xref: /openbmc/linux/include/media/v4l2-subdev.h (revision 4b2a108c)
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
297