Merge branch 'for-joerg/arm-smmu/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into iommu/fixes

1 files changed, 18 insertions, 3 deletions

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index a66ab658abbc..9922cc46b15c 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -197,6 +197,8 @@ static bool advance_transaction(struct acpi_ec *ec)
 				t->rdata[t->ri++] = acpi_ec_read_data(ec);
 				if (t->rlen == t->ri) {
 					t->flags |= ACPI_EC_COMMAND_COMPLETE;
+					if (t->command == ACPI_EC_COMMAND_QUERY)
+						pr_debug("hardware QR_EC completion\n");
 					wakeup = true;
 				}
 			} else
@@ -208,7 +210,20 @@ static bool advance_transaction(struct acpi_ec *ec)
 		}
 		return wakeup;
 	} else {
-		if ((status & ACPI_EC_FLAG_IBF) == 0) {
+		/*
+		 * There is firmware refusing to respond QR_EC when SCI_EVT
+		 * is not set, for which case, we complete the QR_EC
+		 * without issuing it to the firmware.
+		 * https://bugzilla.kernel.org/show_bug.cgi?id=86211
+		 */
+		if (!(status & ACPI_EC_FLAG_SCI) &&
+		    (t->command == ACPI_EC_COMMAND_QUERY)) {
+			t->flags |= ACPI_EC_COMMAND_POLL;
+			t->rdata[t->ri++] = 0x00;
+			t->flags |= ACPI_EC_COMMAND_COMPLETE;
+			pr_debug("software QR_EC completion\n");
+			wakeup = true;
+		} else if ((status & ACPI_EC_FLAG_IBF) == 0) {
 			acpi_ec_write_cmd(ec, t->command);
 			t->flags |= ACPI_EC_COMMAND_POLL;
 		} else
@@ -288,11 +303,11 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 	/* following two actions should be kept atomic */
 	ec->curr = t;
 	start_transaction(ec);
-	if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
-		clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 	spin_unlock_irqrestore(&ec->lock, tmp);
 	ret = ec_poll(ec);
 	spin_lock_irqsave(&ec->lock, tmp);
+	if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
+		clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 	ec->curr = NULL;
 	spin_unlock_irqrestore(&ec->lock, tmp);
 	return ret;