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path: root/drivers/pinctrl/core.c
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2016-03-07pinctrl: core: create nolock version of pinctrl_find_gpio_range_from_pinJoachim Eastwood
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>
2015-10-27drivers/pinctrl: Add the concept of an "init" stateDouglas Anderson
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>
2015-09-14pinctrl: core: Warn about NULL gpio_chip in pinctrl_ready_for_gpio_range()Tony Lindgren
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>
2015-07-27pinctrl: use dev_err() to show message in pinctrl_register_one_pin()Masahiro Yamada
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>
2015-06-24Merge tag 'pinctrl-v4.2-1' of ↵Linus Torvalds
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 ...
2015-06-10pinctrl: make pinctrl_register() return proper error codeMasahiro Yamada
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>
2015-06-02pinctrl: fix confusing debug message in pinctrl_register_map()Masahiro Yamada
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>
2015-05-12pinctrl: Grammar s/used in as/used as/Geert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-06pinctrl: Don't just pretend to protect pinctrl_maps, do it for realDoug Anderson
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: 42fed7ba44e4 ("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>
2015-01-14pinctrl: Fix two deadlocksJim Lin
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>
2014-07-11pinctrl: avoid duplicated calling enable_pinmux_setting for a pinFan Wu
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>
2014-04-22pinctrl: allows not to define the get_group_pins operationAntoine Ténart
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>
2014-02-06pinctrl: do not init debugfs entries for unimplemented functionalitiesFlorian Vaussard
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>
2014-02-04pinctrl: protect pinctrl_list addStanislaw Gruszka
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: 42fed7ba44e ("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>
2013-10-16pinctrl/gpio: non-linear GPIO ranges accesible from gpiolibChristian Ruppert
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>
2013-08-29Merge tag 'v3.11-rc7' into develLinus Walleij
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
2013-08-28pinctrl: core: Add proper mutex lock in pinctrl_request_gpioAxel Lin
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>
2013-08-23pinctrl: core: Remove unnecessary test for desc->nameAxel Lin
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>
2013-08-23pinctrl: core: Hold pctldev->mutex mutex lock while traversing gpio_ranges listAxel Lin
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>
2013-08-23pinctrl: core: Hold pinctrldev_list_mutex mutex while traversing pinctrldev_listAxel Lin
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>
2013-07-25pinctrl: fix a memleak when freeing mapsLinus Walleij
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>
2013-07-23pinctrl: Remove duplicate code in pinctrl_pm_select_state functionsTony Lindgren
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>
2013-06-18pinctrl: Staticize local symbolsSachin Kamat
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>
2013-06-18pinctrl: core: fix missing unlock on error in pinctrl_find_gpio_range_from_pin()Wei Yongjun
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>
2013-06-17pinctrl: export pinctrl_pm_select_*_stateArnd Bergmann
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>
2013-06-17pinctrl: add pin list based GPIO rangesChristian Ruppert
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>
2013-06-16drivers: pinctrl sleep and idle states in the coreLinus Walleij
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>
2013-06-16pinctrl: sink pinctrldev_list_mutexLinus Walleij
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>
2013-04-30pinctrl: fix mutex deadlock in get_pinctrl_dev_from_of_node()Daniel Mack
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>
2013-04-26pinctrl: move subsystem mutex to pinctrl_dev structPatrice Chotard
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>
2013-04-03pinctrl: simplify the re-enable old state code in pinctrl_select_stateRichard Genoud
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>
2013-04-03pinctrl: select_state: don't call pinctrl_free_setting on errorRichard Genoud
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>
2013-04-03pinctrl: pinctrl_select_state: set the old_state back on errorRichard Genoud
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>
2013-04-03pinctrl: remove superfluous optimization in pinctrl_select_state_lockedRichard Genoud
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>
2013-04-03pinctrl: use dev_info instead of pr_info in pinctrl_select_state_lockedRichard Genoud
And remove superfluous brackets. 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>
2013-04-03pinctrl: core: add dependence of GPIOLIBHaojian Zhuang
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>
2013-03-27pinctrl: re-enable old state in case of error in pinctrl_select_stateRichard Genoud
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>
2013-03-27pinctrl: disable and free setting in select_state in case of errorRichard Genoud
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>
2013-03-27pinctrl: create pinctrl_free_setting functionRichard Genoud
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>
2013-03-07pinctrl: check pinctrl ready for gpio rangeHaojian Zhuang
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>
2013-03-07pinctrl: core: use devres_release() instead of devres_destroy()Jingoo Han
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>
2013-02-10pinctrl/pinconfig: add debug interfaceLaurent Meunier
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>
2013-01-30pinctrl: core: Make pinctrl_release staticSachin Kamat
'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>
2013-01-23drivers/pinctrl: grab default handles from device coreLinus Walleij
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>
2013-01-21pinctrl: core: get devname from pinctrl_devHaojian Zhuang
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>
2013-01-11pinctrl: add sleep mode management for hogsJulien Delacou
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>
2013-01-11pinctrl: skip deferral of hogsLinus Walleij
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>
2012-12-26pinctrl: fix comment mistakeLinus Walleij
This variable pertains to pinctrl handles not muxes specifically. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-21pinctrl: add function to retrieve range from pinLinus Walleij
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>
2012-11-21pinctrl: make range registration defer properlyLinus Walleij
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>