linux/drivers/acpi/evged.c
Thomas Gleixner 97fb5e8d9b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 284
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 and
  only version 2 as published by the free software foundation this
  program is distributed in the hope that it will be useful but
  without any warranty without even the implied warranty of
  merchantability or fitness for a particular purpose see the gnu
  general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 294 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.825281744@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:37 +02:00

181 lines
4.2 KiB
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);