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Diffstat (limited to 'drivers/acpi/ec.c')
-rw-r--r--drivers/acpi/ec.c117
1 files changed, 75 insertions, 42 deletions
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 42c66b64c12c..b420fb46669d 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -441,17 +441,31 @@ static void acpi_ec_complete_query(struct acpi_ec *ec)
static bool acpi_ec_guard_event(struct acpi_ec *ec)
{
+ bool guarded = true;
+ unsigned long flags;
+
+ 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 begins when EC_FLAGS_QUERY_PENDING is
+ * flagged, which means SCI_EVT check has just been performed.
+ * But if the current transaction is ACPI_EC_COMMAND_QUERY, the
+ * guarding should have already been performed (via
+ * EC_FLAGS_QUERY_GUARDING) and should not be applied so that the
+ * ACPI_EC_COMMAND_QUERY transaction can be transitioned into
+ * ACPI_EC_COMMAND_POLL state immediately.
+ */
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;
+ guarded = false;
+ spin_unlock_irqrestore(&ec->lock, flags);
+ return guarded;
}
static int ec_transaction_polled(struct acpi_ec *ec)
@@ -597,6 +611,7 @@ 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 */
@@ -606,11 +621,13 @@ static int ec_guard(struct acpi_ec *ec)
} 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.
+ * 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))
@@ -620,7 +637,6 @@ static int ec_guard(struct acpi_ec *ec)
guard))
return 0;
}
- /* Guard the register accesses for the polling modes */
} while (time_before(jiffies, timeout));
return -ETIME;
}
@@ -929,6 +945,23 @@ acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler)
return handler;
}
+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;
+ bool found = false;
+
+ mutex_lock(&ec->mutex);
+ list_for_each_entry(handler, &ec->list, node) {
+ if (value == handler->query_bit) {
+ found = true;
+ break;
+ }
+ }
+ mutex_unlock(&ec->mutex);
+ return found ? acpi_ec_get_query_handler(handler) : NULL;
+}
+
static void acpi_ec_query_handler_release(struct kref *kref)
{
struct acpi_ec_query_handler *handler =
@@ -964,14 +997,15 @@ int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
}
EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
-void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
+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) {
- if (query_bit == handler->query_bit) {
+ if (remove_all || query_bit == handler->query_bit) {
list_del_init(&handler->node);
list_add(&handler->node, &free_list);
}
@@ -980,6 +1014,11 @@ void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
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);
+}
EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
static struct acpi_ec_query *acpi_ec_create_query(u8 *pval)
@@ -1025,7 +1064,6 @@ static int acpi_ec_query(struct acpi_ec *ec, u8 *data)
{
u8 value = 0;
int result;
- struct acpi_ec_query_handler *handler;
struct acpi_ec_query *q;
q = acpi_ec_create_query(&value);
@@ -1043,28 +1081,29 @@ static int acpi_ec_query(struct acpi_ec *ec, u8 *data)
if (result)
goto err_exit;
- mutex_lock(&ec->mutex);
- result = -ENODATA;
- list_for_each_entry(handler, &ec->list, node) {
- if (value == handler->query_bit) {
- result = 0;
- q->handler = acpi_ec_get_query_handler(handler);
- ec_dbg_evt("Query(0x%02x) scheduled",
- q->handler->query_bit);
- /*
- * It is reported that _Qxx are evaluated in a
- * parallel way on Windows:
- * https://bugzilla.kernel.org/show_bug.cgi?id=94411
- */
- if (!schedule_work(&q->work))
- result = -EBUSY;
- break;
- }
+ 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 schedule_work() in order to make
+ * it appearing before any other log entries occurred during the
+ * work queue execution.
+ */
+ ec_dbg_evt("Query(0x%02x) scheduled", value);
+ if (!schedule_work(&q->work)) {
+ ec_dbg_evt("Query(0x%02x) overlapped", value);
+ result = -EBUSY;
}
- mutex_unlock(&ec->mutex);
err_exit:
- if (result && q)
+ if (result)
acpi_ec_delete_query(q);
if (data)
*data = value;
@@ -1354,19 +1393,13 @@ static int acpi_ec_add(struct acpi_device *device)
static int acpi_ec_remove(struct acpi_device *device)
{
struct acpi_ec *ec;
- struct acpi_ec_query_handler *handler, *tmp;
if (!device)
return -EINVAL;
ec = acpi_driver_data(device);
ec_remove_handlers(ec);
- mutex_lock(&ec->mutex);
- list_for_each_entry_safe(handler, tmp, &ec->list, node) {
- list_del(&handler->node);
- kfree(handler);
- }
- mutex_unlock(&ec->mutex);
+ acpi_ec_remove_query_handlers(ec, true, 0);
release_region(ec->data_addr, 1);
release_region(ec->command_addr, 1);
device->driver_data = NULL;
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-28 12:36:40 +0100