The regmap API supports IO port accessors so we can take advantage of
regmap abstractions rather than handling access to the device registers
directly in the driver. The 104-dio-48e module is migrated to the new
i8255 library interface leveraging the gpio-regmap API.
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
The regmap API supports IO port accessors so we can take advantage of
regmap abstractions rather than handling access to the device registers
directly in the driver.
For the 104-dio-48e we have the following IRQ registers (0xB and 0xF):
Base Address +B (Write): Enable Interrupt
Base Address +B (Read): Disable Interrupt
Base Address +F (Read/Write): Clear Interrupt
Any write to 0xB will enable interrupts, while any read will disable
interrupts. Interrupts are cleared by a write to 0xF. There's no IRQ
status register, so software has to assume that if an interrupt is
raised then it was for the 104-DIO-48E device.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
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
...
The 104-dio-48e 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>
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>
Reduce magic numbers and improve code readability by implementing and
utilizing named register data structures. The 104-DIO-48E device
features an Intel 8255 compatible GPIO interface, so the i8255 GPIO
module is selected and utilized as well.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: John Hentges <jhentges@accesio.com>
Cc: Jay Dolan <jay.dolan@accesio.com>
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
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>
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>
Fixed multiple bare uses of 'unsigned' without 'int'.
Fixed space around "*" operator.
Fixed function parameter alignment to opening parenthesis.
Reported by checkpatch.
Signed-off-by: Barney Goette <barneygoette@gmail.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
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/20200722103915.162156-1-linus.walleij@linaro.org
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>
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>
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>
Don't populate the const read-only array 'ports' on the stack but instead
make it static. Makes the object code smaller by over 100 buytes:
Before:
text data bss dec hex filename
10959 4952 832 16743 4167 drivers/gpio/gpio-104-dio-48e.o
After:
text data bss dec hex filename
10790 5008 832 16630 40f6 drivers/gpio/gpio-104-dio-48e.o
(gcc version 7.2.0 x86_64)
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The ACCES I/O 104-DIO-48E series of devices contain two Programmable
Peripheral Interface (PPI) chips of type 82C55, which each feature three
8-bit ports of I/O. Since eight input lines are acquired on a single
port input read, the 104-DIO-48E GPIO driver may improve multiple input
reads by utilizing a get_multiple callback. This patch implements the
dio48e_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>
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>
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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/
...
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
The 104-dio-48e 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>
This patch sets the gpio_chip names option with an array of GPIO line
names that match the manual documentation for the ACCES 104-DIO-48E.
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>
Setting driver_data was necessary to access private data in the
dio48e_remove function. Now that the dio48e_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>
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 dio48e_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>
The ACCES 104-DIO-48E series 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>
There are only two control ports, each controlling three distinct I/O
ports. To compute the control port address offset for a respective I/O
port, the I/O port address offset should be divided by 3; dividing by 2
may result in not only the wrong address offset but possibly also an
out-of-bounds array memory access for a non-existent third control port.
Fixes: 1b06d64f73 ("gpio: Add GPIO support for the ACCES 104-DIO-48E")
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The ACCES 104-DIO-48E series communicates via the ISA bus. As such, it
is more appropriate to use the ISA bus driver over the platform driver
to control the ACCES 104-DIO-48E 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>
By the time request_region is called in the ACCES 104-DIO-48E 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>
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>
The ACCES 104-DIO-48E device provides 48 lines digital I/O via two
Programmable Peripheral Interface (PPI) chips of type 82C55. Bit C3 at
each 24-bit Group can be used as an external interrupt, triggered by a
rising edge.
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 dio_48e_base module parameter. The interrupt line number for the
device may be configured via the dio_48e_irq module parameter.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
William Breathitt Gray