diff options
author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2015-02-10 14:59:13 (GMT) |
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committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2015-02-10 14:59:13 (GMT) |
commit | 716bc4132aa0da4627fee108a08a39e914fde693 (patch) | |
tree | 500a31a3053054368930a6e2d2c4c4b9305af085 /drivers | |
parent | 55c39fc2b18c384f51d8ed47678cca851b80a063 (diff) | |
parent | b5bca896ef3c4dd8aa1aac55256cb094c7376a77 (diff) | |
download | linux-716bc4132aa0da4627fee108a08a39e914fde693.tar.xz |
Merge branch 'acpi-ec'
* acpi-ec:
ACPI / EC: Add GPE reference counting debugging messages
ACPI / EC: Add query flushing support
ACPI / EC: Refine command storm prevention support
ACPI / EC: Add command flushing support.
ACPI / EC: Introduce STARTED/STOPPED flags to replace BLOCKED flag
ACPI / EC: Update revision due to raw handler mode.
ACPI / EC: Reduce ec_poll() by referencing the last register access timestamp.
ACPI / EC: Fix several GPE handling issues by deploying ACPI_GPE_DISPATCH_RAW_HANDLER mode.
ACPI / EC: Cleanup QR_EC related code
ACPI / EC: Fix issues related to the SCI_EVT handling
ACPI / EC: Fix a code path that global lock is not held
ACPI / EC: Fix returning values in acpi_ec_sync_query()
ACPI / EC: Add reference counting for query handlers
ACPI / EC: Cleanup transaction wakeup code
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/acpi/ec.c | 548 | ||||
-rw-r--r-- | drivers/acpi/internal.h | 2 |
2 files changed, 419 insertions, 131 deletions
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index 1b5853f..14d0c89 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -1,8 +1,8 @@ /* - * ec.c - ACPI Embedded Controller Driver (v2.2) + * ec.c - ACPI Embedded Controller Driver (v3) * - * Copyright (C) 2001-2014 Intel Corporation - * Author: 2014 Lv Zheng <lv.zheng@intel.com> + * 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> @@ -31,6 +31,7 @@ /* Uncomment next line to get verbose printout */ /* #define DEBUG */ +#define DEBUG_REF 0 #define pr_fmt(fmt) "ACPI : EC: " fmt #include <linux/kernel.h> @@ -71,20 +72,32 @@ enum ec_command { #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_GPE_STORM, /* GPE storm detected */ + EC_FLAGS_EVENT_ENABLED, /* Event is enabled */ + EC_FLAGS_EVENT_PENDING, /* Event is pending */ + EC_FLAGS_EVENT_DETECTED, /* Event is detected */ EC_FLAGS_HANDLERS_INSTALLED, /* Handlers for GPE and * OpReg are installed */ - EC_FLAGS_BLOCKED, /* Transactions are blocked */ + 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 */ +#define ec_debug_ref(ec, fmt, ...) \ + do { \ + if (DEBUG_REF) \ + pr_debug("%lu: " fmt, ec->reference_count, \ + ## __VA_ARGS__); \ + } while (0) + /* 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); @@ -105,6 +118,7 @@ struct acpi_ec_query_handler { acpi_handle handle; void *data; u8 query_bit; + struct kref kref; }; struct transaction { @@ -117,8 +131,12 @@ struct transaction { 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); @@ -129,7 +147,28 @@ 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 */ /* -------------------------------------------------------------------------- - * Transaction Management + * 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; +} + +static bool acpi_ec_has_pending_event(struct acpi_ec *ec) +{ + return test_bit(EC_FLAGS_EVENT_DETECTED, &ec->flags) || + test_bit(EC_FLAGS_EVENT_PENDING, &ec->flags); +} + +/* -------------------------------------------------------------------------- + * EC Registers * -------------------------------------------------------------------------- */ static inline u8 acpi_ec_read_status(struct acpi_ec *ec) @@ -151,6 +190,7 @@ static inline u8 acpi_ec_read_data(struct acpi_ec *ec) { u8 x = inb(ec->data_addr); + ec->curr->timestamp = jiffies; pr_debug("EC_DATA(R) = 0x%2.2x\n", x); return x; } @@ -159,12 +199,14 @@ static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command) { pr_debug("EC_SC(W) = 0x%2.2x\n", command); outb(command, ec->command_addr); + ec->curr->timestamp = jiffies; } static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data) { pr_debug("EC_DATA(W) = 0x%2.2x\n", data); outb(data, ec->data_addr); + ec->curr->timestamp = jiffies; } #ifdef DEBUG @@ -188,6 +230,203 @@ static const char *acpi_ec_cmd_string(u8 cmd) #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. + */ + pr_debug("***** Polling quirk *****\n"); + 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); + pr_debug("+++++ Polling enabled +++++\n"); + 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); + pr_debug("+++++ Polling disabled +++++\n"); + } +} + +/* + * acpi_ec_submit_flushable_request() - Increase the reference count unless + * the flush operation is not in + * progress + * @ec: the EC device + * @allow_event: whether event should be handled + * + * 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. + * + * During flushing, QR_EC command need to pass this check when there is a + * pending event, so that the reference count held for the pending event + * can be decreased by the completion of the QR_EC command. + */ +static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec, + bool allow_event) +{ + if (!acpi_ec_started(ec)) { + if (!allow_event || !acpi_ec_has_pending_event(ec)) + return false; + } + acpi_ec_submit_request(ec); + return true; +} + +static void acpi_ec_submit_event(struct acpi_ec *ec) +{ + if (!test_bit(EC_FLAGS_EVENT_DETECTED, &ec->flags) || + !test_bit(EC_FLAGS_EVENT_ENABLED, &ec->flags)) + return; + /* Hold reference for pending event */ + if (!acpi_ec_submit_flushable_request(ec, true)) + return; + ec_debug_ref(ec, "Increase event\n"); + if (!test_and_set_bit(EC_FLAGS_EVENT_PENDING, &ec->flags)) { + pr_debug("***** Event query started *****\n"); + schedule_work(&ec->work); + return; + } + acpi_ec_complete_request(ec); + ec_debug_ref(ec, "Decrease event\n"); +} + +static void acpi_ec_complete_event(struct acpi_ec *ec) +{ + if (ec->curr->command == ACPI_EC_COMMAND_QUERY) { + clear_bit(EC_FLAGS_EVENT_PENDING, &ec->flags); + pr_debug("***** Event query stopped *****\n"); + /* Unhold reference for pending event */ + acpi_ec_complete_request(ec); + ec_debug_ref(ec, "Decrease event\n"); + /* Check if there is another SCI_EVT detected */ + acpi_ec_submit_event(ec); + } +} + +static void acpi_ec_submit_detection(struct acpi_ec *ec) +{ + /* Hold reference for query submission */ + if (!acpi_ec_submit_flushable_request(ec, false)) + return; + ec_debug_ref(ec, "Increase query\n"); + if (!test_and_set_bit(EC_FLAGS_EVENT_DETECTED, &ec->flags)) { + pr_debug("***** Event detection blocked *****\n"); + acpi_ec_submit_event(ec); + return; + } + acpi_ec_complete_request(ec); + ec_debug_ref(ec, "Decrease query\n"); +} + +static void acpi_ec_complete_detection(struct acpi_ec *ec) +{ + if (ec->curr->command == ACPI_EC_COMMAND_QUERY) { + clear_bit(EC_FLAGS_EVENT_DETECTED, &ec->flags); + pr_debug("***** Event detetion unblocked *****\n"); + /* Unhold reference for query submission */ + acpi_ec_complete_request(ec); + ec_debug_ref(ec, "Decrease query\n"); + } +} + +static void acpi_ec_enable_event(struct acpi_ec *ec) +{ + unsigned long flags; + + spin_lock_irqsave(&ec->lock, flags); + set_bit(EC_FLAGS_EVENT_ENABLED, &ec->flags); + /* + * An event may be pending even with SCI_EVT=0, so QR_EC should + * always be issued right after started. + */ + acpi_ec_submit_detection(ec); + spin_unlock_irqrestore(&ec->lock, flags); +} + static int ec_transaction_completed(struct acpi_ec *ec) { unsigned long flags; @@ -200,7 +439,7 @@ static int ec_transaction_completed(struct acpi_ec *ec) return ret; } -static bool advance_transaction(struct acpi_ec *ec) +static void advance_transaction(struct acpi_ec *ec) { struct transaction *t; u8 status; @@ -208,6 +447,12 @@ static bool advance_transaction(struct acpi_ec *ec) pr_debug("===== %s (%d) =====\n", 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) @@ -223,6 +468,7 @@ static bool advance_transaction(struct acpi_ec *ec) t->rdata[t->ri++] = acpi_ec_read_data(ec); if (t->rlen == t->ri) { t->flags |= ACPI_EC_COMMAND_COMPLETE; + acpi_ec_complete_event(ec); if (t->command == ACPI_EC_COMMAND_QUERY) pr_debug("***** Command(%s) hardware completion *****\n", acpi_ec_cmd_string(t->command)); @@ -233,25 +479,29 @@ static bool advance_transaction(struct acpi_ec *ec) } else if (t->wlen == t->wi && (status & ACPI_EC_FLAG_IBF) == 0) { t->flags |= ACPI_EC_COMMAND_COMPLETE; + acpi_ec_complete_event(ec); wakeup = true; } - return wakeup; + 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_detection(ec); t->rdata[t->ri++] = 0x00; t->flags |= ACPI_EC_COMMAND_COMPLETE; + acpi_ec_complete_event(ec); pr_debug("***** Command(%s) software completion *****\n", 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_detection(ec); } else goto err; - return wakeup; + goto out; } err: /* @@ -259,28 +509,27 @@ err: * otherwise will take a not handled IRQ as a false one. */ if (!(status & ACPI_EC_FLAG_SCI)) { - if (in_interrupt() && t) - ++t->irq_count; + 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); + } } - return wakeup; +out: + if (status & ACPI_EC_FLAG_SCI) + acpi_ec_submit_detection(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; - (void)advance_transaction(ec); -} - -static int acpi_ec_sync_query(struct acpi_ec *ec, u8 *data); - -static int ec_check_sci_sync(struct acpi_ec *ec, u8 state) -{ - if (state & ACPI_EC_FLAG_SCI) { - if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) - return acpi_ec_sync_query(ec, NULL); - } - return 0; + ec->curr->timestamp = jiffies; + advance_transaction(ec); } static int ec_poll(struct acpi_ec *ec) @@ -291,20 +540,25 @@ static int ec_poll(struct acpi_ec *ec) 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()) { - udelay(ACPI_EC_MSI_UDELAY); + 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), - msecs_to_jiffies(1))) + usecs_to_jiffies(usecs))) return 0; } spin_lock_irqsave(&ec->lock, flags); - (void)advance_transaction(ec); + 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"); @@ -325,21 +579,29 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 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, true)) { + ret = -EINVAL; + goto unlock; + } + ec_debug_ref(ec, "Increase command\n"); /* following two actions should be kept atomic */ ec->curr = t; pr_debug("***** Command(%s) started *****\n", acpi_ec_cmd_string(t->command)); start_transaction(ec); - if (ec->curr->command == ACPI_EC_COMMAND_QUERY) { - clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); - pr_debug("***** Event stopped *****\n"); - } 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); pr_debug("***** Command(%s) stopped *****\n", acpi_ec_cmd_string(t->command)); ec->curr = NULL; + /* Disable GPE for command processing (IBF=0/OBF=1) */ + acpi_ec_complete_request(ec); + ec_debug_ref(ec, "Decrease command\n"); +unlock: spin_unlock_irqrestore(&ec->lock, tmp); return ret; } @@ -354,10 +616,6 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) if (t->rdata) memset(t->rdata, 0, t->rlen); mutex_lock(&ec->mutex); - if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) { - status = -EINVAL; - goto unlock; - } if (ec->global_lock) { status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); if (ACPI_FAILURE(status)) { @@ -365,26 +623,11 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) goto unlock; } } - /* disable GPE during transaction if storm is detected */ - if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) { - /* It has to be disabled, so that it doesn't trigger. */ - acpi_disable_gpe(NULL, ec->gpe); - } status = acpi_ec_transaction_unlocked(ec, t); - /* check if we received SCI during transaction */ - ec_check_sci_sync(ec, acpi_ec_read_status(ec)); - if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) { + if (test_bit(EC_FLAGS_COMMAND_STORM, &ec->flags)) msleep(1); - /* It is safe to enable the GPE outside of the transaction. */ - acpi_enable_gpe(NULL, ec->gpe); - } else if (t->irq_count > ec_storm_threshold) { - pr_info("GPE storm detected(%d GPEs), " - "transactions will use polling mode\n", - t->irq_count); - set_bit(EC_FLAGS_GPE_STORM, &ec->flags); - } if (ec->global_lock) acpi_release_global_lock(glk); unlock: @@ -500,7 +743,7 @@ static void acpi_ec_clear(struct acpi_ec *ec) u8 value = 0; for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) { - status = acpi_ec_sync_query(ec, &value); + status = acpi_ec_query(ec, &value); if (status || !value) break; } @@ -511,6 +754,57 @@ static void acpi_ec_clear(struct acpi_ec *ec) 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)) { + pr_debug("+++++ Starting EC +++++\n"); + /* Enable GPE for event processing (SCI_EVT=1) */ + if (!resuming) { + acpi_ec_submit_request(ec); + ec_debug_ref(ec, "Increase driver\n"); + } + pr_info("+++++ EC started +++++\n"); + } + 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)) { + pr_debug("+++++ Stopping EC +++++\n"); + 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_debug_ref(ec, "Decrease driver\n"); + } + clear_bit(EC_FLAGS_STARTED, &ec->flags); + clear_bit(EC_FLAGS_STOPPED, &ec->flags); + pr_info("+++++ EC stopped +++++\n"); + } + spin_unlock_irqrestore(&ec->lock, flags); +} + void acpi_ec_block_transactions(void) { struct acpi_ec *ec = first_ec; @@ -520,7 +814,7 @@ void acpi_ec_block_transactions(void) mutex_lock(&ec->mutex); /* Prevent transactions from being carried out */ - set_bit(EC_FLAGS_BLOCKED, &ec->flags); + acpi_ec_stop(ec, true); mutex_unlock(&ec->mutex); } @@ -531,14 +825,11 @@ void acpi_ec_unblock_transactions(void) if (!ec) return; - mutex_lock(&ec->mutex); /* Allow transactions to be carried out again */ - clear_bit(EC_FLAGS_BLOCKED, &ec->flags); + acpi_ec_start(ec, true); if (EC_FLAGS_CLEAR_ON_RESUME) acpi_ec_clear(ec); - - mutex_unlock(&ec->mutex); } void acpi_ec_unblock_transactions_early(void) @@ -548,36 +839,33 @@ void acpi_ec_unblock_transactions_early(void) * atomic context during wakeup, so we don't need to acquire the mutex). */ if (first_ec) - clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags); + acpi_ec_start(first_ec, true); } -static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 *data) +/* -------------------------------------------------------------------------- + Event Management + -------------------------------------------------------------------------- */ +static struct acpi_ec_query_handler * +acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler) { - int result; - u8 d; - struct transaction t = {.command = ACPI_EC_COMMAND_QUERY, - .wdata = NULL, .rdata = &d, - .wlen = 0, .rlen = 1}; + if (handler) + kref_get(&handler->kref); + return handler; +} - if (!ec || !data) - return -EINVAL; - /* - * Query the EC to find out which _Qxx method we need to evaluate. - * Note that successful completion of the query causes the ACPI_EC_SCI - * bit to be cleared (and thus clearing the interrupt source). - */ - result = acpi_ec_transaction_unlocked(ec, &t); - if (result) - return result; - if (!d) - return -ENODATA; - *data = d; - return 0; +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); } -/* -------------------------------------------------------------------------- - Event Management - -------------------------------------------------------------------------- */ int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, acpi_handle handle, acpi_ec_query_func func, void *data) @@ -593,6 +881,7 @@ int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 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; @@ -602,15 +891,18 @@ 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(&handler->node); - kfree(handler); + 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); @@ -626,59 +918,58 @@ static void acpi_ec_run(void *cxt) else if (handler->handle) acpi_evaluate_object(handler->handle, NULL, NULL, NULL); pr_debug("##### Query(0x%02x) stopped #####\n", handler->query_bit); - kfree(handler); + acpi_ec_put_query_handler(handler); } -static int acpi_ec_sync_query(struct acpi_ec *ec, u8 *data) +static int acpi_ec_query(struct acpi_ec *ec, u8 *data) { u8 value = 0; - int status; - struct acpi_ec_query_handler *handler, *copy; + 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}; - status = acpi_ec_query_unlocked(ec, &value); + /* + * 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 (status) - return status; + 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 */ - copy = kmalloc(sizeof(*handler), GFP_KERNEL); - if (!copy) - return -ENOMEM; - memcpy(copy, handler, sizeof(*copy)); + handler = acpi_ec_get_query_handler(handler); pr_debug("##### Query(0x%02x) scheduled #####\n", handler->query_bit); - return acpi_os_execute((copy->func) ? + status = acpi_os_execute((handler->func) ? OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER, - acpi_ec_run, copy); + acpi_ec_run, handler); + if (ACPI_FAILURE(status)) + result = -EBUSY; + break; } } - return 0; -} - -static void acpi_ec_gpe_query(void *ec_cxt) -{ - struct acpi_ec *ec = ec_cxt; - - if (!ec) - return; - mutex_lock(&ec->mutex); - acpi_ec_sync_query(ec, NULL); mutex_unlock(&ec->mutex); + return result; } -static int ec_check_sci(struct acpi_ec *ec, u8 state) +static void acpi_ec_gpe_poller(struct work_struct *work) { - if (state & ACPI_EC_FLAG_SCI) { - if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { - pr_debug("***** Event started *****\n"); - return acpi_os_execute(OSL_NOTIFY_HANDLER, - acpi_ec_gpe_query, ec); - } - } - return 0; + struct acpi_ec *ec = container_of(work, struct acpi_ec, work); + + pr_debug("***** Event poller started *****\n"); + acpi_ec_query(ec, NULL); + pr_debug("***** Event poller stopped *****\n"); } static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, @@ -688,11 +979,9 @@ static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, struct acpi_ec *ec = data; spin_lock_irqsave(&ec->lock, flags); - if (advance_transaction(ec)) - wake_up(&ec->wait); + advance_transaction(ec); spin_unlock_irqrestore(&ec->lock, flags); - ec_check_sci(ec, acpi_ec_read_status(ec)); - return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE; + return ACPI_INTERRUPT_HANDLED; } /* -------------------------------------------------------------------------- @@ -750,11 +1039,11 @@ static struct acpi_ec *make_acpi_ec(void) 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; } @@ -810,13 +1099,13 @@ static int ec_install_handlers(struct acpi_ec *ec) if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags)) return 0; - status = acpi_install_gpe_handler(NULL, ec->gpe, + 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_enable_gpe(NULL, ec->gpe); + acpi_ec_start(ec, false); status = acpi_install_address_space_handler(ec->handle, ACPI_ADR_SPACE_EC, &acpi_ec_space_handler, @@ -831,7 +1120,7 @@ static int ec_install_handlers(struct acpi_ec *ec) pr_err("Fail in evaluating the _REG object" " of EC device. Broken bios is suspected.\n"); } else { - acpi_disable_gpe(NULL, ec->gpe); + acpi_ec_stop(ec, false); acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler); return -ENODEV; @@ -846,7 +1135,7 @@ static void ec_remove_handlers(struct acpi_ec *ec) { if (!test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags)) return; - acpi_disable_gpe(NULL, ec->gpe); + 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"); @@ -900,14 +1189,11 @@ static int acpi_ec_add(struct acpi_device *device) ret = ec_install_handlers(ec); /* EC is fully operational, allow queries */ - clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); + acpi_ec_enable_event(ec); /* Clear stale _Q events if hardware might require that */ - if (EC_FLAGS_CLEAR_ON_RESUME) { - mutex_lock(&ec->mutex); + if (EC_FLAGS_CLEAR_ON_RESUME) acpi_ec_clear(ec); - mutex_unlock(&ec->mutex); - } return ret; } diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index 163e82f..7dc69d8 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -122,11 +122,13 @@ struct acpi_ec { unsigned long data_addr; unsigned long global_lock; unsigned long flags; + unsigned long reference_count; struct mutex mutex; wait_queue_head_t wait; struct list_head list; struct transaction *curr; spinlock_t lock; + struct work_struct work; }; extern struct acpi_ec *first_ec; |