gpio: mlxbf2: Convert to immutable irq_chip

Convert the driver to immutable irq-chip with a bit of
intuition.

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

gpio: mlxbf2: Use generic_handle_irq_safe()

On PREEMPT_RT enabled kernels the demultiplex interrupt handler is force
threaded and runs with interrupts enabled. The invocation of
generic_handle_irq() with interrupts enabled triggers a lockdep warning due
to a non-irq safe lock acquisition.

Instead of disabling interrupts on the driver level, use
generic_handle_domain_irq_safe().

[ tglx: Split out from combo patch ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/YnkfWFzvusFFktSt@linutronix.de

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: mlxbf2: Introduce IRQ support

Introduce standard IRQ handling in the gpio-mlxbf2.c
driver.

Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

gpio: mlxbf2.c: Add check for bgpio_init failure

Add a check if bgpio_init fails.

Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

gpio: mlxbf2: Use DEFINE_RES_MEM_NAMED() helper macro

Use DEFINE_RES_MEM_NAMED() to save a couple of lines of code, which makes
the code a bit shorter and easier to read.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Asmaa Mnebhi <asmaa@nvidia.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

gpio: mlxbf2: Use devm_platform_ioremap_resource()

Simplify the platform_get_resource() and devm_ioremap_resource()
calls with devm_platform_ioremap_resource().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Asmaa Mnebhi <asmaa@nvidia.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

gpio: mlxbf2: Drop wrong use of ACPI_PTR()

ACPI_PTR() is more harmful than helpful. For example, in this case
if CONFIG_ACPI=n, the ID table left unused which is not what we want.

Instead of adding ifdeffery here and there, drop ACPI_PTR() and
replace acpi.h with mod_devicetable.h.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Asmaa Mnehi <asmaa@nvidia.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

gpio: mlxbf2: Convert to device PM ops

Convert driver to use modern device PM ops interface.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Asmaa Mnebhi <asmaa@nvidia.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

gpio: gpio-mlxbf2.c: Provide __releases() annotation to stop confusing Sparse

Sparse cannot peer into other functions to see when and if locks are
acquired and released, thus it simply warns that a 'context imbalance'
is detected instead. Let's be kind to Sparse and let it know that
this behaviour is intentional.

drivers/gpio/gpio-mlxbf2.c:125:12: warning: context imbalance in 'mlxbf2_gpio_lock_acquire' - different lock contexts for basic block
drivers/gpio/gpio-mlxbf2.c:151:13: warning: context imbalance in 'mlxbf2_gpio_lock_release' - unexpected unlock

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Asmaa Mnebhi <asmaa@mellanox.com>
Cc: Asmaa Mnebhi <Asmaa@mellanox.com>
Link: https://lore.kernel.org/r/20200630133345.2232932-11-lee.jones@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

gpio: gpio-mlxbf2: Tell the compiler that ACPI functions may not be use

... as is the case when !CONFIG_ACPI.

Fixes the following W=1 kernel build warning:

drivers/gpio/gpio-mlxbf2.c:312:36: warning: ‘mlxbf2_gpio_acpi_match’ defined but not used [-Wunused-const-variable=]
312 | static const struct acpi_device_id mlxbf2_gpio_acpi_match[] = {
| ^~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Asmaa Mnebhi <asmaa@mellanox.com>
Cc: Asmaa Mnebhi <Asmaa@mellanox.com>
Link: https://lore.kernel.org/r/20200630133345.2232932-10-lee.jones@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

gpio: mlxbf2: Fix sleeping while holding spinlock

mutex_lock() can sleep, don't call mutex_lock() while holding spin_lock.

Fixes: bc0ae0e737f5 ("gpio: add driver for Mellanox BlueField 2 GPIO controller")
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: asmaa@mellanox.com
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

gpio: mlxbf2: fix return value check in mlxbf2_gpio_get_lock_res()

In case of error, the function devm_ioremap() returns NULL pointer not
ERR_PTR(). The IS_ERR() test in the return value check should be
replaced with NULL test.

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Link: https://lore.kernel.org/r/20200427110829.154785-1-weiyongjun1@huawei.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

gpio: mlxbf2: remove unused including <linux/version.h>

Remove including <linux/version.h> that don't need it.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20200408070832.137037-1-yuehaibing@huawei.com
Acked-by: Asmaa Mnebhi <Asmaa@mellanox.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

gpio: add driver for Mellanox BlueField 2 GPIO controller

This patch adds support for the GPIO controller used by
Mellanox BlueField 2 SOCs.

Signed-off-by: Asmaa Mnebhi <Asmaa@mellanox.com>
Link: https://lore.kernel.org/r/1680de9eb6d2b8855228dde9a2dd065f0dcbe1fb.1583182325.git.Asmaa@mellanox.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>