diff --git a/sound/firewire/fcp.c b/sound/firewire/fcp.c index 860c08073c59..6876bfa9f27d 100644 --- a/sound/firewire/fcp.c +++ b/sound/firewire/fcp.c @@ -30,6 +30,7 @@ enum fcp_state { STATE_PENDING, STATE_BUS_RESET, STATE_COMPLETE, + STATE_DEFERRED, }; struct fcp_transaction { @@ -40,6 +41,7 @@ struct fcp_transaction { unsigned int response_match_bytes; enum fcp_state state; wait_queue_head_t wait; + bool deferrable; }; /** @@ -81,6 +83,9 @@ int fcp_avc_transaction(struct fw_unit *unit, t.state = STATE_PENDING; init_waitqueue_head(&t.wait); + if (*(const u8 *)command == 0x00 || *(const u8 *)command == 0x03) + t.deferrable = true; + spin_lock_irq(&transactions_lock); list_add_tail(&t.list, &transactions); spin_unlock_irq(&transactions_lock); @@ -93,11 +98,21 @@ int fcp_avc_transaction(struct fw_unit *unit, (void *)command, command_size, 0); if (ret < 0) break; - +deferred: wait_event_timeout(t.wait, t.state != STATE_PENDING, msecs_to_jiffies(FCP_TIMEOUT_MS)); - if (t.state == STATE_COMPLETE) { + if (t.state == STATE_DEFERRED) { + /* + * 'AV/C General Specification' define no time limit + * on command completion once an INTERIM response has + * been sent. but we promise to finish this function + * for a caller. Here we use FCP_TIMEOUT_MS for next + * interval. This is not in the specification. + */ + t.state = STATE_PENDING; + goto deferred; + } else if (t.state == STATE_COMPLETE) { ret = t.response_size; break; } else if (t.state == STATE_BUS_RESET) { @@ -132,7 +147,8 @@ void fcp_bus_reset(struct fw_unit *unit) spin_lock_irq(&transactions_lock); list_for_each_entry(t, &transactions, list) { if (t->unit == unit && - t->state == STATE_PENDING) { + (t->state == STATE_PENDING || + t->state == STATE_DEFERRED)) { t->state = STATE_BUS_RESET; wake_up(&t->wait); } @@ -186,10 +202,15 @@ static void fcp_response(struct fw_card *card, struct fw_request *request, if (t->state == STATE_PENDING && is_matching_response(t, data, length)) { - t->state = STATE_COMPLETE; - t->response_size = min((unsigned int)length, - t->response_size); - memcpy(t->response_buffer, data, t->response_size); + if (t->deferrable && *(const u8 *)data == 0x0f) { + t->state = STATE_DEFERRED; + } else { + t->state = STATE_COMPLETE; + t->response_size = min_t(unsigned int, length, + t->response_size); + memcpy(t->response_buffer, data, + t->response_size); + } wake_up(&t->wait); } }