include/media/v4l2-dv-timings.h

   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/debugfs.h>
  12 #include <linux/videodev2.h>
  13
  14 /**
  15  * v4l2_calc_timeperframe - helper function to calculate timeperframe based
  16  *      v4l2_dv_timings fields.
  17  * @t: Timings for the video mode.
  18  *
  19  * Calculates the expected timeperframe using the pixel clock value and
  20  * horizontal/vertical measures. This means that v4l2_dv_timings structure
  21  * must be correctly and fully filled.
  22  */
  23 struct v4l2_fract v4l2_calc_timeperframe(const struct v4l2_dv_timings *t);
  24
  25 /*
  26  * v4l2_dv_timings_presets: list of all dv_timings presets.
  27  */
  28 extern const struct v4l2_dv_timings v4l2_dv_timings_presets[];
  29
  30 /**
  31  * typedef v4l2_check_dv_timings_fnc - timings check callback
  32  *
  33  * @t: the v4l2_dv_timings struct.
  34  * @handle: a handle from the driver.
  35  *
  36  * Returns true if the given timings are valid.
  37  */
  38 typedef bool v4l2_check_dv_timings_fnc(const struct v4l2_dv_timings *t, void *handle);
  39
  40 /**
  41  * v4l2_valid_dv_timings() - are these timings valid?
  42  *
  43  * @t:    the v4l2_dv_timings struct.
  44  * @cap: the v4l2_dv_timings_cap capabilities.
  45  * @fnc: callback to check if this timing is OK. May be NULL.
  46  * @fnc_handle: a handle that is passed on to @fnc.
  47  *
  48  * Returns true if the given dv_timings struct is supported by the
  49  * hardware capabilities and the callback function (if non-NULL), returns
  50  * false otherwise.
  51  */
  52 bool v4l2_valid_dv_timings(const struct v4l2_dv_timings *t,
  53                            const struct v4l2_dv_timings_cap *cap,
  54                            v4l2_check_dv_timings_fnc fnc,
  55                            void *fnc_handle);
  56
  57 /**
  58  * v4l2_enum_dv_timings_cap() - Helper function to enumerate possible DV
  59  *       timings based on capabilities
  60  *
  61  * @t:    the v4l2_enum_dv_timings struct.
  62  * @cap: the v4l2_dv_timings_cap capabilities.
  63  * @fnc: callback to check if this timing is OK. May be NULL.
  64  * @fnc_handle: a handle that is passed on to @fnc.
  65  *
  66  * This enumerates dv_timings using the full list of possible CEA-861 and DMT
  67  * timings, filtering out any timings that are not supported based on the
  68  * hardware capabilities and the callback function (if non-NULL).
  69  *
  70  * If a valid timing for the given index is found, it will fill in @t and
  71  * return 0, otherwise it returns -EINVAL.
  72  */
  73 int v4l2_enum_dv_timings_cap(struct v4l2_enum_dv_timings *t,
  74                              const struct v4l2_dv_timings_cap *cap,
  75                              v4l2_check_dv_timings_fnc fnc,
  76                              void *fnc_handle);
  77
  78 /**
  79  * v4l2_find_dv_timings_cap() - Find the closest timings struct
  80  *
  81  * @t:    the v4l2_enum_dv_timings struct.
  82  * @cap: the v4l2_dv_timings_cap capabilities.
  83  * @pclock_delta: maximum delta between t->pixelclock and the timing struct
  84  *              under consideration.
  85  * @fnc: callback to check if a given timings struct is OK. May be NULL.
  86  * @fnc_handle: a handle that is passed on to @fnc.
  87  *
  88  * This function tries to map the given timings to an entry in the
  89  * full list of possible CEA-861 and DMT timings, filtering out any timings
  90  * that are not supported based on the hardware capabilities and the callback
  91  * function (if non-NULL).
  92  *
  93  * On success it will fill in @t with the found timings and it returns true.
  94  * On failure it will return false.
  95  */
  96 bool v4l2_find_dv_timings_cap(struct v4l2_dv_timings *t,
  97                               const struct v4l2_dv_timings_cap *cap,
  98                               unsigned pclock_delta,
  99                               v4l2_check_dv_timings_fnc fnc,
 100                               void *fnc_handle);
 101
 102 /**
 103  * v4l2_find_dv_timings_cea861_vic() - find timings based on CEA-861 VIC
 104  * @t:          the timings data.
 105  * @vic:        CEA-861 VIC code
 106  *
 107  * On success it will fill in @t with the found timings and it returns true.
 108  * On failure it will return false.
 109  */
 110 bool v4l2_find_dv_timings_cea861_vic(struct v4l2_dv_timings *t, u8 vic);
 111
 112 /**
 113  * v4l2_match_dv_timings() - do two timings match?
 114  *
 115  * @measured:     the measured timings data.
 116  * @standard:     the timings according to the standard.
 117  * @pclock_delta: maximum delta in Hz between standard->pixelclock and
 118  *              the measured timings.
 119  * @match_reduced_fps: if true, then fail if V4L2_DV_FL_REDUCED_FPS does not
 120  * match.
 121  *
 122  * Returns true if the two timings match, returns false otherwise.
 123  */
 124 bool v4l2_match_dv_timings(const struct v4l2_dv_timings *measured,
 125                            const struct v4l2_dv_timings *standard,
 126                            unsigned pclock_delta, bool match_reduced_fps);
 127
 128 /**
 129  * v4l2_print_dv_timings() - log the contents of a dv_timings struct
 130  * @dev_prefix:device prefix for each log line.
 131  * @prefix:     additional prefix for each log line, may be NULL.
 132  * @t:          the timings data.
 133  * @detailed:   if true, give a detailed log.
 134  */
 135 void v4l2_print_dv_timings(const char *dev_prefix, const char *prefix,
 136                            const struct v4l2_dv_timings *t, bool detailed);
 137
 138 /**
 139  * v4l2_detect_cvt - detect if the given timings follow the CVT standard
 140  *
 141  * @frame_height: the total height of the frame (including blanking) in lines.
 142  * @hfreq: the horizontal frequency in Hz.
 143  * @vsync: the height of the vertical sync in lines.
 144  * @active_width: active width of image (does not include blanking). This
 145  * information is needed only in case of version 2 of reduced blanking.
 146  * In other cases, this parameter does not have any effect on timings.
 147  * @polarities: the horizontal and vertical polarities (same as struct
 148  *              v4l2_bt_timings polarities).
 149  * @interlaced: if this flag is true, it indicates interlaced format
 150  * @cap: the v4l2_dv_timings_cap capabilities.
 151  * @fmt: the resulting timings.
 152  *
 153  * This function will attempt to detect if the given values correspond to a
 154  * valid CVT format. If so, then it will return true, and fmt will be filled
 155  * in with the found CVT timings.
 156  */
 157 bool v4l2_detect_cvt(unsigned int frame_height, unsigned int hfreq,
 158                      unsigned int vsync, unsigned int active_width,
 159                      u32 polarities, bool interlaced,
 160                      const struct v4l2_dv_timings_cap *cap,
 161                      struct v4l2_dv_timings *fmt);
 162
 163 /**
 164  * v4l2_detect_gtf - detect if the given timings follow the GTF standard
 165  *
 166  * @frame_height: the total height of the frame (including blanking) in lines.
 167  * @hfreq: the horizontal frequency in Hz.
 168  * @vsync: the height of the vertical sync in lines.
 169  * @polarities: the horizontal and vertical polarities (same as struct
 170  *              v4l2_bt_timings polarities).
 171  * @interlaced: if this flag is true, it indicates interlaced format
 172  * @aspect: preferred aspect ratio. GTF has no method of determining the
 173  *              aspect ratio in order to derive the image width from the
 174  *              image height, so it has to be passed explicitly. Usually
 175  *              the native screen aspect ratio is used for this. If it
 176  *              is not filled in correctly, then 16:9 will be assumed.
 177  * @cap: the v4l2_dv_timings_cap capabilities.
 178  * @fmt: the resulting timings.
 179  *
 180  * This function will attempt to detect if the given values correspond to a
 181  * valid GTF format. If so, then it will return true, and fmt will be filled
 182  * in with the found GTF timings.
 183  */
 184 bool v4l2_detect_gtf(unsigned int frame_height, unsigned int hfreq,
 185                      unsigned int vsync, u32 polarities, bool interlaced,
 186                      struct v4l2_fract aspect,
 187                      const struct v4l2_dv_timings_cap *cap,
 188                      struct v4l2_dv_timings *fmt);
 189
 190 /**
 191  * v4l2_calc_aspect_ratio - calculate the aspect ratio based on bytes
 192  *      0x15 and 0x16 from the EDID.
 193  *
 194  * @hor_landscape: byte 0x15 from the EDID.
 195  * @vert_portrait: byte 0x16 from the EDID.
 196  *
 197  * Determines the aspect ratio from the EDID.
 198  * See VESA Enhanced EDID standard, release A, rev 2, section 3.6.2:
 199  * "Horizontal and Vertical Screen Size or Aspect Ratio"
 200  */
 201 struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait);
 202
 203 /**
 204  * v4l2_dv_timings_aspect_ratio - calculate the aspect ratio based on the
 205  *      v4l2_dv_timings information.
 206  *
 207  * @t: the timings data.
 208  */
 209 struct v4l2_fract v4l2_dv_timings_aspect_ratio(const struct v4l2_dv_timings *t);
 210
 211 /**
 212  * can_reduce_fps - check if conditions for reduced fps are true.
 213  * @bt: v4l2 timing structure
 214  *
 215  * For different timings reduced fps is allowed if the following conditions
 216  * are met:
 217  *
 218  *   - For CVT timings: if reduced blanking v2 (vsync == 8) is true.
 219  *   - For CEA861 timings: if %V4L2_DV_FL_CAN_REDUCE_FPS flag is true.
 220  */
 221 static inline  bool can_reduce_fps(struct v4l2_bt_timings *bt)
 222 {
 223         if ((bt->standards & V4L2_DV_BT_STD_CVT) && (bt->vsync == 8))
 224                 return true;
 225
 226         if ((bt->standards & V4L2_DV_BT_STD_CEA861) &&
 227             (bt->flags & V4L2_DV_FL_CAN_REDUCE_FPS))
 228                 return true;
 229
 230         return false;
 231 }
 232
 233 /**
 234  * struct v4l2_hdmi_colorimetry - describes the HDMI colorimetry information
 235  * @colorspace:         enum v4l2_colorspace, the colorspace
 236  * @ycbcr_enc:          enum v4l2_ycbcr_encoding, Y'CbCr encoding
 237  * @quantization:       enum v4l2_quantization, colorspace quantization
 238  * @xfer_func:          enum v4l2_xfer_func, colorspace transfer function
 239  */
 240 struct v4l2_hdmi_colorimetry {
 241         enum v4l2_colorspace colorspace;
 242         enum v4l2_ycbcr_encoding ycbcr_enc;
 243         enum v4l2_quantization quantization;
 244         enum v4l2_xfer_func xfer_func;
 245 };
 246
 247 struct hdmi_avi_infoframe;
 248 struct hdmi_vendor_infoframe;
 249
 250 struct v4l2_hdmi_colorimetry
 251 v4l2_hdmi_rx_colorimetry(const struct hdmi_avi_infoframe *avi,
 252                          const struct hdmi_vendor_infoframe *hdmi,
 253                          unsigned int height);
 254
 255 u16 v4l2_get_edid_phys_addr(const u8 *edid, unsigned int size,
 256                             unsigned int *offset);
 257 void v4l2_set_edid_phys_addr(u8 *edid, unsigned int size, u16 phys_addr);
 258 u16 v4l2_phys_addr_for_input(u16 phys_addr, u8 input);
 259 int v4l2_phys_addr_validate(u16 phys_addr, u16 *parent, u16 *port);
 260
 261 /* Add support for exporting InfoFrames to debugfs */
 262
 263 /*
 264  * HDMI InfoFrames start with a 3 byte header, then a checksum,
 265  * followed by the actual IF payload.
 266  *
 267  * The payload length is limited to 30 bytes according to the HDMI spec,
 268  * but since the length is encoded in 5 bits, it can be 31 bytes theoretically.
 269  * So set the max length as 31 + 3 (header) + 1 (checksum) = 35.
 270  */
 271 #define V4L2_DEBUGFS_IF_MAX_LEN (35)
 272
 273 #define V4L2_DEBUGFS_IF_AVI     BIT(0)
 274 #define V4L2_DEBUGFS_IF_AUDIO   BIT(1)
 275 #define V4L2_DEBUGFS_IF_SPD     BIT(2)
 276 #define V4L2_DEBUGFS_IF_HDMI    BIT(3)
 277
 278 typedef ssize_t (*v4l2_debugfs_if_read_t)(u32 type, void *priv,
 279                                           struct file *filp, char __user *ubuf,
 280                                           size_t count, loff_t *ppos);
 281
 282 struct v4l2_debugfs_if {
 283         struct dentry *if_dir;
 284         void *priv;
 285
 286         v4l2_debugfs_if_read_t if_read;
 287 };
 288
 289 #ifdef CONFIG_DEBUG_FS
 290 struct v4l2_debugfs_if *v4l2_debugfs_if_alloc(struct dentry *root, u32 if_types,
 291                                               void *priv,
 292                                               v4l2_debugfs_if_read_t if_read);
 293 void v4l2_debugfs_if_free(struct v4l2_debugfs_if *infoframes);
 294 #else
 295 static inline
 296 struct v4l2_debugfs_if *v4l2_debugfs_if_alloc(struct dentry *root, u32 if_types,
 297                                               void *priv,
 298                                               v4l2_debugfs_if_read_t if_read)
 299 {
 300         return NULL;
 301 }
 302
 303 static inline void v4l2_debugfs_if_free(struct v4l2_debugfs_if *infoframes)
 304 {
 305 }
 306 #endif
 307
 308 #endif