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 /* s_config: if set, then it is always called by the v4l2_i2c_new_subdev*
  83         functions after the v4l2_subdev was registered. It is used to pass
  84         platform data to the subdev which can be used during initialization.
  85
  86    init: initialize the sensor registors to some sort of reasonable default
  87         values. Do not use for new drivers and should be removed in existing
  88         drivers.
  89
  90    load_fw: load firmware.
  91
  92    reset: generic reset command. The argument selects which subsystems to
  93         reset. Passing 0 will always reset the whole chip. Do not use for new
  94         drivers without discussing this first on the linux-media mailinglist.
  95         There should be no reason normally to reset a device.
  96
  97    s_gpio: set GPIO pins. Very simple right now, might need to be extended with
  98         a direction argument if needed.
  99  */
 100 struct v4l2_subdev_core_ops {
 101         int (*g_chip_ident)(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip);
 102         int (*log_status)(struct v4l2_subdev *sd);
 103         int (*s_config)(struct v4l2_subdev *sd, int irq, void *platform_data);
 104         int (*init)(struct v4l2_subdev *sd, u32 val);
 105         int (*load_fw)(struct v4l2_subdev *sd);
 106         int (*reset)(struct v4l2_subdev *sd, u32 val);
 107         int (*s_gpio)(struct v4l2_subdev *sd, u32 val);
 108         int (*queryctrl)(struct v4l2_subdev *sd, struct v4l2_queryctrl *qc);
 109         int (*g_ctrl)(struct v4l2_subdev *sd, struct v4l2_control *ctrl);
 110         int (*s_ctrl)(struct v4l2_subdev *sd, struct v4l2_control *ctrl);
 111         int (*g_ext_ctrls)(struct v4l2_subdev *sd, struct v4l2_ext_controls *ctrls);
 112         int (*s_ext_ctrls)(struct v4l2_subdev *sd, struct v4l2_ext_controls *ctrls);
 113         int (*try_ext_ctrls)(struct v4l2_subdev *sd, struct v4l2_ext_controls *ctrls);
 114         int (*querymenu)(struct v4l2_subdev *sd, struct v4l2_querymenu *qm);
 115         int (*s_std)(struct v4l2_subdev *sd, v4l2_std_id norm);
 116         long (*ioctl)(struct v4l2_subdev *sd, unsigned int cmd, void *arg);
 117 #ifdef CONFIG_VIDEO_ADV_DEBUG
 118         int (*g_register)(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg);
 119         int (*s_register)(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg);
 120 #endif
 121 };
 122
 123 /* s_mode: switch the tuner to a specific tuner mode. Replacement of s_radio.
 124
 125    s_radio: v4l device was opened in Radio mode, to be replaced by s_mode.
 126
 127    s_type_addr: sets tuner type and its I2C addr.
 128
 129    s_config: sets tda9887 specific stuff, like port1, port2 and qss
 130
 131    s_standby: puts tuner on powersaving state, disabling it, except for i2c.
 132  */
 133 struct v4l2_subdev_tuner_ops {
 134         int (*s_mode)(struct v4l2_subdev *sd, enum v4l2_tuner_type);
 135         int (*s_radio)(struct v4l2_subdev *sd);
 136         int (*s_frequency)(struct v4l2_subdev *sd, struct v4l2_frequency *freq);
 137         int (*g_frequency)(struct v4l2_subdev *sd, struct v4l2_frequency *freq);
 138         int (*g_tuner)(struct v4l2_subdev *sd, struct v4l2_tuner *vt);
 139         int (*s_tuner)(struct v4l2_subdev *sd, struct v4l2_tuner *vt);
 140         int (*s_type_addr)(struct v4l2_subdev *sd, struct tuner_setup *type);
 141         int (*s_config)(struct v4l2_subdev *sd, const struct v4l2_priv_tun_config *config);
 142         int (*s_standby)(struct v4l2_subdev *sd);
 143 };
 144
 145 /* s_clock_freq: set the frequency (in Hz) of the audio clock output.
 146         Used to slave an audio processor to the video decoder, ensuring that
 147         audio and video remain synchronized. Usual values for the frequency
 148         are 48000, 44100 or 32000 Hz. If the frequency is not supported, then
 149         -EINVAL is returned.
 150
 151    s_i2s_clock_freq: sets I2S speed in bps. This is used to provide a standard
 152         way to select I2S clock used by driving digital audio streams at some
 153         board designs. Usual values for the frequency are 1024000 and 2048000.
 154         If the frequency is not supported, then -EINVAL is returned.
 155
 156    s_routing: used to define the input and/or output pins of an audio chip,
 157         and any additional configuration data.
 158         Never attempt to use user-level input IDs (e.g. Composite, S-Video,
 159         Tuner) at this level. An i2c device shouldn't know about whether an
 160         input pin is connected to a Composite connector, become on another
 161         board or platform it might be connected to something else entirely.
 162         The calling driver is responsible for mapping a user-level input to
 163         the right pins on the i2c device.
 164  */
 165 struct v4l2_subdev_audio_ops {
 166         int (*s_clock_freq)(struct v4l2_subdev *sd, u32 freq);
 167         int (*s_i2s_clock_freq)(struct v4l2_subdev *sd, u32 freq);
 168         int (*s_routing)(struct v4l2_subdev *sd, u32 input, u32 output, u32 config);
 169 };
 170
 171 /*
 172    decode_vbi_line: video decoders that support sliced VBI need to implement
 173         this ioctl. Field p of the v4l2_sliced_vbi_line struct is set to the
 174         start of the VBI data that was generated by the decoder. The driver
 175         then parses the sliced VBI data and sets the other fields in the
 176         struct accordingly. The pointer p is updated to point to the start of
 177         the payload which can be copied verbatim into the data field of the
 178         v4l2_sliced_vbi_data struct. If no valid VBI data was found, then the
 179         type field is set to 0 on return.
 180
 181    s_vbi_data: used to generate VBI signals on a video signal.
 182         v4l2_sliced_vbi_data is filled with the data packets that should be
 183         output. Note that if you set the line field to 0, then that VBI signal
 184         is disabled. If no valid VBI data was found, then the type field is
 185         set to 0 on return.
 186
 187    g_vbi_data: used to obtain the sliced VBI packet from a readback register.
 188         Not all video decoders support this. If no data is available because
 189         the readback register contains invalid or erroneous data -EIO is
 190         returned. Note that you must fill in the 'id' member and the 'field'
 191         member (to determine whether CC data from the first or second field
 192         should be obtained).
 193
 194    s_std_output: set v4l2_std_id for video OUTPUT devices. This is ignored by
 195         video input devices.
 196
 197   s_crystal_freq: sets the frequency of the crystal used to generate the
 198         clocks in Hz. An extra flags field allows device specific configuration
 199         regarding clock frequency dividers, etc. If not used, then set flags
 200         to 0. If the frequency is not supported, then -EINVAL is returned.
 201
 202    g_input_status: get input status. Same as the status field in the v4l2_input
 203         struct.
 204
 205    s_routing: see s_routing in audio_ops, except this version is for video
 206         devices.
 207  */
 208 struct v4l2_subdev_video_ops {
 209         int (*s_routing)(struct v4l2_subdev *sd, u32 input, u32 output, u32 config);
 210         int (*s_crystal_freq)(struct v4l2_subdev *sd, u32 freq, u32 flags);
 211         int (*decode_vbi_line)(struct v4l2_subdev *sd, struct v4l2_decode_vbi_line *vbi_line);
 212         int (*s_vbi_data)(struct v4l2_subdev *sd, const struct v4l2_sliced_vbi_data *vbi_data);
 213         int (*g_vbi_data)(struct v4l2_subdev *sd, struct v4l2_sliced_vbi_data *vbi_data);
 214         int (*g_sliced_vbi_cap)(struct v4l2_subdev *sd, struct v4l2_sliced_vbi_cap *cap);
 215         int (*s_std_output)(struct v4l2_subdev *sd, v4l2_std_id std);
 216         int (*querystd)(struct v4l2_subdev *sd, v4l2_std_id *std);
 217         int (*g_input_status)(struct v4l2_subdev *sd, u32 *status);
 218         int (*s_stream)(struct v4l2_subdev *sd, int enable);
 219         int (*enum_fmt)(struct v4l2_subdev *sd, struct v4l2_fmtdesc *fmtdesc);
 220         int (*g_fmt)(struct v4l2_subdev *sd, struct v4l2_format *fmt);
 221         int (*try_fmt)(struct v4l2_subdev *sd, struct v4l2_format *fmt);
 222         int (*s_fmt)(struct v4l2_subdev *sd, struct v4l2_format *fmt);
 223         int (*g_parm)(struct v4l2_subdev *sd, struct v4l2_streamparm *param);
 224         int (*s_parm)(struct v4l2_subdev *sd, struct v4l2_streamparm *param);
 225         int (*enum_framesizes)(struct v4l2_subdev *sd, struct v4l2_frmsizeenum *fsize);
 226         int (*enum_frameintervals)(struct v4l2_subdev *sd, struct v4l2_frmivalenum *fival);
 227 };
 228
 229 struct v4l2_subdev_ops {
 230         const struct v4l2_subdev_core_ops  *core;
 231         const struct v4l2_subdev_tuner_ops *tuner;
 232         const struct v4l2_subdev_audio_ops *audio;
 233         const struct v4l2_subdev_video_ops *video;
 234 };
 235
 236 #define V4L2_SUBDEV_NAME_SIZE 32
 237
 238 /* Set this flag if this subdev is a i2c device. */
 239 #define V4L2_SUBDEV_FL_IS_I2C (1U << 0)
 240
 241 /* Each instance of a subdev driver should create this struct, either
 242    stand-alone or embedded in a larger struct.
 243  */
 244 struct v4l2_subdev {
 245         struct list_head list;
 246         struct module *owner;
 247         u32 flags;
 248         struct v4l2_device *v4l2_dev;
 249         const struct v4l2_subdev_ops *ops;
 250         /* name must be unique */
 251         char name[V4L2_SUBDEV_NAME_SIZE];
 252         /* can be used to group similar subdevs, value is driver-specific */
 253         u32 grp_id;
 254         /* pointer to private data */
 255         void *priv;
 256 };
 257
 258 static inline void v4l2_set_subdevdata(struct v4l2_subdev *sd, void *p)
 259 {
 260         sd->priv = p;
 261 }
 262
 263 static inline void *v4l2_get_subdevdata(const struct v4l2_subdev *sd)
 264 {
 265         return sd->priv;
 266 }
 267
 268 static inline void v4l2_subdev_init(struct v4l2_subdev *sd,
 269                                         const struct v4l2_subdev_ops *ops)
 270 {
 271         INIT_LIST_HEAD(&sd->list);
 272         /* ops->core MUST be set */
 273         BUG_ON(!ops || !ops->core);
 274         sd->ops = ops;
 275         sd->v4l2_dev = NULL;
 276         sd->flags = 0;
 277         sd->name[0] = '\0';
 278         sd->grp_id = 0;
 279         sd->priv = NULL;
 280 }
 281
 282 /* Call an ops of a v4l2_subdev, doing the right checks against
 283    NULL pointers.
 284
 285    Example: err = v4l2_subdev_call(sd, core, g_chip_ident, &chip);
 286  */
 287 #define v4l2_subdev_call(sd, o, f, args...)                             \
 288         (!(sd) ? -ENODEV : (((sd) && (sd)->ops->o && (sd)->ops->o->f) ? \
 289                 (sd)->ops->o->f((sd) , ##args) : -ENOIOCTLCMD))
 290
 291 /* Send a notification to v4l2_device. */
 292 #define v4l2_subdev_notify(sd, notification, arg)                          \
 293         ((!(sd) || !(sd)->v4l2_dev || !(sd)->v4l2_dev->notify) ? -ENODEV : \
 294          (sd)->v4l2_dev->notify((sd), (notification), (arg)))
 295
 296 #endif