1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2/*
3 * Video4Linux2 generic ISP parameters and statistics support
4 *
5 * Copyright (C) 2025 Ideas On Board Oy
6 * Author: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
7 */
8
9#ifndef _UAPI_V4L2_ISP_H_
10#define _UAPI_V4L2_ISP_H_
11
12#include <linux/stddef.h>
13#include <linux/types.h>
14
15/**
16 * enum v4l2_isp_params_version - V4L2 ISP parameters versioning
17 *
18 * @V4L2_ISP_PARAMS_VERSION_V0: First version of the V4L2 ISP parameters format
19 * (for compatibility)
20 * @V4L2_ISP_PARAMS_VERSION_V1: First version of the V4L2 ISP parameters format
21 *
22 * V0 and V1 are identical in order to support drivers compatible with the V4L2
23 * ISP parameters format already upstreamed which use either 0 or 1 as their
24 * versioning identifier. Both V0 and V1 refers to the first version of the
25 * V4L2 ISP parameters format.
26 *
27 * Future revisions of the V4L2 ISP parameters format should start from the
28 * value of 2.
29 */
30enum v4l2_isp_params_version {
31 V4L2_ISP_PARAMS_VERSION_V0 = 0,
32 V4L2_ISP_PARAMS_VERSION_V1
33};
34
35#define V4L2_ISP_PARAMS_FL_BLOCK_DISABLE (1U << 0)
36#define V4L2_ISP_PARAMS_FL_BLOCK_ENABLE (1U << 1)
37
38/*
39 * Reserve the first 8 bits for V4L2_ISP_PARAMS_FL_* flag.
40 *
41 * Driver-specific flags should be defined as:
42 * #define DRIVER_SPECIFIC_FLAG0 ((1U << V4L2_ISP_PARAMS_FL_DRIVER_FLAGS(0))
43 * #define DRIVER_SPECIFIC_FLAG1 ((1U << V4L2_ISP_PARAMS_FL_DRIVER_FLAGS(1))
44 */
45#define V4L2_ISP_PARAMS_FL_DRIVER_FLAGS(n) ((n) + 8)
46
47/**
48 * struct v4l2_isp_params_block_header - V4L2 extensible parameters block header
49 * @type: The parameters block type (driver-specific)
50 * @flags: A bitmask of block flags (driver-specific)
51 * @size: Size (in bytes) of the parameters block, including this header
52 *
53 * This structure represents the common part of all the ISP configuration
54 * blocks. Each parameters block shall embed an instance of this structure type
55 * as its first member, followed by the block-specific configuration data.
56 *
57 * The @type field is an ISP driver-specific value that identifies the block
58 * type. The @size field specifies the size of the parameters block.
59 *
60 * The @flags field is a bitmask of per-block flags V4L2_PARAMS_ISP_FL_* and
61 * driver-specific flags specified by the driver header.
62 */
63struct v4l2_isp_params_block_header {
64 __u16 type;
65 __u16 flags;
66 __u32 size;
67} __attribute__((aligned(8)));
68
69/**
70 * struct v4l2_isp_params_buffer - V4L2 extensible parameters configuration
71 * @version: The parameters buffer version (driver-specific)
72 * @data_size: The configuration data effective size, excluding this header
73 * @data: The configuration data
74 *
75 * This structure contains the configuration parameters of the ISP algorithms,
76 * serialized by userspace into a data buffer. Each configuration parameter
77 * block is represented by a block-specific structure which contains a
78 * :c:type:`v4l2_isp_params_block_header` entry as first member. Userspace
79 * populates the @data buffer with configuration parameters for the blocks that
80 * it intends to configure. As a consequence, the data buffer effective size
81 * changes according to the number of ISP blocks that userspace intends to
82 * configure and is set by userspace in the @data_size field.
83 *
84 * The parameters buffer is versioned by the @version field to allow modifying
85 * and extending its definition. Userspace shall populate the @version field to
86 * inform the driver about the version it intends to use. The driver will parse
87 * and handle the @data buffer according to the data layout specific to the
88 * indicated version and return an error if the desired version is not
89 * supported.
90 *
91 * For each ISP block that userspace wants to configure, a block-specific
92 * structure is appended to the @data buffer, one after the other without gaps
93 * in between. Userspace shall populate the @data_size field with the effective
94 * size, in bytes, of the @data buffer.
95 */
96struct v4l2_isp_params_buffer {
97 __u32 version;
98 __u32 data_size;
99 __u8 data[] __counted_by(data_size);
100};
101
102#endif /* _UAPI_V4L2_ISP_H_ */
103

source code of linux/include/uapi/linux/media/v4l2-isp.h