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Diffstat (limited to 'include/media/dvb_vb2.h')
-rw-r--r-- | include/media/dvb_vb2.h | 266 |
1 files changed, 266 insertions, 0 deletions
diff --git a/include/media/dvb_vb2.h b/include/media/dvb_vb2.h new file mode 100644 index 000000000000..dda61af7c4cd --- /dev/null +++ b/include/media/dvb_vb2.h @@ -0,0 +1,266 @@ +/* + * 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. + * @mutex: mutex to serialize vb2 operations. Used by + * vb2 core %wait_prepare and %wait_finish operations. + * @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. + * @name: name of the device type. Currently, it can either be + * "dvr" or "demux_filter". + */ +struct dvb_vb2_ctx { + struct vb2_queue vb_q; + struct mutex mutex; + 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; + char name[DVB_VB2_NAME_MAX + 1]; +}; + +#ifndef DVB_MMAP +static inline int dvb_vb2_init(struct dvb_vb2_ctx *ctx, + const char *name, 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) (0) + +static inline unsigned int 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 + * @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, 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 + */ +int dvb_vb2_fill_buffer(struct dvb_vb2_ctx *ctx, + const unsigned char *src, int len); + +/** + * 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. + */ +unsigned int 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 */ |