Commit graph

24 commits

Author SHA1 Message Date
Linus Torvalds
f01603979a gpio updates for v6.1-rc1
New drivers:
 - add a new driver for the IMX System Controller Unit GPIOs
 
 GPIO core:
 - add fdinfo output for the GPIO character device file descriptors (allows
   user-space to determine which processes own which GPIO lines)
 - improvements to OF GPIO code
 - new quirk for Asus UM325UAZ in gpiolib-acpi
 - new quirk for Freescale SPI in gpiolib-of
 
 Driver improvements:
 - add a new macro that reduces the amount of boilerplate code in ISA drivers
   and use it in relevant drivers
 - support two new models in gpio-pca953x
 - support new model in gpio-f7188x
 - convert more drivers to use immutable irq chips
 - other minor tweaks
 
 Device-tree bindings:
 - add DT bindings for gpio-imx-scu
 - convert Xilinx GPIO bindings to YAML
 - reference the properties from the SPI peripheral device-tree bindings
   instead of providing custom ones in the GPIO controller document
 - add parsing of GPIO hog nodes to the DT bindings for gpio-mpfs-gpio
 - relax the node name requirements in gpio-stmpe
 - add new models for gpio-rcar and gpio-pxa95xx
 - add a new vendor prefix: Diodes (for Diodes, Inc.)
 
 Misc:
 - pulled in the immutable branch from the x86 platform drivers tree including
   support for a new simatic board that depends on GPIO changes
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Merge tag 'gpio-updates-for-v6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux

Pull gpio updates from Bartosz Golaszewski:
 "We have a single new driver, support for a bunch of new models,
  improvements in drivers and core gpiolib code as well device-tree
  bindings changes.

  Summary:

  New driver:
   - IMX System Controller Unit GPIOs

  GPIO core:
   - add fdinfo output for the GPIO character device file descriptors
     (allows user-space to determine which processes own which GPIO
     lines)
   - improvements to OF GPIO code
   - new quirk for Asus UM325UAZ in gpiolib-acpi
   - new quirk for Freescale SPI in gpiolib-of

  Driver improvements:
   - add a new macro that reduces the amount of boilerplate code in ISA
     drivers and use it in relevant drivers
   - support two new models in gpio-pca953x
   - support new model in gpio-f7188x
   - convert more drivers to use immutable irq chips
   - other minor tweaks

  Device-tree bindings:
   - add DT bindings for gpio-imx-scu
   - convert Xilinx GPIO bindings to YAML
   - reference the properties from the SPI peripheral device-tree
     bindings instead of providing custom ones in the GPIO controller
     document
   - add parsing of GPIO hog nodes to the DT bindings for gpio-mpfs-gpio
   - relax the node name requirements in gpio-stmpe
   - add new models for gpio-rcar and gpio-pxa95xx
   - add a new vendor prefix: Diodes (for Diodes, Inc.)

  Misc:
   - pulled in the immutable branch from the x86 platform drivers tree
     including support for a new simatic board that depends on GPIO
     changes"

* tag 'gpio-updates-for-v6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (36 commits)
  gpio: tc3589x: Make irqchip immutable
  gpiolib: cdev: add fdinfo output for line request file descriptors
  gpio: twl4030: Reorder functions which allows to drop a forward declaraion
  gpiolib: fix OOB access in quirk callbacks
  gpiolib: of: factor out conversion from OF flags
  gpiolib: rework quirk handling in of_find_gpio()
  gpiolib: of: make Freescale SPI quirk similar to all others
  gpiolib: of: do not ignore requested index when applying quirks
  gpio: ws16c48: Ensure number of irq matches number of base
  gpio: 104-idio-16: Ensure number of irq matches number of base
  gpio: 104-idi-48: Ensure number of irq matches number of base
  gpio: 104-dio-48e: Ensure number of irq matches number of base
  counter: 104-quad-8: Ensure number of irq matches number of base
  isa: Introduce the module_isa_driver_with_irq helper macro
  gpio: pca953x: Add support for PCAL6534
  gpio: pca953x: Swap if statements to save later complexity
  gpio: pca953x: Fix pca953x_gpio_set_pull_up_down()
  dt-bindings: gpio: pca95xx: add entry for pcal6534 and PI4IOE5V6534Q
  dt-bindings: vendor-prefixes: add Diodes
  gpio: mt7621: Switch to use platform_get_irq() function
  ...
2022-10-08 09:46:29 -07:00
William Breathitt Gray
c95671a3e7 gpio: ws16c48: Ensure number of irq matches number of base
The ws16c48 module calls devm_request_irq() for each device. If the
number of irq passed to the module does not match the number of base, a
default value of 0 is passed to devm_request_irq(). IRQ 0 is probably
not what the user wants, so utilize the module_isa_driver_with_irq macro
to ensure the number of irq matches the number of base.

Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2022-09-15 10:29:12 +02:00
William Breathitt Gray
6890381720 gpio: ws16c48: Make irq_chip immutable
Kernel warns about mutable irq_chips:

    "not an immutable chip, please consider fixing!"

Make the struct irq_chip const, flag it as IRQCHIP_IMMUTABLE, add the
new helper functions, and call the appropriate gpiolib functions.

Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2022-09-03 22:56:34 +02:00
William Breathitt Gray
2c05a0f29f gpio: ws16c48: Implement and utilize register structures
Reduce magic numbers and improve code readability by implementing and
utilizing named register data structures.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Paul Demetrotion <pdemetrotion@winsystems.com>
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2022-07-20 17:44:04 +02:00
William Breathitt Gray
5561a2b086 gpio: ws16c48: Utilize iomap interface
This driver doesn't need to access I/O ports directly via inb()/outb()
and friends. This patch abstracts such access by calling ioport_map()
to enable the use of more typical ioread8()/iowrite8() I/O memory
accessor calls.

Suggested-by: David Laight <David.Laight@ACULAB.COM>
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2022-05-14 14:57:12 +02:00
Marc Zyngier
dbd1c54fc8 gpio: Bulk conversion to generic_handle_domain_irq()
Wherever possible, replace constructs that match either
generic_handle_irq(irq_find_mapping()) or
generic_handle_irq(irq_linear_revmap()) to a single call to
generic_handle_domain_irq().

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-08-12 11:39:38 +01:00
Linus Walleij
fceb7ab385 gpio: ws16c48: Use irqchip template
This makes the driver use the irqchip template to assign
properties to the gpio_irq_chip instead of using the
explicit call to gpiochip_irqchip_add().

The irqchip is instead added while adding the gpiochip.
Also move the IRQ initialization to the special .init_hw()
callback.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Link: https://lore.kernel.org/r/20200722101938.151265-1-linus.walleij@linaro.org
2020-07-23 15:08:55 +02:00
William Breathitt Gray
acebb82fe9 gpio: ws16c48: utilize for_each_set_clump8 macro
Replace verbose implementation in get_multiple/set_multiple callbacks
with for_each_set_clump8 macro to simplify code and improve clarity.

Link: http://lkml.kernel.org/r/7a0d2c964e7f2d289b16c63ff6b06fc1f4c50d4d.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-04 19:44:12 -08:00
Matti Vaittinen
e42615ec23 gpio: Use new GPIO_LINE_DIRECTION
It's hard for occasional GPIO code reader/writer to know if values 0/1
equal to IN or OUT. Use defined GPIO_LINE_DIRECTION_IN and
GPIO_LINE_DIRECTION_OUT to help them out.

NOTE - for gpio-amd-fch and gpio-bd9571mwv:
This commit also changes the return value for direction get to equal 1
for direction INPUT. Prior this commit these drivers might have
returned some other positive value but 1 for INPUT.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Acked-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-11-07 09:27:48 +01:00
Thomas Gleixner
1802d0beec treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 655 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:41 -07:00
William Breathitt Gray
7a702691d0 gpio: ws16c48: Mask read inputs for get_multiple
This patch masks the read inputs with the word mask in order to ensure
only requested input states are returned in the bits array.

Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-11-05 08:54:42 +01:00
William Breathitt Gray
a8ff510dbc gpio: ws16c48: Implement get_multiple callback
The WinSystems WS16C48 device provides 48 lines of digital I/O accessed
via six 8-bit ports. Since eight input lines are acquired on a single
port input read, the WS16C48 GPIO driver may improve multiple input
reads by utilizing a get_multiple callback. This patch implements the
ws16c48_gpio_get_multiple function which serves as the respective
get_multiple callback.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-26 10:28:19 +02:00
Thierry Reding
f0fbe7bce7 gpio: Move irqdomain into struct gpio_irq_chip
In order to consolidate the multiple ways to associate an IRQ chip with
a GPIO chip, move more fields into the new struct gpio_irq_chip.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-11-08 14:06:21 +01:00
Linus Torvalds
291b38a756 Annotation of module parameters that specify device settings
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Merge tag 'hwparam-20170420' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull hw lockdown support from David Howells:
 "Annotation of module parameters that configure hardware resources
  including ioports, iomem addresses, irq lines and dma channels.

  This allows a future patch to prohibit the use of such module
  parameters to prevent that hardware from being abused to gain access
  to the running kernel image as part of locking the kernel down under
  UEFI secure boot conditions.

  Annotations are made by changing:

        module_param(n, t, p)
        module_param_named(n, v, t, p)
        module_param_array(n, t, m, p)

  to:

        module_param_hw(n, t, hwtype, p)
        module_param_hw_named(n, v, t, hwtype, p)
        module_param_hw_array(n, t, hwtype, m, p)

  where the module parameter refers to a hardware setting

  hwtype specifies the type of the resource being configured. This can
  be one of:

        ioport          Module parameter configures an I/O port
        iomem           Module parameter configures an I/O mem address
        ioport_or_iomem Module parameter could be either (runtime set)
        irq             Module parameter configures an I/O port
        dma             Module parameter configures a DMA channel
        dma_addr        Module parameter configures a DMA buffer address
        other           Module parameter configures some other value

  Note that the hwtype is compile checked, but not currently stored (the
  lockdown code probably won't require it). It is, however, there for
  future use.

  A bonus is that the hwtype can also be used for grepping.

  The intention is for the kernel to ignore or reject attempts to set
  annotated module parameters if lockdown is enabled. This applies to
  options passed on the boot command line, passed to insmod/modprobe or
  direct twiddling in /sys/module/ parameter files.

  The module initialisation then needs to handle the parameter not being
  set, by (1) giving an error, (2) probing for a value or (3) using a
  reasonable default.

  What I can't do is just reject a module out of hand because it may
  take a hardware setting in the module parameters. Some important
  modules, some ipmi stuff for instance, both probe for hardware and
  allow hardware to be manually specified; if the driver is aborts with
  any error, you don't get any ipmi hardware.

  Further, trying to do this entirely in the module initialisation code
  doesn't protect against sysfs twiddling.

  [!] Note that in and of itself, this series of patches should have no
      effect on the the size of the kernel or code execution - that is
      left to a patch in the next series to effect. It does mark
      annotated kernel parameters with a KERNEL_PARAM_FL_HWPARAM flag in
      an already existing field"

* tag 'hwparam-20170420' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (38 commits)
  Annotate hardware config module parameters in sound/pci/
  Annotate hardware config module parameters in sound/oss/
  Annotate hardware config module parameters in sound/isa/
  Annotate hardware config module parameters in sound/drivers/
  Annotate hardware config module parameters in fs/pstore/
  Annotate hardware config module parameters in drivers/watchdog/
  Annotate hardware config module parameters in drivers/video/
  Annotate hardware config module parameters in drivers/tty/
  Annotate hardware config module parameters in drivers/staging/vme/
  Annotate hardware config module parameters in drivers/staging/speakup/
  Annotate hardware config module parameters in drivers/staging/media/
  Annotate hardware config module parameters in drivers/scsi/
  Annotate hardware config module parameters in drivers/pcmcia/
  Annotate hardware config module parameters in drivers/pci/hotplug/
  Annotate hardware config module parameters in drivers/parport/
  Annotate hardware config module parameters in drivers/net/wireless/
  Annotate hardware config module parameters in drivers/net/wan/
  Annotate hardware config module parameters in drivers/net/irda/
  Annotate hardware config module parameters in drivers/net/hamradio/
  Annotate hardware config module parameters in drivers/net/ethernet/
  ...
2017-05-10 19:13:03 -07:00
David Howells
d759f90679 Annotate hardware config module parameters in drivers/gpio/
When the kernel is running in secure boot mode, we lock down the kernel to
prevent userspace from modifying the running kernel image.  Whilst this
includes prohibiting access to things like /dev/mem, it must also prevent
access by means of configuring driver modules in such a way as to cause a
device to access or modify the kernel image.

To this end, annotate module_param* statements that refer to hardware
configuration and indicate for future reference what type of parameter they
specify.  The parameter parser in the core sees this information and can
skip such parameters with an error message if the kernel is locked down.
The module initialisation then runs as normal, but just sees whatever the
default values for those parameters is.

Note that we do still need to do the module initialisation because some
drivers have viable defaults set in case parameters aren't specified and
some drivers support automatic configuration (e.g. PNP or PCI) in addition
to manually coded parameters.

This patch annotates drivers in drivers/gpio/.

Suggested-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
cc: Alexandre Courbot <gnurou@gmail.com>
cc: linux-gpio@vger.kernel.org
2017-04-20 12:02:32 +01:00
Julia Cartwright
a0a584f0e9 gpio: ws16c48: make use of raw_spinlock variants
The ws16c48 gpio driver currently implements an irq_chip for handling
interrupts; due to how irq_chip handling is done, it's necessary for the
irq_chip methods to be invoked from hardirq context, even on a a
real-time kernel.  Because the spinlock_t type becomes a "sleeping"
spinlock w/ RT kernels, it is not suitable to be used with irq_chips.

A quick audit of the operations under the lock reveal that they do only
minimal, bounded work, and are therefore safe to do under a raw spinlock.

Signed-off-by: Julia Cartwright <julia@ni.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-03-16 21:52:09 +01:00
William Breathitt Gray
5238f60feb gpio: ws16c48: Add support for GPIO names
This patch sets the gpio_chip names option with an array of GPIO line
names that match the manual documentation for the WinSystems WS16C48.
This should make it easier for users to identify which GPIO line
corresponds to a respective GPIO pin on the device.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-02-01 16:06:17 +01:00
William Breathitt Gray
9e1b487bb4 gpio: ws16c48: Remove unnecessary driver_data set
Setting driver_data was necessary to access private data in the
ws16c48_remove function. Now that the ws16c48_remove function is gone,
driver_data is no longer used. This patch removes the relevant code.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-02-01 15:59:21 +01:00
William Breathitt Gray
b4cad1bc5f gpio: ws16c48: Utilize devm_ functions in driver probe callback
The devm_ resource manager functions allow memory to be automatically
released when a device is unbound. This patch takes advantage of the
resource manager functions and replaces the gpiochip_add_data call and
request_irq call with the devm_gpiochip_add_data call and
devm_request_irq call respectively. In addition, the ws16c48_remove
function has been removed as no longer necessary due to the use of the
relevant devm_ resource manager functions.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-26 15:56:30 +01:00
William Breathitt Gray
99c8ac957e gpio: ws16c48: Add set_multiple callback function support
The WinSystems WS16C48 provides registers where 8 lines of GPIO may be
set at a time. This patch add support for the set_multiple callback
function, thus allowing multiple GPIO output lines to be set more
efficiently in groups.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-26 10:57:39 +01:00
William Breathitt Gray
cc736607c8 gpio: ws16c48: Utilize the ISA bus driver
The WinSystems WS16C48 communicates via the ISA bus. As such, it is more
appropriate to use the ISA bus driver over the platform driver to
control the WinSystems WS16C48 GPIO driver.

This patch also adds support for multiple devices via the base and irq
module array parameters. Each element of the base array corresponds to a
discrete device; each element of the irq array corresponds to the
respective device addressed in the respective base array element.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-02 09:32:04 -07:00
William Breathitt Gray
148ad68b3d gpio: ws16c48: Use devm_request_region
By the time request_region is called in the WinSystems WS16C48 GPIO
driver, a corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-16 00:19:54 +01:00
William Breathitt Gray
22aeddb58d gpio: misc: Pass correct license string to MODULE_LICENSE
The GPIO driver copyright boilerplate lacks the "or
later" verbiage regarding GPL compliant distribution. The MODULE_LICENSE
string should reflect the actual copyright license terms used.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-16 00:19:50 +01:00
William Breathitt Gray
9c26df9b27 gpio: Add GPIO support for the WinSystems WS16C48
The WinSystems WS16C48 device provides 48 lines of digital I/O. In
addition, the first 24 lines may be used for interrupt-handled edge
detection; rising edge detection and falling edge detection are
supported.

This driver provides GPIO and IRQ support for these 48 channels of
digital I/O. The base port address for the device may be configured via
the ws16c48_base module parameter. The interrupt line number for the
device may be configured via the ws16c48_irq module parameter.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-01-28 09:45:23 +01:00