include/media/v4l2-subdev.h

   1 /*
   2     V4L2 sub-device support header.
   3
   4     Copyright (C) 2008  Hans Verkuil <hverkuil@xs4all.nl>
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #ifndef _V4L2_SUBDEV_H
  22 #define _V4L2_SUBDEV_H
  23
  24 #include <media/v4l2-common.h>
  25
  26 struct v4l2_device;
  27 struct v4l2_subdev;
  28 struct tuner_setup;
  29
  30 /* decode_vbi_line */
  31 struct v4l2_decode_vbi_line {
  32         u32 is_second_field;    /* Set to 0 for the first (odd) field,
  33                                    set to 1 for the second (even) field. */
  34         u8 *p;                  /* Pointer to the sliced VBI data from the decoder.
  35                                    On exit points to the start of the payload. */
  36         u32 line;               /* Line number of the sliced VBI data (1-23) */
  37         u32 type;               /* VBI service type (V4L2_SLICED_*). 0 if no service found */
  38 };
  39
  40 /* Sub-devices are devices that are connected somehow to the main bridge
  41    device. These devices are usually audio/video muxers/encoders/decoders or
  42    sensors and webcam controllers.
  43
  44    Usually these devices are controlled through an i2c bus, but other busses
  45    may also be used.
  46
  47    The v4l2_subdev struct provides a way of accessing these devices in a
  48    generic manner. Most operations that these sub-devices support fall in
  49    a few categories: core ops, audio ops, video ops and tuner ops.
  50
  51    More categories can be added if needed, although this should remain a
  52    limited set (no more than approx. 8 categories).
  53
  54    Each category has its own set of ops that subdev drivers can implement.
  55
  56    A subdev driver can leave the pointer to the category ops NULL if
  57    it does not implement them (e.g. an audio subdev will generally not
  58    implement the video category ops). The exception is the core category:
  59    this must always be present.
  60
  61    These ops are all used internally so it is no problem to change, remove
  62    or add ops or move ops from one to another category. Currently these
  63    ops are based on the original ioctls, but since ops are not limited to
  64    one argument there is room for improvement here once all i2c subdev
  65    drivers are converted to use these ops.
  66  */
  67
  68 /* Core ops: it is highly recommended to implement at least these ops:
  69
  70    g_chip_ident
  71    log_status
  72    g_register
  73    s_register
  74
  75    This provides basic debugging support.
  76
  77    The ioctl ops is meant for generic ioctl-like commands. Depending on
  78    the use-case it might be better to use subdev-specific ops (currently
  79    not yet implemented) since ops provide proper type-checking.
  80  */
  81
  82 /* init: initialize the sensor registors to some sort of reasonable default
  83         values. Do not use for new drivers and should be removed in existing
  84         drivers.
  85
  86    load_fw: load firmware.
  87
  88    reset: generic reset command. The argument selects which subsystems to
  89         reset. Passing 0 will always reset the whole chip. Do not use for new
  90         drivers without discussing this first on the linux-media mailinglist.
  91         There should be no reason normally to reset a device.
  92
  93    s_gpio: set GPIO pins. Very simple right now, might need to be extended with
  94         a direction argument if needed.
  95  */
  96 struct v4l2_subdev_core_ops {
  97         int (*g_chip_ident)(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip);
  98         int (*log_status)(struct v4l2_subdev *sd);
  99         int (*init)(struct v4l2_subdev *sd, u32 val);
 100         int (*load_fw)(struct v4l2_subdev *sd);
 101         int (*reset)(struct v4l2_subdev *sd, u32 val);
 102         int (*s_gpio)(struct v4l2_subdev *sd, u32 val);
 103         int (*queryctrl)(struct v4l2_subdev *sd, struct v4l2_queryctrl *qc);
 104         int (*g_ctrl)(struct v4l2_subdev *sd, struct v4l2_control *ctrl);
 105         int (*s_ctrl)(struct v4l2_subdev *sd, struct v4l2_control *ctrl);
 106         int (*g_ext_ctrls)(struct v4l2_subdev *sd, struct v4l2_ext_controls *ctrls);
 107         int (*s_ext_ctrls)(struct v4l2_subdev *sd, struct v4l2_ext_controls *ctrls);
 108         int (*try_ext_ctrls)(struct v4l2_subdev *sd, struct v4l2_ext_controls *ctrls);
 109         int (*querymenu)(struct v4l2_subdev *sd, struct v4l2_querymenu *qm);
 110         int (*s_std)(struct v4l2_subdev *sd, v4l2_std_id norm);
 111         long (*ioctl)(struct v4l2_subdev *sd, unsigned int cmd, void *arg);
 112 #ifdef CONFIG_VIDEO_ADV_DEBUG
 113         int (*g_register)(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg);
 114         int (*s_register)(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg);
 115 #endif
 116 };
 117
 118 /* s_mode: switch the tuner to a specific tuner mode. Replacement of s_radio.
 119
 120    s_radio: v4l device was opened in Radio mode, to be replaced by s_mode.
 121
 122    s_type_addr: sets tuner type and its I2C addr.
 123
 124    s_config: sets tda9887 specific stuff, like port1, port2 and qss
 125
 126    s_standby: puts tuner on powersaving state, disabling it, except for i2c.
 127  */
 128 struct v4l2_subdev_tuner_ops {
 129         int (*s_mode)(struct v4l2_subdev *sd, enum v4l2_tuner_type);
 130         int (*s_radio)(struct v4l2_subdev *sd);
 131         int (*s_frequency)(struct v4l2_subdev *sd, struct v4l2_frequency *freq);
 132         int (*g_frequency)(struct v4l2_subdev *sd, struct v4l2_frequency *freq);
 133         int (*g_tuner)(struct v4l2_subdev *sd, struct v4l2_tuner *vt);
 134         int (*s_tuner)(struct v4l2_subdev *sd, struct v4l2_tuner *vt);
 135         int (*s_type_addr)(struct v4l2_subdev *sd, struct tuner_setup *type);
 136         int (*s_config)(struct v4l2_subdev *sd, const struct v4l2_priv_tun_config *config);
 137         int (*s_standby)(struct v4l2_subdev *sd);
 138 };
 139
 140 /* s_clock_freq: set the frequency (in Hz) of the audio clock output.
 141         Used to slave an audio processor to the video decoder, ensuring that
 142         audio and video remain synchronized. Usual values for the frequency
 143         are 48000, 44100 or 32000 Hz. If the frequency is not supported, then
 144         -EINVAL is returned.
 145
 146    s_i2s_clock_freq: sets I2S speed in bps. This is used to provide a standard
 147         way to select I2S clock used by driving digital audio streams at some
 148         board designs. Usual values for the frequency are 1024000 and 2048000.
 149         If the frequency is not supported, then -EINVAL is returned.
 150
 151    s_routing: used to define the input and/or output pins of an audio chip,
 152         and any additional configuration data.
 153         Never attempt to use user-level input IDs (e.g. Composite, S-Video,
 154         Tuner) at this level. An i2c device shouldn't know about whether an
 155         input pin is connected to a Composite connector, become on another
 156         board or platform it might be connected to something else entirely.
 157         The calling driver is responsible for mapping a user-level input to
 158         the right pins on the i2c device.
 159  */
 160 struct v4l2_subdev_audio_ops {
 161         int (*s_clock_freq)(struct v4l2_subdev *sd, u32 freq);
 162         int (*s_i2s_clock_freq)(struct v4l2_subdev *sd, u32 freq);
 163         int (*s_routing)(struct v4l2_subdev *sd, u32 input, u32 output, u32 config);
 164 };
 165
 166 /*
 167    decode_vbi_line: video decoders that support sliced VBI need to implement
 168         this ioctl. Field p of the v4l2_sliced_vbi_line struct is set to the
 169         start of the VBI data that was generated by the decoder. The driver
 170         then parses the sliced VBI data and sets the other fields in the
 171         struct accordingly. The pointer p is updated to point to the start of
 172         the payload which can be copied verbatim into the data field of the
 173         v4l2_sliced_vbi_data struct. If no valid VBI data was found, then the
 174         type field is set to 0 on return.
 175
 176    s_vbi_data: used to generate VBI signals on a video signal.
 177         v4l2_sliced_vbi_data is filled with the data packets that should be
 178         output. Note that if you set the line field to 0, then that VBI signal
 179         is disabled. If no valid VBI data was found, then the type field is
 180         set to 0 on return.
 181
 182    g_vbi_data: used to obtain the sliced VBI packet from a readback register.
 183         Not all video decoders support this. If no data is available because
 184         the readback register contains invalid or erroneous data -EIO is
 185         returned. Note that you must fill in the 'id' member and the 'field'
 186         member (to determine whether CC data from the first or second field
 187         should be obtained).
 188
 189    s_std_output: set v4l2_std_id for video OUTPUT devices. This is ignored by
 190         video input devices.
 191
 192   s_crystal_freq: sets the frequency of the crystal used to generate the
 193         clocks in Hz. An extra flags field allows device specific configuration
 194         regarding clock frequency dividers, etc. If not used, then set flags
 195         to 0. If the frequency is not supported, then -EINVAL is returned.
 196
 197    g_input_status: get input status. Same as the status field in the v4l2_input
 198         struct.
 199
 200    s_routing: see s_routing in audio_ops, except this version is for video
 201         devices.
 202  */
 203 struct v4l2_subdev_video_ops {
 204         int (*s_routing)(struct v4l2_subdev *sd, u32 input, u32 output, u32 config);
 205         int (*s_crystal_freq)(struct v4l2_subdev *sd, u32 freq, u32 flags);
 206         int (*decode_vbi_line)(struct v4l2_subdev *sd, struct v4l2_decode_vbi_line *vbi_line);
 207         int (*s_vbi_data)(struct v4l2_subdev *sd, const struct v4l2_sliced_vbi_data *vbi_data);
 208         int (*g_vbi_data)(struct v4l2_subdev *sd, struct v4l2_sliced_vbi_data *vbi_data);
 209         int (*g_sliced_vbi_cap)(struct v4l2_subdev *sd, struct v4l2_sliced_vbi_cap *cap);
 210         int (*s_std_output)(struct v4l2_subdev *sd, v4l2_std_id std);
 211         int (*querystd)(struct v4l2_subdev *sd, v4l2_std_id *std);
 212         int (*g_input_status)(struct v4l2_subdev *sd, u32 *status);
 213         int (*s_stream)(struct v4l2_subdev *sd, int enable);
 214         int (*enum_fmt)(struct v4l2_subdev *sd, struct v4l2_fmtdesc *fmtdesc);
 215         int (*g_fmt)(struct v4l2_subdev *sd, struct v4l2_format *fmt);
 216         int (*try_fmt)(struct v4l2_subdev *sd, struct v4l2_format *fmt);
 217         int (*s_fmt)(struct v4l2_subdev *sd, struct v4l2_format *fmt);
 218         int (*g_parm)(struct v4l2_subdev *sd, struct v4l2_streamparm *param);
 219         int (*s_parm)(struct v4l2_subdev *sd, struct v4l2_streamparm *param);
 220         int (*enum_framesizes)(struct v4l2_subdev *sd, struct v4l2_frmsizeenum *fsize);
 221         int (*enum_frameintervals)(struct v4l2_subdev *sd, struct v4l2_frmivalenum *fival);
 222 };
 223
 224 struct v4l2_subdev_ops {
 225         const struct v4l2_subdev_core_ops  *core;
 226         const struct v4l2_subdev_tuner_ops *tuner;
 227         const struct v4l2_subdev_audio_ops *audio;
 228         const struct v4l2_subdev_video_ops *video;
 229 };
 230
 231 #define V4L2_SUBDEV_NAME_SIZE 32
 232
 233 /* Set this flag if this subdev is a i2c device. */
 234 #define V4L2_SUBDEV_FL_IS_I2C (1U << 0)
 235
 236 /* Each instance of a subdev driver should create this struct, either
 237    stand-alone or embedded in a larger struct.
 238  */
 239 struct v4l2_subdev {
 240         struct list_head list;
 241         struct module *owner;
 242         u32 flags;
 243         struct v4l2_device *v4l2_dev;
 244         const struct v4l2_subdev_ops *ops;
 245         /* name must be unique */
 246         char name[V4L2_SUBDEV_NAME_SIZE];
 247         /* can be used to group similar subdevs, value is driver-specific */
 248         u32 grp_id;
 249         /* pointer to private data */
 250         void *priv;
 251 };
 252
 253 static inline void v4l2_set_subdevdata(struct v4l2_subdev *sd, void *p)
 254 {
 255         sd->priv = p;
 256 }
 257
 258 static inline void *v4l2_get_subdevdata(const struct v4l2_subdev *sd)
 259 {
 260         return sd->priv;
 261 }
 262
 263 static inline void v4l2_subdev_init(struct v4l2_subdev *sd,
 264                                         const struct v4l2_subdev_ops *ops)
 265 {
 266         INIT_LIST_HEAD(&sd->list);
 267         /* ops->core MUST be set */
 268         BUG_ON(!ops || !ops->core);
 269         sd->ops = ops;
 270         sd->v4l2_dev = NULL;
 271         sd->flags = 0;
 272         sd->name[0] = '\0';
 273         sd->grp_id = 0;
 274         sd->priv = NULL;
 275 }
 276
 277 /* Call an ops of a v4l2_subdev, doing the right checks against
 278    NULL pointers.
 279
 280    Example: err = v4l2_subdev_call(sd, core, g_chip_ident, &chip);
 281  */
 282 #define v4l2_subdev_call(sd, o, f, args...)                             \
 283         (!(sd) ? -ENODEV : (((sd) && (sd)->ops->o && (sd)->ops->o->f) ? \
 284                 (sd)->ops->o->f((sd) , ##args) : -ENOIOCTLCMD))
 285
 286 /* Send a notification to v4l2_device. */
 287 #define v4l2_subdev_notify(sd, notification, arg)                          \
 288         ((!(sd) || !(sd)->v4l2_dev || !(sd)->v4l2_dev->notify) ? -ENODEV : \
 289          (sd)->v4l2_dev->notify((sd), (notification), (arg)))
 290
 291 #endif