-/*
- * This file is part of OMAP DSP driver (DSP Gateway version 3.3.1)
- *
- * Copyright (C) 2002-2006 Nokia Corporation. All rights reserved.
- *
- * Contact: Toshihiro Kobayashi <toshihiro.kobayashi@nokia.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * version 2 as published by the Free Software Foundation.
- *
- * 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., 51 Franklin St, Fifth Floor, Boston, MA
- * 02110-1301 USA
- *
- */
-
-#ifndef __PLAT_OMAP_DSP_FIFO_H
-#define __PLAT_OMAP_DSP_FIFO_H
-
-struct fifo_struct {
- spinlock_t lock;
- char *buf;
- size_t sz;
- size_t cnt;
- unsigned int wp;
-};
-
-static inline int alloc_fifo(struct fifo_struct *fifo, size_t sz)
-{
- if ((fifo->buf = kmalloc(sz, GFP_KERNEL)) == NULL) {
- fifo->sz = 0;
- return -ENOMEM;
- }
- fifo->sz = sz;
- fifo->cnt = 0;
- fifo->wp = 0;
- return 0;
-}
-
-static inline int init_fifo(struct fifo_struct *fifo, size_t sz)
-{
- spin_lock_init(&fifo->lock);
- return alloc_fifo(fifo, sz);
-}
-
-static inline void free_fifo(struct fifo_struct *fifo)
-{
- spin_lock(&fifo->lock);
- if (fifo->buf == NULL) {
- spin_unlock(&fifo->lock);
- return;
- }
-
- kfree(fifo->buf);
- fifo->buf = NULL;
- fifo->sz = 0;
- spin_unlock(&fifo->lock);
-}
-
-static inline void flush_fifo(struct fifo_struct *fifo)
-{
- spin_lock(&fifo->lock);
- fifo->cnt = 0;
- fifo->wp = 0;
- spin_unlock(&fifo->lock);
-}
-
-#define fifo_empty(fifo) ((fifo)->cnt == 0)
-
-static inline int realloc_fifo(struct fifo_struct *fifo, size_t sz)
-{
- int ret = sz;
-
- spin_lock(&fifo->lock);
- if (!fifo_empty(fifo)) {
- ret = -EBUSY;
- goto out;
- }
-
- /* free */
- if (fifo->buf)
- kfree(fifo->buf);
-
- /* alloc */
- ret = alloc_fifo(fifo, sz);
-
-out:
- spin_unlock(&fifo->lock);
- return ret;
-}
-
-static inline void write_word_to_fifo(struct fifo_struct *fifo, u16 word)
-{
- spin_lock(&fifo->lock);
- *(u16 *)&fifo->buf[fifo->wp] = word;
- if ((fifo->wp += 2) == fifo->sz)
- fifo->wp = 0;
- if ((fifo->cnt += 2) > fifo->sz)
- fifo->cnt = fifo->sz;
- spin_unlock(&fifo->lock);
-}
-
-/*
- * (before)
- *
- * [*******----------*************]
- * ^wp
- * <----------------------------> sz = 30
- * <-----> <-----------> cnt = 20
- *
- * (read: count=16)
- * <-> <-----------> count = 16
- * <-----------> cnt1 = 13
- * ^rp
- *
- * (after)
- * [---****-----------------------]
- * ^wp
- */
-static inline ssize_t copy_to_user_fm_fifo(char *dst, struct fifo_struct *fifo,
- size_t count)
-{
- int rp;
- ssize_t ret;
-
- /* fifo size can be zero */
- if (fifo->sz == 0)
- return 0;
-
- spin_lock(&fifo->lock);
- if (count > fifo->cnt)
- count = fifo->cnt;
-
- if ((rp = fifo->wp - fifo->cnt) >= 0) {
- /* valid area is straight */
- if (copy_to_user(dst, &fifo->buf[rp], count)) {
- ret = -EFAULT;
- goto out;
- }
- } else {
- int cnt1 = -rp;
- rp += fifo->sz;
- if (cnt1 >= count) {
- /* requested area is straight */
- if (copy_to_user(dst, &fifo->buf[rp], count)) {
- ret = -EFAULT;
- goto out;
- }
- } else {
- if (copy_to_user(dst, &fifo->buf[rp], cnt1)) {
- ret = -EFAULT;
- goto out;
- }
- if (copy_to_user(dst+cnt1, fifo->buf, count-cnt1)) {
- ret = -EFAULT;
- goto out;
- }
- }
- }
- fifo->cnt -= count;
- ret = count;
-
-out:
- spin_unlock(&fifo->lock);
- return ret;
-}
-
-#endif /* __PLAT_OMAP_DSP_FIFO_H */