[linux-2.6-block.git] / drivers / acpi / evged.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Generic Event Device for ACPI.
 *
 * Copyright (c) 2016, The Linux Foundation. All rights reserved.
 *
 * Generic Event Device allows platforms to handle interrupts in ACPI
 * ASL statements. It follows very similar to  _EVT method approach
 * from GPIO events. All interrupts are listed in _CRS and the handler
 * is written in _EVT method. Here is an example.
 *
 * Device (GED0)
 * {
 *
 *     Name (_HID, "ACPI0013")
 *     Name (_UID, 0)
 *     Method (_CRS, 0x0, Serialized)
 *     {
 *		Name (RBUF, ResourceTemplate ()
 *		{
 *		Interrupt(ResourceConsumer, Edge, ActiveHigh, Shared, , , )
 *		{123}
 *		}
 *     })
 *
 *     Method (_EVT, 1) {
 *             if (Lequal(123, Arg0))
 *             {
 *             }
 *     }
 * }
 */

#include <linux/err.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/platform_device.h>
#include <linux/acpi.h>

#define MODULE_NAME	"acpi-ged"

struct acpi_ged_device {
	struct device *dev;
	struct list_head event_list;
};

struct acpi_ged_event {
	struct list_head node;
	struct device *dev;
	unsigned int gsi;
	unsigned int irq;
	acpi_handle handle;
};

static irqreturn_t acpi_ged_irq_handler(int irq, void *data)
{
	struct acpi_ged_event *event = data;
	acpi_status acpi_ret;

	acpi_ret = acpi_execute_simple_method(event->handle, NULL, event->gsi);
	if (ACPI_FAILURE(acpi_ret))
		dev_err_once(event->dev, "IRQ method execution failed\n");

	return IRQ_HANDLED;
}

static acpi_status acpi_ged_request_interrupt(struct acpi_resource *ares,
					      void *context)
{
	struct acpi_ged_event *event;
	unsigned int irq;
	unsigned int gsi;
	unsigned int irqflags = IRQF_ONESHOT;
	struct acpi_ged_device *geddev = context;
	struct device *dev = geddev->dev;
	acpi_handle handle = ACPI_HANDLE(dev);
	acpi_handle evt_handle;
	struct resource r;
	struct acpi_resource_irq *p = &ares->data.irq;
	struct acpi_resource_extended_irq *pext = &ares->data.extended_irq;

	if (ares->type == ACPI_RESOURCE_TYPE_END_TAG)
		return AE_OK;

	if (!acpi_dev_resource_interrupt(ares, 0, &r)) {
		dev_err(dev, "unable to parse IRQ resource\n");
		return AE_ERROR;
	}
	if (ares->type == ACPI_RESOURCE_TYPE_IRQ)
		gsi = p->interrupts[0];
	else
		gsi = pext->interrupts[0];

	irq = r.start;

	if (ACPI_FAILURE(acpi_get_handle(handle, "_EVT", &evt_handle))) {
		dev_err(dev, "cannot locate _EVT method\n");
		return AE_ERROR;
	}

	event = devm_kzalloc(dev, sizeof(*event), GFP_KERNEL);
	if (!event)
		return AE_ERROR;

	event->gsi = gsi;
	event->dev = dev;
	event->irq = irq;
	event->handle = evt_handle;

	if (r.flags & IORESOURCE_IRQ_SHAREABLE)
		irqflags |= IRQF_SHARED;

	if (request_threaded_irq(irq, NULL, acpi_ged_irq_handler,
				 irqflags, "ACPI:Ged", event)) {
		dev_err(dev, "failed to setup event handler for irq %u\n", irq);
		return AE_ERROR;
	}

	dev_dbg(dev, "GED listening GSI %u @ IRQ %u\n", gsi, irq);
	list_add_tail(&event->node, &geddev->event_list);
	return AE_OK;
}

static int ged_probe(struct platform_device *pdev)
{
	struct acpi_ged_device *geddev;
	acpi_status acpi_ret;

	geddev = devm_kzalloc(&pdev->dev, sizeof(*geddev), GFP_KERNEL);
	if (!geddev)
		return -ENOMEM;

	geddev->dev = &pdev->dev;
	INIT_LIST_HEAD(&geddev->event_list);
	acpi_ret = acpi_walk_resources(ACPI_HANDLE(&pdev->dev), "_CRS",
				       acpi_ged_request_interrupt, geddev);
	if (ACPI_FAILURE(acpi_ret)) {
		dev_err(&pdev->dev, "unable to parse the _CRS record\n");
		return -EINVAL;
	}
	platform_set_drvdata(pdev, geddev);

	return 0;
}

static void ged_shutdown(struct platform_device *pdev)
{
	struct acpi_ged_device *geddev = platform_get_drvdata(pdev);
	struct acpi_ged_event *event, *next;

	list_for_each_entry_safe(event, next, &geddev->event_list, node) {
		free_irq(event->irq, event);
		list_del(&event->node);
		dev_dbg(geddev->dev, "GED releasing GSI %u @ IRQ %u\n",
			 event->gsi, event->irq);
	}
}

static int ged_remove(struct platform_device *pdev)
{
	ged_shutdown(pdev);
	return 0;
}

static const struct acpi_device_id ged_acpi_ids[] = {
	{"ACPI0013"},
	{},
};

static struct platform_driver ged_driver = {
	.probe = ged_probe,
	.remove = ged_remove,
	.shutdown = ged_shutdown,
	.driver = {
		.name = MODULE_NAME,
		.acpi_match_table = ACPI_PTR(ged_acpi_ids),
	},
};
builtin_platform_driver(ged_driver);
Commit	Line	Data
97fb5e8d	1	// SPDX-License-Identifier: GPL-2.0-only
3db80c23 SK	2	/*
	3	* Generic Event Device for ACPI.
	4	*
	5	* Copyright (c) 2016, The Linux Foundation. All rights reserved.
	6	*
3db80c23 SK	7	* Generic Event Device allows platforms to handle interrupts in ACPI
	8	* ASL statements. It follows very similar to _EVT method approach
	9	* from GPIO events. All interrupts are listed in _CRS and the handler
	10	* is written in _EVT method. Here is an example.
	11	*
	12	* Device (GED0)
	13	* {
	14	*
	15	* Name (_HID, "ACPI0013")
	16	* Name (_UID, 0)
	17	* Method (_CRS, 0x0, Serialized)
	18	* {
	19	* Name (RBUF, ResourceTemplate ()
	20	* {
	21	* Interrupt(ResourceConsumer, Edge, ActiveHigh, Shared, , , )
	22	* {123}
	23	* }
	24	* })
	25	*
	26	* Method (_EVT, 1) {
	27	* if (Lequal(123, Arg0))
	28	* {
	29	* }
	30	* }
	31	* }
3db80c23 SK	32	*/
	33
	34	#include <linux/err.h>
	35	#include <linux/init.h>
	36	#include <linux/interrupt.h>
	37	#include <linux/list.h>
	38	#include <linux/platform_device.h>
	39	#include <linux/acpi.h>
	40
	41	#define MODULE_NAME "acpi-ged"
	42
099caa91 SK	43	struct acpi_ged_device {
	44	struct device *dev;
	45	struct list_head event_list;
	46	};
	47
3db80c23 SK	48	struct acpi_ged_event {
	49	struct list_head node;
	50	struct device *dev;
	51	unsigned int gsi;
	52	unsigned int irq;
	53	acpi_handle handle;
	54	};
	55
	56	static irqreturn_t acpi_ged_irq_handler(int irq, void *data)
	57	{
	58	struct acpi_ged_event *event = data;
	59	acpi_status acpi_ret;
	60
	61	acpi_ret = acpi_execute_simple_method(event->handle, NULL, event->gsi);
	62	if (ACPI_FAILURE(acpi_ret))
	63	dev_err_once(event->dev, "IRQ method execution failed\n");
	64
	65	return IRQ_HANDLED;
	66	}
	67
	68	static acpi_status acpi_ged_request_interrupt(struct acpi_resource *ares,
	69	void *context)
	70	{
	71	struct acpi_ged_event *event;
	72	unsigned int irq;
	73	unsigned int gsi;
	74	unsigned int irqflags = IRQF_ONESHOT;
099caa91 SK	75	struct acpi_ged_device *geddev = context;
099caa91 SK	76	struct device *dev = geddev->dev;
3db80c23 SK	77	acpi_handle handle = ACPI_HANDLE(dev);
	78	acpi_handle evt_handle;
	79	struct resource r;
	80	struct acpi_resource_irq *p = &ares->data.irq;
	81	struct acpi_resource_extended_irq *pext = &ares->data.extended_irq;
	82
	83	if (ares->type == ACPI_RESOURCE_TYPE_END_TAG)
	84	return AE_OK;
	85
	86	if (!acpi_dev_resource_interrupt(ares, 0, &r)) {
	87	dev_err(dev, "unable to parse IRQ resource\n");
	88	return AE_ERROR;
	89	}
	90	if (ares->type == ACPI_RESOURCE_TYPE_IRQ)
	91	gsi = p->interrupts[0];
	92	else
	93	gsi = pext->interrupts[0];
	94
	95	irq = r.start;
	96
	97	if (ACPI_FAILURE(acpi_get_handle(handle, "_EVT", &evt_handle))) {
	98	dev_err(dev, "cannot locate _EVT method\n");
	99	return AE_ERROR;
	100	}
	101
3db80c23 SK	102	event = devm_kzalloc(dev, sizeof(*event), GFP_KERNEL);
	103	if (!event)
	104	return AE_ERROR;
	105
	106	event->gsi = gsi;
	107	event->dev = dev;
	108	event->irq = irq;
	109	event->handle = evt_handle;
	110
	111	if (r.flags & IORESOURCE_IRQ_SHAREABLE)
	112	irqflags \|= IRQF_SHARED;
	113
099caa91 SK	114	if (request_threaded_irq(irq, NULL, acpi_ged_irq_handler,
099caa91 SK	115	irqflags, "ACPI:Ged", event)) {
3db80c23 SK	116	dev_err(dev, "failed to setup event handler for irq %u\n", irq);
	117	return AE_ERROR;
	118	}
	119
099caa91 SK	120	dev_dbg(dev, "GED listening GSI %u @ IRQ %u\n", gsi, irq);
099caa91 SK	121	list_add_tail(&event->node, &geddev->event_list);
3db80c23 SK	122	return AE_OK;
	123	}
	124
	125	static int ged_probe(struct platform_device *pdev)
	126	{
099caa91	127	struct acpi_ged_device *geddev;
3db80c23 SK	128	acpi_status acpi_ret;
3db80c23 SK	129
099caa91 SK	130	geddev = devm_kzalloc(&pdev->dev, sizeof(*geddev), GFP_KERNEL);
	131	if (!geddev)
	132	return -ENOMEM;
	133
	134	geddev->dev = &pdev->dev;
	135	INIT_LIST_HEAD(&geddev->event_list);
3db80c23	136	acpi_ret = acpi_walk_resources(ACPI_HANDLE(&pdev->dev), "_CRS",
099caa91	137	acpi_ged_request_interrupt, geddev);
3db80c23 SK	138	if (ACPI_FAILURE(acpi_ret)) {
	139	dev_err(&pdev->dev, "unable to parse the _CRS record\n");
	140	return -EINVAL;
	141	}
099caa91	142	platform_set_drvdata(pdev, geddev);
3db80c23 SK	143
	144	return 0;
	145	}
	146
099caa91 SK	147	static void ged_shutdown(struct platform_device *pdev)
	148	{
	149	struct acpi_ged_device *geddev = platform_get_drvdata(pdev);
	150	struct acpi_ged_event event, next;
	151
	152	list_for_each_entry_safe(event, next, &geddev->event_list, node) {
	153	free_irq(event->irq, event);
	154	list_del(&event->node);
	155	dev_dbg(geddev->dev, "GED releasing GSI %u @ IRQ %u\n",
	156	event->gsi, event->irq);
	157	}
	158	}
	159
	160	static int ged_remove(struct platform_device *pdev)
	161	{
	162	ged_shutdown(pdev);
	163	return 0;
	164	}
	165
3db80c23 SK	166	static const struct acpi_device_id ged_acpi_ids[] = {
	167	{"ACPI0013"},
	168	{},
	169	};
	170
	171	static struct platform_driver ged_driver = {
	172	.probe = ged_probe,
099caa91 SK	173	.remove = ged_remove,
099caa91 SK	174	.shutdown = ged_shutdown,
3db80c23 SK	175	.driver = {
	176	.name = MODULE_NAME,
	177	.acpi_match_table = ACPI_PTR(ged_acpi_ids),
	178	},
	179	};
437014bd	180	builtin_platform_driver(ged_driver);