linux/drivers/pinctrl/mediatek
Nicolas Boichat 9d957a959b 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: 58a5e1b64b ("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>
2019-06-27 12:22:11 +01:00
..
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile pinctrl: mediatek: Add MT8516 Pinctrl driver 2019-05-03 07:53:13 +01:00
mtk-eint.c pinctrl: mediatek: Update cur_mask in mask/mask ops 2019-06-27 12:22:11 +01:00
mtk-eint.h pinctrl: mediatek: mark dummy helpers as 'static inline' 2018-09-28 09:27:04 +02:00
pinctrl-moore.c pinctrl: mediatek: clean up indentation issues, add missing tab 2018-11-09 09:54:54 +01:00
pinctrl-moore.h pinctrl: mtk: Fix up GPIO includes 2018-09-18 16:38:27 -07:00
pinctrl-mt2701.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
pinctrl-mt2712.c pinctrl: mediatek: remove unused fields in struct mtk_eint_hw 2018-05-24 09:40:10 +02:00
pinctrl-mt6397.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
pinctrl-mt6765.c pinctrl: mediatek: add eint support to MT6765 pinctrl driver 2018-09-21 09:13:54 -07:00
pinctrl-mt6797.c pinctrl: mediatek: Add initial pinctrl driver for MT6797 SoC 2018-11-15 11:05:54 +01:00
pinctrl-mt7622.c pinctrl: mediatek: extend struct mtk_pin_desc which per-pin driver depends on 2018-09-18 14:53:22 -07:00
pinctrl-mt7623.c pinctrl: mediatek: extend struct mtk_pin_desc which per-pin driver depends on 2018-09-18 14:53:22 -07:00
pinctrl-mt7629.c pinctrl: mediatek: add pinctrl support for MT7629 SoC 2018-11-19 15:40:26 +01:00
pinctrl-mt8127.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
pinctrl-mt8135.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
pinctrl-mt8173.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
pinctrl-mt8183.c pinctrl: add drive for I2C related pins on MT8183 2019-04-08 11:20:28 +02:00
pinctrl-mt8516.c pinctrl: mediatek: Add MT8516 Pinctrl driver 2019-05-03 07:53:13 +01:00
pinctrl-mtk-common-v2.c pinctrl: add drive for I2C related pins on MT8183 2019-04-08 11:20:28 +02:00
pinctrl-mtk-common-v2.h pinctrl: add drive for I2C related pins on MT8183 2019-04-08 11:20:28 +02:00
pinctrl-mtk-common.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
pinctrl-mtk-common.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
pinctrl-mtk-mt2701.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
pinctrl-mtk-mt2712.h pinctrl: add mt2712 pinctrl driver 2018-03-26 10:53:39 +02:00
pinctrl-mtk-mt6397.h pinctrl: mtk: fix check warnings. 2018-03-26 10:58:33 +02:00
pinctrl-mtk-mt6765.h pinctrl: mediatek: add MT6765 pinctrl driver 2018-09-21 09:12:55 -07:00
pinctrl-mtk-mt6797.h pinctrl: mediatek: Add initial pinctrl driver for MT6797 SoC 2018-11-15 11:05:54 +01:00
pinctrl-mtk-mt8127.h pinctrl: mtk: fix check warnings. 2018-03-26 10:58:33 +02:00
pinctrl-mtk-mt8135.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
pinctrl-mtk-mt8173.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
pinctrl-mtk-mt8183.h pinctrl: mediatek: add MT8183 pinctrl driver 2018-09-18 14:53:29 -07:00
pinctrl-mtk-mt8516.h pinctrl: mediatek: Add MT8516 Pinctrl driver 2019-05-03 07:53:13 +01:00
pinctrl-paris.c pinctrl: add drive for I2C related pins on MT8183 2019-04-08 11:20:28 +02:00
pinctrl-paris.h pinctrl: mtk: Fix up GPIO includes 2018-09-18 16:38:27 -07:00