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linux-hardened/drivers/acpi/ec.c
Lv Zheng 770970f0b4 ACPI / EC: Add GPE reference counting debugging messages. 
This patch enhances debugging with the GPE reference count messages added.

This kind of log entries can be used by the platform validators to validate
if there is an EC transaction broken because of firmware/driver bugs.

No functional changes.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-03-10 00:58:37 +01:00

1456 lines
38 KiB
C
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/*
* ec.c - ACPI Embedded Controller Driver (v3)
*
* Copyright (C) 2001-2015 Intel Corporation
* Author: 2014, 2015 Lv Zheng <lv.zheng@intel.com>
* 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
* 2006 Denis Sadykov <denis.m.sadykov@intel.com>
* 2004 Luming Yu <luming.yu@intel.com>
* 2001, 2002 Andy Grover <andrew.grover@intel.com>
* 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
* Copyright (C) 2008 Alexey Starikovskiy <astarikovskiy@suse.de>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* 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 */
#define pr_fmt(fmt) "ACPI : EC: " fmt
#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 <linux/acpi.h>
#include <linux/dmi.h>
#include <asm/io.h>
#include "internal.h"
#define ACPI_EC_CLASS "embedded_controller"
#define ACPI_EC_DEVICE_NAME "Embedded Controller"
#define ACPI_EC_FILE_INFO "info"
/* 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_CMD 0x08 /* Input buffer contains a command */
#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 */
#define ACPI_EC_UDELAY_POLL 1000 /* Wait 1ms for EC transaction polling */
#define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query
* when trying to clear the EC */
enum {
EC_FLAGS_QUERY_PENDING, /* Query is pending */
EC_FLAGS_HANDLERS_INSTALLED, /* Handlers for GPE and
* OpReg are installed */
EC_FLAGS_STARTED, /* Driver is started */
EC_FLAGS_STOPPED, /* Driver is stopped */
EC_FLAGS_COMMAND_STORM, /* GPE storms occurred to the
* current command processing */
};
#define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */
#define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */
/* 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");
struct acpi_ec_query_handler {
struct list_head node;
acpi_ec_query_func func;
acpi_handle handle;
void *data;
u8 query_bit;
struct kref kref;
};
struct transaction {
const u8 *wdata;
u8 *rdata;
unsigned short irq_count;
u8 command;
u8 wi;
u8 ri;
u8 wlen;
u8 rlen;
u8 flags;
unsigned long timestamp;
};
static int acpi_ec_query(struct acpi_ec *ec, u8 *data);
static void advance_transaction(struct acpi_ec *ec);
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 */
static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */
static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */
/* --------------------------------------------------------------------------
* Logging/Debugging
* -------------------------------------------------------------------------- */
/*
* Splitters used by the developers to track the boundary of the EC
* handling processes.
*/
#ifdef DEBUG
#define EC_DBG_SEP " "
#define EC_DBG_DRV "+++++"
#define EC_DBG_STM "====="
#define EC_DBG_REQ "*****"
#define EC_DBG_EVT "#####"
#else
#define EC_DBG_SEP ""
#define EC_DBG_DRV
#define EC_DBG_STM
#define EC_DBG_REQ
#define EC_DBG_EVT
#endif
#define ec_log_raw(fmt, ...) \
pr_info(fmt "\n", ##__VA_ARGS__)
#define ec_dbg_raw(fmt, ...) \
pr_debug(fmt "\n", ##__VA_ARGS__)
#define ec_log(filter, fmt, ...) \
ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
#define ec_dbg(filter, fmt, ...) \
ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
#define ec_log_drv(fmt, ...) \
ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__)
#define ec_dbg_drv(fmt, ...) \
ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__)
#define ec_dbg_stm(fmt, ...) \
ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__)
#define ec_dbg_req(fmt, ...) \
ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__)
#define ec_dbg_evt(fmt, ...) \
ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__)
#define ec_dbg_ref(ec, fmt, ...) \
ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__)
/* --------------------------------------------------------------------------
* Device Flags
* -------------------------------------------------------------------------- */
static bool acpi_ec_started(struct acpi_ec *ec)
{
return test_bit(EC_FLAGS_STARTED, &ec->flags) &&
!test_bit(EC_FLAGS_STOPPED, &ec->flags);
}
static bool acpi_ec_flushed(struct acpi_ec *ec)
{
return ec->reference_count == 1;
}
/* --------------------------------------------------------------------------
* EC Registers
* -------------------------------------------------------------------------- */
static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
{
u8 x = inb(ec->command_addr);
ec_dbg_raw("EC_SC(R) = 0x%2.2x "
"SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d",
x,
!!(x & ACPI_EC_FLAG_SCI),
!!(x & ACPI_EC_FLAG_BURST),
!!(x & ACPI_EC_FLAG_CMD),
!!(x & ACPI_EC_FLAG_IBF),
!!(x & ACPI_EC_FLAG_OBF));
return x;
}
static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
{
u8 x = inb(ec->data_addr);
ec->curr->timestamp = jiffies;
ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x);
return x;
}
static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
{
ec_dbg_raw("EC_SC(W) = 0x%2.2x", command);
outb(command, ec->command_addr);
ec->curr->timestamp = jiffies;
}
static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
{
ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data);
outb(data, ec->data_addr);
ec->curr->timestamp = jiffies;
}
#ifdef DEBUG
static const char *acpi_ec_cmd_string(u8 cmd)
{
switch (cmd) {
case 0x80:
return "RD_EC";
case 0x81:
return "WR_EC";
case 0x82:
return "BE_EC";
case 0x83:
return "BD_EC";
case 0x84:
return "QR_EC";
}
return "UNKNOWN";
}
#else
#define acpi_ec_cmd_string(cmd) "UNDEF"
#endif
/* --------------------------------------------------------------------------
* GPE Registers
* -------------------------------------------------------------------------- */
static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec)
{
acpi_event_status gpe_status = 0;
(void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status);
return (gpe_status & ACPI_EVENT_FLAG_SET) ? true : false;
}
static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open)
{
if (open)
acpi_enable_gpe(NULL, ec->gpe);
else {
BUG_ON(ec->reference_count < 1);
acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
}
if (acpi_ec_is_gpe_raised(ec)) {
/*
* On some platforms, EN=1 writes cannot trigger GPE. So
* software need to manually trigger a pseudo GPE event on
* EN=1 writes.
*/
ec_dbg_raw("Polling quirk");
advance_transaction(ec);
}
}
static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close)
{
if (close)
acpi_disable_gpe(NULL, ec->gpe);
else {
BUG_ON(ec->reference_count < 1);
acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
}
}
static inline void acpi_ec_clear_gpe(struct acpi_ec *ec)
{
/*
* GPE STS is a W1C register, which means:
* 1. Software can clear it without worrying about clearing other
* GPEs' STS bits when the hardware sets them in parallel.
* 2. As long as software can ensure only clearing it when it is
* set, hardware won't set it in parallel.
* So software can clear GPE in any contexts.
* Warning: do not move the check into advance_transaction() as the
* EC commands will be sent without GPE raised.
*/
if (!acpi_ec_is_gpe_raised(ec))
return;
acpi_clear_gpe(NULL, ec->gpe);
}
/* --------------------------------------------------------------------------
* Transaction Management
* -------------------------------------------------------------------------- */
static void acpi_ec_submit_request(struct acpi_ec *ec)
{
ec->reference_count++;
if (ec->reference_count == 1)
acpi_ec_enable_gpe(ec, true);
}
static void acpi_ec_complete_request(struct acpi_ec *ec)
{
bool flushed = false;
ec->reference_count--;
if (ec->reference_count == 0)
acpi_ec_disable_gpe(ec, true);
flushed = acpi_ec_flushed(ec);
if (flushed)
wake_up(&ec->wait);
}
static void acpi_ec_set_storm(struct acpi_ec *ec, u8 flag)
{
if (!test_bit(flag, &ec->flags)) {
acpi_ec_disable_gpe(ec, false);
ec_dbg_drv("Polling enabled");
set_bit(flag, &ec->flags);
}
}
static void acpi_ec_clear_storm(struct acpi_ec *ec, u8 flag)
{
if (test_bit(flag, &ec->flags)) {
clear_bit(flag, &ec->flags);
acpi_ec_enable_gpe(ec, false);
ec_dbg_drv("Polling disabled");
}
}
/*
* acpi_ec_submit_flushable_request() - Increase the reference count unless
* the flush operation is not in
* progress
* @ec: the EC device
*
* This function must be used before taking a new action that should hold
* the reference count. If this function returns false, then the action
* must be discarded or it will prevent the flush operation from being
* completed.
*/
static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec)
{
if (!acpi_ec_started(ec))
return false;
acpi_ec_submit_request(ec);
return true;
}
static void acpi_ec_submit_query(struct acpi_ec *ec)
{
if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
ec_dbg_req("Event started");
schedule_work(&ec->work);
}
}
static void acpi_ec_complete_query(struct acpi_ec *ec)
{
if (ec->curr->command == ACPI_EC_COMMAND_QUERY) {
clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
ec_dbg_req("Event stopped");
}
}
static int ec_transaction_completed(struct acpi_ec *ec)
{
unsigned long flags;
int ret = 0;
spin_lock_irqsave(&ec->lock, flags);
if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE))
ret = 1;
spin_unlock_irqrestore(&ec->lock, flags);
return ret;
}
static void advance_transaction(struct acpi_ec *ec)
{
struct transaction *t;
u8 status;
bool wakeup = false;
ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK",
smp_processor_id());
/*
* By always clearing STS before handling all indications, we can
* ensure a hardware STS 0->1 change after this clearing can always
* trigger a GPE interrupt.
*/
acpi_ec_clear_gpe(ec);
status = acpi_ec_read_status(ec);
t = ec->curr;
if (!t)
goto err;
if (t->flags & ACPI_EC_COMMAND_POLL) {
if (t->wlen > t->wi) {
if ((status & ACPI_EC_FLAG_IBF) == 0)
acpi_ec_write_data(ec, t->wdata[t->wi++]);
else
goto err;
} else if (t->rlen > t->ri) {
if ((status & ACPI_EC_FLAG_OBF) == 1) {
t->rdata[t->ri++] = acpi_ec_read_data(ec);
if (t->rlen == t->ri) {
t->flags |= ACPI_EC_COMMAND_COMPLETE;
if (t->command == ACPI_EC_COMMAND_QUERY)
ec_dbg_req("Command(%s) hardware completion",
acpi_ec_cmd_string(t->command));
wakeup = true;
}
} else
goto err;
} else if (t->wlen == t->wi &&
(status & ACPI_EC_FLAG_IBF) == 0) {
t->flags |= ACPI_EC_COMMAND_COMPLETE;
wakeup = true;
}
goto out;
} else {
if (EC_FLAGS_QUERY_HANDSHAKE &&
!(status & ACPI_EC_FLAG_SCI) &&
(t->command == ACPI_EC_COMMAND_QUERY)) {
t->flags |= ACPI_EC_COMMAND_POLL;
acpi_ec_complete_query(ec);
t->rdata[t->ri++] = 0x00;
t->flags |= ACPI_EC_COMMAND_COMPLETE;
ec_dbg_req("Command(%s) software completion",
acpi_ec_cmd_string(t->command));
wakeup = true;
} else if ((status & ACPI_EC_FLAG_IBF) == 0) {
acpi_ec_write_cmd(ec, t->command);
t->flags |= ACPI_EC_COMMAND_POLL;
acpi_ec_complete_query(ec);
} else
goto err;
goto out;
}
err:
/*
* If SCI bit is set, then don't think it's a false IRQ
* otherwise will take a not handled IRQ as a false one.
*/
if (!(status & ACPI_EC_FLAG_SCI)) {
if (in_interrupt() && t) {
if (t->irq_count < ec_storm_threshold)
++t->irq_count;
/* Allow triggering on 0 threshold */
if (t->irq_count == ec_storm_threshold)
acpi_ec_set_storm(ec, EC_FLAGS_COMMAND_STORM);
}
}
out:
if (status & ACPI_EC_FLAG_SCI)
acpi_ec_submit_query(ec);
if (wakeup && in_interrupt())
wake_up(&ec->wait);
}
static void start_transaction(struct acpi_ec *ec)
{
ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
ec->curr->flags = 0;
ec->curr->timestamp = jiffies;
advance_transaction(ec);
}
static int ec_poll(struct acpi_ec *ec)
{
unsigned long flags;
int repeat = 5; /* number of command restarts */
while (repeat--) {
unsigned long delay = jiffies +
msecs_to_jiffies(ec_delay);
unsigned long usecs = ACPI_EC_UDELAY_POLL;
do {
/* don't sleep with disabled interrupts */
if (EC_FLAGS_MSI || irqs_disabled()) {
usecs = ACPI_EC_MSI_UDELAY;
udelay(usecs);
if (ec_transaction_completed(ec))
return 0;
} else {
if (wait_event_timeout(ec->wait,
ec_transaction_completed(ec),
usecs_to_jiffies(usecs)))
return 0;
}
spin_lock_irqsave(&ec->lock, flags);
if (time_after(jiffies,
ec->curr->timestamp +
usecs_to_jiffies(usecs)))
advance_transaction(ec);
spin_unlock_irqrestore(&ec->lock, flags);
} while (time_before(jiffies, delay));
pr_debug("controller reset, restart transaction\n");
spin_lock_irqsave(&ec->lock, flags);
start_transaction(ec);
spin_unlock_irqrestore(&ec->lock, flags);
}
return -ETIME;
}
static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
struct transaction *t)
{
unsigned long tmp;
int ret = 0;
if (EC_FLAGS_MSI)
udelay(ACPI_EC_MSI_UDELAY);
/* start transaction */
spin_lock_irqsave(&ec->lock, tmp);
/* Enable GPE for command processing (IBF=0/OBF=1) */
if (!acpi_ec_submit_flushable_request(ec)) {
ret = -EINVAL;
goto unlock;
}
ec_dbg_ref(ec, "Increase command");
/* following two actions should be kept atomic */
ec->curr = t;
ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command));
start_transaction(ec);
spin_unlock_irqrestore(&ec->lock, tmp);
ret = ec_poll(ec);
spin_lock_irqsave(&ec->lock, tmp);
if (t->irq_count == ec_storm_threshold)
acpi_ec_clear_storm(ec, EC_FLAGS_COMMAND_STORM);
ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command));
ec->curr = NULL;
/* Disable GPE for command processing (IBF=0/OBF=1) */
acpi_ec_complete_request(ec);
ec_dbg_ref(ec, "Decrease command");
unlock:
spin_unlock_irqrestore(&ec->lock, tmp);
return ret;
}
static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
{
int status;
u32 glk;
if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
return -EINVAL;
if (t->rdata)
memset(t->rdata, 0, t->rlen);
mutex_lock(&ec->mutex);
if (ec->global_lock) {
status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
if (ACPI_FAILURE(status)) {
status = -ENODEV;
goto unlock;
}
}
status = acpi_ec_transaction_unlocked(ec, t);
if (test_bit(EC_FLAGS_COMMAND_STORM, &ec->flags))
msleep(1);
if (ec->global_lock)
acpi_release_global_lock(glk);
unlock:
mutex_unlock(&ec->mutex);
return status;
}
static int acpi_ec_burst_enable(struct acpi_ec *ec)
{
u8 d;
struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
.wdata = NULL, .rdata = &d,
.wlen = 0, .rlen = 1};
return acpi_ec_transaction(ec, &t);
}
static int acpi_ec_burst_disable(struct acpi_ec *ec)
{
struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
.wdata = NULL, .rdata = NULL,
.wlen = 0, .rlen = 0};
return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
acpi_ec_transaction(ec, &t) : 0;
}
static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data)
{
int result;
u8 d;
struct transaction t = {.command = ACPI_EC_COMMAND_READ,
.wdata = &address, .rdata = &d,
.wlen = 1, .rlen = 1};
result = acpi_ec_transaction(ec, &t);
*data = d;
return result;
}
static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
{
u8 wdata[2] = { address, data };
struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
.wdata = wdata, .rdata = NULL,
.wlen = 2, .rlen = 0};
return acpi_ec_transaction(ec, &t);
}
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;
}
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,
u8 *rdata, unsigned rdata_len)
{
struct transaction t = {.command = command,
.wdata = wdata, .rdata = rdata,
.wlen = wdata_len, .rlen = rdata_len};
if (!first_ec)
return -ENODEV;
return acpi_ec_transaction(first_ec, &t);
}
EXPORT_SYMBOL(ec_transaction);
/* Get the handle to the EC device */
acpi_handle ec_get_handle(void)
{
if (!first_ec)
return NULL;
return first_ec->handle;
}
EXPORT_SYMBOL(ec_get_handle);
/*
* Process _Q events that might have accumulated in the EC.
* Run with locked ec mutex.
*/
static void acpi_ec_clear(struct acpi_ec *ec)
{
int i, status;
u8 value = 0;
for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) {
status = acpi_ec_query(ec, &value);
if (status || !value)
break;
}
if (unlikely(i == ACPI_EC_CLEAR_MAX))
pr_warn("Warning: Maximum of %d stale EC events cleared\n", i);
else
pr_info("%d stale EC events cleared\n", i);
}
static void acpi_ec_start(struct acpi_ec *ec, bool resuming)
{
unsigned long flags;
spin_lock_irqsave(&ec->lock, flags);
if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) {
ec_dbg_drv("Starting EC");
/* Enable GPE for event processing (SCI_EVT=1) */
if (!resuming) {
acpi_ec_submit_request(ec);
ec_dbg_ref(ec, "Increase driver");
}
ec_log_drv("EC started");
}
spin_unlock_irqrestore(&ec->lock, flags);
}
static bool acpi_ec_stopped(struct acpi_ec *ec)
{
unsigned long flags;
bool flushed;
spin_lock_irqsave(&ec->lock, flags);
flushed = acpi_ec_flushed(ec);
spin_unlock_irqrestore(&ec->lock, flags);
return flushed;
}
static void acpi_ec_stop(struct acpi_ec *ec, bool suspending)
{
unsigned long flags;
spin_lock_irqsave(&ec->lock, flags);
if (acpi_ec_started(ec)) {
ec_dbg_drv("Stopping EC");
set_bit(EC_FLAGS_STOPPED, &ec->flags);
spin_unlock_irqrestore(&ec->lock, flags);
wait_event(ec->wait, acpi_ec_stopped(ec));
spin_lock_irqsave(&ec->lock, flags);
/* Disable GPE for event processing (SCI_EVT=1) */
if (!suspending) {
acpi_ec_complete_request(ec);
ec_dbg_ref(ec, "Decrease driver");
}
clear_bit(EC_FLAGS_STARTED, &ec->flags);
clear_bit(EC_FLAGS_STOPPED, &ec->flags);
ec_log_drv("EC stopped");
}
spin_unlock_irqrestore(&ec->lock, flags);
}
void acpi_ec_block_transactions(void)
{
struct acpi_ec *ec = first_ec;
if (!ec)
return;
mutex_lock(&ec->mutex);
/* Prevent transactions from being carried out */
acpi_ec_stop(ec, true);
mutex_unlock(&ec->mutex);
}
void acpi_ec_unblock_transactions(void)
{
struct acpi_ec *ec = first_ec;
if (!ec)
return;
/* Allow transactions to be carried out again */
acpi_ec_start(ec, true);
if (EC_FLAGS_CLEAR_ON_RESUME)
acpi_ec_clear(ec);
}
void acpi_ec_unblock_transactions_early(void)
{
/*
* Allow transactions to happen again (this function is called from
* atomic context during wakeup, so we don't need to acquire the mutex).
*/
if (first_ec)
acpi_ec_start(first_ec, true);
}
/* --------------------------------------------------------------------------
Event Management
-------------------------------------------------------------------------- */
static struct acpi_ec_query_handler *
acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler)
{
if (handler)
kref_get(&handler->kref);
return handler;
}
static void acpi_ec_query_handler_release(struct kref *kref)
{
struct acpi_ec_query_handler *handler =
container_of(kref, struct acpi_ec_query_handler, kref);
kfree(handler);
}
static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler)
{
kref_put(&handler->kref, acpi_ec_query_handler_release);
}
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->mutex);
kref_init(&handler->kref);
list_add(&handler->node, &ec->list);
mutex_unlock(&ec->mutex);
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;
LIST_HEAD(free_list);
mutex_lock(&ec->mutex);
list_for_each_entry_safe(handler, tmp, &ec->list, node) {
if (query_bit == handler->query_bit) {
list_del_init(&handler->node);
list_add(&handler->node, &free_list);
}
}
mutex_unlock(&ec->mutex);
list_for_each_entry(handler, &free_list, node)
acpi_ec_put_query_handler(handler);
}
EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
static void acpi_ec_run(void *cxt)
{
struct acpi_ec_query_handler *handler = cxt;
if (!handler)
return;
ec_dbg_evt("Query(0x%02x) started", handler->query_bit);
if (handler->func)
handler->func(handler->data);
else if (handler->handle)
acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit);
acpi_ec_put_query_handler(handler);
}
static int acpi_ec_query(struct acpi_ec *ec, u8 *data)
{
u8 value = 0;
int result;
acpi_status status;
struct acpi_ec_query_handler *handler;
struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
.wdata = NULL, .rdata = &value,
.wlen = 0, .rlen = 1};
/*
* 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).
*/
result = acpi_ec_transaction(ec, &t);
if (result)
return result;
if (data)
*data = value;
if (!value)
return -ENODATA;
mutex_lock(&ec->mutex);
list_for_each_entry(handler, &ec->list, node) {
if (value == handler->query_bit) {
/* have custom handler for this bit */
handler = acpi_ec_get_query_handler(handler);
ec_dbg_evt("Query(0x%02x) scheduled",
handler->query_bit);
status = acpi_os_execute((handler->func) ?
OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
acpi_ec_run, handler);
if (ACPI_FAILURE(status))
result = -EBUSY;
break;
}
}
mutex_unlock(&ec->mutex);
return result;
}
static void acpi_ec_gpe_poller(struct work_struct *work)
{
struct acpi_ec *ec = container_of(work, struct acpi_ec, work);
acpi_ec_query(ec, NULL);
}
static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
u32 gpe_number, void *data)
{
unsigned long flags;
struct acpi_ec *ec = data;
spin_lock_irqsave(&ec->lock, flags);
advance_transaction(ec);
spin_unlock_irqrestore(&ec->lock, flags);
return ACPI_INTERRUPT_HANDLED;
}
/* --------------------------------------------------------------------------
* Address Space Management
* -------------------------------------------------------------------------- */
static acpi_status
acpi_ec_space_handler(u32 function, acpi_physical_address address,
u32 bits, u64 *value64,
void *handler_context, void *region_context)
{
struct acpi_ec *ec = handler_context;
int result = 0, i, bytes = bits / 8;
u8 *value = (u8 *)value64;
if ((address > 0xFF) || !value || !handler_context)
return AE_BAD_PARAMETER;
if (function != ACPI_READ && function != ACPI_WRITE)
return AE_BAD_PARAMETER;
if (EC_FLAGS_MSI || bits > 8)
acpi_ec_burst_enable(ec);
for (i = 0; i < bytes; ++i, ++address, ++value)
result = (function == ACPI_READ) ?
acpi_ec_read(ec, address, value) :
acpi_ec_write(ec, address, *value);
if (EC_FLAGS_MSI || bits > 8)
acpi_ec_burst_disable(ec);
switch (result) {
case -EINVAL:
return AE_BAD_PARAMETER;
case -ENODEV:
return AE_NOT_FOUND;
case -ETIME:
return AE_TIME;
default:
return AE_OK;
}
}
/* --------------------------------------------------------------------------
* 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->mutex);
init_waitqueue_head(&ec->wait);
INIT_LIST_HEAD(&ec->list);
spin_lock_init(&ec->lock);
INIT_WORK(&ec->work, acpi_ec_gpe_poller);
return ec;
}
static acpi_status
acpi_ec_register_query_methods(acpi_handle handle, u32 level,
void *context, void **return_value)
{
char node_name[5];
struct acpi_buffer buffer = { sizeof(node_name), node_name };
struct acpi_ec *ec = context;
int value = 0;
acpi_status status;
status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
if (ACPI_SUCCESS(status) && sscanf(node_name, "_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;
unsigned long long tmp = 0;
struct acpi_ec *ec = context;
/* clear addr values, ec_parse_io_ports depend on it */
ec->command_addr = ec->data_addr = 0;
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, &tmp);
if (ACPI_FAILURE(status))
return status;
ec->gpe = tmp;
/* Use the global lock for all EC transactions? */
tmp = 0;
acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
ec->global_lock = tmp;
ec->handle = handle;
return AE_CTRL_TERMINATE;
}
static int ec_install_handlers(struct acpi_ec *ec)
{
acpi_status status;
if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
return 0;
status = acpi_install_gpe_raw_handler(NULL, ec->gpe,
ACPI_GPE_EDGE_TRIGGERED,
&acpi_ec_gpe_handler, ec);
if (ACPI_FAILURE(status))
return -ENODEV;
acpi_ec_start(ec, false);
status = acpi_install_address_space_handler(ec->handle,
ACPI_ADR_SPACE_EC,
&acpi_ec_space_handler,
NULL, ec);
if (ACPI_FAILURE(status)) {
if (status == AE_NOT_FOUND) {
/*
* Maybe OS fails in evaluating the _REG object.
* The AE_NOT_FOUND error will be ignored and OS
* continue to initialize EC.
*/
pr_err("Fail in evaluating the _REG object"
" of EC device. Broken bios is suspected.\n");
} else {
acpi_ec_stop(ec, false);
acpi_remove_gpe_handler(NULL, ec->gpe,
&acpi_ec_gpe_handler);
return -ENODEV;
}
}
set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
return 0;
}
static void ec_remove_handlers(struct acpi_ec *ec)
{
if (!test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
return;
acpi_ec_stop(ec, false);
if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
pr_err("failed to remove space handler\n");
if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
&acpi_ec_gpe_handler)))
pr_err("failed to remove gpe handler\n");
clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
}
static int acpi_ec_add(struct acpi_device *device)
{
struct acpi_ec *ec = NULL;
int ret;
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;
}
/* Find and register all query methods */
acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
acpi_ec_register_query_methods, NULL, ec, NULL);
if (!first_ec)
first_ec = ec;
device->driver_data = ec;
ret = !!request_region(ec->data_addr, 1, "EC data");
WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
ret = !!request_region(ec->command_addr, 1, "EC cmd");
WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
pr_info("GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
ec->gpe, ec->command_addr, ec->data_addr);
ret = ec_install_handlers(ec);
/* EC is fully operational, allow queries */
clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
/* Clear stale _Q events if hardware might require that */
if (EC_FLAGS_CLEAR_ON_RESUME)
acpi_ec_clear(ec);
return ret;
}
static int acpi_ec_remove(struct acpi_device *device)
{
struct acpi_ec *ec;
struct acpi_ec_query_handler *handler, *tmp;
if (!device)
return -EINVAL;
ec = acpi_driver_data(device);
ec_remove_handlers(ec);
mutex_lock(&ec->mutex);
list_for_each_entry_safe(handler, tmp, &ec->list, node) {
list_del(&handler->node);
kfree(handler);
}
mutex_unlock(&ec->mutex);
release_region(ec->data_addr, 1);
release_region(ec->command_addr, 1);
device->driver_data = 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;
}
int __init acpi_boot_ec_enable(void)
{
if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
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},
};
/* Some BIOS do not survive early DSDT scan, skip it */
static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
{
EC_FLAGS_SKIP_DSDT_SCAN = 1;
return 0;
}
/* ASUStek often supplies us with broken ECDT, validate it */
static int ec_validate_ecdt(const struct dmi_system_id *id)
{
EC_FLAGS_VALIDATE_ECDT = 1;
return 0;
}
/* MSI EC needs special treatment, enable it */
static int ec_flag_msi(const struct dmi_system_id *id)
{
pr_debug("Detected MSI hardware, enabling workarounds.\n");
EC_FLAGS_MSI = 1;
EC_FLAGS_VALIDATE_ECDT = 1;
return 0;
}
/*
* Clevo M720 notebook actually works ok with IRQ mode, if we lifted
* the GPE storm threshold back to 20
*/
static int ec_enlarge_storm_threshold(const struct dmi_system_id *id)
{
pr_debug("Setting the EC GPE storm threshold to 20\n");
ec_storm_threshold = 20;
return 0;
}
/*
* Acer EC firmware refuses to respond QR_EC when SCI_EVT is not set, for
* which case, we complete the QR_EC without issuing it to the firmware.
* https://bugzilla.kernel.org/show_bug.cgi?id=86211
*/
static int ec_flag_query_handshake(const struct dmi_system_id *id)
{
pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n");
EC_FLAGS_QUERY_HANDSHAKE = 1;
return 0;
}
/*
* On some hardware it is necessary to clear events accumulated by the EC during
* sleep. These ECs stop reporting GPEs until they are manually polled, if too
* many events are accumulated. (e.g. Samsung Series 5/9 notebooks)
*
* https://bugzilla.kernel.org/show_bug.cgi?id=44161
*
* Ideally, the EC should also be instructed NOT to accumulate events during
* sleep (which Windows seems to do somehow), but the interface to control this
* behaviour is not known at this time.
*
* Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx,
* however it is very likely that other Samsung models are affected.
*
* On systems which don't accumulate _Q events during sleep, this extra check
* should be harmless.
*/
static int ec_clear_on_resume(const struct dmi_system_id *id)
{
pr_debug("Detected system needing EC poll on resume.\n");
EC_FLAGS_CLEAR_ON_RESUME = 1;
return 0;
}
static struct dmi_system_id ec_dmi_table[] __initdata = {
{
ec_skip_dsdt_scan, "Compal JFL92", {
DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
{
ec_flag_msi, "MSI hardware", {
DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
{
ec_flag_msi, "MSI hardware", {
DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
{
ec_flag_msi, "MSI hardware", {
DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
{
ec_flag_msi, "MSI hardware", {
DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-STAR")}, NULL},
{
ec_flag_msi, "Quanta hardware", {
DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
DMI_MATCH(DMI_PRODUCT_NAME, "TW8/SW8/DW8"),}, NULL},
{
ec_flag_msi, "Quanta hardware", {
DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
DMI_MATCH(DMI_PRODUCT_NAME, "TW9/SW9"),}, NULL},
{
ec_flag_msi, "Clevo W350etq", {
DMI_MATCH(DMI_SYS_VENDOR, "CLEVO CO."),
DMI_MATCH(DMI_PRODUCT_NAME, "W35_37ET"),}, NULL},
{
ec_validate_ecdt, "ASUS hardware", {
DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
{
ec_validate_ecdt, "ASUS hardware", {
DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL},
{
ec_enlarge_storm_threshold, "CLEVO hardware", {
DMI_MATCH(DMI_SYS_VENDOR, "CLEVO Co."),
DMI_MATCH(DMI_PRODUCT_NAME, "M720T/M730T"),}, NULL},
{
ec_skip_dsdt_scan, "HP Folio 13", {
DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13"),}, NULL},
{
ec_validate_ecdt, "ASUS hardware", {
DMI_MATCH(DMI_SYS_VENDOR, "ASUSTek Computer Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),}, NULL},
{
ec_clear_on_resume, "Samsung hardware", {
DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL},
{
ec_flag_query_handshake, "Acer hardware", {
DMI_MATCH(DMI_SYS_VENDOR, "Acer"), }, NULL},
{},
};
int __init acpi_ec_ecdt_probe(void)
{
acpi_status status;
struct acpi_ec *saved_ec = NULL;
struct acpi_table_ecdt *ecdt_ptr;
boot_ec = make_acpi_ec();
if (!boot_ec)
return -ENOMEM;
/*
* Generate a boot ec context
*/
dmi_check_system(ec_dmi_table);
status = acpi_get_table(ACPI_SIG_ECDT, 1,
(struct acpi_table_header **)&ecdt_ptr);
if (ACPI_SUCCESS(status)) {
pr_info("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;
boot_ec->gpe = ecdt_ptr->gpe;
boot_ec->handle = ACPI_ROOT_OBJECT;
acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id,
&boot_ec->handle);
/* Don't trust ECDT, which comes from ASUSTek */
if (!EC_FLAGS_VALIDATE_ECDT)
goto install;
saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
if (!saved_ec)
return -ENOMEM;
/* fall through */
}
if (EC_FLAGS_SKIP_DSDT_SCAN) {
kfree(saved_ec);
return -ENODEV;
}
/* This workaround is needed only on some broken machines,
* which require early EC, but fail to provide ECDT */
pr_debug("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;
if (saved_ec) {
/* try to find good ECDT from ASUSTek */
if (saved_ec->command_addr != boot_ec->command_addr ||
saved_ec->data_addr != boot_ec->data_addr ||
saved_ec->gpe != boot_ec->gpe ||
saved_ec->handle != boot_ec->handle)
pr_info("ASUSTek keeps feeding us with broken "
"ECDT tables, which are very hard to workaround. "
"Trying to use DSDT EC info instead. Please send "
"output of acpidump to linux-acpi@vger.kernel.org\n");
kfree(saved_ec);
saved_ec = NULL;
} else {
/* 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 (!dmi_name_in_vendors("ASUS") ||
!acpi_has_method(boot_ec->handle, "_INI"))
return -ENODEV;
}
install:
if (!ec_install_handlers(boot_ec)) {
first_ec = boot_ec;
return 0;
}
error:
kfree(boot_ec);
kfree(saved_ec);
boot_ec = NULL;
return -ENODEV;
}
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,
},
};
int __init acpi_ec_init(void)
{
int result = 0;
/* Now register the driver for the EC */
result = acpi_bus_register_driver(&acpi_ec_driver);
if (result < 0)
return -ENODEV;
return result;
}
/* EC driver currently not unloadable */
#if 0
static void __exit acpi_ec_exit(void)
{
acpi_bus_unregister_driver(&acpi_ec_driver);
}
#endif /* 0 */
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