This converts the COH901 pin control driver to register its
chained irq handler and irqchip using the helpers in the
gpiolib core.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This converts the Nomadik pin control driver to register its
chained irq handler and irqchip using the helpers in the
gpiolib core.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This converts the PL061 driver to register its chained irq
handler and irqchip using the helpers in the gpiolib core.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This provides a function gpiochip_irqchip_add() to set
up an irqchip for a GPIO controller, and a function
gpiochip_set_chained_irqchip() to chain it to a parent
irqchip.
Most GPIOs are of the type where a number of lines form
a cascaded interrupt controller chained onto
the primary system interrupt controller (or further down the
chain) so let's add this helper and factor the code to
request the lines to be used as IRQs, the .to_irq() function
and the irqdomain into the core as well.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The old platform data struct is just a leftover from the times
when the driver was not probed exclusively from the device tree.
Factor this into the general state container and simplify the
probe path.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The "secondary irq" in the nomadik pin control driver is actually
not secondary (as in: can occur any time alongside the ordinary
irq), it is a latent IRQ. It is an IRQ that has occurred when
the system was in sleep state and has been cached in a special
register flagged from the low power management unit (PRCM).
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
SYSCON driver was designed for using memory areas (registers)
that are used in several subsystems. There are systems (CPUs)
which use bits in one register for various purposes and thus
should be handled by various kernel subsystems. This driver
allows you to use the individual SYSCON bits as GPIOs.
ARM CLPS711X SYSFLG1 input lines has been added as first user
of this driver.
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This switches the COH901 GPIO driver over to using the
.request_resources() and .release_resources() callbacks from
the irqchip vtable and separate the calls from the .enable()
and .disable() callbacks as the latter cannot really say no
to a request, whereas the resource callbacks can.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This switches all GPIO and pin control drivers with irqchips
that were using .startup() and .shutdown() callbacks to lock
GPIO lines for IRQ usage over to using the .request_resources()
and .release_resources() callbacks just introduced into the
irqchip vtable.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
GPIO operation regions is a new feature introduced in ACPI 5.0
specification. This feature adds a way for platform ASL code to call back
to OS GPIO driver and toggle GPIO pins.
An example ASL code from Lenovo Miix 2 tablet with only relevant part
listed:
Device (\_SB.GPO0)
{
Name (AVBL, Zero)
Method (_REG, 2, NotSerialized)
{
If (LEqual (Arg0, 0x08))
{
// Marks the region available
Store (Arg1, AVBL)
}
}
OperationRegion (GPOP, GeneralPurposeIo, Zero, 0x0C)
Field (GPOP, ByteAcc, NoLock, Preserve)
{
Connection (
GpioIo (Exclusive, PullDefault, 0, 0, IoRestrictionOutputOnly,
"\\_SB.GPO0", 0x00, ResourceConsumer,,)
{
0x003B
}
),
SHD3, 1,
}
}
Device (SHUB)
{
Method (_PS0, 0, Serialized)
{
If (LEqual (\_SB.GPO0.AVBL, One))
{
Store (One, \_SB.GPO0.SHD3)
Sleep (0x32)
}
}
Method (_PS3, 0, Serialized)
{
If (LEqual (\_SB.GPO0.AVBL, One))
{
Store (Zero, \_SB.GPO0.SHD3)
}
}
}
How this works is that whenever _PS0 or _PS3 method is run (typically when
SHUB device is transitioned to D0 or D3 respectively), ASL code checks if
the GPIO operation region is available (\_SB.GPO0.AVBL). If it is we go and
store either 0 or 1 to \_SB.GPO0.SHD3.
Now, when ACPICA notices ACPI GPIO operation region access (the store
above) it will call acpi_gpio_adr_space_handler() that then toggles the
GPIO accordingly using standard gpiolib interfaces.
Implement the support by registering GPIO operation region handlers for all
GPIO devices that have an ACPI handle. First time the GPIO is used by the
ASL code we make sure that the GPIO stays requested until the GPIO chip
driver itself is unloaded. If we find out that the GPIO is already
requested we just toggle it according to the value got from ASL code.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Nothing prevents GPIO drivers from returning values outside the
boolean range, and as it turns out a few drivers are actually doing so.
These values were passed as-is to unsuspecting consumers and created
confusion.
This patch makes the internal _gpiod_get_raw_value() function return a
bool, effectively clamping the GPIO value to the boolean range no
matter what the driver does.
While we are at it, we also change the value parameter of
_gpiod_set_raw_value() to bool type before drivers start doing funny
things with it as well.
Another way to fix this would be to change the prototypes of the driver
interface to use bool directly, but this would require a huge
cross-systems patch so this simpler solution is preferred.
Changes since v1:
- Change local variable type to bool as well, use boolean values in
code
- Also change prototype of open drain/open source setting functions
since they are only called from _gpiod_set_raw_value()
This probably calls for a larger booleanization of gpiolib, but let's
keep that for a latter change - right now we need to address the issue
of non-boolean values returned by drivers.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The current ACPI GPIO event handling code was never tested against real
hardware with functioning GPIO triggered events (at the time such hardware
wasn't available). Thus it misses certain things like requesting the GPIOs
properly, passing correct flags to the interrupt handler and so on.
This patch reworks ACPI GPIO event handling so that we:
1) Use struct acpi_gpio_event for all GPIO signaled events.
2) Switch to use GPIO descriptor API and request GPIOs by calling
gpiochip_request_own_desc() that we added in a previous patch.
3) Pass proper flags from ACPI GPIO resource to request_threaded_irq().
Also instead of open-coding the _AEI iteration loop we can use
acpi_walk_resources(). This simplifies the code a bit and fixes memory leak
that was caused by missing kfree() for buffer returned by
acpi_get_event_resources().
Since the remove path now calls gpiochip_free_own_desc() which takes GPIO
spinlock we need to call acpi_gpiochip_remove() outside of that lock
(analogous to acpi_gpiochip_add() path where the lock is released before
those funtions are called).
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
In order to consolidate _Exx, _Lxx and _EVT to use the same structure make
the structure name to reflect that we are dealing with any event, not just
_EVT.
This is just rename, no functional changes.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
We are going to add more ACPI specific data to accompany GPIO chip so
instead of allocating it per each use-case we allocate it once when
acpi_gpiochip_add() is called and release it when acpi_gpiochip_remove() is
called.
Doing this allows us to add more ACPI specific data by merely adding new
fields to struct acpi_gpio_chip.
In addition we embed evt_pins member directly to the structure instead of
having it as a pointer. This simplifies the code a bit since we don't need
to check against NULL.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Sometimes it is useful to allow GPIO chips themselves to request GPIOs they
own through gpiolib API. One use case is ACPI ASL code that should be able
to toggle GPIOs through GPIO operation regions.
We can't use gpio_request() because it will pin the module to the kernel
forever (it calls try_module_get()). To solve this we move module refcount
manipulation to gpiod_request() and let __gpiod_request() handle the actual
request. This changes the sequence a bit as now try_module_get() is called
outside of gpio_lock (I think this is safe, try_module_get() handles
serialization it needs already).
Then we provide gpiolib internal functions gpiochip_request/free_own_desc()
that do the same as gpio_request() but don't manipulate module refrence
count. This allows the GPIO chip driver to request and free descriptors it
owns without being pinned to the kernel forever.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>