path: root/sound/ppc/pmac.c

/*
 * PMac DBDMA lowlevel functions
 *
 * Copyright (c) by Takashi Iwai <tiwai@suse.de>
 * code based on dmasound.c.
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */


#include <asm/io.h>
#include <asm/irq.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <sound/core.h>
#include "pmac.h"
#include <sound/pcm_params.h>
#include <asm/pmac_feature.h>
#include <asm/pci-bridge.h>


/* fixed frequency table for awacs, screamer, burgundy, DACA (44100 max) */
static int awacs_freqs[8] = {
	44100, 29400, 22050, 17640, 14700, 11025, 8820, 7350
};
/* fixed frequency table for tumbler */
static int tumbler_freqs[1] = {
	44100
};


/*
 * we will allocate a single 'emergency' dbdma cmd block to use if the
 * tx status comes up "DEAD".  This happens on some PowerComputing Pmac
 * clones, either owing to a bug in dbdma or some interaction between
 * IDE and sound.  However, this measure would deal with DEAD status if
 * it appeared elsewhere.
 */
static struct pmac_dbdma emergency_dbdma;
static int emergency_in_use;


/*
 * allocate DBDMA command arrays
 */
static int snd_pmac_dbdma_alloc(struct snd_pmac *chip, struct pmac_dbdma *rec, int size)
{
	unsigned int rsize = sizeof(struct dbdma_cmd) * (size + 1);

	rec->space = dma_alloc_coherent(&chip->pdev->dev, rsize,
					&rec->dma_base, GFP_KERNEL);
	if (rec->space == NULL)
		return -ENOMEM;
	rec->size = size;
	memset(rec->space, 0, rsize);
	rec->cmds = (void __iomem *)DBDMA_ALIGN(rec->space);
	rec->addr = rec->dma_base + (unsigned long)((char *)rec->cmds - (char *)rec->space);

	return 0;
}

static void snd_pmac_dbdma_free(struct snd_pmac *chip, struct pmac_dbdma *rec)
{
	if (rec->space) {
		unsigned int rsize = sizeof(struct dbdma_cmd) * (rec->size + 1);

		dma_free_coherent(&chip->pdev->dev, rsize, rec->space, rec->dma_base);
	}
}


/*
 * pcm stuff
 */

/*
 * look up frequency table
 */

unsigned int snd_pmac_rate_index(struct snd_pmac *chip, struct pmac_stream *rec, unsigned int rate)
{
	int i, ok, found;

	ok = rec->cur_freqs;
	if (rate > chip->freq_table[0])
		return 0;
	found = 0;
	for (i = 0; i < chip->num_freqs; i++, ok >>= 1) {
		if (! (ok & 1)) continue;
		found = i;
		if (rate >= chip->freq_table[i])
			break;
	}
	return found;
}

/*
 * check whether another stream is active
 */
static inline int another_stream(int stream)
{
	return (stream == SNDRV_PCM_STREAM_PLAYBACK) ?
		SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK;
}

/*
 * allocate buffers
 */
static int snd_pmac_pcm_hw_params(struct snd_pcm_substream *subs,
				  struct snd_pcm_hw_params *hw_params)
{
	return snd_pcm_lib_malloc_pages(subs, params_buffer_bytes(hw_params));
}

/*
 * release buffers
 */
static int snd_pmac_pcm_hw_free(struct