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path: root/drivers/pinctrl/core.c
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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>
2012-11-21gpiolib: rename find_pinctrl_*Linus Walleij
Rename the function find_pinctrl_and_add_gpio_range() to pinctrl_find_and_add_gpio_range() so as to be consistent with the rest of the functions. Reviewed-by: Stephen Warren <swarren@nvidia.com> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-11gpiolib: provide provision to register pin rangesShiraz Hashim
pinctrl subsystem needs gpio chip base to prepare set of gpio pin ranges, which a given pinctrl driver can handle. This is important to handle pinctrl gpio request calls in order to program a given pin properly for gpio operation. As gpio base is allocated dynamically during gpiochip registration, presently there exists no clean way to pass this information to the pinctrl subsystem. After few discussions from [1], it was concluded that may be gpio controller reporting the pin range it supports, is a better way than pinctrl subsystem directly registering it. [1] http://comments.gmane.org/gmane.linux.ports.arm.kernel/184816 Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com> [Edited documentation a bit] Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-11Revert "pinctrl: remove pinctrl_remove_gpio_range"Viresh Kumar
This reverts earlier commit which removed pinctrl_remove_gpio_range(), because at that time there weren't any more users of that routine. It was removed as the removal of ranges was done in unregister of pinctrl. But as we are now registering stuff from gpiolib, we may remove and insert a gpio module multiple times. So, we need this routine again. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-11pinctrl: reserve pins when states are activatedLinus Walleij
This switches the way that pins are reserved for multiplexing: We used to do this when the map was parsed, at the creation of the settings inside the pinctrl handle, in pinmux_map_to_setting(). However this does not work for us, because we want to use the same set of pins with different devices at different times: the current code assumes that the pin groups in a pinmux state will only be used with one single device, albeit different groups can be active at different times. For example if a single I2C driver block is used to drive two different busses located on two pin groups A and B, then the pins for all possible states of a function are reserved when fetching the pinctrl handle: the I2C bus can choose either set A or set B by a mux state at runtime, but all pins in both group A and B (the superset) are effectively reserved for that I2C function and mapped to the device. Another device can never get in and use the pins in group A, even if the device/function is using group B at the moment. Instead: let use reserve the pins when the state is activated and drop them when the state is disabled, i.e. when we move to another state. This way different devices/functions can use the same pins at different times. We know that this is an odd way of doing things, but we really need to switch e.g. an SD-card slot to become a tracing output sink at runtime: we plug in a special "tracing card" then mux the pins that used to be an SD slot around to the tracing unit and push out tracing data there instead of SD-card traffic. As a side effect pinmux_free_setting() is unused but the stubs are kept for future additions of code. Cc: Patrice Chotard <patrice.chotard@st.com> Cc: Loic Pallardy <loic.pallardy@st.com> Acked-by: Stephen Warren <swarren@nvidia.com> Tested-by: Jean Nicolas Graux <jean-nicolas.graux@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-10-23pinctrl: fix missing unlock on error in pinctrl_groups_show()Wei Yongjun
Add the missing unlock on the error handle path in function pinctrl_groups_show(). Cc: stable@kernel.org Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-09-27pinctrl: Fix potential memory leak in pinctrl_register_one_pin()Sachin Kamat
'pindesc' was not freed when returning from an error induced exit path. Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-08-17trivial: pinctrl core: remove extraneous code linesRichard Genoud
In function pinctrl_get_locked, pointer p is returned on error, and also return on no_error. So, we just return it with no error test. It's pretty the same in function pinctrl_lookup_state_locked: state is returned in every case, so we drop the error test and just return state. Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
2012-07-03pinctrl: add pinctrl_add_gpio_ranges functionDong Aisheng
Often GPIO ranges are added in batch, so create a special function for that. Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-07-03pinctrl: remove pinctrl_remove_gpio_rangeDong Aisheng
The gpio ranges will be automatically removed when the pinctrl driver is unregistered. Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-07-03pinctrl/pinctrl-core: cleanup pinctrl_registerDevendra Naga
lots of places the ret is used just for non zero cases with out that also we can check the status of the function calls. Signed-off-by: Devendra Naga <devendra.aaru@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-06-04pinctrl: fix a minor harmless typoGuennadi Liakhovetski
The way the for_each_maps() macro is currently used, using "i" instead of "_i_" works and is harmless. Still, this is a bug, that can trigger any time, if the code around that macro changes. Better fix it now. Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-05-02pinctrl: support gpio request deferred probingDong Aisheng
As pinctrl handles, it may be possible the pinctrl gpio ranges are still not got registered when user call pinctrl_gpio_request. Thus, add defer support for it too. Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-04-26pinctrl: add pinctrl_provide_dummies interface for platforms to useDong Aisheng
Add a interface pinctrl_provide_dummies for platform to indicate whether it needs use pinctrl dummy state. ChangeLog v3->v4: * remove dummy gpio support in pinctrl subsystem. Let gpio driver decide whether it wants to use pinctrl gpio mux function. ChangeLog v2->v3: * Also changed the missed pinctrl gpio APIs in v1. ChangeLog v1->v2: * Based on sascha's suggestion, drop using kconfig since it will hide pinctrl errors on all other boards. See: https://lkml.org/lkml/2012/4/18/282 It seemed both Linus and Stephen agreed with this way, so i'm ok with it too. * Add dummy gpio support. pinctrl gpio in the same situation as state. * Patch name changed. Original is pinctrl: handle dummy state in core. * Split removing old dt dummy interface into a separate patch Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-04-26pinctrl: enhance reporting of errors when loading from DTJohn Crispin
There are a few places in the api where the code simply returns -EINVAL when it finds an error. An example is pinmux_map_to_setting() which now reports an error if we try to match a group with a function that it does not support. The reporting of errors in pinconf_check_ops and pinmux_check_ops now has the same style and is located inside the according functions and not the calling code. When the map is found in the DT but the default state can not be selected we get an error to know that the code at least tried. The patch also removes a stray word from one comment and a "->" from another for the sake of consistency. Finally we replace a few pr_err/debug() calls with dev_err/dbg(). Thanks go to Stephen Warren for reviewing the patch and enhancing the reporting inside pinmux_map_to_setting(). Signed-off-by: John Crispin <blogic@openwrt.org> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-04-26pinctrl: propagate map validation errorsStephen Warren
pinctrl_register_map() was returning early if pinmux_validate_map() or pinconf_validate_map() failed, but was not actually returning the error code. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-04-18pinctrl: show pin name for pingroups in sysfsDong Aisheng
Pin name is more useful to users. After change, when cat pingroups in sysfs, it becomes: root@freescale /sys/kernel/debug/pinctrl/20e0000.iomuxc$ cat pingroups registered pin groups: group: uart4grp-1 pin 219 (MX6Q_PAD_KEY_ROW0) pin 218 (MX6Q_PAD_KEY_COL0) group: usdhc4grp-1 pin 305 (MX6Q_PAD_SD4_CMD) pin 306 (MX6Q_PAD_SD4_CLK) pin 315 (MX6Q_PAD_SD4_DAT0) pin 316 (MX6Q_PAD_SD4_DAT1) pin 317 (MX6Q_PAD_SD4_DAT2) pin 318 (MX6Q_PAD_SD4_DAT3) pin 319 (MX6Q_PAD_SD4_DAT4) pin 320 (MX6Q_PAD_SD4_DAT5) pin 321 (MX6Q_PAD_SD4_DAT6) pin 322 (MX6Q_PAD_SD4_DAT7) Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-04-18pinctrl: implement devm_pinctrl_get()/put()Stephen Warren
These functions allow the driver core to automatically clean up any allocations made by drivers, thus leading to simplified drivers. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-04-18pinctrl: implement pinctrl deferred probingLinus Walleij
If drivers try to obtain pinctrl handles for a pin controller that has not yet registered to the subsystem, we need to be able to back out and retry with deferred probing. So let's return -EPROBE_DEFER whenever this location fails. Also downgrade the errors to info, maybe we will even set them to debug once the deferred probing is commonplace. Cc: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-04-18pinctrl: replace list_*() with get_*_count()Viresh Kumar
Most of the SoC drivers implement list_groups() and list_functions() routines for pinctrl and pinmux. These routines continue returning zero until the selector argument is greater than total count of available groups or functions. This patch replaces these list_*() routines with get_*_count() routines, which returns the number of available selection for SoC driver. pinctrl layer will use this value to check the range it can choose. This patch fixes all user drivers for this change. There are other routines in user drivers, which have checks to check validity of selector passed to them. It is also no more required and hence removed. Documentation updated as well. Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Viresh Kumar <viresh.kumar@st.com> [Folded in fix and fixed a minor merge artifact manually] Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-04-18pinctrl: core device tree mapping table parsing supportStephen Warren
During pinctrl_get(), if the client device has a device tree node, look for the common pinctrl properties there. If found, parse the referenced device tree nodes, with the help of the pinctrl drivers, and generate mapping table entries from them. During pinctrl_put(), free any results of device tree parsing. Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-04-18pinctrl: implement pinctrl_check_opsStephen Warren
Most code assumes that the pinctrl ops are present. Validate this when registering a pinctrl driver. Remove the one place in the code that was checking whether one of these non-optional ops was present. Signed-off-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-03-05pinctrl: enhance mapping table to support pin config operationsStephen Warren
The pinctrl mapping table can now contain entries to: * Set the mux function of a pin group * Apply a set of pin config options to a pin or a group This allows pinctrl_select_state() to apply pin configs settings as well as mux settings. v3: Fix find_pinctrl() to iterate over the correct list. s/_MUX_CONFIGS_/_CONFIGS_/ in mapping table macros. Fix documentation to use correct mapping table macro. v2: Added numerous extra PIN_MAP_*() special-case macros. Fixed kerneldoc typo. Delete pinctrl_get_pin_id() and replace it with pin_get_from_name(). Various minor fixes. Updates due to rebase. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-03-05pinctrl: API changes to support multiple states per deviceStephen Warren
The API model is changed from: p = pinctrl_get(dev, "state1"); pinctrl_enable(p); ... pinctrl_disable(p); pinctrl_put(p); p = pinctrl_get(dev, "state2"); pinctrl_enable(p); ... pinctrl_disable(p); pinctrl_put(p); to this: p = pinctrl_get(dev); s1 = pinctrl_lookup_state(p, "state1"); s2 = pinctrl_lookup_state(p, "state2"); pinctrl_select_state(p, s1); ... pinctrl_select_state(p, s2); ... pinctrl_put(p); This allows devices to directly transition between states without disabling the pin controller programming and put()/get()ing the configuration data each time. This model will also better suit pinconf programming, which doesn't have a concept of "disable". The special-case hogging feature of pin controllers is re-written to use the regular APIs instead of special-case code. Hence, the pinmux-hogs debugfs file is removed; see the top-level pinctrl-handles files for equivalent data. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-03-05pinctrl: refactor struct pinctrl handling in core.c vs pinmux.cStephen Warren
This change separates two aspects of struct pinctrl: a) The data representation of the parsed mapping table, into: 1) The top-level struct pinctrl object, a single entity returned by pinctrl_get(). 2) The parsed version of each mapping table entry, struct pinctrl_setting, of which there is one per mapping table entry. b) The code that handles this; the code for (1) above is in core.c, and the code to parse/execute each entry in (2) above is in pinmux.c, while the iteration over multiple settings is lifted to core.c. This will allow the following future changes: 1) pinctrl_get() API rework, so that struct pinctrl represents all states for the device, and the device can select between them without calling put()/get() again. 2) To support that, a struct pinctrl_state object will be inserted into the data model between the struct pinctrl and struct pinctrl_setting. 3) The mapping table will be extended to allow specification of pin config settings too. To support this, struct pinctrl_setting will be enhanced to store either mux settings or config settings, and functions will be added to pinconf.c to parse/execute pin configuration settings. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-03-05pinctrl: fix and simplify lockingStephen Warren
There are many problems with the current pinctrl locking: struct pinctrl_dev's gpio_ranges_lock isn't effective; pinctrl_match_gpio_range() only holds this lock while searching for a gpio range, but the found range is return and manipulated after releading the lock. This could allow pinctrl_remove_gpio_range() for that range while it is in use, and the caller may very well delete the range after removing it, causing pinctrl code to touch the now-free range object. Solving this requires the introduction of a higher-level lock, at least a lock per pin controller, which both gpio range registration and pinctrl_get()/put() will acquire. There is missing locking on HW programming; pin controllers may pack the configuration for different pins/groups/config options/... into one register, and hence have to read-modify-write the register. This needs to be protected, but currently isn't. Related, a future change will add a "complete" op to the pin controller drivers, the idea being that each state's programming will be programmed into the pinctrl driver followed by the "complete" call, which may e.g. flush a register cache to HW. For this to work, it must not be possible to interleave the pinctrl driver calls for different devices. As above, solving this requires the introduction of a higher-level lock, at least a lock per pin controller, which will be held for the duration of any pinctrl_enable()/disable() call. However, each pinctrl mapping table entry may affect a different pin controller if necessary. Hence, with a per-pin-controller lock, almost any pinctrl API may need to acquire multiple locks, one per controller. To avoid deadlock, these would need to be acquired in the same order in all cases. This is extremely difficult to implement in the case of pinctrl_get(), which doesn't know which pin controllers to lock until it has parsed the entire mapping table, since it contains somewhat arbitrary data. The simplest solution here is to introduce a single lock that covers all pin controllers at once. This will be acquired by all pinctrl APIs. This then makes struct pinctrl's mutex irrelevant, since that single lock will always be held whenever this mutex is currently held. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-03-02pinctrl: assume map table entries can't have a NULL name fieldStephen Warren
pinctrl_register_mappings() already requires that every mapping table entry have a non-NULL name field. Logically, this makes sense too; drivers should always request a specific named state so they know what they're getting. Relying on getting the first mentioned state in the mapping table is error-prone, and a nasty special case to implement, given that a given the mapping table may define multiple states for a device. Remove a small part of the documentation that talked about optionally requesting a specific state; it's mandatory now. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-03-02pinctrl: introduce PINCTRL_STATE_DEFAULT, define hogs as that stateStephen Warren
This provides a single centralized name for the default state. Update PIN_MAP_* macros to use this state name, instead of requiring the user to pass a state name in. With this change, hog entries in the mapping table are defined as those with state name PINCTRL_STATE_DEFAULT, i.e. all entries have the same name. This interacts badly with the nested iteration over mapping table entries in pinctrl_hog_maps() and pinctrl_hog_map() which would now attempt to claim each hog mapping table entry multiple times. Replacing the custom hog code with a simple pinctrl_get()/pinctrl_enable(). Update documentation and mapping tables to use this. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-29pinctrl: move pinctrl-maps debugfs file to top-levelStephen Warren
The debugfs file pinctrl-maps is a system-wide file, not specific to any pin controller, so place it in the top-level directory. Also, move the code implementing the file to keep the order of all the functions matching the order they're created in pinctrl_init_*debugfs(). The only non-obvious change here is no private data is passed to debugfs_create_file() or single_open(). Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-24pinctrl: remove pin and hogs locks from struct pinctrl_devStephen Warren
struct pinctrl_dev's pin_desc_tree_lock and pinctrl_hogs_lock aren't useful; the data they protect is read-only except when registering or unregistering a pinctrl_dev, and at those times, it doesn't make sense to protect one part of the structure independently from the rest. Move pinctrl_init_device_debugfs() to the end of pinctrl_register() so that debugfs can't access the struct pinctrl_dev until it's fully initialized, i.e. after the hogs are set up. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-24pinctrl: allocate sizeof(*p) instead of sizeof(struct foo)Stephen Warren
This hopefully makes it harder to take the sizeof the wrong type. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-24pinctrl: use dev_*() instead of pr_*(), add some msgs, minor cleanupsStephen Warren
e.g. dev_err instead of pr_err prints messages in a slightly more standardized format. Also, add a few more error messages to track down errors. Also, some small cleanups of messages. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-24pinctrl: disallow map table entries with NULL dev_name fieldStephen Warren
Hog entries are mapping table entries with .ctrl_dev_name == .dev_name. All other mapping table entries need .dev_name set so that they will match some pinctrl_get() call. All extant PIN_MAP*() macros set .dev_name. So, there is no reason to allow mapping table entries without .dev_name set. Update the code and documentation to disallow this. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-22pinctrl: error if mapping table's control dev can't be foundStephen Warren
This is a serious error, and the pin control system will not function correctly if it ends up not programing the mapping table entries into the HW. Instead of just ignoring this, error out. Signed-off-by: Stephen Warren <swarren@nvidia.com> [rebased to fit the applied patch series, cast error to pointer] Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-22pinctrl: downgrade pinctrl_get warning when no maps are foundStephen Warren
This may be perfectly legitimate. An IP block may get re-used across SoCs. Not all of those SoCs may need pinmux settings for the IP block, e.g. if one SoC dedicates pins to that function but another doesn't. The driver won't know this, and will always attempt to set up the pinmux. The mapping table defines whether any HW programming is actually needed. Acked-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Stephen Warren <swarren@nvidia.com> [rebased to fit the applied patch series] Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-22pinctrl: assume map table entries can't have a NULL ctrl_dev_name fieldStephen Warren
These are already disallowed. Clean up some code that doesn't assume this. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-22pinctrl: core.c/h cleanupsStephen Warren
* Make all functions internal to core.c static. Remove any of these from core.h. * Add any missing EXPORT_SYMBOL_GPL(). Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-22pinctrl: Store mapping table as a list of chunksStephen Warren
Instead of storing a single array of mapping table entries, which requires realloc()ing that array each time it's extended and copying the new data, simply store a list of pointers to the individual chunks. This also removes the need to copy the mapping table at all; a pointer is maintained to the original table, this saving memory. A macro for_each_maps() is introduced to hide the additional complexity of iterating over the map entries. This change will also simplify removing chunks of entries from the mapping table. This isn't important right now, but will be in the future, when mapping table entries are dynamically added when parsing them from the device tree, and removed when drivers no longer need to interact with pinctrl. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-22pinctrl: use list_add_tail instead of list_addStephen Warren
This mostly makes debugfs files print things in the order that they were added or acquired, which just feels a little more consistent. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-22pinctrl: pinctrl_register_mappings() shouldn't be __initStephen Warren
It may be common for pinctrl_register_mappings() to be used from __init context, but there's no reason that additional mappings shouldn't be added at a later point, e.g. if loading modules that add pin controllers and their mapping tables. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-22pinctrl: make "hog" mapping table entries workStephen Warren
Commit 77a5988 "pinctrl: changes hog mechanism to be self-referential" modified the way "hog" entries were represented in the mapping table. However, the new representation failed some error checks in pinctrl_hog_map(). Remove the now-bogus error-check, and fix the code to solve the issue the error-check used to avoid. Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-10pinctrl: changes hog mechanism to be self-referentialLinus Walleij
Instead of a specific boolean field to indicate if a map entry shall be hogged, treat self-reference as an indication of desired hogging. This drops one field off the map struct and has a nice Douglas R. Hofstadter-feel to it. Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Acked-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>