mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-18 01:34:14 +08:00
1107ca104f
Print error message if requesting an interrupt fails. Use int instead of unsigned for interrupts in case of error values Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
142 lines
3.5 KiB
C
142 lines
3.5 KiB
C
/*
|
|
* ACPI helpers for GPIO API
|
|
*
|
|
* Copyright (C) 2012, Intel Corporation
|
|
* Authors: Mathias Nyman <mathias.nyman@linux.intel.com>
|
|
* Mika Westerberg <mika.westerberg@linux.intel.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/errno.h>
|
|
#include <linux/gpio.h>
|
|
#include <linux/export.h>
|
|
#include <linux/acpi_gpio.h>
|
|
#include <linux/acpi.h>
|
|
#include <linux/interrupt.h>
|
|
|
|
static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
|
|
{
|
|
if (!gc->dev)
|
|
return false;
|
|
|
|
return ACPI_HANDLE(gc->dev) == data;
|
|
}
|
|
|
|
/**
|
|
* acpi_get_gpio() - Translate ACPI GPIO pin to GPIO number usable with GPIO API
|
|
* @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
|
|
* @pin: ACPI GPIO pin number (0-based, controller-relative)
|
|
*
|
|
* Returns GPIO number to use with Linux generic GPIO API, or errno error value
|
|
*/
|
|
|
|
int acpi_get_gpio(char *path, int pin)
|
|
{
|
|
struct gpio_chip *chip;
|
|
acpi_handle handle;
|
|
acpi_status status;
|
|
|
|
status = acpi_get_handle(NULL, path, &handle);
|
|
if (ACPI_FAILURE(status))
|
|
return -ENODEV;
|
|
|
|
chip = gpiochip_find(handle, acpi_gpiochip_find);
|
|
if (!chip)
|
|
return -ENODEV;
|
|
|
|
if (!gpio_is_valid(chip->base + pin))
|
|
return -EINVAL;
|
|
|
|
return chip->base + pin;
|
|
}
|
|
EXPORT_SYMBOL_GPL(acpi_get_gpio);
|
|
|
|
|
|
static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
|
|
{
|
|
acpi_handle handle = data;
|
|
|
|
acpi_evaluate_object(handle, NULL, NULL, NULL);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/**
|
|
* acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
|
|
* @chip: gpio chip
|
|
*
|
|
* ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
|
|
* handled by ACPI event methods which need to be called from the GPIO
|
|
* chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
|
|
* gpio pins have acpi event methods and assigns interrupt handlers that calls
|
|
* the acpi event methods for those pins.
|
|
*
|
|
* Interrupts are automatically freed on driver detach
|
|
*/
|
|
|
|
void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
|
|
{
|
|
struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
|
|
struct acpi_resource *res;
|
|
acpi_handle handle, ev_handle;
|
|
acpi_status status;
|
|
unsigned int pin;
|
|
int irq, ret;
|
|
char ev_name[5];
|
|
|
|
if (!chip->dev || !chip->to_irq)
|
|
return;
|
|
|
|
handle = ACPI_HANDLE(chip->dev);
|
|
if (!handle)
|
|
return;
|
|
|
|
status = acpi_get_event_resources(handle, &buf);
|
|
if (ACPI_FAILURE(status))
|
|
return;
|
|
|
|
/* If a gpio interrupt has an acpi event handler method, then
|
|
* set up an interrupt handler that calls the acpi event handler
|
|
*/
|
|
|
|
for (res = buf.pointer;
|
|
res && (res->type != ACPI_RESOURCE_TYPE_END_TAG);
|
|
res = ACPI_NEXT_RESOURCE(res)) {
|
|
|
|
if (res->type != ACPI_RESOURCE_TYPE_GPIO ||
|
|
res->data.gpio.connection_type !=
|
|
ACPI_RESOURCE_GPIO_TYPE_INT)
|
|
continue;
|
|
|
|
pin = res->data.gpio.pin_table[0];
|
|
if (pin > chip->ngpio)
|
|
continue;
|
|
|
|
sprintf(ev_name, "_%c%02X",
|
|
res->data.gpio.triggering ? 'E' : 'L', pin);
|
|
|
|
status = acpi_get_handle(handle, ev_name, &ev_handle);
|
|
if (ACPI_FAILURE(status))
|
|
continue;
|
|
|
|
irq = chip->to_irq(chip, pin);
|
|
if (irq < 0)
|
|
continue;
|
|
|
|
/* Assume BIOS sets the triggering, so no flags */
|
|
ret = devm_request_threaded_irq(chip->dev, irq, NULL,
|
|
acpi_gpio_irq_handler,
|
|
0,
|
|
"GPIO-signaled-ACPI-event",
|
|
ev_handle);
|
|
if (ret)
|
|
dev_err(chip->dev,
|
|
"Failed to request IRQ %d ACPI event handler\n",
|
|
irq);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(acpi_gpiochip_request_interrupts);
|