This makes the driver use the data pointer added to the gpio_chip
to store a pointer to the state container instead of relying on
container_of().
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Infrastructural changes:
- In struct gpio_chip, rename the .dev node to .parent to better reflect
the fact that this is not the GPIO struct device abstraction. We will
add that soon so this would be totallt confusing.
- It was noted that the driver .get_value() callbacks was
sometimes reporting negative -ERR values to the gpiolib core, expecting
them to be propagated to consumer gpiod_get_value() and gpio_get_value()
calls. This was not happening, so as there was a mess of drivers
returning negative errors and some returning "anything else than zero"
to indicate that a line was active. As some would have bit 31 set to
indicate "line active" it clashed with negative error codes. This is
fixed by the largeish series clamping values in all drivers with
!!value to [0,1] and then augmenting the code to propagate error codes
to consumers. (Includes some ACKed patches in other subsystems.)
- Add a void *data pointer to struct gpio_chip. The container_of() design
pattern is indeed very nice, but we want to reform the struct gpio_chip
to be a non-volative, stateless business, and keep states internal to
the gpiolib to be able to hold on to the state when adding a proper
userspace ABI (character device) further down the road. To achieve this,
drivers need a handle at the internal state that is not dependent on
their struct gpio_chip() so we add gpiochip_add_data() and
gpiochip_get_data() following the pattern of many other subsystems.
All the "use gpiochip data pointer" patches transforms drivers to this
scheme.
- The Generic GPIO chip header has been merged into the general
<linux/gpio/driver.h> header, and the custom header for that removed.
Instead of having a separate mm_gpio_chip struct for these generic
drivers, merge that into struct gpio_chip, simplifying the code and
removing the need for separate and confusing includes.
Misc improvements:
- Stabilize the way GPIOs are looked up from the ACPI legacy
specification.
- Incremental driver features for PXA, PCA953X, Lantiq (patches from the
OpenWRT community), RCAR, Zynq, PL061, 104-idi-48
New drivers:
- Add a GPIO chip to the ALSA SoC AC97 driver.
- Add a new Broadcom NSP SoC driver (this lands in the pinctrl dir, but
the branch is merged here too to account for infrastructural changes).
- The sx150x driver now supports the sx1502.
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Merge tag 'gpio-v4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO updates from Linus Walleij:
"Here is the bulk of GPIO changes for v4.5.
Notably there are big refactorings mostly by myself, aimed at getting
the gpio_chip into a shape that makes me believe I can proceed to
preserve state for a proper userspace ABI (character device) that has
already been proposed once, but resulted in the feedback that I need
to go back and restructure stuff. So I've been restructuring stuff.
On the way I ran into brokenness (return code from the get_value()
callback) and had to fix it. Also, refactored generic GPIO to be
simpler.
Some of that is still waiting to trickle down from the subsystems all
over the kernel that provide random gpio_chips, I've touched every
single GPIO driver in the kernel now, oh man I didn't know I was
responsible for so much...
Apart from that we're churning along as usual.
I took some effort to test and retest so it should merge nicely and we
shook out a couple of bugs in -next.
Infrastructural changes:
- In struct gpio_chip, rename the .dev node to .parent to better
reflect the fact that this is not the GPIO struct device
abstraction. We will add that soon so this would be totallt
confusing.
- It was noted that the driver .get_value() callbacks was sometimes
reporting negative -ERR values to the gpiolib core, expecting them
to be propagated to consumer gpiod_get_value() and gpio_get_value()
calls. This was not happening, so as there was a mess of drivers
returning negative errors and some returning "anything else than
zero" to indicate that a line was active. As some would have bit
31 set to indicate "line active" it clashed with negative error
codes. This is fixed by the largeish series clamping values in all
drivers with !!value to [0,1] and then augmenting the code to
propagate error codes to consumers. (Includes some ACKed patches
in other subsystems.)
- Add a void *data pointer to struct gpio_chip. The container_of()
design pattern is indeed very nice, but we want to reform the
struct gpio_chip to be a non-volative, stateless business, and keep
states internal to the gpiolib to be able to hold on to the state
when adding a proper userspace ABI (character device) further down
the road. To achieve this, drivers need a handle at the internal
state that is not dependent on their struct gpio_chip() so we add
gpiochip_add_data() and gpiochip_get_data() following the pattern
of many other subsystems. All the "use gpiochip data pointer"
patches transforms drivers to this scheme.
- The Generic GPIO chip header has been merged into the general
<linux/gpio/driver.h> header, and the custom header for that
removed. Instead of having a separate mm_gpio_chip struct for
these generic drivers, merge that into struct gpio_chip,
simplifying the code and removing the need for separate and
confusing includes.
Misc improvements:
- Stabilize the way GPIOs are looked up from the ACPI legacy
specification.
- Incremental driver features for PXA, PCA953X, Lantiq (patches from
the OpenWRT community), RCAR, Zynq, PL061, 104-idi-48
New drivers:
- Add a GPIO chip to the ALSA SoC AC97 driver.
- Add a new Broadcom NSP SoC driver (this lands in the pinctrl dir,
but the branch is merged here too to account for infrastructural
changes).
- The sx150x driver now supports the sx1502"
* tag 'gpio-v4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (220 commits)
gpio: generic: make bgpio_pdata always visible
gpiolib: fix chip order in gpio list
gpio: mpc8xxx: Do not use gpiochip_get_data() in mpc8xxx_gpio_save_regs()
gpio: mm-lantiq: Do not use gpiochip_get_data() in ltq_mm_save_regs()
gpio: brcmstb: Allow building driver for BMIPS_GENERIC
gpio: brcmstb: Set endian flags for big-endian MIPS
gpio: moxart: fix build regression
gpio: xilinx: Do not use gpiochip_get_data() in xgpio_save_regs()
leds: pca9532: use gpiochip data pointer
leds: tca6507: use gpiochip data pointer
hid: cp2112: use gpiochip data pointer
bcma: gpio: use gpiochip data pointer
avr32: gpio: use gpiochip data pointer
video: fbdev: via: use gpiochip data pointer
gpio: pch: Optimize pch_gpio_get()
Revert "pinctrl: lantiq: Implement gpio_chip.to_irq"
pinctrl: nsp-gpio: use gpiochip data pointer
pinctrl: vt8500-wmt: use gpiochip data pointer
pinctrl: exynos5440: use gpiochip data pointer
pinctrl: at91-pio4: use gpiochip data pointer
...
As we want gpio_chip .get() calls to be able to return negative
error codes and propagate to drivers, we need to go over all
drivers and make sure their return values are clamped to [0,1].
We do this by using the ret = !!(val) design pattern.
Cc: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
The name .dev in a struct is normally reserved for a struct device
that is let us say a superclass to the thing described by the struct.
struct gpio_chip stands out by confusingly using a struct device *dev
to point to the parent device (such as a platform_device) that
represents the hardware. As we want to give gpio_chip:s real devices,
this is not working. We need to rename this member to parent.
This was done by two coccinelle scripts, I guess it is possible to
combine them into one, but I don't know such stuff. They look like
this:
@@
struct gpio_chip *var;
@@
-var->dev
+var->parent
and:
@@
struct gpio_chip var;
@@
-var.dev
+var.parent
and:
@@
struct bgpio_chip *var;
@@
-var->gc.dev
+var->gc.parent
Plus a few instances of bgpio that I couldn't figure out how
to teach Coccinelle to rewrite.
This patch hits all over the place, but I *strongly* prefer this
solution to any piecemal approaches that just exercise patch
mechanics all over the place. It mainly hits drivers/gpio and
drivers/pinctrl which is my own backyard anyway.
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Rafał Miłecki <zajec5@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Alek Du <alek.du@intel.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Most interrupt flow handlers do not use the irq argument. Those few
which use it can retrieve the irq number from the irq descriptor.
Remove the argument.
Search and replace was done with coccinelle and some extra helper
scripts around it. Thanks to Julia for her help!
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
irq is incremented for no value in the for loop. Remove it.
Search and update was done with coccinelle and the invaluable help of
Julia Lawall.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
set_irq_flags is ARM specific with custom flags which have genirq
equivalents. Convert drivers to use the genirq interfaces directly, so we
can kill off set_irq_flags. The translation of flags is as follows:
IRQF_VALID -> !IRQ_NOREQUEST
IRQF_PROBE -> !IRQ_NOPROBE
IRQF_NOAUTOEN -> IRQ_NOAUTOEN
For IRQs managed by an irqdomain, the irqdomain core code handles clearing
and setting IRQ_NOREQUEST already, so there is no need to do this in
.map() functions and we can simply remove the set_irq_flags calls. Some
users also modify IRQ_NOPROBE and this has been maintained although it
is not clear that is really needed. There appears to be a great deal of
blind copy and paste of this code.
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Convert SA11x0 (Neponset, SA1111, and UCB1x00 code) to use the new
irq_set_chained_handler_and_data() helper.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/E1Z4yzx-0002S6-7p@rmk-PC.arm.linux.org.uk
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
this remove all reference to gpio_remove retval in all driver
except pinctrl and gpio. the same thing is done for gpio and
pinctrl in two different patches.
Signed-off-by: Abdoulaye Berthe <berthe.ab@gmail.com>
Acked-by: Michael Büsch <m@bues.ch>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Use SIMPLE_DEV_PM_OPS macro in order to make the code simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Fix to return a negative error code in the irq alloc error handling
case instead of 0, as done elsewhere in this function.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Error handling is on-its-head in this function. After invoking a function we
should examine the return code and return the error value if there was one.
Instead, this function checks for success and goes onto provide functionality
if success was received. Not so bad in a simple function like this, but in
a more complex one this could end up drowning in curly brackets.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Add CONFIG_PM_SLEEP to suspend/resume functions to fix the build
warnings when CONFIG_PM_SLEEP is not selected. This is because
sleep PM callbacks defined by SET_SYSTEM_SLEEP_PM_OPS are only used
when the CONFIG_PM_SLEEP is enabled.
drivers/mfd/ucb1x00-core.c:672:12: warning: 'ucb1x00_suspend' defined but not used [-Wunused-function]
drivers/mfd/ucb1x00-core.c:704:12: warning: 'ucb1x00_resume' defined but not used [-Wunused-function]
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Add genirq wakeup support for the ucb1x00 device. This allows an
attached gpio_keys driver to wakeup the system. Touchscreen is also
possible.
When there are no wakeup sources, ask the platform to assert the reset
signal to avoid any unexpected behaviour; this also puts the reset
signal at the right level when power is removed from the device.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Convert the ucb1x00 driver to use genirq's interrupt services, rather
than its own private implementation. This allows a wider range of
drivers to use the GPIO interrupts (such as the gpio_keys driver)
without being aware of the UCB1x00's private IRQ system.
This prevents the UCB1x00 core driver from being built as a module,
so adjust the configuration to add that restriction.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Convert the ucb1x00-core driver to use dev_pm_ops rather than the legacy
members in the mcp driver.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The ucb1x00-core was leaving the mcp clock enabled indefinitely after
probe. This needlessly wastes power. Add the necessary disables to
ensure that the clock remains off when we don't need it.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ucb1x00_enable() and ucb1x00_disable() are used for power saving on the
SIB interface, allowing the host supplied clock to be disabled when not
required. We require drivers which access the ucb1x00 to ensure that
they have enabled the clock prior to accessing the device, and they
should disable it once they're done.
As we don't expect gpiolib users to be aware of this detail, we must
make these calls in the gpiolib interfaces. Add them.
Also add them to the resume method, which needs to re-establish the
GPIO pin settings.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cosmetic patch to scan the list of drivers in the order that the drivers
are registered, rather than the reverse order. This avoids surprises
when drivers get probed in the reverse order, and input devices get
registered in a different order due to bind/unbind than from boot.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Register the gpio device with proper .owner and .dev elements set
appropraitely.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Clean up the device handling so we can use the struct device sanely.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Convert the ucb1x00 driver to use mutexes rather than the depreciated
semaphores for exclusive access to the ADC.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add a .owner initializer to the UCB1x00 mcp driver structure, and
set an appropriate module alias to identify this driver.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Provide a way to handle the software controlled ucb1x00 reset signal
from the ucb1x00-core driver without having to code platform specifics
into these drivers.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Nothing in this driver requires anything from the machine/platform
headers, so remove this needless header file.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch taken from 5dd7bf59e0 (ARM: sa11x0: Implement autoloading of codec
and codec pdata for mcp bus.) by Jochen Friedrich <jochen@scram.de>.
This adds just the codec data part of the patch.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The dma_device_t variables are only ever written to by mcp-sa11x0 and
never read. As the old SA11x0 DMA support will be removed, remove
these so that it no longer depends on the old SA11x0 DMA definitions.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
gpiolib drivers should first set the output data before setting the
direction to avoid putting glitches on an output signal. As an
additional bonus, we tweak the code to avoid unnecessary register
writes to the output and direction registers if they have no need
to be updated.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We were not restoring the UCB1x00 gpio output data on resume, resulting
in incorrect GPIO output data after a resume. Add the missing register
write.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This reverts commit 5dd7bf59e0.
Conflicts:
scripts/mod/file2alias.c
This change is wrong on many levels. First and foremost, it causes a
regression. On boot on Assabet, which this patch gives a codec id of
'ucb1x00', it gives:
ucb1x00 ID not found: 1005
0x1005 is a valid ID for the UCB1300 device.
Secondly, this patch is way over the top in terms of complexity. The
only device which has been seen to be connected with this MCP code is
the UCB1x00 (UCB1200, UCB1300 etc) devices, and they all use the same
driver. Adding a match table, requiring the codec string to match the
hardware ID read out of the ID register, etc is completely over the top
when we can just read the hardware ID register.
This patch fixes a build failure[1], by adding the missing semaphore.h include
References:
[1] http://kisskb.ellerman.id.au/kisskb/buildresult/2234322/
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
After m68k's task_thread_info() doesn't refer to current,
it's possible to remove sched.h from interrupt.h and not break m68k!
Many thanks to Heiko Carstens for allowing this.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
When ISA_DMA_API is unset, we're not implementing the ISA DMA API,
so there's no point in publishing the prototypes via asm/dma.h, nor
including the machine dependent parts of that API.
This allows us to remove a lot of mach/dma.h files which don't contain
any useful code. Unfortunately though, some platforms put their own
private non-ISA definitions into mach/dma.h, so we leave these behind
and fix the appropriate #include statments.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Remove includes of asm/hardware.h in addition to asm/arch/hardware.h.
Then, since asm/hardware.h only exists to include asm/arch/hardware.h,
update everything to directly include asm/arch/hardware.h and remove
asm/hardware.h.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
struct class_device is going away, this converts the code to use struct
device instead.
Signed-off-by: Tony Jones <tonyj@suse.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc).
Here is a short excerpt of the semantic patch performing
this transformation:
@@
type T2;
expression x;
identifier f,fld;
expression E;
expression E1,E2;
expression e1,e2,e3,y;
statement S;
@@
x =
- kmalloc
+ kzalloc
(E1,E2)
... when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\)
- memset((T2)x,0,E1);
@@
expression E1,E2,E3;
@@
- kzalloc(E1 * E2,E3)
+ kcalloc(E1,E2,E3)
[akpm@linux-foundation.org: get kcalloc args the right way around]
Signed-off-by: Yoann Padioleau <padator@wanadoo.fr>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Bryan Wu <bryan.wu@analog.com>
Acked-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Dave Airlie <airlied@linux.ie>
Acked-by: Roland Dreier <rolandd@cisco.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Acked-by: Pierre Ossman <drzeus-list@drzeus.cx>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Greg KH <greg@kroah.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
Patch from Pavel Machek
From: Dirk Opfer <Dirk@Opfer-Online.de>
Fix ucb initialization on collie. Wrong frequency was used and that
led to things not working quite correctly. (I had to actually disable
checks in my tree to get it to boot). It now includes all the
neccessary parts to get it to compile :-).
Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
While reviewing the IRQ autoprobing code i found the attached buglet.
probe_irq_on()/off() calls must always be in pairs, because the generic IRQ
code uses a global semaphore to serialize all autoprobing activites.
(which does make sense) The ARM code's probe_irq_*() implementation does
not do this, but if this driver is ever used on another platform, this bug
might bite.
(It probably does not trigger in practice, because a zero probing mask
returned should be rare - but still.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Some ARM platforms have the ability to program the interrupt controller to
detect various interrupt edges and/or levels. For some platforms, this is
critical to setup correctly, particularly those which the setting is dependent
on the device.
Currently, ARM drivers do (eg) the following:
err = request_irq(irq, ...);
set_irq_type(irq, IRQT_RISING);
However, if the interrupt has previously been programmed to be level sensitive
(for whatever reason) then this will cause an interrupt storm.
Hence, if we combine set_irq_type() with request_irq(), we can then safely set
the type prior to unmasking the interrupt. The unfortunate problem is that in
order to support this, these flags need to be visible outside of the ARM
architecture - drivers such as smc91x need these flags and they're
cross-architecture.
Finally, the SA_TRIGGER_* flag passed to request_irq() should reflect the
property that the device would like. The IRQ controller code should do its
best to select the most appropriate supported mode.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Patch from Nicolas Pitre
drivers/mfd/ucb1x00-core.c: In function 'ucb1x00_probe':
drivers/mfd/ucb1x00-core.c:482: error: 'ucb1x00_class' undeclared (first use in this function)
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
