During the period that a work queue is scheduled (queued up for run) but
hasn't been run, second schedule_work() could fail. This may not lead to
the loss of queries because QR_EC is always ensured to be submitted after
the work queue has been in the running state.
Thus except the logging message changes, this patch is just a no-op. But
the event handling work queue can be changed into the loop style to allow
us to control the code in a more flexible way (for example, adding
event=0x00 termination condition in the loop).
Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx>
Tested-by: Gabriele Mazzotta <gabriele.mzt@xxxxxxxxx>
Tested-by: Tigran Gabrielyan <tigrangab@xxxxxxxxx>
Tested-by: Adrien D <ghbdtn@xxxxxxxxxxxxxxx>
---
drivers/acpi/ec.c | 33 ++++++++++++++++++++++++---------
drivers/acpi/internal.h | 1 +
2 files changed, 25 insertions(+), 9 deletions(-)
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index b956dbc..7a30f59 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -384,7 +384,9 @@ 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);
}
}
@@ -393,7 +395,8 @@ static void acpi_ec_complete_query(struct acpi_ec *ec)
{
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));
}
}
@@ -460,8 +463,8 @@ static void advance_transaction(struct acpi_ec *ec)
if (t->rlen == t->ri) {
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
@@ -479,8 +482,8 @@ static void advance_transaction(struct acpi_ec *ec)
ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL);
t->rdata[t->ri++] = 0x00;
ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
- ec_dbg_req("Command(%s) software completion",
- acpi_ec_cmd_string(t->command));
+ 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);
@@ -950,11 +953,23 @@ 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_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--;
+ }
+ spin_unlock_irqrestore(&ec->lock, flags);
+
+ ec_dbg_evt("Event stopped");
}
static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
@@ -1029,7 +1044,7 @@ 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;
}
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index cf358d4..ae919b5 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -139,6 +139,7 @@ struct acpi_ec {
spinlock_t lock;
struct work_struct work;
unsigned long timestamp;
+ unsigned long nr_pending_queries;
};
extern struct acpi_ec *first_ec;
--
1.7.10
--
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