leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

ALSA: firewire-lib: add a restriction for a transaction at once

Browse Source 
Currently, when waiting for a response, callers can start another
transaction by scheduling another work. This is not good for error
processing of transaction, especially the first response is too late.

This commit serialize request/response transactions, by adding one
boolean member to represent idling state.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Sakamoto 2015-10-09 08:10:26 +09:00 committed by Takashi Iwai
parent 585d7cba5e
commit d3ef9cb93a
2 changed files with 10 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
sound/firewire/lib.c
View File

@ -76,6 +76,8 @@ static void async_midi_port_callback(struct fw_card *card, int rcode,
if (rcode == RCODE_COMPLETE && substream != NULL)
snd_rawmidi_transmit_ack(substream, port->consume_bytes);
port->idling = true;
}
static void midi_port_work(struct work_struct *work)
@ -86,6 +88,10 @@ static void midi_port_work(struct work_struct *work)
int generation;
int type;
/* Under transacting. */
if (!port->idling)
return;
/* Nothing to do. */
if (substream == NULL || snd_rawmidi_transmit_empty(substream))
return;
@ -110,6 +116,8 @@ static void midi_port_work(struct work_struct *work)
type = TCODE_WRITE_BLOCK_REQUEST;
/* Start this transaction. */
port->idling = false;
/*
* In Linux FireWire core, when generation is updated with memory
* barrier, node id has already been updated. In this module, After
@ -150,6 +158,7 @@ int snd_fw_async_midi_port_init(struct snd_fw_async_midi_port *port,
port->parent = fw_parent_device(unit);
port->addr = addr;
port->fill = fill;
port->idling = true;
INIT_WORK(&port->work, midi_port_work);

1
sound/firewire/lib.h
View File

@ -30,6 +30,7 @@ typedef int (*snd_fw_async_midi_port_fill)(
struct snd_fw_async_midi_port {
struct fw_device *parent;
struct work_struct work;
bool idling;
u64 addr;
struct fw_transaction transaction;