/*
* acpi_ec.c - ACPI Embedded Controller Driver ($Revision: 38 $)
*
* 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.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#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 <asm/io.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
#include <acpi/actypes.h>
#define _COMPONENT ACPI_EC_COMPONENT
ACPI_MODULE_NAME("acpi_ec")
#define ACPI_EC_COMPONENT 0x00100000
#define ACPI_EC_CLASS "embedded_controller"
#define ACPI_EC_HID "PNP0C09"
#define ACPI_EC_DRIVER_NAME "ACPI Embedded Controller Driver"
#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 */
static enum ec_mode {
EC_INTR = 1, /* Output buffer full */
EC_POLL, /* Input buffer empty */
} acpi_ec_mode = EC_INTR;
static int acpi_ec_remove(struct acpi_device *device, int type);
static int acpi_ec_start(struct acpi_device *device);
static int acpi_ec_stop(struct acpi_device *device, int type);
static int acpi_ec_add(struct acpi_device *device);
static struct acpi_driver acpi_ec_driver = {
.name = ACPI_EC_DRIVER_NAME,
.class = ACPI_EC_CLASS,
.ids = ACPI_EC_HID,
.ops = {
.add = acpi_ec_add,
.remove = acpi_ec_remove,
.start = acpi_ec_start,
.stop = acpi_ec_stop,
},
};
/* If we find an EC via the ECDT, we need to keep a ptr to its context */
static struct acpi_ec {
acpi_handle handle;
unsigned long uid;
unsigned long gpe;
unsigned long command_addr;
unsigned long data_addr;
unsigned long global_lock;
struct mutex lock;
atomic_t query_pending;
atomic_t leaving_burst; /* 0 : No, 1 : Yes, 2: abort */
wait_queue_head_t wait;
} *ec_ecdt;
/* External interfaces use first EC only, so remember */
static struct acpi_device *first_ec;
/* --------------------------------------------------------------------------
Transaction Management
-------------------------------------------------------------------------- */
static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
{
return inb(ec->command_addr);
}
static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
{
return inb(ec->data_addr);
}
static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
{
outb(command, ec->command_addr);
}
static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
{
outb(data, ec->data_addr);
}
static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event)
{
u8 status = acpi_ec_read_status(ec);
if (event == ACPI_EC_EVENT_OBF_1) {
if (status & ACPI_EC_FLAG_OBF)
return 1;
} else if (event == ACPI_EC_EVENT_IBF_0) {
if (!(status & ACPI_EC_FLAG_IBF))
return 1;
}
return 0;
}
static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event)
{
if (acpi_ec_mode == EC_POLL) {
unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
while (time_before(jiffies, delay)) {
if (acpi_ec_check_status(ec, event))
return 0;
}
} else {
if (wait_event_timeout(ec->wait,
acpi_ec_check_status(ec, event),
msecs_t