ov7660.c

   1 /**
   2  * @file ov7660.c
   3  * @author Neekhil
   4  * @date 2008-08-24
   5  * @version v0.0.0
   6  *
   7  * @brief Common control functions for the Omnivision OV7660 series Image Sensors.
   8  *
   9  * @note Copyright (C) Neekhil
  10  *
  11  * @par Licences
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  26  */
  27
  28 #include "microdia.h"
  29 #include "sn9c20x.h"
  30 #include "ov7660.h"
  31
  32 int ov7660_sleep(struct usb_microdia *dev);
  33 int ov7660_wakeup(struct usb_microdia *dev);
  34 int ov7660_reset(struct usb_microdia *dev);
  35
  36 static __u8 ov7660_init[][2] = {
  37         /* System CLK selection, to get a higher Frame Rate */
  38         {OV7660_CTL_COM5, 0x80},
  39         /* OV7660 Wakeup */
  40         /* COM4 is Reserved : using default value 0x40 OR windows driver value 0x08 */
  41         {OV7660_CTL_COM4, 0x08},
  42         /* Enable HREF at optical black, Use optical black line as BLC signal
  43             Reset all timing when format changes, Enable ADBLC option */
  44         {OV7660_CTL_COM6, 0xc3},
  45         /* windows 0x00, default 0x00, trying 0x60 to enable CCIR656 format */
  46         {OV7660_CTL_COM1, 0xc3},
  47         /* default is 0x40, windows sets it to 0x00 */
  48         {OV7660_CTL_AECH, 0x40},
  49         /* default is 0x00, windows sets it to 0x40 */
  50         {OV7660_CTL_CLKRC, 0x40},
  51         /* Set O/P format - RGB Selection, Set O/P format Raw RGB */
  52         {OV7660_CTL_COM7, 0x05},
  53         /* default is 0x8f, windows used 0xf8 */
  54         /* Enable fast AGC/AEC algorithm, AEC - Step size limit = 1/16 x AEC */
  55         /* Banding & Reserved are disabled. AGC, AEC enabled, 0x85 */
  56         {OV7660_CTL_COM8, 0xb8},
  57         /* video appears jagged w/o these  ADC writes */
  58         {OV7660_CTL_ADC, 0x0f},
  59         {OV7660_CTL_ACOM, 0x02},
  60         {OV7660_CTL_OFON, 0x43},
  61         /* video appears jagged w/o this write */
  62         /* Default 0x0c sets format to uYvY, Windows driver 0x00 sets format to YuYv */
  63         {OV7660_CTL_TSLB, 0x00},
  64         /* Not doing this write makes the video look green */
  65         /* Manual Banding Filter MSB , set B & R channel pre-gain */
  66         {OV7660_CTL_HV, 0x90},
  67         /*  No video stream w/o these ADVFL/ADVFH write totally black */
  68         {OV7660_CTL_ADVFL, 0xf6},
  69         {OV7660_CTL_ADVFH, 0x0b},
  70         /* Setting BLUE to 0x78; RED to 0x78 to get natural colors in artificial light */
  71         {OV7660_CTL_BLUE, 0x78},
  72         /* Setting RED to 0x50 to get natural colors in natural light */
  73         {OV7660_CTL_RED,  0x50},
  74 };
  75
  76 int ov7660_initialize(struct usb_microdia *dev)
  77 {
  78         int ret, i;
  79         __u8 value, reg;
  80
  81         ret = sn9c20x_i2c_initialize(dev);
  82         ret = ov7660_reset(dev);
  83
  84         ret = ov7660_wakeup(dev);
  85
  86         for (i = 0; i < ARRAY_SIZE(ov7660_init); i++) {
  87                 reg = ov7660_init[i][0];
  88                 value = ov7660_init[i][1];
  89                 ret = sn9c20x_write_i2c_data(dev, dev->sensor_slave_address, 1,
  90                                              reg, dev->sensor_flags, &value);
  91                 if (ret < 0) {
  92                         UDIA_INFO("Sensor OV7660: Inititialization Error (%d) on array line %d", ret, i);
  93                         break;
  94                 }
  95         }
  96
  97         return ret;
  98 }
  99
 100 /**
 101  * @brief Set exposure for ov7660 sensors
 102  *
 103  * @param dev
 104  *
 105  * @return 0 or negative error value
 106  *
 107  * @author Neekhil
 108 */
 109 int ov7660_set_exposure(struct usb_microdia *dev)
 110 {
 111         int ret = 0;
 112         __u8 v1 = (dev->vsettings.exposure >> 4) & 0xff;
 113         __u8 v2 = dev->vsettings.exposure >> 12;
 114
 115         ret |= sn9c20x_write_i2c_data(dev, dev->sensor_slave_address, 1, OV7660_CTL_ADVFL,
 116                 dev->sensor_flags, &v1);
 117
 118         ret |= sn9c20x_write_i2c_data(dev, dev->sensor_slave_address, 1, OV7660_CTL_ADVFH,
 119                 dev->sensor_flags, &v2);
 120
 121         return ret;
 122 }
 123
 124 /**
 125  * @brief Set autoexposure for ov7660 sensors
 126  *
 127  * @param dev
 128  *
 129  * @return 0 or negative error value
 130  *
 131  * @author Neekhil
 132 */
 133 int ov7660_set_autoexposure(struct usb_microdia *dev)
 134 {
 135         __u8 buf[1];
 136         int ret = 0;
 137
 138         /* Read current value of the I2C-register
 139          * controlling AutoExposureControl:
 140          */
 141         ret = sn9c20x_read_i2c_data(dev, dev->sensor_slave_address,
 142                 1, OV7660_CTL_COM8, dev->sensor_flags, buf);
 143         if (ret < 0) {
 144                 UDIA_ERROR("Error: setting of auto exposure failed: "
 145                         "error while reading from I2C-register OV7660_CTL_COM8");
 146                 return ret;
 147         }
 148
 149         /* Determine new value for OV7660_CTL_COM8 register */
 150         if (dev->vsettings.auto_exposure == 1) {
 151                 /* Enable automatic exposure: */
 152                 buf[0] |= 0x01;
 153         } else if (dev->vsettings.auto_exposure == 0) {
 154                 /* Disable automatic exposure: */
 155                 buf[0] &= ~0x01;
 156         } else
 157                 return -EINVAL;
 158
 159         /* Write new value to I2C-register OV7660_CTL_COM8 */
 160         ret = sn9c20x_write_i2c_data(dev, dev->sensor_slave_address,
 161                 1, OV7660_CTL_COM8, dev->sensor_flags, buf);
 162         if (ret < 0) {
 163                 UDIA_ERROR("Error: setting of auto exposure failed: "
 164                         "error while writing to I2C-register OV7660_CTL_COM8");
 165                 return ret;
 166         }
 167         return 0;
 168 }
 169
 170 /**
 171  * @brief Set ov7660 sensors to soft-sleep mode
 172  * @param dev
 173  * @return 0 or negative error value
 174  * @author Neekhil
 175 */
 176 int ov7660_sleep(struct usb_microdia *dev)
 177 {
 178         __u8 buf[1];
 179         int ret = 0;
 180
 181         /* Set the sensor to Soft Sleep mode, Set O/P drive capability to 4X*/
 182         buf[0] = 0x13;
 183         ret = sn9c20x_write_i2c_data(dev, dev->sensor_slave_address, 1,
 184                                         OV7660_CTL_COM2, dev->sensor_flags, buf);
 185         if (ret < 0)
 186                 goto errI2C;
 187
 188         return 0;
 189
 190 errI2C:
 191         UDIA_ERROR("Setting Image Sensor to soft sleep  failed(%d)!\n", ret);
 192         return ret;
 193 }
 194
 195 /**
 196  * @brief Get ov7660 sensors to wake up from soft-sleep mode
 197  * @param dev
 198  * @return 0 or negative error value
 199  * @author Neekhil
 200 */
 201 int ov7660_wakeup(struct usb_microdia *dev)
 202 {
 203         __u8 buf[1];
 204         int ret = 0;
 205
 206         /* Wake the sensor from Soft Sleep mode, Set O/P drive capability to 4X */
 207         buf[0] = 0x03;
 208         ret = sn9c20x_write_i2c_data(dev, dev->sensor_slave_address, 1,
 209                                         OV7660_CTL_COM2, dev->sensor_flags, buf);
 210         if (ret < 0)
 211                 goto errI2C;
 212
 213         return 0;
 214
 215 errI2C:
 216         UDIA_ERROR("Image Sensor failed to wake-up from soft sleep (%d)!\n", ret);
 217         return ret;
 218 }
 219
 220 /**
 221  * @brief Resets all the registers on ov7660 sensor
 222  * @param dev
 223  * @return 0 or negative error value
 224  * @author Neekhil
 225 */
 226 int ov7660_reset(struct usb_microdia *dev)
 227 {
 228         __u8 buf[1];
 229         int ret = 0;
 230
 231         /* Reset all registers to default value                                    */
 232         /* Set O/P format - RGB Selection, Set O/P format Raw RGB */
 233         buf[0] = 0x85;
 234         ret = sn9c20x_write_i2c_data(dev, dev->sensor_slave_address, 1,
 235                                         OV7660_CTL_COM7, dev->sensor_flags, buf);
 236         if (ret < 0)
 237                 goto errI2C;
 238
 239         return 0;
 240
 241 errI2C:
 242         UDIA_ERROR("Failed to reset the Image Sensor (%d)!\n", ret);
 243         return ret;
 244 }