Commit Graph

125 Commits

Author SHA1 Message Date
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
Masahiro Yamada 2b38ca6d1a pinctrl: use dev_err() to show message in pinctrl_register_one_pin()
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>
2015-07-27 14:43:43 +02:00
Linus Torvalds 93a4b1b946 Here is the bulk of pin control changes for the v4.2 series:
- 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
  ...
2015-06-24 19:21:02 -07:00
Masahiro Yamada 323de9efdf pinctrl: make pinctrl_register() return proper error code
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>
2015-06-10 14:49:52 +02:00
Masahiro Yamada 7e9236ff3d pinctrl: fix confusing debug message in pinctrl_register_map()
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>
2015-06-02 13:32:20 +02:00
Geert Uytterhoeven b217e4385d pinctrl: Grammar s/used in as/used as/
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12 13:17:41 +02:00
Doug Anderson c5272a2856 pinctrl: Don't just pretend to protect pinctrl_maps, do it for real
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>
2015-05-06 16:24:28 +02:00
Jim Lin db93facfb0 pinctrl: Fix two deadlocks
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>
2015-01-14 14:20:33 +01:00
Fan Wu 2243a87d90 pinctrl: avoid duplicated calling enable_pinmux_setting for a pin
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>
2014-07-11 14:08:26 +02:00
Antoine Ténart e5b3b2d9ed pinctrl: allows not to define the get_group_pins operation
When using a group only pinctrl driver, which does not have any
information on the pins it is useless to define a get_group_pins
always returning an empty list of pins.

When not using get_group_pin[1], a driver must implement it so
pins = NULL and num_pins = 0. This patch makes it the default
behaviour if not defined in the pinctrl driver when used in
pinmux enable and disable funtions and in pinctrl_groups_show.

It also adds a check in pinctrl_get_group_pins and return -EINVAL if
not defined. This function is called in the gpiolib when adding when
pingroup range. It cannot be used if no group is defined, so this seams
reasonable.

[1] get_group_pin(struct pinctrl_dev *pctldev,
		  unsigned selector,
		  const unsigned **pins,
		  unsigned *num_pins);

Signed-off-by: Antoine Ténart <antoine.tenart@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-04-22 14:47:02 +02:00
Florian Vaussard e7f2a44489 pinctrl: do not init debugfs entries for unimplemented functionalities
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>
2014-02-06 13:48:17 +01:00
Stanislaw Gruszka 7b320cb1ed pinctrl: protect pinctrl_list add
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>
2014-02-04 21:59:45 +01:00
Christian Ruppert 586a87e6ed pinctrl/gpio: non-linear GPIO ranges accesible from gpiolib
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>
2013-10-16 15:33:50 +02:00
Linus Walleij 6ad30ce046 Linux 3.11-rc7
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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
2013-08-29 09:46:30 +02:00
Axel Lin 9b77ace409 pinctrl: core: Add proper mutex lock in pinctrl_request_gpio
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>
2013-08-28 13:13:05 +02:00
Axel Lin 6c325f874c pinctrl: core: Remove unnecessary test for desc->name
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>
2013-08-23 08:56:29 +02:00
Axel Lin 5ffbe2e613 pinctrl: core: Hold pctldev->mutex mutex lock while traversing gpio_ranges list
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>
2013-08-23 08:56:28 +02:00
Axel Lin f005902108 pinctrl: core: Hold pinctrldev_list_mutex mutex while traversing pinctrldev_list
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>
2013-08-23 08:56:27 +02:00
Linus Walleij db6c2c69c2 pinctrl: fix a memleak when freeing maps
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>
2013-07-25 17:18:36 +02:00
Tony Lindgren f33334978a pinctrl: Remove duplicate code in pinctrl_pm_select_state functions
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>
2013-07-23 01:23:27 +02:00
Sachin Kamat 843aec9653 pinctrl: Staticize local symbols
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>
2013-06-18 16:54:45 +02:00
Wei Yongjun c8f50e8657 pinctrl: core: fix missing unlock on error in pinctrl_find_gpio_range_from_pin()
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>
2013-06-18 09:41:15 +02:00
Arnd Bergmann f472deadd5 pinctrl: export pinctrl_pm_select_*_state
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>
2013-06-17 18:29:32 +02:00
Christian Ruppert c8587eeef8 pinctrl: add pin list based GPIO ranges
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>
2013-06-17 18:18:28 +02:00
Linus Walleij 14005ee270 drivers: pinctrl sleep and idle states in the core
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>
2013-06-16 11:56:52 +02:00
Linus Walleij 44d5f7bbea pinctrl: sink pinctrldev_list_mutex
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>
2013-06-16 11:56:50 +02:00
Daniel Mack d463f82d22 pinctrl: fix mutex deadlock in get_pinctrl_dev_from_of_node()
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>
2013-04-30 13:02:04 +02:00
Patrice Chotard 42fed7ba44 pinctrl: move subsystem mutex to pinctrl_dev struct
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>
2013-04-26 17:01:35 +02:00
Richard Genoud 385d94246b pinctrl: simplify the re-enable old state code in pinctrl_select_state
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>
2013-04-03 14:38:27 +02:00
Richard Genoud af60617771 pinctrl: select_state: don't call pinctrl_free_setting on error
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>
2013-04-03 14:36:43 +02:00
Richard Genoud 175ca83c0b pinctrl: pinctrl_select_state: set the old_state back on error
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>
2013-04-03 14:27:31 +02:00
Richard Genoud 8009d5ff00 pinctrl: remove superfluous optimization in pinctrl_select_state_locked
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>
2013-04-03 14:22:39 +02:00