linux-stable/drivers/pnp/pnpacpi/core.c
Zhang Rui eec15edbb0 ACPI / PNP: use device ID list for PNPACPI device enumeration
ACPI can be used to enumerate PNP devices, but the code does not
handle this in the right way currently.  Namely, if an ACPI device
object
 1. Has a _CRS method,
 2. Has an identification of
    "three capital characters followed by four hex digits",
 3. Is not in the excluded IDs list,
it will be enumerated to PNP bus (that is, a PNP device object will
be create for it).  This means that, actually, the PNP bus type is
used as the default bus type for enumerating _HID devices in ACPI.

However, more and more _HID devices need to be enumerated to the
platform bus instead (that is, platform device objects need to be
created for them).  As a result, the device ID list in acpi_platform.c
is used to enforce creating platform device objects rather than PNP
device objects for matching devices.  That list has been continuously
growing recently, unfortunately, and it is pretty much guaranteed to
grow even more in the future.

To address that problem it is better to enumerate _HID devices
as platform devices by default.  To this end, change the way of
enumerating PNP devices by adding a PNP ACPI scan handler that
will use a device ID list to create PNP devices for the ACPI
device objects whose device IDs are present in that list.

The initial device ID list in the PNP ACPI scan handler contains
all of the pnp_device_id strings from all the existing PNP drivers,
so this change should be transparent to the PNP core and all of the
PNP drivers.  Still, in the future it should be possible to reduce
its size by converting PNP drivers that need not be PNP for any
technical reasons into platform drivers.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
[rjw: Rewrote the changelog, modified the PNP ACPI scan handler code]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-05-30 16:04:35 +02:00

379 lines
9.1 KiB
C

/*
* pnpacpi -- PnP ACPI driver
*
* Copyright (c) 2004 Matthieu Castet <castet.matthieu@free.fr>
* Copyright (c) 2004 Li Shaohua <shaohua.li@intel.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2, or (at your option) any
* later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/export.h>
#include <linux/acpi.h>
#include <linux/pnp.h>
#include <linux/slab.h>
#include <linux/mod_devicetable.h>
#include "../base.h"
#include "pnpacpi.h"
static int num;
/*
* Compatible Device IDs
*/
#define TEST_HEX(c) \
if (!(('0' <= (c) && (c) <= '9') || ('A' <= (c) && (c) <= 'F'))) \
return 0
#define TEST_ALPHA(c) \
if (!('A' <= (c) && (c) <= 'Z')) \
return 0
static int __init ispnpidacpi(const char *id)
{
TEST_ALPHA(id[0]);
TEST_ALPHA(id[1]);
TEST_ALPHA(id[2]);
TEST_HEX(id[3]);
TEST_HEX(id[4]);
TEST_HEX(id[5]);
TEST_HEX(id[6]);
if (id[7] != '\0')
return 0;
return 1;
}
static int pnpacpi_get_resources(struct pnp_dev *dev)
{
pnp_dbg(&dev->dev, "get resources\n");
return pnpacpi_parse_allocated_resource(dev);
}
static int pnpacpi_set_resources(struct pnp_dev *dev)
{
struct acpi_device *acpi_dev;
acpi_handle handle;
int ret = 0;
pnp_dbg(&dev->dev, "set resources\n");
handle = ACPI_HANDLE(&dev->dev);
if (!handle || acpi_bus_get_device(handle, &acpi_dev)) {
dev_dbg(&dev->dev, "ACPI device not found in %s!\n", __func__);
return -ENODEV;
}
if (WARN_ON_ONCE(acpi_dev != dev->data))
dev->data = acpi_dev;
if (acpi_has_method(handle, METHOD_NAME__SRS)) {
struct acpi_buffer buffer;
ret = pnpacpi_build_resource_template(dev, &buffer);
if (ret)
return ret;
ret = pnpacpi_encode_resources(dev, &buffer);
if (!ret) {
acpi_status status;
status = acpi_set_current_resources(handle, &buffer);
if (ACPI_FAILURE(status))
ret = -EIO;
}
kfree(buffer.pointer);
}
if (!ret && acpi_bus_power_manageable(handle))
ret = acpi_bus_set_power(handle, ACPI_STATE_D0);
return ret;
}
static int pnpacpi_disable_resources(struct pnp_dev *dev)
{
struct acpi_device *acpi_dev;
acpi_handle handle;
acpi_status status;
dev_dbg(&dev->dev, "disable resources\n");
handle = ACPI_HANDLE(&dev->dev);
if (!handle || acpi_bus_get_device(handle, &acpi_dev)) {
dev_dbg(&dev->dev, "ACPI device not found in %s!\n", __func__);
return 0;
}
/* acpi_unregister_gsi(pnp_irq(dev, 0)); */
if (acpi_bus_power_manageable(handle))
acpi_bus_set_power(handle, ACPI_STATE_D3_COLD);
/* continue even if acpi_bus_set_power() fails */
status = acpi_evaluate_object(handle, "_DIS", NULL, NULL);
if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
return -ENODEV;
return 0;
}
#ifdef CONFIG_ACPI_SLEEP
static bool pnpacpi_can_wakeup(struct pnp_dev *dev)
{
struct acpi_device *acpi_dev;
acpi_handle handle;
handle = ACPI_HANDLE(&dev->dev);
if (!handle || acpi_bus_get_device(handle, &acpi_dev)) {
dev_dbg(&dev->dev, "ACPI device not found in %s!\n", __func__);
return false;
}
return acpi_bus_can_wakeup(handle);
}
static int pnpacpi_suspend(struct pnp_dev *dev, pm_message_t state)
{
struct acpi_device *acpi_dev;
acpi_handle handle;
int error = 0;
handle = ACPI_HANDLE(&dev->dev);
if (!handle || acpi_bus_get_device(handle, &acpi_dev)) {
dev_dbg(&dev->dev, "ACPI device not found in %s!\n", __func__);
return 0;
}
if (device_can_wakeup(&dev->dev)) {
error = acpi_pm_device_sleep_wake(&dev->dev,
device_may_wakeup(&dev->dev));
if (error)
return error;
}
if (acpi_bus_power_manageable(handle)) {
int power_state = acpi_pm_device_sleep_state(&dev->dev, NULL,
ACPI_STATE_D3_COLD);
if (power_state < 0)
power_state = (state.event == PM_EVENT_ON) ?
ACPI_STATE_D0 : ACPI_STATE_D3_COLD;
/*
* acpi_bus_set_power() often fails (keyboard port can't be
* powered-down?), and in any case, our return value is ignored
* by pnp_bus_suspend(). Hence we don't revert the wakeup
* setting if the set_power fails.
*/
error = acpi_bus_set_power(handle, power_state);
}
return error;
}
static int pnpacpi_resume(struct pnp_dev *dev)
{
struct acpi_device *acpi_dev;
acpi_handle handle = ACPI_HANDLE(&dev->dev);
int error = 0;
if (!handle || acpi_bus_get_device(handle, &acpi_dev)) {
dev_dbg(&dev->dev, "ACPI device not found in %s!\n", __func__);
return -ENODEV;
}
if (device_may_wakeup(&dev->dev))
acpi_pm_device_sleep_wake(&dev->dev, false);
if (acpi_bus_power_manageable(handle))
error = acpi_bus_set_power(handle, ACPI_STATE_D0);
return error;
}
#endif
struct pnp_protocol pnpacpi_protocol = {
.name = "Plug and Play ACPI",
.get = pnpacpi_get_resources,
.set = pnpacpi_set_resources,
.disable = pnpacpi_disable_resources,
#ifdef CONFIG_ACPI_SLEEP
.can_wakeup = pnpacpi_can_wakeup,
.suspend = pnpacpi_suspend,
.resume = pnpacpi_resume,
#endif
};
EXPORT_SYMBOL(pnpacpi_protocol);
static char *__init pnpacpi_get_id(struct acpi_device *device)
{
struct acpi_hardware_id *id;
list_for_each_entry(id, &device->pnp.ids, list) {
if (ispnpidacpi(id->id))
return id->id;
}
return NULL;
}
static int __init pnpacpi_add_device(struct acpi_device *device)
{
struct pnp_dev *dev;
char *pnpid;
struct acpi_hardware_id *id;
int error;
/* Skip devices that are already bound */
if (device->physical_node_count)
return 0;
/*
* If a PnPacpi device is not present , the device
* driver should not be loaded.
*/
if (!acpi_has_method(device->handle, "_CRS"))
return 0;
pnpid = pnpacpi_get_id(device);
if (!pnpid)
return 0;
if (!device->status.present)
return 0;
dev = pnp_alloc_dev(&pnpacpi_protocol, num, pnpid);
if (!dev)
return -ENOMEM;
dev->data = device;
/* .enabled means the device can decode the resources */
dev->active = device->status.enabled;
if (acpi_has_method(device->handle, "_SRS"))
dev->capabilities |= PNP_CONFIGURABLE;
dev->capabilities |= PNP_READ;
if (device->flags.dynamic_status && (dev->capabilities & PNP_CONFIGURABLE))
dev->capabilities |= PNP_WRITE;
if (device->flags.removable)
dev->capabilities |= PNP_REMOVABLE;
if (acpi_has_method(device->handle, "_DIS"))
dev->capabilities |= PNP_DISABLE;
if (strlen(acpi_device_name(device)))
strncpy(dev->name, acpi_device_name(device), sizeof(dev->name));
else
strncpy(dev->name, acpi_device_bid(device), sizeof(dev->name));
if (dev->active)
pnpacpi_parse_allocated_resource(dev);
if (dev->capabilities & PNP_CONFIGURABLE)
pnpacpi_parse_resource_option_data(dev);
list_for_each_entry(id, &device->pnp.ids, list) {
if (!strcmp(id->id, pnpid))
continue;
if (!ispnpidacpi(id->id))
continue;
pnp_add_id(dev, id->id);
}
/* clear out the damaged flags */
if (!dev->active)
pnp_init_resources(dev);
error = pnp_add_device(dev);
if (error) {
put_device(&dev->dev);
return error;
}
num++;
return 0;
}
static acpi_status __init pnpacpi_add_device_handler(acpi_handle handle,
u32 lvl, void *context,
void **rv)
{
struct acpi_device *device;
if (acpi_bus_get_device(handle, &device))
return AE_CTRL_DEPTH;
if (acpi_is_pnp_device(device))
pnpacpi_add_device(device);
return AE_OK;
}
static int __init acpi_pnp_match(struct device *dev, void *_pnp)
{
struct acpi_device *acpi = to_acpi_device(dev);
struct pnp_dev *pnp = _pnp;
/* true means it matched */
return !acpi->physical_node_count
&& compare_pnp_id(pnp->id, acpi_device_hid(acpi));
}
static struct acpi_device * __init acpi_pnp_find_companion(struct device *dev)
{
dev = bus_find_device(&acpi_bus_type, NULL, to_pnp_dev(dev),
acpi_pnp_match);
if (!dev)
return NULL;
put_device(dev);
return to_acpi_device(dev);
}
/* complete initialization of a PNPACPI device includes having
* pnpdev->dev.archdata.acpi_handle point to its ACPI sibling.
*/
static bool acpi_pnp_bus_match(struct device *dev)
{
return dev->bus == &pnp_bus_type;
}
static struct acpi_bus_type __initdata acpi_pnp_bus = {
.name = "PNP",
.match = acpi_pnp_bus_match,
.find_companion = acpi_pnp_find_companion,
};
int pnpacpi_disabled __initdata;
static int __init pnpacpi_init(void)
{
if (acpi_disabled || pnpacpi_disabled) {
printk(KERN_INFO "pnp: PnP ACPI: disabled\n");
return 0;
}
printk(KERN_INFO "pnp: PnP ACPI init\n");
pnp_register_protocol(&pnpacpi_protocol);
register_acpi_bus_type(&acpi_pnp_bus);
acpi_get_devices(NULL, pnpacpi_add_device_handler, NULL, NULL);
printk(KERN_INFO "pnp: PnP ACPI: found %d devices\n", num);
unregister_acpi_bus_type(&acpi_pnp_bus);
pnp_platform_devices = 1;
return 0;
}
fs_initcall(pnpacpi_init);
static int __init pnpacpi_setup(char *str)
{
if (str == NULL)
return 1;
if (!strncmp(str, "off", 3))
pnpacpi_disabled = 1;
return 1;
}
__setup("pnpacpi=", pnpacpi_setup);