diff options
Diffstat (limited to 'drivers/acpi/ec.c')
-rw-r--r-- | drivers/acpi/ec.c | 468 |
1 files changed, 379 insertions, 89 deletions
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index e7bd57cc550a..680531062160 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -104,10 +104,12 @@ enum ec_command { #define ACPI_EC_MAX_QUERIES 16 /* Maximum number of parallel queries */ enum { + EC_FLAGS_QUERY_ENABLED, /* Query is enabled */ EC_FLAGS_QUERY_PENDING, /* Query is pending */ EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */ EC_FLAGS_GPE_HANDLER_INSTALLED, /* GPE handler installed */ EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */ + EC_FLAGS_EVT_HANDLER_INSTALLED, /* _Qxx handlers installed */ EC_FLAGS_STARTED, /* Driver is started */ EC_FLAGS_STOPPED, /* Driver is stopped */ EC_FLAGS_COMMAND_STORM, /* GPE storms occurred to the @@ -145,6 +147,10 @@ static unsigned int ec_storm_threshold __read_mostly = 8; module_param(ec_storm_threshold, uint, 0644); MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm"); +static bool ec_freeze_events __read_mostly = true; +module_param(ec_freeze_events, bool, 0644); +MODULE_PARM_DESC(ec_freeze_events, "Disabling event handling during suspend/resume"); + struct acpi_ec_query_handler { struct list_head node; acpi_ec_query_func func; @@ -179,6 +185,7 @@ static void acpi_ec_event_processor(struct work_struct *work); struct acpi_ec *boot_ec, *first_ec; EXPORT_SYMBOL(first_ec); +static bool boot_ec_is_ecdt = false; static struct workqueue_struct *ec_query_wq; static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ @@ -239,6 +246,30 @@ static bool acpi_ec_started(struct acpi_ec *ec) !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; @@ -429,7 +460,8 @@ 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)) { + if (acpi_ec_event_enabled(ec) && + !test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { ec_dbg_evt("Command(%s) submitted/blocked", acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); ec->nr_pending_queries++; @@ -446,6 +478,86 @@ static void acpi_ec_complete_query(struct acpi_ec *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"); + if (!test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) + advance_transaction(ec); +} + +static inline void __acpi_ec_disable_event(struct acpi_ec *ec) +{ + if (test_and_clear_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) + ec_log_drv("event blocked"); +} + +/* + * Process _Q events that might have accumulated in the EC. + * Run with locked ec mutex. + */ +static void acpi_ec_clear(struct acpi_ec *ec) +{ + int i, status; + u8 value = 0; + + for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) { + status = acpi_ec_query(ec, &value); + if (status || !value) + break; + } + if (unlikely(i == ACPI_EC_CLEAR_MAX)) + pr_warn("Warning: Maximum of %d stale EC events cleared\n", i); + else + pr_info("%d stale EC events cleared\n", i); +} + +static void acpi_ec_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); +} + +static bool acpi_ec_query_flushed(struct acpi_ec *ec) +{ + bool flushed; + unsigned long flags; + + spin_lock_irqsave(&ec->lock, flags); + flushed = !ec->nr_pending_queries; + spin_unlock_irqrestore(&ec->lock, flags); + return flushed; +} + +static void __acpi_ec_flush_event(struct acpi_ec *ec) +{ + /* + * When ec_freeze_events is true, we need to flush events in + * the proper position before entering the noirq stage. + */ + wait_event(ec->wait, acpi_ec_query_flushed(ec)); + if (ec_query_wq) + flush_workqueue(ec_query_wq); +} + +static void acpi_ec_disable_event(struct acpi_ec *ec) +{ + unsigned long flags; + + spin_lock_irqsave(&ec->lock, flags); + __acpi_ec_disable_event(ec); + spin_unlock_irqrestore(&ec->lock, flags); + __acpi_ec_flush_event(ec); +} + static bool acpi_ec_guard_event(struct acpi_ec *ec) { bool guarded = true; @@ -832,27 +944,6 @@ acpi_handle ec_get_handle(void) } EXPORT_SYMBOL(ec_get_handle); -/* - * Process _Q events that might have accumulated in the EC. - * Run with locked ec mutex. - */ -static void acpi_ec_clear(struct acpi_ec *ec) -{ - int i, status; - u8 value = 0; - - for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) { - status = acpi_ec_query(ec, &value); - if (status || !value) - break; - } - - if (unlikely(i == ACPI_EC_CLEAR_MAX)) - pr_warn("Warning: Maximum of %d stale EC events cleared\n", i); - else - pr_info("%d stale EC events cleared\n", i); -} - static void acpi_ec_start(struct acpi_ec *ec, bool resuming) { unsigned long flags; @@ -896,7 +987,8 @@ static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 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"); @@ -919,20 +1011,6 @@ void acpi_ec_block_transactions(void) void acpi_ec_unblock_transactions(void) { - struct acpi_ec *ec = first_ec; - - if (!ec) - return; - - /* Allow transactions to be carried out again */ - acpi_ec_start(ec, true); - - if (EC_FLAGS_CLEAR_ON_RESUME) - acpi_ec_clear(ec); -} - -void acpi_ec_unblock_transactions_early(void) -{ /* * Allow transactions to happen again (this function is called from * atomic context during wakeup, so we don't need to acquire the mutex). @@ -1228,13 +1306,21 @@ acpi_ec_space_handler(u32 function, acpi_physical_address address, static acpi_status ec_parse_io_ports(struct acpi_resource *resource, void *context); -static struct acpi_ec *make_acpi_ec(void) +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; - ec->flags = 1 << EC_FLAGS_QUERY_PENDING; mutex_init(&ec->mutex); init_waitqueue_head(&ec->wait); INIT_LIST_HEAD(&ec->list); @@ -1290,7 +1376,12 @@ ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) return AE_CTRL_TERMINATE; } -static int ec_install_handlers(struct acpi_ec *ec) +/* + * Note: This function returns an error code only when the address space + * handler is not installed, which means "not able to handle + * transactions". + */ +static int ec_install_handlers(struct acpi_ec *ec, bool handle_events) { acpi_status status; @@ -1319,6 +1410,16 @@ static int ec_install_handlers(struct acpi_ec *ec) set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); } + if (!handle_events) + return 0; + + if (!test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) { + /* Find and register all query methods */ + acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, + acpi_ec_register_query_methods, + NULL, ec, NULL); + set_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags); + } if (!test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) { status = acpi_install_gpe_raw_handler(NULL, ec->gpe, ACPI_GPE_EDGE_TRIGGERED, @@ -1329,6 +1430,9 @@ static int ec_install_handlers(struct acpi_ec *ec) if (test_bit(EC_FLAGS_STARTED, &ec->flags) && ec->reference_count >= 1) acpi_ec_enable_gpe(ec, true); + + /* EC is fully operational, allow queries */ + acpi_ec_enable_event(ec); } } @@ -1363,23 +1467,104 @@ static void ec_remove_handlers(struct acpi_ec *ec) pr_err("failed to remove gpe handler\n"); clear_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags); } + if (test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) { + acpi_ec_remove_query_handlers(ec, true, 0); + clear_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags); + } } -static struct acpi_ec *acpi_ec_alloc(void) +static int acpi_ec_setup(struct acpi_ec *ec, bool handle_events) { - struct acpi_ec *ec; + int ret; - /* Check for boot EC */ - if (boot_ec) { - ec = boot_ec; - boot_ec = NULL; - ec_remove_handlers(ec); - if (first_ec == ec) - first_ec = NULL; - } else { - ec = make_acpi_ec(); + ret = ec_install_handlers(ec, handle_events); + if (ret) + return ret; + + /* First EC capable of handling transactions */ + if (!first_ec) { + first_ec = ec; + acpi_handle_info(first_ec->handle, "Used as first EC\n"); } - return ec; + + acpi_handle_info(ec->handle, + "GPE=0x%lx, EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", + ec->gpe, ec->command_addr, ec->data_addr); + return ret; +} + +static int acpi_config_boot_ec(struct acpi_ec *ec, acpi_handle handle, + bool handle_events, bool is_ecdt) +{ + int ret; + + /* + * Changing the ACPI handle results in a re-configuration of the + * boot EC. And if it happens after the namespace initialization, + * it causes _REG evaluations. + */ + if (boot_ec && boot_ec->handle != handle) + ec_remove_handlers(boot_ec); + + /* Unset old boot EC */ + if (boot_ec != ec) + acpi_ec_free(boot_ec); + + /* + * ECDT device creation is split into acpi_ec_ecdt_probe() and + * acpi_ec_ecdt_start(). This function takes care of completing the + * ECDT parsing logic as the handle update should be performed + * between the installation/uninstallation of the handlers. + */ + if (ec->handle != handle) + ec->handle = handle; + + ret = acpi_ec_setup(ec, handle_events); + if (ret) + return ret; + + /* Set new boot EC */ + if (!boot_ec) { + boot_ec = ec; + boot_ec_is_ecdt = is_ecdt; + } + + acpi_handle_info(boot_ec->handle, + "Used as boot %s EC to handle transactions%s\n", + is_ecdt ? "ECDT" : "DSDT", + handle_events ? " and events" : ""); + return ret; +} + +static bool acpi_ec_ecdt_get_handle(acpi_handle *phandle) +{ + struct acpi_table_ecdt *ecdt_ptr; + acpi_status status; + acpi_handle handle; + + status = acpi_get_table(ACPI_SIG_ECDT, 1, + (struct acpi_table_header **)&ecdt_ptr); + if (ACPI_FAILURE(status)) + return false; + + status = acpi_get_handle(NULL, ecdt_ptr->id, &handle); + if (ACPI_FAILURE(status)) + return false; + + *phandle = handle; + return true; +} + +static bool acpi_is_boot_ec(struct acpi_ec *ec) +{ + if (!boot_ec) + return false; + if (ec->handle == boot_ec->handle && + ec->gpe == boot_ec->gpe && + ec->command_addr == boot_ec->command_addr && + ec->data_addr == boot_ec->data_addr) + return true; + return false; } static int acpi_ec_add(struct acpi_device *device) @@ -1395,16 +1580,21 @@ static int acpi_ec_add(struct acpi_device *device) return -ENOMEM; if (ec_parse_device(device->handle, 0, ec, NULL) != AE_CTRL_TERMINATE) { - kfree(ec); - return -EINVAL; + ret = -EINVAL; + goto err_alloc; } - /* Find and register all query methods */ - acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, - acpi_ec_register_query_methods, NULL, ec, NULL); + if (acpi_is_boot_ec(ec)) { + boot_ec_is_ecdt = false; + acpi_handle_debug(ec->handle, "duplicated.\n"); + acpi_ec_free(ec); + ec = boot_ec; + ret = acpi_config_boot_ec(ec, ec->handle, true, false); + } else + ret = acpi_ec_setup(ec, true); + if (ret) + goto err_query; - if (!first_ec) - first_ec = ec; device->driver_data = ec; ret = !!request_region(ec->data_addr, 1, "EC data"); @@ -1412,20 +1602,17 @@ static int acpi_ec_add(struct acpi_device *device) ret = !!request_region(ec->command_addr, 1, "EC cmd"); WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); - pr_info("GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n", - ec->gpe, ec->command_addr, ec->data_addr); - - ret = ec_install_handlers(ec); - /* Reprobe devices depending on the EC */ acpi_walk_dep_device_list(ec->handle); + acpi_handle_debug(ec->handle, "enumerated.\n"); + return 0; - /* EC is fully operational, allow queries */ - clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); - - /* Clear stale _Q events if hardware might require that */ - if (EC_FLAGS_CLEAR_ON_RESUME) - acpi_ec_clear(ec); +err_query: + if (ec != boot_ec) + acpi_ec_remove_query_handlers(ec, true, 0); +err_alloc: + if (ec != boot_ec) + acpi_ec_free(ec); return ret; } @@ -1437,14 +1624,13 @@ static int acpi_ec_remove(struct acpi_device *device) return -EINVAL; ec = acpi_driver_data(device); - ec_remove_handlers(ec); - acpi_ec_remove_query_handlers(ec, true, 0); release_region(ec->data_addr, 1); release_region(ec->command_addr, 1); device->driver_data = NULL; - if (ec == first_ec) - first_ec = NULL; - kfree(ec); + if (ec != boot_ec) { + ec_remove_handlers(ec); + acpi_ec_free(ec); + } return 0; } @@ -1486,9 +1672,8 @@ int __init acpi_ec_dsdt_probe(void) if (!ec) return -ENOMEM; /* - * Finding EC from DSDT if there is no ECDT EC available. When this - * function is invoked, ACPI tables have been fully loaded, we can - * walk namespace now. + * 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); @@ -1496,16 +1681,47 @@ int __init acpi_ec_dsdt_probe(void) ret = -ENODEV; goto error; } - ret = ec_install_handlers(ec); - + /* + * When the DSDT EC is available, always re-configure boot EC to + * have _REG evaluated. _REG can only be evaluated after the + * namespace initialization. + * At this point, the GPE is not fully initialized, so do not to + * handle the events. + */ + ret = acpi_config_boot_ec(ec, ec->handle, false, false); error: if (ret) - kfree(ec); - else - first_ec = boot_ec = ec; + acpi_ec_free(ec); return ret; } +/* + * If the DSDT EC is not functioning, we still need to prepare a fully + * functioning ECDT EC first in order to handle the events. + * https://bugzilla.kernel.org/show_bug.cgi?id=115021 + */ +int __init acpi_ec_ecdt_start(void) +{ + acpi_handle handle; + + if (!boot_ec) + return -ENODEV; + /* + * The DSDT EC should have already been started in + * acpi_ec_add(). + */ + if (!boot_ec_is_ecdt) + return -ENODEV; + + /* + * At this point, the namespace and the GPE is initialized, so + * start to find the namespace objects and handle the events. + */ + if (!acpi_ec_ecdt_get_handle(&handle)) + return -ENODEV; + return acpi_config_boot_ec(boot_ec, handle, true, true); +} + #if 0 /* * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not @@ -1600,7 +1816,6 @@ int __init acpi_ec_ecdt_probe(void) goto error; } - pr_info("EC description table is found, configuring boot EC\n"); if (EC_FLAGS_CORRECT_ECDT) { ec->command_addr = ecdt_ptr->data.address; ec->data_addr = ecdt_ptr->control.address; @@ -1609,16 +1824,90 @@ int __init acpi_ec_ecdt_probe(void) ec->data_addr = ecdt_ptr->data.address; } ec->gpe = ecdt_ptr->gpe; - ec->handle = ACPI_ROOT_OBJECT; - ret = ec_install_handlers(ec); + + /* + * At this point, the namespace is not initialized, so do not find + * the namespace objects, or handle the events. + */ + ret = acpi_config_boot_ec(ec, ACPI_ROOT_OBJECT, false, true); error: if (ret) - kfree(ec); - else - first_ec = boot_ec = ec; + acpi_ec_free(ec); return ret; } +#ifdef CONFIG_PM_SLEEP +static void acpi_ec_enter_noirq(struct acpi_ec *ec) +{ + unsigned long flags; + + if (ec == first_ec) { + spin_lock_irqsave(&ec->lock, flags); + ec->saved_busy_polling = ec_busy_polling; + ec->saved_polling_guard = ec_polling_guard; + 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; + + if (ec == first_ec) { + spin_lock_irqsave(&ec->lock, flags); + ec_busy_polling = ec->saved_busy_polling; + ec_polling_guard = ec->saved_polling_guard; + ec_log_drv("interrupt unblocked"); + spin_unlock_irqrestore(&ec->lock, flags); + } +} + +static int acpi_ec_suspend_noirq(struct device *dev) +{ + struct acpi_ec *ec = + acpi_driver_data(to_acpi_device(dev)); + + acpi_ec_enter_noirq(ec); + return 0; +} + +static int acpi_ec_resume_noirq(struct device *dev) +{ + struct acpi_ec *ec = + acpi_driver_data(to_acpi_device(dev)); + + acpi_ec_leave_noirq(ec); + return 0; +} + +static int acpi_ec_suspend(struct device *dev) +{ + struct acpi_ec *ec = + acpi_driver_data(to_acpi_device(dev)); + + if (ec_freeze_events) + acpi_ec_disable_event(ec); + return 0; +} + +static int acpi_ec_resume(struct device *dev) +{ + struct acpi_ec *ec = + acpi_driver_data(to_acpi_device(dev)); + + acpi_ec_enable_event(ec); + return 0; +} +#endif + +static const struct dev_pm_ops acpi_ec_pm = { + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq) + SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume) +}; + static int param_set_event_clearing(const char *val, struct kernel_param *kp) { int result = 0; @@ -1664,6 +1953,7 @@ static struct acpi_driver acpi_ec_driver = { .add = acpi_ec_add, .remove = acpi_ec_remove, }, + .drv.pm = &acpi_ec_pm, }; static inline int acpi_ec_query_init(void) |