Re: [PATCH 1/3] platform/x86: x86-android-tablets: Add support for disabling ACPI _AEI handlers

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 1/11/22 11:06, Lubomir Rintel wrote:
> On Mon, Jan 10, 2022 at 11:39:50AM +0100, Hans de Goede wrote:
>> 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>
> 
> The whole series looks good to me. Feel free to slap on:
> 
> Reviewed-By: Lubomir Rintel <lkundrak@V3.sk>

Thanks, I've added the tag to the patches in my review-hans branch.

Regards,

Hans



>> ---
>>  drivers/platform/x86/x86-android-tablets.c | 23 ++++++++++++++++++++--
>>  1 file changed, 21 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/platform/x86/x86-android-tablets.c b/drivers/platform/x86/x86-android-tablets.c
>> index 3ba63ad91b28..d125d7a5189a 100644
>> --- a/drivers/platform/x86/x86-android-tablets.c
>> +++ b/drivers/platform/x86/x86-android-tablets.c
>> @@ -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.
>> -- 
>> 2.33.1
>>
>