linux/drivers/acpi/ec.c

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/*
* ec.c - ACPI Embedded Controller Driver (v2.0)
*
* Copyright (C) 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
* Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
* Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@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 of the License, 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.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
/* Uncomment next line to get verbose print outs*/
/* #define DEBUG */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <asm/io.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
#include <acpi/actypes.h>
#define ACPI_EC_CLASS "embedded_controller"
#define ACPI_EC_DEVICE_NAME "Embedded Controller"
#define ACPI_EC_FILE_INFO "info"
#undef PREFIX
#define PREFIX "ACPI: EC: "
/* EC status register */
#define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */
#define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */
#define ACPI_EC_FLAG_BURST 0x10 /* burst mode */
#define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */
/* EC commands */
enum ec_command {
ACPI_EC_COMMAND_READ = 0x80,
ACPI_EC_COMMAND_WRITE = 0x81,
ACPI_EC_BURST_ENABLE = 0x82,
ACPI_EC_BURST_DISABLE = 0x83,
ACPI_EC_COMMAND_QUERY = 0x84,
};
/* EC events */
enum ec_event {
ACPI_EC_EVENT_OBF_1 = 1, /* Output buffer full */
ACPI_EC_EVENT_IBF_0, /* Input buffer empty */
};
#define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */
#define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */
#define ACPI_EC_UDELAY 100 /* Wait 100us before polling EC again */
enum {
EC_FLAGS_WAIT_GPE = 0, /* Don't check status until GPE arrives */
EC_FLAGS_QUERY_PENDING, /* Query is pending */
EC_FLAGS_GPE_MODE, /* Expect GPE to be sent for status change */
EC_FLAGS_NO_GPE, /* Don't use GPE mode */
EC_FLAGS_RESCHEDULE_POLL /* Re-schedule poll */
};
/* If we find an EC via the ECDT, we need to keep a ptr to its context */
/* External interfaces use first EC only, so remember */
typedef int (*acpi_ec_query_func) (void *data);
struct acpi_ec_query_handler {
struct list_head node;
acpi_ec_query_func func;
acpi_handle handle;
void *data;
u8 query_bit;
};
static struct acpi_ec {
acpi_handle handle;
unsigned long gpe;
unsigned long command_addr;
unsigned long data_addr;
unsigned long global_lock;
unsigned long flags;
struct mutex lock;
wait_queue_head_t wait;
struct list_head list;
struct delayed_work work;
atomic_t irq_count;
u8 handlers_installed;
} *boot_ec, *first_ec;
/*
* Some Asus system have exchanged ECDT data/command IO addresses.
*/
static int print_ecdt_error(const struct dmi_system_id *id)
{
printk(KERN_NOTICE PREFIX "%s detected - "
"ECDT has exchanged control/data I/O address\n",
id->ident);
return 0;
}
static struct dmi_system_id __cpuinitdata ec_dmi_table[] = {
{
print_ecdt_error, "Asus L4R", {
DMI_MATCH(DMI_BIOS_VERSION, "1008.006"),
DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),
DMI_MATCH(DMI_BOARD_NAME, "L4R") }, NULL},
{
print_ecdt_error, "Asus M6R", {
DMI_MATCH(DMI_BIOS_VERSION, "0207"),
DMI_MATCH(DMI_PRODUCT_NAME, "M6R"),
DMI_MATCH(DMI_BOARD_NAME, "M6R") }, NULL},
{},
};
/* --------------------------------------------------------------------------
Transaction Management
-------------------------------------------------------------------------- */
static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
{
u8 x = inb(ec->command_addr);
pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
return x;
}
static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
{
u8 x = inb(ec->data_addr);
pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
return inb(ec->data_addr);
}
static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
{
pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
outb(command, ec->command_addr);
}
static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
{
pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
outb(data, ec->data_addr);
}
static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event)
{
if (test_bit(EC_FLAGS_WAIT_GPE, &ec->flags))
return 0;
if (event == ACPI_EC_EVENT_OBF_1) {
if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
return 1;
} else if (event == ACPI_EC_EVENT_IBF_0) {
if (!(acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF))
return 1;
}
return 0;
}
static void ec_schedule_ec_poll(struct acpi_ec *ec)
{
if (test_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags))
schedule_delayed_work(&ec->work,
msecs_to_jiffies(ACPI_EC_DELAY));
}
static void ec_switch_to_poll_mode(struct acpi_ec *ec)
{
set_bit(EC_FLAGS_NO_GPE, &ec->flags);
clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
set_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags);
}
static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, int force_poll)
{
atomic_set(&ec->irq_count, 0);
if (likely(test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) &&
likely(!force_poll)) {
if (wait_event_timeout(ec->wait, acpi_ec_check_status(ec, event),
msecs_to_jiffies(ACPI_EC_DELAY)))
return 0;
clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
if (acpi_ec_check_status(ec, event)) {
/* missing GPEs, switch back to poll mode */
if (printk_ratelimit())
pr_info(PREFIX "missing confirmations, "
"switch off interrupt mode.\n");
ec_switch_to_poll_mode(ec);
ec_schedule_ec_poll(ec);
return 0;
}
} else {
unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
while (time_before(jiffies, delay)) {
if (acpi_ec_check_status(ec, event))
return 0;
msleep(1);
}
ACPI: Avoid bogus EC timeout when EC is in Polling mode When EC is in Polling mode, OS will check the EC status continually by using the following source code: clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags); while (time_before(jiffies, delay)) { if (acpi_ec_check_status(ec, event)) return 0; msleep(1); } But msleep is realized by the function of schedule_timeout. At the same time although one process is already waken up by some events, it won't be scheduled immediately. So maybe there exists the following phenomena: a. The current jiffies is already after the predefined jiffies. But before timeout happens, OS has no chance to check the EC status again. b. If preemptible schedule is enabled, maybe preempt schedule will happen before checking loop. When the process is resumed again, maybe timeout already happens, which means that OS has no chance to check the EC status. In such case maybe EC status is already what OS expects when timeout happens. But OS has no chance to check the EC status and regards it as AE_TIME. So it will be more appropriate that OS will try to check the EC status again when timeout happens. If the EC status is what we expect, it won't be regarded as timeout. Only when the EC status is not what we expect, it will be regarded as timeout, which means that EC controller can't give a response in time. http://bugzilla.kernel.org/show_bug.cgi?id=9823 http://bugzilla.kernel.org/show_bug.cgi?id=11141 Signed-off-by: Zhao Yakui <yakui.zhao@intel.com> Signed-off-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com>
2008-08-11 02:33:31 +00:00
if (acpi_ec_check_status(ec,event))
return 0;
}
pr_err(PREFIX "acpi_ec_wait timeout, status = 0x%2.2x, event = %s\n",
acpi_ec_read_status(ec),
(event == ACPI_EC_EVENT_OBF_1) ? "\"b0=1\"" : "\"b1=0\"");
return -ETIME;
}
static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
const u8 * wdata, unsigned wdata_len,
acpi,msi-laptop: Fall back to EC polling mode for MSI laptop specific EC commands The ACPI EC that is used in MSI laptops knows some non-standard commands for changing the screen brighntess and a few other things, which are used by the msi-laptop.c driver. Unfortunately for these commands no GPE events for IBF and OBF are triggered. Since nowadays the EC code uses the ec_intr=1 mode by default, this causes these operations to timeout, although they don't fail. In result, all operations that you can do with the msi-laptop.c driver take more or less 1s to complete, which is awfully slow. In one of the more recent kernels (2.6.20?) the EC subsystem has been revamped. With that change the EC timeout has been increased. before that increase the MSI EC accesses were slow -- but not *that* slow, hence I took notice of this limitation of the MSI EC hardware only very recently. The standard EC operations on the MSI EC as defined in the ACPI spec support GPE events properly. The following patch adds a new argument "force_poll" to the ec_transaction() function (and friends). If set to 1, the function will poll for IBF/OBF even if ec_intr=1 is enabled. If set to 0 the current behaviour is used. The msi-laptop driver is modified to make use of this new flag, so that OBF/IBF is polled for the special MSI EC transactions -- but only for them. Signed-off-by: Lennart Poettering <mzxreary@0pointer.de> Acked-by: Alexey Starikovskiy <aystarik@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com>
2007-05-04 12:16:19 +00:00
u8 * rdata, unsigned rdata_len,
int force_poll)
{
int result = 0;
set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
pr_debug(PREFIX "transaction start\n");
acpi_ec_write_cmd(ec, command);
for (; wdata_len > 0; --wdata_len) {
result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
if (result) {
pr_err(PREFIX
"write_cmd timeout, command = %d\n", command);
goto end;
}
set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
acpi_ec_write_data(ec, *(wdata++));
}
if (!rdata_len) {
result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
if (result) {
pr_err(PREFIX
"finish-write timeout, command = %d\n", command);
goto end;
}
} else if (command == ACPI_EC_COMMAND_QUERY)
clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
for (; rdata_len > 0; --rdata_len) {
result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, force_poll);
if (result) {
pr_err(PREFIX "read timeout, command = %d\n", command);
goto end;
}
/* Don't expect GPE after last read */
if (rdata_len > 1)
set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
*(rdata++) = acpi_ec_read_data(ec);
}
end:
pr_debug(PREFIX "transaction end\n");
return result;
}
static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
const u8 * wdata, unsigned wdata_len,
acpi,msi-laptop: Fall back to EC polling mode for MSI laptop specific EC commands The ACPI EC that is used in MSI laptops knows some non-standard commands for changing the screen brighntess and a few other things, which are used by the msi-laptop.c driver. Unfortunately for these commands no GPE events for IBF and OBF are triggered. Since nowadays the EC code uses the ec_intr=1 mode by default, this causes these operations to timeout, although they don't fail. In result, all operations that you can do with the msi-laptop.c driver take more or less 1s to complete, which is awfully slow. In one of the more recent kernels (2.6.20?) the EC subsystem has been revamped. With that change the EC timeout has been increased. before that increase the MSI EC accesses were slow -- but not *that* slow, hence I took notice of this limitation of the MSI EC hardware only very recently. The standard EC operations on the MSI EC as defined in the ACPI spec support GPE events properly. The following patch adds a new argument "force_poll" to the ec_transaction() function (and friends). If set to 1, the function will poll for IBF/OBF even if ec_intr=1 is enabled. If set to 0 the current behaviour is used. The msi-laptop driver is modified to make use of this new flag, so that OBF/IBF is polled for the special MSI EC transactions -- but only for them. Signed-off-by: Lennart Poettering <mzxreary@0pointer.de> Acked-by: Alexey Starikovskiy <aystarik@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com>
2007-05-04 12:16:19 +00:00
u8 * rdata, unsigned rdata_len,
int force_poll)
{
int status;
u32 glk;
if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
return -EINVAL;
if (rdata)
memset(rdata, 0, rdata_len);
mutex_lock(&ec->lock);
if (ec->global_lock) {
status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
if (ACPI_FAILURE(status)) {
mutex_unlock(&ec->lock);
return -ENODEV;
}
}
status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0);
if (status) {
pr_err(PREFIX "input buffer is not empty, "
"aborting transaction\n");
goto end;
}
status = acpi_ec_transaction_unlocked(ec, command,
wdata, wdata_len,
acpi,msi-laptop: Fall back to EC polling mode for MSI laptop specific EC commands The ACPI EC that is used in MSI laptops knows some non-standard commands for changing the screen brighntess and a few other things, which are used by the msi-laptop.c driver. Unfortunately for these commands no GPE events for IBF and OBF are triggered. Since nowadays the EC code uses the ec_intr=1 mode by default, this causes these operations to timeout, although they don't fail. In result, all operations that you can do with the msi-laptop.c driver take more or less 1s to complete, which is awfully slow. In one of the more recent kernels (2.6.20?) the EC subsystem has been revamped. With that change the EC timeout has been increased. before that increase the MSI EC accesses were slow -- but not *that* slow, hence I took notice of this limitation of the MSI EC hardware only very recently. The standard EC operations on the MSI EC as defined in the ACPI spec support GPE events properly. The following patch adds a new argument "force_poll" to the ec_transaction() function (and friends). If set to 1, the function will poll for IBF/OBF even if ec_intr=1 is enabled. If set to 0 the current behaviour is used. The msi-laptop driver is modified to make use of this new flag, so that OBF/IBF is polled for the special MSI EC transactions -- but only for them. Signed-off-by: Lennart Poettering <mzxreary@0pointer.de> Acked-by: Alexey Starikovskiy <aystarik@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com>
2007-05-04 12:16:19 +00:00
rdata, rdata_len,
force_poll);
end:
if (ec->global_lock)
acpi_release_global_lock(glk);
mutex_unlock(&ec->lock);
return status;
}
/*
* Note: samsung nv5000 doesn't work with ec burst mode.
* http://bugzilla.kernel.org/show_bug.cgi?id=4980
*/
int acpi_ec_burst_enable(struct acpi_ec *ec)
{
u8 d;
acpi,msi-laptop: Fall back to EC polling mode for MSI laptop specific EC commands The ACPI EC that is used in MSI laptops knows some non-standard commands for changing the screen brighntess and a few other things, which are used by the msi-laptop.c driver. Unfortunately for these commands no GPE events for IBF and OBF are triggered. Since nowadays the EC code uses the ec_intr=1 mode by default, this causes these operations to timeout, although they don't fail. In result, all operations that you can do with the msi-laptop.c driver take more or less 1s to complete, which is awfully slow. In one of the more recent kernels (2.6.20?) the EC subsystem has been revamped. With that change the EC timeout has been increased. before that increase the MSI EC accesses were slow -- but not *that* slow, hence I took notice of this limitation of the MSI EC hardware only very recently. The standard EC operations on the MSI EC as defined in the ACPI spec support GPE events properly. The following patch adds a new argument "force_poll" to the ec_transaction() function (and friends). If set to 1, the function will poll for IBF/OBF even if ec_intr=1 is enabled. If set to 0 the current behaviour is used. The msi-laptop driver is modified to make use of this new flag, so that OBF/IBF is polled for the special MSI EC transactions -- but only for them. Signed-off-by: Lennart Poettering <mzxreary@0pointer.de> Acked-by: Alexey Starikovskiy <aystarik@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com>
2007-05-04 12:16:19 +00:00
return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1, 0);
}
int acpi_ec_burst_disable(struct acpi_ec *ec)
{
acpi,msi-laptop: Fall back to EC polling mode for MSI laptop specific EC commands The ACPI EC that is used in MSI laptops knows some non-standard commands for changing the screen brighntess and a few other things, which are used by the msi-laptop.c driver. Unfortunately for these commands no GPE events for IBF and OBF are triggered. Since nowadays the EC code uses the ec_intr=1 mode by default, this causes these operations to timeout, although they don't fail. In result, all operations that you can do with the msi-laptop.c driver take more or less 1s to complete, which is awfully slow. In one of the more recent kernels (2.6.20?) the EC subsystem has been revamped. With that change the EC timeout has been increased. before that increase the MSI EC accesses were slow -- but not *that* slow, hence I took notice of this limitation of the MSI EC hardware only very recently. The standard EC operations on the MSI EC as defined in the ACPI spec support GPE events properly. The following patch adds a new argument "force_poll" to the ec_transaction() function (and friends). If set to 1, the function will poll for IBF/OBF even if ec_intr=1 is enabled. If set to 0 the current behaviour is used. The msi-laptop driver is modified to make use of this new flag, so that OBF/IBF is polled for the special MSI EC transactions -- but only for them. Signed-off-by: Lennart Poettering <mzxreary@0pointer.de> Acked-by: Alexey Starikovskiy <aystarik@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com>
2007-05-04 12:16:19 +00:00
return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0, 0);
}
static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
{
int result;
u8 d;
result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
acpi,msi-laptop: Fall back to EC polling mode for MSI laptop specific EC commands The ACPI EC that is used in MSI laptops knows some non-standard commands for changing the screen brighntess and a few other things, which are used by the msi-laptop.c driver. Unfortunately for these commands no GPE events for IBF and OBF are triggered. Since nowadays the EC code uses the ec_intr=1 mode by default, this causes these operations to timeout, although they don't fail. In result, all operations that you can do with the msi-laptop.c driver take more or less 1s to complete, which is awfully slow. In one of the more recent kernels (2.6.20?) the EC subsystem has been revamped. With that change the EC timeout has been increased. before that increase the MSI EC accesses were slow -- but not *that* slow, hence I took notice of this limitation of the MSI EC hardware only very recently. The standard EC operations on the MSI EC as defined in the ACPI spec support GPE events properly. The following patch adds a new argument "force_poll" to the ec_transaction() function (and friends). If set to 1, the function will poll for IBF/OBF even if ec_intr=1 is enabled. If set to 0 the current behaviour is used. The msi-laptop driver is modified to make use of this new flag, so that OBF/IBF is polled for the special MSI EC transactions -- but only for them. Signed-off-by: Lennart Poettering <mzxreary@0pointer.de> Acked-by: Alexey Starikovskiy <aystarik@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com>
2007-05-04 12:16:19 +00:00
&address, 1, &d, 1, 0);
*data = d;
return result;
}
static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
{
u8 wdata[2] = { address, data };
return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
acpi,msi-laptop: Fall back to EC polling mode for MSI laptop specific EC commands The ACPI EC that is used in MSI laptops knows some non-standard commands for changing the screen brighntess and a few other things, which are used by the msi-laptop.c driver. Unfortunately for these commands no GPE events for IBF and OBF are triggered. Since nowadays the EC code uses the ec_intr=1 mode by default, this causes these operations to timeout, although they don't fail. In result, all operations that you can do with the msi-laptop.c driver take more or less 1s to complete, which is awfully slow. In one of the more recent kernels (2.6.20?) the EC subsystem has been revamped. With that change the EC timeout has been increased. before that increase the MSI EC accesses were slow -- but not *that* slow, hence I took notice of this limitation of the MSI EC hardware only very recently. The standard EC operations on the MSI EC as defined in the ACPI spec support GPE events properly. The following patch adds a new argument "force_poll" to the ec_transaction() function (and friends). If set to 1, the function will poll for IBF/OBF even if ec_intr=1 is enabled. If set to 0 the current behaviour is used. The msi-laptop driver is modified to make use of this new flag, so that OBF/IBF is polled for the special MSI EC transactions -- but only for them. Signed-off-by: Lennart Poettering <mzxreary@0pointer.de> Acked-by: Alexey Starikovskiy <aystarik@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com>
2007-05-04 12:16:19 +00:00
wdata, 2, NULL, 0, 0);
}
/*
* Externally callable EC access functions. For now, assume 1 EC only
*/
int ec_burst_enable(void)
{
if (!first_ec)
return -ENODEV;
return acpi_ec_burst_enable(first_ec);
}
EXPORT_SYMBOL(ec_burst_enable);
int ec_burst_disable(void)
{
if (!first_ec)
return -ENODEV;
return acpi_ec_burst_disable(first_ec);
}
EXPORT_SYMBOL(ec_burst_disable);
int ec_read(u8 addr, u8 * val)
{
int err;
u8 temp_data;
if (!first_ec)
return -ENODEV;
err = acpi_ec_read(first_ec, addr, &temp_data);
if (!err) {
*val = temp_data;
return 0;
} else
return err;
}
EXPORT_SYMBOL(ec_read);
int ec_write(u8 addr, u8 val)
{
int err;
if (!first_ec)
return -ENODEV;
err = acpi_ec_write(first_ec, addr, val);
return err;
}
EXPORT_SYMBOL(ec_write);
int ec_transaction(u8 command,
const u8 * wdata, unsigned wdata_len,
acpi,msi-laptop: Fall back to EC polling mode for MSI laptop specific EC commands The ACPI EC that is used in MSI laptops knows some non-standard commands for changing the screen brighntess and a few other things, which are used by the msi-laptop.c driver. Unfortunately for these commands no GPE events for IBF and OBF are triggered. Since nowadays the EC code uses the ec_intr=1 mode by default, this causes these operations to timeout, although they don't fail. In result, all operations that you can do with the msi-laptop.c driver take more or less 1s to complete, which is awfully slow. In one of the more recent kernels (2.6.20?) the EC subsystem has been revamped. With that change the EC timeout has been increased. before that increase the MSI EC accesses were slow -- but not *that* slow, hence I took notice of this limitation of the MSI EC hardware only very recently. The standard EC operations on the MSI EC as defined in the ACPI spec support GPE events properly. The following patch adds a new argument "force_poll" to the ec_transaction() function (and friends). If set to 1, the function will poll for IBF/OBF even if ec_intr=1 is enabled. If set to 0 the current behaviour is used. The msi-laptop driver is modified to make use of this new flag, so that OBF/IBF is polled for the special MSI EC transactions -- but only for them. Signed-off-by: Lennart Poettering <mzxreary@0pointer.de> Acked-by: Alexey Starikovskiy <aystarik@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com>
2007-05-04 12:16:19 +00:00
u8 * rdata, unsigned rdata_len,
int force_poll)
{
if (!first_ec)
return -ENODEV;
return acpi_ec_transaction(first_ec, command, wdata,
acpi,msi-laptop: Fall back to EC polling mode for MSI laptop specific EC commands The ACPI EC that is used in MSI laptops knows some non-standard commands for changing the screen brighntess and a few other things, which are used by the msi-laptop.c driver. Unfortunately for these commands no GPE events for IBF and OBF are triggered. Since nowadays the EC code uses the ec_intr=1 mode by default, this causes these operations to timeout, although they don't fail. In result, all operations that you can do with the msi-laptop.c driver take more or less 1s to complete, which is awfully slow. In one of the more recent kernels (2.6.20?) the EC subsystem has been revamped. With that change the EC timeout has been increased. before that increase the MSI EC accesses were slow -- but not *that* slow, hence I took notice of this limitation of the MSI EC hardware only very recently. The standard EC operations on the MSI EC as defined in the ACPI spec support GPE events properly. The following patch adds a new argument "force_poll" to the ec_transaction() function (and friends). If set to 1, the function will poll for IBF/OBF even if ec_intr=1 is enabled. If set to 0 the current behaviour is used. The msi-laptop driver is modified to make use of this new flag, so that OBF/IBF is polled for the special MSI EC transactions -- but only for them. Signed-off-by: Lennart Poettering <mzxreary@0pointer.de> Acked-by: Alexey Starikovskiy <aystarik@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com>
2007-05-04 12:16:19 +00:00
wdata_len, rdata, rdata_len,
force_poll);
}
EXPORT_SYMBOL(ec_transaction);
static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
{
int result;
u8 d;
if (!ec || !data)
return -EINVAL;
/*
* Query the EC to find out which _Qxx method we need to evaluate.
* Note that successful completion of the query causes the ACPI_EC_SCI
* bit to be cleared (and thus clearing the interrupt source).
*/
acpi,msi-laptop: Fall back to EC polling mode for MSI laptop specific EC commands The ACPI EC that is used in MSI laptops knows some non-standard commands for changing the screen brighntess and a few other things, which are used by the msi-laptop.c driver. Unfortunately for these commands no GPE events for IBF and OBF are triggered. Since nowadays the EC code uses the ec_intr=1 mode by default, this causes these operations to timeout, although they don't fail. In result, all operations that you can do with the msi-laptop.c driver take more or less 1s to complete, which is awfully slow. In one of the more recent kernels (2.6.20?) the EC subsystem has been revamped. With that change the EC timeout has been increased. before that increase the MSI EC accesses were slow -- but not *that* slow, hence I took notice of this limitation of the MSI EC hardware only very recently. The standard EC operations on the MSI EC as defined in the ACPI spec support GPE events properly. The following patch adds a new argument "force_poll" to the ec_transaction() function (and friends). If set to 1, the function will poll for IBF/OBF even if ec_intr=1 is enabled. If set to 0 the current behaviour is used. The msi-laptop driver is modified to make use of this new flag, so that OBF/IBF is polled for the special MSI EC transactions -- but only for them. Signed-off-by: Lennart Poettering <mzxreary@0pointer.de> Acked-by: Alexey Starikovskiy <aystarik@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com>
2007-05-04 12:16:19 +00:00
result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1, 0);
if (result)
return result;
if (!d)
return -ENODATA;
*data = d;
return 0;
}
/* --------------------------------------------------------------------------
Event Management
-------------------------------------------------------------------------- */
int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
acpi_handle handle, acpi_ec_query_func func,
void *data)
{
struct acpi_ec_query_handler *handler =
kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
if (!handler)
return -ENOMEM;
handler->query_bit = query_bit;
handler->handle = handle;
handler->func = func;
handler->data = data;
mutex_lock(&ec->lock);
list_add(&handler->node, &ec->list);
mutex_unlock(&ec->lock);
return 0;
}
EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
{
struct acpi_ec_query_handler *handler, *tmp;
mutex_lock(&ec->lock);
list_for_each_entry_safe(handler, tmp, &ec->list, node) {
if (query_bit == handler->query_bit) {
list_del(&handler->node);
kfree(handler);
}
}
mutex_unlock(&ec->lock);
}
EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
static void acpi_ec_gpe_query(void *ec_cxt)
{
struct acpi_ec *ec = ec_cxt;
u8 value = 0;
struct acpi_ec_query_handler *handler, copy;
if (!ec || acpi_ec_query(ec, &value))
return;
mutex_lock(&ec->lock);
list_for_each_entry(handler, &ec->list, node) {
if (value == handler->query_bit) {
/* have custom handler for this bit */
memcpy(&copy, handler, sizeof(copy));
mutex_unlock(&ec->lock);
if (copy.func) {
copy.func(copy.data);
} else if (copy.handle) {
acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
}
return;
}
}
mutex_unlock(&ec->lock);
}
static u32 acpi_ec_gpe_handler(void *data)
{
acpi_status status = AE_OK;
struct acpi_ec *ec = data;
u8 state = acpi_ec_read_status(ec);
acpi,msi-laptop: Fall back to EC polling mode for MSI laptop specific EC commands The ACPI EC that is used in MSI laptops knows some non-standard commands for changing the screen brighntess and a few other things, which are used by the msi-laptop.c driver. Unfortunately for these commands no GPE events for IBF and OBF are triggered. Since nowadays the EC code uses the ec_intr=1 mode by default, this causes these operations to timeout, although they don't fail. In result, all operations that you can do with the msi-laptop.c driver take more or less 1s to complete, which is awfully slow. In one of the more recent kernels (2.6.20?) the EC subsystem has been revamped. With that change the EC timeout has been increased. before that increase the MSI EC accesses were slow -- but not *that* slow, hence I took notice of this limitation of the MSI EC hardware only very recently. The standard EC operations on the MSI EC as defined in the ACPI spec support GPE events properly. The following patch adds a new argument "force_poll" to the ec_transaction() function (and friends). If set to 1, the function will poll for IBF/OBF even if ec_intr=1 is enabled. If set to 0 the current behaviour is used. The msi-laptop driver is modified to make use of this new flag, so that OBF/IBF is polled for the special MSI EC transactions -- but only for them. Signed-off-by: Lennart Poettering <mzxreary@0pointer.de> Acked-by: Alexey Starikovskiy <aystarik@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com>
2007-05-04 12:16:19 +00:00
pr_debug(PREFIX "~~~> interrupt\n");
atomic_inc(&ec->irq_count);
if (atomic_read(&ec->irq_count) > 5) {
pr_err(PREFIX "GPE storm detected, disabling EC GPE\n");
ec_switch_to_poll_mode(ec);
goto end;
}
clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))
wake_up(&ec->wait);
if (state & ACPI_EC_FLAG_SCI) {
if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
status = acpi_os_execute(OSL_EC_BURST_HANDLER,
acpi_ec_gpe_query, ec);
} else if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
!test_bit(EC_FLAGS_NO_GPE, &ec->flags) &&
in_interrupt()) {
/* this is non-query, must be confirmation */
if (printk_ratelimit())
pr_info(PREFIX "non-query interrupt received,"
" switching to interrupt mode\n");
set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
clear_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags);
}
end:
ec_schedule_ec_poll(ec);
return ACPI_SUCCESS(status) ?
ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
}
static void do_ec_poll(struct work_struct *work)
{
struct acpi_ec *ec = container_of(work, struct acpi_ec, work.work);
atomic_set(&ec->irq_count, 0);
(void)acpi_ec_gpe_handler(ec);
}
/* --------------------------------------------------------------------------
Address Space Management
-------------------------------------------------------------------------- */
static acpi_status
acpi_ec_space_handler(u32 function, acpi_physical_address address,
u32 bits, acpi_integer *value,
void *handler_context, void *region_context)
{
struct acpi_ec *ec = handler_context;
int result = 0, i;
u8 temp = 0;
if ((address > 0xFF) || !value || !handler_context)
return AE_BAD_PARAMETER;
if (function != ACPI_READ && function != ACPI_WRITE)
return AE_BAD_PARAMETER;
if (bits != 8 && acpi_strict)
return AE_BAD_PARAMETER;
acpi_ec_burst_enable(ec);
if (function == ACPI_READ) {
result = acpi_ec_read(ec, address, &temp);
*value = temp;
} else {
temp = 0xff & (*value);
result = acpi_ec_write(ec, address, temp);
}
for (i = 8; unlikely(bits - i > 0); i += 8) {
++address;
if (function == ACPI_READ) {
result = acpi_ec_read(ec, address, &temp);
(*value) |= ((acpi_integer)temp) << i;
} else {
temp = 0xff & ((*value) >> i);
result = acpi_ec_write(ec, address, temp);
}
}
acpi_ec_burst_disable(ec);
switch (result) {
case -EINVAL:
return AE_BAD_PARAMETER;
break;
case -ENODEV:
return AE_NOT_FOUND;
break;
case -ETIME:
return AE_TIME;
break;
default:
return AE_OK;
}
}
/* --------------------------------------------------------------------------
FS Interface (/proc)
-------------------------------------------------------------------------- */
static struct proc_dir_entry *acpi_ec_dir;
static int acpi_ec_read_info(struct seq_file *seq, void *offset)
{
struct acpi_ec *ec = seq->private;
if (!ec)
goto end;
seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
(unsigned)ec->command_addr, (unsigned)ec->data_addr);
seq_printf(seq, "use global lock:\t%s\n",
ec->global_lock ? "yes" : "no");
end:
return 0;
}
static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
{
return single_open(file, acpi_ec_read_info, PDE(inode)->data);
}
static struct file_operations acpi_ec_info_ops = {
.open = acpi_ec_info_open_fs,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
.owner = THIS_MODULE,
};
static int acpi_ec_add_fs(struct acpi_device *device)
{
struct proc_dir_entry *entry = NULL;
if (!acpi_device_dir(device)) {
acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
acpi_ec_dir);
if (!acpi_device_dir(device))
return -ENODEV;
}
entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
acpi_device_dir(device),
&acpi_ec_info_ops, acpi_driver_data(device));
if (!entry)
return -ENODEV;
return 0;
}
static int acpi_ec_remove_fs(struct acpi_device *device)
{
if (acpi_device_dir(device)) {
remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
acpi_device_dir(device) = NULL;
}
return 0;
}
/* --------------------------------------------------------------------------
Driver Interface
-------------------------------------------------------------------------- */
static acpi_status
ec_parse_io_ports(struct acpi_resource *resource, void *context);
static struct acpi_ec *make_acpi_ec(void)
{
struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
if (!ec)
return NULL;
ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
mutex_init(&ec->lock);
init_waitqueue_head(&ec->wait);
INIT_LIST_HEAD(&ec->list);
INIT_DELAYED_WORK_DEFERRABLE(&ec->work, do_ec_poll);
atomic_set(&ec->irq_count, 0);
return ec;
}
static acpi_status
acpi_ec_register_query_methods(acpi_handle handle, u32 level,
void *context, void **return_value)
{
struct acpi_namespace_node *node = handle;
struct acpi_ec *ec = context;
int value = 0;
if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
}
return AE_OK;
}
static acpi_status
ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
{
acpi_status status;
struct acpi_ec *ec = context;
status = acpi_walk_resources(handle, METHOD_NAME__CRS,
ec_parse_io_ports, ec);
if (ACPI_FAILURE(status))
return status;
/* Get GPE bit assignment (EC events). */
/* TODO: Add support for _GPE returning a package */
status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
if (ACPI_FAILURE(status))
return status;
/* Use the global lock for all EC transactions? */
acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
ec->handle = handle;
return AE_CTRL_TERMINATE;
}
static void ec_poll_stop(struct acpi_ec *ec)
{
clear_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags);
cancel_delayed_work(&ec->work);
}
static void ec_remove_handlers(struct acpi_ec *ec)
{
ec_poll_stop(ec);
if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
pr_err(PREFIX "failed to remove space handler\n");
if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
&acpi_ec_gpe_handler)))
pr_err(PREFIX "failed to remove gpe handler\n");
ec->handlers_installed = 0;
}
static int acpi_ec_add(struct acpi_device *device)
{
struct acpi_ec *ec = NULL;
if (!device)
return -EINVAL;
strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
strcpy(acpi_device_class(device), ACPI_EC_CLASS);
/* Check for boot EC */
if (boot_ec &&
(boot_ec->handle == device->handle ||
boot_ec->handle == ACPI_ROOT_OBJECT)) {
ec = boot_ec;
boot_ec = NULL;
} else {
ec = make_acpi_ec();
if (!ec)
return -ENOMEM;
if (ec_parse_device(device->handle, 0, ec, NULL) !=
AE_CTRL_TERMINATE) {
kfree(ec);
return -EINVAL;
}
}
ec->handle = device->handle;
/* Find and register all query methods */
acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
acpi_ec_register_query_methods, ec, NULL);
if (!first_ec)
first_ec = ec;
acpi_driver_data(device) = ec;
acpi_ec_add_fs(device);
pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
ec->gpe, ec->command_addr, ec->data_addr);
pr_info(PREFIX "driver started in %s mode\n",
(test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
return 0;
}
static int acpi_ec_remove(struct acpi_device *device, int type)
{
struct acpi_ec *ec;
struct acpi_ec_query_handler *handler, *tmp;
if (!device)
return -EINVAL;
ec = acpi_driver_data(device);
mutex_lock(&ec->lock);
list_for_each_entry_safe(handler, tmp, &ec->list, node) {
list_del(&handler->node);
kfree(handler);
}
mutex_unlock(&ec->lock);
acpi_ec_remove_fs(device);
acpi_driver_data(device) = NULL;
if (ec == first_ec)
first_ec = NULL;
kfree(ec);
return 0;
}
static acpi_status
ec_parse_io_ports(struct acpi_resource *resource, void *context)
{
struct acpi_ec *ec = context;
if (resource->type != ACPI_RESOURCE_TYPE_IO)
return AE_OK;
/*
* The first address region returned is the data port, and
* the second address region returned is the status/command
* port.
*/
if (ec->data_addr == 0)
ec->data_addr = resource->data.io.minimum;
else if (ec->command_addr == 0)
ec->command_addr = resource->data.io.minimum;
else
return AE_CTRL_TERMINATE;
return AE_OK;
}
static int ec_install_handlers(struct acpi_ec *ec)
{
acpi_status status;
if (ec->handlers_installed)
return 0;
status = acpi_install_gpe_handler(NULL, ec->gpe,
ACPI_GPE_EDGE_TRIGGERED,
&acpi_ec_gpe_handler, ec);
if (ACPI_FAILURE(status))
return -ENODEV;
acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
status = acpi_install_address_space_handler(ec->handle,
ACPI_ADR_SPACE_EC,
&acpi_ec_space_handler,
NULL, ec);
if (ACPI_FAILURE(status)) {
acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
return -ENODEV;
}
ec->handlers_installed = 1;
return 0;
}
static int acpi_ec_start(struct acpi_device *device)
{
struct acpi_ec *ec;
int ret = 0;
if (!device)
return -EINVAL;
ec = acpi_driver_data(device);
if (!ec)
return -EINVAL;
ret = ec_install_handlers(ec);
/* EC is fully operational, allow queries */
clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
ec_schedule_ec_poll(ec);
return ret;
}
static int acpi_ec_stop(struct acpi_device *device, int type)
{
struct acpi_ec *ec;
if (!device)
return -EINVAL;
ec = acpi_driver_data(device);
if (!ec)
return -EINVAL;
ec_remove_handlers(ec);
return 0;
}
int __init acpi_boot_ec_enable(void)
{
if (!boot_ec || boot_ec->handlers_installed)
return 0;
if (!ec_install_handlers(boot_ec)) {
first_ec = boot_ec;
return 0;
}
return -EFAULT;
}
static const struct acpi_device_id ec_device_ids[] = {
{"PNP0C09", 0},
{"", 0},
};
int __init acpi_ec_ecdt_probe(void)
{
int ret;
acpi_status status;
struct acpi_table_ecdt *ecdt_ptr;
boot_ec = make_acpi_ec();
if (!boot_ec)
return -ENOMEM;
/*
* Generate a boot ec context
*/
status = acpi_get_table(ACPI_SIG_ECDT, 1,
(struct acpi_table_header **)&ecdt_ptr);
if (ACPI_SUCCESS(status)) {
pr_info(PREFIX "EC description table is found, configuring boot EC\n");
boot_ec->command_addr = ecdt_ptr->control.address;
boot_ec->data_addr = ecdt_ptr->data.address;
if (dmi_check_system(ec_dmi_table)) {
/*
* If the board falls into ec_dmi_table, it means
* that ECDT table gives the incorrect command/status
* & data I/O address. Just fix it.
*/
boot_ec->data_addr = ecdt_ptr->control.address;
boot_ec->command_addr = ecdt_ptr->data.address;
}
boot_ec->gpe = ecdt_ptr->gpe;
boot_ec->handle = ACPI_ROOT_OBJECT;
acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
} else {
/* This workaround is needed only on some broken machines,
* which require early EC, but fail to provide ECDT */
acpi_handle x;
printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
boot_ec, NULL);
/* Check that acpi_get_devices actually find something */
if (ACPI_FAILURE(status) || !boot_ec->handle)
goto error;
/* We really need to limit this workaround, the only ASUS,
* which needs it, has fake EC._INI method, so use it as flag.
* Keep boot_ec struct as it will be needed soon.
*/
if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
return -ENODEV;
}
ret = ec_install_handlers(boot_ec);
if (!ret) {
first_ec = boot_ec;
return 0;
}
error:
kfree(boot_ec);
boot_ec = NULL;
return -ENODEV;
}
static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
{
struct acpi_ec *ec = acpi_driver_data(device);
/* Stop using GPE */
set_bit(EC_FLAGS_NO_GPE, &ec->flags);
clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
return 0;
}
static int acpi_ec_resume(struct acpi_device *device)
{
struct acpi_ec *ec = acpi_driver_data(device);
/* Enable use of GPE back */
clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
return 0;
}
static struct acpi_driver acpi_ec_driver = {
.name = "ec",
.class = ACPI_EC_CLASS,
.ids = ec_device_ids,
.ops = {
.add = acpi_ec_add,
.remove = acpi_ec_remove,
.start = acpi_ec_start,
.stop = acpi_ec_stop,
.suspend = acpi_ec_suspend,
.resume = acpi_ec_resume,
},
};
static int __init acpi_ec_init(void)
{
int result = 0;
if (acpi_disabled)
return 0;
acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
if (!acpi_ec_dir)
return -ENODEV;
/* Now register the driver for the EC */
result = acpi_bus_register_driver(&acpi_ec_driver);
if (result < 0) {
remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
return -ENODEV;
}
return result;
}
subsys_initcall(acpi_ec_init);
/* EC driver currently not unloadable */
#if 0
static void __exit acpi_ec_exit(void)
{
acpi_bus_unregister_driver(&acpi_ec_driver);
remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
return;
}
#endif /* 0 */