diff options
| -rw-r--r-- | sound/firewire/cmp.c | 18 | ||||
| -rw-r--r-- | sound/firewire/cmp.h | 1 |
2 files changed, 19 insertions, 0 deletions
diff --git a/sound/firewire/cmp.c b/sound/firewire/cmp.c index 9da40d9e79da..d31a403ac539 100644 --- a/sound/firewire/cmp.c +++ b/sound/firewire/cmp.c @@ -152,6 +152,24 @@ int cmp_connection_init(struct cmp_connection *c, EXPORT_SYMBOL(cmp_connection_init); /** + * cmp_connection_check_used - check connection is already esablished or not + * @c: the connection manager to be checked + */ +int cmp_connection_check_used(struct cmp_connection *c, bool *used) +{ + __be32 pcr; + int err; + + err = snd_fw_transaction( + c->resources.unit, TCODE_READ_QUADLET_REQUEST, + pcr_address(c), &pcr, 4, 0); + if (err >= 0) + *used = (pcr & cpu_to_be32(PCR_BCAST_CONN | PCR_P2P_CONN_MASK)); + return err; +} +EXPORT_SYMBOL(cmp_connection_check_used); + +/** * cmp_connection_destroy - free connection manager resources * @c: the connection manager */ diff --git a/sound/firewire/cmp.h b/sound/firewire/cmp.h index 9b58448d5791..ebcb48484fca 100644 --- a/sound/firewire/cmp.h +++ b/sound/firewire/cmp.h @@ -38,6 +38,7 @@ int cmp_connection_init(struct cmp_connection *connection, struct fw_unit *unit, enum cmp_direction direction, unsigned int pcr_index); +int cmp_connection_check_used(struct cmp_connection *connection, bool *used); void cmp_connection_destroy(struct cmp_connection *connection); int cmp_connection_establish(struct cmp_connection *connection, |