alistair23-linux/sound/firewire/digi00x/digi00x-transaction.c
Takashi Sakamoto 86c8dd7f4d ALSA: firewire-digi00x: delayed registration of sound card
When some digi00x units are connected sequentially, userspace
applications are involved at bus-reset state on IEEE 1394 bus. In the
state, any communications can be canceled. Therefore, sound card
registration should be delayed till the bus gets calm.

This commit achieves it.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2016-03-31 15:36:20 +02:00

143 lines
3.7 KiB
C

/*
* digi00x-transaction.c - a part of driver for Digidesign Digi 002/003 family
*
* Copyright (c) 2014-2015 Takashi Sakamoto
*
* Licensed under the terms of the GNU General Public License, version 2.
*/
#include <sound/asound.h>
#include "digi00x.h"
static int fill_midi_message(struct snd_rawmidi_substream *substream, u8 *buf)
{
int bytes;
buf[0] = 0x80;
bytes = snd_rawmidi_transmit_peek(substream, buf + 1, 2);
if (bytes >= 0)
buf[3] = 0xc0 | bytes;
return bytes;
}
static void handle_midi_control(struct snd_dg00x *dg00x, __be32 *buf,
unsigned int length)
{
struct snd_rawmidi_substream *substream;
unsigned int i;
unsigned int len;
u8 *b;
substream = ACCESS_ONCE(dg00x->in_control);
if (substream == NULL)
return;
length /= 4;
for (i = 0; i < length; i++) {
b = (u8 *)&buf[i];
len = b[3] & 0xf;
if (len > 0)
snd_rawmidi_receive(dg00x->in_control, b + 1, len);
}
}
static void handle_unknown_message(struct snd_dg00x *dg00x,
unsigned long long offset, __be32 *buf)
{
unsigned long flags;
spin_lock_irqsave(&dg00x->lock, flags);
dg00x->msg = be32_to_cpu(*buf);
spin_unlock_irqrestore(&dg00x->lock, flags);
wake_up(&dg00x->hwdep_wait);
}
static void handle_message(struct fw_card *card, struct fw_request *request,
int tcode, int destination, int source,
int generation, unsigned long long offset,
void *data, size_t length, void *callback_data)
{
struct snd_dg00x *dg00x = callback_data;
__be32 *buf = (__be32 *)data;
if (offset == dg00x->async_handler.offset)
handle_unknown_message(dg00x, offset, buf);
else if (offset == dg00x->async_handler.offset + 4)
handle_midi_control(dg00x, buf, length);
fw_send_response(card, request, RCODE_COMPLETE);
}
int snd_dg00x_transaction_reregister(struct snd_dg00x *dg00x)
{
struct fw_device *device = fw_parent_device(dg00x->unit);
__be32 data[2];
int err;
/* Unknown. 4bytes. */
data[0] = cpu_to_be32((device->card->node_id << 16) |
(dg00x->async_handler.offset >> 32));
data[1] = cpu_to_be32(dg00x->async_handler.offset);
err = snd_fw_transaction(dg00x->unit, TCODE_WRITE_BLOCK_REQUEST,
DG00X_ADDR_BASE + DG00X_OFFSET_MESSAGE_ADDR,
&data, sizeof(data), 0);
if (err < 0)
return err;
/* Asynchronous transactions for MIDI control message. */
data[0] = cpu_to_be32((device->card->node_id << 16) |
(dg00x->async_handler.offset >> 32));
data[1] = cpu_to_be32(dg00x->async_handler.offset + 4);
return snd_fw_transaction(dg00x->unit, TCODE_WRITE_BLOCK_REQUEST,
DG00X_ADDR_BASE + DG00X_OFFSET_MIDI_CTL_ADDR,
&data, sizeof(data), 0);
}
int snd_dg00x_transaction_register(struct snd_dg00x *dg00x)
{
static const struct fw_address_region resp_register_region = {
.start = 0xffffe0000000ull,
.end = 0xffffe000ffffull,
};
int err;
dg00x->async_handler.length = 12;
dg00x->async_handler.address_callback = handle_message;
dg00x->async_handler.callback_data = dg00x;
err = fw_core_add_address_handler(&dg00x->async_handler,
&resp_register_region);
if (err < 0)
return err;
err = snd_dg00x_transaction_reregister(dg00x);
if (err < 0)
goto error;
err = snd_fw_async_midi_port_init(&dg00x->out_control, dg00x->unit,
DG00X_ADDR_BASE + DG00X_OFFSET_MMC,
4, fill_midi_message);
if (err < 0)
goto error;
return err;
error:
fw_core_remove_address_handler(&dg00x->async_handler);
dg00x->async_handler.callback_data = NULL;
return err;
}
void snd_dg00x_transaction_unregister(struct snd_dg00x *dg00x)
{
if (dg00x->async_handler.callback_data == NULL)
return;
snd_fw_async_midi_port_destroy(&dg00x->out_control);
fw_core_remove_address_handler(&dg00x->async_handler);
dg00x->async_handler.callback_data = NULL;
}