1
linux/drivers/pinctrl/Kconfig

622 lines
17 KiB
Plaintext
Raw Normal View History

# SPDX-License-Identifier: GPL-2.0-only
drivers: create a pin control subsystem 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>
2011-05-02 11:50:54 -07:00
#
# PINCTRL infrastructure and drivers
#
menuconfig PINCTRL
bool "Pin controllers"
drivers: create a pin control subsystem 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>
2011-05-02 11:50:54 -07:00
if PINCTRL
config GENERIC_PINCTRL_GROUPS
bool
drivers: create a pin control subsystem 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>
2011-05-02 11:50:54 -07:00
config PINMUX
bool "Support pin multiplexing controllers" if COMPILE_TEST
pinctrl: add a pin config interface 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>
2011-10-19 09:14:33 -07:00
config GENERIC_PINMUX_FUNCTIONS
bool
select PINMUX
pinctrl: add a pin config interface 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>
2011-10-19 09:14:33 -07:00
config PINCONF
bool "Support pin configuration controllers" if COMPILE_TEST
drivers: create a pin control subsystem 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>
2011-05-02 11:50:54 -07:00
config GENERIC_PINCONF
bool
select PINCONF
drivers: create a pin control subsystem 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>
2011-05-02 11:50:54 -07:00
config DEBUG_PINCTRL
bool "Debug PINCTRL calls"
depends on DEBUG_KERNEL
help
Say Y here to add some extra checks and diagnostics to PINCTRL calls.
config PINCTRL_AMD
bool "AMD GPIO pin control"
depends on HAS_IOMEM
depends on ACPI || COMPILE_TEST
select GPIOLIB
select GPIOLIB_IRQCHIP
select PINMUX
select PINCONF
select GENERIC_PINCONF
help
The driver for memory mapped GPIO functionality on AMD platforms
(x86 or arm). Most of the pins are usually muxed to some other
functionality by firmware, so only a small amount is available
for GPIO use.
Requires ACPI/FDT device enumeration code to set up a platform
device.
config PINCTRL_APPLE_GPIO
tristate "Apple SoC GPIO pin controller driver"
depends on ARCH_APPLE
select PINMUX
select GPIOLIB
select GPIOLIB_IRQCHIP
select GENERIC_PINCTRL_GROUPS
select GENERIC_PINMUX_FUNCTIONS
select OF_GPIO
help
This is the driver for the GPIO controller found on Apple ARM SoCs,
including M1.
This driver can also be built as a module. If so, the module
will be called pinctrl-apple-gpio.
config PINCTRL_ARTPEC6
bool "Axis ARTPEC-6 pin controller driver"
depends on MACH_ARTPEC6
select PINMUX
select GENERIC_PINCONF
help
This is the driver for the Axis ARTPEC-6 pin controller. This driver
supports pin function multiplexing as well as pin bias and drive
strength configuration. Device tree integration instructions can be
found in Documentation/devicetree/bindings/pinctrl/axis,artpec6-pinctrl.txt
config PINCTRL_AS3722
tristate "Pinctrl and GPIO driver for ams AS3722 PMIC"
depends on MFD_AS3722 && GPIOLIB
select PINMUX
select GENERIC_PINCONF
help
AS3722 device supports the configuration of GPIO pins for different
functionality. This driver supports the pinmux, push-pull and
open drain configuration for the GPIO pins of AS3722 devices. It also
supports the GPIO functionality through gpiolib.
config PINCTRL_AT91
bool "AT91 pinctrl driver"
depends on OF
depends on ARCH_AT91
select PINMUX
select PINCONF
select GPIOLIB
select OF_GPIO
select GPIOLIB_IRQCHIP
help
Say Y here to enable the at91 pinctrl driver
config PINCTRL_AT91PIO4
bool "AT91 PIO4 pinctrl driver"
depends on OF
depends on HAS_IOMEM
depends on ARCH_AT91 || COMPILE_TEST
select PINMUX
select GENERIC_PINCONF
select GPIOLIB
select GPIOLIB_IRQCHIP
select OF_GPIO
help
Say Y here to enable the at91 pinctrl/gpio driver for Atmel PIO4
controller available on sama5d2 SoC.
config PINCTRL_AXP209
tristate "X-Powers AXP209 PMIC pinctrl and GPIO Support"
depends on MFD_AXP20X
depends on OF
select PINMUX
select GENERIC_PINCONF
select GPIOLIB
help
AXP PMICs provides multiple GPIOs that can be muxed for different
functions. This driver bundles a pinctrl driver to select the function
muxing and a GPIO driver to handle the GPIO when the GPIO function is
selected.
Say Y to enable pinctrl and GPIO support for the AXP209 PMIC.
config PINCTRL_AW9523
tristate "Awinic AW9523/AW9523B I2C GPIO expander pinctrl driver"
depends on OF && I2C
select PINMUX
select PINCONF
select GENERIC_PINCONF
select GPIOLIB
select GPIOLIB_IRQCHIP
select REGMAP
select REGMAP_I2C
help
The Awinic AW9523/AW9523B is a multi-function I2C GPIO
expander with PWM functionality. This driver bundles a
pinctrl driver to select the function muxing and a GPIO
driver to handle GPIO, when the GPIO function is selected.
Say yes to enable pinctrl and GPIO support for the AW9523(B).
config PINCTRL_BM1880
bool "Bitmain BM1880 Pinctrl driver"
depends on OF && (ARCH_BITMAIN || COMPILE_TEST)
default ARCH_BITMAIN
select PINMUX
help
Pinctrl driver for Bitmain BM1880 SoC.
config PINCTRL_CY8C95X0
tristate "Cypress CY8C95X0 I2C pinctrl and GPIO driver"
depends on I2C
select GPIOLIB
select GPIOLIB_IRQCHIP
select PINMUX
select PINCONF
select GENERIC_PINCONF
select REGMAP_I2C
help
Support for 20/40/60 pin Cypress Cy8C95x0 pinctrl/gpio I2C expander.
This driver can also be built as a module. If so, the module will be
called pinctrl-cy8c95x0.
config PINCTRL_DA850_PUPD
tristate "TI DA850/OMAP-L138/AM18XX pull-up and pull-down groups"
depends on OF && (ARCH_DAVINCI_DA850 || COMPILE_TEST)
select PINCONF
select GENERIC_PINCONF
help
Driver for TI DA850/OMAP-L138/AM18XX pinconf. Used to control
pull-up and pull-down pin groups.
config PINCTRL_DA9062
tristate "Dialog Semiconductor DA9062 PMIC pinctrl and GPIO Support"
depends on MFD_DA9062
select GPIOLIB
help
The Dialog DA9062 PMIC provides multiple GPIOs that can be muxed for
different functions. This driver bundles a pinctrl driver to select the
function muxing and a GPIO driver to handle the GPIO when the GPIO
function is selected.
Say Y to enable pinctrl and GPIO support for the DA9062 PMIC.
config PINCTRL_DIGICOLOR
bool
depends on ARCH_DIGICOLOR || COMPILE_TEST
select PINMUX
select GENERIC_PINCONF
config PINCTRL_EP93XX
bool
depends on ARCH_EP93XX || COMPILE_TEST
select PINMUX
select GENERIC_PINCONF
select MFD_SYSCON
config PINCTRL_EQUILIBRIUM
tristate "Generic pinctrl and GPIO driver for Intel Lightning Mountain SoC"
depends on OF && HAS_IOMEM
depends on X86 || COMPILE_TEST
select PINMUX
select PINCONF
select GPIOLIB
select GPIO_GENERIC
select GPIOLIB_IRQCHIP
select GENERIC_PINCONF
select GENERIC_PINCTRL_GROUPS
select GENERIC_PINMUX_FUNCTIONS
help
Equilibrium driver is a pinctrl and GPIO driver for Intel Lightning
Mountain network processor SoC that supports both the GPIO and pin
control frameworks. It provides interfaces to setup pin muxing, assign
desired pin functions, configure GPIO attributes for LGM SoC pins.
Pin muxing and pin config settings are retrieved from device tree.
config PINCTRL_EYEQ5
bool "Mobileye EyeQ5 pinctrl driver"
depends on OF
depends on MACH_EYEQ5 || COMPILE_TEST
select PINMUX
select GENERIC_PINCONF
select AUXILIARY_BUS
default MACH_EYEQ5
help
Pin controller driver for the Mobileye EyeQ5 platform. It does both
pin config & pin muxing. It does not handle GPIO.
Pin muxing supports two functions for each pin: first is GPIO, second
is pin-dependent. Pin config is about bias & drive strength.
config PINCTRL_GEMINI
bool
depends on ARCH_GEMINI
default ARCH_GEMINI
select PINMUX
select GENERIC_PINCONF
select MFD_SYSCON
config PINCTRL_INGENIC
bool "Pinctrl driver for the Ingenic JZ47xx SoCs"
default MACH_INGENIC
depends on OF
depends on MIPS || COMPILE_TEST
select GENERIC_PINCONF
select GENERIC_PINCTRL_GROUPS
select GENERIC_PINMUX_FUNCTIONS
select GPIOLIB
select GPIOLIB_IRQCHIP
select REGMAP_MMIO
config PINCTRL_K210
bool "Pinctrl driver for the Canaan Kendryte K210 SoC"
depends on RISCV && SOC_CANAAN_K210 && OF
select GENERIC_PINMUX_FUNCTIONS
select GENERIC_PINCONF
select GPIOLIB
select OF_GPIO
select REGMAP_MMIO
default SOC_CANAAN_K210
help
Add support for the Canaan Kendryte K210 RISC-V SOC Field
Programmable IO Array (FPIOA) controller.
config PINCTRL_KEEMBAY
tristate "Pinctrl driver for Intel Keem Bay SoC"
depends on ARCH_KEEMBAY || (ARM64 && COMPILE_TEST)
depends on HAS_IOMEM
select PINMUX
select PINCONF
select GENERIC_PINCONF
select GENERIC_PINCTRL_GROUPS
select GENERIC_PINMUX_FUNCTIONS
select GPIOLIB
select GPIOLIB_IRQCHIP
select GPIO_GENERIC
help
This selects pin control driver for the Intel Keem Bay SoC.
It provides pin config functions such as pull-up, pull-down,
interrupt, drive strength, sec lock, Schmitt trigger, slew
rate control and direction control. This module will be
called as pinctrl-keembay.
config PINCTRL_LANTIQ
bool
depends on LANTIQ
select PINMUX
select PINCONF
config PINCTRL_FALCON
bool
depends on SOC_FALCON
depends on PINCTRL_LANTIQ
config PINCTRL_LOONGSON2
tristate "Pinctrl driver for the Loongson-2 SoC"
depends on OF && (LOONGARCH || COMPILE_TEST)
select PINMUX
select GENERIC_PINCONF
help
This selects pin control driver for the Loongson-2 SoC. It
provides pin config functions multiplexing. GPIO pin pull-up,
pull-down functions are not supported. Say yes to enable
pinctrl for Loongson-2 SoC.
config PINCTRL_XWAY
bool
depends on SOC_TYPE_XWAY
depends on PINCTRL_LANTIQ
config PINCTRL_LPC18XX
bool "NXP LPC18XX/43XX SCU pinctrl driver"
depends on OF && (ARCH_LPC18XX || COMPILE_TEST)
default ARCH_LPC18XX
select PINMUX
select GENERIC_PINCONF
help
Pinctrl driver for NXP LPC18xx/43xx System Control Unit (SCU).
config PINCTRL_MAX77620
tristate "MAX77620/MAX20024 Pincontrol support"
depends on MFD_MAX77620 && OF
select PINMUX
select GENERIC_PINCONF
help
Say Y here to enable Pin control support for Maxim MAX77620 PMIC.
This PMIC has 8 GPIO pins that work as GPIO as well as special
function in alternate mode. This driver also configure push-pull,
open drain, FPS slots etc.
config PINCTRL_MCP23S08_I2C
tristate
select REGMAP_I2C
config PINCTRL_MCP23S08_SPI
tristate
select REGMAP_SPI
config PINCTRL_MCP23S08
tristate "Microchip MCP23xxx I/O expander"
depends on SPI_MASTER || I2C
select GPIOLIB
select GPIOLIB_IRQCHIP
select GENERIC_PINCONF
select PINCTRL_MCP23S08_I2C if I2C
select PINCTRL_MCP23S08_SPI if SPI_MASTER
help
SPI/I2C driver for Microchip MCP23S08 / MCP23S17 / MCP23S18 /
MCP23008 / MCP23017 / MCP23018 I/O expanders.
This provides a GPIO interface supporting inputs and outputs and a
corresponding interrupt-controller.
config PINCTRL_MICROCHIP_SGPIO
tristate "Pinctrl driver for Microsemi/Microchip Serial GPIO"
depends on OF
depends on HAS_IOMEM
select GPIOLIB
select GPIOLIB_IRQCHIP
select GENERIC_PINCONF
select GENERIC_PINCTRL_GROUPS
select GENERIC_PINMUX_FUNCTIONS
select OF_GPIO
help
Support for the serial GPIO interface used on Microsemi and
Microchip SoCs. By using a serial interface, the SIO
controller significantly extends the number of available
GPIOs with a minimum number of additional pins on the
device. The primary purpose of the SIO controller is to
connect control signals from SFP modules and to act as an
LED controller.
If compiled as a module, the module name will be
pinctrl-microchip-sgpio.
config PINCTRL_OCELOT
tristate "Pinctrl driver for the Microsemi Ocelot and Jaguar2 SoCs"
depends on OF
depends on HAS_IOMEM
select GPIOLIB
pinctrl: Add SX150X GPIO Extender Pinctrl Driver Since the I2C sx150x GPIO expander driver uses platform_data to manage the pins configurations, rewrite the driver as a pinctrl driver using pinconf to get/set pin configurations from DT or debugfs. The pinctrl driver is functionnally equivalent as the gpio-only driver and can use DT for pinconf. The platform_data confirmation is dropped. This patchset removed the gpio-only driver and selects the Pinctrl driver config instead. This patchset also migrates the gpio dt-bindings to pinctrl and add the pinctrl optional properties. The driver was tested with a SX1509 device on a BeagleBone black with interrupt support and on an X86_64 machine over an I2C to USB converter. This is a fixed version that builds and runs on non-OF platforms and on arm based OF. The GPIO version is removed and the bindings are also moved to the pinctrl bindings. Changes since v2 - rebased on v4.9-rc1 - removed MODULE_DEVICE_TABLE as in upstream bb411e771b0e ("gpio: sx150x: fix implicit assumption module.h is present") Changes since v1 - Fix Kconfig descriptions on pinctrl and gpio - Fix Kconfig dependency - Remove oscio support for non-789 devices - correct typo in dt bindings - remove probe reset for non-789 devices Changes since RFC - Put #ifdef CONFIG_OF/CONFIG_OF_GPIO to remove OF code for non-of platforms - No more rely on OF_GPIO config - Moved and enhanced bindings to pinctrl bindings - Removed gpio-sx150x.c - Temporary select PINCTRL_SX150X when GPIO_SX150X - Temporary mark GPIO_SX150X as deprecated Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Tested-by: Peter Rosin <peda@axentia.se> Acked-by: Rob Herring <robh@kernel.org> ested-by: Andrey Smirnov <andrew.smirnov@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21 02:09:58 -07:00
select GPIOLIB_IRQCHIP
select GENERIC_PINCONF
select GENERIC_PINCTRL_GROUPS
select GENERIC_PINMUX_FUNCTIONS
select OF_GPIO
select REGMAP_MMIO
help
Support for the internal GPIO interfaces on Microsemi Ocelot and
Jaguar2 SoCs.
If conpiled as a module, the module name will be pinctrl-ocelot.
config PINCTRL_PALMAS
tristate "Pinctrl driver for the PALMAS Series MFD devices"
depends on OF && MFD_PALMAS
pinctrl: palmas: PINCTRL_PALMAS needs to select PINMUX Fix below build error if !PINMUX. CC drivers/pinctrl/pinctrl-palmas.o drivers/pinctrl/pinctrl-palmas.c:741:21: error: variable 'palmas_pinmux_ops' has initializer but incomplete type drivers/pinctrl/pinctrl-palmas.c:742:2: error: unknown field 'get_functions_count' specified in initializer drivers/pinctrl/pinctrl-palmas.c:742:2: warning: excess elements in struct initializer [enabled by default] drivers/pinctrl/pinctrl-palmas.c:742:2: warning: (near initialization for 'palmas_pinmux_ops') [enabled by default] drivers/pinctrl/pinctrl-palmas.c:743:2: error: unknown field 'get_function_name' specified in initializer drivers/pinctrl/pinctrl-palmas.c:743:2: warning: excess elements in struct initializer [enabled by default] drivers/pinctrl/pinctrl-palmas.c:743:2: warning: (near initialization for 'palmas_pinmux_ops') [enabled by default] drivers/pinctrl/pinctrl-palmas.c:744:2: error: unknown field 'get_function_groups' specified in initializer drivers/pinctrl/pinctrl-palmas.c:744:2: warning: excess elements in struct initializer [enabled by default] drivers/pinctrl/pinctrl-palmas.c:744:2: warning: (near initialization for 'palmas_pinmux_ops') [enabled by default] drivers/pinctrl/pinctrl-palmas.c:745:2: error: unknown field 'enable' specified in initializer drivers/pinctrl/pinctrl-palmas.c:745:2: warning: excess elements in struct initializer [enabled by default] drivers/pinctrl/pinctrl-palmas.c:745:2: warning: (near initialization for 'palmas_pinmux_ops') [enabled by default] make[2]: *** [drivers/pinctrl/pinctrl-palmas.o] Error 1 make[1]: *** [drivers/pinctrl] Error 2 make: *** [drivers] Error 2 Signed-off-by: Axel Lin <axel.lin@ingics.com> Acked-by: Laxman Dewangan <ldewangan@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-08-21 23:30:08 -07:00
select PINMUX
select GENERIC_PINCONF
help
Palmas device supports the configuration of pins for different
functionality. This driver supports the pinmux, push-pull and
open drain configuration for the Palmas series devices like
TPS65913, TPS80036 etc.
config PINCTRL_PEF2256
tristate "Lantiq PEF2256 (FALC56) pin controller driver"
depends on OF && FRAMER_PEF2256
select PINMUX
select PINCONF
select GENERIC_PINCONF
help
This option enables the pin controller support for the Lantiq PEF2256
framer, also known as FALC56.
If unsure, say N.
To compile this driver as a module, choose M here: the
module will be called pinctrl-pef2256.
config PINCTRL_PIC32
bool "Microchip PIC32 pin controller driver"
depends on OF
depends on MACH_PIC32
select PINMUX
select GENERIC_PINCONF
select GPIOLIB_IRQCHIP
select OF_GPIO
help
This is the pin controller and gpio driver for Microchip PIC32
microcontrollers. This option is selected automatically when specific
machine and arch are selected to build.
config PINCTRL_PIC32MZDA
def_bool y if PIC32MZDA
select PINCTRL_PIC32
config PINCTRL_PISTACHIO
bool "IMG Pistachio SoC pinctrl driver"
depends on OF && (MIPS || COMPILE_TEST)
depends on GPIOLIB
select PINMUX
select GENERIC_PINCONF
select GPIOLIB_IRQCHIP
select OF_GPIO
help
This support pinctrl and GPIO driver for IMG Pistachio SoC.
config PINCTRL_RK805
tristate "Pinctrl and GPIO driver for RK805 PMIC"
depends on MFD_RK8XX
select GPIOLIB
select PINMUX
select GENERIC_PINCONF
help
This selects the pinctrl driver for RK805.
config PINCTRL_ROCKCHIP
tristate "Rockchip gpio and pinctrl driver"
depends on ARCH_ROCKCHIP || COMPILE_TEST
depends on OF
select GPIOLIB
select PINMUX
select GENERIC_PINCONF
select GENERIC_IRQ_CHIP
select MFD_SYSCON
select OF_GPIO
default ARCH_ROCKCHIP
help
This support pinctrl and GPIO driver for Rockchip SoCs.
config PINCTRL_SCMI
tristate "Pinctrl driver using SCMI protocol interface"
depends on ARM_SCMI_PROTOCOL || COMPILE_TEST
select PINMUX
select GENERIC_PINCONF
help
This driver provides support for pinctrl which is controlled
by firmware that implements the SCMI interface.
It uses SCMI Message Protocol to interact with the
firmware providing all the pinctrl controls.
config PINCTRL_SINGLE
tristate "One-register-per-pin type device tree based pinctrl driver"
depends on OF
depends on HAS_IOMEM
select GENERIC_PINCTRL_GROUPS
select GENERIC_PINMUX_FUNCTIONS
select GENERIC_PINCONF
help
This selects the device tree based generic pinctrl driver.
config PINCTRL_ST
bool
depends on OF
select PINMUX
select PINCONF
select GPIOLIB_IRQCHIP
config PINCTRL_STMFX
tristate "STMicroelectronics STMFX GPIO expander pinctrl driver"
depends on I2C
depends on OF_GPIO
select GENERIC_PINCONF
select GPIOLIB_IRQCHIP
select MFD_STMFX
help
Driver for STMicroelectronics Multi-Function eXpander (STMFX)
GPIO expander.
This provides a GPIO interface supporting inputs and outputs,
and configuring push-pull, open-drain, and can also be used as
interrupt-controller.
config PINCTRL_SX150X
bool "Semtech SX150x I2C GPIO expander pinctrl driver"
depends on I2C=y
select PINMUX
select PINCONF
select GENERIC_PINCONF
select GPIOLIB
select GPIOLIB_IRQCHIP
select REGMAP
help
Say Y here to provide support for Semtech SX150x-series I2C
GPIO expanders as pinctrl module.
Compatible models include:
- 8 bits: sx1508q, sx1502q
- 16 bits: sx1509q, sx1506q
config PINCTRL_TB10X
bool
depends on OF && ARC_PLAT_TB10X
select GPIOLIB
config PINCTRL_TPS6594
tristate "Pinctrl and GPIO driver for TI TPS6594 PMIC"
depends on OF && MFD_TPS6594
default MFD_TPS6594
select PINMUX
select GPIOLIB
select REGMAP
select GPIO_REGMAP
select GENERIC_PINCONF
help
Say Y to select the pinmuxing and GPIOs driver for the TPS6594
PMICs chip family.
This driver can also be built as a module
called tps6594-pinctrl.
2015-01-09 08:43:48 -07:00
config PINCTRL_ZYNQ
bool "Pinctrl driver for Xilinx Zynq"
depends on ARCH_ZYNQ
select PINMUX
select GENERIC_PINCONF
help
This selects the pinctrl driver for Xilinx Zynq.
2015-01-09 08:43:48 -07:00
config PINCTRL_ZYNQMP
tristate "Pinctrl driver for Xilinx ZynqMP"
depends on ZYNQMP_FIRMWARE
select PINMUX
select GENERIC_PINCONF
default ZYNQMP_FIRMWARE
help
This selects the pinctrl driver for Xilinx ZynqMP platform.
This driver will query the pin information from the firmware
and allow configuring the pins.
Configuration can include the mux function to select on those
pin(s)/group(s), and various pin configuration parameters
such as pull-up, slew rate, etc.
This driver can also be built as a module. If so, the module
will be called pinctrl-zynqmp.
config PINCTRL_MLXBF3
tristate "NVIDIA BlueField-3 SoC Pinctrl driver"
depends on (MELLANOX_PLATFORM && ARM64) || COMPILE_TEST
select PINMUX
select GPIOLIB
select GPIOLIB_IRQCHIP
help
Say Y to select the pinctrl driver for BlueField-3 SoCs.
This pin controller allows selecting the mux function for
each pin. This driver can also be built as a module called
pinctrl-mlxbf3.
source "drivers/pinctrl/actions/Kconfig"
source "drivers/pinctrl/aspeed/Kconfig"
source "drivers/pinctrl/bcm/Kconfig"
source "drivers/pinctrl/berlin/Kconfig"
source "drivers/pinctrl/cirrus/Kconfig"
source "drivers/pinctrl/freescale/Kconfig"
source "drivers/pinctrl/intel/Kconfig"
source "drivers/pinctrl/mediatek/Kconfig"
source "drivers/pinctrl/meson/Kconfig"
source "drivers/pinctrl/mvebu/Kconfig"
source "drivers/pinctrl/nomadik/Kconfig"
source "drivers/pinctrl/nuvoton/Kconfig"
source "drivers/pinctrl/nxp/Kconfig"
source "drivers/pinctrl/pxa/Kconfig"
source "drivers/pinctrl/qcom/Kconfig"
source "drivers/pinctrl/realtek/Kconfig"
source "drivers/pinctrl/renesas/Kconfig"
source "drivers/pinctrl/samsung/Kconfig"
source "drivers/pinctrl/sophgo/Kconfig"
source "drivers/pinctrl/spear/Kconfig"
source "drivers/pinctrl/sprd/Kconfig"
source "drivers/pinctrl/starfive/Kconfig"
source "drivers/pinctrl/stm32/Kconfig"
source "drivers/pinctrl/sunplus/Kconfig"
source "drivers/pinctrl/sunxi/Kconfig"
source "drivers/pinctrl/tegra/Kconfig"
pinctrl: Introduce TI IOdelay configuration driver SoC family such as DRA7 family of processors have, in addition to the regular muxing of pins (as done by pinctrl-single), a separate hardware module called IODelay which is also expected to be configured. The "IODelay" module has it's own register space that is independent of the control module and the padconf register area. With recent changes to the pinctrl framework, we can now support this hardware with a reasonably minimal driver by using #pinctrl-cells, GENERIC_PINCTRL_GROUPS and GENERIC_PINMUX_FUNCTIONS. It is advocated strongly in TI's official documentation considering the existing design of the DRA7 family of processors during mux or IODelay reconfiguration, there is a potential for a significant glitch which may cause functional impairment to certain hardware. It is hence recommended to do as little of muxing as absolutely necessary without I/O isolation (which can only be done in initial stages of bootloader). NOTE: with the system wide I/O isolation scheme present in DRA7 SoC family, it is not reasonable to do stop all I/O operations for every such pad configuration scheme. So, we will let it glitch when used in this mode. Even with the above limitation, certain functionality such as MMC has mandatory need for IODelay reconfiguration requirements, depending on speed of transfer. In these cases, with careful examination of usecase involved, the expected glitch can be controlled such that it does not impact functionality. In short, IODelay module support as a padconf driver being introduced here is not expected to do SoC wide I/O Isolation and is meant for a limited subset of IODelay configuration requirements that need to be dynamic and whose glitchy behavior will not cause functionality failure for that interface. IMPORTANT NOTE: we take the approach of keeping LOCK_BITs cleared to 0x0 at all times, even when configuring Manual IO Timing Modes. This is done by eliminating the LOCK_BIT=1 setting from Step of the Manual IO timing Mode configuration procedure. This option leaves the CFG_* registers unprotected from unintended writes to the CTRL_CORE_PAD_* registers while Manual IO Timing Modes are configured. This approach is taken to allow for a generic driver to exist in kernel world that has to be used carefully in required usecases. Signed-off-by: Nishanth Menon <nm@ti.com> Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com> [tony@atomide.com: updated to use generic pinctrl functions, added binding documentation, updated comments] Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-05 11:54:14 -07:00
source "drivers/pinctrl/ti/Kconfig"
source "drivers/pinctrl/uniphier/Kconfig"
source "drivers/pinctrl/visconti/Kconfig"
source "drivers/pinctrl/vt8500/Kconfig"
endif