diff options
Diffstat (limited to 'drivers/media/dvb-core/dvb_ringbuffer.h')
| -rw-r--r-- | drivers/media/dvb-core/dvb_ringbuffer.h | 280 |
1 files changed, 0 insertions, 280 deletions
diff --git a/drivers/media/dvb-core/dvb_ringbuffer.h b/drivers/media/dvb-core/dvb_ringbuffer.h deleted file mode 100644 index 8ed6bcc3a56e..000000000000 --- a/drivers/media/dvb-core/dvb_ringbuffer.h +++ /dev/null @@ -1,280 +0,0 @@ -/* - * - * dvb_ringbuffer.h: ring buffer implementation for the dvb driver - * - * Copyright (C) 2003 Oliver Endriss - * Copyright (C) 2004 Andrew de Quincey - * - * based on code originally found in av7110.c & dvb_ci.c: - * Copyright (C) 1999-2003 Ralph Metzler & Marcus Metzler - * for convergence integrated media GmbH - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU Lesser General Public License - * as published by the Free Software Foundation; either version 2.1 - * 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 Lesser General Public License for more details. - */ - -#ifndef _DVB_RINGBUFFER_H_ -#define _DVB_RINGBUFFER_H_ - -#include <linux/spinlock.h> -#include <linux/wait.h> - -/** - * struct dvb_ringbuffer - Describes a ring buffer used at DVB framework - * - * @data: Area were the ringbuffer data is written - * @size: size of the ringbuffer - * @pread: next position to read - * @pwrite: next position to write - * @error: used by ringbuffer clients to indicate that an error happened. - * @queue: Wait queue used by ringbuffer clients to indicate when buffer - * was filled - * @lock: Spinlock used to protect the ringbuffer - */ -struct dvb_ringbuffer { - u8 *data; - ssize_t size; - ssize_t pread; - ssize_t pwrite; - int error; - - wait_queue_head_t queue; - spinlock_t lock; -}; - -#define DVB_RINGBUFFER_PKTHDRSIZE 3 - -/** - * dvb_ringbuffer_init - initialize ring buffer, lock and queue - * - * @rbuf: pointer to struct dvb_ringbuffer - * @data: pointer to the buffer where the data will be stored - * @len: bytes from ring buffer into @buf - */ -extern void dvb_ringbuffer_init(struct dvb_ringbuffer *rbuf, void *data, - size_t len); - -/** - * dvb_ringbuffer_empty - test whether buffer is empty - * - * @rbuf: pointer to struct dvb_ringbuffer - */ -extern int dvb_ringbuffer_empty(struct dvb_ringbuffer *rbuf); - -/** - * dvb_ringbuffer_free - returns the number of free bytes in the buffer - * - * @rbuf: pointer to struct dvb_ringbuffer - * - * Return: number of free bytes in the buffer - */ -extern ssize_t dvb_ringbuffer_free(struct dvb_ringbuffer *rbuf); - -/** - * dvb_ringbuffer_avail - returns the number of bytes waiting in the buffer - * - * @rbuf: pointer to struct dvb_ringbuffer - * - * Return: number of bytes waiting in the buffer - */ -extern ssize_t dvb_ringbuffer_avail(struct dvb_ringbuffer *rbuf); - -/** - * dvb_ringbuffer_reset - resets the ringbuffer to initial state - * - * @rbuf: pointer to struct dvb_ringbuffer - * - * Resets the read and write pointers to zero and flush the buffer. - * - * This counts as a read and write operation - */ -extern void dvb_ringbuffer_reset(struct dvb_ringbuffer *rbuf); - -/* - * read routines & macros - */ - -/** - * dvb_ringbuffer_flush - flush buffer - * - * @rbuf: pointer to struct dvb_ringbuffer - */ -extern void dvb_ringbuffer_flush(struct dvb_ringbuffer *rbuf); - -/** - * dvb_ringbuffer_flush_spinlock_wakeup- flush buffer protected by spinlock - * and wake-up waiting task(s) - * - * @rbuf: pointer to struct dvb_ringbuffer - */ -extern void dvb_ringbuffer_flush_spinlock_wakeup(struct dvb_ringbuffer *rbuf); - -/** - * DVB_RINGBUFFER_PEEK - peek at byte @offs in the buffer - * - * @rbuf: pointer to struct dvb_ringbuffer - * @offs: offset inside the ringbuffer - */ -#define DVB_RINGBUFFER_PEEK(rbuf, offs) \ - ((rbuf)->data[((rbuf)->pread + (offs)) % (rbuf)->size]) - -/** - * DVB_RINGBUFFER_SKIP - advance read ptr by @num bytes - * - * @rbuf: pointer to struct dvb_ringbuffer - * @num: number of bytes to advance - */ -#define DVB_RINGBUFFER_SKIP(rbuf, num) {\ - (rbuf)->pread = ((rbuf)->pread + (num)) % (rbuf)->size;\ -} - -/** - * dvb_ringbuffer_read_user - Reads a buffer into a user pointer - * - * @rbuf: pointer to struct dvb_ringbuffer - * @buf: pointer to the buffer where the data will be stored - * @len: bytes from ring buffer into @buf - * - * This variant assumes that the buffer is a memory at the userspace. So, - * it will internally call copy_to_user(). - * - * Return: number of bytes transferred or -EFAULT - */ -extern ssize_t dvb_ringbuffer_read_user(struct dvb_ringbuffer *rbuf, - u8 __user *buf, size_t len); - -/** - * dvb_ringbuffer_read - Reads a buffer into a pointer - * - * @rbuf: pointer to struct dvb_ringbuffer - * @buf: pointer to the buffer where the data will be stored - * @len: bytes from ring buffer into @buf - * - * This variant assumes that the buffer is a memory at the Kernel space - * - * Return: number of bytes transferred or -EFAULT - */ -extern void dvb_ringbuffer_read(struct dvb_ringbuffer *rbuf, - u8 *buf, size_t len); - -/* - * write routines & macros - */ - -/** - * DVB_RINGBUFFER_WRITE_BYTE - write single byte to ring buffer - * - * @rbuf: pointer to struct dvb_ringbuffer - * @byte: byte to write - */ -#define DVB_RINGBUFFER_WRITE_BYTE(rbuf, byte) \ - { (rbuf)->data[(rbuf)->pwrite] = (byte); \ - (rbuf)->pwrite = ((rbuf)->pwrite + 1) % (rbuf)->size; } - -/** - * dvb_ringbuffer_write - Writes a buffer into the ringbuffer - * - * @rbuf: pointer to struct dvb_ringbuffer - * @buf: pointer to the buffer where the data will be read - * @len: bytes from ring buffer into @buf - * - * This variant assumes that the buffer is a memory at the Kernel space - * - * return: number of bytes transferred or -EFAULT - */ -extern ssize_t dvb_ringbuffer_write(struct dvb_ringbuffer *rbuf, const u8 *buf, - size_t len); - -/** - * dvb_ringbuffer_write_user - Writes a buffer received via a user pointer - * - * @rbuf: pointer to struct dvb_ringbuffer - * @buf: pointer to the buffer where the data will be read - * @len: bytes from ring buffer into @buf - * - * This variant assumes that the buffer is a memory at the userspace. So, - * it will internally call copy_from_user(). - * - * Return: number of bytes transferred or -EFAULT - */ -extern ssize_t dvb_ringbuffer_write_user(struct dvb_ringbuffer *rbuf, - const u8 __user *buf, size_t len); - -/** - * dvb_ringbuffer_pkt_write - Write a packet into the ringbuffer. - * - * @rbuf: Ringbuffer to write to. - * @buf: Buffer to write. - * @len: Length of buffer (currently limited to 65535 bytes max). - * - * Return: Number of bytes written, or -EFAULT, -ENOMEM, -EVINAL. - */ -extern ssize_t dvb_ringbuffer_pkt_write(struct dvb_ringbuffer *rbuf, u8 *buf, - size_t len); - -/** - * dvb_ringbuffer_pkt_read_user - Read from a packet in the ringbuffer. - * - * @rbuf: Ringbuffer concerned. - * @idx: Packet index as returned by dvb_ringbuffer_pkt_next(). - * @offset: Offset into packet to read from. - * @buf: Destination buffer for data. - * @len: Size of destination buffer. - * - * Return: Number of bytes read, or -EFAULT. - * - * .. note:: - * - * unlike dvb_ringbuffer_read(), this does **NOT** update the read pointer - * in the ringbuffer. You must use dvb_ringbuffer_pkt_dispose() to mark a - * packet as no longer required. - */ -extern ssize_t dvb_ringbuffer_pkt_read_user(struct dvb_ringbuffer *rbuf, - size_t idx, - int offset, u8 __user *buf, - size_t len); - -/** - * dvb_ringbuffer_pkt_read - Read from a packet in the ringbuffer. - * Note: unlike dvb_ringbuffer_read_user(), this DOES update the read pointer - * in the ringbuffer. - * - * @rbuf: Ringbuffer concerned. - * @idx: Packet index as returned by dvb_ringbuffer_pkt_next(). - * @offset: Offset into packet to read from. - * @buf: Destination buffer for data. - * @len: Size of destination buffer. - * - * Return: Number of bytes read, or -EFAULT. - */ -extern ssize_t dvb_ringbuffer_pkt_read(struct dvb_ringbuffer *rbuf, size_t idx, - int offset, u8 *buf, size_t len); - -/** - * dvb_ringbuffer_pkt_dispose - Dispose of a packet in the ring buffer. - * - * @rbuf: Ring buffer concerned. - * @idx: Packet index as returned by dvb_ringbuffer_pkt_next(). - */ -extern void dvb_ringbuffer_pkt_dispose(struct dvb_ringbuffer *rbuf, size_t idx); - -/** - * dvb_ringbuffer_pkt_next - Get the index of the next packet in a ringbuffer. - * - * @rbuf: Ringbuffer concerned. - * @idx: Previous packet index, or -1 to return the first packet index. - * @pktlen: On success, will be updated to contain the length of the packet - * in bytes. - * returns Packet index (if >=0), or -1 if no packets available. - */ -extern ssize_t dvb_ringbuffer_pkt_next(struct dvb_ringbuffer *rbuf, - size_t idx, size_t *pktlen); - -#endif /* _DVB_RINGBUFFER_H_ */ |