Commit 4ce2a32d authored by Hans de Goede's avatar Hans de Goede
Browse files

platform/x86: x86-android-tablets: Add support for disabling ACPI _AEI 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: default avatarHans de Goede <hdegoede@redhat.com>
Reviewed-By: default avatarLubomir Rintel <lkundrak@V3.sk>
Link: https://lore.kernel.org/r/20220110103952.48760-1-hdegoede@redhat.com
parent ddec7abd

drivers/platform/x86/x86-android-tablets.c

+21 −2
Original line number Diff line number Diff line
@@ -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
@@ -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);

}
@@ -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;
@@ -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;
@@ -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 */
@@ -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",

};



/*
@@ -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);
@@ -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.