ALSA: firewire: extend snd_fw_transaction()

Add a flag to snd_fw_transaction() to allow it to abort when a bus reset
happens.  This removes most of the duplicated error handling loops that
were required around calls to the low-level fw_run_transaction().

Also add a flag to suppress error messages; errors are expected when we
attempt to clean up after the device was unplugged.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

1 files changed, 6 insertions, 2 deletions

diff --git a/sound/firewire/scs1x.c b/sound/firewire/scs1x.c
index 505fc8123199..858023cf4298 100644
--- a/sound/firewire/scs1x.c
+++ b/sound/firewire/scs1x.c
@@ -369,7 +369,7 @@ static int scs_init_hss_address(struct scs *scs)
         data = cpu_to_be64(((u64)HSS1394_TAG_CHANGE_ADDRESS << 56) |
                            scs->hss_handler.offset);
         err = snd_fw_transaction(scs->unit, TCODE_WRITE_BLOCK_REQUEST,
-                                 HSS1394_ADDRESS, &data, 8);
+                                 HSS1394_ADDRESS, &data, 8, 0);
         if (err < 0)
                 dev_err(&scs->unit->device, "HSS1394 communication failed\n");
 
@@ -455,12 +455,16 @@ err_card:
 static void scs_update(struct fw_unit *unit)
 {
         struct scs *scs = dev_get_drvdata(&unit->device);
+        int generation;
         __be64 data;
 
         data = cpu_to_be64(((u64)HSS1394_TAG_CHANGE_ADDRESS << 56) |
                            scs->hss_handler.offset);
+        generation = fw_parent_device(unit)->generation;
+        smp_rmb(); /* node_id vs. generation */
         snd_fw_transaction(scs->unit, TCODE_WRITE_BLOCK_REQUEST,
-                           HSS1394_ADDRESS, &data, 8);
+                           HSS1394_ADDRESS, &data, 8,
+                           FW_FIXED_GENERATION | generation);
 }
 
 static void scs_remove(struct fw_unit *unit)