ACPI: EC: wait for last write gpe
There is a possibility that EC might break if next command is
issued within 1 us after write or burst-disable command.
Suggestd-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index b340e08..cebd65d 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -102,6 +102,7 @@
u8 command;
u8 wlen;
u8 rlen;
+ bool done;
};
static struct acpi_ec {
@@ -178,7 +179,7 @@
unsigned long flags;
int ret = 0;
spin_lock_irqsave(&ec->curr_lock, flags);
- if (!ec->curr || (!ec->curr->wlen && !ec->curr->rlen))
+ if (!ec->curr || ec->curr->done)
ret = 1;
spin_unlock_irqrestore(&ec->curr_lock, flags);
return ret;
@@ -195,17 +196,20 @@
acpi_ec_write_data(ec, *(ec->curr->wdata++));
--ec->curr->wlen;
} else
- /* false interrupt, state didn't change */
- ++ec->curr->irq_count;
-
+ goto err;
} else if (ec->curr->rlen > 0) {
if ((status & ACPI_EC_FLAG_OBF) == 1) {
*(ec->curr->rdata++) = acpi_ec_read_data(ec);
- --ec->curr->rlen;
+ if (--ec->curr->rlen == 0)
+ ec->curr->done = true;
} else
- /* false interrupt, state didn't change */
- ++ec->curr->irq_count;
- }
+ goto err;
+ } else if (ec->curr->wlen == 0 && (status & ACPI_EC_FLAG_IBF) == 0)
+ ec->curr->done = true;
+ goto unlock;
+err:
+ /* false interrupt, state didn't change */
+ ++ec->curr->irq_count;
unlock:
spin_unlock_irqrestore(&ec->curr_lock, flags);
}
@@ -265,6 +269,7 @@
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);
if (ec->curr->command == ACPI_EC_COMMAND_QUERY)