_sx1503_20>;
		...
	};
};
...
&iomuxc {
	pinctrl_sx1503_20: pinctrl-sx1503-20 {
		fsl,pins = <
			VF610_PAD_PTB1__GPIO_23         0x219d
		>;
	};
};

Such a map will have target device set to gpio expander. However is not
a hog, it is a regular map that is claimed by core before gpio expander
device is probed.

Thus when looking for hogs, it is not enough to check that map's target
device is set to pinctrl device being registered. Need also check that
map's control device is also set to the same.

Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-05-22 17:05:44 +02:00
Markus Elfring
cea234e996 pinctrl: Adjust nine checks for null pointers
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The script “checkpatch.pl” pointed information out like the following.

Comparison to NULL could be written …

Thus fix the affected source code places.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-05-22 10:39:25 +02:00
Markus Elfring
390e10464d pinctrl: Use seq_putc() in pinctrl_maps_show()
A single character (line break) should be put into a sequence.
Thus use the corresponding function "seq_putc".

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-05-22 10:39:24 +02:00
Linus Torvalds
68fed41e0f This is the bulk of pin control changes for the v4.12 cycle:
Core changes:
 
 - Add bi-directional and output-enable pin configurations to
   the generic bindings and generic pin controlling core.
 
 New drivers or subdrivers:
 
 - Armada 37xx SoC pin controller and GPIO support.
 
 - Axis ARTPEC-6 SoC pin controller support.
 
 - AllWinner A64 R_PIO controller support, and opening up the
   AllWinner sunxi driver for ARM64 use.
 
 - Rockchip RK3328 support.
 
 - Renesas R-Car H3 ES2.0 support.
 
 - STM32F469 support in the STM32 driver.
 
 - Aspeed G4 and G5 pin controller support.
 
 Improvements:
 
 - A whole slew of realtime improvements to drivers implementing
   irqchips: BCM, AMD, SiRF, sunxi, rockchip.
 
 - Switch meson driver to get the GPIO ranges from the device
   tree.
 
 - Input schmitt trigger support on the Rockchip driver.
 
 - Enable the sunxi (AllWinner) driver to also be used on ARM64
   silicon.
 
 - Name the Qualcomm QDF2xxx GPIO lines.
 
 - Support GMMR GPIO regions on the Intel Cherryview. This
   fixes a serialization problem on these platforms.
 
 - Pad retention support for the Samsung Exynos 5433.
 
 - Handle suspend-to-ram in the AT91-pio4 driver.
 
 - Pin configuration support in the Aspeed driver.
 
 Cleanups:
 
 - The final name of Rockchip RK1108 was RV1108 so rename the
   driver and variables to stay consistent.
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Merge tag 'pinctrl-v4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl

Pull pin control updates from Linus Walleij:
 "This is the bulk of pin control changes for the v4.12 cycle.

  The extra week before the merge window actually resulted in some of
  the type of fixes that usually arrive after the merge window already
  starting to trickle in from eager developers using -next, I'm
  impressed.

  I have recruited a Samsung subsubsystem maintainer (Krzysztof) to deal
  with the onset of Samsung patches. It works great.

  Apart from that it is a boring round, just incremental updates and
  fixes all over the place, no serious core changes or anything exciting
  like that. The most pleasing to see is Julia Cartwrights work to audit
  the irqchip-providing drivers for realtime locking compliance. It's
  one of those "I should really get around to looking into that" things
  that have been on my TODO list since forever.

  Summary:

  Core changes:

   - add bi-directional and output-enable pin configurations to the
     generic bindings and generic pin controlling core.

  New drivers or subdrivers:

   - Armada 37xx SoC pin controller and GPIO support.

   - Axis ARTPEC-6 SoC pin controller support.

   - AllWinner A64 R_PIO controller support, and opening up the
     AllWinner sunxi driver for ARM64 use.

   - Rockchip RK3328 support.

   - Renesas R-Car H3 ES2.0 support.

   - STM32F469 support in the STM32 driver.

   - Aspeed G4 and G5 pin controller support.

  Improvements:

   - a whole slew of realtime improvements to drivers implementing
     irqchips: BCM, AMD, SiRF, sunxi, rockchip.

   - switch meson driver to get the GPIO ranges from the device tree.

   - input schmitt trigger support on the Rockchip driver.

   - enable the sunxi (AllWinner) driver to also be used on ARM64
     silicon.

   - name the Qualcomm QDF2xxx GPIO lines.

   - support GMMR GPIO regions on the Intel Cherryview. This fixes a
     serialization problem on these platforms.

   - pad retention support for the Samsung Exynos 5433.

   - handle suspend-to-ram in the AT91-pio4 driver.

   - pin configuration support in the Aspeed driver.

  Cleanups:

   - the final name of Rockchip RK1108 was RV1108 so rename the driver
     and variables to stay consistent"

* tag 'pinctrl-v4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (80 commits)
  pinctrl: mediatek: Add missing pinctrl bindings for mt7623
  pinctrl: artpec6: Fix return value check in artpec6_pmx_probe()
  pinctrl: artpec6: Remove .owner field for driver
  pinctrl: tegra: xusb: Silence sparse warnings
  ARM: at91/at91-pinctrl documentation: fix spelling mistake: "contoller" -> "controller"
  pinctrl: make artpec6 explicitly non-modular
  pinctrl: aspeed: g5: Add pinconf support
  pinctrl: aspeed: g4: Add pinconf support
  pinctrl: aspeed: Add core pinconf support
  pinctrl: aspeed: Document pinconf in devicetree bindings
  pinctrl: Add st,stm32f469-pinctrl compatible to stm32-pinctrl
  pinctrl: stm32: Add STM32F469 MCU support
  Documentation: dt: Remove ngpios from stm32-pinctrl binding
  pinctrl: stm32: replace device_initcall() with arch_initcall()
  pinctrl: stm32: add possibility to use gpio-ranges to declare bank range
  pinctrl: armada-37xx: Add gpio support
  pinctrl: armada-37xx: Add pin controller support for Armada 37xx
  pinctrl: dt-bindings: Add documentation for Armada 37xx pin controllers
  pinctrl: core: Make pinctrl_init_controller() static
  pinctrl: generic: Add bi-directional and output-enable
  ...
2017-05-02 17:59:33 -07:00
Andy Shevchenko
0ca4921fe9 pinctrl: core: Make pinctrl_init_controller() static
pinctrl_init_controller() is not used outside core.c, thus make it
static and prevent compiler to warn.

drivers/pinctrl/core.c:1943:21: warning: no previous prototype for ‘pinctrl_init_controller’ [-Wmissing-prototypes]
 struct pinctrl_dev *pinctrl_init_controller(struct pinctrl_desc *pctldesc,
                     ^~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-04-24 11:10:13 +02:00
Tony Lindgren
6118714275 pinctrl: core: Fix pinctrl_register_and_init() with pinctrl_enable()
Recent pinctrl changes to allow dynamic allocation of pins exposed one
more issue with the pinctrl pins claimed early by the controller itself.
This caused a regression for IMX6 pinctrl hogs.

Before enabling the pin controller driver we need to wait until it has
been properly initialized, then claim the hogs, and only then enable it.

To fix the regression, split the code into pinctrl_claim_hogs() and
pinctrl_enable(). And then let's require that pinctrl_enable() is always
called by the pin controller driver when ready after calling
pinctrl_register_and_init().

Depends-on: 950b0d91dc ("pinctrl: core: Fix regression caused by delayed
work for hogs")
Fixes: df61b366af26 ("pinctrl: core: Use delayed work for hogs")
Fixes: e566fc11ea ("pinctrl: imx: use generic pinctrl helpers for
managing groups")
Cc: Haojian Zhuang <haojian.zhuang@linaro.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mika Penttilä <mika.penttila@nextfour.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Nishanth Menon <nm@ti.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Stefan Agner <stefan@agner.ch>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Gary Bisson <gary.bisson@boundarydevices.com>
Tested-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-04-07 01:08:08 +02:00
Andy Shevchenko
3ec440e33f pinctrl: Fix spelling typos
Just fix spelling typos in comments.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-03-14 14:42:22 +01:00
Charles Keepax
50842cbd34 pinctrl: Fix trivial spelling typo in a comment
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-03-06 14:36:14 +01:00
Linus Walleij
27a2873617 Merge branch 'ib-pinctrl-genprops' into devel 2017-01-26 15:27:54 +01:00
Mika Westerberg
15381bc7c7 pinctrl: Allow configuration of pins from gpiolib based drivers
When a GPIO driver is backed by a pinctrl driver the GPIO driver
sometimes needs to call the pinctrl driver to configure certain things,
like whether the pin is used as input or output. In addition to this
there are other configurations applicable to GPIOs such as setting
debounce time of the GPIO.

To support this we introduce a new function pinctrl_gpio_set_config()
that can be used by gpiolib based driver to pass configuration requests
to the backing pinctrl driver.

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>
2017-01-26 15:23:01 +01:00
Thierry Reding
46daed6ebd pinctrl: Initialize pinctrl_dev.node
The struct pinctrl_dev's node field is not properly set up, which means
the .prev and .next fields will be NULL. That's not something that the
linked list code can deal with, so extra care must be taken when using
these fields. An example of this is introduced in commit 3429fb3cda
("pinctrl: Fix panic when pinctrl devices with hogs are unregistered")
where list_del() is made conditional on the pinctrl device being part
of the pinctrl device list. This is to ensure that list_del() won't
crash upon encountering a NULL pointer in .prev and/or .next.

After initializing the list head there's no need to jump through these
extra hoops and list_del() will work unconditionally. This is because
the initialized list head points to itself and therefore the .prev and
.next fields can be properly dereferenced.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-13 16:30:52 +01:00
Tony Lindgren
950b0d91dc pinctrl: core: Fix regression caused by delayed work for hogs
Commit df61b366af26 ("pinctrl: core: Use delayed work for hogs") caused a
regression at least with sh-pfc that is also a GPIO controller as
noted by Geert Uytterhoeven <geert@linux-m68k.org>.

As the original pinctrl_register() has issues calling pin controller
driver functions early before the controller has finished registering,
we can't just revert commit df61b366af26. That would break the drivers
using GENERIC_PINCTRL_GROUPS or GENERIC_PINMUX_FUNCTIONS.

So let's fix the issue with the following steps as a single patch:

1. Revert the late_init parts of commit df61b366af26.

   The late_init clearly won't work and we have to just give up
   on fixing pinctrl_register() for GENERIC_PINCTRL_GROUPS and
   GENERIC_PINMUX_FUNCTIONS.

2. Split pinctrl_register() into two parts

   By splitting pinctrl_register() into pinctrl_init_controller()
   and pinctrl_create_and_start() we have better control over when
   it's safe to call pinctrl_create().

3. Introduce a new pinctrl_register_and_init() function

   As suggested by Linus Walleij <linus.walleij@linaro.org>, we
   can just introduce a new function for the controllers that need
   pinctrl_create() called later.

4. Convert the four known problem cases to use new function

   Let's convert pinctrl-imx, pinctrl-single, sh-pfc and ti-iodelay
   to use the new function to fix the issues. The rest of the drivers
   can be converted later. Let's also update Documentation/pinctrl.txt
   accordingly because of the known issues with pinctrl_register().

Fixes: df61b366af26 ("pinctrl: core: Use delayed work for hogs")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Gary Bisson <gary.bisson@boundarydevices.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-13 16:25:17 +01:00
Bjorn Andersson
2104d12d11 pinctrl: Drop error prints on kzalloc() failure
Upon failing kzalloc() will print an error message in the log, so
there's no need for additional printouts. Also standardizes the "!ptr"
vs "ptr == NULL" while I'm touching those lines.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-11 14:29:29 +01:00
Tony Lindgren
92c2b67184 pinctrl: core: Make dt_free_map optional
If the pin controller driver is using devm_kzalloc, there may not be
anything to do for dt_free_map. Let's make it optional to avoid
unncessary boilerplate code.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-09 19:41:07 +01:00
Jon Hunter
3429fb3cda pinctrl: Fix panic when pinctrl devices with hogs are unregistered
Commit df61b366af26 ('pinctrl: core: Use delayed work for hogs')
deferred part of the registration for pinctrl devices if the pinctrl
device has hogs. This introduced a window where if the pinctrl device
with hogs was sucessfully registered, but then unregistered again
(which could be caused by parent device being probe deferred) before
the delayed work has chanced to run, then this will cause a kernel
panic to occur because:

1. The 'pctldev->p' has not yet been initialised and when unregistering
   the pinctrl device we only check to see if it is an error value, but
   now it could also be NULL.
2. The pinctrl device may not have been added to the 'pinctrldev_list'
   list and we don't check to see if it was added before removing.

Fix up the above by checking to see if the 'pctldev->p' pointer is an
error value or NULL before putting the pinctrl device and verifying
that the pinctrl device is present in 'pinctrldev_list' before removing.

Fixes: df61b366af26 ('pinctrl: core: Use delayed work for hogs')
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-05 17:14:44 +01:00
Tony Lindgren
a76edc89b1 pinctrl: core: Add generic pinctrl functions for managing groups
We can add generic helpers for function handling for cases where the pin
controller driver does not need to use static arrays.

Signed-off-by: Tony Lindgren <tony@atomide.com>
[Renamed the Kconfig item and moved things around]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-03 09:26:18 +01:00
Linus Walleij
c033a718f6 pinctrl: stricten up generic group code
Rename the symbol PINCTRL_GENERIC to PINCTRL_GENERIC_GROUPS since
it all pertains to groups. Replace everywhere.

ifdef out the radix tree and the struct when not using the
generic groups.

Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-03 09:26:18 +01:00
Tony Lindgren
c7059c5ac7 pinctrl: core: Add generic pinctrl functions for managing groups
We can add generic helpers for pin group handling for cases where the pin
controller driver does not need to use static arrays.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-03 09:26:17 +01:00
Linus Walleij
2d22e5b006 pinctrl: add some comments to the hog/late init code
It confused me a bit so it may confuse others. Make it crystal
clear what is going on here for any future readers.

Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-03 09:26:17 +01:00
Tony Lindgren
99e4f67508 pinctrl: core: Use delayed work for hogs
Having the pin control framework call pin controller functions
before it's probe has finished is not nice as the pin controller
device driver does not yet have struct pinctrl_dev handle.

Let's fix this issue by adding deferred work for late init. This is
needed to be able to add pinctrl generic helper functions that expect
to know struct pinctrl_dev handle. Note that we now need to call
create_pinctrl() directly as we don't want to add the pin controller
to the list of controllers until the hogs are claimed. We also need
to pass the pinctrl_dev to the device tree parser functions as they
otherwise won't find the right controller at this point.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-03 09:26:16 +01:00
Masahiro Yamada
cd8f61f1e5 pinctrl: copy per-pin driver private data to struct pin_desc
Currently, struct pinctrl_pin_desc can have per-pin driver private
data, but it is not copied to struct pin_desc.

For a driver with sparse pin space, for-loop search like below would
be necessary in order to get the driver-specific data for a desired
pin number.

  for (i = 0; i < pctldev->desc->npins; i++)
          if (pin_number == pctldev->desc->pins[i].number)
                  return pctldev->desc->pins[i].drv_data;

This is not efficient for a driver with a large number of pins.
So, copy the data to struct pin_desc when each pin is registered
for the faster radix tree lookup.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-31 10:27:19 +02:00
Masahiro Yamada
cf9d994dcf pinctrl: do not care about blank pin name
If a pin name is not specified in struct pinctrl_pin_desc,
pinctrl_register_one_pin() dynamically assigns its name.
So, desc->name is always a valid pointer here.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-31 10:19:56 +02:00
Laxman Dewangan
3024f920eb pinctrl: zynq: Use devm_pinctrl_register() for pinctrl registration
Use devm_pinctrl_register() for pin control registration and
remove the need of .remove callback.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Sören Brinkmann <soren.brinkmann@xilinx.com>
Cc: linux-gpio@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: Sören Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-21 09:23:27 +02:00
Laxman Dewangan
80e0f8d94d pinctrl: Add devm_ apis for pinctrl_{register, unregister}
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>
2016-04-21 00:01:21 +02:00
Joachim Eastwood
b18537cd8e pinctrl: core: create nolock version of pinctrl_find_gpio_range_from_pin
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>
2016-03-07 10:41:20 +07:00
Douglas Anderson
ef0eebc051 drivers/pinctrl: Add the concept of an "init" state
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>
2015-10-27 11:24:23 +01:00
Tony Lindgren
942cde7240 pinctrl: core: Warn about NULL gpio_chip in pinctrl_ready_for_gpio_range()
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>
2015-09-14 09:13:43 +02:00