Linus Walleij [Thu, 18 Jan 2018 09:43:43 +0000 (10:43 +0100)]
gpio: Documentation update
Update a slew of documentation files with the latest changes in the
API/ABI. Again stress that sysfs is deprecated. Add all new flags and
clean up and move some text.
Colin Ian King [Tue, 16 Jan 2018 11:56:11 +0000 (11:56 +0000)]
gpiolib: remove redundant initialization of pointer desc
The initialized value stored in pointer desc is never read as it
is updated in the first executable statement in the function.
This is therefore redundant and can be removed.
Cleans up clang warning:
drivers/gpio/gpiolib.c:3710:20: warning: Value stored to 'desc'
during its initialization is never read
Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Linus Walleij [Tue, 16 Jan 2018 22:44:46 +0000 (23:44 +0100)]
gpio: of: Fix NPE from OF flags
Some calls to of_get_named_gpio() calls sets the flags
argument to NULL because they are not interested in the
flags. This caused a null pointer exception since we were
unconditionally using these flags. Fix it.
Markus Elfring [Fri, 12 Jan 2018 18:36:29 +0000 (19:36 +0100)]
gpio: stmpe: Improve a size determination in stmpe_gpio_probe()
Replace the specification of a data structure by a pointer dereference
as the parameter for the operator "sizeof" to make the corresponding size
determination a bit safer according to the Linux coding style convention.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Linus Walleij [Tue, 16 Jan 2018 07:29:50 +0000 (08:29 +0100)]
gpio: No NULL owner
Sometimes a GPIO is fetched with NULL as parent device, and
that is just fine. So under these circumstances, avoid using
dev_name() to provide a name for the GPIO line.
Linus Walleij [Sat, 13 Jan 2018 21:07:09 +0000 (22:07 +0100)]
gpio: 74x174: Include proper headers
This driver has no business including <linux/gpio.h> or
<linux/of_gpio.h>. Cut them and include <linux/gpio/driver.h>
and <linux/gpio/consumer.h> which is it they really needs.
Linus Walleij [Sat, 30 Dec 2017 15:26:36 +0000 (16:26 +0100)]
gpio: of: Add special quirk to parse regulator flags
While most GPIOs are indicated to be active low or open drain using
their twocell flags, we have legacy regulator bindings to take into
account.
Add a quirk respecting the special boolean active-high and open
drain flags when parsing regulator nodes for GPIOs.
This makes it possible to get rid of duplicated inversion semantics
handling in the regulator core and any regulator drivers parsing
and handling this separately.
Unfortunately the old regulator inversion semantics are specified
such that the presence or absence of "enable-active-high" solely
controls the semantics, so we cannot deprecate this in favor
of the phandle-provided inversion flag, instead any such phandle
inversion flag provided in the second cell of a GPIO handle must be
actively ignored, so we print a warning to contain the situation
and make things easy for the users.
Linus Walleij [Fri, 29 Dec 2017 21:52:02 +0000 (22:52 +0100)]
gpio: Export devm_gpiod_get_from_of_node() for consumers
We have been holding back on adding an API for fetching GPIO handles
directly from device nodes, strongly preferring to get it from the
spawn devices instead.
The fwnode interface however already contains an API for doing this,
as it is used for opaque device tree nodes or ACPI nodes for getting
handles to LEDs and keys that use GPIO: those are specified as one
child per LED/key in the device tree and are not individual devices.
However regulators present a special problem as they already have
helper functions to traverse the device tree from a regulator node
and two levels down to fill in data, and as it already traverses
GPIO nodes in its own way, and already holds a pointer to each
regulators device tree node, it makes most sense to export an
API to fetch the GPIO descriptor directly from the node.
We only support the devm_* version for now, hopefully no non-devres
version will be needed.
Linus Walleij [Fri, 29 Dec 2017 01:07:54 +0000 (02:07 +0100)]
gpio: Break out code to get a descriptor from a DT node
Sometimes a GPIO needs to be taken from a node without
a device associated with it. The fwnode accessor does this,
let's however break out the DT code for now.
Linus Walleij [Wed, 27 Dec 2017 15:37:44 +0000 (16:37 +0100)]
gpio: of: Support regulator nonstandard GPIO properties
Before it was clearly established that all GPIO properties in the
device tree shall be named "foo-gpios" (with the deprecated variant
"foo-gpio" for single lines) we unfortunately merged a few bindings
for regulators with random phandle names.
As we want to switch the GPIO regulator driver to using descriptors,
we need devm_gpiod_get() to return something reasonable when looking
up these in the device tree.
Put in a special #ifdef:ed kludge to do this special lookup only
for the regulator case and gets compiled out if we're not enabling
regulators. Supply a whitelist with properties we accept.
Cc: Rob Herring <robh@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Arnd Bergmann [Thu, 11 Jan 2018 08:35:15 +0000 (09:35 +0100)]
gpio: winbond: fix ISA_BUS_API dependency
The newly added GPIO driver for winbond chipsets causes a
circular dependency warning in Kconfig:
drivers/gpio/Kconfig:13:error: recursive dependency detected!
drivers/gpio/Kconfig:13: symbol GPIOLIB is selected by STX104
drivers/iio/adc/Kconfig:699: symbol STX104 depends on ISA_BUS_API
arch/Kconfig:830: symbol ISA_BUS_API is selected by GPIO_WINBOND
drivers/gpio/Kconfig:701: symbol GPIO_WINBOND depends on GPIOLIB
The underlying problem is that ISA_BUS_API is not meant to be selected by
device drivers, instead it is provided by the architectures that support
ISA add-on card devices, or in case of x86 have this explicitly enabled.
This particular driver appears to be different from the other ISA_BUS_API
based drivers, in that it is not normally an add-on card (ISA or PC104)
but instead is an LPC-attached component on the mainboard. We already
support other functionality provided by this chip, at least
drivers/watchdog/w83627hf_wdt.c and drivers/hwmon/w83627ehf.c, plus
there is a discovery function for this hardware in
drivers/parport/parport_pc.c.
If we want to use this driver without having to enable CONFIG_EXPERT,
it might be better to not use the isa_bus_type for it, but rather
turn it into a platform_driver, acpi_driver or add an MFD for it that
is shared with the wdt and hwmon portions and does the probing.
For now, this patch fixes the dependency by changing 'select' into
'depends on'.
Cc: William Breathitt Gray <vilhelm.gray@gmail.com> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Maciej S. Szmigiero <mail@maciej.szmigiero.name> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Fixes: a0d65009411c ("gpio: winbond: Add driver") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
gpio: Add GPIO support for the ACCES PCIe-IDIO-24 family
The ACCES PCIe-IDIO-24 device provides 56 lines of digital I/O (24 lines
of optically-isolated non-polarized digital inputs for AC and DC control
signals, 24 lines of isolated solid state FET digital outputs, and 8
non-isolated TTL/CMOS compatible programmable I/O). An interrupt is
generated when any of the inputs change state (low to high or high to
low).
Input filter control is not supported by this driver, and input filters
are deactivated by this driver. These devices are capable of
get_multiple and set_multiple functionality, but these functions have
not yet been implemented for this driver. Change-Of-State (COS)
detection functionality may be configured to fire interrupts on
exclusively rising/falling edges, but this driver currently only
implements COS detection for either both edges or none.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Stephen Boyd [Wed, 10 Jan 2018 01:58:46 +0000 (17:58 -0800)]
gpiolib: Export gpiochip_irqchip_irq_valid() to drivers
Some pinctrl drivers can use the gpiochip irq valid information
to figure out if certain gpios are exposed to the kernel for
usage or not. Expose this API so we can use it in the
pinmux_ops::request ops.
This commit adds GPIO driver for Winbond Super I/Os.
Currently, only W83627UHG model (also known as Nuvoton NCT6627UD)
is supported but in the future a support for other Winbond models,
too, can be added to the driver.
A module parameter "gpios" sets a bitmask of GPIO ports to enable
(bit 0 is GPIO1, bit 1 is GPIO2, etc.).
One should be careful which ports one tinkers with since some
might be managed by the firmware (for functions like powering on and
off, sleeping, BIOS recovery, etc.) and some of GPIO port pins are
physically shared with other devices included in the Super I/O chip.
Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Linus Walleij [Wed, 27 Dec 2017 15:37:44 +0000 (16:37 +0100)]
gpio: of: Support SPI nonstandard GPIO properties
Before it was clearly established that all GPIO properties in the
device tree shall be named "foo-gpios" (with the deprecated variant
"foo-gpio" for single lines) we unfortunately merged a few bindings
which named the lines "gpio-foo" instead.
This is most prominent in the GPIO SPI driver in Linux which names
the lines "gpio-sck", "gpio-mosi" and "gpio-miso".
As we want to switch the GPIO SPI driver to using descriptors, we
need devm_gpiod_get() to return something reasonable when looking
up these in the device tree.
Put in a special #ifdef:ed kludge to do this special lookup only
for the SPI case and gets compiled out if we're not enabling SPI.
If we have more oddly defined legacy GPIOs like this, they can be
handled in a similar manner.
Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Linus Walleij [Thu, 4 Jan 2018 21:31:11 +0000 (22:31 +0100)]
gpio: label descriptors using the device name
Some GPIO lines appear named "?" in the lsgpio dump due to their
requesting drivers not passing a reasonable label.
Most typically this happens if a device tree node just defines
gpios = <...> and not foo-gpios = <...>, the former gets named
"foo" and the latter gets named "?".
However the struct device passed in is always valid so let's
just label the GPIO with dev_name() on the device if no proper
label was passed.
Cc: Reported-by: Jason Kridner <jkridner@beagleboard.org> Reported-by: Jason Kridner <jkridner@beagleboard.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Linus Walleij [Fri, 29 Dec 2017 12:22:58 +0000 (13:22 +0100)]
gpio: omap: Give unique labels to each GPIO bank/chip
As we need to add GPIO lookup tables to the OMAP platforms, we
need to reference each GPIO chip with a unique label. Use the GPIO
base to name each chip, "gpio-0-31", "gpio-32-63" etc.
gpiolib: don't dereference a desc before validation
The fix restores a proper validation of an input gpio desc, which
might be needed to deal with optional GPIOs correctly.
Fixes: 02e479808b5d ("gpio: Alter semantics of *raw* operations to actually be raw") Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Rasmus Villemoes [Thu, 21 Dec 2017 00:27:04 +0000 (01:27 +0100)]
gpio: reduce descriptor validation code size
While we do need macros to be able to return from the "calling"
function, we can still factor the checks done by the VALIDATE_DESC*
macros into a real helper function. This reduces the backslashtitis,
avoids duplicating the logic in the two macros and saves about 1K of
generated code:
Timur Tabi [Wed, 20 Dec 2017 19:10:32 +0000 (13:10 -0600)]
pinctrl: qcom: disable GPIO groups with no pins
pinctrl-msm only accepts an array of GPIOs from 0 to n-1, and it expects
each group to support have only one pin (npins == 1).
We can support "sparse" GPIO maps if we allow for some groups to have zero
pins (npins == 0). These pins are "hidden" from the rest of the driver
and gpiolib.
Access to unavailable GPIOs is blocked via a request callback. If the
requested GPIO is unavailable, -EACCES is returned, which prevents
further access to that GPIO.
Signed-off-by: Timur Tabi <timur@codeaurora.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
We cannot blindly query the direction of all GPIOs when the pins are
first registered. The get_direction callback normally triggers a
read/write to hardware, but we shouldn't be touching the hardware for
an individual GPIO until after it's been properly claimed.
Signed-off-by: Timur Tabi <timur@codeaurora.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Christophe Leroy [Mon, 18 Dec 2017 10:08:31 +0000 (11:08 +0100)]
gpio: sysfs: correct error handling on 'value' attribute read.
'value' attribute is supposed to only return 0 or 1 according to
the documentation.
With today's implementation, if gpiod_get_value_cansleep() fails
the printed 'value' is a negative value.
This patch ensures that an error is returned on read instead.
Christophe Leroy [Mon, 18 Dec 2017 10:08:29 +0000 (11:08 +0100)]
gpio: sysfs: change 'value' attribute to prealloc
The GPIO 'value' attribute is time critical. A small bench with
'perf record' on the app below shows that 80% of the time spent in
sysfs_kf_seq_show() is spent in memset() for zeroising the buffer.
gpiolib: use kstrdup_const() for gpio_device label
Users often pass a pointer to a static string to gpiochip_add_data()
family of functions. Avoid unnecessary memory allocations with the
provided helper routine.
While at it: use a ternary operator instead of an if else for brevity.
The w1 master driver includes a complete open drain emulation
reimplementation among other things.
This converts the driver and all board files using it to use
GPIO descriptors associated with the device to look up the
GPIO wire, as well ass the optional pull-up GPIO line.
When probed from the device tree, the driver will just pick
descriptors and use them right off. For the two board files
in the kernel, we add descriptor lookups so we do not need
to keep any old platform data handling around for the GPIO
lines.
As the platform data is also a state container for this driver,
we augment it to contain the GPIO descriptors.
w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone
since this pair was a reimplementation of open drain emulation
which is now handled by gpiolib.
The special "linux,open-drain" flag is a bit of mishap here:
it has the same semantic as the same flags in I2C: it means
that something in the platform is setting up the line as
open drain behind our back. We handle this the same way as
in I2C.
To drive the pull-up, we need to bypass open drain emulation
in gpiolib for the line, and this is done by driving it high
using gpiod_set_raw_value() which has been augmented to have
the semantic of overriding the open drain emulation.
We also augment the documentation to reflect the way to pass
GPIO descriptors from the machine.
Quentin Schulz [Tue, 5 Dec 2017 14:46:45 +0000 (15:46 +0100)]
pinctrl: axp209: add programmable ADC muxing value
To prepare for patches that will add support for a new PMIC that has a
different GPIO adc muxing value, add an adc_mux within axp20x_pctl
structure and use it.
To prepare for patches that will add support for a new PMIC that has a
different GPIO input status register, add a gpio_status_offset within
axp20x_pctl structure and use it.
Quentin Schulz [Tue, 5 Dec 2017 14:46:43 +0000 (15:46 +0100)]
pinctrl: axp209: rename everything from gpio to pctl
This driver used to do only GPIO features of the GPIOs in X-Powers
AXP20X. Now that we have migrated everything to the pinctrl subsystem
and added pinctrl features, rename everything related to pinctrl from
gpio to pctl to ease the understanding of differences between GPIO
and pinctrl features.
The platform_get_irq() function returns negative if an error occurs.
zero or positive number on success. platform_get_irq() error checking
for zero is not correct.
Andrew Jeffery [Thu, 30 Nov 2017 03:55:24 +0000 (14:25 +1030)]
gpio: gpiolib: Generalise state persistence beyond sleep
General support for state persistence is added to gpiolib with the
introduction of a new pinconf parameter to propagate the request to
hardware. The existing persistence support for sleep is adapted to
include hardware support if the GPIO driver provides it. Persistence
continues to be enabled by default; in-kernel consumers can opt out, but
userspace (currently) does not have a choice.
The *_SLEEP_MAY_LOSE_VALUE and *_SLEEP_MAINTAIN_VALUE symbols are
renamed, dropping the SLEEP prefix to reflect that the concept is no
longer sleep-specific. I feel that renaming to just *_MAY_LOSE_VALUE
could initially be misinterpreted, so I've further changed the symbols
to *_TRANSITORY and *_PERSISTENT to address this.
The sysfs interface is modified only to keep consistency with the
chardev interface in enforcing persistence for userspace exports.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au> Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Colin Ian King [Tue, 28 Nov 2017 18:23:39 +0000 (18:23 +0000)]
gpio: gpio-stmpe: make various char arrays static const, shrinks object size
Don't populate the read-only arrays edge_det_values, rise_values and
fall_values on the stack but instead make them static and constify them.
Makes the object code smaller by over 240 bytes:
Before:
text data bss dec hex filename
9525 2520 192 12237 2fcd drivers/gpio/gpio-stmpe.o
After:
text data bss dec hex filename
9025 2776 192 11993 2ed9 drivers/gpio/gpio-stmpe.o
(gcc version 7.2.0 x86_64)
Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
gpio: mockup: modify the return value check for devm_irq_sim_init()
As discussed with Marc Zyngier: irq_sim_init() and its devres variant
should return the base of the allocated interrupt range on success
rather than 0. This will be modified later - first, change the way
users handle the return value of these routines.
The debugfs routines returning pointers can return NULL or error codes
embedded with ERR_PTR(). Check the return values with IS_ERR_OR_NULL().
While we're at it: make the error message more specific so it's not
confused with the one emitted when the top-level gpio-mockup debugfs
directory creation fails.
Keep GPIO chip callbacks, event trigger callbacks and mockup chip
setup code visibly separated. We're mostly good - just need to move
the line naming routine below.
Currently each chip has a dedicated directory in debugfs for event
triggers. We use the chip's label for the directory name, but the user
can't really associate these directories with chip names without
parsing the relevant sysfs entries.
Use chip names for directory names. For backward compatibility: create
links pointing to the actual directories named using the chip labels.
gpio: mockup: pass the named_lines parameter over platform_data
Move the last bits of code dealing with module parameters to the init
function. Add a new variable to platform data, which indicates to the
probe function if it should name the GPIO lines. If we ever want to
make the line naming more fine-grained (e.g. per chip switch) it will
be easier this way.
gpio: mockup: merge gpio_mockup_add() into gpio_mockup_probe()
Now that the probe() function only does what is should, there's no
need to split the chip adding logic into a separate routine. Merge
gpio_mockup_add() into gpio_mockup_probe().
We currently create a single platform device in init and then parse
the configuration passed to us via module parameters in probe() before
creating GPIO chips and registering them with the gpiolib framework.
The relation between platform devices and mockup chips should be 1:1.
Create a separate platform device for each mockup chip using convenient
helpers (platform_device_register_resndata()). Pass a platform data
structure to probe() in which the configuration (GPIO base, number of
lines, chip index) extracted from the module params is stored. Make
probe() create a single mockup chip for every platform device.
This approach has several advantages:
- we only parse the module parameters in init() and can bail out before
attaching any device if the input is invalid (currently we would
have to examine kernel logs),
- we'll get notified by the device framework about errors in probe()
for specific chips,
- probe() gets simplified and only does what it's supposed to.
gpio: mockup: parse the module params in init, not probe
If the module parameters are invalid, we should bail out from the init
function instead of detecting it during the device probe. That way we
don't even allow the user to load the module if we don't accept the
arguments.
gpio: omap: initialize gpioirq chip as part of gpiochip_add_data
Hence, series from Thierry Reding [1] merged - the OMAP GPIO driver can be
switched to reuse new feature and just fill new struct gpio_irq_chip before
calling gpiochip_add_data() instead of using few separate gpioirq chip
APIs. gpiochip_add_data() will do the job and create and initialize gpioirq
chip
Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
the hardware actually supports enabling both at the same time the
electrical result would be disastrous.
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