Commit Graph

38 Commits

Author SHA1 Message Date
Linus Walleij
44c7288f79 gpio: move gpiod_set_array_value_priv()
This renames gpiod_set_array_value_priv() to
gpiod_set_array_value_complex() and moves it to the gpiolib.h
private header file so we can reuse it in the subsystem.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-26 10:51:36 +02:00
Linus Walleij
df4878e969 gpio: store reflect the label to userspace
The gpio_chip label is useful for userspace to understand what
kind of GPIO chip it is dealing with. Let's store a copy of this
label in the gpio_device, add it to the struct passed to userspace
for GPIO_GET_CHIPINFO_IOCTL and modify lsgpio to show it.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-19 09:48:41 +01:00
Linus Walleij
43c54ecade gpio: move the subdriver data pointer into gpio_device
We move to manage this pointer under gpiolib control rather than
leave it in the subdevice's gpio_chip. We can not NULL it after
gpiochip_remove so at to keep things tight.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-16 00:20:02 +01:00
Linus Walleij
20ec3e39fc gpio: move the pin ranges into gpio_device
Instead of keeping this reference to the pin ranges in the
client driver-supplied gpio_chip, move it to the internal
gpio_device as the drivers have no need to inspect this.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-16 00:20:02 +01:00
Linus Walleij
fdeb8e1547 gpio: reflect base and ngpio into gpio_device
Some information about the GPIO chip need to stay around also
after the gpio_chip has been removed and only the gpio_device
persist. The base and ngpio are such things, for example we
don't want a new chip arriving to overlap the number space
of a dangling gpio_device, and the chardev may still query
the device for the number of lines etc.

Note that the code that assigns base and insert gpio_device
into the global list no longer check for a missing gpio_chip:
we respect the number space allocated by any other gpio_device.

As a consequence of the gdev being referenced directly from
the gpio_desc, we need to verify it differently from all
in-kernel API calls that fall through to direct queries to
the gpio_chip vtable: we first check that desc is !NULL, then
that desc->gdev is !NULL, then, if desc->gdev->chip is NULL,
we *BAIL OUT* without any error, so as to manage the case
where operations are requested on a device that is gone.

These checks were non-uniform and partly missing in the past:
so to simplify: create the macros VALIDATE_DESC() that will
return -EINVAL if the desc or desc->gdev is missing and just
0 if the chip is gone, and conversely VALIDATE_DESC_VOID()
for the case where the function does not return an error.
By using these macros, we get warning messages about missing
gdev with reference to the right function in the kernel log.

Despite the macro business this simplifies the code and make
it more readable than if we copy/paste the same descriptor
checking code into all code ABI call sites (IMHO).

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-11 20:29:46 +01:00
Linus Walleij
1c3cdb1861 gpio: move descriptors into gpio_device
We need gpio_device to hold the descriptors so that they can
be lifecycled with the struct gpio_device held from userspace.
Move the descriptor array into gpio_device. Also rename it from
"desc" (singularis) to "descs" (pluralis) to reflect the fact
that it is an array.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-11 20:29:45 +01:00
Linus Walleij
afbc4f312b gpio: move sysfs mock device to the gpio_device
Since gpio_device is the struct that survives if the backing
gpio_chip is removed, move the sysfs mock device to this state
container so it becomes part of the dangling state of the
GPIO device on removal.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-11 18:16:54 +01:00
Linus Walleij
3c702e9987 gpio: add a userspace chardev ABI for GPIOs
A new chardev that is to be used for userspace GPIO access is
added in this patch. It is intended to gradually replace the
horribly broken sysfs ABI.

Using a chardev has many upsides:

- All operations are per-gpiochip, which is the actual
  device underlying the GPIOs, making us tie in to the
  kernel device model properly.

- Hotpluggable GPIO controllers can come and go, as this
  kind of problem has been know to userspace for character
  devices since ages, and if a gpiochip handle is held in
  userspace we know we will break something, whereas the
  sysfs is stateless.

- The one-value-per-file rule of sysfs is really hard to
  maintain when you want to twist more than one knob at a time,
  for example have in-kernel APIs to switch several GPIO
  lines at the same time, and this will be possible to do
  with a single ioctl() from userspace, saving a lot of
  context switching.

We also need to add a new bus type for GPIO. This is
necessary for example for userspace coldplug, where sysfs is
traversed to find the boot-time device nodes and create the
character devices in /dev.

This new chardev ABI is *non* *optional* and can be counted
on to be present in the future, emphasizing the preference
of this ABI.

The ABI only implements one single ioctl() to get the name
and number of GPIO lines of a chip. Even this is debatable:
see it as a minimal example for review. This ABI shall be
ruthlessly reviewed and etched in stone.

The old /sys/class/gpio is still optional to compile in,
but will be deprecated.

Unique device IDs are created using IDR, which is overkill
and insanely scalable, but also well tested.

Cc: Johan Hovold <johan@kernel.org>
Cc: Michael Welling <mwelling@ieee.org>
Cc: Markus Pargmann <mpa@pengutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-09 11:09:35 +01:00
Linus Walleij
34ffd85d9c gpio: refer to gpio device in prints and debugfs
We use the new struct device inside gpio_chip to related debug
prints and warnings, and we also add it to the debugfs dump.

Cc: Johan Hovold <johan@kernel.org>
Cc: Michael Welling <mwelling@ieee.org>
Cc: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-09 11:09:30 +01:00
Linus Walleij
ff2b135922 gpio: make the gpiochip a real device
GPIO chips have been around for years, but were never real devices,
instead they were piggy-backing on a parent device (such as a
platform_device or amba_device) but this was always optional.
GPIO chips could also exist without any device at all, with its
struct device *parent (ex *dev) pointer being set to null.

When sysfs was in use, a mock device would be created, with the
optional parent assigned, or just floating orphaned with NULL
as parent.

If sysfs is active, it will use this device as parent.

We now create a gpio_device struct containing a real
struct device and move the subsystem over to using that. The
list of struct gpio_chip:s is augmented to hold struct
gpio_device:s and we find gpio_chips:s by first looking up
the struct gpio_device.

The struct gpio_device is designed to stay around even if the
gpio_chip is removed, so as to satisfy users in userspace
that need a backing data structure to hold the state of the
session initiated with e.g. a character device even if there is
no physical chip anymore.

From this point on, gpiochips are devices.

Cc: Johan Hovold <johan@kernel.org>
Cc: Michael Welling <mwelling@ieee.org>
Cc: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-09 11:03:53 +01:00
Linus Torvalds
58cf279aca GPIO bulk updates for the v4.5 kernel cycle:
Infrastructural changes:
 
 - In struct gpio_chip, rename the .dev node to .parent to better reflect
   the fact that this is not the GPIO struct device abstraction. We will
   add that soon so this would be totallt confusing.
 
 - It was noted that the driver .get_value() callbacks was
   sometimes reporting negative -ERR values to the gpiolib core, expecting
   them to be propagated to consumer gpiod_get_value() and gpio_get_value()
   calls. This was not happening, so as there was a mess of drivers
   returning negative errors and some returning "anything else than zero"
   to indicate that a line was active. As some would have bit 31 set to
   indicate "line active" it clashed with negative error codes. This is
   fixed by the largeish series clamping values in all drivers with
   !!value to [0,1] and then augmenting the code to propagate error codes
   to consumers. (Includes some ACKed patches in other subsystems.)
 
 - Add a void *data pointer to struct gpio_chip. The container_of() design
   pattern is indeed very nice, but we want to reform the struct gpio_chip
   to be a non-volative, stateless business, and keep states internal to
   the gpiolib to be able to hold on to the state when adding a proper
   userspace ABI (character device) further down the road. To achieve this,
   drivers need a handle at the internal state that is not dependent on
   their struct gpio_chip() so we add gpiochip_add_data() and
   gpiochip_get_data() following the pattern of many other subsystems.
   All the "use gpiochip data pointer" patches transforms drivers to this
   scheme.
 
 - The Generic GPIO chip header has been merged into the general
   <linux/gpio/driver.h> header, and the custom header for that removed.
   Instead of having a separate mm_gpio_chip struct for these generic
   drivers, merge that into struct gpio_chip, simplifying the code and
   removing the need for separate and confusing includes.
 
 Misc improvements:
 
 - Stabilize the way GPIOs are looked up from the ACPI legacy
   specification.
 
 - Incremental driver features for PXA, PCA953X, Lantiq (patches from the
   OpenWRT community), RCAR, Zynq, PL061, 104-idi-48
 
 New drivers:
 
 - Add a GPIO chip to the ALSA SoC AC97 driver.
 
 - Add a new Broadcom NSP SoC driver (this lands in the pinctrl dir, but
   the branch is merged here too to account for infrastructural changes).
 
 - The sx150x driver now supports the sx1502.
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Merge tag 'gpio-v4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "Here is the bulk of GPIO changes for v4.5.

  Notably there are big refactorings mostly by myself, aimed at getting
  the gpio_chip into a shape that makes me believe I can proceed to
  preserve state for a proper userspace ABI (character device) that has
  already been proposed once, but resulted in the feedback that I need
  to go back and restructure stuff.  So I've been restructuring stuff.
  On the way I ran into brokenness (return code from the get_value()
  callback) and had to fix it.  Also, refactored generic GPIO to be
  simpler.

  Some of that is still waiting to trickle down from the subsystems all
  over the kernel that provide random gpio_chips, I've touched every
  single GPIO driver in the kernel now, oh man I didn't know I was
  responsible for so much...

  Apart from that we're churning along as usual.

  I took some effort to test and retest so it should merge nicely and we
  shook out a couple of bugs in -next.

  Infrastructural changes:

   - In struct gpio_chip, rename the .dev node to .parent to better
     reflect the fact that this is not the GPIO struct device
     abstraction.  We will add that soon so this would be totallt
     confusing.

   - It was noted that the driver .get_value() callbacks was sometimes
     reporting negative -ERR values to the gpiolib core, expecting them
     to be propagated to consumer gpiod_get_value() and gpio_get_value()
     calls.  This was not happening, so as there was a mess of drivers
     returning negative errors and some returning "anything else than
     zero" to indicate that a line was active.  As some would have bit
     31 set to indicate "line active" it clashed with negative error
     codes.  This is fixed by the largeish series clamping values in all
     drivers with !!value to [0,1] and then augmenting the code to
     propagate error codes to consumers.  (Includes some ACKed patches
     in other subsystems.)

   - Add a void *data pointer to struct gpio_chip.  The container_of()
     design pattern is indeed very nice, but we want to reform the
     struct gpio_chip to be a non-volative, stateless business, and keep
     states internal to the gpiolib to be able to hold on to the state
     when adding a proper userspace ABI (character device) further down
     the road.  To achieve this, drivers need a handle at the internal
     state that is not dependent on their struct gpio_chip() so we add
     gpiochip_add_data() and gpiochip_get_data() following the pattern
     of many other subsystems.  All the "use gpiochip data pointer"
     patches transforms drivers to this scheme.

   - The Generic GPIO chip header has been merged into the general
     <linux/gpio/driver.h> header, and the custom header for that
     removed.  Instead of having a separate mm_gpio_chip struct for
     these generic drivers, merge that into struct gpio_chip,
     simplifying the code and removing the need for separate and
     confusing includes.

  Misc improvements:

   - Stabilize the way GPIOs are looked up from the ACPI legacy
     specification.

   - Incremental driver features for PXA, PCA953X, Lantiq (patches from
     the OpenWRT community), RCAR, Zynq, PL061, 104-idi-48

  New drivers:

   - Add a GPIO chip to the ALSA SoC AC97 driver.

   - Add a new Broadcom NSP SoC driver (this lands in the pinctrl dir,
     but the branch is merged here too to account for infrastructural
     changes).

   - The sx150x driver now supports the sx1502"

* tag 'gpio-v4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (220 commits)
  gpio: generic: make bgpio_pdata always visible
  gpiolib: fix chip order in gpio list
  gpio: mpc8xxx: Do not use gpiochip_get_data() in mpc8xxx_gpio_save_regs()
  gpio: mm-lantiq: Do not use gpiochip_get_data() in ltq_mm_save_regs()
  gpio: brcmstb: Allow building driver for BMIPS_GENERIC
  gpio: brcmstb: Set endian flags for big-endian MIPS
  gpio: moxart: fix build regression
  gpio: xilinx: Do not use gpiochip_get_data() in xgpio_save_regs()
  leds: pca9532: use gpiochip data pointer
  leds: tca6507: use gpiochip data pointer
  hid: cp2112: use gpiochip data pointer
  bcma: gpio: use gpiochip data pointer
  avr32: gpio: use gpiochip data pointer
  video: fbdev: via: use gpiochip data pointer
  gpio: pch: Optimize pch_gpio_get()
  Revert "pinctrl: lantiq: Implement gpio_chip.to_irq"
  pinctrl: nsp-gpio: use gpiochip data pointer
  pinctrl: vt8500-wmt: use gpiochip data pointer
  pinctrl: exynos5440: use gpiochip data pointer
  pinctrl: at91-pio4: use gpiochip data pointer
  ...
2016-01-17 12:32:01 -08:00
Linus Torvalds
1c5ff2ab7b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input updates from Dmitry Torokhov:
 - new driver for eGalaxTouch serial touchscreen
 - new driver for TS-4800 touchscreen
 - an update for Goodix touchscreen driver
 - PS/2 mouse module was reworked to limit number of protocols we try on
   pass-through ports to speed up their detection time
 - wacom_w8001 touchscreen driver now reports pen and touch via separate
   instances of input devices
 - other driver changes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (42 commits)
  Input: elantech - mark protocols v2 and v3 as semi-mt
  Input: wacom_w8001 - drop use of ABS_MT_TOOL_TYPE
  Input: gpio-keys - fix check for disabling unsupported keys
  Input: omap-keypad - remove dead check
  Input: ti_am335x_tsc - fix HWPEN interrupt handling
  Input: omap-keypad - set tasklet data earlier
  Input: rohm_bu21023 - fix handling of retrying firmware update
  Input: ALPS - report v3 pinnacle trackstick device only if is present
  Input: ALPS - detect trackstick presence for v7 protocol
  Input: pcap_ts - use to_delayed_work
  Input: bma150 - constify bma150_cfg structure
  Input: i8042 - add Fujitsu Lifebook U745 to the nomux list
  Input: egalax_ts_serial - fix potential NULL dereference on error
  Input: uinput - sanity check on ff_effects_max and EV_FF
  Input: uinput - rework ABS validation
  Input: uinput - add new UINPUT_DEV_SETUP and UI_ABS_SETUP ioctl
  Input: goodix - use "inverted_[xy]" flags instead of "rotated_screen"
  Input: goodix - add axis swapping and axis inversion support
  Input: goodix - use goodix_i2c_write_u8 instead of i2c_master_send
  Input: goodix - add power management support
  ...
2016-01-13 11:14:05 -08:00
Christophe RICARD
52044723cd ACPI / gpio: Add irq_type when a GPIO is used as an interrupt
When a GPIO is used as an interrupt in ACPI, the irq_type was not
available for device driver.

Make available polarity and triggering information in acpi_find_gpio by
renaming acpi_gpio_info field active_low  to polarity and adding triggering
field (edge/level).

For sanity, in gpiolib.c replace info.active_low by
"info.polarity == GPIO_ACTIVE_LOW".

Set the irq_type if necessary in acpi_dev_gpio_irq_get.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-01-01 03:20:25 +01:00
Dmitry Torokhov
10cf4899f8 gpiolib: tighten up ACPI legacy gpio lookups
We should not fall back to the legacy unnamed gpio lookup style if the
driver requests gpios with different names, because we'll give out the same
gpio twice. Let's keep track of the names that were used for the device and
only do the fallback for the first name used.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-12-13 17:36:02 +01:00
Linus Walleij
29ab875b7b gpio: forward-declare enum gpiod_flags
This enum is used in the gpiolib.h header file, yet
<linux/gpio/consumer.h> is not included so plainly including this
file (and some drivers do) will raise compile problems.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-12-11 19:14:35 +01:00
Dmitry Torokhov
9c3c9bc9cc gpiolib: tighten up ACPI legacy gpio lookups
We should not fall back to the legacy unnamed gpio lookup style if the
driver requests gpios with different names, because we'll give out the same
gpio twice. Let's keep track of the names that were used for the device and
only do the fallback for the first name used.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-11-19 09:24:37 +01:00
Linus Torvalds
0d51ce9ca1 Power management and ACPI updates for v4.4-rc1
- ACPICA update to upstream revision 20150930 (Bob Moore, Lv Zheng).
 
    The most significant change is to allow the AML debugger to be
    built into the kernel.  On top of that there is an update related
    to the NFIT table (the ACPI persistent memory interface)
    and a few fixes and cleanups.
 
  - ACPI CPPC2 (Collaborative Processor Performance Control v2)
    support along with a cpufreq frontend (Ashwin Chaugule).
 
    This can only be enabled on ARM64 at this point.
 
  - New ACPI infrastructure for the early probing of IRQ chips and
    clock sources (Marc Zyngier).
 
  - Support for a new hierarchical properties extension of the ACPI
    _DSD (Device Specific Data) device configuration object allowing
    the kernel to handle hierarchical properties (provided by the
    platform firmware this way) automatically and make them available
    to device drivers via the generic device properties interface
    (Rafael Wysocki).
 
  - Generic device properties API extension to obtain an index of
    certain string value in an array of strings, along the lines of
    of_property_match_string(), but working for all of the supported
    firmware node types, and support for the "dma-names" device
    property based on it (Mika Westerberg).
 
  - ACPI core fix to parse the MADT (Multiple APIC Description Table)
    entries in the order expected by platform firmware (and mandated
    by the specification) to avoid confusion on systems with more than
    255 logical CPUs (Lukasz Anaczkowski).
 
  - Consolidation of the ACPI-based handling of PCI host bridges
    on x86 and ia64 (Jiang Liu).
 
  - ACPI core fixes to ensure that the correct IRQ number is used to
    represent the SCI (System Control Interrupt) in the cases when
    it has been re-mapped (Chen Yu).
 
  - New ACPI backlight quirk for Lenovo IdeaPad S405 (Hans de Goede).
 
  - ACPI EC driver fixes (Lv Zheng).
 
  - Assorted ACPI fixes and cleanups (Dan Carpenter, Insu Yun, Jiri
    Kosina, Rami Rosen, Rasmus Villemoes).
 
  - New mechanism in the PM core allowing drivers to check if the
    platform firmware is going to be involved in the upcoming system
    suspend or if it has been involved in the suspend the system is
    resuming from at the moment (Rafael Wysocki).
 
    This should allow drivers to optimize their suspend/resume
    handling in some cases and the changes include a couple of users
    of it (the i8042 input driver, PCI PM).
 
  - PCI PM fix to prevent runtime-suspended devices with PME enabled
    from being resumed during system suspend even if they aren't
    configured to wake up the system from sleep (Rafael Wysocki).
 
  - New mechanism to report the number of a wakeup IRQ that woke up
    the system from sleep last time (Alexandra Yates).
 
  - Removal of unused interfaces from the generic power domains
    framework and fixes related to latency measurements in that
    code (Ulf Hansson, Daniel Lezcano).
 
  - cpufreq core sysfs interface rework to make it handle CPUs that
    share performance scaling settings (represented by a common
    cpufreq policy object) more symmetrically (Viresh Kumar).
 
    This should help to simplify the CPU offline/online handling among
    other things.
 
  - cpufreq core fixes and cleanups (Viresh Kumar).
 
  - intel_pstate fixes related to the Turbo Activation Ratio (TAR)
    mechanism on client platforms which causes the turbo P-states
    range to vary depending on platform firmware settings (Srinivas
    Pandruvada).
 
  - intel_pstate sysfs interface fix (Prarit Bhargava).
 
  - Assorted cpufreq driver (imx, tegra20, powernv, integrator) fixes
    and cleanups (Bai Ping, Bartlomiej Zolnierkiewicz, Shilpasri G
    Bhat, Luis de Bethencourt).
 
  - cpuidle mvebu driver cleanups (Russell King).
 
  - OPP (Operating Performance Points) framework code reorganization
    to make it more maintainable (Viresh Kumar).
 
  - Intel Broxton support for the RAPL (Running Average Power Limits)
    power capping driver (Amy Wiles).
 
  - Assorted power management code fixes and cleanups (Dan Carpenter,
    Geert Uytterhoeven, Geliang Tang, Luis de Bethencourt, Rasmus
    Villemoes).
 
 /
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Merge tag 'pm+acpi-4.4-rc1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI updates from Rafael Wysocki:
 "Quite a new features are included this time.

  First off, the Collaborative Processor Performance Control interface
  (version 2) defined by ACPI will now be supported on ARM64 along with
  a cpufreq frontend for CPU performance scaling.

  Second, ACPI gets a new infrastructure for the early probing of IRQ
  chips and clock sources (along the lines of the existing similar
  mechanism for DT).

  Next, the ACPI core and the generic device properties API will now
  support a recently introduced hierarchical properties extension of the
  _DSD (Device Specific Data) ACPI device configuration object.  If the
  ACPI platform firmware uses that extension to organize device
  properties in a hierarchical way, the kernel will automatically handle
  it and make those properties available to device drivers via the
  generic device properties API.

  It also will be possible to build the ACPICA's AML interpreter
  debugger into the kernel now and use that to diagnose AML-related
  problems more efficiently.  In the future, this should make it
  possible to single-step AML execution and do similar things.
  Interesting stuff, although somewhat experimental at this point.

  Finally, the PM core gets a new mechanism that can be used by device
  drivers to distinguish between suspend-to-RAM (based on platform
  firmware support) and suspend-to-idle (or other variants of system
  suspend the platform firmware is not involved in) and possibly
  optimize their device suspend/resume handling accordingly.

  In addition to that, some existing features are re-organized quite
  substantially.

  First, the ACPI-based handling of PCI host bridges on x86 and ia64 is
  unified and the common code goes into the ACPI core (so as to reduce
  code duplication and eliminate non-essential differences between the
  two architectures in that area).

  Second, the Operating Performance Points (OPP) framework is
  reorganized to make the code easier to find and follow.

  Next, the cpufreq core's sysfs interface is reorganized to get rid of
  the "primary CPU" concept for configurations in which the same
  performance scaling settings are shared between multiple CPUs.

  Finally, some interfaces that aren't necessary any more are dropped
  from the generic power domains framework.

  On top of the above we have some minor extensions, cleanups and bug
  fixes in multiple places, as usual.

  Specifics:

   - ACPICA update to upstream revision 20150930 (Bob Moore, Lv Zheng).

     The most significant change is to allow the AML debugger to be
     built into the kernel.  On top of that there is an update related
     to the NFIT table (the ACPI persistent memory interface) and a few
     fixes and cleanups.

   - ACPI CPPC2 (Collaborative Processor Performance Control v2) support
     along with a cpufreq frontend (Ashwin Chaugule).

     This can only be enabled on ARM64 at this point.

   - New ACPI infrastructure for the early probing of IRQ chips and
     clock sources (Marc Zyngier).

   - Support for a new hierarchical properties extension of the ACPI
     _DSD (Device Specific Data) device configuration object allowing
     the kernel to handle hierarchical properties (provided by the
     platform firmware this way) automatically and make them available
     to device drivers via the generic device properties interface
     (Rafael Wysocki).

   - Generic device properties API extension to obtain an index of
     certain string value in an array of strings, along the lines of
     of_property_match_string(), but working for all of the supported
     firmware node types, and support for the "dma-names" device
     property based on it (Mika Westerberg).

   - ACPI core fix to parse the MADT (Multiple APIC Description Table)
     entries in the order expected by platform firmware (and mandated by
     the specification) to avoid confusion on systems with more than 255
     logical CPUs (Lukasz Anaczkowski).

   - Consolidation of the ACPI-based handling of PCI host bridges on x86
     and ia64 (Jiang Liu).

   - ACPI core fixes to ensure that the correct IRQ number is used to
     represent the SCI (System Control Interrupt) in the cases when it
     has been re-mapped (Chen Yu).

   - New ACPI backlight quirk for Lenovo IdeaPad S405 (Hans de Goede).

   - ACPI EC driver fixes (Lv Zheng).

   - Assorted ACPI fixes and cleanups (Dan Carpenter, Insu Yun, Jiri
     Kosina, Rami Rosen, Rasmus Villemoes).

   - New mechanism in the PM core allowing drivers to check if the
     platform firmware is going to be involved in the upcoming system
     suspend or if it has been involved in the suspend the system is
     resuming from at the moment (Rafael Wysocki).

     This should allow drivers to optimize their suspend/resume handling
     in some cases and the changes include a couple of users of it (the
     i8042 input driver, PCI PM).

   - PCI PM fix to prevent runtime-suspended devices with PME enabled
     from being resumed during system suspend even if they aren't
     configured to wake up the system from sleep (Rafael Wysocki).

   - New mechanism to report the number of a wakeup IRQ that woke up the
     system from sleep last time (Alexandra Yates).

   - Removal of unused interfaces from the generic power domains
     framework and fixes related to latency measurements in that code
     (Ulf Hansson, Daniel Lezcano).

   - cpufreq core sysfs interface rework to make it handle CPUs that
     share performance scaling settings (represented by a common cpufreq
     policy object) more symmetrically (Viresh Kumar).

     This should help to simplify the CPU offline/online handling among
     other things.

   - cpufreq core fixes and cleanups (Viresh Kumar).

   - intel_pstate fixes related to the Turbo Activation Ratio (TAR)
     mechanism on client platforms which causes the turbo P-states range
     to vary depending on platform firmware settings (Srinivas
     Pandruvada).

   - intel_pstate sysfs interface fix (Prarit Bhargava).

   - Assorted cpufreq driver (imx, tegra20, powernv, integrator) fixes
     and cleanups (Bai Ping, Bartlomiej Zolnierkiewicz, Shilpasri G
     Bhat, Luis de Bethencourt).

   - cpuidle mvebu driver cleanups (Russell King).

   - OPP (Operating Performance Points) framework code reorganization to
     make it more maintainable (Viresh Kumar).

   - Intel Broxton support for the RAPL (Running Average Power Limits)
     power capping driver (Amy Wiles).

   - Assorted power management code fixes and cleanups (Dan Carpenter,
     Geert Uytterhoeven, Geliang Tang, Luis de Bethencourt, Rasmus
     Villemoes)"

* tag 'pm+acpi-4.4-rc1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (108 commits)
  cpufreq: postfix policy directory with the first CPU in related_cpus
  cpufreq: create cpu/cpufreq/policyX directories
  cpufreq: remove cpufreq_sysfs_{create|remove}_file()
  cpufreq: create cpu/cpufreq at boot time
  cpufreq: Use cpumask_copy instead of cpumask_or to copy a mask
  cpufreq: ondemand: Drop unnecessary locks from update_sampling_rate()
  PM / Domains: Merge measurements for PM QoS device latencies
  PM / Domains: Don't measure ->start|stop() latency in system PM callbacks
  PM / clk: Fix broken build due to non-matching code and header #ifdefs
  ACPI / Documentation: add copy_dsdt to ACPI format options
  ACPI / sysfs: correctly check failing memory allocation
  ACPI / video: Add a quirk to force native backlight on Lenovo IdeaPad S405
  ACPI / CPPC: Fix potential memory leak
  ACPI / CPPC: signedness bug in register_pcc_channel()
  ACPI / PAD: power_saving_thread() is not freezable
  ACPI / PM: Fix incorrect wakeup IRQ setting during suspend-to-idle
  ACPI: Using correct irq when waiting for events
  ACPI: Use correct IRQ when uninstalling ACPI interrupt handler
  cpuidle: mvebu: disable the bind/unbind attributes and use builtin_platform_driver
  cpuidle: mvebu: clean up multiple platform drivers
  ...
2015-11-04 18:10:13 -08:00
Markus Pargmann
c0017ed719 gpio: Introduce gpio descriptor 'name'
The latest gpio hogging mechanism assigns each gpio a 'line-name' in the
devicetree. The 'name' field is different from the 'label' field.
'label' is only used for requested GPIOs to describe its current use by
driver or userspace.

The 'name' field describes the GPIO itself, not the use. This is most
likely identical to the label in the schematic on the GPIO line and
should help to find this particular GPIO.

This is equivalent to the gpiochip->names array. However names should be
stored in the GPIO descriptor. We will use gpiochip->names in the future
only as initializer for the GPIO descriptors for drivers that assign
GPIO names hardcoded. All other GPIO names will be parsed from DT and
directly assigned to the GPIO descriptor.

This patch adds a helper function to find gpio descriptors by name
instead of gpio number.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-09-24 10:48:51 -07:00
Rafael J. Wysocki
504a337499 ACPI / property: Extend device_get_next_child_node() to data-only nodes
Make device_get_next_child_node() work with ACPI data-only subnodes
introduced previously.

Namely, replace acpi_get_next_child() with acpi_get_next_subnode()
that can handle (and return) child device objects as well as child
data-only subnodes of the given device and modify the ACPI part
of the GPIO subsystem to handle data-only subnodes returned by it.

To that end, introduce acpi_node_get_gpiod() taking a struct
fwnode_handle pointer as the first argument.  That argument may
point to an ACPI device object as well as to a data-only subnode
and the function should do the right thing (ie. look for the matching
GPIO descriptor correctly) in either case.

Next, modify fwnode_get_named_gpiod() to use acpi_node_get_gpiod()
instead of acpi_get_gpiod_by_index() which automatically causes
devm_get_gpiod_from_child() to work with ACPI data-only subnodes
that may be returned by device_get_next_child_node() which in turn
is required by the users of that function (the gpio_keys_polled
and gpio-leds drivers).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
2015-09-15 01:47:34 +02:00
Johan Hovold
cef1717b7f gpio: sysfs: move irq trigger flags to class-device data
Move irq trigger flags, which as sysfs-interface specific, to the class
device data.

This avoids accessing the gpio-descriptor flags field using non-atomic
operations without any locking, and allows for a more clear separation
of the sysfs interface from gpiolib core.

Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12 10:47:57 +02:00
Johan Hovold
427fdeef50 gpio: sysfs: remove FLAG_SYSFS_DIR
Remove FLAG_SYSFS_DIR, which is sysfs-interface specific, and store it
in the class-device data instead.

Note that the flag is only used during export.

Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12 10:47:52 +02:00
Johan Hovold
a08f5c21f4 gpio: sysfs: clean up interrupt-interface implementation
Store the value sysfs entry in the gpiod data rather than in a global
table accessed through an index stored in the overloaded gpio-descriptor
flag field.

Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12 10:47:19 +02:00
Johan Hovold
426577bd88 gpio: sysfs: rename gpiochip registration functions
Rename the gpio-chip export/unexport functions to the more descriptive
names gpiochip_sysfs_register and gpiochip_sysfs_unregister.

Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12 10:46:49 +02:00
Linus Torvalds
510965dd4a This is the bulk of GPIO changes for the v4.1 development
cycle:
 
 - A new GPIO hogging mechanism has been added. This can
   be used on boards that want to drive some GPIO line high,
   low, or set it as input on boot and then never touch it
   again. For some embedded systems this is bliss and
   simplifies things to a great extent.
 
 - Some API cleanup and closure: gpiod_get_array() and
   gpiod_put_array() has been added to get and put GPIOs
   in bulk as was possible with the non-descriptor API.
 
 - Encapsulate cross-calls to the pin control subsystem in
   <linux/gpio/driver.h>. Now this should be the only header
   any GPIO driver needs to include or something is wrong.
   Cleanups restricting drivers to this include are welcomed
   if tested.
 
 - Sort the GPIO Kconfig and split it into submenus, as
   it was becoming and unstructured, illogical and
   unnavigatable mess. I hope this is easier to follow.
   Menus that require a certain subsystem like I2C can
   now be hidden nicely for example, still working on
   others.
 
 - New drivers:
 
     - New driver for the Altera Soft GPIO.
 
     - The F7188x driver now handles the F71869 and
       F71869A variants.
 
     - The MIPS Loongson driver has been moved to
       drivers/gpio for consolidation and cleanup.
 
 - Cleanups:
 
    - The MAX732x is converted to use the GPIOLIB_IRQCHIP
      infrastructure.
 
    - The PCF857x is converted to use the GPIOLIB_IRQCHIP
      infrastructure.
 
    - Radical cleanup of the OMAP driver.
 
 - Misc:
 
    - Enable the DWAPB GPIO for all architectures. This is
      a "hard IP" block from Synopsys which has started to
      turn up in so diverse architectures as X86 Quark, ARC
      and a slew of ARM systems. So even though it's not an
      expander, it's generic enough to be available for all.
 
    - We add a mock GPIO on Crystalcove PMIC after a long
      discussion with Daniel Vetter et al, tracing back to
      the shootout at the kernel summit where DRM drivers
      and sub-componentization was discussed. In this case
      a mock GPIO is assumed to be the best compromise
      gaining some reuse of infrastructure without making
      DRM drivers overly complex at the same time. Let's
      see.
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Merge tag 'gpio-v4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v4.1 development cycle:

   - A new GPIO hogging mechanism has been added.  This can be used on
     boards that want to drive some GPIO line high, low, or set it as
     input on boot and then never touch it again.  For some embedded
     systems this is bliss and simplifies things to a great extent.

   - Some API cleanup and closure: gpiod_get_array() and
     gpiod_put_array() has been added to get and put GPIOs in bulk as
     was possible with the non-descriptor API.

   - Encapsulate cross-calls to the pin control subsystem in
     <linux/gpio/driver.h>.  Now this should be the only header any GPIO
     driver needs to include or something is wrong.  Cleanups
     restricting drivers to this include are welcomed if tested.

   - Sort the GPIO Kconfig and split it into submenus, as it was
     becoming and unstructured, illogical and unnavigatable mess.  I
     hope this is easier to follow.  Menus that require a certain
     subsystem like I2C can now be hidden nicely for example, still
     working on others.

   - New drivers:

       - New driver for the Altera Soft GPIO.

       - The F7188x driver now handles the F71869 and F71869A variants.

       - The MIPS Loongson driver has been moved to drivers/gpio for
         consolidation and cleanup.

   - Cleanups:

       - The MAX732x is converted to use the GPIOLIB_IRQCHIP
         infrastructure.

       - The PCF857x is converted to use the GPIOLIB_IRQCHIP
         infrastructure.

       - Radical cleanup of the OMAP driver.

   - Misc:

       - Enable the DWAPB GPIO for all architectures.  This is a "hard
         IP" block from Synopsys which has started to turn up in so
         diverse architectures as X86 Quark, ARC and a slew of ARM
         systems.  So even though it's not an expander, it's generic
         enough to be available for all.

       - We add a mock GPIO on Crystalcove PMIC after a long discussion
         with Daniel Vetter et al, tracing back to the shootout at the
         kernel summit where DRM drivers and sub-componentization was
         discussed.  In this case a mock GPIO is assumed to be the best
         compromise gaining some reuse of infrastructure without making
         DRM drivers overly complex at the same time.  Let's see"

* tag 'gpio-v4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (62 commits)
  Revert "gpio: sch: use uapi/linux/pci_ids.h directly"
  gpio: dwapb: remove dependencies
  gpio: dwapb: enable for ARC
  gpio: removing kfree remove functionality
  gpio: mvebu: Fix mask/unmask managment per irq chip type
  gpio: split GPIO drivers in submenus
  gpio: move MFD GPIO drivers under their own comment
  gpio: move BCM Kona Kconfig option
  gpio: arrange SPI Kconfig symbols alphabetically
  gpio: arrange PCI GPIO controllers alphabetically
  gpio: arrange I2C Kconfig symbols alphabetically
  gpio: arrange Kconfig symbols alphabetically
  gpio: ich: Implement get_direction function
  gpio: use (!foo) instead of (foo == NULL)
  gpio: arizona: drop owner assignment from platform_drivers
  gpio: max7300: remove 'ret' variable
  gpio: use devm_kzalloc
  gpio: sch: use uapi/linux/pci_ids.h directly
  gpio: x-gene: fix devm_ioremap_resource() check
  gpio: loongson: Add Loongson-3A/3B GPIO driver support
  ...
2015-04-18 08:22:10 -04:00
Rafael J. Wysocki
ce793486e2 driver core / ACPI: Represent ACPI companions using fwnode_handle
Now that we have struct fwnode_handle, we can use that to point to
ACPI companions from struct device objects instead of pointing to
struct acpi_device directly.

There are two benefits from that.  First, the somewhat ugly and
hackish struct acpi_dev_node can be dropped and, second, the same
struct fwnode_handle pointer can be used in the future to point
to other (non-ACPI) firmware device node types.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Grant Likely <grant.likely@linaro.org>
2015-03-16 23:49:03 +01:00
Rojhalat Ibrahim
6685852732 gpiolib: add gpiod_get_array and gpiod_put_array functions
Introduce new functions for conveniently obtaining and disposing of
an entire array of GPIOs with one function call.

ACPI parts tested by Mika Westerberg, DT parts tested by Rojhalat
Ibrahim.

Change log:
v5: move the ACPI functions to gpiolib-acpi.c
v4: - use shorter names for members of struct gpio_descs
    - rename lut_gpio_count to platform_gpio_count for clarity
    - add check for successful memory allocation
    - use ERR_CAST()
v3: - rebase on current linux-gpio devel branch
    - fix ACPI GPIO counting
    - allow for zero-sized arrays
    - make the flags argument mandatory for the new functions
    - clarify documentation
v2: change interface

Suggested-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Rojhalat Ibrahim <imr@rtschenk.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-05 09:52:28 +01:00
Rojhalat Ibrahim
7f2e553a71 gpiolib: define gpio suffixes globally
Avoid multiple identical definitions of the gpio suffix strings by putting
them into a global constant array.

Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-05 09:48:51 +01:00
Benoit Parrot
f625d46017 gpio: add GPIO hogging mechanism
Based on Boris Brezillion's work this is a reworked patch
of his initial GPIO hogging mechanism.
This patch provides a way to initially configure specific GPIO
when the GPIO controller is probed.

The actual DT scanning to collect the GPIO specific data is performed
as part of gpiochip_add().

The purpose of this is to allow specific GPIOs to be configured
without any driver specific code.
This is particularly useful because board design are getting
increasingly complex and given SoC pins can now have more
than 10 mux values, a lot of connections are now dependent on
external IO muxes to switch various modes.

Specific drivers should not necessarily need to be aware of
what accounts to a specific board implementation. This board level
"description" should be best kept as part of the dts file.

Signed-off-by: Benoit Parrot <bparrot@ti.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-04 11:09:00 +01:00
Johan Hovold
ebbeba120a gpio: sysfs: fix gpio attribute-creation race
Fix attribute-creation race with userspace by using the default group
to create also the contingent gpio device attributes.

Fixes: d8f388d8dc ("gpio: sysfs interface")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-01-15 17:20:56 +01:00
Mika Westerberg
0d9a693cc8 gpio / ACPI: Add support for _DSD device properties
With release of ACPI 5.1 and _DSD method we can finally name GPIOs (and
other things as well) returned by _CRS. Previously we were only able to
use integer index to find the corresponding GPIO, which is pretty error
prone if the order changes.

With _DSD we can now query GPIOs using name instead of an integer index,
like the below example shows:

  // Bluetooth device with reset and shutdown GPIOs
  Device (BTH)
  {
      Name (_HID, ...)

      Name (_CRS, ResourceTemplate ()
      {
          GpioIo (Exclusive, PullUp, 0, 0, IoRestrictionInputOnly,
                  "\\_SB.GPO0", 0, ResourceConsumer) {15}
          GpioIo (Exclusive, PullUp, 0, 0, IoRestrictionInputOnly,
                  "\\_SB.GPO0", 0, ResourceConsumer) {27, 31}
      })

      Name (_DSD, Package ()
      {
          ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
          Package ()
	  {
              Package () {"reset-gpio", Package() {^BTH, 1, 1, 0 }},
              Package () {"shutdown-gpio", Package() {^BTH, 0, 0, 0 }},
          }
      })
  }

The format of the supported GPIO property is:

  Package () { "name", Package () { ref, index, pin, active_low }}

  ref - The device that has _CRS containing GpioIo()/GpioInt() resources,
        typically this is the device itself (BTH in our case).
  index - Index of the GpioIo()/GpioInt() resource in _CRS starting from zero.
  pin - Pin in the GpioIo()/GpioInt() resource. Typically this is zero.
  active_low - If 1 the GPIO is marked as active_low.

Since ACPI GpioIo() resource does not have field saying whether it is
active low or high, the "active_low" argument can be used here. Setting
it to 1 marks the GPIO as active low.

In our Bluetooth example the "reset-gpio" refers to the second GpioIo()
resource, second pin in that resource with the GPIO number of 31.

This patch implements necessary support to gpiolib for extracting GPIOs
using _DSD device properties.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-04 21:58:22 +01:00
Mika Westerberg
afa82fab5e gpio / ACPI: Move event handling registration to gpiolib irqchip helpers
Since now we have irqchip helpers that the GPIO chip drivers are supposed
to use if possible, we can move the registration of ACPI events to happen
in these helpers. This seems to be more natural place and might encourage
GPIO chip driver writers to take advantage of the irqchip helpers.

We make the functions available to GPIO chip drivers via private gpiolib.h,
just in case generic irqchip helpers are not suitable.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-28 12:23:57 +02:00
Guenter Roeck
f7d4ad98fd gpiolib: Export gpiochip_request_own_desc and gpiochip_free_own_desc
Both functions were introduced to let gpio drivers request their own
gpio pins. Without exporting the functions, this can however only be
used by gpio drivers built into the kernel.

Secondary impact is that the functions can not currently be used by
platform initialization code associated with the gpio-pca953x driver.
This code permits auto-export of gpio pins through platform data, but
if this functionality is used, the module can no longer be unloaded due
to the problem solved with the introduction of gpiochip_request_own_desc
and gpiochip_free_own_desc.

Export both function so they can be used from modules and from
platform initialization code.

Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-24 10:25:00 +02:00
Alexandre Courbot
1bd6b601fe gpio: make gpiochip_get_desc() gpiolib-private
As GPIO descriptors are not going to remain unique anymore, having this
function public is not safe. Restrain its use to gpiolib since we have
no user outside of it.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-23 17:41:12 +02:00
Alexandre Courbot
0eb4c6c267 gpio: move sysfs support to its own file
sysfs support is currently entangled within the core GPIO support, while
it should relly just be a (privileged) user of the integer GPIO API.
This patch is a first step towards making the gpiolib code more readable
by splitting it into logical parts.

Move all sysfs support to their own source file, and share static
members of gpiolib that need to be in the private gpiolib.h file. In
the future we will want to put some of them back into gpiolib.c, but this
first patch let us at least identify them.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-09 12:22:57 +02:00
Alexandre Courbot
f01d907582 gpio: make of_get_named_gpiod_flags() private
of_get_named_gpiod_flags() is visible and directly usable by GPIO
consumers, but it really should not as the gpiod interface relies
on the simpler gpiod_get() to provide properly-configured GPIOs.

of_get_named_gpiod_flags() is just used internally by gpiolib to
implement gpiod_get(), and by the old of_get_named_gpio_flags()
function, therefore it makes sense to make it gpiolib-private.

As a side-effect, the unused (and unneeded) of_get_gpiod_flags()
inline function is also removed, and of_get_named_gpio_flags() is moved
from a static inline function to a regular one in gpiolib-of.c

This results in all references to gpiod_* functions in of_gpio.h being
gone, which is the way it should be since this file is part of the old
integer GPIO interface.

Changes since v1:
- Fixed compilation error when CONFIG_OF_GPIO is not defined
- Fixed warning due to of_gpio_flags enum not being declared
  in private gpiolib.h header

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-05-21 11:14:46 +02:00
Mika Westerberg
77c2d7929d gpiolib: Allow GPIO chips to request their own GPIOs
Sometimes it is useful to allow GPIO chips themselves to request GPIOs they
own through gpiolib API. One use case is ACPI ASL code that should be able
to toggle GPIOs through GPIO operation regions.

We can't use gpio_request() because it will pin the module to the kernel
forever (it calls try_module_get()). To solve this we move module refcount
manipulation to gpiod_request() and let __gpiod_request() handle the actual
request. This changes the sequence a bit as now try_module_get() is called
outside of gpio_lock (I think this is safe, try_module_get() handles
serialization it needs already).

Then we provide gpiolib internal functions gpiochip_request/free_own_desc()
that do the same as gpio_request() but don't manipulate module refrence
count. This allows the GPIO chip driver to request and free descriptors it
owns without being pinned to the kernel forever.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-03-13 10:32:18 +01:00
Mika Westerberg
5ccff85276 gpio / ACPI: get rid of acpi_gpio.h
Now that all users of acpi_gpio.h have been moved to use either the GPIO
descriptor interface or to the internal gpiolib.h we can get rid of
acpi_gpio.h entirely.

Once this is done the only interface to get GPIOs to drivers enumerated
from ACPI namespace is the descriptor based interface.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-01-08 15:07:28 +01:00
Mika Westerberg
664e3e5ac6 gpio / ACPI: register to ACPI events automatically
Instead of asking each driver to register to ACPI events we can just call
acpi_gpiochip_register_interrupts() for each chip that has an ACPI handle.
The function checks chip->to_irq and if it is set to NULL (a GPIO driver
that doesn't do interrupts) the function does nothing.

We also add the a new header drivers/gpio/gpiolib.h that is used for
functions internal to gpiolib and add ACPI GPIO chip registering functions
to that header.

Once that is done we can remove call to acpi_gpiochip_register_interrupts()
from its only user, pinctrl-baytrail.c

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-01-08 15:07:28 +01:00