release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/media/video/sn9c102/sn9c102_sensor.h

   1 /***************************************************************************
   2  * API for image sensors connected to the SN9C1xx PC Camera Controllers    *
   3  *                                                                         *
   4  * Copyright (C) 2004-2007 by Luca Risolia <luca.risolia@studio.unibo.it>  *
   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., 675 Mass Ave, Cambridge, MA 02139, USA.               *
  19  ***************************************************************************/
  20
  21 #ifndef _SN9C102_SENSOR_H_
  22 #define _SN9C102_SENSOR_H_
  23
  24 #include <linux/usb.h>
  25 #include <linux/videodev2.h>
  26 #include <linux/device.h>
  27 #include <linux/stddef.h>
  28 #include <linux/errno.h>
  29 #include <asm/types.h>
  30
  31 struct sn9c102_device;
  32 struct sn9c102_sensor;
  33
  34 /*****************************************************************************/
  35
  36 /*
  37    OVERVIEW.
  38    This is a small interface that allows you to add support for any CCD/CMOS
  39    image sensors connected to the SN9C1XX bridges. The entire API is documented
  40    below. In the most general case, to support a sensor there are three steps
  41    you have to follow:
  42    1) define the main "sn9c102_sensor" structure by setting the basic fields;
  43    2) write a probing function to be called by the core module when the USB
  44       camera is recognized, then add both the USB ids and the name of that
  45       function to the two corresponding tables in sn9c102_devtable.h;
  46    3) implement the methods that you want/need (and fill the rest of the main
  47       structure accordingly).
  48    "sn9c102_pas106b.c" is an example of all this stuff. Remember that you do
  49    NOT need to touch the source code of the core module for the things to work
  50    properly, unless you find bugs or flaws in it. Finally, do not forget to
  51    read the V4L2 API for completeness.
  52 */
  53
  54 /*****************************************************************************/
  55
  56 enum sn9c102_bridge {
  57         BRIDGE_SN9C101 = 0x01,
  58         BRIDGE_SN9C102 = 0x02,
  59         BRIDGE_SN9C103 = 0x04,
  60         BRIDGE_SN9C105 = 0x08,
  61         BRIDGE_SN9C120 = 0x10,
  62 };
  63
  64 /* Return the bridge name */
  65 enum sn9c102_bridge sn9c102_get_bridge(struct sn9c102_device* cam);
  66
  67 /* Return a pointer the sensor struct attached to the camera */
  68 struct sn9c102_sensor* sn9c102_get_sensor(struct sn9c102_device* cam);
  69
  70 /* Identify a device */
  71 extern struct sn9c102_device*
  72 sn9c102_match_id(struct sn9c102_device* cam, const struct usb_device_id *id);
  73
  74 /* Attach a probed sensor to the camera. */
  75 extern void
  76 sn9c102_attach_sensor(struct sn9c102_device* cam,
  77                       const struct sn9c102_sensor* sensor);
  78
  79
  80 /* The "try" I2C I/O versions are used when probing the sensor */
  81 extern int sn9c102_i2c_try_read(struct sn9c102_device*,
  82                                 const struct sn9c102_sensor*, u8 address);
  83
  84 /*
  85    These must be used if and only if the sensor doesn't implement the standard
  86    I2C protocol. There are a number of good reasons why you must use the
  87    single-byte versions of these functions: do not abuse. The first function
  88    writes n bytes, from data0 to datan, to registers 0x09 - 0x09+n of SN9C1XX
  89    chip. The second one programs the registers 0x09 and 0x10 with data0 and
  90    data1, and places the n bytes read from the sensor register table in the
  91    buffer pointed by 'buffer'. Both the functions return -1 on error; the write
  92    version returns 0 on success, while the read version returns the first read
  93    byte.
  94 */
  95 extern int sn9c102_i2c_try_raw_write(struct sn9c102_device* cam,
  96                                      const struct sn9c102_sensor* sensor, u8 n,
  97                                      u8 data0, u8 data1, u8 data2, u8 data3,
  98                                      u8 data4, u8 data5);
  99 extern int sn9c102_i2c_try_raw_read(struct sn9c102_device* cam,
 100                                     const struct sn9c102_sensor* sensor,
 101                                     u8 data0, u8 data1, u8 n, u8 buffer[]);
 102
 103 /* To be used after the sensor struct has been attached to the camera struct */
 104 extern int sn9c102_i2c_write(struct sn9c102_device*, u8 address, u8 value);
 105 extern int sn9c102_i2c_read(struct sn9c102_device*, u8 address);
 106
 107 /* I/O on registers in the bridge. Could be used by the sensor methods too */
 108 extern int sn9c102_read_reg(struct sn9c102_device*, u16 index);
 109 extern int sn9c102_pread_reg(struct sn9c102_device*, u16 index);
 110 extern int sn9c102_write_reg(struct sn9c102_device*, u8 value, u16 index);
 111 extern int sn9c102_write_regs(struct sn9c102_device*, const u8 valreg[][2],
 112                               int count);
 113 /*
 114    Write multiple registers with constant values. For example:
 115    sn9c102_write_const_regs(cam, {0x00, 0x14}, {0x60, 0x17}, {0x0f, 0x18});
 116    Register addresses must be < 256.
 117 */
 118 #define sn9c102_write_const_regs(sn9c102_device, data...)                     \
 119         ({ static const u8 _valreg[][2] = {data};                             \
 120         sn9c102_write_regs(sn9c102_device, _valreg, ARRAY_SIZE(_valreg)); })
 121
 122 /*****************************************************************************/
 123
 124 enum sn9c102_i2c_sysfs_ops {
 125         SN9C102_I2C_READ = 0x01,
 126         SN9C102_I2C_WRITE = 0x02,
 127 };
 128
 129 enum sn9c102_i2c_frequency { /* sensors may support both the frequencies */
 130         SN9C102_I2C_100KHZ = 0x01,
 131         SN9C102_I2C_400KHZ = 0x02,
 132 };
 133
 134 enum sn9c102_i2c_interface {
 135         SN9C102_I2C_2WIRES,
 136         SN9C102_I2C_3WIRES,
 137 };
 138
 139 #define SN9C102_MAX_CTRLS (V4L2_CID_LASTP1-V4L2_CID_BASE+10)
 140
 141 struct sn9c102_sensor {
 142         char name[32], /* sensor name */
 143              maintainer[64]; /* name of the mantainer <email> */
 144
 145         enum sn9c102_bridge supported_bridge; /* supported SN9C1xx bridges */
 146
 147         /* Supported operations through the 'sysfs' interface */
 148         enum sn9c102_i2c_sysfs_ops sysfs_ops;
 149
 150         /*
 151            These sensor capabilities must be provided if the SN9C1XX controller
 152            needs to communicate through the sensor serial interface by using
 153            at least one of the i2c functions available.
 154         */
 155         enum sn9c102_i2c_frequency frequency;
 156         enum sn9c102_i2c_interface interface;
 157
 158         /*
 159            This identifier must be provided if the image sensor implements
 160            the standard I2C protocol.
 161         */
 162         u8 i2c_slave_id; /* reg. 0x09 */
 163
 164         /*
 165            NOTE: Where not noted,most of the functions below are not mandatory.
 166                  Set to null if you do not implement them. If implemented,
 167                  they must return 0 on success, the proper error otherwise.
 168         */
 169
 170         int (*init)(struct sn9c102_device* cam);
 171         /*
 172            This function will be called after the sensor has been attached.
 173            It should be used to initialize the sensor only, but may also
 174            configure part of the SN9C1XX chip if necessary. You don't need to
 175            setup picture settings like brightness, contrast, etc.. here, if
 176            the corrisponding controls are implemented (see below), since
 177            they are adjusted in the core driver by calling the set_ctrl()
 178            method after init(), where the arguments are the default values
 179            specified in the v4l2_queryctrl list of supported controls;
 180            Same suggestions apply for other settings, _if_ the corresponding
 181            methods are present; if not, the initialization must configure the
 182            sensor according to the default configuration structures below.
 183         */
 184
 185         struct v4l2_queryctrl qctrl[SN9C102_MAX_CTRLS];
 186         /*
 187            Optional list of default controls, defined as indicated in the
 188            V4L2 API. Menu type controls are not handled by this interface.
 189         */
 190
 191         int (*get_ctrl)(struct sn9c102_device* cam, struct v4l2_control* ctrl);
 192         int (*set_ctrl)(struct sn9c102_device* cam,
 193                         const struct v4l2_control* ctrl);
 194         /*
 195            You must implement at least the set_ctrl method if you have defined
 196            the list above. The returned value must follow the V4L2
 197            specifications for the VIDIOC_G|C_CTRL ioctls. V4L2_CID_H|VCENTER
 198            are not supported by this driver, so do not implement them. Also,
 199            you don't have to check whether the passed values are out of bounds,
 200            given that this is done by the core module.
 201         */
 202
 203         struct v4l2_cropcap cropcap;
 204         /*
 205            Think the image sensor as a grid of R,G,B monochromatic pixels
 206            disposed according to a particular Bayer pattern, which describes
 207            the complete array of pixels, from (0,0) to (xmax, ymax). We will
 208            use this coordinate system from now on. It is assumed the sensor
 209            chip can be programmed to capture/transmit a subsection of that
 210            array of pixels: we will call this subsection "active window".
 211            It is not always true that the largest achievable active window can
 212            cover the whole array of pixels. The V4L2 API defines another
 213            area called "source rectangle", which, in turn, is a subrectangle of
 214            the active window. The SN9C1XX chip is always programmed to read the
 215            source rectangle.
 216            The bounds of both the active window and the source rectangle are
 217            specified in the cropcap substructures 'bounds' and 'defrect'.
 218            By default, the source rectangle should cover the largest possible
 219            area. Again, it is not always true that the largest source rectangle
 220            can cover the entire active window, although it is a rare case for
 221            the hardware we have. The bounds of the source rectangle _must_ be
 222            multiple of 16 and must use the same coordinate system as indicated
 223            before; their centers shall align initially.
 224            If necessary, the sensor chip must be initialized during init() to
 225            set the bounds of the active sensor window; however, by default, it
 226            usually covers the largest achievable area (maxwidth x maxheight)
 227            of pixels, so no particular initialization is needed, if you have
 228            defined the correct default bounds in the structures.
 229            See the V4L2 API for further details.
 230            NOTE: once you have defined the bounds of the active window
 231                  (struct cropcap.bounds) you must not change them.anymore.
 232            Only 'bounds' and 'defrect' fields are mandatory, other fields
 233            will be ignored.
 234         */
 235
 236         int (*set_crop)(struct sn9c102_device* cam,
 237                         const struct v4l2_rect* rect);
 238         /*
 239            To be called on VIDIOC_C_SETCROP. The core module always calls a
 240            default routine which configures the appropriate SN9C1XX regs (also
 241            scaling), but you may need to override/adjust specific stuff.
 242            'rect' contains width and height values that are multiple of 16: in
 243            case you override the default function, you always have to program
 244            the chip to match those values; on error return the corresponding
 245            error code without rolling back.
 246            NOTE: in case, you must program the SN9C1XX chip to get rid of
 247                  blank pixels or blank lines at the _start_ of each line or
 248                  frame after each HSYNC or VSYNC, so that the image starts with
 249                  real RGB data (see regs 0x12, 0x13) (having set H_SIZE and,
 250                  V_SIZE you don't have to care about blank pixels or blank
 251                  lines at the end of each line or frame).
 252         */
 253
 254         struct v4l2_pix_format pix_format;
 255         /*
 256            What you have to define here are: 1) initial 'width' and 'height' of
 257            the target rectangle 2) the initial 'pixelformat', which can be
 258            either V4L2_PIX_FMT_SN9C10X, V4L2_PIX_FMT_JPEG (for ompressed video)
 259            or V4L2_PIX_FMT_SBGGR8 3) 'priv', which we'll be used to indicate
 260            the number of bits per pixel for uncompressed video, 8 or 9 (despite
 261            the current value of 'pixelformat').
 262            NOTE 1: both 'width' and 'height' _must_ be either 1/1 or 1/2 or 1/4
 263                    of cropcap.defrect.width and cropcap.defrect.height. I
 264                    suggest 1/1.
 265            NOTE 2: The initial compression quality is defined by the first bit
 266                    of reg 0x17 during the initialization of the image sensor.
 267            NOTE 3: as said above, you have to program the SN9C1XX chip to get
 268                    rid of any blank pixels, so that the output of the sensor
 269                    matches the RGB bayer sequence (i.e. BGBGBG...GRGRGR).
 270         */
 271
 272         int (*set_pix_format)(struct sn9c102_device* cam,
 273                               const struct v4l2_pix_format* pix);
 274         /*
 275            To be called on VIDIOC_S_FMT, when switching from the SBGGR8 to
 276            SN9C10X pixel format or viceversa. On error return the corresponding
 277            error code without rolling back.
 278         */
 279
 280         /*
 281            Do NOT write to the data below, it's READ ONLY. It is used by the
 282            core module to store successfully updated values of the above
 283            settings, for rollbacks..etc..in case of errors during atomic I/O
 284         */
 285         struct v4l2_queryctrl _qctrl[SN9C102_MAX_CTRLS];
 286         struct v4l2_rect _rect;
 287 };
 288
 289 /*****************************************************************************/
 290
 291 /* Private ioctl's for control settings supported by some image sensors */
 292 #define SN9C102_V4L2_CID_DAC_MAGNITUDE (V4L2_CID_PRIVATE_BASE + 0)
 293 #define SN9C102_V4L2_CID_GREEN_BALANCE (V4L2_CID_PRIVATE_BASE + 1)
 294 #define SN9C102_V4L2_CID_RESET_LEVEL (V4L2_CID_PRIVATE_BASE + 2)
 295 #define SN9C102_V4L2_CID_PIXEL_BIAS_VOLTAGE (V4L2_CID_PRIVATE_BASE + 3)
 296 #define SN9C102_V4L2_CID_GAMMA (V4L2_CID_PRIVATE_BASE + 4)
 297 #define SN9C102_V4L2_CID_BAND_FILTER (V4L2_CID_PRIVATE_BASE + 5)
 298 #define SN9C102_V4L2_CID_BRIGHT_LEVEL (V4L2_CID_PRIVATE_BASE + 6)
 299
 300 #endif /* _SN9C102_SENSOR_H_ */