Skip to content

Commit

Permalink
platform/x86: x86-android-tablets: Add support for disabling ACPI _AE…
Browse files Browse the repository at this point in the history
…I handlers

Some of the broken DSDTs on these devices often also include broken / wrong
_AEI (ACPI Event Interrupt) handlers, which can cause e.g. interrupt storms
by listening to a floating GPIO pin.

Add support for disabling these and disable them on the Asus ME176C and
TF103C tablets.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-By: Lubomir Rintel <lkundrak@V3.sk>
Link: https://lore.kernel.org/r/20220110103952.48760-1-hdegoede@redhat.com
  • Loading branch information
Hans de Goede committed Jan 24, 2022
1 parent ddec7ab commit 4ce2a32
Showing 1 changed file with 21 additions and 2 deletions.
23 changes: 21 additions & 2 deletions drivers/platform/x86/x86-android-tablets.c
Original file line number Diff line number Diff line change
Expand Up @@ -26,6 +26,7 @@
#include <linux/string.h>
/* For gpio_get_desc() which is EXPORT_SYMBOL_GPL() */
#include "../../gpio/gpiolib.h"
#include "../../gpio/gpiolib-acpi.h"

/*
* Helper code to get Linux IRQ numbers given a description of the IRQ source
Expand All @@ -47,7 +48,7 @@ struct x86_acpi_irq_data {
int polarity; /* ACPI_ACTIVE_HIGH / ACPI_ACTIVE_LOW / ACPI_ACTIVE_BOTH */
};

static int x86_acpi_irq_helper_gpiochip_find(struct gpio_chip *gc, void *data)
static int gpiochip_find_match_label(struct gpio_chip *gc, void *data)
{
return gc->label && !strcmp(gc->label, data);
}
Expand All @@ -73,7 +74,7 @@ static int x86_acpi_irq_helper_get(const struct x86_acpi_irq_data *data)
return irq;
case X86_ACPI_IRQ_TYPE_GPIOINT:
/* Like acpi_dev_gpio_irq_get(), but without parsing ACPI resources */
chip = gpiochip_find(data->chip, x86_acpi_irq_helper_gpiochip_find);
chip = gpiochip_find(data->chip, gpiochip_find_match_label);
if (!chip) {
pr_err("error cannot find GPIO chip %s\n", data->chip);
return -ENODEV;
Expand Down Expand Up @@ -143,6 +144,7 @@ struct x86_serdev_info {
};

struct x86_dev_info {
char *invalid_aei_gpiochip;
const char * const *modules;
struct gpiod_lookup_table **gpiod_lookup_tables;
const struct x86_i2c_client_info *i2c_client_info;
Expand Down Expand Up @@ -317,6 +319,7 @@ static const struct x86_dev_info asus_me176c_info __initconst = {
.serdev_count = ARRAY_SIZE(asus_me176c_serdevs),
.gpiod_lookup_tables = asus_me176c_gpios,
.modules = bq24190_modules,
.invalid_aei_gpiochip = "INT33FC:02",
};

/* Asus TF103C tablets have an Android factory img with everything hardcoded */
Expand Down Expand Up @@ -417,6 +420,7 @@ static const struct x86_dev_info asus_tf103c_info __initconst = {
.pdev_count = ARRAY_SIZE(int3496_pdevs),
.gpiod_lookup_tables = asus_tf103c_gpios,
.modules = bq24190_modules,
.invalid_aei_gpiochip = "INT33FC:02",
};

/*
Expand Down Expand Up @@ -795,6 +799,7 @@ static __init int x86_android_tablet_init(void)
{
const struct x86_dev_info *dev_info;
const struct dmi_system_id *id;
struct gpio_chip *chip;
int i, ret = 0;

id = dmi_first_match(x86_android_tablet_ids);
Expand All @@ -803,6 +808,20 @@ static __init int x86_android_tablet_init(void)

dev_info = id->driver_data;

/*
* The broken DSDTs on these devices often also include broken
* _AEI (ACPI Event Interrupt) handlers, disable these.
*/
if (dev_info->invalid_aei_gpiochip) {
chip = gpiochip_find(dev_info->invalid_aei_gpiochip,
gpiochip_find_match_label);
if (!chip) {
pr_err("error cannot find GPIO chip %s\n", dev_info->invalid_aei_gpiochip);
return -ENODEV;
}
acpi_gpiochip_free_interrupts(chip);
}

/*
* Since this runs from module_init() it cannot use -EPROBE_DEFER,
* instead pre-load any modules which are listed as requirements.
Expand Down

0 comments on commit 4ce2a32

Please sign in to comment.