2.6.27-stable review patch. If anyone has any objections, please let us know.
------------------
From: Alexey Starikovskiy <astarikovskiy@suse.de>
commit a2f93aeadf97e870ff385030633a73e21146815d upstream.
Restart current transaction if we recieved unexpected GPEs instead
of needed ones.
http://bugzilla.kernel.org/show_bug.cgi?id=11896
Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
drivers/acpi/ec.c | 41 +++++++++++++++++++++++++++++------------
1 file changed, 29 insertions(+), 12 deletions(-)
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -100,6 +100,8 @@ struct transaction {
u8 *rdata;
unsigned short irq_count;
u8 command;
+ u8 wi;
+ u8 ri;
u8 wlen;
u8 rlen;
bool done;
@@ -185,26 +187,34 @@ static int ec_transaction_done(struct ac
return ret;
}
+static void start_transaction(struct acpi_ec *ec)
+{
+ ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
+ ec->curr->done = false;
+ acpi_ec_write_cmd(ec, ec->curr->command);
+}
+
static void gpe_transaction(struct acpi_ec *ec, u8 status)
{
unsigned long flags;
spin_lock_irqsave(&ec->curr_lock, flags);
if (!ec->curr)
goto unlock;
- if (ec->curr->wlen > 0) {
- if ((status & ACPI_EC_FLAG_IBF) == 0) {
- acpi_ec_write_data(ec, *(ec->curr->wdata++));
- --ec->curr->wlen;
- } else
+ if (ec->curr->wlen > ec->curr->wi) {
+ if ((status & ACPI_EC_FLAG_IBF) == 0)
+ acpi_ec_write_data(ec,
+ ec->curr->wdata[ec->curr->wi++]);
+ else
goto err;
- } else if (ec->curr->rlen > 0) {
+ } else if (ec->curr->rlen > ec->curr->ri) {
if ((status & ACPI_EC_FLAG_OBF) == 1) {
- *(ec->curr->rdata++) = acpi_ec_read_data(ec);
- if (--ec->curr->rlen == 0)
+ ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
+ if (ec->curr->rlen == ec->curr->ri)
ec->curr->done = true;
} else
goto err;
- } else if (ec->curr->wlen == 0 && (status & ACPI_EC_FLAG_IBF) == 0)
+ } else if (ec->curr->wlen == ec->curr->wi &&
+ (status & ACPI_EC_FLAG_IBF) == 0)
ec->curr->done = true;
goto unlock;
err:
@@ -219,6 +229,15 @@ static int acpi_ec_wait(struct acpi_ec *
if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
msecs_to_jiffies(ACPI_EC_DELAY)))
return 0;
+ /* try restart command if we get any false interrupts */
+ if (ec->curr->irq_count &&
+ (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
+ pr_debug(PREFIX "controller reset, restart transaction\n");
+ start_transaction(ec);
+ if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
+ msecs_to_jiffies(ACPI_EC_DELAY)))
+ return 0;
+ }
/* missing GPEs, switch back to poll mode */
if (printk_ratelimit())
pr_info(PREFIX "missing confirmations, "
@@ -268,10 +287,8 @@ static int acpi_ec_transaction_unlocked(
/* start transaction */
spin_lock_irqsave(&ec->curr_lock, tmp);
/* following two actions should be kept atomic */
- t->irq_count = 0;
- t->done = false;
ec->curr = t;
- acpi_ec_write_cmd(ec, ec->curr->command);
+ start_transaction(ec);
if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
spin_unlock_irqrestore(&ec->curr_lock, tmp);
--
--
