2 * Generic Event Device for ACPI.
4 * Copyright (c) 2016, The Linux Foundation. All rights reserved.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 and
8 * only version 2 as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * Generic Event Device allows platforms to handle interrupts in ACPI
16 * ASL statements. It follows very similar to _EVT method approach
17 * from GPIO events. All interrupts are listed in _CRS and the handler
18 * is written in _EVT method. Here is an example.
23 * Name (_HID, "ACPI0013")
25 * Method (_CRS, 0x0, Serialized)
27 * Name (RBUF, ResourceTemplate ()
29 * Interrupt(ResourceConsumer, Edge, ActiveHigh, Shared, , , )
35 * if (Lequal(123, Arg0))
43 #include <linux/err.h>
44 #include <linux/init.h>
45 #include <linux/interrupt.h>
46 #include <linux/list.h>
47 #include <linux/platform_device.h>
48 #include <linux/acpi.h>
50 #define MODULE_NAME "acpi-ged"
52 struct acpi_ged_device {
54 struct list_head event_list;
57 struct acpi_ged_event {
58 struct list_head node;
65 static irqreturn_t acpi_ged_irq_handler(int irq, void *data)
67 struct acpi_ged_event *event = data;
70 acpi_ret = acpi_execute_simple_method(event->handle, NULL, event->gsi);
71 if (ACPI_FAILURE(acpi_ret))
72 dev_err_once(event->dev, "IRQ method execution failed\n");
77 static acpi_status acpi_ged_request_interrupt(struct acpi_resource *ares,
80 struct acpi_ged_event *event;
83 unsigned int irqflags = IRQF_ONESHOT;
84 struct acpi_ged_device *geddev = context;
85 struct device *dev = geddev->dev;
86 acpi_handle handle = ACPI_HANDLE(dev);
87 acpi_handle evt_handle;
89 struct acpi_resource_irq *p = &ares->data.irq;
90 struct acpi_resource_extended_irq *pext = &ares->data.extended_irq;
94 if (ares->type == ACPI_RESOURCE_TYPE_END_TAG)
97 if (!acpi_dev_resource_interrupt(ares, 0, &r)) {
98 dev_err(dev, "unable to parse IRQ resource\n");
101 if (ares->type == ACPI_RESOURCE_TYPE_IRQ) {
102 gsi = p->interrupts[0];
103 trigger = p->triggering;
105 gsi = pext->interrupts[0];
106 trigger = pext->triggering;
113 sprintf(ev_name, "_%c%02X",
114 trigger == ACPI_EDGE_SENSITIVE ? 'E' : 'L', gsi);
116 if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
120 if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
123 dev_err(dev, "cannot locate _EVT method\n");
127 event = devm_kzalloc(dev, sizeof(*event), GFP_KERNEL);
134 event->handle = evt_handle;
136 if (r.flags & IORESOURCE_IRQ_SHAREABLE)
137 irqflags |= IRQF_SHARED;
139 if (request_threaded_irq(irq, NULL, acpi_ged_irq_handler,
140 irqflags, "ACPI:Ged", event)) {
141 dev_err(dev, "failed to setup event handler for irq %u\n", irq);
145 dev_dbg(dev, "GED listening GSI %u @ IRQ %u\n", gsi, irq);
146 list_add_tail(&event->node, &geddev->event_list);
150 static int ged_probe(struct platform_device *pdev)
152 struct acpi_ged_device *geddev;
153 acpi_status acpi_ret;
155 geddev = devm_kzalloc(&pdev->dev, sizeof(*geddev), GFP_KERNEL);
159 geddev->dev = &pdev->dev;
160 INIT_LIST_HEAD(&geddev->event_list);
161 acpi_ret = acpi_walk_resources(ACPI_HANDLE(&pdev->dev), "_CRS",
162 acpi_ged_request_interrupt, geddev);
163 if (ACPI_FAILURE(acpi_ret)) {
164 dev_err(&pdev->dev, "unable to parse the _CRS record\n");
167 platform_set_drvdata(pdev, geddev);
172 static void ged_shutdown(struct platform_device *pdev)
174 struct acpi_ged_device *geddev = platform_get_drvdata(pdev);
175 struct acpi_ged_event *event, *next;
177 list_for_each_entry_safe(event, next, &geddev->event_list, node) {
178 free_irq(event->irq, event);
179 list_del(&event->node);
180 dev_dbg(geddev->dev, "GED releasing GSI %u @ IRQ %u\n",
181 event->gsi, event->irq);
185 static int ged_remove(struct platform_device *pdev)
191 static const struct acpi_device_id ged_acpi_ids[] = {
196 static struct platform_driver ged_driver = {
198 .remove = ged_remove,
199 .shutdown = ged_shutdown,
202 .acpi_match_table = ACPI_PTR(ged_acpi_ids),
205 builtin_platform_driver(ged_driver);