/* * SPDX-License-Identifier: GPL-2.0 * * dvb-vb2.h - DVB driver helper framework for streaming I/O * * Copyright (C) 2015 Samsung Electronics * * Author: jh1009.sung@samsung.com * * 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. */ #ifndef _DVB_VB2_H #define _DVB_VB2_H #include <linux/mutex.h> #include <linux/poll.h> #include <linux/dvb/dmx.h> #include <media/videobuf2-core.h> #include <media/videobuf2-dma-contig.h> #include <media/videobuf2-vmalloc.h> /** * enum dvb_buf_type - types of Digital TV memory-mapped buffers * * @DVB_BUF_TYPE_CAPTURE: buffer is filled by the Kernel, * with a received Digital TV stream */ enum dvb_buf_type { DVB_BUF_TYPE_CAPTURE = 1, }; /** * enum dvb_vb2_states - states to control VB2 state machine * @DVB_VB2_STATE_NONE: * VB2 engine not initialized yet, init failed or VB2 was released. * @DVB_VB2_STATE_INIT: * VB2 engine initialized. * @DVB_VB2_STATE_REQBUFS: * Buffers were requested * @DVB_VB2_STATE_STREAMON: * VB2 is streaming. Callers should not check it directly. Instead, * they should use dvb_vb2_is_streaming(). * * Note: * * Callers should not touch at the state machine directly. This * is handled inside dvb_vb2.c. */ enum dvb_vb2_states { DVB_VB2_STATE_NONE = 0x0, DVB_VB2_STATE_INIT = 0x1, DVB_VB2_STATE_REQBUFS = 0x2, DVB_VB2_STATE_STREAMON = 0x4, }; #define DVB_VB2_NAME_MAX (20) /** * struct dvb_buffer - video buffer information for v4l2. * * @vb: embedded struct &vb2_buffer. * @list: list of &struct dvb_buffer. */ struct dvb_buffer { struct vb2_buffer vb; struct list_head list; }; /** * struct dvb_vb2_ctx - control struct for VB2 handler * @vb_q: pointer to &struct vb2_queue with videobuf2 queue. * @slock: spin lock used to protect buffer filling at dvb_vb2.c. * @dvb_q: List of buffers that are not filled yet. * @buf: Pointer to the buffer that are currently being filled. * @offset: index to the next position at the @buf to be filled. * @remain: How many bytes are left to be filled at @buf. * @state: bitmask of buffer states as defined by &enum dvb_vb2_states. * @buf_siz: size of each VB2 buffer. * @buf_cnt: number of VB2 buffers. * @nonblocking: * If different than zero, device is operating on non-blocking * mode. * @flags: buffer flags as defined by &enum dmx_buffer_flags. * Filled only at &DMX_DQBUF. &DMX_QBUF should zero this field. * @count: monotonic counter for filled buffers. Helps to identify * data stream loses. Filled only at &DMX_DQBUF. &DMX_QBUF should * zero this field. * * @name: name of the device type. Currently, it can either be * "dvr" or "demux_filter". */ struct dvb_vb2_ctx { struct vb2_queue vb_q; spinlock_t slock; struct list_head dvb_q; struct dvb_buffer *buf; int offset; int remain; int state; int buf_siz; int buf_cnt; int nonblocking; enum dmx_buffer_flags flags; u32 count; char name[DVB_VB2_NAME_MAX + 1]; }; #ifndef CONFIG_DVB_MMAP static inline int dvb_vb2_init(struct dvb_vb2_ctx *ctx, const char *name, struct mutex *mutex, int non_blocking) { return 0; }; static inline int dvb_vb2_release(struct dvb_vb2_ctx *ctx) { return 0; }; #define dvb_vb2_is_streaming(ctx) (0) #define dvb_vb2_fill_buffer(ctx, file, wait, flags, flush) (0) static inline __poll_t dvb_vb2_poll(struct dvb_vb2_ctx *ctx, struct file *file, poll_table *wait) { return 0; } #else /** * dvb_vb2_init - initializes VB2 handler * * @ctx: control struct for VB2 handler * @name: name for the VB2 handler * @mutex: pointer to the mutex that serializes vb2 ioctls * @non_blocking: * if not zero, it means that the device is at non-blocking mode */ int dvb_vb2_init(struct dvb_vb2_ctx *ctx, const char *name, struct mutex *mutex, int non_blocking); /** * dvb_vb2_release - Releases the VB2 handler allocated resources and * put @ctx at DVB_VB2_STATE_NONE state. * @ctx: control struct for VB2 handler */ int dvb_vb2_release(struct dvb_vb2_ctx *ctx); /** * dvb_vb2_is_streaming - checks if the VB2 handler is streaming * @ctx: control struct for VB2 handler * * Return: 0 if not streaming, 1 otherwise. */ int dvb_vb2_is_streaming(struct dvb_vb2_ctx *ctx); /** * dvb_vb2_fill_buffer - fills a VB2 buffer * @ctx: control struct for VB2 handler * @src: place where the data is stored * @len: number of bytes to be copied from @src * @buffer_flags: * pointer to buffer flags as defined by &enum dmx_buffer_flags. * can be NULL. * @flush: flush the buffer, even if it isn't full. */ int dvb_vb2_fill_buffer(struct dvb_vb2_ctx *ctx, const unsigned char *src, int len, enum dmx_buffer_flags *buffer_flags, bool flush); /** * dvb_vb2_poll - Wrapper to vb2_core_streamon() for Digital TV * buffer handling. * * @ctx: control struct for VB2 handler * @file: &struct file argument passed to the poll * file operation handler. * @wait: &poll_table wait argument passed to the poll * file operation handler. * * Implements poll syscall() logic. */ __poll_t dvb_vb2_poll(struct dvb_vb2_ctx *ctx, struct file *file, poll_table *wait); #endif /** * dvb_vb2_stream_on() - Wrapper to vb2_core_streamon() for Digital TV * buffer handling. * * @ctx: control struct for VB2 handler * * Starts dvb streaming */ int dvb_vb2_stream_on(struct dvb_vb2_ctx *ctx); /** * dvb_vb2_stream_off() - Wrapper to vb2_core_streamoff() for Digital TV * buffer handling. * * @ctx: control struct for VB2 handler * * Stops dvb streaming */ int dvb_vb2_stream_off(struct dvb_vb2_ctx *ctx); /** * dvb_vb2_reqbufs() - Wrapper to vb2_core_reqbufs() for Digital TV * buffer handling. * * @ctx: control struct for VB2 handler * @req: &struct dmx_requestbuffers passed from userspace in * order to handle &DMX_REQBUFS. * * Initiate streaming by requesting a number of buffers. Also used to * free previously requested buffers, is ``req->count`` is zero. */ int dvb_vb2_reqbufs(struct dvb_vb2_ctx *ctx, struct dmx_requestbuffers *req); /** * dvb_vb2_querybuf() - Wrapper to vb2_core_querybuf() for Digital TV * buffer handling. * * @ctx: control struct for VB2 handler * @b: &struct dmx_buffer passed from userspace in * order to handle &DMX_QUERYBUF. * * */ int dvb_vb2_querybuf(struct dvb_vb2_ctx *ctx, struct dmx_buffer *b); /** * dvb_vb2_expbuf() - Wrapper to vb2_core_expbuf() for Digital TV * buffer handling. * * @ctx: control struct for VB2 handler * @exp: &struct dmx_exportbuffer passed from userspace in * order to handle &DMX_EXPBUF. * * Export a buffer as a file descriptor. */ int dvb_vb2_expbuf(struct dvb_vb2_ctx *ctx, struct dmx_exportbuffer *exp); /** * dvb_vb2_qbuf() - Wrapper to vb2_core_qbuf() for Digital TV buffer handling. * * @ctx: control struct for VB2 handler * @b: &struct dmx_buffer passed from userspace in * order to handle &DMX_QBUF. * * Queue a Digital TV buffer as requested by userspace */ int dvb_vb2_qbuf(struct dvb_vb2_ctx *ctx, struct dmx_buffer *b); /** * dvb_vb2_dqbuf() - Wrapper to vb2_core_dqbuf() for Digital TV * buffer handling. * * @ctx: control struct for VB2 handler * @b: &struct dmx_buffer passed from userspace in * order to handle &DMX_DQBUF. * * Dequeue a Digital TV buffer to the userspace */ int dvb_vb2_dqbuf(struct dvb_vb2_ctx *ctx, struct dmx_buffer *b); /** * dvb_vb2_mmap() - Wrapper to vb2_mmap() for Digital TV buffer handling. * * @ctx: control struct for VB2 handler * @vma: pointer to &struct vm_area_struct with the vma passed * to the mmap file operation handler in the driver. * * map Digital TV video buffers into application address space. */ int dvb_vb2_mmap(struct dvb_vb2_ctx *ctx, struct vm_area_struct *vma); #endif /* _DVB_VB2_H */
