ov7660.c

   1 /**
   2  * @file ov7660.c
   3  * @author Neekhil
   4  * @date 2008-08-24
   5  *
   6  * @brief Common control functions for the Omnivision OV7660 series Image Sensors.
   7  *
   8  * @note Copyright (C) Neekhil
   9  *
  10  * @par Licences
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  25  */
  26
  27 #include "microdia.h"
  28 #include "sn9c20x.h"
  29 #include "ov7660.h"
  30
  31 int ov7660_sleep(struct usb_microdia *dev);
  32 int ov7660_wakeup(struct usb_microdia *dev);
  33 int ov7660_reset(struct usb_microdia *dev);
  34
  35 static __u8 ov7660_init[][2] = {
  36         /* System CLK selection, to get a higher Frame Rate */
  37         {OV7660_CTL_COM5, 0x80},
  38         /* OV7660 Wakeup */
  39         /* COM4 is Reserved : using default value 0x40 OR windows driver value 0x08 */
  40         {OV7660_CTL_COM4, 0x08},
  41         /* Enable HREF at optical black, Use optical black line as BLC signal
  42             Reset all timing when format changes, Enable ADBLC option */
  43         {OV7660_CTL_COM6, 0xc3},
  44         /* windows 0x00, default 0x00, trying 0x60 to enable CCIR656 format */
  45         {OV7660_CTL_COM1, 0xc3},
  46         /* default is 0x40, windows sets it to 0x00 */
  47         {OV7660_CTL_AECH, 0x40},
  48         /* default is 0x00, windows sets it to 0x40 */
  49         {OV7660_CTL_CLKRC, 0x40},
  50         /* Set O/P format - RGB Selection, Set O/P format Raw RGB */
  51         {OV7660_CTL_COM7, 0x05},
  52         /* default is 0x8f, windows used 0xf8 */
  53         /* Enable fast AGC/AEC algorithm, AEC - Step size limit = 1/16 x AEC */
  54         /* Banding & Reserved are disabled. AGC, AEC enabled, 0x85 */
  55         {OV7660_CTL_COM8, 0xb8},
  56         /* video appears jagged w/o these  ADC writes */
  57         {OV7660_CTL_ADC, 0x0f},
  58         {OV7660_CTL_ACOM, 0x02},
  59         {OV7660_CTL_OFON, 0x43},
  60         /* video appears jagged w/o this write */
  61         /* Default 0x0c sets format to uYvY, Windows driver 0x00 sets format to YuYv */
  62         {OV7660_CTL_TSLB, 0x00},
  63         /* Not doing this write makes the video look green */
  64         /* Manual Banding Filter MSB , set B & R channel pre-gain */
  65         {OV7660_CTL_HV, 0x90},
  66         /*  No video stream w/o these ADVFL/ADVFH write totally black */
  67         {OV7660_CTL_ADVFL, 0xf6},
  68         {OV7660_CTL_ADVFH, 0x0b},
  69         /* Setting BLUE to 0x78; RED to 0x78 to get natural colors in artificial light */
  70         {OV7660_CTL_BLUE, 0x78},
  71         /* Setting RED to 0x50 to get natural colors in natural light */
  72         {OV7660_CTL_RED,  0x50},
  73 };
  74
  75 int ov7660_initialize(struct usb_microdia *dev)
  76 {
  77         int ret, i;
  78         __u8 value, reg;
  79
  80         ret = sn9c20x_i2c_initialize(dev);
  81         ret = ov7660_reset(dev);
  82
  83         ret = ov7660_wakeup(dev);
  84
  85         for (i = 0; i < ARRAY_SIZE(ov7660_init); i++) {
  86                 reg = ov7660_init[i][0];
  87                 value = ov7660_init[i][1];
  88                 ret = sn9c20x_write_i2c_data(dev, dev->sensor_slave_address, 1,
  89                                              reg, dev->sensor_flags, &value);
  90                 if (ret < 0) {
  91                         UDIA_INFO("Sensor OV7660: Inititialization Error (%d) on array line %d\n", ret, i);
  92                         break;
  93                 }
  94         }
  95
  96         return ret;
  97 }
  98
  99 /**
 100  * @brief Set exposure for ov7660 sensors
 101  *
 102  * @param dev
 103  *
 104  * @return 0 or negative error value
 105  *
 106  * @author Neekhil
 107 */
 108 int ov7660_set_exposure(struct usb_microdia *dev)
 109 {
 110         int ret = 0;
 111         __u8 v1 = (dev->vsettings.exposure >> 4) & 0xff;
 112         __u8 v2 = dev->vsettings.exposure >> 12;
 113
 114         ret |= sn9c20x_write_i2c_data(dev, dev->sensor_slave_address, 1, OV7660_CTL_ADVFL,
 115                 dev->sensor_flags, &v1);
 116
 117         ret |= sn9c20x_write_i2c_data(dev, dev->sensor_slave_address, 1, OV7660_CTL_ADVFH,
 118                 dev->sensor_flags, &v2);
 119
 120         return ret;
 121 }
 122
 123 /**
 124  * @brief Set autoexposure for ov7660 sensors
 125  *
 126  * @param dev
 127  *
 128  * @return 0 or negative error value
 129  *
 130  * @author Neekhil
 131 */
 132 int ov7660_set_autoexposure(struct usb_microdia *dev)
 133 {
 134         __u8 buf[1];
 135         int ret = 0;
 136
 137         /* Read current value of the I2C-register
 138          * controlling AutoExposureControl:
 139          */
 140         ret = sn9c20x_read_i2c_data(dev, dev->sensor_slave_address,
 141                 1, OV7660_CTL_COM8, dev->sensor_flags, buf);
 142         if (ret < 0) {
 143                 UDIA_ERROR("Error: setting of auto exposure failed: "
 144                         "error while reading from I2C-register OV7660_CTL_COM8");
 145                 return ret;
 146         }
 147
 148         /* Determine new value for OV7660_CTL_COM8 register */
 149         if (dev->vsettings.auto_exposure == 1) {
 150                 /* Enable automatic exposure: */
 151                 buf[0] |= 0x01;
 152         } else if (dev->vsettings.auto_exposure == 0) {
 153                 /* Disable automatic exposure: */
 154                 buf[0] &= ~0x01;
 155         } else
 156                 return -EINVAL;
 157
 158         /* Write new value to I2C-register OV7660_CTL_COM8 */
 159         ret = sn9c20x_write_i2c_data(dev, dev->sensor_slave_address,
 160                 1, OV7660_CTL_COM8, dev->sensor_flags, buf);
 161         if (ret < 0) {
 162                 UDIA_ERROR("Error: setting of auto exposure failed: "
 163                         "error while writing to I2C-register OV7660_CTL_COM8");
 164                 return ret;
 165         }
 166         return 0;
 167 }
 168
 169 /**
 170  * @brief Set ov7660 sensors to soft-sleep mode
 171  * @param dev
 172  * @return 0 or negative error value
 173  * @author Neekhil
 174 */
 175 int ov7660_sleep(struct usb_microdia *dev)
 176 {
 177         __u8 buf[1];
 178         int ret = 0;
 179
 180         /* Set the sensor to Soft Sleep mode, Set O/P drive capability to 4X*/
 181         buf[0] = 0x13;
 182         ret = sn9c20x_write_i2c_data(dev, dev->sensor_slave_address, 1,
 183                                         OV7660_CTL_COM2, dev->sensor_flags, buf);
 184         if (ret < 0)
 185                 goto errI2C;
 186
 187         return 0;
 188
 189 errI2C:
 190         UDIA_ERROR("Setting Image Sensor to soft sleep  failed(%d)!\n", ret);
 191         return ret;
 192 }
 193
 194 /**
 195  * @brief Get ov7660 sensors to wake up from soft-sleep mode
 196  * @param dev
 197  * @return 0 or negative error value
 198  * @author Neekhil
 199 */
 200 int ov7660_wakeup(struct usb_microdia *dev)
 201 {
 202         __u8 buf[1];
 203         int ret = 0;
 204
 205         /* Wake the sensor from Soft Sleep mode, Set O/P drive capability to 4X */
 206         buf[0] = 0x03;
 207         ret = sn9c20x_write_i2c_data(dev, dev->sensor_slave_address, 1,
 208                                         OV7660_CTL_COM2, dev->sensor_flags, buf);
 209         if (ret < 0)
 210                 goto errI2C;
 211
 212         return 0;
 213
 214 errI2C:
 215         UDIA_ERROR("Image Sensor failed to wake-up from soft sleep (%d)!\n", ret);
 216         return ret;
 217 }
 218
 219 /**
 220  * @brief Resets all the registers on ov7660 sensor
 221  * @param dev
 222  * @return 0 or negative error value
 223  * @author Neekhil
 224 */
 225 int ov7660_reset(struct usb_microdia *dev)
 226 {
 227         __u8 buf[1];
 228         int ret = 0;
 229
 230         /* Reset all registers to default value                                    */
 231         /* Set O/P format - RGB Selection, Set O/P format Raw RGB */
 232         buf[0] = 0x85;
 233         ret = sn9c20x_write_i2c_data(dev, dev->sensor_slave_address, 1,
 234                                         OV7660_CTL_COM7, dev->sensor_flags, buf);
 235         if (ret < 0)
 236                 goto errI2C;
 237
 238         return 0;
 239
 240 errI2C:
 241         UDIA_ERROR("Failed to reset the Image Sensor (%d)!\n", ret);
 242         return ret;
 243 }