gpio: ixp4xx: Handle clock output on pin 14 and 15

This makes it possible to provide basic clock output on pins
14 and 15. The clocks are typically used by random electronics,
not modeled in the device tree, so they just need to be provided
on request.

In order to not disturb old systems that require that the
hardware defaults are kept in the clock setting bits, we only
manipulate these if either device tree property is present.
Once we know a device needs one of the clocks we can set it
in the device tree.

Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

gpio: ixp4xx: remove redundant of_match_ptr()

The driver depends on CONFIG_OF, so it is not necessary to use
of_match_ptr() here.

Even for drivers that do not depend on CONFIG_OF, it's almost always
better to leave out the of_match_ptr(), since the only thing it can
possibly do is to save a few bytes of .text if a driver can be used both
with and without it. Hence we remove of_match_ptr().

Signed-off-by: Zhu Wang <wangzhu9@huawei.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

gpio: ixp4xx: Use devm_platform_ioremap_resource()

Convert platform_get_resource(),devm_ioremap_resource() to a single
call to devm_platform_ioremap_resource(), as this is exactly what this
function does.

Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

gpio: ixp4xx: Make irqchip immutable

This turns the IXP4xx GPIO irqchip into an immutable
irqchip, a bit different from the standard template due
to being hierarchical.

Tested on the IXP4xx which uses drivers/ata/pata_ixp4xx_cf.c
for a rootfs on compact flash with IRQs from this GPIO
block to the CF ATA controller.

Cc: Marc Zyngier <maz@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

irq/gpio: ixp4xx: Drop boardfile probe path

The boardfiles for IXP4xx have been deleted. Delete all the
quirks and code dealing with that boot path and rely solely on
device tree boot.

Fix some missing static keywords that the kernel test robot
was complaining about while we're at it.

Cc: Bartosz Golaszewski <brgl@bgdev.pl>
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

gpio: use raw spinlock for gpio chip shadowed data

In case of PREEMPT_RT, there is a raw_spinlock -> spinlock dependency
as the lockdep report shows.

__irq_set_handler
irq_get_desc_buslock
__irq_get_desc_lock
raw_spin_lock_irqsave(&desc->lock, *flags); // raw spinlock get here
__irq_do_set_handler
mask_ack_irq
dwapb_irq_ack
spin_lock_irqsave(&gc->bgpio_lock, flags); // sleep able spinlock
irq_put_desc_busunlock

Replace with a raw lock to avoid BUGs. This lock is only used to access
registers, and It's safe to replace with the raw lock without bad
influence.

[ 15.090359][ T1] =============================
[ 15.090365][ T1] [ BUG: Invalid wait context ]
[ 15.090373][ T1] 5.10.59-rt52-00983-g186a6841c682-dirty #3 Not tainted
[ 15.090386][ T1] -----------------------------
[ 15.090392][ T1] swapper/0/1 is trying to lock:
[ 15.090402][ T1] 70ff00018507c188 (&gc->bgpio_lock){....}-{3:3}, at: _raw_spin_lock_irqsave+0x1c/0x28
[ 15.090470][ T1] other info that might help us debug this:
[ 15.090477][ T1] context-{5:5}
[ 15.090485][ T1] 3 locks held by swapper/0/1:
[ 15.090497][ T1] #0: c2ff0001816de1a0 (&dev->mutex){....}-{4:4}, at: __device_driver_lock+0x98/0x104
[ 15.090553][ T1] #1: ffff90001485b4b8 (irq_domain_mutex){+.+.}-{4:4}, at: irq_domain_associate+0xbc/0x6d4
[ 15.090606][ T1] #2: 4bff000185d7a8e0 (lock_class){....}-{2:2}, at: _raw_spin_lock_irqsave+0x1c/0x28
[ 15.090654][ T1] stack backtrace:
[ 15.090661][ T1] CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.10.59-rt52-00983-g186a6841c682-dirty #3
[ 15.090682][ T1] Hardware name: Horizon Robotics Journey 5 DVB (DT)
[ 15.090692][ T1] Call trace:
......
[ 15.090811][ T1] _raw_spin_lock_irqsave+0x1c/0x28
[ 15.090828][ T1] dwapb_irq_ack+0xb4/0x300
[ 15.090846][ T1] __irq_do_set_handler+0x494/0xb2c
[ 15.090864][ T1] __irq_set_handler+0x74/0x114
[ 15.090881][ T1] irq_set_chip_and_handler_name+0x44/0x58
[ 15.090900][ T1] gpiochip_irq_map+0x210/0x644

Signed-off-by: Schspa Shi <schspa@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Doug Berger <opendmb@gmail.com>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

gpio: ixp4xx: Detect special machines by compatible

There are some special clock amendments for two machines
formerly detected by their machine_is() boardfile macro.

They are now migrated to device tree so use
of_machine_is_compatible() instead.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

gpio/ixp4xx: Register the base PA instead of its VA in fwnode

Do not expose the base VA (it appears in debugfs). Instead,
record the PA, which at least can be used to precisely identify
the associated irqchip and domain.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

gpio: ixp4xx: Convert to hierarchical GPIOLIB_IRQCHIP

This modifies the IXP4xx driver to use the new helpers
to handle the remapping of parent to child hardware irqs
in the gpiolib core.

This pulls the majority of the code out of the driver
and use the generic code in gpiolib.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Lina Iyer <ilina@codeaurora.org>
Cc: Jon Hunter <jonathanh@nvidia.com>
Cc: Sowjanya Komatineni <skomatineni@nvidia.com>
Cc: Bitan Biswas <bbiswas@nvidia.com>
Cc: linux-tegra@vger.kernel.org
Cc: Thierry Reding <treding@nvidia.com>
Cc: Brian Masney <masneyb@onstation.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20190808123242.5359-2-linus.walleij@linaro.org

gpio/ixp4xx: Register the base PA instead of its VA in fwnode

Do not expose the base VA (it appears in debugfs). Instead,
record the PA, which at least can be used to precisely identify
the associated irqchip and domain.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <maz@kernel.org>

gpio: ixp4xx: remove redundant dev_err message

devm_ioremap_resource already contains error message, so remove
the redundant dev_err message

Signed-off-by: Ding Xiang <dingxiang@cmss.chinamobile.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

gpio: ixp4xx: Use irq_domain_translate_twocell()

Use standard functions. Eventually we will be able to drop all
checks and just assign irq_domain_translate_twocell() to this
callback.

Cc: Brian Masney <masneyb@onstation.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

gpio: ixp4xx: Add OF probing support

This adds device tree probe and registration support for
the IXP4xx GPIO driver.

Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

gpio: ixp4xx: Add driver for the IXP4xx GPIO

This adds a driver for the IXP4xx GPIO block found in
the Intel XScale IXP4xx systems.

The GPIO part of this block is pretty straight-forward and
just uses the generic MMIO GPIO library.

The irqchip side of this driver is hierarchical where
the main irqchip will receive a processed level trigger
in response to the edge detector of the GPIO block,
so for this reason the v2 version of the irqdomain API
is used (as well as in the parent IXP4xx irqchip) and
masking, unmasking and setting up the type on IRQ
happens on several levels.

Currently this GPIO controller will grab the parent
irqdomain using a special function, but as the platform
move toward device tree probing, this will not be needed:
we can just look up the parent irqdomain from the device
tree.

Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>