[PATCH AUTOSEL 5.15 09/31] Input: soc_button_array - add use_low_level_irq module parameter

From: Sasha Levin
Date: Wed Nov 23 2022 - 07:47:57 EST


From: Hans de Goede <hdegoede@xxxxxxxxxx>

[ Upstream commit 8e9ada1d0e72b4737df400fe1bba48dc42a68df7 ]

It seems that the Windows drivers for the ACPI0011 soc_button_array
device use low level triggered IRQs rather then using edge triggering.

Some ACPI tables depend on this, directly poking the GPIO controller's
registers to clear the trigger type when closing a laptop's/2-in-1's lid
and re-instating the trigger when opening the lid again.

Linux sets the edge/level on which to trigger to both low+high since
it is using edge type IRQs, the ACPI tables then ends up also setting
the bit for level IRQs and since both low and high level have been
selected by Linux we get an IRQ storm leading to soft lockups.

As a workaround for this the soc_button_array already contains
a DMI quirk table with device models known to have this issue.

Add a module parameter for this so that users can easily test if their
device is affected too and so that they can use the module parameter
as a workaround.

Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221106215320.67109-1-hdegoede@xxxxxxxxxx
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/input/misc/soc_button_array.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/input/misc/soc_button_array.c b/drivers/input/misc/soc_button_array.c
index efffcf0ebd3b..46ba8218de99 100644
--- a/drivers/input/misc/soc_button_array.c
+++ b/drivers/input/misc/soc_button_array.c
@@ -18,6 +18,10 @@
#include <linux/gpio.h>
#include <linux/platform_device.h>

+static bool use_low_level_irq;
+module_param(use_low_level_irq, bool, 0444);
+MODULE_PARM_DESC(use_low_level_irq, "Use low-level triggered IRQ instead of edge triggered");
+
struct soc_button_info {
const char *name;
int acpi_index;
@@ -164,7 +168,8 @@ soc_button_device_create(struct platform_device *pdev,
}

/* See dmi_use_low_level_irq[] comment */
- if (!autorepeat && dmi_check_system(dmi_use_low_level_irq)) {
+ if (!autorepeat && (use_low_level_irq ||
+ dmi_check_system(dmi_use_low_level_irq))) {
irq_set_irq_type(irq, IRQ_TYPE_LEVEL_LOW);
gpio_keys[n_buttons].irq = irq;
gpio_keys[n_buttons].gpio = -ENOENT;
--
2.35.1