[deliverable/linux.git] / drivers / gpio / gpiolib-acpi.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/consumer.h>
#include <linux/gpio/driver.h>
#include <linux/export.h>
#include <linux/acpi.h>
#include <linux/interrupt.h>
#include <linux/mutex.h>

#include "gpiolib.h"

struct acpi_gpio_event {
	struct list_head node;
	acpi_handle handle;
	unsigned int pin;
	unsigned int irq;
	struct gpio_desc *desc;
};

struct acpi_gpio_connection {
	struct list_head node;
	unsigned int pin;
	struct gpio_desc *desc;
};

struct acpi_gpio_chip {
	/*
	 * ACPICA requires that the first field of the context parameter
	 * passed to acpi_install_address_space_handler() is large enough
	 * to hold struct acpi_connection_info.
	 */
	struct acpi_connection_info conn_info;
	struct list_head conns;
	struct mutex conn_lock;
	struct gpio_chip *chip;
	struct list_head events;
};

static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
{
	if (!gc->dev)
		return false;

	return ACPI_HANDLE(gc->dev) == data;
}

/**
 * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor 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 descriptor to use with Linux generic GPIO API, or ERR_PTR
 * error value
 */

static struct gpio_desc *acpi_get_gpiod(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 ERR_PTR(-ENODEV);

	chip = gpiochip_find(handle, acpi_gpiochip_find);
	if (!chip)
		return ERR_PTR(-ENODEV);

	if (pin < 0 || pin > chip->ngpio)
		return ERR_PTR(-EINVAL);

	return gpiochip_get_desc(chip, pin);
}

static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
{
	struct acpi_gpio_event *event = data;

	acpi_evaluate_object(event->handle, NULL, NULL, NULL);

	return IRQ_HANDLED;
}

static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
{
	struct acpi_gpio_event *event = data;

	acpi_execute_simple_method(event->handle, NULL, event->pin);

	return IRQ_HANDLED;
}

static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
{
	/* The address of this function is used as a key. */
}

static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares,
						   void *context)
{
	struct acpi_gpio_chip *acpi_gpio = context;
	struct gpio_chip *chip = acpi_gpio->chip;
	struct acpi_resource_gpio *agpio;
	acpi_handle handle, evt_handle;
	struct acpi_gpio_event *event;
	irq_handler_t handler = NULL;
	struct gpio_desc *desc;
	unsigned long irqflags;
	int ret, pin, irq;

	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
		return AE_OK;

	agpio = &ares->data.gpio;
	if (agpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
		return AE_OK;

	handle = ACPI_HANDLE(chip->dev);
	pin = agpio->pin_table[0];

	if (pin <= 255) {
		char ev_name[5];
		sprintf(ev_name, "_%c%02X",
			agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
			pin);
		if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
			handler = acpi_gpio_irq_handler;
	}
	if (!handler) {
		if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
			handler = acpi_gpio_irq_handler_evt;
	}
	if (!handler)
		return AE_BAD_PARAMETER;

	desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event");
	if (IS_ERR(desc)) {
		dev_err(chip->dev, "Failed to request GPIO\n");
		return AE_ERROR;
	}

	gpiod_direction_input(desc);

	ret = gpio_lock_as_irq(chip, pin);
	if (ret) {
		dev_err(chip->dev, "Failed to lock GPIO as interrupt\n");
		goto fail_free_desc;
	}

	irq = gpiod_to_irq(desc);
	if (irq < 0) {
		dev_err(chip->dev, "Failed to translate GPIO to IRQ\n");
		goto fail_unlock_irq;
	}

	irqflags = IRQF_ONESHOT;
	if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
		if (agpio->polarity == ACPI_ACTIVE_HIGH)
			irqflags |= IRQF_TRIGGER_HIGH;
		else
			irqflags |= IRQF_TRIGGER_LOW;
	} else {
		switch (agpio->polarity) {
		case ACPI_ACTIVE_HIGH:
			irqflags |= IRQF_TRIGGER_RISING;
			break;
		case ACPI_ACTIVE_LOW:
			irqflags |= IRQF_TRIGGER_FALLING;
			break;
		default:
			irqflags |= IRQF_TRIGGER_RISING |
				    IRQF_TRIGGER_FALLING;
			break;
		}
	}

	event = kzalloc(sizeof(*event), GFP_KERNEL);
	if (!event)
		goto fail_unlock_irq;

	event->handle = evt_handle;
	event->irq = irq;
	event->pin = pin;
	event->desc = desc;

	ret = request_threaded_irq(event->irq, NULL, handler, irqflags,
				   "ACPI:Event", event);
	if (ret) {
		dev_err(chip->dev, "Failed to setup interrupt handler for %d\n",
			event->irq);
		goto fail_free_event;
	}

	list_add_tail(&event->node, &acpi_gpio->events);
	return AE_OK;

fail_free_event:
	kfree(event);
fail_unlock_irq:
	gpio_unlock_as_irq(chip, pin);
fail_free_desc:
	gpiochip_free_own_desc(desc);

	return AE_ERROR;
}

/**
 * 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.
 */
void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
{
	struct acpi_gpio_chip *acpi_gpio;
	acpi_handle handle;
	acpi_status status;

	if (!chip->dev || !chip->to_irq)
		return;

	handle = ACPI_HANDLE(chip->dev);
	if (!handle)
		return;

	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
	if (ACPI_FAILURE(status))
		return;

	INIT_LIST_HEAD(&acpi_gpio->events);
	acpi_walk_resources(ACPI_HANDLE(chip->dev), "_AEI",
			    acpi_gpiochip_request_interrupt, acpi_gpio);
}

/**
 * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
 * @chip:      GPIO chip
 *
 * Free interrupts associated with GPIO ACPI event method for the given
 * GPIO chip.
 */
void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
{
	struct acpi_gpio_chip *acpi_gpio;
	struct acpi_gpio_event *event, *ep;
	acpi_handle handle;
	acpi_status status;

	if (!chip->dev || !chip->to_irq)
		return;

	handle = ACPI_HANDLE(chip->dev);
	if (!handle)
		return;

	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
	if (ACPI_FAILURE(status))
		return;

	list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
		struct gpio_desc *desc;

		free_irq(event->irq, event);
		desc = event->desc;
		if (WARN_ON(IS_ERR(desc)))
			continue;
		gpio_unlock_as_irq(chip, event->pin);
		gpiochip_free_own_desc(desc);
		list_del(&event->node);
		kfree(event);
	}
}

struct acpi_gpio_lookup {
	struct acpi_gpio_info info;
	int index;
	struct gpio_desc *desc;
	int n;
};

static int acpi_find_gpio(struct acpi_resource *ares, void *data)
{
	struct acpi_gpio_lookup *lookup = data;

	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
		return 1;

	if (lookup->n++ == lookup->index && !lookup->desc) {
		const struct acpi_resource_gpio *agpio = &ares->data.gpio;

		lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
					      agpio->pin_table[0]);
		lookup->info.gpioint =
			agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
		lookup->info.active_low =
			agpio->polarity == ACPI_ACTIVE_LOW;
	}

	return 1;
}

/**
 * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
 * @dev: pointer to a device to get GPIO from
 * @index: index of GpioIo/GpioInt resource (starting from %0)
 * @info: info pointer to fill in (optional)
 *
 * Function goes through ACPI resources for @dev and based on @index looks
 * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
 * and returns it. @index matches GpioIo/GpioInt resources only so if there
 * are total %3 GPIO resources, the index goes from %0 to %2.
 *
 * If the GPIO cannot be translated or there is an error an ERR_PTR is
 * returned.
 *
 * Note: if the GPIO resource has multiple entries in the pin list, this
 * function only returns the first.
 */
struct gpio_desc *acpi_get_gpiod_by_index(struct device *dev, int index,
					  struct acpi_gpio_info *info)
{
	struct acpi_gpio_lookup lookup;
	struct list_head resource_list;
	struct acpi_device *adev;
	acpi_handle handle;
	int ret;

	if (!dev)
		return ERR_PTR(-EINVAL);

	handle = ACPI_HANDLE(dev);
	if (!handle || acpi_bus_get_device(handle, &adev))
		return ERR_PTR(-ENODEV);

	memset(&lookup, 0, sizeof(lookup));
	lookup.index = index;

	INIT_LIST_HEAD(&resource_list);
	ret = acpi_dev_get_resources(adev, &resource_list, acpi_find_gpio,
				     &lookup);
	if (ret < 0)
		return ERR_PTR(ret);

	acpi_dev_free_resource_list(&resource_list);

	if (lookup.desc && info)
		*info = lookup.info;

	return lookup.desc ? lookup.desc : ERR_PTR(-ENOENT);
}

static acpi_status
acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
			    u32 bits, u64 *value, void *handler_context,
			    void *region_context)
{
	struct acpi_gpio_chip *achip = region_context;
	struct gpio_chip *chip = achip->chip;
	struct acpi_resource_gpio *agpio;
	struct acpi_resource *ares;
	int pin_index = (int)address;
	acpi_status status;
	bool pull_up;
	int length;
	int i;

	status = acpi_buffer_to_resource(achip->conn_info.connection,
					 achip->conn_info.length, &ares);
	if (ACPI_FAILURE(status))
		return status;

	if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
		ACPI_FREE(ares);
		return AE_BAD_PARAMETER;
	}

	agpio = &ares->data.gpio;
	pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;

	if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
	    function == ACPI_WRITE)) {
		ACPI_FREE(ares);
		return AE_BAD_PARAMETER;
	}

	length = min(agpio->pin_table_length, (u16)(pin_index + bits));
	for (i = pin_index; i < length; ++i) {
		unsigned pin = agpio->pin_table[i];
		struct acpi_gpio_connection *conn;
		struct gpio_desc *desc;
		bool found;

		mutex_lock(&achip->conn_lock);

		found = false;
		list_for_each_entry(conn, &achip->conns, node) {
			if (conn->pin == pin) {
				found = true;
				desc = conn->desc;
				break;
			}
		}
		if (!found) {
			desc = gpiochip_request_own_desc(chip, pin,
							 "ACPI:OpRegion");
			if (IS_ERR(desc)) {
				status = AE_ERROR;
				mutex_unlock(&achip->conn_lock);
				goto out;
			}

			switch (agpio->io_restriction) {
			case ACPI_IO_RESTRICT_INPUT:
				gpiod_direction_input(desc);
				break;
			case ACPI_IO_RESTRICT_OUTPUT:
				/*
				 * ACPI GPIO resources don't contain an
				 * initial value for the GPIO. Therefore we
				 * deduce that value from the pull field
				 * instead. If the pin is pulled up we
				 * assume default to be high, otherwise
				 * low.
				 */
				gpiod_direction_output(desc, pull_up);
				break;
			default:
				/*
				 * Assume that the BIOS has configured the
				 * direction and pull accordingly.
				 */
				break;
			}

			conn = kzalloc(sizeof(*conn), GFP_KERNEL);
			if (!conn) {
				status = AE_NO_MEMORY;
				gpiochip_free_own_desc(desc);
				mutex_unlock(&achip->conn_lock);
				goto out;
			}

			conn->pin = pin;
			conn->desc = desc;
			list_add_tail(&conn->node, &achip->conns);
		}

		mutex_unlock(&achip->conn_lock);

		if (function == ACPI_WRITE)
			gpiod_set_raw_value_cansleep(desc,
						     !!((1 << i) & *value));
		else
			*value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
	}

out:
	ACPI_FREE(ares);
	return status;
}

static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
{
	struct gpio_chip *chip = achip->chip;
	acpi_handle handle = ACPI_HANDLE(chip->dev);
	acpi_status status;

	INIT_LIST_HEAD(&achip->conns);
	mutex_init(&achip->conn_lock);
	status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
						    acpi_gpio_adr_space_handler,
						    NULL, achip);
	if (ACPI_FAILURE(status))
		dev_err(chip->dev, "Failed to install GPIO OpRegion handler\n");
}

static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
{
	struct gpio_chip *chip = achip->chip;
	acpi_handle handle = ACPI_HANDLE(chip->dev);
	struct acpi_gpio_connection *conn, *tmp;
	acpi_status status;

	status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
						   acpi_gpio_adr_space_handler);
	if (ACPI_FAILURE(status)) {
		dev_err(chip->dev, "Failed to remove GPIO OpRegion handler\n");
		return;
	}

	list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
		gpiochip_free_own_desc(conn->desc);
		list_del(&conn->node);
		kfree(conn);
	}
}

void acpi_gpiochip_add(struct gpio_chip *chip)
{
	struct acpi_gpio_chip *acpi_gpio;
	acpi_handle handle;
	acpi_status status;

	if (!chip || !chip->dev)
		return;

	handle = ACPI_HANDLE(chip->dev);
	if (!handle)
		return;

	acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
	if (!acpi_gpio) {
		dev_err(chip->dev,
			"Failed to allocate memory for ACPI GPIO chip\n");
		return;
	}

	acpi_gpio->chip = chip;

	status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
	if (ACPI_FAILURE(status)) {
		dev_err(chip->dev, "Failed to attach ACPI GPIO chip\n");
		kfree(acpi_gpio);
		return;
	}

	acpi_gpiochip_request_regions(acpi_gpio);
}

void acpi_gpiochip_remove(struct gpio_chip *chip)
{
	struct acpi_gpio_chip *acpi_gpio;
	acpi_handle handle;
	acpi_status status;

	if (!chip || !chip->dev)
		return;

	handle = ACPI_HANDLE(chip->dev);
	if (!handle)
		return;

	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
	if (ACPI_FAILURE(status)) {
		dev_warn(chip->dev, "Failed to retrieve ACPI GPIO chip\n");
		return;
	}

	acpi_gpiochip_free_regions(acpi_gpio);

	acpi_detach_data(handle, acpi_gpio_chip_dh);
	kfree(acpi_gpio);
}
Commit	Line	Data
e29482e8 MN	1	/*
	2	* ACPI helpers for GPIO API
	3	*
	4	* Copyright (C) 2012, Intel Corporation
	5	* Authors: Mathias Nyman <mathias.nyman@linux.intel.com>
	6	* Mika Westerberg <mika.westerberg@linux.intel.com>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11	*/
	12
	13	#include <linux/errno.h>
936e15dd	14	#include <linux/gpio/consumer.h>
5ccff852	15	#include <linux/gpio/driver.h>
e29482e8	16	#include <linux/export.h>
e29482e8	17	#include <linux/acpi.h>
0d1c28a4	18	#include <linux/interrupt.h>
473ed7be	19	#include <linux/mutex.h>
e29482e8	20
5ccff852 MW	21	#include "gpiolib.h"
5ccff852 MW	22
4b01a14b	23	struct acpi_gpio_event {
7fc7acb9	24	struct list_head node;
4b01a14b	25	acpi_handle handle;
7fc7acb9 RW	26	unsigned int pin;
7fc7acb9 RW	27	unsigned int irq;
e46cf32c	28	struct gpio_desc *desc;
7fc7acb9 RW	29	};
7fc7acb9 RW	30
473ed7be MW	31	struct acpi_gpio_connection {
473ed7be MW	32	struct list_head node;
e46cf32c	33	unsigned int pin;
473ed7be MW	34	struct gpio_desc *desc;
	35	};
	36
aa92b6f6	37	struct acpi_gpio_chip {
473ed7be MW	38	/*
	39	* ACPICA requires that the first field of the context parameter
	40	* passed to acpi_install_address_space_handler() is large enough
	41	* to hold struct acpi_connection_info.
	42	*/
	43	struct acpi_connection_info conn_info;
	44	struct list_head conns;
	45	struct mutex conn_lock;
aa92b6f6	46	struct gpio_chip *chip;
4b01a14b	47	struct list_head events;
aa92b6f6 MW	48	};
aa92b6f6 MW	49
e29482e8 MN	50	static int acpi_gpiochip_find(struct gpio_chip gc, void data)
	51	{
	52	if (!gc->dev)
	53	return false;
	54
	55	return ACPI_HANDLE(gc->dev) == data;
	56	}
	57
	58	/**
936e15dd	59	* acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
e29482e8 MN	60	* @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
	61	* @pin: ACPI GPIO pin number (0-based, controller-relative)
	62	*
936e15dd MW	63	* Returns GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
936e15dd MW	64	* error value
e29482e8 MN	65	*/
e29482e8 MN	66
936e15dd	67	static struct gpio_desc acpi_get_gpiod(char path, int pin)
e29482e8 MN	68	{
	69	struct gpio_chip *chip;
	70	acpi_handle handle;
	71	acpi_status status;
	72
	73	status = acpi_get_handle(NULL, path, &handle);
	74	if (ACPI_FAILURE(status))
936e15dd	75	return ERR_PTR(-ENODEV);
e29482e8 MN	76
	77	chip = gpiochip_find(handle, acpi_gpiochip_find);
	78	if (!chip)
936e15dd	79	return ERR_PTR(-ENODEV);
e29482e8	80
936e15dd MW	81	if (pin < 0 \|\| pin > chip->ngpio)
936e15dd MW	82	return ERR_PTR(-EINVAL);
e29482e8	83
390d82e3	84	return gpiochip_get_desc(chip, pin);
e29482e8	85	}
0d1c28a4	86
0d1c28a4 MN	87	static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
0d1c28a4 MN	88	{
6072b9dc	89	struct acpi_gpio_event *event = data;
0d1c28a4	90
6072b9dc	91	acpi_evaluate_object(event->handle, NULL, NULL, NULL);
0d1c28a4 MN	92
	93	return IRQ_HANDLED;
	94	}
	95
7fc7acb9 RW	96	static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
7fc7acb9 RW	97	{
4b01a14b	98	struct acpi_gpio_event *event = data;
7fc7acb9	99
4b01a14b	100	acpi_execute_simple_method(event->handle, NULL, event->pin);
7fc7acb9 RW	101
	102	return IRQ_HANDLED;
	103	}
	104
aa92b6f6	105	static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
7fc7acb9 RW	106	{
	107	/* The address of this function is used as a key. */
	108	}
	109
6072b9dc MW	110	static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares,
6072b9dc MW	111	void *context)
0d1c28a4	112	{
6072b9dc	113	struct acpi_gpio_chip *acpi_gpio = context;
aa92b6f6	114	struct gpio_chip *chip = acpi_gpio->chip;
6072b9dc	115	struct acpi_resource_gpio *agpio;
7fc7acb9	116	acpi_handle handle, evt_handle;
6072b9dc MW	117	struct acpi_gpio_event *event;
	118	irq_handler_t handler = NULL;
	119	struct gpio_desc *desc;
	120	unsigned long irqflags;
	121	int ret, pin, irq;
0d1c28a4	122
6072b9dc MW	123	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
	124	return AE_OK;
	125
	126	agpio = &ares->data.gpio;
	127	if (agpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
	128	return AE_OK;
0d1c28a4 MN	129
0d1c28a4 MN	130	handle = ACPI_HANDLE(chip->dev);
6072b9dc MW	131	pin = agpio->pin_table[0];
	132
	133	if (pin <= 255) {
	134	char ev_name[5];
	135	sprintf(ev_name, "_%c%02X",
	136	agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
	137	pin);
	138	if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
	139	handler = acpi_gpio_irq_handler;
	140	}
	141	if (!handler) {
	142	if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
	143	handler = acpi_gpio_irq_handler_evt;
	144	}
	145	if (!handler)
	146	return AE_BAD_PARAMETER;
0d1c28a4	147
abdc08a3	148	desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event");
6072b9dc	149	if (IS_ERR(desc)) {
6072b9dc MW	150	dev_err(chip->dev, "Failed to request GPIO\n");
	151	return AE_ERROR;
	152	}
0d1c28a4	153
6072b9dc	154	gpiod_direction_input(desc);
0d1c28a4	155
d74be6df	156	ret = gpio_lock_as_irq(chip, pin);
6072b9dc MW	157	if (ret) {
	158	dev_err(chip->dev, "Failed to lock GPIO as interrupt\n");
	159	goto fail_free_desc;
	160	}
0d1c28a4	161
6072b9dc MW	162	irq = gpiod_to_irq(desc);
	163	if (irq < 0) {
	164	dev_err(chip->dev, "Failed to translate GPIO to IRQ\n");
	165	goto fail_unlock_irq;
	166	}
7fc7acb9	167
6072b9dc MW	168	irqflags = IRQF_ONESHOT;
	169	if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
	170	if (agpio->polarity == ACPI_ACTIVE_HIGH)
	171	irqflags \|= IRQF_TRIGGER_HIGH;
	172	else
	173	irqflags \|= IRQF_TRIGGER_LOW;
	174	} else {
	175	switch (agpio->polarity) {
	176	case ACPI_ACTIVE_HIGH:
	177	irqflags \|= IRQF_TRIGGER_RISING;
	178	break;
	179	case ACPI_ACTIVE_LOW:
	180	irqflags \|= IRQF_TRIGGER_FALLING;
	181	break;
	182	default:
	183	irqflags \|= IRQF_TRIGGER_RISING \|
	184	IRQF_TRIGGER_FALLING;
	185	break;
7fc7acb9	186	}
6072b9dc	187	}
aa92b6f6	188
6072b9dc MW	189	event = kzalloc(sizeof(*event), GFP_KERNEL);
	190	if (!event)
	191	goto fail_unlock_irq;
7fc7acb9	192
6072b9dc MW	193	event->handle = evt_handle;
	194	event->irq = irq;
	195	event->pin = pin;
e46cf32c	196	event->desc = desc;
7fc7acb9	197
6072b9dc MW	198	ret = request_threaded_irq(event->irq, NULL, handler, irqflags,
	199	"ACPI:Event", event);
	200	if (ret) {
	201	dev_err(chip->dev, "Failed to setup interrupt handler for %d\n",
	202	event->irq);
	203	goto fail_free_event;
0d1c28a4	204	}
6072b9dc MW	205
	206	list_add_tail(&event->node, &acpi_gpio->events);
	207	return AE_OK;
	208
	209	fail_free_event:
	210	kfree(event);
	211	fail_unlock_irq:
d74be6df	212	gpio_unlock_as_irq(chip, pin);
6072b9dc MW	213	fail_free_desc:
	214	gpiochip_free_own_desc(desc);
	215
	216	return AE_ERROR;
0d1c28a4	217	}
7fc7acb9	218
70b53411	219	/**
6072b9dc	220	* acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
afa82fab	221	* @chip: GPIO chip
70b53411	222	*
6072b9dc MW	223	* ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
	224	* handled by ACPI event methods which need to be called from the GPIO
	225	* chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
	226	* gpio pins have acpi event methods and assigns interrupt handlers that calls
	227	* the acpi event methods for those pins.
	228	*/
afa82fab	229	void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
6072b9dc	230	{
afa82fab MW	231	struct acpi_gpio_chip *acpi_gpio;
	232	acpi_handle handle;
	233	acpi_status status;
	234
	235	if (!chip->dev \|\| !chip->to_irq)
	236	return;
6072b9dc	237
afa82fab MW	238	handle = ACPI_HANDLE(chip->dev);
	239	if (!handle)
	240	return;
	241
	242	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
	243	if (ACPI_FAILURE(status))
6072b9dc MW	244	return;
	245
	246	INIT_LIST_HEAD(&acpi_gpio->events);
	247	acpi_walk_resources(ACPI_HANDLE(chip->dev), "_AEI",
	248	acpi_gpiochip_request_interrupt, acpi_gpio);
	249	}
	250
	251	/**
	252	* acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
afa82fab	253	* @chip: GPIO chip
70b53411	254	*
6072b9dc MW	255	* Free interrupts associated with GPIO ACPI event method for the given
6072b9dc MW	256	* GPIO chip.
70b53411	257	*/
afa82fab	258	void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
70b53411	259	{
afa82fab	260	struct acpi_gpio_chip *acpi_gpio;
4b01a14b	261	struct acpi_gpio_event event, ep;
afa82fab MW	262	acpi_handle handle;
	263	acpi_status status;
	264
	265	if (!chip->dev \|\| !chip->to_irq)
	266	return;
70b53411	267
afa82fab MW	268	handle = ACPI_HANDLE(chip->dev);
	269	if (!handle)
	270	return;
	271
	272	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
	273	if (ACPI_FAILURE(status))
70b53411 MW	274	return;
70b53411 MW	275
4b01a14b	276	list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
6072b9dc MW	277	struct gpio_desc *desc;
	278
	279	free_irq(event->irq, event);
e46cf32c	280	desc = event->desc;
6072b9dc MW	281	if (WARN_ON(IS_ERR(desc)))
6072b9dc MW	282	continue;
d74be6df	283	gpio_unlock_as_irq(chip, event->pin);
6072b9dc	284	gpiochip_free_own_desc(desc);
4b01a14b MW	285	list_del(&event->node);
4b01a14b MW	286	kfree(event);
70b53411	287	}
70b53411	288	}
70b53411	289
12028d2d MW	290	struct acpi_gpio_lookup {
	291	struct acpi_gpio_info info;
	292	int index;
936e15dd	293	struct gpio_desc *desc;
12028d2d MW	294	int n;
	295	};
	296
	297	static int acpi_find_gpio(struct acpi_resource ares, void data)
	298	{
	299	struct acpi_gpio_lookup *lookup = data;
	300
	301	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
	302	return 1;
	303
936e15dd	304	if (lookup->n++ == lookup->index && !lookup->desc) {
12028d2d MW	305	const struct acpi_resource_gpio *agpio = &ares->data.gpio;
12028d2d MW	306
936e15dd MW	307	lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
936e15dd MW	308	agpio->pin_table[0]);
12028d2d MW	309	lookup->info.gpioint =
12028d2d MW	310	agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
e01f440a MW	311	lookup->info.active_low =
e01f440a MW	312	agpio->polarity == ACPI_ACTIVE_LOW;
12028d2d MW	313	}
	314
	315	return 1;
	316	}
	317
	318	/**
936e15dd	319	* acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
12028d2d MW	320	* @dev: pointer to a device to get GPIO from
	321	* @index: index of GpioIo/GpioInt resource (starting from %0)
	322	* @info: info pointer to fill in (optional)
	323	*
	324	* Function goes through ACPI resources for @dev and based on @index looks
936e15dd	325	* up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
12028d2d MW	326	* and returns it. @index matches GpioIo/GpioInt resources only so if there
	327	* are total %3 GPIO resources, the index goes from %0 to %2.
	328	*
936e15dd	329	* If the GPIO cannot be translated or there is an error an ERR_PTR is
12028d2d MW	330	* returned.
	331	*
	332	* Note: if the GPIO resource has multiple entries in the pin list, this
	333	* function only returns the first.
	334	*/
936e15dd MW	335	struct gpio_desc acpi_get_gpiod_by_index(struct device dev, int index,
936e15dd MW	336	struct acpi_gpio_info *info)
12028d2d MW	337	{
	338	struct acpi_gpio_lookup lookup;
	339	struct list_head resource_list;
	340	struct acpi_device *adev;
	341	acpi_handle handle;
	342	int ret;
	343
	344	if (!dev)
936e15dd	345	return ERR_PTR(-EINVAL);
12028d2d MW	346
	347	handle = ACPI_HANDLE(dev);
	348	if (!handle \|\| acpi_bus_get_device(handle, &adev))
936e15dd	349	return ERR_PTR(-ENODEV);
12028d2d MW	350
	351	memset(&lookup, 0, sizeof(lookup));
	352	lookup.index = index;
12028d2d MW	353
	354	INIT_LIST_HEAD(&resource_list);
	355	ret = acpi_dev_get_resources(adev, &resource_list, acpi_find_gpio,
	356	&lookup);
	357	if (ret < 0)
936e15dd	358	return ERR_PTR(ret);
12028d2d MW	359
	360	acpi_dev_free_resource_list(&resource_list);
	361
936e15dd	362	if (lookup.desc && info)
12028d2d MW	363	*info = lookup.info;
12028d2d MW	364
a00580c2	365	return lookup.desc ? lookup.desc : ERR_PTR(-ENOENT);
12028d2d	366	}
664e3e5a	367
473ed7be MW	368	static acpi_status
	369	acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
	370	u32 bits, u64 value, void handler_context,
	371	void *region_context)
	372	{
	373	struct acpi_gpio_chip *achip = region_context;
	374	struct gpio_chip *chip = achip->chip;
	375	struct acpi_resource_gpio *agpio;
	376	struct acpi_resource *ares;
c15d821d	377	int pin_index = (int)address;
473ed7be MW	378	acpi_status status;
473ed7be MW	379	bool pull_up;
c15d821d	380	int length;
473ed7be MW	381	int i;
	382
	383	status = acpi_buffer_to_resource(achip->conn_info.connection,
	384	achip->conn_info.length, &ares);
	385	if (ACPI_FAILURE(status))
	386	return status;
	387
	388	if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
	389	ACPI_FREE(ares);
	390	return AE_BAD_PARAMETER;
	391	}
	392
	393	agpio = &ares->data.gpio;
	394	pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
	395
	396	if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
	397	function == ACPI_WRITE)) {
	398	ACPI_FREE(ares);
	399	return AE_BAD_PARAMETER;
	400	}
	401
c15d821d SP	402	length = min(agpio->pin_table_length, (u16)(pin_index + bits));
c15d821d SP	403	for (i = pin_index; i < length; ++i) {
473ed7be MW	404	unsigned pin = agpio->pin_table[i];
	405	struct acpi_gpio_connection *conn;
	406	struct gpio_desc *desc;
	407	bool found;
	408
473ed7be MW	409	mutex_lock(&achip->conn_lock);
	410
	411	found = false;
	412	list_for_each_entry(conn, &achip->conns, node) {
e46cf32c	413	if (conn->pin == pin) {
473ed7be	414	found = true;
e46cf32c	415	desc = conn->desc;
473ed7be MW	416	break;
	417	}
	418	}
	419	if (!found) {
abdc08a3 AC	420	desc = gpiochip_request_own_desc(chip, pin,
abdc08a3 AC	421	"ACPI:OpRegion");
e46cf32c	422	if (IS_ERR(desc)) {
473ed7be MW	423	status = AE_ERROR;
	424	mutex_unlock(&achip->conn_lock);
	425	goto out;
	426	}
	427
	428	switch (agpio->io_restriction) {
	429	case ACPI_IO_RESTRICT_INPUT:
	430	gpiod_direction_input(desc);
	431	break;
	432	case ACPI_IO_RESTRICT_OUTPUT:
	433	/*
	434	* ACPI GPIO resources don't contain an
	435	* initial value for the GPIO. Therefore we
	436	* deduce that value from the pull field
	437	* instead. If the pin is pulled up we
	438	* assume default to be high, otherwise
	439	* low.
	440	*/
	441	gpiod_direction_output(desc, pull_up);
	442	break;
	443	default:
	444	/*
	445	* Assume that the BIOS has configured the
	446	* direction and pull accordingly.
	447	*/
	448	break;
	449	}
	450
	451	conn = kzalloc(sizeof(*conn), GFP_KERNEL);
	452	if (!conn) {
	453	status = AE_NO_MEMORY;
	454	gpiochip_free_own_desc(desc);
	455	mutex_unlock(&achip->conn_lock);
	456	goto out;
	457	}
	458
e46cf32c	459	conn->pin = pin;
473ed7be MW	460	conn->desc = desc;
	461	list_add_tail(&conn->node, &achip->conns);
	462	}
	463
	464	mutex_unlock(&achip->conn_lock);
	465
	466	if (function == ACPI_WRITE)
dc62b56a AL	467	gpiod_set_raw_value_cansleep(desc,
dc62b56a AL	468	!!((1 << i) & *value));
473ed7be	469	else
dc62b56a	470	*value \|= (u64)gpiod_get_raw_value_cansleep(desc) << i;
473ed7be MW	471	}
	472
	473	out:
	474	ACPI_FREE(ares);
	475	return status;
	476	}
	477
	478	static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
	479	{
	480	struct gpio_chip *chip = achip->chip;
	481	acpi_handle handle = ACPI_HANDLE(chip->dev);
	482	acpi_status status;
	483
	484	INIT_LIST_HEAD(&achip->conns);
	485	mutex_init(&achip->conn_lock);
	486	status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
	487	acpi_gpio_adr_space_handler,
	488	NULL, achip);
	489	if (ACPI_FAILURE(status))
	490	dev_err(chip->dev, "Failed to install GPIO OpRegion handler\n");
	491	}
	492
	493	static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
	494	{
	495	struct gpio_chip *chip = achip->chip;
	496	acpi_handle handle = ACPI_HANDLE(chip->dev);
	497	struct acpi_gpio_connection conn, tmp;
	498	acpi_status status;
	499
	500	status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
	501	acpi_gpio_adr_space_handler);
	502	if (ACPI_FAILURE(status)) {
	503	dev_err(chip->dev, "Failed to remove GPIO OpRegion handler\n");
	504	return;
	505	}
	506
	507	list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
	508	gpiochip_free_own_desc(conn->desc);
	509	list_del(&conn->node);
	510	kfree(conn);
	511	}
	512	}
	513
664e3e5a MW	514	void acpi_gpiochip_add(struct gpio_chip *chip)
664e3e5a MW	515	{
aa92b6f6 MW	516	struct acpi_gpio_chip *acpi_gpio;
	517	acpi_handle handle;
	518	acpi_status status;
	519
e9595f84 MW	520	if (!chip \|\| !chip->dev)
	521	return;
	522
aa92b6f6 MW	523	handle = ACPI_HANDLE(chip->dev);
	524	if (!handle)
	525	return;
	526
	527	acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
	528	if (!acpi_gpio) {
	529	dev_err(chip->dev,
	530	"Failed to allocate memory for ACPI GPIO chip\n");
	531	return;
	532	}
	533
	534	acpi_gpio->chip = chip;
	535
	536	status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
	537	if (ACPI_FAILURE(status)) {
	538	dev_err(chip->dev, "Failed to attach ACPI GPIO chip\n");
	539	kfree(acpi_gpio);
	540	return;
	541	}
	542
473ed7be	543	acpi_gpiochip_request_regions(acpi_gpio);
664e3e5a MW	544	}
	545
	546	void acpi_gpiochip_remove(struct gpio_chip *chip)
	547	{
aa92b6f6 MW	548	struct acpi_gpio_chip *acpi_gpio;
	549	acpi_handle handle;
	550	acpi_status status;
	551
e9595f84 MW	552	if (!chip \|\| !chip->dev)
	553	return;
	554
aa92b6f6 MW	555	handle = ACPI_HANDLE(chip->dev);
	556	if (!handle)
	557	return;
	558
	559	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
	560	if (ACPI_FAILURE(status)) {
	561	dev_warn(chip->dev, "Failed to retrieve ACPI GPIO chip\n");
	562	return;
	563	}
	564
473ed7be	565	acpi_gpiochip_free_regions(acpi_gpio);
aa92b6f6 MW	566
	567	acpi_detach_data(handle, acpi_gpio_chip_dh);
	568	kfree(acpi_gpio);
664e3e5a	569	}