1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * v4l2-dv-timings - Internal header with dv-timings helper functions
4 *
5 * Copyright 2013 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
6 */
7
8 #ifndef __V4L2_DV_TIMINGS_H
9 #define __V4L2_DV_TIMINGS_H
10
11 #include <linux/videodev2.h>
12
13 /**
14 * v4l2_calc_timeperframe - helper function to calculate timeperframe based
15 * v4l2_dv_timings fields.
16 * @t: Timings for the video mode.
17 *
18 * Calculates the expected timeperframe using the pixel clock value and
19 * horizontal/vertical measures. This means that v4l2_dv_timings structure
20 * must be correctly and fully filled.
21 */
22 struct v4l2_fract v4l2_calc_timeperframe(const struct v4l2_dv_timings *t);
23
24 /*
25 * v4l2_dv_timings_presets: list of all dv_timings presets.
26 */
27 extern const struct v4l2_dv_timings v4l2_dv_timings_presets[];
28
29 /**
30 * typedef v4l2_check_dv_timings_fnc - timings check callback
31 *
32 * @t: the v4l2_dv_timings struct.
33 * @handle: a handle from the driver.
34 *
35 * Returns true if the given timings are valid.
36 */
37 typedef bool v4l2_check_dv_timings_fnc(const struct v4l2_dv_timings *t, void *handle);
38
39 /**
40 * v4l2_valid_dv_timings() - are these timings valid?
41 *
42 * @t: the v4l2_dv_timings struct.
43 * @cap: the v4l2_dv_timings_cap capabilities.
44 * @fnc: callback to check if this timing is OK. May be NULL.
45 * @fnc_handle: a handle that is passed on to @fnc.
46 *
47 * Returns true if the given dv_timings struct is supported by the
48 * hardware capabilities and the callback function (if non-NULL), returns
49 * false otherwise.
50 */
51 bool v4l2_valid_dv_timings(const struct v4l2_dv_timings *t,
52 const struct v4l2_dv_timings_cap *cap,
53 v4l2_check_dv_timings_fnc fnc,
54 void *fnc_handle);
55
56 /**
57 * v4l2_enum_dv_timings_cap() - Helper function to enumerate possible DV
58 * timings based on capabilities
59 *
60 * @t: the v4l2_enum_dv_timings struct.
61 * @cap: the v4l2_dv_timings_cap capabilities.
62 * @fnc: callback to check if this timing is OK. May be NULL.
63 * @fnc_handle: a handle that is passed on to @fnc.
64 *
65 * This enumerates dv_timings using the full list of possible CEA-861 and DMT
66 * timings, filtering out any timings that are not supported based on the
67 * hardware capabilities and the callback function (if non-NULL).
68 *
69 * If a valid timing for the given index is found, it will fill in @t and
70 * return 0, otherwise it returns -EINVAL.
71 */
72 int v4l2_enum_dv_timings_cap(struct v4l2_enum_dv_timings *t,
73 const struct v4l2_dv_timings_cap *cap,
74 v4l2_check_dv_timings_fnc fnc,
75 void *fnc_handle);
76
77 /**
78 * v4l2_find_dv_timings_cap() - Find the closest timings struct
79 *
80 * @t: the v4l2_enum_dv_timings struct.
81 * @cap: the v4l2_dv_timings_cap capabilities.
82 * @pclock_delta: maximum delta between t->pixelclock and the timing struct
83 * under consideration.
84 * @fnc: callback to check if a given timings struct is OK. May be NULL.
85 * @fnc_handle: a handle that is passed on to @fnc.
86 *
87 * This function tries to map the given timings to an entry in the
88 * full list of possible CEA-861 and DMT timings, filtering out any timings
89 * that are not supported based on the hardware capabilities and the callback
90 * function (if non-NULL).
91 *
92 * On success it will fill in @t with the found timings and it returns true.
93 * On failure it will return false.
94 */
95 bool v4l2_find_dv_timings_cap(struct v4l2_dv_timings *t,
96 const struct v4l2_dv_timings_cap *cap,
97 unsigned pclock_delta,
98 v4l2_check_dv_timings_fnc fnc,
99 void *fnc_handle);
100
101 /**
102 * v4l2_find_dv_timings_cea861_vic() - find timings based on CEA-861 VIC
103 * @t: the timings data.
104 * @vic: CEA-861 VIC code
105 *
106 * On success it will fill in @t with the found timings and it returns true.
107 * On failure it will return false.
108 */
109 bool v4l2_find_dv_timings_cea861_vic(struct v4l2_dv_timings *t, u8 vic);
110
111 /**
112 * v4l2_match_dv_timings() - do two timings match?
113 *
114 * @measured: the measured timings data.
115 * @standard: the timings according to the standard.
116 * @pclock_delta: maximum delta in Hz between standard->pixelclock and
117 * the measured timings.
118 * @match_reduced_fps: if true, then fail if V4L2_DV_FL_REDUCED_FPS does not
119 * match.
120 *
121 * Returns true if the two timings match, returns false otherwise.
122 */
123 bool v4l2_match_dv_timings(const struct v4l2_dv_timings *measured,
124 const struct v4l2_dv_timings *standard,
125 unsigned pclock_delta, bool match_reduced_fps);
126
127 /**
128 * v4l2_print_dv_timings() - log the contents of a dv_timings struct
129 * @dev_prefix:device prefix for each log line.
130 * @prefix: additional prefix for each log line, may be NULL.
131 * @t: the timings data.
132 * @detailed: if true, give a detailed log.
133 */
134 void v4l2_print_dv_timings(const char *dev_prefix, const char *prefix,
135 const struct v4l2_dv_timings *t, bool detailed);
136
137 /**
138 * v4l2_detect_cvt - detect if the given timings follow the CVT standard
139 *
140 * @frame_height: the total height of the frame (including blanking) in lines.
141 * @hfreq: the horizontal frequency in Hz.
142 * @vsync: the height of the vertical sync in lines.
143 * @active_width: active width of image (does not include blanking). This
144 * information is needed only in case of version 2 of reduced blanking.
145 * In other cases, this parameter does not have any effect on timings.
146 * @polarities: the horizontal and vertical polarities (same as struct
147 * v4l2_bt_timings polarities).
148 * @interlaced: if this flag is true, it indicates interlaced format
149 * @fmt: the resulting timings.
150 *
151 * This function will attempt to detect if the given values correspond to a
152 * valid CVT format. If so, then it will return true, and fmt will be filled
153 * in with the found CVT timings.
154 */
155 bool v4l2_detect_cvt(unsigned frame_height, unsigned hfreq, unsigned vsync,
156 unsigned active_width, u32 polarities, bool interlaced,
157 struct v4l2_dv_timings *fmt);
158
159 /**
160 * v4l2_detect_gtf - detect if the given timings follow the GTF standard
161 *
162 * @frame_height: the total height of the frame (including blanking) in lines.
163 * @hfreq: the horizontal frequency in Hz.
164 * @vsync: the height of the vertical sync in lines.
165 * @polarities: the horizontal and vertical polarities (same as struct
166 * v4l2_bt_timings polarities).
167 * @interlaced: if this flag is true, it indicates interlaced format
168 * @aspect: preferred aspect ratio. GTF has no method of determining the
169 * aspect ratio in order to derive the image width from the
170 * image height, so it has to be passed explicitly. Usually
171 * the native screen aspect ratio is used for this. If it
172 * is not filled in correctly, then 16:9 will be assumed.
173 * @fmt: the resulting timings.
174 *
175 * This function will attempt to detect if the given values correspond to a
176 * valid GTF format. If so, then it will return true, and fmt will be filled
177 * in with the found GTF timings.
178 */
179 bool v4l2_detect_gtf(unsigned frame_height, unsigned hfreq, unsigned vsync,
180 u32 polarities, bool interlaced, struct v4l2_fract aspect,
181 struct v4l2_dv_timings *fmt);
182
183 /**
184 * v4l2_calc_aspect_ratio - calculate the aspect ratio based on bytes
185 * 0x15 and 0x16 from the EDID.
186 *
187 * @hor_landscape: byte 0x15 from the EDID.
188 * @vert_portrait: byte 0x16 from the EDID.
189 *
190 * Determines the aspect ratio from the EDID.
191 * See VESA Enhanced EDID standard, release A, rev 2, section 3.6.2:
192 * "Horizontal and Vertical Screen Size or Aspect Ratio"
193 */
194 struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait);
195
196 /**
197 * v4l2_dv_timings_aspect_ratio - calculate the aspect ratio based on the
198 * v4l2_dv_timings information.
199 *
200 * @t: the timings data.
201 */
202 struct v4l2_fract v4l2_dv_timings_aspect_ratio(const struct v4l2_dv_timings *t);
203
204 /**
205 * can_reduce_fps - check if conditions for reduced fps are true.
206 * @bt: v4l2 timing structure
207 *
208 * For different timings reduced fps is allowed if the following conditions
209 * are met:
210 *
211 * - For CVT timings: if reduced blanking v2 (vsync == 8) is true.
212 * - For CEA861 timings: if %V4L2_DV_FL_CAN_REDUCE_FPS flag is true.
213 */
can_reduce_fps(struct v4l2_bt_timings * bt)214 static inline bool can_reduce_fps(struct v4l2_bt_timings *bt)
215 {
216 if ((bt->standards & V4L2_DV_BT_STD_CVT) && (bt->vsync == 8))
217 return true;
218
219 if ((bt->standards & V4L2_DV_BT_STD_CEA861) &&
220 (bt->flags & V4L2_DV_FL_CAN_REDUCE_FPS))
221 return true;
222
223 return false;
224 }
225
226 /**
227 * struct v4l2_hdmi_colorimetry - describes the HDMI colorimetry information
228 * @colorspace: enum v4l2_colorspace, the colorspace
229 * @ycbcr_enc: enum v4l2_ycbcr_encoding, Y'CbCr encoding
230 * @quantization: enum v4l2_quantization, colorspace quantization
231 * @xfer_func: enum v4l2_xfer_func, colorspace transfer function
232 */
233 struct v4l2_hdmi_colorimetry {
234 enum v4l2_colorspace colorspace;
235 enum v4l2_ycbcr_encoding ycbcr_enc;
236 enum v4l2_quantization quantization;
237 enum v4l2_xfer_func xfer_func;
238 };
239
240 struct hdmi_avi_infoframe;
241 struct hdmi_vendor_infoframe;
242
243 struct v4l2_hdmi_colorimetry
244 v4l2_hdmi_rx_colorimetry(const struct hdmi_avi_infoframe *avi,
245 const struct hdmi_vendor_infoframe *hdmi,
246 unsigned int height);
247
248 u16 v4l2_get_edid_phys_addr(const u8 *edid, unsigned int size,
249 unsigned int *offset);
250 void v4l2_set_edid_phys_addr(u8 *edid, unsigned int size, u16 phys_addr);
251 u16 v4l2_phys_addr_for_input(u16 phys_addr, u8 input);
252 int v4l2_phys_addr_validate(u16 phys_addr, u16 *parent, u16 *port);
253
254 #endif
255