/*
* ec.c - ACPI Embedded Controller Driver (v2.1)
*
* Copyright (C) 2006-2008 Alexey Starikovskiy <astarikovskiy@suse.de>
* 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 printout */
/* #define DEBUG */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <asm/io.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
#include <linux/dmi.h>
#include "internal.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,
};
#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_MSI_UDELAY 550 /* Wait 550us for MSI EC */
enum {
EC_FLAGS_QUERY_PENDING, /* Query is pending */
EC_FLAGS_GPE_STORM, /* GPE storm detected */
EC_FLAGS_HANDLERS_INSTALLED, /* Handlers for GPE and
* OpReg are installed */
EC_FLAGS_BLOCKED, /* Transactions are blocked */
};
/* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
module_param(ec_delay, uint, 0644);
MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
/*
* If the number of false interrupts per one transaction exceeds
* this threshold, will think there is a GPE storm happened and
* will disable the GPE for normal transaction.
*/
static unsigned int ec_storm_threshold __read_mostly = 8;
module_param(ec_storm_threshold, uint, 0644);
MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm");
/* 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;
};
struct transaction {
const u8 *wdata;
u8 *rdata;
unsigned short irq_count;
u8 command;
u8 wi;
u8 ri;
u8 wlen;
u8 rlen;
bool done;
};
struct acpi_ec *boot_ec, *first_ec;
EXPORT_SYMBOL(first_ec);
static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
/* --------------------------------------------------------------------------
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 x;
}
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 int ec_transaction_done(struct acpi_ec *ec)
{
unsigned long flags;
int ret = 0;
spin_lock_irqsave(&ec->curr_lock, flags);
if (!ec->curr || ec->curr->done)
ret = 1;