diff --git a/sound/firewire/motu/motu-register-dsp-message-parser.c b/sound/firewire/motu/motu-register-dsp-message-parser.c index a8053e3ef065..4ec23e6880d9 100644 --- a/sound/firewire/motu/motu-register-dsp-message-parser.c +++ b/sound/firewire/motu/motu-register-dsp-message-parser.c @@ -386,6 +386,8 @@ unsigned int snd_motu_register_dsp_message_parser_count_event(struct snd_motu *m { struct msg_parser *parser = motu->message_parser; + guard(spinlock_irqsave)(&parser->lock); + if (parser->pull_pos > parser->push_pos) return EVENT_QUEUE_SIZE - parser->pull_pos + parser->push_pos; else @@ -395,13 +397,14 @@ unsigned int snd_motu_register_dsp_message_parser_count_event(struct snd_motu *m bool snd_motu_register_dsp_message_parser_copy_event(struct snd_motu *motu, u32 *event) { struct msg_parser *parser = motu->message_parser; - unsigned int pos = parser->pull_pos; - - if (pos == parser->push_pos) - return false; + unsigned int pos; guard(spinlock_irqsave)(&parser->lock); + if (parser->pull_pos == parser->push_pos) + return false; + + pos = parser->pull_pos; *event = parser->event_queue[pos]; ++pos;