kernel-ark/drivers/acpi/evged.c
Paul Gortmaker 437014bdac ACPI / GED: make evged.c explicitly non-modular
The Makefile/Kconfig currently controlling compilation of this code is:

Makefile:acpi-$(CONFIG_ACPI_REDUCED_HARDWARE_ONLY) += evged.o

drivers/acpi/Kconfig:config ACPI_REDUCED_HARDWARE_ONLY
drivers/acpi/Kconfig:   bool "Hardware-reduced ACPI support only" if EXPERT

...meaning that it currently is not being built as a module by anyone.

Lets remove the couple traces of modularity so that when reading the
code there is no doubt it is builtin-only.

Since module_platform_driver() uses the same init level priority as
builtin_platform_driver() the init ordering remains unchanged with
this commit.

The file wasn't explicitly including the module.h file but it did
already have init.h so, unlike similar changes, this one has no
header changes at all.

We also delete the MODULE_LICENSE tag since all that information
is already contained at the top of the file in the comments.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-05-09 22:59:25 +02:00

155 lines
3.8 KiB
C

/*
* Generic Event Device for ACPI.
*
* Copyright (c) 2016, The Linux Foundation. All rights reserved.
*
* 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.
*
* 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_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 device *dev = context;
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;
}
dev_info(dev, "GED listening GSI %u @ IRQ %u\n", gsi, irq);
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 (devm_request_threaded_irq(dev, 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;
}
return AE_OK;
}
static int ged_probe(struct platform_device *pdev)
{
acpi_status acpi_ret;
acpi_ret = acpi_walk_resources(ACPI_HANDLE(&pdev->dev), "_CRS",
acpi_ged_request_interrupt, &pdev->dev);
if (ACPI_FAILURE(acpi_ret)) {
dev_err(&pdev->dev, "unable to parse the _CRS record\n");
return -EINVAL;
}
return 0;
}
static const struct acpi_device_id ged_acpi_ids[] = {
{"ACPI0013"},
{},
};
static struct platform_driver ged_driver = {
.probe = ged_probe,
.driver = {
.name = MODULE_NAME,
.acpi_match_table = ACPI_PTR(ged_acpi_ids),
},
};
builtin_platform_driver(ged_driver);