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path: root/drivers/pinctrl/pinmux.c
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2018-01-16pinctrl: pinmux: Use seq_putc() in pinmux_pins_show()Markus Elfring
A single character (line break) should be put into a sequence. Thus use the corresponding function "seq_putc". This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-01-09pinctrl: remove redundant mux_setting clear in pinmux_disable_setting()Masahiro Yamada
desc->mux_setting is set to NULL in pin_free() called just below. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-08-14pinctrl: add __rcu annotations to fix sparse warningsMasahiro Yamada
Sparse reports "warning: incorrect type in assignment (different address spaces)". Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-08-14pinctrl: move const qualifier before structMasahiro Yamada
Update subsystem wide for consistency. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-05-22pinctrl: core: Fix warning by removing bogus codeTony Lindgren
Andre Przywara <andre.przywara@arm.com> noticed that we can get the following warning with -EPROBE_DEFER: "WARNING: CPU: 1 PID: 89 at drivers/base/dd.c:349 driver_probe_device+0x2ac/0x2e8" Let's fix the issue by removing the indices as suggested by Tejun Heo <tj@kernel.org>. All we have to do here is kill the radix tree. I probably ended up with the indices after grepping for removal of all entries using radix_tree_for_each_slot() and the first match found was gmap_radix_tree_free(). Anyways, no need for indices here, and we can just do remove all the entries using radix_tree_for_each_slot() along how the item_kill_tree() test case does. Fixes: c7059c5ac70a ("pinctrl: core: Add generic pinctrl functions for managing groups") Fixes: a76edc89b100 ("pinctrl: core: Add generic pinctrl functions for managing groups") Reported-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Tested-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-04-07pinctrl: pinmux: Fix kerneldoc for pinmux_generic_add_function()Geert Uytterhoeven
Correct the incorrect function name and description. Fixes: a76edc89b100e4fe ("pinctrl: core: Add generic pinctrl functions for managing groups") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-03pinctrl: core: Add generic pinctrl functions for managing groupsTony Lindgren
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>
2016-12-30pinctrl: simplify check for pin request conflictsVladimir Zapolskiy
This is a non-functional change, which deletes code duplication in two of four if-if branches by reordering the checks. Functional identity of the code change can be shown by running through the whole truth table of boolean arguments. Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-31pinctrl: return -ENOMEM instead of -EINVAL for kasprintf() failureMasahiro Yamada
-ENOMEM is more suitable error code because kasprintf() fails in case of memory shortage. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-31pinctrl: do not care about blank pin nameMasahiro Yamada
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>
2016-03-17pinctrl: convert to use match_string() helperAndy Shevchenko
The new helper returns index of the mathing string in an array. We would use it here. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-14pinctrl: join lines that can be a single line within 80 columnsMasahiro Yamada
There is no reason to break a line shorter than 80 columns. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-07-27pinctrl: use dev_err() to show message in pinmux_func_name_to_selector()Masahiro Yamada
Use dev_err() rather than pr_err() to display the error message. pinctrl_dev_get_name(pctldev) is no longer necessary 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>
2015-06-10pinctrl: don't print unavailable function groupsLudovic Desroches
There is no reason to try to print groups associated to a function if get_function_groups returns an error. Moreover, it can lead to a NULL pointer dereference error. Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-28pinctrl: improve debugfs for strict controllersLinus Walleij
If we know we are using a strict pin controller (one that cannot mix device functions+group use and GPIO) we can be a bit more specific in debugfs, just print either device-function-group or GPIO consumer for the pin. Let's do that to be helpful. Cc: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-06pinctrl: move strict option to pinmux_opsLinus Walleij
While the pinmux_ops are ideally just a vtable for pin mux calls, the "strict" setting belongs so intuitively with the pin multiplexing that we should move it here anyway. Putting it in the top pinctrl_desc makes no sense. Cc: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-06pinctrl: allow exlusive GPIO/mux pin allocationSonic Zhang
Disallow simultaneous use of the the GPIO and peripheral mux functions by setting a flag "strict" in struct pinctrl_desc. The blackfin pinmux and gpio controller doesn't allow user to set up a pin for both GPIO and peripheral function. So, add flag strict in struct pinctrl_desc to check both gpio_owner and mux_owner before approving the pin request. v2-changes: - if strict flag is set, check gpio_owner and mux_onwer in if and else clause v3-changes: - add kerneldoc for this struct - augment Documentation/pinctrl.txt Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-09-04pinctrl: clean up after enable refactoringLinus Walleij
commit 2243a87d90b42eb38bc281957df3e57c712b5e56 "pinctrl: avoid duplicated calling enable_pinmux_setting for a pin" removed the .disable callback from the struct pinmux_ops, making the .enable() callback the only remaining callback. However .enable() is a bad name as it seems to imply that a muxing can also be disabled. Rename the callback to .set_mux() and also take this opportunity to clean out any remaining mentions of .disable() from the documentation. Acked-by: Stephen Warren <swarren@nvidia.com> Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com> Acked-by: Fan Wu <fwu@marvell.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>
2013-11-04pinctrl: remove minor dead codeMichael Opdenacker
This removes a test whether the 'desc' variable is NULL. This possibility has already been eliminated by the below test earlier in the loop: if (desc == NULL) { dev_warn(pctldev->dev, "could not get pin desc for pin %d\n", pins[i]); continue; } Found with Coverity: CID #1090078 Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-08-14pinctrl: improve warning messagesLinus Walleij
Print out the affected group name on activation of pin mux settings, and warn if you cannot free a pin that should have been part of a certain setting. ChangeLog v1->v2: - Also print the pin name in the error messages. Cc: Sonic Zhang <sonic.zhang@analog.com> Reviewed-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-08-14pinctrl: pinmux: Don't free pins requested by other devices in ↵Sonic Zhang
pinmux_disable_setting. One peripheral may share part of its pins with the 2nd peripheral and the other pins with the 3rd. If it requests all pins when part of them has already be requested and owned by the 2nd peripheral, this request fails and pinmux_disable_setting() is called. The pinmux_disable_setting() frees all pins of the first peripheral without checking if the pin is owned by itself or the 2nd, which results in the malfunction of the 2nd peripheral driver. Signed-off-by: Sonic Zhang <sonic.zhang@analog.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>
2013-03-21pinmux: forbid mux_usecount to be set at UINT_MAXRichard Genoud
If pin_free is called on a pin already freed, mux_usecount is set to UINT_MAX which is really a bad idea. This will issue a warning, so that we can correct the code responsible for the double free. 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>
2012-11-11pinctrl: pinmux: Release all taken pins in pinmux_enable_setting error pathsAxel Lin
Currently pinmux_enable_setting does not release all taken pins if ops->enable() returns error. This patch ensures all taken pins are released in any error paths. Signed-off-by: Axel Lin <axel.lin@ingics.com> 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>
2012-09-14pinctrl: use kasprintf() in pinmux_request_gpio()Thomas Petazzoni
Instead of using a temporary buffer, snprintf() and kstrdup(), just use kasprintf() that does the same thing in just oneline. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Acked-by: Colin Cross <ccross@google.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-05-15pinctrl: make pinmux disable function optionalDong Aisheng
Some SoCs may not have pinmux disable function in HW. 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>
2012-05-07pinctrl: add more info to error msgs in pin_requestStephen Warren
Additionally print which pin the request failed for, which entity already claimed it, and what entity was trying to claim it. Remove duplicate device name from a debug message. Clean up some indentation. Signed-off-by: Stephen Warren <swarren@nvidia.com> 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>
2012-04-24pinctrl: fix signed vs unsigned conditionals inside pinmux_map_to_settingJohn Crispin
pinmux_map_to_setting() uses setting->data.mux.func/group to store the return code of pinmux_func_name_to_selector/pinctrl_get_group_selector(). However, struct pinctrl_setting_mux defines these elements as unsigned, resulting in all error codes getting lost. The conditionals following the assignments will always evaluate to false thus breaking the error paths. This bug can be triggered by loading a pinmux group map from the devicetree with an invalid function/group string. Signed-off-by: John Crispin <blogic@openwrt.org> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-04-18pinctrl: show pin name when request pinsDong Aisheng
Pin name is more useful to users. 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: add some error checking for user interfacesDong Aisheng
This patch can avoid kernel oops in case the mux or config function is not supported by driver. 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: fix pinmux_check_ops error checkingDong Aisheng
Do not use get_functions_count before checking. 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: 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>
2012-03-12pinctrl: allow concurrent gpio and mux function ownership of pinsStephen Warren
Per recent updates to Documentation/gpio.txt, gpiolib drivers should inform pinctrl when a GPIO is requested. pinctrl then marks that pin as in-use for that GPIO function. When an SoC muxes pins in a group, it's quite possible for the group to contain e.g. 6 pins, but only 4 of them actually be needed by the HW module that's mux'd to them. In this case, the other 2 pins could be used as GPIOs. However, pinctrl marks all the pins within the group as in-use by the selected mux function. To allow the expected gpiolib interaction, separate the concepts of pin ownership into two parts: One for the mux function and one for GPIO usage. Finally, allow those two ownerships to exist in parallel. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-03-05pinctrl: Show selected function and group in pinmux-pins debugfsStephen Warren
Until recently, the pinctrl pinmux-pins debugfs file displayed the selected function for each owned pin. This feature was removed during restructing in support of recent API rework. This change restoreds this feature, and also displays the group that the function was selected on, in case a pin is a member of multiple groups. Based on work by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Stephen Warren <swarren@nvidia.com> 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: add usecount to pins for muxingStephen Warren
Multiple mapping table entries could reference the same pin, and hence "own" it. This would be unusual now that pinctrl_get() represents a single state for a client device, but in the future when it represents all known states for a device, this is quite likely. Implement reference counting for pin ownership to handle 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>
2012-03-05pinctrl: 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: enhance pinctrl_get() to handle multiple functionsStephen Warren
At present, pinctrl_get() assumes that all matching mapping table entries have the same "function" value, albeit potentially applied to different pins/groups. This change removes this restriction; pinctrl_get() can now handle a set of mapping tables where different functions are applied to the various pins/groups. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-29pinctrl: make the pinmux-pins more helpfulLinus Walleij
The debugfs file pinmux-pins used to tell which function was enabled but now states simply which device owns the pin. Being owned by the pinctrl driver itself means just that it's hogged so be a bit more helpful by printing that. ChangeLog v1->v2: - Preserve the self-referential owner field, just clarify that when the pin controller states itself as owner this means that it's hogged. Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Acked-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>
2012-02-22pinctrl: record a pin owner, not mux function, when requesting pinsStephen Warren
When pins are requested/acquired/got, some device becomes the owner of their mux setting. At this point, it isn't certain which mux function will be selected for the pin, since this may vary between each of the device's states in the pinctrl mapping table. As such, we should record the owning device, not what we think the initial mux setting will be, when requesting pins. This doesn't make a lot of difference right now since pinctrl_get gets only one single device/state combination, but this will make a difference when pinctrl_get gets all states, and pinctrl_select_state can switch between states. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-22pinctrl: Re-order pinmux.[ch] to match each-otherStephen Warren
Modify the two files so that the order of function prototypes in the header matches the order of implementations in the .c file. 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>
2012-02-10pinctrl: factor pin control handles over to the coreLinus Walleij
This moves the per-devices struct pinctrl handles and device map over from the pinmux part of the subsystem to the core pinctrl part. This makes the device handles core infrastructure with the goal of using these handles also for pin configuration, so that device drivers (or boards etc) will need one and only one handle to the pin control core. Acked-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-10pinctrl: move generic functions to the pinctrl_ namespaceLinus Walleij
Since we want to use the former pinmux handles and mapping tables for generic control involving both muxing and configuration we begin refactoring by renaming them from pinmux_* to pinctrl_*. ChangeLog v1->v2: - Also rename the PINMUX_* macros in machine.h to PIN_ as indicated in the documentation so as to reflect the generic nature of these mapping entries from now on. Acked-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>