From e5fd91f1ef340da553f7a79da9540c3db711c937 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Tue, 8 Sep 2015 01:01:14 -0300 Subject: Linux-libre 4.2-gnu --- drivers/acpi/ec.c | 357 ++++++++++++++++++++++++++++++++++++++---------------- 1 file changed, 254 insertions(+), 103 deletions(-) (limited to 'drivers/acpi/ec.c') diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index 5e8fed448..9d4761d2f 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -59,6 +59,38 @@ #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, @@ -70,13 +102,13 @@ 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_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 */ enum { EC_FLAGS_QUERY_PENDING, /* Query is pending */ + EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */ EC_FLAGS_HANDLERS_INSTALLED, /* Handlers for GPE and * OpReg are installed */ EC_FLAGS_STARTED, /* Driver is started */ @@ -93,6 +125,16 @@ 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 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 @@ -121,7 +163,6 @@ struct transaction { u8 wlen; u8 rlen; u8 flags; - unsigned long timestamp; }; static int acpi_ec_query(struct acpi_ec *ec, u8 *data); @@ -130,7 +171,6 @@ static void advance_transaction(struct acpi_ec *ec); struct acpi_ec *boot_ec, *first_ec; EXPORT_SYMBOL(first_ec); -static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */ static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */ static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */ static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ @@ -218,7 +258,7 @@ static inline u8 acpi_ec_read_data(struct acpi_ec *ec) { u8 x = inb(ec->data_addr); - ec->curr->timestamp = jiffies; + ec->timestamp = jiffies; ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x); return x; } @@ -227,14 +267,14 @@ static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command) { ec_dbg_raw("EC_SC(W) = 0x%2.2x", command); outb(command, ec->command_addr); - ec->curr->timestamp = jiffies; + 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->curr->timestamp = jiffies; + ec->timestamp = jiffies; } #ifdef DEBUG @@ -267,7 +307,7 @@ 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; + return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false; } static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) @@ -379,19 +419,49 @@ static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec) static void acpi_ec_submit_query(struct acpi_ec *ec) { if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { - ec_dbg_req("Event started"); + 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 (ec->curr->command == ACPI_EC_COMMAND_QUERY) { + if (test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); - ec_dbg_req("Event stopped"); + ec_dbg_evt("Command(%s) unblocked", + acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); } } +static bool acpi_ec_guard_event(struct acpi_ec *ec) +{ + 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)) + return false; + + /* + * Postpone the query submission to allow the firmware to proceed, + * we shouldn't check SCI_EVT before the firmware reflagging it. + */ + return true; +} + +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; @@ -404,6 +474,22 @@ static int ec_transaction_completed(struct acpi_ec *ec) 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; @@ -420,6 +506,18 @@ static void advance_transaction(struct acpi_ec *ec) 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) { @@ -432,17 +530,17 @@ static void advance_transaction(struct acpi_ec *ec) if ((status & ACPI_EC_FLAG_OBF) == 1) { t->rdata[t->ri++] = acpi_ec_read_data(ec); if (t->rlen == t->ri) { - t->flags |= ACPI_EC_COMMAND_COMPLETE; + ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); if (t->command == ACPI_EC_COMMAND_QUERY) - ec_dbg_req("Command(%s) hardware completion", - acpi_ec_cmd_string(t->command)); + 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) { - t->flags |= ACPI_EC_COMMAND_COMPLETE; + ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); wakeup = true; } goto out; @@ -450,17 +548,15 @@ static void advance_transaction(struct acpi_ec *ec) if (EC_FLAGS_QUERY_HANDSHAKE && !(status & ACPI_EC_FLAG_SCI) && (t->command == ACPI_EC_COMMAND_QUERY)) { - t->flags |= ACPI_EC_COMMAND_POLL; - acpi_ec_complete_query(ec); + ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); t->rdata[t->ri++] = 0x00; - t->flags |= ACPI_EC_COMMAND_COMPLETE; - ec_dbg_req("Command(%s) software completion", - acpi_ec_cmd_string(t->command)); + 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); - t->flags |= ACPI_EC_COMMAND_POLL; - acpi_ec_complete_query(ec); + ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); } else goto err; goto out; @@ -490,8 +586,39 @@ static void start_transaction(struct acpi_ec *ec) { ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0; ec->curr->flags = 0; - ec->curr->timestamp = jiffies; - advance_transaction(ec); +} + +static int ec_guard(struct acpi_ec *ec) +{ + unsigned long guard = usecs_to_jiffies(ec_polling_guard); + unsigned long timeout = ec->timestamp + guard; + + do { + if (ec_busy_polling) { + /* Perform busy polling */ + if (ec_transaction_completed(ec)) + return 0; + udelay(jiffies_to_usecs(guard)); + } else { + /* + * Perform wait polling + * + * For SCI_EVT clearing timing of "event", + * performing guarding before re-checking the + * SCI_EVT. Otherwise, such guarding is not needed + * due to the old practices. + */ + if (!ec_transaction_polled(ec) && + !acpi_ec_guard_event(ec)) + break; + if (wait_event_timeout(ec->wait, + ec_transaction_completed(ec), + guard)) + return 0; + } + /* Guard the register accesses for the polling modes */ + } while (time_before(jiffies, timeout)); + return -ETIME; } static int ec_poll(struct acpi_ec *ec) @@ -502,25 +629,11 @@ 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()) { - usecs = ACPI_EC_MSI_UDELAY; - udelay(usecs); - if (ec_transaction_completed(ec)) - return 0; - } else { - if (wait_event_timeout(ec->wait, - ec_transaction_completed(ec), - usecs_to_jiffies(usecs))) - return 0; - } + if (!ec_guard(ec)) + return 0; spin_lock_irqsave(&ec->lock, flags); - if (time_after(jiffies, - ec->curr->timestamp + - usecs_to_jiffies(usecs))) - advance_transaction(ec); + advance_transaction(ec); spin_unlock_irqrestore(&ec->lock, flags); } while (time_before(jiffies, delay)); pr_debug("controller reset, restart transaction\n"); @@ -537,8 +650,6 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, unsigned long tmp; int ret = 0; - if (EC_FLAGS_MSI) - udelay(ACPI_EC_MSI_UDELAY); /* start transaction */ spin_lock_irqsave(&ec->lock, tmp); /* Enable GPE for command processing (IBF=0/OBF=1) */ @@ -552,7 +663,9 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 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); @@ -575,6 +688,7 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 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); @@ -586,8 +700,6 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) status = acpi_ec_transaction_unlocked(ec, t); - if (test_bit(EC_FLAGS_COMMAND_STORM, &ec->flags)) - msleep(1); if (ec->global_lock) acpi_release_global_lock(glk); unlock: @@ -923,11 +1035,54 @@ static int acpi_ec_query(struct acpi_ec *ec, u8 *data) return result; } -static void acpi_ec_gpe_poller(struct work_struct *work) +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); - acpi_ec_query(ec, NULL); + 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, @@ -961,7 +1116,7 @@ acpi_ec_space_handler(u32 function, acpi_physical_address address, if (function != ACPI_READ && function != ACPI_WRITE) return AE_BAD_PARAMETER; - if (EC_FLAGS_MSI || bits > 8) + if (ec_busy_polling || bits > 8) acpi_ec_burst_enable(ec); for (i = 0; i < bytes; ++i, ++address, ++value) @@ -969,7 +1124,7 @@ acpi_ec_space_handler(u32 function, acpi_physical_address address, acpi_ec_read(ec, address, value) : acpi_ec_write(ec, address, *value); - if (EC_FLAGS_MSI || bits > 8) + if (ec_busy_polling || bits > 8) acpi_ec_burst_disable(ec); switch (result) { @@ -1002,7 +1157,8 @@ static struct acpi_ec *make_acpi_ec(void) init_waitqueue_head(&ec->wait); INIT_LIST_HEAD(&ec->list); spin_lock_init(&ec->lock); - INIT_WORK(&ec->work, acpi_ec_gpe_poller); + INIT_WORK(&ec->work, acpi_ec_event_handler); + ec->timestamp = jiffies; return ec; } @@ -1237,30 +1393,13 @@ static int ec_validate_ecdt(const struct dmi_system_id *id) return 0; } -/* MSI EC needs special treatment, enable it */ -static int ec_flag_msi(const struct dmi_system_id *id) -{ - pr_debug("Detected MSI hardware, enabling workarounds.\n"); - EC_FLAGS_MSI = 1; - EC_FLAGS_VALIDATE_ECDT = 1; - return 0; -} - -/* - * Clevo M720 notebook actually works ok with IRQ mode, if we lifted - * the GPE storm threshold back to 20 - */ -static int ec_enlarge_storm_threshold(const struct dmi_system_id *id) -{ - pr_debug("Setting the EC GPE storm threshold to 20\n"); - ec_storm_threshold = 20; - return 0; -} - +#if 0 /* - * Acer EC firmware refuses to respond QR_EC when SCI_EVT is not set, for - * which case, we complete the QR_EC without issuing it to the firmware. - * https://bugzilla.kernel.org/show_bug.cgi?id=86211 + * 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) { @@ -1268,6 +1407,7 @@ static int ec_flag_query_handshake(const struct dmi_system_id *id) EC_FLAGS_QUERY_HANDSHAKE = 1; return 0; } +#endif /* * On some hardware it is necessary to clear events accumulated by the EC during @@ -1290,6 +1430,7 @@ 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; } @@ -1299,29 +1440,9 @@ static struct dmi_system_id ec_dmi_table[] __initdata = { DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"), DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL}, { - ec_flag_msi, "MSI hardware", { - DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL}, - { - ec_flag_msi, "MSI hardware", { - DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL}, - { - ec_flag_msi, "MSI hardware", { - DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL}, - { - ec_flag_msi, "MSI hardware", { - DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-STAR")}, NULL}, - { - ec_flag_msi, "Quanta hardware", { - DMI_MATCH(DMI_SYS_VENDOR, "Quanta"), - DMI_MATCH(DMI_PRODUCT_NAME, "TW8/SW8/DW8"),}, NULL}, - { - ec_flag_msi, "Quanta hardware", { - DMI_MATCH(DMI_SYS_VENDOR, "Quanta"), - DMI_MATCH(DMI_PRODUCT_NAME, "TW9/SW9"),}, NULL}, - { - ec_flag_msi, "Clevo W350etq", { - DMI_MATCH(DMI_SYS_VENDOR, "CLEVO CO."), - DMI_MATCH(DMI_PRODUCT_NAME, "W35_37ET"),}, NULL}, + ec_validate_ecdt, "MSI MS-171F", { + DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), + DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL}, { ec_validate_ecdt, "ASUS hardware", { DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL}, @@ -1329,10 +1450,6 @@ static struct dmi_system_id ec_dmi_table[] __initdata = { ec_validate_ecdt, "ASUS hardware", { DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL}, { - ec_enlarge_storm_threshold, "CLEVO hardware", { - DMI_MATCH(DMI_SYS_VENDOR, "CLEVO Co."), - DMI_MATCH(DMI_PRODUCT_NAME, "M720T/M730T"),}, NULL}, - { ec_skip_dsdt_scan, "HP Folio 13", { DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13"),}, NULL}, @@ -1343,9 +1460,6 @@ static struct dmi_system_id ec_dmi_table[] __initdata = { { ec_clear_on_resume, "Samsung hardware", { DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL}, - { - ec_flag_query_handshake, "Acer hardware", { - DMI_MATCH(DMI_SYS_VENDOR, "Acer"), }, NULL}, {}, }; @@ -1427,6 +1541,43 @@ error: return -ENODEV; } +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, -- cgit v1.2.3-54-g00ecf