Пример #1
0
static int init_request(struct client *client,
			struct fw_cdev_send_request *request,
			int destination_id, int speed)
{
	struct outbound_transaction_event *e;
	int ret;

	if (request->tcode != TCODE_STREAM_DATA &&
	    (request->length > 4096 || request->length > 512 << speed))
		return -EIO;

	e = kmalloc(sizeof(*e) + request->length, GFP_KERNEL);
	if (e == NULL)
		return -ENOMEM;

	e->client = client;
	e->response.length = request->length;
	e->response.closure = request->closure;

	if (request->data &&
	    copy_from_user(e->response.data,
			   u64_to_uptr(request->data), request->length)) {
		ret = -EFAULT;
		goto failed;
	}

	e->r.resource.release = release_transaction;
	ret = add_client_resource(client, &e->r.resource, GFP_KERNEL);
	if (ret < 0)
		goto failed;

	/* Get a reference for the transaction callback */
	client_get(client);

	fw_send_request(client->device->card, &e->r.transaction,
			request->tcode, destination_id, request->generation,
			speed, request->offset, e->response.data,
			request->length, complete_transaction, e);
	return 0;

 failed:
	kfree(e);

	return ret;
}
Пример #2
0
Файл: lib.c Проект: 020gzh/linux
static void midi_port_work(struct work_struct *work)
{
	struct snd_fw_async_midi_port *port =
			container_of(work, struct snd_fw_async_midi_port, work);
	struct snd_rawmidi_substream *substream = ACCESS_ONCE(port->substream);
	int generation;
	int type;

	/* Under transacting or error state. */
	if (!port->idling || port->error)
		return;

	/* Nothing to do. */
	if (substream == NULL || snd_rawmidi_transmit_empty(substream))
		return;

	/* Do it in next chance. */
	if (ktime_after(port->next_ktime, ktime_get())) {
		schedule_work(&port->work);
		return;
	}

	/*
	 * Fill the buffer. The callee must use snd_rawmidi_transmit_peek().
	 * Later, snd_rawmidi_transmit_ack() is called.
	 */
	memset(port->buf, 0, port->len);
	port->consume_bytes = port->fill(substream, port->buf);
	if (port->consume_bytes <= 0) {
		/* Do it in next chance, immediately. */
		if (port->consume_bytes == 0) {
			port->next_ktime = ktime_set(0, 0);
			schedule_work(&port->work);
		} else {
			/* Fatal error. */
			port->error = true;
		}
		return;
	}

	/* Calculate type of transaction. */
	if (port->len == 4)
		type = TCODE_WRITE_QUADLET_REQUEST;
	else
		type = TCODE_WRITE_BLOCK_REQUEST;

	/* Set interval to next transaction. */
	port->next_ktime = ktime_add_ns(ktime_get(),
				port->consume_bytes * 8 * NSEC_PER_SEC / 31250);

	/* 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
	 * this smp_rmb(), load/store instructions to memory are completed.
	 * Thus, both of generation and node id are available with recent
	 * values. This is a light-serialization solution to handle bus reset
	 * events on IEEE 1394 bus.
	 */
	generation = port->parent->generation;
	smp_rmb();

	fw_send_request(port->parent->card, &port->transaction, type,
			port->parent->node_id, generation,
			port->parent->max_speed, port->addr,
			port->buf, port->len, async_midi_port_callback,
			port);
}