A patch from Ricardo got me thinking about some gpio chip
semantics so let's drop in some comments to make things
more clear around that.

Cc: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Cc: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

GPIOs with no programmable direction are not required to implement
direction_output nor direction_input.

If we try to set an output direction on an output-only GPIO or input
direction on an input-only GPIO simply return 0.

This allows this single direction GPIO to be used by libgpiod.
Signed-off-by: NRicardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

All the other core files are named "gpiolib-<something>" so
let's rename the devres as well so we have some logical
namespacing here.
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>

If a gpio instance has any GPIO bits requested we do a pm_runtime_get()
on the device. Now with cpu_pm handling the deeper SoC idle state quirks,
let's just remove pm_runtime_irq_safe() call and add a warning in case we
ever happen to encounter it.

Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Ladislav Michl <ladis@linux-mips.org>
Cc: Tero Kristo <t-kristo@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Acked-by: NGrygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

For a long time the gpio-omap custom PM calls have been annoying me so
let's replace them with cpu_pm instead. This will enable GPIO PM for
deeper idle states on omap4. And we can handle GPIO PM for omap2/3/4
in the same way.

Note that with this patch we are also slightly changing GPIO PM to be
less aggressive for omap3 and only will idle GPIO when PER context
may be lost.

For omap2, we don't need to save context and don't want to remove any
triggering so let's add a quirk flag for that.

Let's do this all in a single patch to avoid a situation where old
custom calls still are used with new code.

Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Ladislav Michl <ladis@linux-mips.org>
Cc: Tero Kristo <t-kristo@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Acked-by: NGrygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

I noticed that unlike omap2 and 3 based SoCs, omap4 based SoCs keep
the GPIO clocks enabled for GPIO level interrupts with wakeup enabled.
This blocks deeper idle states as the whole domain will stay busy.

The GPIO functional clock seems to stay enabled if the wakeup register
is enabled and a level interrupt is triggered. In that case the only
way to have the GPIO module idle is to reset it. It is possible this
has gone unnoticed with OSWR (Open SWitch Retention) and off mode
during idle resetting GPIO context most GPIO instances in the earlier
Android trees for example.

Looks like the way to deal with this is to have omap4 based SoCs
only set wake for the duration of idle for level interrupts, and clear
level registers for the idle. With level interrupts we can do this as
the level interrupt from device will be still there on resume.

I've taken the long path to fixing this to avoid yet more hard to
read code. I've set up a quirks flag, and a struct for function
pointers so we can use these to clean up other quirk handling easier
in the later patches. The current level quirk handling is moved to
the new functions.

Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Ladislav Michl <ladis@linux-mips.org>
Cc: Tero Kristo <t-kristo@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Acked-by: NGrygorii Strashko <grygorii.strashko@ti.com>
Tested-by: NKeerthy <j-keerthy@ti.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

New code introduced by commit bf9346f5 ("gpiolib: Identify arrays
matching GPIO hardware") forcibly tries to find an array member which
has its array index number equal to its hardware pin number and set
up an array info for possible fast bitmap processing of all arrray
pins belonging to that chip which also satisfy that numbering rule.

Depending on array content, it may happen that consecutive array
members which belong to the same chip but don't have array indexes
equal to their pin hardware numbers will be split into groups, some of
them processed together via the fast bitmap path, and rest of them
separetely.  However, applications may expect all those pins being
processed together with a single call to .set_multiple() chip callback,
like that was done before the change.

Limit applicability of fast bitmap processing path to cases where all
pins of consecutive array members starting from 0 which belong to the
same chip have their hardware numbers equal to their corresponding
array indexes.  That should still speed up processing of applications
using whole GPIO banks as I/O ports, while not breaking simultaneous
manipulation of consecutive pins of the same chip which don't follow
the equal numbering rule.

Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Tested-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

In new code introduced by commit b17566a6 ("gpiolib: Implement fast
processing path in get/set array"), bitmap index is not updated with
next found zero bit position as it should while skipping over pins
already processed via fast bitmap path, possibly resulting in an
infinite loop.  Fix it.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Tested-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Give the HTC EGPIO chips unique names, htc-egpio-0,
htc-egpio-1 etc, so that it gets possible to associate
machine descriptor tables with individual chips.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

These defines, structs and inline functions are used only internally by
the driver, they do not belong in platform_data. Move them.
Signed-off-by: NAndrew F. Davis <afd@ti.com>
Tested-by: NKeerthy <j-keerthy@ti.com>
Acked-by: NKeerthy <j-keerthy@ti.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Previously we created a controller structure per bank of GPIO pins. This
has since been changed to one per controller, but the allocation size
was not changed. Fix this here.

This also leaves the variable 'nbank' unused, instead of removing it,
move it down and use it to clean up a loop. For loops with multiple
initializers and/or iteration expressions, especially ones that don't
use those loop counters are quite hard to follow, fix this.
Signed-off-by: NAndrew F. Davis <afd@ti.com>
Tested-by: NKeerthy <j-keerthy@ti.com>
Acked-by: NKeerthy <j-keerthy@ti.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Use dev_name to get a unique label and use -1 for a base to get our
selection automatically. We pull in all GPIOs per chip now so this
does not have the effect of out of order labels like before.

We do these both together so we can drop all the static data in one
patch. This also lets us normalize the return paths as we don't need
any cleanup after this change.
Signed-off-by: NAndrew F. Davis <afd@ti.com>
Tested-by: NKeerthy <j-keerthy@ti.com>
Acked-by: NKeerthy <j-keerthy@ti.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

A bunch of core gpiolib files still include the <linux/gpio.h>
legacy API header for no good reason. After this only the
gpiolib-legacy.c file includes it, which is fine.

The sysfs ABI code has a pointless wrapper function around
gpio_to_desc() we can just loose.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Just use the SPDX license tag for these drivers.

Cc: patches@opensource.cirrus.com
Cc: Charles Keepax <ckeepax@opensource.cirrus.com>
Cc: Mark Brown <broonie@kernel.org>
Acked-by: NRichard Fitzgerald <rf@opensource.cirrus.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

These are GPIO drivers so just include <linux/gpio/driver.h>.

Cc: patches@opensource.cirrus.com
Cc: Charles Keepax <ckeepax@opensource.cirrus.com>
Cc: Mark Brown <broonie@kernel.org>
Acked-by: NRichard Fitzgerald <rf@opensource.cirrus.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Just use the SPDX license tag for this file.

Cc: Kamlakant Patel <kamlakant.patel@cavium.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This is a GPIO driver so include only <linux/gpio/driver.h>.

Cc: Kamlakant Patel <kamlakant.patel@cavium.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Just use the SPDX header for the license.

Cc: Daniel Drake <drake@endlessm.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This is a GPIO driver so include only <linux/gpio/driver.h>.

Cc: Daniel Drake <drake@endlessm.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Just use the SPDX header for the license.

Cc: Lars Poeschel <poeschel@lemonage.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This is a GPIO driver so include only <linux/gpio/driver.h>.

Cc: Lars Poeschel <poeschel@lemonage.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Just use the SPDX header for the license.
Acked-by: NBaruch Siach <baruch@tkos.co.il>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This is a GPIO driver so include only <linux/gpio/driver.h>.
Acked-by: NBaruch Siach <baruch@tkos.co.il>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This API is not used anywhere in the kernel and has remained
unused for years after being introduced.

Over time, we have developed a subsystem to deal with pin
control and this now managed pull up/down.

Delete the old and unused API. If this platform needs it,
we should implement a proper pin controller for it instead.

Cc: Yoichi Yuasa <yuasa@linux-mips.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Acked-by: NPaul Burton <paul.burton@mips.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This switches this file to use the SPDX license tag.

Cc: Yoichi Yuasa <yuasa@linux-mips.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This is a GPIO driver so include only <linux/gpio/driver.h>.

Cc: Yoichi Yuasa <yuasa@linux-mips.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Some drivers use a single irqchip for multiple gpiochips. As a result the
irqchip hooks are overridden for the first gpiochip that was added, but
for the other gpiochip instances this should not happen again, otherwise
we would go into an infinite recursion.

Check for this, but also log a message that the driver should be fixed
since this is bad practice.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Tested-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

EINVAL is very generic, use ENOTSUPP in case the gpiochip does not
provide this function. While removing the assignment from the 'status'
variable, use better indentation in the declaration block.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Certain GPIO descriptor arrays returned by gpio_get_array() may contain
information on direct mapping of array members to pins of a single GPIO
chip in hardware order.  In such cases, bitmaps of values can be passed
directly from/to the chip's .get/set_multiple() callbacks without
wasting time on iterations.

Add respective code to gpiod_get/set_array_bitmap_complex() functions.
Pins not applicable for fast path are processed as before, skipping
over the 'fast' ones.

Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

In order to make use of array info obtained from gpiod_get_array() and
speed up processing of arrays matching single GPIO chip layout, that
information must be passed to get/set array functions.  Extend the
functions' API with that additional parameter and update all users.
Pass NULL if a user builds an array itself from single GPIOs.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Peter Korsgaard <peter.korsgaard@barco.com>
Cc: Peter Rosin <peda@axentia.se>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Rojhalat Ibrahim <imr@rtschenk.de>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Michael Hennerich <Michael.Hennerich@analog.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Yegor Yefremov <yegorslists@googlemail.com>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Acked-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Certain GPIO array lookup results may map directly to GPIO pins of a
single GPIO chip in hardware order.  If that condition is recognized
and handled efficiently, significant performance gain of get/set array
functions may be possible.

While processing a request for an array of GPIO descriptors, identify
those which represent corresponding pins of a single GPIO chip.  Skip
over pins which require open source or open drain special processing.
Moreover, identify pins which require inversion.  Pass a pointer to
that information with the array to the caller so it can benefit from
enhanced performance as soon as get/set array functions can accept and
make efficient use of it.

Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Most users of get/set array functions iterate consecutive bits of data,
usually a single integer, while processing array of results obtained
from, or building an array of values to be passed to those functions.
Save time wasted on those iterations by changing the functions' API to
accept bitmaps.

All current users are updated as well.

More benefits from the change are expected as soon as planned support
for accepting/passing those bitmaps directly from/to respective GPIO
chip callbacks if applicable is implemented.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>
Cc: Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Peter Korsgaard <peter.korsgaard@barco.com>
Cc: Peter Rosin <peda@axentia.se>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Rojhalat Ibrahim <imr@rtschenk.de>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Michael Hennerich <Michael.Hennerich@analog.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Yegor Yefremov <yegorslists@googlemail.com>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Acked-by: NUlf Hansson <ulf.hansson@linaro.org>
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 concerns gpio edge detection for GPIO IRQs used from
userspace for GPIO event listeners.

Trying to work out the right event if it's not sure that the
examined gpio actually moved is impossible.

Consider two gpios "gpioA" and "gpioB" that share an interrupt.
gpioA's irq should trigger on any edge, gpioB's on a falling edge.
If now the common irq fires and both gpio lines are high, there
are several possibilities that could have happend:

 a) gpioA just had a low-to-high edge
 b) gpioB just had a high-to-low-to-high spike
 c) a combination of both a) and b)

While c) is unlikely (in most setups) a) and b) alone are bad
enough. Currently the code assumes case a) unconditionally and
doesn't report an event for gpioB. Note that even if there is no
irq sharing involved a spike for a gpio might not result in an
event if it's configured to trigger for a single edge only.

The only way to improve this is to drop support for interrupt
sharing. This way a spike results in an event for the right gpio
at least. Note that apart from dropping IRQF_SHARED this
effectively undoes commit df1e76f2
("gpiolib: skip unwanted events, don't convert them to opposite edge").

This obviously breaks setups that rely on interrupt sharing,
but given that this cannot be reliable, this is probably an
acceptable trade-off.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
[Assuming there are no users of interrupt sharing yet]
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Just use the SPDX identifier for the license.
Acked-by: NStefan Agner <stefan@agner.ch>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This is a GPIO driver so only include <linux/gpio/driver.h>.
Acked-by: NStefan Agner <stefan@agner.ch>
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>

Since this driver does not use the gpiolib irqchip helpers it will have to
allocate the irq resources and irq_en/disable itself.

Use the new gpiochip_req/relres_irq helpers to request/release all the
resources.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Cc: Ray Jui <rjui@broadcom.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

When using the gpiolib irqchip helpers install irq_enable/disable
hooks for the irqchip to ensure that gpiolib knows when the irq
is enabled or disabled, allowing drivers to disable the irq and then
use it as an output pin, and later switch the direction to input and
re-enable the irq.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

GPIO drivers call gpiochip_(un)lock_as_irq whenever they want to use a gpio
as an interrupt. This is done when the irq is requested and it marks the
gpio as in use by an interrupt.

This is problematic for cases where a gpio pin is used as an interrupt
pin, then, after the irq is disabled, is used as a regular gpio pin.
Currently it is not possible to do this other than by first freeing
the interrupt so gpiochip_unlock_as_irq is called, since an attempt to
switch the gpio direction for output will fail since gpiolib believes
that the gpio is in use for an interrupt and it does not know that it
the irq is actually disabled.

There are currently two drivers that would like to be able to do this:
the tda998x_drv.c driver where a regular gpio pin needs to be temporarily
reconfigured as an interrupt pin during CEC calibration, and the cec-gpio
driver where you want to configure the gpio pin as an interrupt while
waiting for traffic over the CEC bus, or as a regular pin when receiving or
transmitting a CEC message.

The solution is to add a new flag that is set when the irq is enabled,
and have gpiod_direction_output check for that flag.

We also add functions that drivers that do not use GPIOLIB_IRQCHIP
can call when they enable/disable the irq.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>