sound/soc/ath79/ath79-pcm.h

/*
 * ath-pcm.h -- ALSA PCM interface for the QCA Wasp based audio interface
 *
 * Copyright (c) 2013 The Linux Foundation. All rights reserved.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef _ATH_PCM_H_
#define _ATH_PCM_H_

#include <linux/sound.h>
#include <linux/list.h>
#include <linux/spinlock.h>

extern spinlock_t ath79_pcm_lock;

struct ath79_pcm_desc {
	unsigned int	OWN	:  1,    /* bit 31 */
			EOM	:  1,    /* bit 30 */
			rsvd1	:  6,    /* bit 29-24 */
			size	: 12,    /* bit 23-12 */
			length	: 12,    /* bit 11-00 */
			rsvd2	:  4,    /* bit 31-28 */
			BufPtr	: 28,    /* bit 27-00 */
			rsvd3	:  4,    /* bit 31-28 */
			NextPtr	: 28;    /* bit 27-00 */

	unsigned int Va[6];
	unsigned int Ua[6];
	unsigned int Ca[6];
	unsigned int Vb[6];
	unsigned int Ub[6];
	unsigned int Cb[6];

	/* Software specific data
	 * These data are not taken into account by the HW */
	struct list_head list; /* List linking all the buffer in virt@ space */
	dma_addr_t phys; /* Physical address of the descriptor */
};

struct ath79_pcm_rt_priv {
	struct list_head dma_head;
	struct ath79_pcm_desc *last_played;
	unsigned int elapsed_size;
	unsigned int delay_time;
	int direction;
};

/* Replaces struct ath_i2s_softc */
struct ath79_pcm_pltfm_priv {
	struct snd_pcm_substream *playback;
	struct snd_pcm_substream *capture;
};

/* platform data */
extern struct snd_soc_platform_driver ath79_soc_platform;

void ath79_mbox_interrupt_ack(u32);
void ath79_mbox_dma_start(struct ath79_pcm_rt_priv *);
void ath79_mbox_dma_stop(struct ath79_pcm_rt_priv *);
void ath79_mbox_dma_prepare(struct ath79_pcm_rt_priv *);
int ath79_mbox_dma_map(struct ath79_pcm_rt_priv *, dma_addr_t, int,int);
void ath79_mbox_dma_unmap(struct ath79_pcm_rt_priv *);
int ath79_mbox_dma_init(struct device *);
void ath79_mbox_dma_exit(void);
void ath79_mbox_dma_reset(void);

static inline unsigned int ath79_pcm_set_own_bits(struct ath79_pcm_rt_priv *rtpriv)
{
	struct ath79_pcm_desc *desc;
	unsigned int size_played = 0;

	spin_lock(&ath79_pcm_lock);
	list_for_each_entry(desc, &rtpriv->dma_head, list) {
		if (desc->OWN == 0) {
			desc->OWN = 1;
			size_played += desc->size;
		}
	}
	spin_unlock(&ath79_pcm_lock);
	return size_played;
}

static inline void ath79_pcm_clear_own_bits(struct ath79_pcm_rt_priv *rtpriv)
{
	struct ath79_pcm_desc *desc;

	spin_lock(&ath79_pcm_lock);
	list_for_each_entry(desc, &rtpriv->dma_head, list) {
		if (desc->OWN == 1) {
			desc->OWN = 0;
		}
	}
	spin_unlock(&ath79_pcm_lock);
}

static inline struct ath79_pcm_desc *ath79_pcm_get_last_played(struct ath79_pcm_rt_priv *rtpriv)
{
	struct ath79_pcm_desc *desc, *prev;

	spin_lock(&ath79_pcm_lock);
	prev = list_entry(rtpriv->dma_head.prev, struct ath79_pcm_desc, list);
	list_for_each_entry(desc, &rtpriv->dma_head, list) {
		if (desc->OWN == 1 && prev->OWN == 0) {
			return desc;
		}
		prev = desc;
	}
	spin_unlock(&ath79_pcm_lock);

	/* If we didn't find the last played buffer, return NULL */
	return NULL;
}

#endif /* _ATH_PCM_H_ */