14 Aug, 2017

1 commit


03 Jan, 2017

1 commit


18 Apr, 2012

1 commit


05 Mar, 2012

2 commits

  • The pinctrl mapping table can now contain entries to:
    * Set the mux function of a pin group
    * Apply a set of pin config options to a pin or a group

    This allows pinctrl_select_state() to apply pin configs settings as well
    as mux settings.

    v3: Fix find_pinctrl() to iterate over the correct list.
    s/_MUX_CONFIGS_/_CONFIGS_/ in mapping table macros.
    Fix documentation to use correct mapping table macro.
    v2: Added numerous extra PIN_MAP_*() special-case macros.
    Fixed kerneldoc typo. Delete pinctrl_get_pin_id() and
    replace it with pin_get_from_name(). Various minor fixes.
    Updates due to rebase.

    Signed-off-by: Stephen Warren
    Acked-by: Dong Aisheng
    Signed-off-by: Linus Walleij

    Stephen Warren
     
  • This change separates two aspects of struct pinctrl:

    a) The data representation of the parsed mapping table, into:

    1) The top-level struct pinctrl object, a single entity returned
    by pinctrl_get().

    2) The parsed version of each mapping table entry, struct
    pinctrl_setting, of which there is one per mapping table entry.

    b) The code that handles this; the code for (1) above is in core.c, and
    the code to parse/execute each entry in (2) above is in pinmux.c, while
    the iteration over multiple settings is lifted to core.c.

    This will allow the following future changes:

    1) pinctrl_get() API rework, so that struct pinctrl represents all states
    for the device, and the device can select between them without calling
    put()/get() again.

    2) To support that, a struct pinctrl_state object will be inserted into
    the data model between the struct pinctrl and struct pinctrl_setting.

    3) The mapping table will be extended to allow specification of pin config
    settings too. To support this, struct pinctrl_setting will be enhanced
    to store either mux settings or config settings, and functions will be
    added to pinconf.c to parse/execute pin configuration settings.

    Signed-off-by: Stephen Warren
    Acked-by: Linus Walleij
    Acked-by: Dong Aisheng
    Signed-off-by: Linus Walleij

    Stephen Warren
     

02 Mar, 2012

1 commit

  • At present, pinctrl_get() assumes that all matching mapping table entries
    have the same "function" value, albeit potentially applied to different
    pins/groups.

    This change removes this restriction; pinctrl_get() can now handle a set
    of mapping tables where different functions are applied to the various
    pins/groups.

    Signed-off-by: Stephen Warren
    Signed-off-by: Linus Walleij

    Stephen Warren
     

23 Feb, 2012

1 commit


11 Feb, 2012

2 commits

  • This moves the per-devices struct pinctrl handles and device map
    over from the pinmux part of the subsystem to the core pinctrl part.
    This makes the device handles core infrastructure with the goal of
    using these handles also for pin configuration, so that device
    drivers (or boards etc) will need one and only one handle to the
    pin control core.

    Acked-by: Stephen Warren
    Signed-off-by: Linus Walleij

    Linus Walleij
     
  • Since we want to use the former pinmux handles and mapping tables for
    generic control involving both muxing and configuration we begin
    refactoring by renaming them from pinmux_* to pinctrl_*.

    ChangeLog v1->v2:
    - Also rename the PINMUX_* macros in machine.h to PIN_ as indicated
    in the documentation so as to reflect the generic nature of these
    mapping entries from now on.

    Acked-by: Stephen Warren
    Signed-off-by: Linus Walleij

    Linus Walleij
     

26 Jan, 2012

1 commit

  • This is needed as otherwise we can get the following when
    dealing with buggy data in a pinmux driver for
    pinmux_search_function:

    Unable to handle kernel NULL pointer dereference at virtual
    address 00000000
    ...
    PC is at strcmp+0xc/0x34
    LR is at pinmux_get+0x350/0x8f4
    ...

    As we need pctldev initialized to call ops->list_functions,
    let's initialize it before check_ops calls and pass the
    pctldev to the check_ops functions. Do this for both pinmux
    and pinconf check_ops functions.

    Signed-off-by: Tony Lindgren
    Signed-off-by: Linus Walleij

    Tony Lindgren
     

13 Oct, 2011

1 commit

  • 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
    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
    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
    Cc: Joe Perches
    Cc: Russell King
    Acked-by: Grant Likely
    Acked-by: Stephen Warren
    Tested-by: Barry Song
    Signed-off-by: Linus Walleij

    Linus Walleij