Core changes:
- A patch series from Hans Verkuil to make it possible to
enable/disable IRQs on a GPIO line at runtime and drive GPIO
lines as output without having to put/get them from scratch.
The irqchip callbacks have been improved so that they can
use only the fastpatch callbacks to enable/disable irqs
like any normal irqchip, especially the gpiod_lock_as_irq()
has been improved to be callable in fastpath context.
A bunch of rework had to be done to achieve this but it is
a big win since I never liked to restrict this to slowpath.
The only call requireing slowpath was try_module_get() and
this is kept at the .request_resources() slowpath callback.
In the GPIO CEC driver this is a big win sine a single
line is used for both outgoing and incoming traffic, and
this needs to use IRQs for incoming traffic while actively
driving the line for outgoing traffic.
- Janusz Krzysztofik improved the GPIO array API to pass a
"cookie" (struct gpio_array) and a bitmap for setting or
getting multiple GPIO lines at once. This improvement
orginated in a specific need to speed up an OMAP1 driver and
has led to a much better API and real performance gains
when the state of the array can be used to bypass a lot
of checks and code when we want things to go really fast.
The previous code would minimize the number of calls
down to the driver callbacks assuming the CPU speed was
orders of magnitude faster than the I/O latency, but this
assumption was wrong on several platforms: what we needed
to do was to profile and improve the speed on the hot
path of the array functions and this change is now
completed.
- Clean out the painful and hard to grasp BNF experiments
from the device tree bindings. Future approaches are looking
into using JSON schema for this purpose. (Rob Herring
is floating a patch series.)
New drivers:
- The RCAR driver now supports r8a774a1 (RZ/G2M).
- Synopsys GPIO via CREGs driver.
Major improvements:
- Modernization of the EP93xx driver to use irqdomain and
other contemporary concepts.
- The ingenic driver has been merged into the Ingenic pin
control driver and removed from the GPIO subsystem.
- Debounce support in the ftgpio010 driver.
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Merge tag 'gpio-v4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO updates from Linus Walleij:
"This is the bulk of GPIO changes for the v4.20 series:
Core changes:
- A patch series from Hans Verkuil to make it possible to
enable/disable IRQs on a GPIO line at runtime and drive GPIO lines
as output without having to put/get them from scratch.
The irqchip callbacks have been improved so that they can use only
the fastpatch callbacks to enable/disable irqs like any normal
irqchip, especially the gpiod_lock_as_irq() has been improved to be
callable in fastpath context.
A bunch of rework had to be done to achieve this but it is a big
win since I never liked to restrict this to slowpath. The only call
requireing slowpath was try_module_get() and this is kept at the
.request_resources() slowpath callback. In the GPIO CEC driver this
is a big win sine a single line is used for both outgoing and
incoming traffic, and this needs to use IRQs for incoming traffic
while actively driving the line for outgoing traffic.
- Janusz Krzysztofik improved the GPIO array API to pass a "cookie"
(struct gpio_array) and a bitmap for setting or getting multiple
GPIO lines at once.
This improvement orginated in a specific need to speed up an OMAP1
driver and has led to a much better API and real performance gains
when the state of the array can be used to bypass a lot of checks
and code when we want things to go really fast.
The previous code would minimize the number of calls down to the
driver callbacks assuming the CPU speed was orders of magnitude
faster than the I/O latency, but this assumption was wrong on
several platforms: what we needed to do was to profile and improve
the speed on the hot path of the array functions and this change is
now completed.
- Clean out the painful and hard to grasp BNF experiments from the
device tree bindings. Future approaches are looking into using JSON
schema for this purpose. (Rob Herring is floating a patch series.)
New drivers:
- The RCAR driver now supports r8a774a1 (RZ/G2M).
- Synopsys GPIO via CREGs driver.
Major improvements:
- Modernization of the EP93xx driver to use irqdomain and other
contemporary concepts.
- The ingenic driver has been merged into the Ingenic pin control
driver and removed from the GPIO subsystem.
- Debounce support in the ftgpio010 driver"
* tag 'gpio-v4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (116 commits)
gpio: Clarify kerneldoc on gpiochip_set_chained_irqchip()
gpio: Remove unused 'irqchip' argument to gpiochip_set_cascaded_irqchip()
gpio: Drop parent irq assignment during cascade setup
mmc: pwrseq_simple: Fix incorrect handling of GPIO bitmap
gpio: fix SNPS_CREG kconfig dependency warning
gpiolib: Initialize gdev field before is used
gpio: fix kernel-doc after devres.c file rename
gpio: fix doc string for devm_gpiochip_add_data() to not talk about irq_chip
gpio: syscon: Fix possible NULL ptr usage
gpiolib: Show correct direction from the beginning
pinctrl: msm: Use init_valid_mask exported function
gpiolib: Add init_valid_mask exported function
GPIO: add single-register GPIO via CREG driver
dt-bindings: Document the Synopsys GPIO via CREG bindings
gpio: mockup: use device properties instead of platform_data
gpio: Slightly more helpful debugfs
gpio: omap: Remove set but not used variable 'dev'
gpio: omap: drop omap_gpio_list
Accept partial 'gpio-line-names' property.
gpio: omap: get rid of the conditional PM runtime calls
...
This allows nonexclusive (simultaneous) access to a single
GPIO line for the fixed regulator enable line. This happens
when several regulators use the same GPIO for enabling and
disabling a regulator, and all need a handle on their GPIO
descriptor.
This solution with a special flag is not entirely elegant
and should ideally be replaced by something more careful as
this makes it possible for several consumers to
enable/disable the same GPIO line to the left and right
without any consistency. The current use inside the regulator
core should however be fine as it takes special care to
handle this.
For the state of the GPIO backend, this is still the
lesser evil compared to going back to global GPIO
numbers.
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Jon Hunter <jonathanh@nvidia.com>
Fixes: efdfeb079c ("regulator: fixed: Convert to use GPIO descriptor only")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
gpiochip_set_cascaded_irqchip() is passed 'parent_irq' as an argument
and then the address of that argument is assigned to the gpio chips
gpio_irq_chip 'parents' pointer shortly thereafter. This can't ever
work, because we've just assigned some stack address to a pointer that
we plan to dereference later in gpiochip_irq_map(). I ran into this
issue with the KASAN report below when gpiochip_irq_map() tried to setup
the parent irq with a total junk pointer for the 'parents' array.
BUG: KASAN: stack-out-of-bounds in gpiochip_irq_map+0x228/0x248
Read of size 4 at addr ffffffc0dde472e0 by task swapper/0/1
CPU: 7 PID: 1 Comm: swapper/0 Not tainted 4.14.72 #34
Call trace:
[<ffffff9008093638>] dump_backtrace+0x0/0x718
[<ffffff9008093da4>] show_stack+0x20/0x2c
[<ffffff90096b9224>] __dump_stack+0x20/0x28
[<ffffff90096b91c8>] dump_stack+0x80/0xbc
[<ffffff900845a350>] print_address_description+0x70/0x238
[<ffffff900845a8e4>] kasan_report+0x1cc/0x260
[<ffffff900845aa14>] __asan_report_load4_noabort+0x2c/0x38
[<ffffff900897e098>] gpiochip_irq_map+0x228/0x248
[<ffffff900820cc08>] irq_domain_associate+0x114/0x2ec
[<ffffff900820d13c>] irq_create_mapping+0x120/0x234
[<ffffff900820da78>] irq_create_fwspec_mapping+0x4c8/0x88c
[<ffffff900820e2d8>] irq_create_of_mapping+0x180/0x210
[<ffffff900917114c>] of_irq_get+0x138/0x198
[<ffffff9008dc70ac>] spi_drv_probe+0x94/0x178
[<ffffff9008ca5168>] driver_probe_device+0x51c/0x824
[<ffffff9008ca6538>] __device_attach_driver+0x148/0x20c
[<ffffff9008ca14cc>] bus_for_each_drv+0x120/0x188
[<ffffff9008ca570c>] __device_attach+0x19c/0x2dc
[<ffffff9008ca586c>] device_initial_probe+0x20/0x2c
[<ffffff9008ca18bc>] bus_probe_device+0x80/0x154
[<ffffff9008c9b9b4>] device_add+0x9b8/0xbdc
[<ffffff9008dc7640>] spi_add_device+0x1b8/0x380
[<ffffff9008dcbaf0>] spi_register_controller+0x111c/0x1378
[<ffffff9008dd6b10>] spi_geni_probe+0x4dc/0x6f8
[<ffffff9008cab058>] platform_drv_probe+0xdc/0x130
[<ffffff9008ca5168>] driver_probe_device+0x51c/0x824
[<ffffff9008ca59cc>] __driver_attach+0x100/0x194
[<ffffff9008ca0ea8>] bus_for_each_dev+0x104/0x16c
[<ffffff9008ca58c0>] driver_attach+0x48/0x54
[<ffffff9008ca1edc>] bus_add_driver+0x274/0x498
[<ffffff9008ca8448>] driver_register+0x1ac/0x230
[<ffffff9008caaf6c>] __platform_driver_register+0xcc/0xdc
[<ffffff9009c4b33c>] spi_geni_driver_init+0x1c/0x24
[<ffffff9008084cb8>] do_one_initcall+0x240/0x3dc
[<ffffff9009c017d0>] kernel_init_freeable+0x378/0x468
[<ffffff90096e8240>] kernel_init+0x14/0x110
[<ffffff9008086fcc>] ret_from_fork+0x10/0x18
The buggy address belongs to the page:
page:ffffffbf037791c0 count:0 mapcount:0 mapping: (null) index:0x0
flags: 0x4000000000000000()
raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: ffffffbf037791e0 ffffffbf037791e0 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffffffc0dde47180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffffffc0dde47200: f1 f1 f1 f1 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f2 f2
>ffffffc0dde47280: f2 f2 00 00 00 00 00 00 00 00 00 00 f3 f3 f3 f3
^
ffffffc0dde47300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffffffc0dde47380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Let's leave around one unsigned int in the gpio_irq_chip struct for the
single parent irq case and repoint the 'parents' array at it. This way
code is left mostly intact to setup parents and we waste an extra few
bytes per structure of which there should be only a handful in a system.
Cc: Evan Green <evgreen@chromium.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Fixes: e0d8972898 ("gpio: Implement tighter IRQ chip integration")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add a function that allows initializing the valid_mask from
gpiochip_add_data.
This prevents race conditions during gpiochip initialization.
If the function is not exported, then the old behaviour is respected,
this is, set all gpios as valid.
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Tested-by: Jeffrey Hugo <jhugo@codeaurora.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Internal helper function gpiod_set_array_value_complex() was changed to
return an error value, but not all gpiolib callers were updated to
propagate the new error up.
Fixes: 3027743f83 ("gpio: Remove VLA from gpiolib")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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: Linus 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: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus 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: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: Linus 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: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus 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: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Linus 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: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
GPIO drivers that do not use GPIOLIB_IRQCHIP can hook these into
the irq_request_resource and irq_release_resource callbacks of the
irq_chip so they correctly 'get' the module and lock the gpio line
for IRQ use.
This will simplify driver code.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Fix kernel-doc warning for missing struct member 'request_key':
../include/linux/gpio/driver.h:142: warning: Function parameter or member 'request_key' not described in 'gpio_irq_chip'
Fixes: 39c3fd5895 ("kernel/irq: Extend lockdep class for request mutex")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-gpio@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The bgpio_init() takes one of two arguments to specify a register
to set the direction of the GPIO line: either dirout that
indicates that a 1 in the bit in that register sets the
corresponding line to output, or dirin which indicates that
a 1 in the bit in that register sets the corresponding line to
input. Conversely setting the bit to 0 on these will turn the
line into input and output respectively. One of these can
be defined but not both.
This means that a platform that sets a bit to 1 for output
only defines dirout and a platform that sets a bit to 0 for
output only defines dirin. In short this defines the polarity
of the direction register.
Both can also be left as NULL meaning the GPIO chip is either
input only or output only.
Tomer Maimon discovered that for get/set chips (those where the
get and set registers are defined but no separate clear register,
and specifying BGPIOF_READ_OUTPUT_REG_SET so that we say we
want to read the output value from the SET register)
we are unconditionally reading the value from the SET register
when the direction bit is 1 and from the DAT register when the
direction bit is 0, not taking the direction bit polarity into
account.
It would be expected that when the direction bit is inverted
(dirin is defined but not dirout) we read the current value from
the DAT register when the bit is 1 and from the SET register
when the bit is 0.
Currently only some versions of ATH79, brcmstb, some versions of
CLP711x, GE, IOP and Loongson use the dirin mode (a 1 in the
register means input). They are unaffected because
BGPIOF_READ_OUTPUT_REG_SET is not set on any of them. (They
do not read back the SET register to figure out the output
value.) So this is no regression with current drivers.
However the behaviour is wrong and does not work with Tomer's
new driver where he needs to use the BGIOF_READ_OUTPUT_REG_SET.
This fixes the above issue by:
- Instead of defining separate functions for the inverted case,
set up a flag in the gpio_chip that indicates that the
direction is inverted.
- Remove the special inverted functions for setting
input/output and getting the direction, rely on the flag
instead.
- Respect this flag in bgpio_get_set() and
bgpio_get_set_multiple()
Reported-by: Tomer Maimon <tmaimon77@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
There should not be anything more than stated by the name of newly
introduced constants, i.e.
GPIOD_OUT_LOW_OPEN_DRAIN == GPIOD_OUT_LOW + open drain
and nothing more.
Make it better to read and slightly more robust by using GPIOD_OUT_LOW
and GPIOD_OUT_HIGH constants with open drain flag.
No functional change intended.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
On the Aspeed chip, the GPIOs can be under control of the ARM
chip or of the ColdFire coprocessor. (There's a third command
source, the LPC bus, which we don't use or support yet).
The control of which master is allowed to modify a given
GPIO is per-bank (8 GPIOs).
Unfortunately, systems already exist for which we want to
use GPIOs of both sources in the same bank.
This provides an API exported by the gpio-aspeed driver
that an aspeed coprocessor driver can use to "grab" some
GPIOs for use by the coprocessor, and allow the coprocessor
driver to provide callbacks for arbitrating access.
Once at least one GPIO of a given bank has been "grabbed"
by the coprocessor, the entire bank is marked as being
under coprocessor control. It's command source is switched
to the coprocessor.
If the ARM then tries to write to a GPIO in such a marked bank,
the provided callbacks are used to request access from the
coprocessor driver, which is responsible to doing whatever
is necessary to "pause" the coprocessor or prevent it from
trying to use the GPIOs while the ARM is doing its accesses.
During that time, the command source for the bank is temporarily
switched back to the ARM.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The GPIO (descriptor) API registers a "label" naming what is
currently using the GPIO line. Typically this is taken from
things like the device tree node, so "reset-gpios" will result
in he line being labeled "reset".
The technical effect is pretty much zero: the use is for
debug and introspection, such as "lsgpio" and debugfs files.
However sometimes the user want this cuddly feeling of
listing all GPIO lines and seeing exactly what they are for
and it gives a very fulfilling sense of control. Especially
in the cases when the device tree node doesn't provide a
good name, or anonymous GPIO lines assigned just to
"gpios" in the device tree because the usage is implicit.
For these cases it may be nice to be able to label the
line directly and explicitly.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The new challenge is to remove VLAs from the kernel
(see https://lkml.org/lkml/2018/3/7/621) to eventually
turn on -Wvla.
Using a kmalloc array is the easy way to fix this but kmalloc is still
more expensive than stack allocation. Introduce a fast path with a
fixed size stack array to cover most chip with gpios below some fixed
amount. The slow path dynamically allocates an array to cover those
chips with a large number of gpios.
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Phil Reid <preid@electromag.com.au>
Reviewed-and-tested-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Laura Abbott <labbott@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Board files constitute a significant part of the users of the legacy
GPIO framework. In many cases they only export a line and set its
desired value. We could use GPIO hogs for that like we do for DT and
ACPI but there's no support for that in machine code.
This patch proposes to extend the machine.h API with support for
registering hog tables in board files.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus 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: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Tested-by: Timur Tabi <timur@codeaurora.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Core changes:
- Disallow open drain and open source flags to be set
simultaneously. This doesn't make electrical sense, and would
the hardware actually respond to this setting, the result
would be short circuit.
- ACPI GPIO has a new core infrastructure for handling quirks.
The quirks are there to deal with broken ACPI tables centrally
instead of pushing the work to individual drivers. In the world
of BIOS writers, the ACPI tables are perfect. Until they find a
mistake in it. When such a mistake is found, we can patch it
with a quirk. It should never happen, the problem is that it
happens. So we accomodate for it.
- Several documentation updates.
- Revert the patch setting up initial direction state from
reading the device. This was causing bad things for drivers
that can't read status on all its pins. It is only affecting
debugfs information quality.
- Label descriptors with the device name if no explicit label is
passed in.
- Pave the ground for transitioning SPI and regulators to use
GPIO descriptors by implementing some quirks in the device tree
GPIO parsing code.
New drivers:
- New driver for the Access PCIe IDIO 24 family.
Other:
- Major refactorings and improvements to the GPIO mockup driver
used for test and verification.
- Moved the AXP209 driver over to pin control since it gained a
pin control back-end. These patches will appear (with the same
hashes) in the pin control pull request as well.
- Convert the onewire GPIO driver w1-gpio to use descriptors.
This is merged here since the W1 maintainers send very few
pull requests and he ACKed it.
- Start to clean up driver headers using <linux/gpio.h> to just
use <linux/gpio/driver.h> as appropriate.
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Merge tag 'gpio-v4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO updates from Linus Walleij:
"The is the bulk of GPIO changes for the v4.16 kernel cycle. It is
pretty calm this time around I think. I even got time to get to things
like starting to clean up header includes.
Core changes:
- Disallow open drain and open source flags to be set simultaneously.
This doesn't make electrical sense, and would the hardware actually
respond to this setting, the result would be short circuit.
- ACPI GPIO has a new core infrastructure for handling quirks. The
quirks are there to deal with broken ACPI tables centrally instead
of pushing the work to individual drivers. In the world of BIOS
writers, the ACPI tables are perfect. Until they find a mistake in
it. When such a mistake is found, we can patch it with a quirk. It
should never happen, the problem is that it happens. So we
accomodate for it.
- Several documentation updates.
- Revert the patch setting up initial direction state from reading
the device. This was causing bad things for drivers that can't read
status on all its pins. It is only affecting debugfs information
quality.
- Label descriptors with the device name if no explicit label is
passed in.
- Pave the ground for transitioning SPI and regulators to use GPIO
descriptors by implementing some quirks in the device tree GPIO
parsing code.
New drivers:
- New driver for the Access PCIe IDIO 24 family.
Other:
- Major refactorings and improvements to the GPIO mockup driver used
for test and verification.
- Moved the AXP209 driver over to pin control since it gained a pin
control back-end. These patches will appear (with the same hashes)
in the pin control pull request as well.
- Convert the onewire GPIO driver w1-gpio to use descriptors. This is
merged here since the W1 maintainers send very few pull requests
and he ACKed it.
- Start to clean up driver headers using <linux/gpio.h> to just use
<linux/gpio/driver.h> as appropriate"
* tag 'gpio-v4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (103 commits)
gpio: Timestamp events in hardirq handler
gpio: Fix kernel stack leak to userspace
gpio: Fix a documentation spelling mistake
gpio: Documentation update
gpiolib: remove redundant initialization of pointer desc
gpio: of: Fix NPE from OF flags
gpio: stmpe: Delete an unnecessary variable initialisation in stmpe_gpio_probe()
gpio: stmpe: Move an assignment in stmpe_gpio_probe()
gpio: stmpe: Improve a size determination in stmpe_gpio_probe()
gpio: stmpe: Use seq_putc() in stmpe_dbg_show()
gpio: No NULL owner
gpio: stmpe: i2c transfer are forbiden in atomic context
gpio: davinci: Include proper header
gpio: da905x: Include proper header
gpio: cs5535: Include proper header
gpio: crystalcove: Include proper header
gpio: bt8xx: Include proper header
gpio: bcm-kona: Include proper header
gpio: arizona: Include proper header
gpio: amd8111: Include proper header
...
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.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Linus 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: 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>
Pull i2c updates from Wolfram Sang:
"This contains two bigger than usual tree-wide changes this time. They
all have proper acks, caused no merge conflicts in linux-next where
they have been for a while. They are namely:
- to-gpiod conversion of the i2c-gpio driver and its users (touching
arch/* and drivers/mfd/*)
- adding a sbs-manager based on I2C core updates to SMBus alerts
(touching drivers/power/*)
Other notable changes:
- i2c_boardinfo can now carry a dev_name to be used when the device
is created. This is because some devices in ACPI world need fixed
names to find the regulators.
- the designware driver got a long discussed overhaul of its PM
handling. img-scb and davinci got PM support, too.
- at24 driver has way better OF support. And it has a new maintainer.
Thanks Bartosz for stepping up!
The rest is regular driver updates and fixes"
* 'i2c/for-4.15' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (55 commits)
ARM: sa1100: simpad: Correct I2C GPIO offsets
i2c: aspeed: Deassert reset in probe
eeprom: at24: Add OF device ID table
MAINTAINERS: new maintainer for AT24 driver
i2c: nuc900: remove platform_data, too
i2c: thunderx: Remove duplicate NULL check
i2c: taos-evm: Remove duplicate NULL check
i2c: Make i2c_unregister_device() NULL-aware
i2c: xgene-slimpro: Support v2
i2c: mpc: remove useless variable initialization
i2c: omap: Trigger bus recovery in lockup case
i2c: gpio: Add support for named gpios in DT
dt-bindings: i2c: i2c-gpio: Add support for named gpios
i2c: gpio: Local vars in probe
i2c: gpio: Augment all boardfiles to use open drain
i2c: gpio: Enforce open drain through gpiolib
gpio: Make it possible for consumers to enforce open drain
i2c: gpio: Convert to use descriptors
power: supply: sbs-message: fix some code style issues
power: supply: sbs-battery: remove unchecked return var
...
CORE:
- Fix the semantics of raw GPIO to actually be raw. No
inversion semantics as before, but also no open draining,
and allow the raw operations to affect lines used for
interrupts as the caller supposedly knows what they are
doing if they are getting the big hammer.
- Rewrote the __inner_function() notation calls to names that
make more sense. I just find this kind of code disturbing.
- Drop the .irq_base() field from the gpiochip since now all
IRQs are mapped dynamically. This is nice.
- Support for .get_multiple() in the core driver API. This
allows us to read several GPIO lines with a single
register read. This has high value for some usecases: it
can be used to create oscilloscopes and signal analyzers
and other things that rely on reading several lines at
exactly the same instant. Also a generally nice
optimization. This uses the new assign_bit() macro from
the bitops lib that was ACKed by Andrew Morton and
is implemented for two drivers, one of them being the
generic MMIO driver so everyone using that will be able
to benefit from this.
- Do not allow requests of Open Drain and Open Source
setting of a GPIO line simultaneously. If the hardware
actually supports enabling both at the same time the
electrical result would be disastrous.
- A new interrupt chip core helper. This will be helpful
to deal with "banked" GPIOs, which means GPIO controllers
with several logical blocks of GPIO inside them. This
is several gpiochips per device in the device model, in
contrast to the case when there is a 1-to-1 relationship
between a device and a gpiochip.
NEW DRIVERS:
- Maxim MAX3191x industrial serializer, a very interesting
piece of professional I/O hardware.
- Uniphier GPIO driver. This is the GPIO block from the
recent Socionext (ex Fujitsu and Panasonic) platform.
- Tegra 186 driver. This is based on the new banked GPIO
infrastructure.
OTHER IMPROVEMENTS:
- Some documentation improvements.
- Wakeup support for the DesignWare DWAPB GPIO controller.
- Reset line support on the DesignWare DWAPB GPIO controller.
- Several non-critical bug fixes and improvements for the
Broadcom BRCMSTB driver.
- Misc non-critical bug fixes like exotic errorpaths, removal
of dead code etc.
- Explicit comments on fall-through switch() statements.
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Merge tag 'gpio-v4.15-1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO updates from Linus Walleij:
"This is the bulk of GPIO changes for the v4.15 kernel cycle:
Core:
- Fix the semantics of raw GPIO to actually be raw. No inversion
semantics as before, but also no open draining, and allow the raw
operations to affect lines used for interrupts as the caller
supposedly knows what they are doing if they are getting the big
hammer.
- Rewrote the __inner_function() notation calls to names that make
more sense. I just find this kind of code disturbing.
- Drop the .irq_base() field from the gpiochip since now all IRQs are
mapped dynamically. This is nice.
- Support for .get_multiple() in the core driver API. This allows us
to read several GPIO lines with a single register read. This has
high value for some usecases: it can be used to create
oscilloscopes and signal analyzers and other things that rely on
reading several lines at exactly the same instant. Also a generally
nice optimization. This uses the new assign_bit() macro from the
bitops lib that was ACKed by Andrew Morton and is implemented for
two drivers, one of them being the generic MMIO driver so everyone
using that will be able to benefit from this.
- Do not allow requests of Open Drain and Open Source setting of a
GPIO line simultaneously. If the hardware actually supports
enabling both at the same time the electrical result would be
disastrous.
- A new interrupt chip core helper. This will be helpful to deal with
"banked" GPIOs, which means GPIO controllers with several logical
blocks of GPIO inside them. This is several gpiochips per device in
the device model, in contrast to the case when there is a 1-to-1
relationship between a device and a gpiochip.
New drivers:
- Maxim MAX3191x industrial serializer, a very interesting piece of
professional I/O hardware.
- Uniphier GPIO driver. This is the GPIO block from the recent
Socionext (ex Fujitsu and Panasonic) platform.
- Tegra 186 driver. This is based on the new banked GPIO
infrastructure.
Other improvements:
- Some documentation improvements.
- Wakeup support for the DesignWare DWAPB GPIO controller.
- Reset line support on the DesignWare DWAPB GPIO controller.
- Several non-critical bug fixes and improvements for the Broadcom
BRCMSTB driver.
- Misc non-critical bug fixes like exotic errorpaths, removal of dead
code etc.
- Explicit comments on fall-through switch() statements"
* tag 'gpio-v4.15-1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (65 commits)
gpio: tegra186: Remove tegra186_gpio_lock_class
gpio: rcar: Add r8a77995 (R-Car D3) support
pinctrl: bcm2835: Fix some merge fallout
gpio: Fix undefined lock_dep_class
gpio: Automatically add lockdep keys
gpio: Introduce struct gpio_irq_chip.first
gpio: Disambiguate struct gpio_irq_chip.nested
gpio: Add Tegra186 support
gpio: Export gpiochip_irq_{map,unmap}()
gpio: Implement tighter IRQ chip integration
gpio: Move lock_key into struct gpio_irq_chip
gpio: Move irq_valid_mask into struct gpio_irq_chip
gpio: Move irq_nested into struct gpio_irq_chip
gpio: Move irq_chained_parent to struct gpio_irq_chip
gpio: Move irq_default_type to struct gpio_irq_chip
gpio: Move irq_handler to struct gpio_irq_chip
gpio: Move irqdomain into struct gpio_irq_chip
gpio: Move irqchip into struct gpio_irq_chip
gpio: Introduce struct gpio_irq_chip
pinctrl: armada-37xx: remove unused variable
...
In order to avoid lockdep boilerplate in individual drivers, turn the
gpiochip_add_data() function into a macro that creates a unique class
key for each driver.
Note that this has the slight disadvantage of adding a key for each
driver registered with the system. However, these keys are 8 bytes in
size, which is negligible and a small price to pay for generic
infrastructure.
Suggested-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Grygorii Strashko <grygorii.strashko@ti.com>
[renane __gpiochip_add_data() to gpiochip_add_data_with_key]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Some GPIO chips cannot support sparse IRQ numbering and therefore need
to manually allocate their interrupt descriptors statically. For these
cases, a driver can pass the first allocated IRQ via the struct
gpio_irq_chip's "first" field and thereby cause the IRQ domain to map
all IRQs during initialization.
Suggested-by: Grygorii Strashko <grygorii.strashko@ti.com>
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>
The nested field in struct gpio_irq_chip currently has two meanings. On
one hand it marks an IRQ chip as being nested (as opposed to chained),
while on the other hand it also means that an IRQ chip uses nested
thread handlers.
However, nested IRQ chips can already be identified by the fact that
they don't pass a parent handler (the driver would instead already have
installed a nested handler using request_irq()).
Therefore, the only use for the nested attribute is to inform gpiolib
that an IRQ chip uses nested thread handlers (as opposed to regular,
non-threaded handlers). To clarify its purpose, rename the field to
"threaded".
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>
Export these functions so that drivers can explicitly use these when
setting up their IRQ domain.
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>
Currently GPIO drivers are required to add the GPIO chip and its
corresponding IRQ chip separately, which can result in a lot of
boilerplate. Use the newly introduced struct gpio_irq_chip, embedded in
struct gpio_chip, that drivers can fill in if they want the GPIO core
to automatically register the IRQ chip associated with a GPIO 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>
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>
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>
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>
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>
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>
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>
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>
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>
This new structure will be used to group all fields related to interrupt
handling in a GPIO chip. Doing so will properly namespace these fields
and make it easier to distinguish which fields are used for IRQ support.
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>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some busses, like I2C, strictly need to have the line handled
as open drain, i.e. not actively driven high. For this reason
the i2c-gpio.c bit-banged I2C driver is reimplementing open
drain handling outside of gpiolib.
This is not very optimal. Instead make it possible for a
consumer to explcitly express that the line must be handled
as open drain instead of allowing local hacks papering over
this issue.
The descriptor tables, whether DT, ACPI or board files, should
of course have flagged these lines as open drain. E.g.:
enum gpio_lookup_flags GPIO_OPEN_DRAIN for a board file, or
gpios = <&foo 42 GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN>; in a
device tree using <dt-bindings/gpio/gpio.h>
But more often than not, these descriptors are wrong. So
we need to make it possible for consumers to enforce this
open drain behaviour.
We now have two new enumerated GPIO descriptor config flags:
GPIOD_OUT_LOW_OPEN_DRAIN and GPIOD_OUT_HIGH_OPEN_DRAIN
that will set up the lined enforced as open drain as output
low or high, using open drain (if the driver supports it)
or using open drain emulation (setting the line as input
to drive it high) from the gpiolib core.
Cc: linux-gpio@vger.kernel.org
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The vtable call pin2mask() was introducing a vtable function call
in every gpiochip callback for a generic MMIO GPIO chip. This was
not exactly efficient. (Maybe link-time optimization could get rid of
it, I don't know.)
After removing all external calls into this API we can make it a
boolean flag in the struct gpio_chip call and sink the function into
the gpio-mmio driver yielding encapsulation and potential speedups.
Cc: Anton Vorontsov <anton@enomsg.org>
Signed-off-by: Linus 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: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
SPI-attached GPIO controllers typically read out all inputs in one go.
If callers desire the values of multipe inputs, ideally a single readout
should take place to return the desired values. However the current
driver API only offers a ->get callback but no ->get_multiple (unlike
->set_multiple, which is present). Thus, to read multiple inputs, a
full readout needs to be performed for every single value (barring
driver-internal caching), which is inefficient.
In fact, the lack of a ->get_multiple callback has been bemoaned
repeatedly by the gpio subsystem maintainer:
http://www.spinics.net/lists/linux-gpio/msg10571.htmlhttp://www.spinics.net/lists/devicetree/msg121734.html
Introduce the missing callback. Add corresponding consumer functions
such as gpiod_get_array_value(). Amend linehandle_ioctl() to take
advantage of the newly added infrastructure. Update the documentation.
Cc: Rojhalat Ibrahim <imr@rtschenk.de>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Linus Torvalds