2019-05-19 15:07:45 +03:00
# 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 22:50:54 +04:00
#
# PINCTRL infrastructure and drivers
#
2017-10-06 08:08:05 +03:00
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 22:50:54 +04:00
2017-10-06 08:08:05 +03:00
if PINCTRL
2011-11-06 00:28:46 +04:00
2016-12-30 17:04:43 +03:00
config GENERIC_PINCTRL_GROUPS
2016-12-27 20:20:00 +03:00
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 22:50:54 +04:00
config PINMUX
2014-06-03 12:02:36 +04:00
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 20:14:33 +04:00
2016-12-27 20:20:01 +03:00
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 20:14:33 +04:00
config PINCONF
2014-06-03 12:02:36 +04:00
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 22:50:54 +04:00
2011-11-24 21:27:15 +04:00
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 22:50:54 +04:00
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.
2017-04-03 15:47:04 +03:00
config PINCTRL_ARTPEC6
2019-11-21 06:19:41 +03:00
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
2017-04-03 15:47:04 +03:00
2013-10-02 19:50:29 +04:00
config PINCTRL_AS3722
2016-06-14 00:10:22 +03:00
tristate "Pinctrl and GPIO driver for ams AS3722 PMIC"
2013-10-02 19:50:29 +04:00
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.
2017-12-05 17:46:40 +03:00
config PINCTRL_AXP209
tristate "X-Powers AXP209 PMIC pinctrl and GPIO Support"
depends on MFD_AXP20X
2017-12-14 12:43:35 +03:00
depends on OF
select PINMUX
select GENERIC_PINCONF
select GPIOLIB
2017-12-05 17:46:40 +03:00
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 yes to enable pinctrl and GPIO support for the AXP209 PMIC
2012-07-12 19:35:02 +04:00
config PINCTRL_AT91
bool "AT91 pinctrl driver"
depends on OF
depends on ARCH_AT91
select PINMUX
select PINCONF
2014-04-16 00:09:41 +04:00
select GPIOLIB
select OF_GPIO
select GPIOLIB_IRQCHIP
2012-07-12 19:35:02 +04:00
help
Say Y here to enable the at91 pinctrl driver
2015-09-16 18:36:57 +03:00
config PINCTRL_AT91PIO4
bool "AT91 PIO4 pinctrl driver"
depends on OF
2020-05-23 14:45:26 +03:00
depends on ARCH_AT91 || COMPILE_TEST
2015-09-16 18:36:57 +03:00
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.
2015-03-10 10:02:19 +03:00
config PINCTRL_AMD
2016-02-11 14:06:37 +03:00
tristate "AMD GPIO pin control"
2017-11-13 13:04:27 +03:00
depends on HAS_IOMEM
2020-05-07 14:37:51 +03:00
depends on ACPI || COMPILE_TEST
2017-10-11 13:04:35 +03:00
select GPIOLIB
2015-03-10 10:02:19 +03:00
select GPIOLIB_IRQCHIP
2017-09-26 16:51:28 +03:00
select PINMUX
2015-03-10 10:02:19 +03:00
select PINCONF
select GENERIC_PINCONF
help
driver for memory mapped GPIO functionality on AMD platforms
(x86 or arm).Most 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.
2019-04-24 15:02:23 +03:00
config PINCTRL_BM1880
bool "Bitmain BM1880 Pinctrl driver"
2019-04-25 11:32:24 +03:00
depends on OF && (ARCH_BITMAIN || COMPILE_TEST)
default ARCH_BITMAIN
2019-04-24 15:02:23 +03:00
select PINMUX
help
Pinctrl driver for Bitmain BM1880 SoC.
2016-11-28 19:40:25 +03:00
config PINCTRL_DA850_PUPD
tristate "TI DA850/OMAP-L138/AM18XX pullup/pulldown 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
pullup/pulldown pin groups.
2020-01-08 13:47:46 +03:00
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 yes to enable pinctrl and GPIO support for the DA9062 PMIC.
2015-05-05 13:55:10 +03:00
config PINCTRL_DIGICOLOR
bool
depends on OF && (ARCH_DIGICOLOR || COMPILE_TEST)
select PINMUX
select GENERIC_PINCONF
2012-08-28 14:44:59 +04:00
config PINCTRL_LANTIQ
bool
depends on LANTIQ
select PINMUX
select PINCONF
2015-04-28 01:14:08 +03:00
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).
2012-05-20 02:33:56 +04:00
config PINCTRL_FALCON
bool
depends on SOC_FALCON
depends on PINCTRL_LANTIQ
2017-08-06 00:04:08 +03:00
config PINCTRL_GEMINI
bool
depends on ARCH_GEMINI
default ARCH_GEMINI
select PINMUX
2017-10-28 16:37:18 +03:00
select GENERIC_PINCONF
2017-08-06 00:04:08 +03:00
select MFD_SYSCON
2020-04-07 20:38:49 +03:00
config PINCTRL_MCP23S08_I2C
tristate
select REGMAP_I2C
config PINCTRL_MCP23S08_SPI
tristate
select REGMAP_SPI
2017-05-15 12:24:25 +03:00
config PINCTRL_MCP23S08
tristate "Microchip MCP23xxx I/O expander"
depends on SPI_MASTER || I2C
2017-10-11 13:04:35 +03:00
select GPIOLIB
2017-05-15 12:24:25 +03:00
select GPIOLIB_IRQCHIP
2017-05-15 12:24:26 +03:00
select GENERIC_PINCONF
2020-04-07 20:38:49 +03:00
select PINCTRL_MCP23S08_I2C if I2C
select PINCTRL_MCP23S08_SPI if SPI_MASTER
2017-05-15 12:24:25 +03:00
help
2018-02-15 17:56:03 +03:00
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.
2017-05-15 12:24:25 +03:00
2016-05-11 10:34:21 +03:00
config PINCTRL_OXNAS
bool
depends on OF
select PINMUX
select PINCONF
select GENERIC_PINCONF
select GPIOLIB
select OF_GPIO
select GPIOLIB_IRQCHIP
select MFD_SYSCON
2013-06-11 00:16:22 +04:00
config PINCTRL_ROCKCHIP
bool
select PINMUX
select GENERIC_PINCONF
select GENERIC_IRQ_CHIP
2014-05-05 15:58:20 +04:00
select MFD_SYSCON
2013-06-11 00:16:22 +04:00
2017-06-22 17:54:29 +03:00
config PINCTRL_RZA1
bool "Renesas RZ/A1 gpio and pinctrl driver"
depends on OF
depends on ARCH_R7S72100 || COMPILE_TEST
select GPIOLIB
select GENERIC_PINCTRL_GROUPS
select GENERIC_PINMUX_FUNCTIONS
select GENERIC_PINCONF
help
This selects pinctrl driver for Renesas RZ/A1 platforms.
2018-11-15 19:15:27 +03:00
config PINCTRL_RZA2
bool "Renesas RZ/A2 gpio and pinctrl driver"
depends on OF
depends on ARCH_R7S9210 || COMPILE_TEST
select GPIOLIB
select GENERIC_PINCTRL_GROUPS
select GENERIC_PINMUX_FUNCTIONS
select GENERIC_PINCONF
help
This selects GPIO and pinctrl driver for Renesas RZ/A2 platforms.
2018-09-26 12:10:52 +03:00
config PINCTRL_RZN1
bool "Renesas RZ/N1 pinctrl driver"
depends on OF
depends on ARCH_RZN1 || COMPILE_TEST
select GENERIC_PINCTRL_GROUPS
select GENERIC_PINMUX_FUNCTIONS
select GENERIC_PINCONF
help
This selects pinctrl driver for Renesas RZ/N1 devices.
2012-07-10 13:05:46 +04:00
config PINCTRL_SINGLE
tristate "One-register-per-pin type device tree based pinctrl driver"
depends on OF
2017-11-13 13:04:27 +03:00
depends on HAS_IOMEM
2016-12-27 20:20:02 +03:00
select GENERIC_PINCTRL_GROUPS
2016-12-27 20:20:03 +03:00
select GENERIC_PINMUX_FUNCTIONS
2013-02-17 15:42:55 +04:00
select GENERIC_PINCONF
2012-07-10 13:05:46 +04:00
help
This selects the device tree based generic pinctrl driver.
2011-12-19 02:44:26 +04:00
config PINCTRL_SIRF
2015-01-11 16:56:41 +03:00
bool "CSR SiRFprimaII pin controller driver"
2012-09-27 13:56:30 +04:00
depends on ARCH_SIRF
2011-10-09 14:11:13 +04:00
select PINMUX
pinctrl: sirf: add sirf atlas7 pinctrl and gpio support
The Pinctrl module (ioc) controls the Pad's function select
(each pad can have 8 functions), Pad's Drive Strength, Pad's
Pull Select and Pad's Input Disable status.
The ioc has two modules, ioc_top & ioc_rtc. Both of these two
modules have function select/clear, Pull select and Drive
Strength registers. But only ioc_rtc has input-disable
registers. The Pads on ioc_top have to access ioc_rtc to set
their input-disable status and intpu-disable-value.
So have to use one ioc driver instance to drive these two
ioc modules at the same time, and each ioc module will be
treat as one bank on the "IOC Device".
The GPIO Controller controls the GPIO status if the Pad has
been config as GPIO by Pinctrl already. Includes the GPIO
Input/output, Interrupt type, Interrupt Status, and Set/Get
Values.
The GPIO pull up/down are controlled by Pinctrl.
There are 7 GPIO Groups and splited into 3 MACROs in atlas7.
The GPIO Groups in one MACRO share one GPIO controllers, each
GPIO Group are treated as one GPIO bank.
For example:
In VDIFM macro, there is one GPIO Controller, it has 3 banks
to control 3 gpio groups. Its gpio name space is from 0 to 95.
The Device Tree can be written as following:
gpio-ranges = <&pinctrl 0 0 0>,
<&pinctrl 32 0 0>,
<&pinctrl 64 0 0>;
gpio-ranges-group-names = "gnss_gpio_grp",
"lcd_vip_gpio_grp",
"sdio_i2s_gpio_grp";
bank#0 is from 0~31, the pins are from pinctrl's "gnss_gpio_grp".
bank#2 is from 32~63, the pins are from pinctrl's "lcd_vip_gpio_grp".
bank#3 is from 64~95, the pins are from pinctrl's "sdio_i2s_gpio_grp".
Signed-off-by: Wei Chen <Wei.Chen@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-18 10:28:32 +03:00
select PINCONF
select GENERIC_PINCONF
2014-04-15 10:43:47 +04:00
select GPIOLIB_IRQCHIP
2011-10-09 14:11:13 +04:00
2016-10-21 12:09:58 +03:00
config PINCTRL_SX150X
bool "Semtech SX150x I2C GPIO expander pinctrl driver"
2017-10-11 13:04:35 +03:00
depends on I2C=y
2016-10-21 12:09:58 +03:00
select PINMUX
select PINCONF
select GENERIC_PINCONF
2017-10-11 13:04:35 +03:00
select GPIOLIB
2016-10-21 12:09:58 +03:00
select GPIOLIB_IRQCHIP
2016-11-07 19:53:16 +03:00
select REGMAP
2016-10-21 12:09:58 +03:00
help
Say yes 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
2015-05-06 22:59:03 +03:00
config PINCTRL_PISTACHIO
def_bool y if MACH_PISTACHIO
depends on GPIOLIB
select PINMUX
select GENERIC_PINCONF
select GPIOLIB_IRQCHIP
select OF_GPIO
2013-06-20 18:05:38 +04:00
config PINCTRL_ST
bool
depends on OF
select PINMUX
select PINCONF
2014-04-08 16:45:47 +04:00
select GPIOLIB_IRQCHIP
2013-06-20 18:05:38 +04:00
2019-05-09 11:58:51 +03:00
config PINCTRL_STMFX
tristate "STMicroelectronics STMFX GPIO expander pinctrl driver"
2019-05-10 16:39:18 +03:00
depends on I2C
2019-05-24 10:32:05 +03:00
depends on OF_GPIO
2019-05-09 11:58:51 +03:00
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.
2011-12-19 02:44:26 +04:00
config PINCTRL_U300
bool "U300 pin controller driver"
2011-05-02 22:54:38 +04:00
depends on ARCH_U300
select PINMUX
2011-11-17 00:58:10 +04:00
select GENERIC_PINCONF
2011-11-06 00:28:46 +04:00
2011-11-16 12:22:59 +04:00
config PINCTRL_COH901
bool "ST-Ericsson U300 COH 901 335/571 GPIO"
2012-06-18 22:07:50 +04:00
depends on GPIOLIB && ARCH_U300 && PINCTRL_U300
2014-03-25 16:37:17 +04:00
select GPIOLIB_IRQCHIP
2011-11-16 12:22:59 +04:00
help
Say yes here to support GPIO interface on ST-Ericsson U300.
The names of the two IP block variants supported are
COH 901 335 and COH 901 571/3. They contain 3, 5 or 7
ports of 8 GPIO pins each.
2016-05-13 08:19:15 +03:00
config PINCTRL_MAX77620
tristate "MAX77620/MAX20024 Pincontrol support"
2016-10-28 11:19:05 +03:00
depends on MFD_MAX77620 && OF
2016-06-13 18:18:35 +03:00
select PINMUX
2016-05-13 08:19:15 +03:00
select GENERIC_PINCONF
help
Say Yes here to enable Pin control support for Maxim PMIC MAX77620.
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.
2013-08-06 17:12:35 +04:00
config PINCTRL_PALMAS
2016-06-14 00:10:21 +03:00
tristate "Pinctrl driver for the PALMAS Series MFD devices"
2013-08-06 17:12:35 +04:00
depends on OF && MFD_PALMAS
2013-08-22 10:30:08 +04:00
select PINMUX
2013-08-06 17:12:35 +04:00
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.
2016-02-02 01:48:30 +03:00
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
2015-01-09 18:43:48 +03:00
config PINCTRL_ZYNQ
bool "Pinctrl driver for Xilinx Zynq"
depends on ARCH_ZYNQ
select PINMUX
select GENERIC_PINCONF
help
2015-11-30 10:57:35 +03:00
This selects the pinctrl driver for Xilinx Zynq.
2015-01-09 18:43:48 +03:00
2017-05-12 19:52:56 +03:00
config PINCTRL_INGENIC
bool "Pinctrl driver for the Ingenic JZ47xx SoCs"
2018-08-21 19:42:35 +03:00
default MACH_INGENIC
2017-05-29 14:40:45 +03:00
depends on OF
2018-08-21 19:42:35 +03:00
depends on MIPS || COMPILE_TEST
2017-05-12 19:52:56 +03:00
select GENERIC_PINCONF
select GENERIC_PINCTRL_GROUPS
select GENERIC_PINMUX_FUNCTIONS
2018-08-21 19:42:32 +03:00
select GPIOLIB
select GPIOLIB_IRQCHIP
2017-05-12 19:52:56 +03:00
select REGMAP_MMIO
2017-08-21 04:28:40 +03:00
config PINCTRL_RK805
tristate "Pinctrl and GPIO driver for RK805 PMIC"
depends on MFD_RK808
select GPIOLIB
select PINMUX
select GENERIC_PINCONF
help
This selects the pinctrl driver for RK805.
2018-01-06 03:09:26 +03:00
config PINCTRL_OCELOT
2018-12-20 17:44:31 +03:00
bool "Pinctrl driver for the Microsemi Ocelot and Jaguar2 SoCs"
2018-01-06 03:09:26 +03:00
depends on OF
2018-12-22 13:15:04 +03:00
depends on HAS_IOMEM
2018-01-06 03:09:26 +03:00
select GPIOLIB
2018-07-25 15:26:21 +03:00
select GPIOLIB_IRQCHIP
2018-01-06 03:09:26 +03:00
select GENERIC_PINCONF
select GENERIC_PINCTRL_GROUPS
select GENERIC_PINMUX_FUNCTIONS
2018-12-20 17:44:31 +03:00
select OF_GPIO
2018-01-06 03:09:26 +03:00
select REGMAP_MMIO
2018-04-04 20:22:52 +03:00
source "drivers/pinctrl/actions/Kconfig"
2016-08-30 10:54:24 +03:00
source "drivers/pinctrl/aspeed/Kconfig"
2015-03-05 03:35:49 +03:00
source "drivers/pinctrl/bcm/Kconfig"
2014-05-19 21:36:29 +04:00
source "drivers/pinctrl/berlin/Kconfig"
2014-09-03 15:37:38 +04:00
source "drivers/pinctrl/freescale/Kconfig"
2014-10-24 16:16:52 +04:00
source "drivers/pinctrl/intel/Kconfig"
2012-10-25 01:38:58 +04:00
source "drivers/pinctrl/mvebu/Kconfig"
2014-07-11 16:57:06 +04:00
source "drivers/pinctrl/nomadik/Kconfig"
2018-08-08 12:25:26 +03:00
source "drivers/pinctrl/nuvoton/Kconfig"
2015-11-21 21:04:53 +03:00
source "drivers/pinctrl/pxa/Kconfig"
2014-07-09 15:55:12 +04:00
source "drivers/pinctrl/qcom/Kconfig"
2014-07-10 16:03:27 +04:00
source "drivers/pinctrl/samsung/Kconfig"
2012-12-16 02:51:19 +04:00
source "drivers/pinctrl/sh-pfc/Kconfig"
2012-03-28 20:57:07 +04:00
source "drivers/pinctrl/spear/Kconfig"
2017-08-17 09:50:38 +03:00
source "drivers/pinctrl/sprd/Kconfig"
2016-01-14 15:16:30 +03:00
source "drivers/pinctrl/stm32/Kconfig"
2014-04-18 20:53:02 +04:00
source "drivers/pinctrl/sunxi/Kconfig"
2016-01-23 18:30:08 +03:00
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 21:54:14 +03:00
source "drivers/pinctrl/ti/Kconfig"
2015-07-14 05:40:01 +03:00
source "drivers/pinctrl/uniphier/Kconfig"
2013-02-20 00:32:19 +04:00
source "drivers/pinctrl/vt8500/Kconfig"
2015-01-21 08:28:15 +03:00
source "drivers/pinctrl/mediatek/Kconfig"
2017-04-24 16:01:13 +03:00
source "drivers/pinctrl/zte/Kconfig"
2017-10-12 15:40:25 +03:00
source "drivers/pinctrl/meson/Kconfig"
2018-05-21 13:00:01 +03:00
source "drivers/pinctrl/cirrus/Kconfig"
2012-03-28 20:57:07 +04:00
2012-08-28 14:44:59 +04:00
config PINCTRL_XWAY
bool
depends on SOC_TYPE_XWAY
depends on PINCTRL_LANTIQ
2013-10-15 17:39:38 +04:00
config PINCTRL_TB10X
bool
2015-04-15 11:00:35 +03:00
depends on OF && ARC_PLAT_TB10X
select GPIOLIB
2013-10-15 17:39:38 +04:00
2019-11-15 12:25:07 +03:00
config PINCTRL_EQUILIBRIUM
tristate "Generic pinctrl and GPIO driver for Intel Lightning Mountain SoC"
2019-12-10 19:44:46 +03:00
depends on OF && HAS_IOMEM
2020-05-07 14:36:25 +03:00
depends on X86 || COMPILE_TEST
2019-11-15 12:25:07 +03:00
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 pinctrl driver is a pinctrl & GPIO driver for Intel Lightning
Mountain network processor SoC that supports both the linux GPIO and pin
control frameworks. It provides interfaces to setup pinmux, assign desired
pin functions, configure GPIO attributes for LGM SoC pins. Pinmux and
pinconf settings are retrieved from device tree.
2017-10-06 08:08:05 +03:00
endif
