// SPDX-License-Identifier: GPL-2.0-or-later /* * ec.c - ACPI Embedded Controller Driver (v3) * * Copyright (C) 2001-2015 Intel Corporation * Author: 2014, 2015 Lv Zheng * 2006, 2007 Alexey Starikovskiy * 2006 Denis Sadykov * 2004 Luming Yu * 2001, 2002 Andy Grover * 2001, 2002 Paul Diefenbaugh * Copyright (C) 2008 Alexey Starikovskiy */ /* Uncomment next line to get verbose printout */ /* #define DEBUG */ #define pr_fmt(fmt) "ACPI: EC: " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include "internal.h" #define ACPI_EC_CLASS "embedded_controller" #define ACPI_EC_DEVICE_NAME "Embedded Controller" /* 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_EVENT_HANDLER_INSTALLED, /* Event handler installed */ EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */ EC_FLAGS_EC_REG_CALLED, /* OpReg ACPI _REG method called */ EC_FLAGS_QUERY_METHODS_INSTALLED, /* _Qxx handlers installed */ EC_FLAGS_STARTED, /* Driver is started */ EC_FLAGS_STOPPED, /* Driver is stopped */ EC_FLAGS_EVENTS_MASKED, /* Events masked */ }; #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; module_param(ec_freeze_events, bool, 0644); MODULE_PARM_DESC(ec_freeze_events, "Disabling event handling during suspend/resume"); static bool ec_no_wakeup __read_mostly; module_param(ec_no_wakeup, bool, 0644); MODULE_PARM_DESC(ec_no_wakeup, "Do not wake up from suspend-to-idle"); 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; struct acpi_ec *ec; }; static int acpi_ec_submit_query(struct acpi_ec *ec); static void advance_transaction(struct acpi_ec *ec, bool interrupt); static void acpi_ec_event_handler(struct work_struct *work); struct acpi_ec *first_ec; EXPORT_SYMBOL(first_ec); static struct acpi_ec *boot_ec; static bool boot_ec_is_ecdt; static struct workqueue_struct *ec_wq; static struct workqueue_struct *ec_query_wq; static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */ static int EC_FLAGS_TRUST_DSDT_GPE; /* Needs DSDT GPE as correction setting */ static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ /* -------------------------------------------------------------------------- * 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; } #if defined(DEBUG) || defined(CONFIG_DYNAMIC_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_gpe_status_set(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); } 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_gpe_status_set(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, false); } } 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); } } /* -------------------------------------------------------------------------- * Transaction Management * -------------------------------------------------------------------------- */ static void acpi_ec_submit_request(struct acpi_ec *ec) { ec->reference_count++; if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags) && ec->gpe >= 0 && 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_EVENT_HANDLER_INSTALLED, &ec->flags) && ec->gpe >= 0 && 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_mask_events(struct acpi_ec *ec) { if (!test_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags)) { if (ec->gpe >= 0) acpi_ec_disable_gpe(ec, false); else disable_irq_nosync(ec->irq); ec_dbg_drv("Polling enabled"); set_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags); } } static void acpi_ec_unmask_events(struct acpi_ec *ec) { if (test_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags)) { clear_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags); if (ec->gpe >= 0) acpi_ec_enable_gpe(ec, false); else enable_irq(ec->irq); 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_event(struct acpi_ec *ec) { /* * It is safe to mask the events here, because acpi_ec_close_event() * will run at least once after this. */ acpi_ec_mask_events(ec); if (!acpi_ec_event_enabled(ec)) return; if (ec->event_state != EC_EVENT_READY) return; ec_dbg_evt("Command(%s) submitted/blocked", acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); ec->event_state = EC_EVENT_IN_PROGRESS; /* * If events_to_process is greater than 0 at this point, the while () * loop in acpi_ec_event_handler() is still running and incrementing * events_to_process will cause it to invoke acpi_ec_submit_query() once * more, so it is not necessary to queue up the event work to start the * same loop again. */ if (ec->events_to_process++ > 0) return; ec->events_in_progress++; queue_work(ec_wq, &ec->work); } static void acpi_ec_complete_event(struct acpi_ec *ec) { if (ec->event_state == EC_EVENT_IN_PROGRESS) ec->event_state = EC_EVENT_COMPLETE; } static void acpi_ec_close_event(struct acpi_ec *ec) { if (ec->event_state != EC_EVENT_READY) ec_dbg_evt("Command(%s) unblocked", acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); ec->event_state = EC_EVENT_READY; acpi_ec_unmask_events(ec); } 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"); /* * Unconditionally invoke this once after enabling the event * handling mechanism to detect the pending events. */ advance_transaction(ec, false); } 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"); } /* * 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; for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) { if (acpi_ec_submit_query(ec)) 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_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); /* Drain additional events if hardware requires that */ if (EC_FLAGS_CLEAR_ON_RESUME) acpi_ec_clear(ec); } #ifdef CONFIG_PM_SLEEP static void __acpi_ec_flush_work(void) { flush_workqueue(ec_wq); /* flush ec->work */ flush_workqueue(ec_query_wq); /* flush queries */ } 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); /* * When ec_freeze_events is true, we need to flush events in * the proper position before entering the noirq stage. */ __acpi_ec_flush_work(); } void acpi_ec_flush_work(void) { /* Without ec_wq there is nothing to flush. */ if (!ec_wq) return; __acpi_ec_flush_work(); } #endif /* CONFIG_PM_SLEEP */ static bool acpi_ec_guard_event(struct acpi_ec *ec) { unsigned long flags; bool guarded; 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 is applicable if the event state is not * EC_EVENT_READY, but otherwise if the current transaction is of the * ACPI_EC_COMMAND_QUERY type, the guarding should have elapsed already * and it should not be applied to let the transaction transition into * the ACPI_EC_COMMAND_POLL state immediately. */ guarded = ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && ec->event_state != EC_EVENT_READY && (!ec->curr || ec->curr->command != ACPI_EC_COMMAND_QUERY); 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) return; switch (ec_event_clearing) { case ACPI_EC_EVT_TIMING_STATUS: if (flag == ACPI_EC_COMMAND_POLL) acpi_ec_close_event(ec); return; case ACPI_EC_EVT_TIMING_QUERY: if (flag == ACPI_EC_COMMAND_COMPLETE) acpi_ec_close_event(ec); return; case ACPI_EC_EVT_TIMING_EVENT: if (flag == ACPI_EC_COMMAND_COMPLETE) acpi_ec_complete_event(ec); } } static void acpi_ec_spurious_interrupt(struct acpi_ec *ec, struct transaction *t) { if (t->irq_count < ec_storm_threshold) ++t->irq_count; /* Trigger if the threshold is 0 too. */ if (t->irq_count == ec_storm_threshold) acpi_ec_mask_events(ec); } static void advance_transaction(struct acpi_ec *ec, bool interrupt) { struct transaction *t = ec->curr; bool wakeup = false; u8 status; ec_dbg_stm("%s (%d)", interrupt ? "IRQ" : "TASK", smp_processor_id()); status = acpi_ec_read_status(ec); /* * 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->event_state == EC_EVENT_COMPLETE) acpi_ec_close_event(ec); if (!t) goto out; } if (t->flags & ACPI_EC_COMMAND_POLL) { if (t->wlen > t->wi) { if (!(status & ACPI_EC_FLAG_IBF)) acpi_ec_write_data(ec, t->wdata[t->wi++]); else if (interrupt && !(status & ACPI_EC_FLAG_SCI)) acpi_ec_spurious_interrupt(ec, t); } else if (t->rlen > t->ri) { if (status & ACPI_EC_FLAG_OBF) { t->rdata[t->ri++] = acpi_ec_read_data(ec); if (t->rlen == t->ri) { ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); wakeup = true; if (t->command == ACPI_EC_COMMAND_QUERY) ec_dbg_evt("Command(%s) completed by hardware", acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); } } else if (interrupt && !(status & ACPI_EC_FLAG_SCI)) { acpi_ec_spurious_interrupt(ec, t); } } else if (t->wlen == t->wi && !(status & ACPI_EC_FLAG_IBF)) { ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); wakeup = true; } } else if (!(status & ACPI_EC_FLAG_IBF)) { acpi_ec_write_cmd(ec, t->command); ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); } out: if (status & ACPI_EC_FLAG_SCI) acpi_ec_submit_event(ec); if (wakeup && 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, false); 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 (t->rdata) memset(t->rdata, 0, t->rlen); /* 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_unmask_events(ec); 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; 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_unlocked(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_unlocked(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_read_unlocked(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_unlocked(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); } static int acpi_ec_write_unlocked(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_unlocked(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) { if (!first_ec) return -ENODEV; return acpi_ec_write(first_ec, addr, val); } 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_by_value(struct acpi_ec *ec, u8 value) { struct acpi_ec_query_handler *handler; mutex_lock(&ec->mutex); list_for_each_entry(handler, &ec->list, node) { if (value == handler->query_bit) { kref_get(&handler->kref); mutex_unlock(&ec->mutex); return handler; } } mutex_unlock(&ec->mutex); return 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; if (!handle && !func) return -EINVAL; handler = kzalloc(sizeof(*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) { /* * When remove_all is false, only remove custom query handlers * which have handler->func set. This is done to preserve query * handlers discovered thru ACPI, as they should continue handling * EC queries. */ if (remove_all || (handler->func && handler->query_bit == 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); flush_workqueue(ec_query_wq); } EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 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; struct acpi_ec *ec = q->ec; 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); spin_lock_irq(&ec->lock); ec->queries_in_progress--; spin_unlock_irq(&ec->lock); acpi_ec_put_query_handler(handler); kfree(q); } static struct acpi_ec_query *acpi_ec_create_query(struct acpi_ec *ec, 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; q->ec = ec; return q; } static int acpi_ec_submit_query(struct acpi_ec *ec) { struct acpi_ec_query *q; u8 value = 0; int result; q = acpi_ec_create_query(ec, &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 (result) goto err_exit; if (!value) { result = -ENODATA; 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 queue_work() to make it appear in the log * before any other messages emitted during workqueue handling. */ ec_dbg_evt("Query(0x%02x) scheduled", value); spin_lock_irq(&ec->lock); ec->queries_in_progress++; queue_work(ec_query_wq, &q->work); spin_unlock_irq(&ec->lock); return 0; err_exit: kfree(q); return result; } static void acpi_ec_event_handler(struct work_struct *work) { struct acpi_ec *ec = container_of(work, struct acpi_ec, work); ec_dbg_evt("Event started"); spin_lock_irq(&ec->lock); while (ec->events_to_process) { spin_unlock_irq(&ec->lock); acpi_ec_submit_query(ec); spin_lock_irq(&ec->lock); ec->events_to_process--; } /* * Before exit, make sure that the it will be possible to queue up the * event handling work again regardless of whether or not the query * queued up above is processed successfully. */ if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { bool guard_timeout; acpi_ec_complete_event(ec); ec_dbg_evt("Event stopped"); spin_unlock_irq(&ec->lock); guard_timeout = !!ec_guard(ec); spin_lock_irq(&ec->lock); /* Take care of SCI_EVT unless someone else is doing that. */ if (guard_timeout && !ec->curr) advance_transaction(ec, false); } else { acpi_ec_close_event(ec); ec_dbg_evt("Event stopped"); } ec->events_in_progress--; spin_unlock_irq(&ec->lock); } static void clear_gpe_and_advance_transaction(struct acpi_ec *ec, bool interrupt) { /* * Clear GPE_STS upfront to allow subsequent hardware GPE_STS 0->1 * changes to always trigger a GPE interrupt. * * GPE STS is a W1C register, which means: * * 1. Software can clear it without worrying about clearing the 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. */ if (ec->gpe >= 0 && acpi_ec_gpe_status_set(ec)) acpi_clear_gpe(NULL, ec->gpe); advance_transaction(ec, true); } static void acpi_ec_handle_interrupt(struct acpi_ec *ec) { unsigned long flags; spin_lock_irqsave(&ec->lock, flags); clear_gpe_and_advance_transaction(ec, true); spin_unlock_irqrestore(&ec->lock, flags); } static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, u32 gpe_number, void *data) { acpi_ec_handle_interrupt(data); return ACPI_INTERRUPT_HANDLED; } static irqreturn_t acpi_ec_irq_handler(int irq, void *data) { acpi_ec_handle_interrupt(data); return IRQ_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; u32 glk; if ((address > 0xFF) || !value || !handler_context) return AE_BAD_PARAMETER; if (function != ACPI_READ && function != ACPI_WRITE) return AE_BAD_PARAMETER; mutex_lock(&ec->mutex); if (ec->global_lock) { acpi_status status; status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); if (ACPI_FAILURE(status)) { result = -ENODEV; goto unlock; } } 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_unlocked(ec, address, value) : acpi_ec_write_unlocked(ec, address, *value); if (result < 0) break; } if (ec->busy_polling || bits > 8) acpi_ec_burst_disable(ec); if (ec->global_lock) acpi_release_global_lock(glk); unlock: mutex_unlock(&ec->mutex); switch (result) { case -EINVAL: return AE_BAD_PARAMETER; case -ENODEV: return AE_NOT_FOUND; case -ETIME: return AE_TIME; case 0: return AE_OK; default: return AE_ERROR; } } /* -------------------------------------------------------------------------- * 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; ec->gpe = -1; ec->irq = -1; 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; if (ec->data_addr == 0 || ec->command_addr == 0) return AE_OK; /* Get GPE bit assignment (EC events). */ /* TODO: Add support for _GPE returning a package */ status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); if (ACPI_SUCCESS(status)) ec->gpe = tmp; /* * Errors are non-fatal, allowing for ACPI Reduced Hardware * platforms which use GpioInt instead of GPE. */ /* 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 bool install_gpe_event_handler(struct acpi_ec *ec) { acpi_status status; status = acpi_install_gpe_raw_handler(NULL, ec->gpe, ACPI_GPE_EDGE_TRIGGERED, &acpi_ec_gpe_handler, ec); if (ACPI_FAILURE(status)) return false; if (test_bit(EC_FLAGS_STARTED, &ec->flags) && ec->reference_count >= 1) acpi_ec_enable_gpe(ec, true); return true; } static bool install_gpio_irq_event_handler(struct acpi_ec *ec) { return request_threaded_irq(ec->irq, NULL, acpi_ec_irq_handler, IRQF_SHARED | IRQF_ONESHOT, "ACPI EC", ec) >= 0; } /** * ec_install_handlers - Install service callbacks and register query methods. * @ec: Target EC. * @device: ACPI device object corresponding to @ec. * @call_reg: If _REG should be called to notify OpRegion availability * * Install a handler for the EC address space type unless it has been installed * already. If @device is not NULL, also look for EC query methods in the * namespace and register them, and install an event (either GPE or GPIO IRQ) * handler for the EC, if possible. * * Return: * -ENODEV if the address space handler cannot be installed, which means * "unable to handle transactions", * -EPROBE_DEFER if GPIO IRQ acquisition needs to be deferred, * or 0 (success) otherwise. */ static int ec_install_handlers(struct acpi_ec *ec, struct acpi_device *device, bool call_reg) { acpi_status status; acpi_ec_start(ec, false); if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { acpi_handle scope_handle = ec == first_ec ? ACPI_ROOT_OBJECT : ec->handle; acpi_ec_enter_noirq(ec); status = acpi_install_address_space_handler_no_reg(scope_handle, ACPI_ADR_SPACE_EC, &acpi_ec_space_handler, NULL, ec); if (ACPI_FAILURE(status)) { acpi_ec_stop(ec, false); return -ENODEV; } set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); } if (call_reg && !test_bit(EC_FLAGS_EC_REG_CALLED, &ec->flags)) { acpi_execute_reg_methods(ec->handle, ACPI_UINT32_MAX, ACPI_ADR_SPACE_EC); set_bit(EC_FLAGS_EC_REG_CALLED, &ec->flags); } if (!device) return 0; if (ec->gpe < 0) { /* ACPI reduced hardware platforms use a GpioInt from _CRS. */ int irq = acpi_dev_gpio_irq_get(device, 0); /* * Bail out right away for deferred probing or complete the * initialization regardless of any other errors. */ if (irq == -EPROBE_DEFER) return -EPROBE_DEFER; else if (irq >= 0) ec->irq = irq; } if (!test_bit(EC_FLAGS_QUERY_METHODS_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_QUERY_METHODS_INSTALLED, &ec->flags); } if (!test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { bool ready = false; if (ec->gpe >= 0) ready = install_gpe_event_handler(ec); else if (ec->irq >= 0) ready = install_gpio_irq_event_handler(ec); if (ready) { set_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags); acpi_ec_leave_noirq(ec); } /* * Failures to install an event handler are not fatal, because * the EC can be polled for events. */ } /* EC is fully operational, allow queries */ acpi_ec_enable_event(ec); return 0; } static void ec_remove_handlers(struct acpi_ec *ec) { acpi_handle scope_handle = ec == first_ec ? ACPI_ROOT_OBJECT : ec->handle; if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { if (ACPI_FAILURE(acpi_remove_address_space_handler( scope_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_EVENT_HANDLER_INSTALLED, &ec->flags)) { if (ec->gpe >= 0 && ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler))) pr_err("failed to remove gpe handler\n"); if (ec->irq >= 0) free_irq(ec->irq, ec); clear_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags); } if (test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) { acpi_ec_remove_query_handlers(ec, true, 0); clear_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags); } } static int acpi_ec_setup(struct acpi_ec *ec, struct acpi_device *device, bool call_reg) { int ret; /* First EC capable of handling transactions */ if (!first_ec) first_ec = ec; ret = ec_install_handlers(ec, device, call_reg); if (ret) { if (ec == first_ec) first_ec = NULL; return ret; } pr_info("EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", ec->command_addr, ec->data_addr); if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { if (ec->gpe >= 0) pr_info("GPE=0x%x\n", ec->gpe); else pr_info("IRQ=%d\n", ec->irq); } return ret; } static int acpi_ec_add(struct acpi_device *device) { struct acpi_ec *ec; int ret; strscpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); strscpy(acpi_device_class(device), ACPI_EC_CLASS); if (boot_ec && (boot_ec->handle == device->handle || !strcmp(acpi_device_hid(device), ACPI_ECDT_HID))) { /* Fast path: this device corresponds to the boot EC. */ ec = boot_ec; } else { acpi_status status; ec = acpi_ec_alloc(); if (!ec) return -ENOMEM; status = ec_parse_device(device->handle, 0, ec, NULL); if (status != AE_CTRL_TERMINATE) { ret = -EINVAL; goto err; } if (boot_ec && ec->command_addr == boot_ec->command_addr && ec->data_addr == boot_ec->data_addr) { /* * Trust PNP0C09 namespace location rather than ECDT ID. * But trust ECDT GPE rather than _GPE because of ASUS * quirks. So do not change boot_ec->gpe to ec->gpe, * except when the TRUST_DSDT_GPE quirk is set. */ boot_ec->handle = ec->handle; if (EC_FLAGS_TRUST_DSDT_GPE) boot_ec->gpe = ec->gpe; acpi_handle_debug(ec->handle, "duplicated.\n"); acpi_ec_free(ec); ec = boot_ec; } } ret = acpi_ec_setup(ec, device, true); if (ret) goto err; if (ec == boot_ec) acpi_handle_info(boot_ec->handle, "Boot %s EC initialization complete\n", boot_ec_is_ecdt ? "ECDT" : "DSDT"); acpi_handle_info(ec->handle, "EC: Used to handle transactions and events\n"); 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_dev_clear_dependencies(device); acpi_handle_debug(ec->handle, "enumerated.\n"); return 0; err: if (ec != boot_ec) acpi_ec_free(ec); return ret; } static void acpi_ec_remove(struct acpi_device *device) { struct acpi_ec *ec; if (!device) return; 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); } } void acpi_ec_register_opregions(struct acpi_device *adev) { if (first_ec && first_ec->handle != adev->handle) acpi_execute_reg_methods(adev->handle, 1, ACPI_ADR_SPACE_EC); } 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}, {ACPI_ECDT_HID, 0}, {"", 0}, }; /* * This function is not Windows-compatible as Windows never enumerates the * namespace EC before the main ACPI device enumeration process. It is * retained for historical reason and will be deprecated in the future. */ void __init acpi_ec_dsdt_probe(void) { struct acpi_ec *ec; acpi_status status; int ret; /* * If a platform has ECDT, there is no need to proceed as the * following probe is not a part of the ACPI device enumeration, * executing _STA is not safe, and thus this probe may risk of * picking up an invalid EC device. */ if (boot_ec) return; ec = acpi_ec_alloc(); if (!ec) return; /* * 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) { acpi_ec_free(ec); return; } /* * 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_ec_setup(ec, NULL, true); if (ret) { acpi_ec_free(ec); return; } boot_ec = ec; acpi_handle_info(ec->handle, "Boot DSDT EC used to handle transactions\n"); } /* * acpi_ec_ecdt_start - Finalize the boot ECDT EC initialization. * * First, look for an ACPI handle for the boot ECDT EC if acpi_ec_add() has not * found a matching object in the namespace. * * Next, in case the DSDT EC is not functioning, it is still necessary to * provide a functional ECDT EC to handle events, so add an extra device object * to represent it (see https://bugzilla.kernel.org/show_bug.cgi?id=115021). * * This is useful on platforms with valid ECDT and invalid DSDT EC settings, * like ASUS X550ZE (see https://bugzilla.kernel.org/show_bug.cgi?id=196847). */ static void __init acpi_ec_ecdt_start(void) { struct acpi_table_ecdt *ecdt_ptr; acpi_handle handle; acpi_status status; /* Bail out if a matching EC has been found in the namespace. */ if (!boot_ec || boot_ec->handle != ACPI_ROOT_OBJECT) return; /* Look up the object pointed to from the ECDT in the namespace. */ status = acpi_get_table(ACPI_SIG_ECDT, 1, (struct acpi_table_header **)&ecdt_ptr); if (ACPI_FAILURE(status)) return; status = acpi_get_handle(NULL, ecdt_ptr->id, &handle); if (ACPI_SUCCESS(status)) { boot_ec->handle = handle; /* Add a special ACPI device object to represent the boot EC. */ acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC); } acpi_put_table((struct acpi_table_header *)ecdt_ptr); } /* * 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; ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; return 0; } /* * 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; } /* * Some ECDTs contain wrong GPE setting, but they share the same port addresses * with DSDT EC, don't duplicate the DSDT EC with ECDT EC in this case. * https://bugzilla.kernel.org/show_bug.cgi?id=209989 */ static int ec_honor_dsdt_gpe(const struct dmi_system_id *id) { pr_debug("Detected system needing DSDT GPE setting.\n"); EC_FLAGS_TRUST_DSDT_GPE = 1; return 0; } static const struct dmi_system_id ec_dmi_table[] __initconst = { { /* * MSI MS-171F * https://bugzilla.kernel.org/show_bug.cgi?id=12461 */ .callback = ec_correct_ecdt, .matches = { DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"), }, }, { /* * HP Pavilion Gaming Laptop 15-cx0xxx * https://bugzilla.kernel.org/show_bug.cgi?id=209989 */ .callback = ec_honor_dsdt_gpe, .matches = { DMI_MATCH(DMI_SYS_VENDOR, "HP"), DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion Gaming Laptop 15-cx0xxx"), }, }, { /* * HP Pavilion Gaming Laptop 15-cx0041ur */ .callback = ec_honor_dsdt_gpe, .matches = { DMI_MATCH(DMI_SYS_VENDOR, "HP"), DMI_MATCH(DMI_PRODUCT_NAME, "HP 15-cx0041ur"), }, }, { /* * HP Pavilion Gaming Laptop 15-dk1xxx * https://github.com/systemd/systemd/issues/28942 */ .callback = ec_honor_dsdt_gpe, .matches = { DMI_MATCH(DMI_SYS_VENDOR, "HP"), DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion Gaming Laptop 15-dk1xxx"), }, }, { /* * HP 250 G7 Notebook PC */ .callback = ec_honor_dsdt_gpe, .matches = { DMI_MATCH(DMI_SYS_VENDOR, "HP"), DMI_MATCH(DMI_PRODUCT_NAME, "HP 250 G7 Notebook PC"), }, }, { /* * Samsung hardware * https://bugzilla.kernel.org/show_bug.cgi?id=44161 */ .callback = ec_clear_on_resume, .matches = { DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."), }, }, {} }; void __init acpi_ec_ecdt_probe(void) { struct acpi_table_ecdt *ecdt_ptr; struct acpi_ec *ec; acpi_status status; int ret; /* 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)) return; if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) { /* * Asus X50GL: * https://bugzilla.kernel.org/show_bug.cgi?id=11880 */ goto out; } ec = acpi_ec_alloc(); if (!ec) goto out; 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; } /* * Ignore the GPE value on Reduced Hardware platforms. * Some products have this set to an erroneous value. */ if (!acpi_gbl_reduced_hardware) ec->gpe = ecdt_ptr->gpe; ec->handle = ACPI_ROOT_OBJECT; /* * At this point, the namespace is not initialized, so do not find * the namespace objects, or handle the events. */ ret = acpi_ec_setup(ec, NULL, false); if (ret) { acpi_ec_free(ec); goto out; } boot_ec = ec; boot_ec_is_ecdt = true; pr_info("Boot ECDT EC used to handle transactions\n"); out: acpi_put_table((struct acpi_table_header *)ecdt_ptr); } #ifdef CONFIG_PM_SLEEP static int acpi_ec_suspend(struct device *dev) { struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); if (!pm_suspend_no_platform() && ec_freeze_events) acpi_ec_disable_event(ec); return 0; } static int acpi_ec_suspend_noirq(struct device *dev) { struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); /* * The SCI handler doesn't run at this point, so the GPE can be * masked at the low level without side effects. */ if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && ec->gpe >= 0 && ec->reference_count >= 1) acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 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); if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && ec->gpe >= 0 && ec->reference_count >= 1) acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 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; } void acpi_ec_mark_gpe_for_wake(void) { if (first_ec && !ec_no_wakeup) acpi_mark_gpe_for_wake(NULL, first_ec->gpe); } EXPORT_SYMBOL_GPL(acpi_ec_mark_gpe_for_wake); void acpi_ec_set_gpe_wake_mask(u8 action) { if (pm_suspend_no_platform() && first_ec && !ec_no_wakeup) acpi_set_gpe_wake_mask(NULL, first_ec->gpe, action); } static bool acpi_ec_work_in_progress(struct acpi_ec *ec) { return ec->events_in_progress + ec->queries_in_progress > 0; } bool acpi_ec_dispatch_gpe(void) { bool work_in_progress = false; if (!first_ec) return acpi_any_gpe_status_set(U32_MAX); /* * Report wakeup if the status bit is set for any enabled GPE other * than the EC one. */ if (acpi_any_gpe_status_set(first_ec->gpe)) return true; /* * Cancel the SCI wakeup and process all pending events in case there * are any wakeup ones in there. * * Note that if any non-EC GPEs are active at this point, the SCI will * retrigger after the rearming in acpi_s2idle_wake(), so no events * should be missed by canceling the wakeup here. */ pm_system_cancel_wakeup(); /* * Dispatch the EC GPE in-band, but do not report wakeup in any case * to allow the caller to process events properly after that. */ spin_lock_irq(&first_ec->lock); if (acpi_ec_gpe_status_set(first_ec)) { pm_pr_dbg("ACPI EC GPE status set\n"); clear_gpe_and_advance_transaction(first_ec, false); work_in_progress = acpi_ec_work_in_progress(first_ec); } spin_unlock_irq(&first_ec->lock); if (!work_in_progress) return false; pm_pr_dbg("ACPI EC GPE dispatched\n"); /* Drain EC work. */ do { acpi_ec_flush_work(); pm_pr_dbg("ACPI EC work flushed\n"); spin_lock_irq(&first_ec->lock); work_in_progress = acpi_ec_work_in_progress(first_ec); spin_unlock_irq(&first_ec->lock); } while (work_in_progress && !pm_wakeup_pending()); return false; } #endif /* CONFIG_PM_SLEEP */ 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, const 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, const struct kernel_param *kp) { switch (ec_event_clearing) { case ACPI_EC_EVT_TIMING_STATUS: return sprintf(buffer, "status\n"); case ACPI_EC_EVT_TIMING_QUERY: return sprintf(buffer, "query\n"); case ACPI_EC_EVT_TIMING_EVENT: return sprintf(buffer, "event\n"); default: return sprintf(buffer, "invalid\n"); } 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 void acpi_ec_destroy_workqueues(void) { if (ec_wq) { destroy_workqueue(ec_wq); ec_wq = NULL; } if (ec_query_wq) { destroy_workqueue(ec_query_wq); ec_query_wq = NULL; } } static int acpi_ec_init_workqueues(void) { if (!ec_wq) ec_wq = alloc_ordered_workqueue("kec", 0); if (!ec_query_wq) ec_query_wq = alloc_workqueue("kec_query", 0, ec_max_queries); if (!ec_wq || !ec_query_wq) { acpi_ec_destroy_workqueues(); return -ENODEV; } return 0; } static const struct dmi_system_id acpi_ec_no_wakeup[] = { { .matches = { DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), DMI_MATCH(DMI_PRODUCT_FAMILY, "Thinkpad X1 Carbon 6th"), }, }, { .matches = { DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Yoga 3rd"), }, }, { .matches = { DMI_MATCH(DMI_SYS_VENDOR, "HP"), DMI_MATCH(DMI_PRODUCT_FAMILY, "103C_5336AN HP ZHAN 66 Pro"), }, }, { }, }; void __init acpi_ec_init(void) { int result; result = acpi_ec_init_workqueues(); if (result) return; /* * Disable EC wakeup on following systems to prevent periodic * wakeup from EC GPE. */ if (dmi_check_system(acpi_ec_no_wakeup)) { ec_no_wakeup = true; pr_debug("Disabling EC wakeup on suspend-to-idle\n"); } /* Driver must be registered after acpi_ec_init_workqueues(). */ acpi_bus_register_driver(&acpi_ec_driver); acpi_ec_ecdt_start(); } /* EC driver currently not unloadable */ #if 0 static void __exit acpi_ec_exit(void) { acpi_bus_unregister_driver(&acpi_ec_driver); acpi_ec_destroy_workqueues(); } #endif /* 0 */