pinctrl: meditatek: Startup with the IRQs disabled

If the system is restarted via kexec(), the peripherals do not start
with a known state.

If the previous system had enabled an IRQs we will receive unexected
IRQs that can lock the system.

[ 28.109251] watchdog: BUG: soft lockup - CPU#0 stuck for 26s!
[swapper/0:0]
[ 28.109263] Modules linked in:
[ 28.109273] CPU: 0 PID: 0 Comm: swapper/0 Not tainted
5.15.79-14458-g4b9edf7b1ac6 #1 9f2e76613148af94acccd64c609a552fb4b4354b
[ 28.109284] Hardware name: Google Elm (DT)
[ 28.109290] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS
BTYPE=--)
[ 28.109298] pc : __do_softirq+0xa0/0x388
[ 28.109309] lr : __do_softirq+0x70/0x388
[ 28.109316] sp : ffffffc008003ee0
[ 28.109321] x29: ffffffc008003f00 x28: 000000000000000a x27:
0000000000000080
[ 28.109334] x26: 0000000000000001 x25: ffffffefa7b350c0 x24:
ffffffefa7b47480
[ 28.109346] x23: ffffffefa7b3d000 x22: 0000000000000000 x21:
ffffffefa7b0fa40
[ 28.109358] x20: ffffffefa7b005b0 x19: ffffffefa7b47480 x18:
0000000000065b6b
[ 28.109370] x17: ffffffefa749c8b0 x16: 000000000000018c x15:
00000000000001b8
[ 28.109382] x14: 00000000000d3b6b x13: 0000000000000006 x12:
0000000000057e91
[ 28.109394] x11: 0000000000000000 x10: 0000000000000000 x9 :
ffffffefa7b47480
[ 28.109406] x8 : 00000000000000e0 x7 : 000000000f424000 x6 :
0000000000000000
[ 28.109418] x5 : ffffffefa7dfaca0 x4 : ffffffefa7dfadf0 x3 :
000000000000000f
[ 28.109429] x2 : 0000000000000000 x1 : 0000000000000100 x0 :
0000000001ac65c5
[ 28.109441] Call trace:
[ 28.109447] __do_softirq+0xa0/0x388
[ 28.109454] irq_exit+0xc0/0xe0
[ 28.109464] handle_domain_irq+0x68/0x90
[ 28.109473] gic_handle_irq+0xac/0xf0
[ 28.109480] call_on_irq_stack+0x28/0x50
[ 28.109488] do_interrupt_handler+0x44/0x58
[ 28.109496] el1_interrupt+0x30/0x58
[ 28.109506] el1h_64_irq_handler+0x18/0x24
[ 28.109512] el1h_64_irq+0x7c/0x80
[ 28.109519] arch_local_irq_enable+0xc/0x18
[ 28.109529] default_idle_call+0x40/0x140
[ 28.109539] do_idle+0x108/0x290
[ 28.109547] cpu_startup_entry+0x2c/0x30
[ 28.109554] rest_init+0xe8/0xf8
[ 28.109562] arch_call_rest_init+0x18/0x24
[ 28.109571] start_kernel+0x338/0x42c
[ 28.109578] __primary_switched+0xbc/0xc4
[ 28.109588] Kernel panic - not syncing: softlockup: hung tasks

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Link: https://lore.kernel.org/r/20221122-mtk-pinctrl-v1-1-bedf5655a3d2@chromium.org
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: mediatek: Export debounce time tables

The kernel test robot complains that in certain combinations
when building the Mediatek drivers as modules we lack some
debounce table symbols, so export them.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: e1ff91f9d230 ("pinctrl: mediatek: Fix EINT pins input debounce time configuration")
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: mediatek: Fix EINT pins input debounce time configuration

The External Interrupt Controller (EINTC) on all of the supported
MediaTek SoCs does support input debouncing, but not all of them
index the debounce time values (DBNC_SETTING registers) the same way.

Before this change, in some cases, as an example, requesting a debounce
time of 16 milliseconds would mistakenly set the relative DBNC_SETTING
register to 0x2, resulting in a way shorter debounce time of 500uS.

To fix the aforementioned issue, define three different debounce_time
arrays, reflecting the correct register index for each value and for
each register index variant, and make sure that each SoC pinctrl
driver uses the right one.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20221111094106.18486-1-angelogioacchino.delregno@collabora.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: Bulk conversion to generic_handle_domain_irq()

Wherever possible, replace constructs that match either
generic_handle_irq(irq_find_mapping()) or
generic_handle_irq(irq_linear_revmap()) to a single call to
generic_handle_domain_irq().

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>

pinctrl: mediatek: Fix trigger type setting follow for unexpected interrupt

When flipping the polarity will be generated interrupt under certain
circumstances, but GPIO external signal has not changed.
Then, mask the interrupt before polarity setting, and clear the
unexpected interrupt after trigger type setting completed.

Remove mtk_eint_flip_edge: because mtk_eint_unmask already calls it.

Signed-off-by: Hailong Fan <hailong.fan@mediatek.com>
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>
Link: https://lore.kernel.org/r/20210125041753.2214-1-hailong.fan@mediatek.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: mediatek: make MediaTek pinctrl v2 driver ready for buidling loadable module

In the future we want to be able to build the MediaTek pinctrl driver,
based on paris, as kernel module. This patch allows pinctrl-paris.c, the
external interrupt controller mtk-eint.c, and pinctrl-mtk-common-v2.c to
be loadable as module.

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Light Hsieh <light.hsieh@mediatek.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Link: https://lore.kernel.org/r/9feeb04805e5a406fe22a92e3f280abda39ddda4.1586289920.git.sean.wang@mediatek.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: mediatek: Update cur_mask in mask/mask ops

During suspend/resume, mtk_eint_mask may be called while
wake_mask is active. For example, this happens if a wake-source
with an active interrupt handler wakes the system:
irq/pm.c:irq_pm_check_wakeup would disable the interrupt, so
that it can be handled later on in the resume flow.

However, this may happen before mtk_eint_do_resume is called:
in this case, wake_mask is loaded, and cur_mask is restored
from an older copy, re-enabling the interrupt, and causing
an interrupt storm (especially for level interrupts).

Step by step, for a line that has both wake and interrupt enabled:
1. cur_mask[irq] = 1; wake_mask[irq] = 1; EINT_EN[irq] = 1 (interrupt
enabled at hardware level)
2. System suspends, resumes due to that line (at this stage EINT_EN
== wake_mask)
3. irq_pm_check_wakeup is called, and disables the interrupt =>
EINT_EN[irq] = 0, but we still have cur_mask[irq] = 1
4. mtk_eint_do_resume is called, and restores EINT_EN = cur_mask, so
it reenables EINT_EN[irq] = 1 => interrupt storm as the driver
is not yet ready to handle the interrupt.

This patch fixes the issue in step 3, by recording all mask/unmask
changes in cur_mask. This also avoids the need to read the current
mask in eint_do_suspend, and we can remove mtk_eint_chip_read_mask
function.

The interrupt will be re-enabled properly later on, sometimes after
mtk_eint_do_resume, when the driver is ready to handle it.

Fixes: 58a5e1b64bb0 ("pinctrl: mediatek: Implement wake handler and suspend resume")
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Acked-by: Sean Wang <sean.wang@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: mediatek: Ignore interrupts that are wake only during resume

Before suspending, mtk-eint would set the interrupt mask to the
one in wake_mask. However, some of these interrupts may not have a
corresponding interrupt handler, or the interrupt may be disabled.

On resume, the eint irq handler would trigger nevertheless,
and irq/pm.c:irq_pm_check_wakeup would be called, which would
try to call irq_disable. However, if the interrupt is not enabled
(irqd_irq_disabled(&desc->irq_data) is true), the call does nothing,
and the interrupt is left enabled in the eint driver.

Especially for level-sensitive interrupts, this will lead to an
interrupt storm on resume.

If we detect that an interrupt is only in wake_mask, but not in
cur_mask, we can just mask it out immediately (as mtk_eint_resume
would do anyway at a later stage in the resume sequence, when
restoring cur_mask).

Fixes: bf22ff45bed6 ("genirq: Avoid unnecessary low level irq function calls")
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Acked-by: Sean Wang <sean.wang@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: Include <linux/gpio/driver.h> nothing else

These drivers are GPIO drivers, and the do not need to use the
legacy header in <linux/gpio.h>, go directly for
<linux/gpio/driver.h> instead.

Replace any use of GPIOF_* with 0/1, these flags are for
consumers, not drivers.

Get rid of a few gpio_to_irq() users that was littering
around the place, use local callbacks or avoid using it at
all.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: mediatek: include chained_irq.h header

Some randconfig builds fail in the mtk-eint driver:

drivers/pinctrl/mediatek/mtk-eint.c: In function 'mtk_eint_irq_handler':
drivers/pinctrl/mediatek/mtk-eint.c:324:2: error: implicit declaration of function 'chained_irq_enter'; did you mean 'rcu_irq_enter'? [-Werror=implicit-function-declaration]
chained_irq_enter(chip, desc);
^~~~~~~~~~~~~~~~~
rcu_irq_enter
drivers/pinctrl/mediatek/mtk-eint.c:367:2: error: implicit declaration of function 'chained_irq_exit'; did you mean 'rcu_irq_exit'? [-Werror=implicit-function-declaration]

The functions are declared in linux/irqchip/chained_irq.h, and including
that header makes it build in all configurations.

Fixes: e46df235b4e6 ("pinctrl: mediatek: refactor EINT related code for all MediaTek pinctrl can fit")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: mediatek: refactor EINT related code for all MediaTek pinctrl can fit

This patch is in preparation for adding EINT support to MT7622 pinctrl,
and the refactoring doesn't alter any existent logic.

A reason we have to refactor EINT code pieces into a generic way is that
currently, they're tightly coupled with a certain type of MediaTek pinctrl
would cause a grown in a very bad way as there is different types of
pinctrl devices getting to join.

Therefore, it is an essential or urgent thing that EINT code pieces are
refactored to eliminate any dependencies across GPIO and EINT as possible.

Additional structure mtk_eint_[xt, hw, regs] are being introduced for
indicating how maps being designed between GPIO and EINT hw number, how to
set and get GPIO state for a certain EINT pin, what characteristic on a
EINT device is present on various SoCs.

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>