Quelle  digi00x-transaction.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-only
/*
 * digi00x-transaction.c - a part of driver for Digidesign Digi 002/003 family
 *
 * Copyright (c) 2014-2015 Takashi Sakamoto
 */

#include <sound/asound.h>
#include "digi00x.h"

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;

 fw_send_response(card, request, RCODE_COMPLETE);

 if (offset == dg00x->async_handler.offset)
  handle_unknown_message(dg00x, offset, buf);
}

int snd_dg00x_transaction_reregister(struct snd_dg00x *dg00x)
{
 struct fw_device *device = fw_parent_device(dg00x->unit);
 __be32 data[2];

 /* 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);
 return snd_fw_transaction(dg00x->unit, TCODE_WRITE_BLOCK_REQUEST,
      DG00X_ADDR_BASE + DG00X_OFFSET_MESSAGE_ADDR,
      &data, sizeof(data), 0);
}

void snd_dg00x_transaction_unregister(struct snd_dg00x *dg00x)
{
 if (dg00x->async_handler.callback_data == NULL)
  return;

 fw_core_remove_address_handler(&dg00x->async_handler);

 dg00x->async_handler.callback_data = NULL;
}

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 = 4;
 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)
  snd_dg00x_transaction_unregister(dg00x);

 return err;
}