The Freescale SPI chipselects are special: while everyone else
is using "cs-gpios" the Freescale platforms just use "gpios".
Fix this by responding with "gpios" when asking for "cs-gpios"
in a freescale device node, so we hide this pecularity from
the SPI core.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Since GPIO library operates with enumerator when it's subject to handle
the GPIO lookup flags, it will be better to clearly see what default means.

Thus, introduce GPIO_LOOKUP_FLAGS_DEFAULT entry to describe
the default assumptions.

While here, replace 0 by newly introduced constant.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The library uses enum gpio_lookup_flags to define the possible
characteristics of GPIO pin. Since enumerator listed only individual
bits the common use of it is in a form of a bitmask of
gpio_lookup_flags GPIO_* values. The more correct type for this is
unsigned long.

Due to above convert all users to use unsigned long instead of
enum gpio_lookup_flags except enumerator definition.

While here, make field and parameter descriptions consistent as well.
Suggested-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Simple string comparisons are cheaper than DT lookups, as the latter
involve taking a spinlock and traversing properties.
Hence optimize quirk checks by postponing DT lookups after string
comparisons.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: NMukesh Ojha <mojha@codeaurora.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

If the call to of_gpiochip_scan_gpios() in of_gpiochip_add() fails, no
error handling is performed.  This lead to the need of callers to call
of_gpiochip_remove() on failure, which causes "BAD of_node_put() on ..."
if the failure happened before the call to of_node_get().

Fix this by adding proper error handling.

Note that calling gpiochip_remove_pin_ranges() multiple times causes no
harm: subsequent calls are a no-op.

Fixes: dfbd379b ("gpio: of: Return error if gpio hog configuration failed")
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: NMukesh Ojha <mojha@codeaurora.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

"spi-cs-high" is going to be specified in child node of an SPI
controller's representing attached SPI device, so change the code to
look for it there, instead of checking parent node.
Signed-off-by: NAndrey Smirnov <andrew.smirnov@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: linux-gpio@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

SPI GPIO device has more than just "cs-gpio" property in its node and
would request those GPIOs as a part of its initialization. To avoid
applying CS-specific quirk to all of them add a check to make sure
that propname is "cs-gpios".
Signed-off-by: NAndrey Smirnov <andrew.smirnov@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: linux-gpio@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Handle both enable-gpio and enable-gpios properties of the GPIO
regulator in the quirk. The later is the preferred modern name
of the property.
Signed-off-by: NMarek Vasut <marek.vasut+renesas@gmail.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Jan Kotas <jank@cadence.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: linux-renesas-soc@vger.kernel.org
To: linux-gpio@vger.kernel.org
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Commit 0e7d6f94 ("gpio: of: Apply regulator-gpio quirk only to
enable-gpios") breaks the device tree ABI specified in the device tree
bindings for fixed regulators (compatible "regulator-fixed"). According
to these bindings the polarity of the GPIO is exclusively controlled by
the presence or absence of the enable-active-high property. As such the
polarity quirk implemented in of_gpio_flags_quirks() must be applied to
the GPIO specified for fixed regulators.

However, commit 0e7d6f94 ("gpio: of: Apply regulator-gpio quirk only
to enable-gpios") restricted the quirk to the enable-gpios property for
fixed regulators as well, whereas according to the commit message itself
it should only apply to "regulator-gpio" compatible device tree nodes.

Fix this by actually implementing what the offending commit intended,
which is to ensure that the quirk is applied to the GPIO specified by
the "enable-gpio" property for the "regulator-gpio" bindings only.

This fixes a regression on Jetson TX1 where the fixed regulator for the
HDMI +5V pin relies on the flags quirk for the proper polarity.

Fixes: 0e7d6f94 ("gpio: of: Apply regulator-gpio quirk only to enable-gpios")
Signed-off-by: NThierry Reding <treding@nvidia.com>
Tested-by: NMarek Vasut <marek.vasut@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Since commit d6cd33ad ("regulator: gpio: Convert to use descriptors")
the GPIO regulator had inverted the polarity of the control GPIO. This
problem manifested itself on systems with DT containing the following
description (snippet from salvator-common.dtsi):

	gpios = <&gpio5 1 GPIO_ACTIVE_HIGH>;
	gpios-states = <1>;
	states = <3300000 1
		  1800000 0>;

Prior to the aforementioned commit, the gpio-regulator code used
gpio_request_array() to claim the GPIO(s) specified in the "gpios"
DT node, while the commit changed that to devm_gpiod_get_index().

The legacy gpio_request_array() calls gpio_request_one() and then
gpiod_request(), which parses the DT flags of the "gpios" node and
populates the GPIO descriptor flags field accordingly.

The new devm_gpiod_get_index() calls gpiod_get_index(), then
of_find_gpio(), of_get_named_gpiod_flags() with flags != NULL,
and then of_gpio_flags_quirks(). Since commit a603a2b8
("gpio: of: Add special quirk to parse regulator flags"),
of_gpio_flags_quirks() contains a quirk for regulator-gpio
which was never triggered by the legacy gpio_request_array()
code path, but is triggered by devm_gpiod_get_index() code
path.

This quirk checks whether a GPIO is associated with a fixed
or gpio-regulator and if so, checks two additional conditions.
First, whether such GPIO is active-low, and if so, ignores the
active-low flag. Second, whether the regulator DT node does
have an "enable-active-high" property and if the property is
NOT present, sets the GPIO flags as active-low.

The second check triggers a problem, since it is applied to all
GPIOs associated with a gpio-regulator, rather than only on the
"enable" GPIOs, as the old code did. This changes the way the
gpio-regulator interprets the DT description of the control
GPIOs.

The old code using gpio_request_array() explicitly parsed the
"enable-active-high" DT property and only applied it to the
GPIOs described in the "enable-gpios" DT node, and only if
those were present.

This patch fixes the quirk code by only applying the quirk
to "enable-gpios", thus restoring the old behavior.
Signed-off-by: NMarek Vasut <marek.vasut+renesas@gmail.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Jan Kotas <jank@cadence.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: linux-renesas-soc@vger.kernel.org
To: linux-gpio@vger.kernel.org
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This commit adds support for configuring the pull-up and pull-down
resistors available in some GPIO controllers. While configuring
pull-up/pull-down is already possible through the pinctrl subsystem,
some GPIO controllers, especially simple ones such as GPIO expanders
on I2C, don't have any pinmuxing capability and therefore do not use
the pinctrl subsystem.

This commit implements the GPIO_PULL_UP and GPIO_PULL_DOWN flags,
which can be used from the Device Tree, to enable a pull-up or
pull-down resistor on a given GPIO.

The flag is simply propagated all the way to the core GPIO subsystem,
where it is used to call the gpio_chip ->set_config callback with the
appropriate existing PIN_CONFIG_BIAS_* values.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The SPI chip selects were not properly inspected due to
a logic inversion. This made SPI GPIOs not work.

Cc: Jan Kotas <jank@cadence.com>
Reported-by: NJan Kotas <jank@cadence.com>
Tested-by: NJan Kotas <jank@cadence.com>
Fixes: f3186dd8 ("spi: Optionally use GPIO descriptors for CS GPIOs")
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

The device tree bindings for the MMC card detect and
write protect lines specify that these should be active
low unless "cd-inverted" or "wp-inverted" has been
specified.

However that is not how the kernel code has worked. It
has always respected the flags passed to the phandle in
the device tree, but respected the "cd-inverted" and
"wp-inverted" flags such that if those are set, the
polarity will be the inverse of that specified in the
device tree.

Switch to behaving like the old code did and fix the
regression.

Fixes: 81c85ec1 ("gpio: OF: Parse MMC-specific CD and WP properties")
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Reported-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

When retrieveing CD (card detect) and WP (write protect)
GPIO handles from the device tree, make sure to assign
them active low by default unless the "cd-inverted" or
"wp-inverted" properties are set. These properties mean
that respective signal is active HIGH since the SDHCI
specification stipulates that this kind of signals
should be treated as active LOW.

If the twocell GPIO flag is also specified as active
low, well that's nice and we will silently ignore the
tautological specification.

If however the GPIO line is specified as active low
in the GPIO flasg cell and "cd-inverted" or "wp-inverted"
is also specified, the latter takes precedence and we
print a warning.

The current effect on the MMC slot-gpio core are as
follows:

For CD GPIOs: no effect. The current code in
mmc/core/host.c calls mmc_gpiod_request_cd() with
the "override_active_level" argument set to true,
which means that whatever the GPIO descriptor
thinks about active low/high will be ignored, the
core will use the MMC_CAP2_CD_ACTIVE_HIGH to keep
track of this and reads the raw value from the
GPIO descriptor, totally bypassing gpiolibs inversion
semantics. I plan to clean this up at a later point
passing the handling of inversion semantics over
to gpiolib, so this patch prepares the ground for
that.

Fow WP GPIOs: this is probably fixing a bug, because
the code in mmc/core/host.c calls mmc_gpiod_request_ro()
with the "override_active_level" argument set to false,
which means it will respect the inversion semantics of
the gpiolib and ignore the MMC_CAP2_RO_ACTIVE_HIGH
flag for everyone using this through device tree.
However the code in host.c confusingly goes to great
lengths setting up the MMC_CAP2_RO_ACTIVE_HIGH flag
from the GPIO descriptor and by reading the "wp-inverted"
property of the node. As far as I can tell this is all
in vain and the inversion is broken: device trees that
use "wp-inverted" do not work as intended, instead the
only way to actually get inversion on a line is by
setting the second cell flag to GPIO_ACTIVE_HIGH (which
will be the default) or GPIO_ACTIVE_LOW if they want
the proper MMC semantics. Presumably all device trees do
this right but we need to parse and handle this properly.

Cc: linux-mmc@vger.kernel.org
Cc: linux-gpio@vger.kernel.org
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

It's easy to verify that the change of drivers/gpio/gpiolib-of.c license
header to SPDX standard changes the license from GPLv2+ to GPLv2, and
this change corrects it.

Fixes: dae5f0af ("gpio: Use SPDX header for core library")
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Use the SPDX headers and cut down on boilerplate to indicate the
license in the core gpiolib implementation.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The SPI chipselects are assumed to be active low in the current
binding, so when we want to use GPIO descriptors and handle
the active low/high semantics in gpiolib, we need a special
parsing quirk to deal with this.

We check for the property "spi-cs-high" and if that is
NOT present we assume the CS line is active low.

If the line is tagged as active low in the device tree and
has no "spi-cs-high" property all is fine, the device
tree and the SPI bindings are in agreement.

If the line is tagged as active high in the device tree with
the second cell flag and has no "spi-cs-high" property we
enforce active low semantics (as this is the exception we can
just tag on the flag).

If the line is tagged as active low with the second cell flag
AND tagged with "spi-cs-high" the SPI active high property
takes precedence and we print a warning.

Cc: Mark Brown <broonie@kernel.org>
Cc: linux-spi@vger.kernel.org
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

gpiochip_add_data_with_key() adds the gpiochip to the gpio_devices list
before of_gpiochip_add() is called, but it's only the latter which sets
the ->of_xlate function pointer.  gpiochip_find() can be called by
someone else between these two actions, and it can find the chip and
call of_gpiochip_match_node_and_xlate() which leads to the following
crash due to a NULL ->of_xlate().

 Unhandled prefetch abort: page domain fault (0x01b) at 0x00000000
 Modules linked in: leds_gpio(+) gpio_generic(+)
 CPU: 0 PID: 830 Comm: insmod Not tainted 4.18.0+ #43
 Hardware name: ARM-Versatile Express
 PC is at   (null)
 LR is at of_gpiochip_match_node_and_xlate+0x2c/0x38
 Process insmod (pid: 830, stack limit = 0x(ptrval))
  (of_gpiochip_match_node_and_xlate) from  (gpiochip_find+0x48/0x84)
  (gpiochip_find) from  (of_get_named_gpiod_flags+0xa8/0x238)
  (of_get_named_gpiod_flags) from  (gpiod_get_from_of_node+0x2c/0xc8)
  (gpiod_get_from_of_node) from  (devm_fwnode_get_index_gpiod_from_child+0xb8/0x144)
  (devm_fwnode_get_index_gpiod_from_child) from  (gpio_led_probe+0x208/0x3c4 [leds_gpio])
  (gpio_led_probe [leds_gpio]) from  (platform_drv_probe+0x48/0x9c)
  (platform_drv_probe) from  (really_probe+0x1d0/0x3d4)
  (really_probe) from  (driver_probe_device+0x78/0x1c0)
  (driver_probe_device) from  (__driver_attach+0x120/0x13c)
  (__driver_attach) from  (bus_for_each_dev+0x68/0xb4)
  (bus_for_each_dev) from  (bus_add_driver+0x1a8/0x268)
  (bus_add_driver) from  (driver_register+0x78/0x10c)
  (driver_register) from  (do_one_initcall+0x54/0x1fc)
  (do_one_initcall) from  (do_init_module+0x64/0x1f4)
  (do_init_module) from  (load_module+0x2198/0x26ac)
  (load_module) from  (sys_finit_module+0xe0/0x110)
  (sys_finit_module) from  (ret_fast_syscall+0x0/0x54)

One way to fix this would be to rework the hairy registration sequence
in gpiochip_add_data_with_key(), but since I'd probably introduce a
couple of new bugs if I attempted that, simply add a check for a
non-NULL of_xlate function pointer in
of_gpiochip_match_node_and_xlate().  This works since the driver looking
for the gpio will simply fail to find the gpio and defer its probe and
be reprobed when the driver which is registering the gpiochip has fully
completed its probe.
Signed-off-by: NVincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

In preparation to remove the node name pointer from struct device_node,
convert printf users to use the %pOFn format specifier.

Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-gpio@vger.kernel.org
Signed-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Some platforms are not setting of_node in the driver. On these platforms
defining gpio-reserved-ranges on device tree leads to kernel crash.

It is due to some parts of the gpio core relying on the driver to set up
of_node,while other parts do themselves.This inconsistent behaviour leads
to a crash.

gpiochip_add_data_with_key() calls gpiochip_init_valid_mask() with of_node
as NULL. of_gpiochip_add() fills "of_node" and calls
of_gpiochip_init_valid_mask().

The fix is to move the assignment to chip->of_node from of_gpiochip_add()
to gpiochip_add_data_with_key().
Signed-off-by: NBiju Das <biju.das@bp.renesas.com>
Reviewed-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Tested-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This fixes up the handling of fixed regulator polarity
inversion flags: while I remembered to fix it for the
undocumented "reg-fixed-voltage" I forgot about the
official "regulator-fixed" binding, there are two ways
to do a fixed regulator.

The error was noticed and fixed.

Fixes: a603a2b8 ("gpio: of: Add special quirk to parse regulator flags")
Cc: Mark Brown <broonie@kernel.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Reported-by: NThierry Reding <thierry.reding@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The new helper returns index of the matching string in an array.
We are going to use it here.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Some qcom platforms make some GPIOs or pins unavailable for use by
non-secure operating systems, and thus reading or writing the registers
for those pins will cause access control issues. Add support for a DT
property to describe the set of GPIOs that are available for use so that
higher level OSes are able to know what pins to avoid reading/writing.
Non-DT platforms can add support by directly updating the
chip->valid_mask.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NStephen Boyd <swboyd@chromium.org>
Tested-by: NTimur Tabi <timur@codeaurora.org>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

of_get_named_gpiod_flags() used directly in of_find_gpio() or indirectly
through of_find_spi_gpio() or of_find_regulator_gpio() can return
-EPROBE_DEFER. This gets overwritten by the subsequent of_find_*_gpio()
calls.

This patch fixes this by trying of_find_spi_gpio() or
of_find_regulator_gpio() only if deferred probing was not requested by
the previous of_get_named_gpiod_flags() call.

Fixes: 6a537d48 ("gpio: of: Support regulator nonstandard GPIO properties")
Fixes: c8582339 ("gpio: of: Support SPI nonstandard GPIO properties")
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
[Augmented to fit with Maxime's patch]
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Commits c8582339 ("gpio: of: Support SPI nonstandard GPIO properties")
and 6a537d48 ("gpio: of: Support regulator nonstandard GPIO
properties") have introduced a regression in the way error codes from
of_get_named_gpiod_flags are handled.

Previously, those errors codes were returned immediately, but the two
commits mentioned above are now overwriting the error pointer, meaning that
whatever value has been returned will be dropped in favor of whatever the
two new functions will return.

This might not be a big deal except for EPROBE_DEFER, on which GPIOlib
customers will depend on, and that will now be returned as an hard error
which means that they will not probe anymore, instead of gently deferring
their probe.

Since EPROBE_DEFER basically means that we have found a valid property but
there was no GPIO controller registered to handle it, fix this issues by
returning it as soon as we encounter it.

Fixes: c8582339 ("gpio: of: Support SPI nonstandard GPIO properties")
Fixes: 6a537d48 ("gpio: of: Support regulator nonstandard GPIO properties")
Signed-off-by: NMaxime Ripard <maxime.ripard@bootlin.com>
[Fold in fix to the fix]
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Platforms like 96boards have a standardized connector/expansion
slot that exposes signals like GPIOs to expansion boards in an
SoC agnostic way. We'd like the DT overlays for the expansion
boards to be written once without knowledge of the SoC on the
other side of the connector. This avoids the unscalable
combinatorial explosion of a different DT overlay for each
expansion board and SoC pair.

Now that we have nexus support in the OF core let's change the
function call here that parses the phandle lists of gpios to use
the nexus variant. This allows us to remap phandles and their
arguments through any number of nexus nodes and end up with the
actual gpio provider being used.

Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: NStephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: NRob Herring <robh@kernel.org>

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.

Fixes: 6a537d48 ("gpio: of: Support regulator nonstandard GPIO properties")
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Reported-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

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.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

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: NLinus Walleij <linus.walleij@linaro.org>

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: NRob Herring <robh@kernel.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Following commit 9427ecbe ("gpio: Rework of_gpiochip_set_names()
to use device property accessors"), "gpio-line-names" DT property is
not retrieved anymore when chip->parent is not set by the driver.
This is due to OF based property reads having been replaced by device
based property reads.

This patch fixes that by making use of
fwnode_property_read_string_array() instead of
device_property_read_string_array() and handing over either
of_fwnode_handle(chip->of_node) or dev_fwnode(chip->parent)
to that function.

Fixes: 9427ecbe ("gpio: Rework of_gpiochip_set_names() to use device property accessors")
Cc: stable@vger.kernel.org
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

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: NAndrew Jeffery <andrew@aj.id.au>
Reviewed-by: NCharles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Literally.

I expect "lose" was meant here, rather than "loose", though you could feasibly
use a somewhat uncommon definition of "loose" to mean what would be meant by
"lose": "Loose the hounds" for instance, as in "Release the hounds".
Substituting in "value" for "hounds" gives "release the value", and makes some
sense, but futher substituting back to loose gives "loose the value" which
overall just seems a bit anachronistic.

Instead, use modern, pragmatic English and save a character.

Cc: Russell Currey <ruscur@russell.cc>
Signed-off-by: NAndrew Jeffery <andrew@aj.id.au>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Add descriptions for missing fields and fix up some parameter references
to match the code.
Signed-off-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.
Signed-off-by: NRob Herring <robh@kernel.org>
Cc: Tien Hock Loh <thloh@altera.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: "Sören Brinkmann" <soren.brinkmann@xilinx.com>
Cc: linux-gpio@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: NGregory Fong <gregory.0xf0@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Add new flags to allow users to specify that they are not concerned with
the status of GPIOs whilst in a sleep/low power state.
Signed-off-by: NCharles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Currently, the GPIO interface is said to Open Drain if it is Single
Ended and active LOW. Similarly, it is said as Open Source if it is
Single Ended and active HIGH.

The active HIGH/LOW is used in the interface for setting the pin
state to HIGH or LOW when enabling/disabling the interface.

In Open Drain interface, pin is set to HIGH by putting pin in
high impedance and LOW by driving to the LOW.

In Open Source interface, pin is set to HIGH by driving pin to
HIGH and set to LOW by putting pin in high impedance.

With above, the Open Drain/Source is unrelated to the active LOW/HIGH
in interface. There is interface where the enable/disable of interface
is ether active LOW or HIGH but it is Open Drain type.

Hence decouple the Open Drain with Single Ended + Active LOW and
Open Source with Single Ended + Active HIGH.

Adding different flag for the Open Drain/Open Source which is valid
only when Single ended flag is enabled.
Signed-off-by: NLaxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

When listing multiple GPIOs in the "gpios" property of a GPIO hog, only
the first GPIO is affected.  The user is left clueless about the
dysfunctioning of the other GPIOs specified.

Fix this by adding and documenting support for specifying multiple
GPIOs in a single GPIO hog.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Sylvain Lemieux reports the LPC32xx GPIO driver is broken since
commit 762c2e46 ("gpio: of: remove of_gpiochip_and_xlate() and
struct gg_data").  Probably, gpio-etraxfs.c and gpio-davinci.c are
broken too.

Those drivers register multiple gpio_chip that are associated to a
single OF node, and their own .of_xlate() checks if the passed
gpio_chip is valid.

Now, the problem is of_find_gpiochip_by_node() returns the first
gpio_chip found to match the given node.  So, .of_xlate() fails,
except for the first GPIO bank.

Reverting the commit could be a solution, but I do not want to go
back to the mess of struct gg_data.  Another solution here is to
take the match by a node pointer and the success of .of_xlate().
It is a bit clumsy to call .of_xlate twice; for gpio_chip matching
and for really getting the gpio_desc index.  Perhaps, our long-term
goal might be to convert the drivers to single chip registration,
but this commit will solve the problem until then.

Fixes: 762c2e46 ("gpio: of: remove of_gpiochip_and_xlate() and struct gg_data")
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reported-by: NSylvain Lemieux <slemieux.tyco@gmail.com>
Tested-by: NDavid Lechner <david@lechnology.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>