#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
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;
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 */
!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;
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++;
}
}
+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);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static bool acpi_ec_query_flushed(struct acpi_ec *ec)
+{
+ bool flushed;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ec->lock, flags);
+ flushed = !ec->nr_pending_queries;
+ spin_unlock_irqrestore(&ec->lock, flags);
+ return flushed;
+}
+
+static void __acpi_ec_flush_event(struct acpi_ec *ec)
+{
+ /*
+ * When ec_freeze_events is true, we need to flush events in
+ * the proper position before entering the noirq stage.
+ */
+ wait_event(ec->wait, acpi_ec_query_flushed(ec));
+ if (ec_query_wq)
+ flush_workqueue(ec_query_wq);
+}
+
+static void acpi_ec_disable_event(struct acpi_ec *ec)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&ec->lock, flags);
+ __acpi_ec_disable_event(ec);
+ spin_unlock_irqrestore(&ec->lock, flags);
+ __acpi_ec_flush_event(ec);
+}
+#endif /* CONFIG_PM_SLEEP */
+
static bool acpi_ec_guard_event(struct acpi_ec *ec)
{
bool guarded = true;
static int ec_guard(struct acpi_ec *ec)
{
- unsigned long guard = usecs_to_jiffies(ec_polling_guard);
+ 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) {
+ if (ec->busy_polling) {
/* Perform busy polling */
if (ec_transaction_completed(ec))
return 0;
}
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;
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;
}
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
if (function != ACPI_READ && function != ACPI_WRITE)
return AE_BAD_PARAMETER;
- if (ec_busy_polling || bits > 8)
+ if (ec->busy_polling || bits > 8)
acpi_ec_burst_enable(ec);
for (i = 0; i < bytes; ++i, ++address, ++value)
acpi_ec_read(ec, address, value) :
acpi_ec_write(ec, address, *value);
- if (ec_busy_polling || bits > 8)
+ if (ec->busy_polling || bits > 8)
acpi_ec_burst_disable(ec);
switch (result) {
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);
spin_lock_init(&ec->lock);
INIT_WORK(&ec->work, acpi_ec_event_handler);
ec->timestamp = jiffies;
+ ec->busy_polling = true;
+ ec->polling_guard = 0;
return ec;
}
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;
acpi_ec_start(ec, false);
if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) {
+ acpi_ec_enter_noirq(ec);
status = acpi_install_address_space_handler(ec->handle,
ACPI_ADR_SPACE_EC,
&acpi_ec_space_handler,
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,
/* This is not fatal as we can poll EC events */
if (ACPI_SUCCESS(status)) {
set_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags);
+ acpi_ec_leave_noirq(ec);
if (test_bit(EC_FLAGS_STARTED, &ec->flags) &&
ec->reference_count >= 1)
acpi_ec_enable_gpe(ec, true);
+
+ /* EC is fully operational, allow queries */
+ acpi_ec_enable_event(ec);
}
}
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)
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");
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;
}
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;
}
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);
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
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;
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 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;
.add = acpi_ec_add,
.remove = acpi_ec_remove,
},
+ .drv.pm = &acpi_ec_pm,
};
static inline int acpi_ec_query_init(void)