xref: /openbmc/linux/include/media/v4l2-subdev.h (revision b04b4f78)
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 /* Each instance of a subdev driver should create this struct, either
234    stand-alone or embedded in a larger struct.
235  */
236 struct v4l2_subdev {
237 	struct list_head list;
238 	struct module *owner;
239 	struct v4l2_device *v4l2_dev;
240 	const struct v4l2_subdev_ops *ops;
241 	/* name must be unique */
242 	char name[V4L2_SUBDEV_NAME_SIZE];
243 	/* can be used to group similar subdevs, value is driver-specific */
244 	u32 grp_id;
245 	/* pointer to private data */
246 	void *priv;
247 };
248 
249 static inline void v4l2_set_subdevdata(struct v4l2_subdev *sd, void *p)
250 {
251 	sd->priv = p;
252 }
253 
254 static inline void *v4l2_get_subdevdata(const struct v4l2_subdev *sd)
255 {
256 	return sd->priv;
257 }
258 
259 static inline void v4l2_subdev_init(struct v4l2_subdev *sd,
260 					const struct v4l2_subdev_ops *ops)
261 {
262 	INIT_LIST_HEAD(&sd->list);
263 	/* ops->core MUST be set */
264 	BUG_ON(!ops || !ops->core);
265 	sd->ops = ops;
266 	sd->v4l2_dev = NULL;
267 	sd->name[0] = '\0';
268 	sd->grp_id = 0;
269 	sd->priv = NULL;
270 }
271 
272 /* Call an ops of a v4l2_subdev, doing the right checks against
273    NULL pointers.
274 
275    Example: err = v4l2_subdev_call(sd, core, g_chip_ident, &chip);
276  */
277 #define v4l2_subdev_call(sd, o, f, args...)				\
278 	(!(sd) ? -ENODEV : (((sd) && (sd)->ops->o && (sd)->ops->o->f) ?	\
279 		(sd)->ops->o->f((sd) , ##args) : -ENOIOCTLCMD))
280 
281 /* Send a notification to v4l2_device. */
282 #define v4l2_subdev_notify(sd, notification, arg)			   \
283 	((!(sd) || !(sd)->v4l2_dev || !(sd)->v4l2_dev->notify) ? -ENODEV : \
284 	 (sd)->v4l2_dev->notify((sd), (notification), (arg)))
285 
286 #endif
287