redonkable/remarkable-linux
redonkable/remarkable-linux
1
0
Fork 0
Code Releases Activity
remarkable-linux/drivers/acpi/ec.c
Lv Zheng c3a696b6e8 ACPI / EC: Use busy polling mode when GPE is not enabled 
When GPE is not enabled, it is not efficient to use the wait polling mode
as it introduces an unexpected scheduler delay.
So before the GPE handler is installed, this patch uses busy polling mode
for all EC(s) and the logic can be applied to non boot EC(s) during the
suspend/resume process.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=191561
Tested-by: Jakobus Schurz <jakobus.schurz@gmail.com>
Tested-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-01-30 12:12:52 +01:00

1953 lines
52 KiB
C
Raw Blame History

/*
* 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.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
/* 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 */
/*
* The SCI_EVT clearing timing is not defined by the ACPI specification.
* This leads to lots of practical timing issues for the host EC driver.
* The following variations are defined (from the target EC firmware's
* perspective):
* STATUS: After indicating SCI_EVT edge triggered IRQ to the host, the
* target can clear SCI_EVT at any time so long as the host can see
* the indication by reading the status register (EC_SC). So the
* host should re-check SCI_EVT after the first time the SCI_EVT
* indication is seen, which is the same time the query request
* (QR_EC) is written to the command register (EC_CMD). SCI_EVT set
* at any later time could indicate another event. Normally such
* kind of EC firmware has implemented an event queue and will
* return 0x00 to indicate "no outstanding event".
* QUERY: After seeing the query request (QR_EC) written to the command
* register (EC_CMD) by the host and having prepared the responding
* event value in the data register (EC_DATA), the target can safely
* clear SCI_EVT because the target can confirm that the current
* event is being handled by the host. The host then should check
* SCI_EVT right after reading the event response from the data
* register (EC_DATA).
* EVENT: After seeing the event response read from the data register
* (EC_DATA) by the host, the target can clear SCI_EVT. As the
* target requires time to notice the change in the data register
* (EC_DATA), the host may be required to wait additional guarding
* time before checking the SCI_EVT again. Such guarding may not be
* necessary if the host is notified via another IRQ.
*/
#define ACPI_EC_EVT_TIMING_STATUS 0x00
#define ACPI_EC_EVT_TIMING_QUERY 0x01
#define ACPI_EC_EVT_TIMING_EVENT 0x02
/* 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_UDELAY_POLL 550 /* Wait 1ms for EC transaction polling */
#define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query
* when trying to clear the EC */
#define ACPI_EC_MAX_QUERIES 16 /* Maximum number of parallel queries */
enum {
EC_FLAGS_QUERY_ENABLED, /* Query is enabled */
EC_FLAGS_QUERY_PENDING, /* Query is pending */
EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */
EC_FLAGS_GPE_HANDLER_INSTALLED, /* GPE handler installed */
EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */
EC_FLAGS_EVT_HANDLER_INSTALLED, /* _Qxx handlers 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");
static unsigned int ec_max_queries __read_mostly = ACPI_EC_MAX_QUERIES;
module_param(ec_max_queries, uint, 0644);
MODULE_PARM_DESC(ec_max_queries, "Maximum parallel _Qxx evaluations");
static bool ec_busy_polling __read_mostly;
module_param(ec_busy_polling, bool, 0644);
MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction");
static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL;
module_param(ec_polling_guard, uint, 0644);
MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes");
static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY;
/*
* 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");
static bool ec_freeze_events __read_mostly = true;
module_param(ec_freeze_events, bool, 0644);
MODULE_PARM_DESC(ec_freeze_events, "Disabling event handling during suspend/resume");
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;
};
struct acpi_ec_query {
struct transaction transaction;
struct work_struct work;
struct acpi_ec_query_handler *handler;
};
static int acpi_ec_query(struct acpi_ec *ec, u8 *data);
static void advance_transaction(struct acpi_ec *ec);
static void acpi_ec_event_handler(struct work_struct *work);
static void acpi_ec_event_processor(struct work_struct *work);
struct acpi_ec *boot_ec, *first_ec;
EXPORT_SYMBOL(first_ec);
static bool boot_ec_is_ecdt = false;
static struct workqueue_struct *ec_query_wq;
static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */
static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */
/* --------------------------------------------------------------------------
* 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_event_enabled(struct acpi_ec *ec)
{
/*
* There is an OSPM early stage logic. During the early stages
* (boot/resume), OSPMs shouldn't enable the event handling, only
* the EC transactions are allowed to be performed.
*/
if (!test_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
return false;
/*
* However, disabling the event handling is experimental for late
* stage (suspend), and is controlled by the boot parameter of
* "ec_freeze_events":
* 1. true: The EC event handling is disabled before entering
* the noirq stage.
* 2. false: The EC event handling is automatically disabled as
* soon as the EC driver is stopped.
*/
if (ec_freeze_events)
return acpi_ec_started(ec);
else
return test_bit(EC_FLAGS_STARTED, &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->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->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->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_STATUS_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 (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) &&
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 (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) &&
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 (acpi_ec_event_enabled(ec) &&
!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
ec_dbg_evt("Command(%s) submitted/blocked",
acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
ec->nr_pending_queries++;
schedule_work(&ec->work);
}
}
static void acpi_ec_complete_query(struct acpi_ec *ec)
{
if (test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
ec_dbg_evt("Command(%s) unblocked",
acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
}
}
static inline void __acpi_ec_enable_event(struct acpi_ec *ec)
{
if (!test_and_set_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
ec_log_drv("event unblocked");
if (!test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
advance_transaction(ec);
}
static inline void __acpi_ec_disable_event(struct acpi_ec *ec)
{
if (test_and_clear_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
ec_log_drv("event blocked");
}
static void acpi_ec_enable_event(struct acpi_ec *ec)
{
unsigned long flags;
spin_lock_irqsave(&ec->lock, flags);
if (acpi_ec_started(ec))
__acpi_ec_enable_event(ec);
spin_unlock_irqrestore(&ec->lock, flags);
}
#ifdef CONFIG_PM_SLEEP
static bool acpi_ec_query_flushed(struct acpi_ec *ec)
{
bool flushed;
unsigned long flags;
spin_lock_irqsave(&ec->lock, flags);
flushed = !ec->nr_pending_queries;
spin_unlock_irqrestore(&ec->lock, flags);
return flushed;
}
static void __acpi_ec_flush_event(struct acpi_ec *ec)
{
/*
* When ec_freeze_events is true, we need to flush events in
* the proper position before entering the noirq stage.
*/
wait_event(ec->wait, acpi_ec_query_flushed(ec));
if (ec_query_wq)
flush_workqueue(ec_query_wq);
}
static void acpi_ec_disable_event(struct acpi_ec *ec)
{
unsigned long flags;
spin_lock_irqsave(&ec->lock, flags);
__acpi_ec_disable_event(ec);
spin_unlock_irqrestore(&ec->lock, flags);
__acpi_ec_flush_event(ec);
}
#endif /* CONFIG_PM_SLEEP */
static bool acpi_ec_guard_event(struct acpi_ec *ec)
{
bool guarded = true;
unsigned long flags;
spin_lock_irqsave(&ec->lock, flags);
/*
* If firmware SCI_EVT clearing timing is "event", we actually
* don't know when the SCI_EVT will be cleared by firmware after
* evaluating _Qxx, so we need to re-check SCI_EVT after waiting an
* acceptable period.
*
* The guarding period begins when EC_FLAGS_QUERY_PENDING is
* flagged, which means SCI_EVT check has just been performed.
* But if the current transaction is ACPI_EC_COMMAND_QUERY, the
* guarding should have already been performed (via
* EC_FLAGS_QUERY_GUARDING) and should not be applied so that the
* ACPI_EC_COMMAND_QUERY transaction can be transitioned into
* ACPI_EC_COMMAND_POLL state immediately.
*/
if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS ||
ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY ||
!test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) ||
(ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY))
guarded = false;
spin_unlock_irqrestore(&ec->lock, flags);
return guarded;
}
static int ec_transaction_polled(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_POLL))
ret = 1;
spin_unlock_irqrestore(&ec->lock, flags);
return ret;
}
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 inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag)
{
ec->curr->flags |= flag;
if (ec->curr->command == ACPI_EC_COMMAND_QUERY) {
if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS &&
flag == ACPI_EC_COMMAND_POLL)
acpi_ec_complete_query(ec);
if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY &&
flag == ACPI_EC_COMMAND_COMPLETE)
acpi_ec_complete_query(ec);
if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT &&
flag == ACPI_EC_COMMAND_COMPLETE)
set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags);
}
}
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;
/*
* Another IRQ or a guarded polling mode advancement is detected,
* the next QR_EC submission is then allowed.
*/
if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) {
if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT &&
(!ec->nr_pending_queries ||
test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) {
clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags);
acpi_ec_complete_query(ec);
}
}
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) {
ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
if (t->command == ACPI_EC_COMMAND_QUERY)
ec_dbg_evt("Command(%s) completed by hardware",
acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
wakeup = true;
}
} else
goto err;
} else if (t->wlen == t->wi &&
(status & ACPI_EC_FLAG_IBF) == 0) {
ec_transaction_transition(ec, 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)) {
ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL);
t->rdata[t->ri++] = 0x00;
ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
ec_dbg_evt("Command(%s) completed by software",
acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
wakeup = true;
} else if ((status & ACPI_EC_FLAG_IBF) == 0) {
acpi_ec_write_cmd(ec, t->command);
ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL);
} 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;
}
static int ec_guard(struct acpi_ec *ec)
{
unsigned long guard = usecs_to_jiffies(ec->polling_guard);
unsigned long timeout = ec->timestamp + guard;
/* Ensure guarding period before polling EC status */
do {
if (ec->busy_polling) {
/* Perform busy polling */
if (ec_transaction_completed(ec))
return 0;
udelay(jiffies_to_usecs(guard));
} else {
/*
* Perform wait polling
* 1. Wait the transaction to be completed by the
* GPE handler after the transaction enters
* ACPI_EC_COMMAND_POLL state.
* 2. A special guarding logic is also required
* for event clearing mode "event" before the
* transaction enters ACPI_EC_COMMAND_POLL
* state.
*/
if (!ec_transaction_polled(ec) &&
!acpi_ec_guard_event(ec))
break;
if (wait_event_timeout(ec->wait,
ec_transaction_completed(ec),
guard))
return 0;
}
} while (time_before(jiffies, timeout));
return -ETIME;
}
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);
do {
if (!ec_guard(ec))
return 0;
spin_lock_irqsave(&ec->lock, flags);
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;
/* 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 (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);
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");
} else if (!ec_freeze_events)
__acpi_ec_disable_event(ec);
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);
}
static void acpi_ec_enter_noirq(struct acpi_ec *ec)
{
unsigned long flags;
spin_lock_irqsave(&ec->lock, flags);
ec->busy_polling = true;
ec->polling_guard = 0;
ec_log_drv("interrupt blocked");
spin_unlock_irqrestore(&ec->lock, flags);
}
static void acpi_ec_leave_noirq(struct acpi_ec *ec)
{
unsigned long flags;
spin_lock_irqsave(&ec->lock, flags);
ec->busy_polling = ec_busy_polling;
ec->polling_guard = ec_polling_guard;
ec_log_drv("interrupt unblocked");
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)
{
/*
* 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 struct acpi_ec_query_handler *
acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value)
{
struct acpi_ec_query_handler *handler;
bool found = false;
mutex_lock(&ec->mutex);
list_for_each_entry(handler, &ec->list, node) {
if (value == handler->query_bit) {
found = true;
break;
}
}
mutex_unlock(&ec->mutex);
return found ? acpi_ec_get_query_handler(handler) : NULL;
}
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);
static void acpi_ec_remove_query_handlers(struct acpi_ec *ec,
bool remove_all, 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 (remove_all || query_bit == handler->query_bit) {
list_del_init(&handler->node);
list_add(&handler->node, &free_list);
}
}
mutex_unlock(&ec->mutex);
list_for_each_entry_safe(handler, tmp, &free_list, node)
acpi_ec_put_query_handler(handler);
}
void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
{
acpi_ec_remove_query_handlers(ec, false, query_bit);
}
EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
static struct acpi_ec_query *acpi_ec_create_query(u8 *pval)
{
struct acpi_ec_query *q;
struct transaction *t;
q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL);
if (!q)
return NULL;
INIT_WORK(&q->work, acpi_ec_event_processor);
t = &q->transaction;
t->command = ACPI_EC_COMMAND_QUERY;
t->rdata = pval;
t->rlen = 1;
return q;
}
static void acpi_ec_delete_query(struct acpi_ec_query *q)
{
if (q) {
if (q->handler)
acpi_ec_put_query_handler(q->handler);
kfree(q);
}
}
static void acpi_ec_event_processor(struct work_struct *work)
{
struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work);
struct acpi_ec_query_handler *handler = q->handler;
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_delete_query(q);
}
static int acpi_ec_query(struct acpi_ec *ec, u8 *data)
{
u8 value = 0;
int result;
struct acpi_ec_query *q;
q = acpi_ec_create_query(&value);
if (!q)
return -ENOMEM;
/*
* 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, &q->transaction);
if (!value)
result = -ENODATA;
if (result)
goto err_exit;
q->handler = acpi_ec_get_query_handler_by_value(ec, value);
if (!q->handler) {
result = -ENODATA;
goto err_exit;
}
/*
* It is reported that _Qxx are evaluated in a parallel way on
* Windows:
* https://bugzilla.kernel.org/show_bug.cgi?id=94411
*
* Put this log entry before schedule_work() in order to make
* it appearing before any other log entries occurred during the
* work queue execution.
*/
ec_dbg_evt("Query(0x%02x) scheduled", value);
if (!queue_work(ec_query_wq, &q->work)) {
ec_dbg_evt("Query(0x%02x) overlapped", value);
result = -EBUSY;
}
err_exit:
if (result)
acpi_ec_delete_query(q);
if (data)
*data = value;
return result;
}
static void acpi_ec_check_event(struct acpi_ec *ec)
{
unsigned long flags;
if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) {
if (ec_guard(ec)) {
spin_lock_irqsave(&ec->lock, flags);
/*
* Take care of the SCI_EVT unless no one else is
* taking care of it.
*/
if (!ec->curr)
advance_transaction(ec);
spin_unlock_irqrestore(&ec->lock, flags);
}
}
}
static void acpi_ec_event_handler(struct work_struct *work)
{
unsigned long flags;
struct acpi_ec *ec = container_of(work, struct acpi_ec, work);
ec_dbg_evt("Event started");
spin_lock_irqsave(&ec->lock, flags);
while (ec->nr_pending_queries) {
spin_unlock_irqrestore(&ec->lock, flags);
(void)acpi_ec_query(ec, NULL);
spin_lock_irqsave(&ec->lock, flags);
ec->nr_pending_queries--;
/*
* Before exit, make sure that this work item can be
* scheduled again. There might be QR_EC failures, leaving
* EC_FLAGS_QUERY_PENDING uncleared and preventing this work
* item from being scheduled again.
*/
if (!ec->nr_pending_queries) {
if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS ||
ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY)
acpi_ec_complete_query(ec);
}
}
spin_unlock_irqrestore(&ec->lock, flags);
ec_dbg_evt("Event stopped");
acpi_ec_check_event(ec);
}
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->busy_polling || 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->busy_polling || 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 void acpi_ec_free(struct acpi_ec *ec)
{
if (first_ec == ec)
first_ec = NULL;
if (boot_ec == ec)
boot_ec = NULL;
kfree(ec);
}
static struct acpi_ec *acpi_ec_alloc(void)
{
struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
if (!ec)
return NULL;
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_event_handler);
ec->timestamp = jiffies;
ec->busy_polling = true;
ec->polling_guard = 0;
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;
}
/*
* Note: This function returns an error code only when the address space
* handler is not installed, which means "not able to handle
* transactions".
*/
static int ec_install_handlers(struct acpi_ec *ec, bool handle_events)
{
acpi_status status;
acpi_ec_start(ec, false);
if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) {
acpi_ec_enter_noirq(ec);
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);
return -ENODEV;
}
}
set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags);
}
if (!handle_events)
return 0;
if (!test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) {
/* Find and register all query methods */
acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
acpi_ec_register_query_methods,
NULL, ec, NULL);
set_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags);
}
if (!test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) {
status = acpi_install_gpe_raw_handler(NULL, ec->gpe,
ACPI_GPE_EDGE_TRIGGERED,
&acpi_ec_gpe_handler, ec);
/* This is not fatal as we can poll EC events */
if (ACPI_SUCCESS(status)) {
set_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags);
acpi_ec_leave_noirq(ec);
if (test_bit(EC_FLAGS_STARTED, &ec->flags) &&
ec->reference_count >= 1)
acpi_ec_enable_gpe(ec, true);
/* EC is fully operational, allow queries */
acpi_ec_enable_event(ec);
}
}
return 0;
}
static void ec_remove_handlers(struct acpi_ec *ec)
{
if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) {
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");
clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags);
}
/*
* Stops handling the EC transactions after removing the operation
* region handler. This is required because _REG(DISCONNECT)
* invoked during the removal can result in new EC transactions.
*
* Flushes the EC requests and thus disables the GPE before
* removing the GPE handler. This is required by the current ACPICA
* GPE core. ACPICA GPE core will automatically disable a GPE when
* it is indicated but there is no way to handle it. So the drivers
* must disable the GPEs prior to removing the GPE handlers.
*/
acpi_ec_stop(ec, false);
if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) {
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_GPE_HANDLER_INSTALLED, &ec->flags);
}
if (test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) {
acpi_ec_remove_query_handlers(ec, true, 0);
clear_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags);
}
}
static int acpi_ec_setup(struct acpi_ec *ec, bool handle_events)
{
int ret;
ret = ec_install_handlers(ec, handle_events);
if (ret)
return ret;
/* First EC capable of handling transactions */
if (!first_ec) {
first_ec = ec;
acpi_handle_info(first_ec->handle, "Used as first EC\n");
}
acpi_handle_info(ec->handle,
"GPE=0x%lx, EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n",
ec->gpe, ec->command_addr, ec->data_addr);
return ret;
}
static int acpi_config_boot_ec(struct acpi_ec *ec, acpi_handle handle,
bool handle_events, bool is_ecdt)
{
int ret;
/*
* Changing the ACPI handle results in a re-configuration of the
* boot EC. And if it happens after the namespace initialization,
* it causes _REG evaluations.
*/
if (boot_ec && boot_ec->handle != handle)
ec_remove_handlers(boot_ec);
/* Unset old boot EC */
if (boot_ec != ec)
acpi_ec_free(boot_ec);
/*
* ECDT device creation is split into acpi_ec_ecdt_probe() and
* acpi_ec_ecdt_start(). This function takes care of completing the
* ECDT parsing logic as the handle update should be performed
* between the installation/uninstallation of the handlers.
*/
if (ec->handle != handle)
ec->handle = handle;
ret = acpi_ec_setup(ec, handle_events);
if (ret)
return ret;
/* Set new boot EC */
if (!boot_ec) {
boot_ec = ec;
boot_ec_is_ecdt = is_ecdt;
}
acpi_handle_info(boot_ec->handle,
"Used as boot %s EC to handle transactions%s\n",
is_ecdt ? "ECDT" : "DSDT",
handle_events ? " and events" : "");
return ret;
}
static bool acpi_ec_ecdt_get_handle(acpi_handle *phandle)
{
struct acpi_table_ecdt *ecdt_ptr;
acpi_status status;
acpi_handle handle;
status = acpi_get_table(ACPI_SIG_ECDT, 1,
(struct acpi_table_header **)&ecdt_ptr);
if (ACPI_FAILURE(status))
return false;
status = acpi_get_handle(NULL, ecdt_ptr->id, &handle);
if (ACPI_FAILURE(status))
return false;
*phandle = handle;
return true;
}
static bool acpi_is_boot_ec(struct acpi_ec *ec)
{
if (!boot_ec)
return false;
if (ec->handle == boot_ec->handle &&
ec->gpe == boot_ec->gpe &&
ec->command_addr == boot_ec->command_addr &&
ec->data_addr == boot_ec->data_addr)
return true;
return false;
}
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);
ec = acpi_ec_alloc();
if (!ec)
return -ENOMEM;
if (ec_parse_device(device->handle, 0, ec, NULL) !=
AE_CTRL_TERMINATE) {
ret = -EINVAL;
goto err_alloc;
}
if (acpi_is_boot_ec(ec)) {
boot_ec_is_ecdt = false;
acpi_handle_debug(ec->handle, "duplicated.\n");
acpi_ec_free(ec);
ec = boot_ec;
ret = acpi_config_boot_ec(ec, ec->handle, true, false);
} else
ret = acpi_ec_setup(ec, true);
if (ret)
goto err_query;
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);
/* Reprobe devices depending on the EC */
acpi_walk_dep_device_list(ec->handle);
acpi_handle_debug(ec->handle, "enumerated.\n");
return 0;
err_query:
if (ec != boot_ec)
acpi_ec_remove_query_handlers(ec, true, 0);
err_alloc:
if (ec != boot_ec)
acpi_ec_free(ec);
return ret;
}
static int acpi_ec_remove(struct acpi_device *device)
{
struct acpi_ec *ec;
if (!device)
return -EINVAL;
ec = acpi_driver_data(device);
release_region(ec->data_addr, 1);
release_region(ec->command_addr, 1);
device->driver_data = NULL;
if (ec != boot_ec) {
ec_remove_handlers(ec);
acpi_ec_free(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 const struct acpi_device_id ec_device_ids[] = {
{"PNP0C09", 0},
{"", 0},
};
int __init acpi_ec_dsdt_probe(void)
{
acpi_status status;
struct acpi_ec *ec;
int ret;
ec = acpi_ec_alloc();
if (!ec)
return -ENOMEM;
/*
* At this point, the namespace is initialized, so start to find
* the namespace objects.
*/
status = acpi_get_devices(ec_device_ids[0].id,
ec_parse_device, ec, NULL);
if (ACPI_FAILURE(status) || !ec->handle) {
ret = -ENODEV;
goto error;
}
/*
* When the DSDT EC is available, always re-configure boot EC to
* have _REG evaluated. _REG can only be evaluated after the
* namespace initialization.
* At this point, the GPE is not fully initialized, so do not to
* handle the events.
*/
ret = acpi_config_boot_ec(ec, ec->handle, false, false);
error:
if (ret)
acpi_ec_free(ec);
return ret;
}
/*
* If the DSDT EC is not functioning, we still need to prepare a fully
* functioning ECDT EC first in order to handle the events.
* https://bugzilla.kernel.org/show_bug.cgi?id=115021
*/
int __init acpi_ec_ecdt_start(void)
{
acpi_handle handle;
if (!boot_ec)
return -ENODEV;
/*
* The DSDT EC should have already been started in
* acpi_ec_add().
*/
if (!boot_ec_is_ecdt)
return -ENODEV;
/*
* At this point, the namespace and the GPE is initialized, so
* start to find the namespace objects and handle the events.
*/
if (!acpi_ec_ecdt_get_handle(&handle))
return -ENODEV;
return acpi_config_boot_ec(boot_ec, handle, true, true);
}
#if 0
/*
* Some EC firmware variations 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=82611
* https://bugzilla.kernel.org/show_bug.cgi?id=97381
*/
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;
}
#endif
/*
* Some ECDTs contain wrong register addresses.
* MSI MS-171F
* https://bugzilla.kernel.org/show_bug.cgi?id=12461
*/
static int ec_correct_ecdt(const struct dmi_system_id *id)
{
pr_debug("Detected system needing ECDT address correction.\n");
EC_FLAGS_CORRECT_ECDT = 1;
return 0;
}
static struct dmi_system_id ec_dmi_table[] __initdata = {
{
ec_correct_ecdt, "MSI MS-171F", {
DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"),
DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL},
{},
};
int __init acpi_ec_ecdt_probe(void)
{
int ret;
acpi_status status;
struct acpi_table_ecdt *ecdt_ptr;
struct acpi_ec *ec;
ec = acpi_ec_alloc();
if (!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_FAILURE(status)) {
ret = -ENODEV;
goto error;
}
if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) {
/*
* Asus X50GL:
* https://bugzilla.kernel.org/show_bug.cgi?id=11880
*/
ret = -ENODEV;
goto error;
}
if (EC_FLAGS_CORRECT_ECDT) {
ec->command_addr = ecdt_ptr->data.address;
ec->data_addr = ecdt_ptr->control.address;
} else {
ec->command_addr = ecdt_ptr->control.address;
ec->data_addr = ecdt_ptr->data.address;
}
ec->gpe = ecdt_ptr->gpe;
/*
* At this point, the namespace is not initialized, so do not find
* the namespace objects, or handle the events.
*/
ret = acpi_config_boot_ec(ec, ACPI_ROOT_OBJECT, false, true);
error:
if (ret)
acpi_ec_free(ec);
return ret;
}
#ifdef CONFIG_PM_SLEEP
static int acpi_ec_suspend_noirq(struct device *dev)
{
struct acpi_ec *ec =
acpi_driver_data(to_acpi_device(dev));
acpi_ec_enter_noirq(ec);
return 0;
}
static int acpi_ec_resume_noirq(struct device *dev)
{
struct acpi_ec *ec =
acpi_driver_data(to_acpi_device(dev));
acpi_ec_leave_noirq(ec);
return 0;
}
static int acpi_ec_suspend(struct device *dev)
{
struct acpi_ec *ec =
acpi_driver_data(to_acpi_device(dev));
if (ec_freeze_events)
acpi_ec_disable_event(ec);
return 0;
}
static int acpi_ec_resume(struct device *dev)
{
struct acpi_ec *ec =
acpi_driver_data(to_acpi_device(dev));
acpi_ec_enable_event(ec);
return 0;
}
#endif
static const struct dev_pm_ops acpi_ec_pm = {
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq)
SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume)
};
static int param_set_event_clearing(const char *val, struct kernel_param *kp)
{
int result = 0;
if (!strncmp(val, "status", sizeof("status") - 1)) {
ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS;
pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n");
} else if (!strncmp(val, "query", sizeof("query") - 1)) {
ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY;
pr_info("Assuming SCI_EVT clearing on QR_EC writes\n");
} else if (!strncmp(val, "event", sizeof("event") - 1)) {
ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT;
pr_info("Assuming SCI_EVT clearing on event reads\n");
} else
result = -EINVAL;
return result;
}
static int param_get_event_clearing(char *buffer, struct kernel_param *kp)
{
switch (ec_event_clearing) {
case ACPI_EC_EVT_TIMING_STATUS:
return sprintf(buffer, "status");
case ACPI_EC_EVT_TIMING_QUERY:
return sprintf(buffer, "query");
case ACPI_EC_EVT_TIMING_EVENT:
return sprintf(buffer, "event");
default:
return sprintf(buffer, "invalid");
}
return 0;
}
module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing,
NULL, 0644);
MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing");
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,
},
.drv.pm = &acpi_ec_pm,
};
static inline int acpi_ec_query_init(void)
{
if (!ec_query_wq) {
ec_query_wq = alloc_workqueue("kec_query", 0,
ec_max_queries);
if (!ec_query_wq)
return -ENODEV;
}
return 0;
}
static inline void acpi_ec_query_exit(void)
{
if (ec_query_wq) {
destroy_workqueue(ec_query_wq);
ec_query_wq = NULL;
}
}
int __init acpi_ec_init(void)
{
int result;
/* register workqueue for _Qxx evaluations */
result = acpi_ec_query_init();
if (result)
goto err_exit;
/* Now register the driver for the EC */
result = acpi_bus_register_driver(&acpi_ec_driver);
if (result)
goto err_exit;
err_exit:
if (result)
acpi_ec_query_exit();
return result;
}
/* EC driver currently not unloadable */
#if 0
static void __exit acpi_ec_exit(void)
{
acpi_bus_unregister_driver(&acpi_ec_driver);
acpi_ec_query_exit();
}
#endif /* 0 */
View git blame Copy permalink