summaryrefslogtreecommitdiff
path: root/drivers/pinctrl/Makefile
AgeCommit message (Collapse)Author
2012-07-14pinctrl: Add one-register-per-pin type device tree based pinctrl driverTony Lindgren
Add one-register-per-pin type device tree based pinctrl driver. This driver has been tested on omap2+ series of processors, where there is either an 8 or 16-bit padconf register for each pin. Support for other similar pinmux controllers can be added. Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-05-22Merge tag 'pinctrl' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-socLinus Torvalds
Pull arm soc-specific pinctrl changes from Olof Johansson: "With this, five platforms are moving to the relatively new pinctrl subsystem for their pin management, replacing the older soc specific in-kernel interfaces with common code. There is quite a bit of net addition of code for each platform being added to the pinctrl subsystem. But the payback comes later when adding new boards can be done by only providing new device trees instead." Fix up trivial conflicts in arch/arm/mach-ux500/{Makefile,board-mop500.c} * tag 'pinctrl' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (61 commits) mtd: nand: gpmi: fix compile error caused by pinctrl call ARM: PRIMA2: select PINCTRL and PINCTRL_SIRF in Kconfig ARM: nomadik: enable PINCTRL_NOMADIK where needed ARM: mxs: enable pinctrl support video: mxsfb: adopt pinctrl support ASoC: mxs-saif: adopt pinctrl support i2c: mxs: adopt pinctrl support mtd: nand: gpmi: adopt pinctrl support mmc: mxs-mmc: adopt pinctrl support serial: mxs-auart: adopt pinctrl support serial: amba-pl011: adopt pinctrl support spi/imx: adopt pinctrl support i2c: imx: adopt pinctrl support can: flexcan: adopt pinctrl support net: fec: adopt pinctrl support ARM: ux500: switch MSP to using pinctrl for pins ARM: ux500: alter MSP registration to return a device pointer ARM: ux500: switch to using pinctrl for uart0 ARM: ux500: delete custom pin control system ARM: ux500: switch over to Nomadik pinctrl driver ...
2012-05-20pinctrl: pinctrl-imx: add imx51 pinctrl driverDong Aisheng
ChangeLog v1->v2: * change PIN_FUNC_ID base in binding doc to 0 from 1. Acked-by: Shawn Guo <shawn.guo@linaro.org> 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>
2012-05-20pinctrl: pinctrl-imx: add imx53 pinctrl driverDong Aisheng
ChangeLog v1->v2: * change PIN_FUNC_ID base in binding doc to 0 from 1. Acked-by: Shawn Guo <shawn.guo@linaro.org> 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>
2012-05-12Merge tag 'ux500-gpio-pins-for-3.5' of ↵Olof Johansson
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-stericsson into next/pinctrl ux500 GPIO and pinctrl changes for kernel 3.5 * tag 'ux500-gpio-pins-for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-stericsson: ARM: ux500: switch MSP to using pinctrl for pins ARM: ux500: alter MSP registration to return a device pointer ARM: ux500: switch to using pinctrl for uart0 ARM: ux500: delete custom pin control system ARM: ux500: switch over to Nomadik pinctrl driver pinctrl: add sleep state definition pinctrl/nomadik: implement pin configuration pinctrl/nomadik: implement pin multiplexing pinctrl/nomadik: reuse GPIO debug function for pins pinctrl/nomadik: break out single GPIO debug function pinctrl/nomadik: basic Nomadik pinctrl interface pinctrl/nomadik: !CONFIG_OF build error gpio: move the Nomadik GPIO driver to pinctrl Context conflicts resolved in drivers/pinctrl/Kconfig and drivers/pinctrl/Makefile. Signed-off-by: Olof Johansson <olof@lixom.net>
2012-05-12Merge branches 'depends/pinctrl/devel' and 'depends/rmk/clkdev' into ↵Arnd Bergmann
spear/pinctrl The spear/pinctrl branch has hard dependencies on both the pinctrl branch and the clkdev branch. We merge those here to fix it up without having to rebase a branch that has been pulled into other stable branches already. Conflicts: Documentation/driver-model/devres.txt Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2012-05-11pinctrl/nomadik: basic Nomadik pinctrl interfaceLinus Walleij
This adds a scratch pin control interface to the Nomadik pinctrl driver, and defines the pins and groups in the DB8500 ASIC. We define GPIO ranges to cover the pins exposed. The DB8500 has more pins than this but we restrict the driver to the pins that can be controlled from the combined GPIO and pin control hardware to begin with. ChangeLog v1->v2: - Base on the latest pinctrl development from pinctrl-mergebase-20120418 so we can get rid of legacy group count mechanism. Also drop the range checks for group index, this is handled by the core now. Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-05-11gpio: move the Nomadik GPIO driver to pinctrlLinus Walleij
I'm moving this driver over to the pinctrl subsystem to convert the custom pin mux/config scheme over to use pinctrl. Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-05-02pinctrl: add pinctrl-mxs supportShawn Guo
Add pinctrl support for Freescale MXS SoCs, i.MX23 and i.MX28. The driver supports device tree probe only. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-05-02pinctrl: pinctrl-imx: add imx6q pinctrl driverDong Aisheng
Acked-by: Stephen Warren <swarren@wwwdotorg.org> Acked-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-05-02pinctrl: pinctrl-imx: add imx pinctrl core driverDong Aisheng
The driver has mux and config support while the gpio is still not supported. For select input setting, the driver will handle it internally and do not need user to take care of it. The pinctrl-imx core driver will parse the dts file and dynamically create the pinmux functions and groups. Each IMX SoC pinctrl driver should register pins with a pin register map including mux register and config register and select input map to core for proper operations. Acked-by: Stephen Warren <swarren@wwwdotorg.org> Acked-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-04-22pinctrl: Add SPEAr pinctrl driversViresh Kumar
This adds pinctrl driver for SPEAr platform. It also updates MAINTAINERS file for SPEAr pinctrl drivers. Signed-off-by: Viresh Kumar <viresh.kumar@st.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Stephen Warren <swarren@wwwdotorg.org>
2012-04-18pinctrl: fix build when CONFIG_OF && !CONFIG_PINCTRLStephen Warren
pinctrl/devicetree.c won't compile when !CONFIG_PINCTRL, since the pinctrl headers don't declare some types when !PINCTRL. Make sure pinctrl/Makefile only attempts to compile devicetree.c when OF && PINCTRL. 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>
2012-04-18pinctrl: 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>
2012-03-12pinctrl: introduce generic pin configLinus Walleij
This is a split-off from the earlier patch set which adds generic pin configuration for the pin controllers that want it. Since we may have a system with mixed generic and custom pin controllers, we pass a boolean in the pin controller ops vtable to indicate if it is generic. ChangeLog v1->v5: - Follow parent patch versioning number system. - Document the semantic meaning of return values from pin config get functions, so we can iterate over pins and check their properties from debugfs as part of the generic config code. - Use proper cast functions in the generic debugfs pin config file. - Expand generic config to optionally cover groups too. ChangeLog v5->v6: - Update to match underlying changes. ChangeLog v6->v7: - Drop DRIVE_OFF parameter, use bias high impedance for this - Delete argument for drive modes push-pull, od and os. These are now just state transitions. - Delete slew rate rising/falling due to discussions on on proper semantics - Drop config wakeup, struct irq_chip does this for now, add back if need be. - Set PIN_CONFIG_END to 0x7fff making room for custom config parameters from 0x8000 and up. - Prefix accessor functions with pinconf_
2012-03-06Merge branch 'pinctrl-tegra-for-next-diet' into for-nextLinus Walleij
2012-03-06pinctrl: add a driver for NVIDIA TegraStephen Warren
This adds a driver for the Tegra pinmux, and required parameterization data for Tegra20 and Tegra30. The driver is initially added with driver name and device tree compatible value that won't cause this driver to be used. A later change will switch the pinctrl driver to use the correct values, switch the old pinmux driver to be disabled, and update all code that uses the old pinmux APIs to use the new pinctrl APIs. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Olof Johansson <olof@lixom.net> [squashed "fix case of Tegra30's foo_groups[] arrays"] Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-01pinctrl: enable pinmux for mmp seriesHaojian Zhuang
Support PXA168/PXA910/MMP2 pinmux. Now only support function switch. Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com> [Rebase and fix some whitespace issues] Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-01-03pinctrl: rename U300 and SIRF pin controllersLinus Walleij
For stringent order, rename the pinmux-* pin controllers to pinctrl-* and also rename the Kconfig symbols and in-kernel users. Cc: Rongjun Ying <Rongjun.Ying@csr.com> Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Acked-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-01-03pinctrl: add a pin config interfaceLinus Walleij
This add per-pin and per-group pin config interfaces for biasing, driving and other such electronic properties. The details of passed configurations are passed in an opaque unsigned long which may be dereferences to integer types, structs or lists on either side of the configuration interface. ChangeLog v1->v2: - Clear split of terminology: we now have pin controllers, and those may support two interfaces using vtables: pin multiplexing and pin configuration. - Break out pin configuration to its own C file, controllers may implement only config without mux, and vice versa, so keep each sub-functionality of pin controllers separate. Introduce CONFIG_PINCONF in Kconfig. - Implement some core logic around pin configuration in the pinconf.c file. - Remove UNKNOWN config states, these were just surplus baggage. - Remove FLOAT config state - HIGH_IMPEDANCE should be enough for everyone. - PIN_CONFIG_POWER_SOURCE added to handle switching the power supply for the pin logic between different sources - Explicit DISABLE config enums to turn schmitt-trigger, wakeup etc OFF. - Update documentation to reflect all the recent reasoning. ChangeLog v2->v3: - Twist API around to pass around arrays of config tuples instead of (param, value) pairs everywhere. - Explicit drive strength semantics for push/pull and similar drive modes, this shall be the number of drive stages vs nominal load impedance, which should match the actual electronics used in push/pull CMOS or TTY totempoles. - Drop load capacitance configuration - I probably don't know what I'm doing here so leave it out. - Drop PIN_CONFIG_INPUT_SCHMITT_OFF, instead the argument zero to PIN_CONFIG_INPUT_SCHMITT turns schmitt trigger off. - Drop PIN_CONFIG_NORMAL_POWER_MODE and have a well defined argument to PIN_CONFIG_LOW_POWER_MODE to get out of it instead. - Drop PIN_CONFIG_WAKEUP_ENABLE/DISABLE and just use PIN_CONFIG_WAKEUP with defined value zero to turn wakeup off. - Add PIN_CONFIG_INPUT_DEBOUNCE for configuring debounce time on input lines. - Fix a bug when we tried to configure pins for pin controllers without pinconf support. - Initialized debugfs properly so it works. - Initialize the mutex properly and lock around config tampering sections. - Check the return value from get_initial_config() properly. ChangeLog v3->v4: - Export the pin_config_get(), pin_config_set() and pin_config_group() functions. - Drop the entire concept of just getting initial config and keeping track of pin states internally, instead ask the pins what state they are in. Previous idea was plain wrong, if the device cannot keep track of its state, the driver should do it. - Drop the generic configuration layout, it seems this impose too much restriction on some pin controllers, so let them do things the way they want and split off support for generic config as an optional add-on. ChangeLog v4->v5: - Introduce two symmetric driver calls for group configuration, .pin_config_group_[get|set] and corresponding external calls. - Remove generic semantic meanings of return values from config calls, these belong in the generic config patch. Just pass the return value through instead. - Add a debugfs entry "pinconf-groups" to read status from group configuration only, also slam in a per-group debug callback in the pinconf_ops so custom drivers can display something meaningful for their pins. - Fix some dangling newline. - Drop dangling #else clause. - Update documentation to match the above. ChangeLog v5->v6: - Change to using a pin name as parameter for the [get|set]_config() functions, as suggested by Stephen Warren. This is more natural as names will be what a developer has access to in written documentation etc. ChangeLog v6->v7: - Refactor out by-pin and by-name get/set functions, only expose the by-name functions externally, expose the by-pin functions internally. - Show supported pin control functionality in the debugfs pinctrl-devices file. Acked-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-01-03pinctrl: move the U300 GPIO driver to pinctrlLinus Walleij
This driver will be converted to a dual GPIO + pinctrl driver since it supports biasing and driving control options. Hopefully it can serve as an example. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2011-12-08pinctrl: make the "Debug PINCTRL calls" entry actually do somethingUwe Kleine-König
DEBUG_PINCTRL wasn't used at all and DEBUG_PINMUX doesn't exist. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2011-10-13pinctrl: add a driver for the CSR SiRFprimaII pinmuxRongjun Ying
This creates a pin controller driver for the SiRFprinaII pin mux portions. Signed-off-by: Rongjun Ying <Rongjun.Ying@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> [Fixup for changed function names and semantics in the v10 patch] Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
2011-10-13pinctrl: add a driver for the U300 pinmuxLinus Walleij
This adds a driver for the U300 pinmux portions of the system controller "SYSCON". It also serves as an example of how to use the pinmux subsystem. This driver also houses the platform data for the only supported platform. This deletes the old U300 driver in arch/arm/mach-u300 and replace it with a driver using the new subsystem. The new driver is considerably fatter than the old one, but it also registers all 467 pins of the system and adds the power and EMIF pin groups and corresponding functions. The idea is to use this driver as a a reference for other implementation so it needs to be as complete and verbose as possible. Reviewed-by: Barry Song <21cnbao@gmail.com> [Fixup for changed function names and semantics in the v10 patch] Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2011-10-13drivers: create a pin control subsystemLinus Walleij
This creates a subsystem for handling of pin control devices. These are devices that control different aspects of package pins. Currently it handles pinmuxing, i.e. assigning electronic functions to groups of pins on primarily PGA and BGA type of chip packages which are common in embedded systems. The plan is to also handle other I/O pin control aspects such as biasing, driving, input properties such as schmitt-triggering, load capacitance etc within this subsystem, to remove a lot of ARM arch code as well as feature-creepy GPIO drivers which are implementing the same thing over and over again. This is being done to depopulate the arch/arm/* directory of such custom drivers and try to abstract the infrastructure they all need. See the Documentation/pinctrl.txt file that is part of this patch for more details. ChangeLog v1->v2: - Various minor fixes from Joe's and Stephens review comments - Added a pinmux_config() that can invoke custom configuration with arbitrary data passed in or out to/from the pinmux driver ChangeLog v2->v3: - Renamed subsystem folder to "pinctrl" since we will likely want to keep other pin control such as biasing in this subsystem too, so let us keep to something generic even though we're mainly doing pinmux now. - As a consequence, register pins as an abstract entity separate from the pinmux. The muxing functions will claim pins out of the pin pool and make sure they do not collide. Pins can now be named by the pinctrl core. - Converted the pin lookup from a static array into a radix tree, I agreed with Grant Likely to try to avoid any static allocation (which is crap for device tree stuff) so I just rewrote this to be dynamic, just like irq number descriptors. The platform-wide definition of number of pins goes away - this is now just the sum total of the pins registered to the subsystem. - Make sure mappings with only a function name and no device works properly. ChangeLog v3->v4: - Define a number space per controller instead of globally, Stephen and Grant requested the same thing so now maps need to define target controller, and the radix tree of pin descriptors is a property on each pin controller device. - Add a compulsory pinctrl device entry to the pinctrl mapping table. This must match the pinctrl device, like "pinctrl.0" - Split the file core.c in two: core.c and pinmux.c where the latter carry all pinmux stuff, the core is for generic pin control, and use local headers to access functionality between files. It is now possible to implement a "blank" pin controller without pinmux capabilities. This split will make new additions like pindrive.c, pinbias.c etc possible for combined drivers and chunks of functionality which is a GoodThing(TM). - Rewrite the interaction with the GPIO subsystem - the pin controller descriptor now handles this by defining an offset into the GPIO numberspace for its handled pin range. This is used to look up the apropriate pin controller for a GPIO pin. Then that specific GPIO range is matched 1-1 for the target controller instance. - Fixed a number of review comments from Joe Perches. - Broke out a header file pinctrl.h for the core pin handling stuff that will be reused by other stuff than pinmux. - Fixed some erroneous EXPORT() stuff. - Remove mispatched U300 Kconfig and Makefile entries - Fixed a number of review comments from Stephen Warren, not all of them - still WIP. But I think the new mapping that will specify which function goes to which pin mux controller address 50% of your concerns (else beat me up). ChangeLog v4->v5: - Defined a "position" for each function, so the pin controller now tracks a function in a certain position, and the pinmux maps define what position you want the function in. (Feedback from Stephen Warren and Sascha Hauer). - Since we now need to request a combined function+position from the machine mapping table that connect mux settings to drivers, it was extended with a position field and a name field. The name field is now used if you e.g. need to switch between two mux map settings at runtime. - Switched from a class device to using struct bus_type for this subsystem. Verified sysfs functionality: seems to work fine. (Feedback from Arnd Bergmann and Greg Kroah-Hartman) - Define a per pincontroller list of GPIO ranges from the GPIO pin space that can be handled by the pin controller. These can be added one by one at runtime. (Feedback from Barry Song) - Expanded documentation of regulator_[get|enable|disable|put] semantics. - Fixed a number of review comments from Barry Song. (Thanks!) ChangeLog v5->v6: - Create an abstract pin group concept that can sort pins into named and enumerated groups no matter what the use of these groups may be, one possible usecase is a group of pins being muxed in or so. The intention is however to also use these groups for other pin control activities. - Make it compulsory for pinmux functions to associate with at least one group, so the abstract pin group concept is used to define the groups of pins affected by a pinmux function. The pinmux driver interface has been altered so as to enforce a function to list applicable groups per function. - Provide an optional .group entry in the pinmux machine map so the map can select beteween different available groups to be used with a certain function. - Consequent changes all over the place so that e.g. debugfs present reasonable information about the world. - Drop the per-pin mux (*config) function in the pinmux_ops struct - I was afraid that this would start to be used for things totally unrelated to muxing, we can introduce that to the generic struct pinctrl_ops if needed. I want to keep muxing orthogonal to other pin control subjects and not mix these things up. ChangeLog v6->v7: - Make it possible to have several map entries matching the same device, pin controller and function, but using a different group, and alter the semantics so that pinmux_get() will pick all matching map entries, and store the associated groups in a list. The list will then be iterated over at pinmux_enable()/pinmux_disable() and corresponding driver functions called for each defined group. Notice that you're only allowed to map multiple *groups* to the same { device, pin controller, function } triplet, attempts to map the same device to multiple pin controllers will for example fail. This is hopefully the crucial feature requested by Stephen Warren. - Add a pinmux hogging field to the pinmux mapping entries, and enable the pinmux core to hog pinmux map entries. This currently only works for pinmuxes without assigned devices as it looks now, but with device trees we can look up the corresponding struct device * entries when we register the pinmux driver, and have it hog each pinmux map in turn, for a simple approach to non-dynamic pin muxing. This addresses an issue from Grant Likely that the machine should take care of as much of the pinmux setup as possible, not the devices. By supplying a list of hogs, it can now instruct the core to take care of any static mappings. - Switch pinmux group retrieveal function to grab an array of strings representing the groups rather than an array of unsigned and rewrite accordingly. - Alter debugfs to show the grouplist handled by each pinmux. Also add a list of hogs. - Dynamically allocate a struct pinmux at pinmux_get() and free it at pinmux_put(), then add these to the global list of pinmuxes active as we go along. - Go over the list of pinmux maps at pinmux_get() time and repeatedly apply matches. - Retrieve applicable groups per function from the driver as a string array rather than a unsigned array, then lookup the enumerators. - Make the device to pinmux map a singleton - only allow the mapping table to be registered once and even tag the registration function with __init so it surely won't be abused. - Create a separate debugfs file to view the pinmux map at runtime. - Introduce a spin lock to the pin descriptor struct, lock it when modifying pin status entries. Reported by Stijn Devriendt. - Fix up the documentation after review from Stephen Warren. - Let the GPIO ranges give names as const char * instead of some fixed-length string. - add a function to unregister GPIO ranges to mirror the registration function. - Privatized the struct pinctrl_device and removed it from the <linux/pinctrl/pinctrl.h> API, the drivers do not need to know the members of this struct. It is now in the local header "core.h". - Rename the concept of "anonymous" mux maps to "system" muxes and add convenience macros and documentation. ChangeLog v7->v8: - Delete the leftover pinmux_config() function from the <linux/pinctrl/pinmux.h> header. - Fix a race condition found by Stijn Devriendt in pin_request() ChangeLog v8->v9: - Drop the bus_type and the sysfs attributes and all, we're not on the clear about how this should be used for e.g. userspace interfaces so let us save this for the future. - Use the right name in MAINTAINERS, PIN CONTROL rather than PINMUX - Don't kfree() the device state holder, let the .remove() callback handle this. - Fix up numerous kerneldoc headers to have one line for the function description and more verbose documentation below the parameters ChangeLog v9->v10: - pinctrl: EXPORT_SYMBOL needs export.h, folded in a patch from Steven Rothwell - fix pinctrl_register error handling, folded in a patch from Axel Lin - Various fixes to documentation text so that it's consistent. - Removed pointless comment from drivers/Kconfig - Removed dependency on SYSFS since we removed the bus in v9. - Renamed hopelessly abbreviated pctldev_* functions to the more verbose pinctrl_dev_* - Drop mutex properly when looking up GPIO ranges - Return NULL instead of ERR_PTR() errors on registration of pin controllers, using cast pointers is fragile. We can live without the detailed error codes for sure. Cc: Stijn Devriendt <highguy@gmail.com> Cc: Joe Perches <joe@perches.com> Cc: Russell King <linux@arm.linux.org.uk> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Stephen Warren <swarren@nvidia.com> Tested-by: Barry Song <21cnbao@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>