----------------------------------------------------------------------- | | |Aptina MT9D131 (2-meg pixel SOC) image sensor linux driver release | | | ----------------------------------------------------------------------- Release notes for the Aptina MT9D131 image sensor linux driver. This document contains information on how to download the OS, build the driver/OS and how to use the sensor. Please read this document before posting questions to the drivers@aptina.com e-mail address. MT9D131 Driver -------------- The MT9D131 driver is a Video for Linux 2 (V4L2) driver that is compiled into the Beagleboard-xM Linux Angstrom distribution. It is distributed under the GNU General Public License agreement which can be obtained from Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA02139, USA. TARGET HARDWARE/SOFTWARE ------------------------ - Beagleboard-xM Rev B. - Linux Angstrom Distribution, kernel release 2.6.32. - Aptina Beagleboard-XM Adapter/Revision 0 and MT9D131 2-megapixel soc sensor. DRIVER SOURCE CODE FILES ------------------------ Driver files and directory locations are listed below: mt9d131.c, Makefile, and Kconfig are located at: kernel-2.6.32/drivers/media/video mt9d131.h and v4l2-chip-ident.h are located at: kernel-2.6.32/include/media board-omap3beagle.c and board-omap3beagle-camera.c are located at: kernel-2.6.32/arch/arm/mach-omap2 BEAGLEBOARD/ANGSTROM SETUP -------------------------- For general beagleboard setup, please see the following link: http://code.google.com/p/beagleboard/wiki/HowToGetAngstromRunning Many of the Beagleboard/Angstrom files can be found at the following link: http://www.angstrom-distribution.org/demo/beagleboard/ The Linux kernel source code tar file beagleboard-validation-linux-beaglebardXM-camwork.tar.gz can be found at the following location: http://gitorious.org/beagleboard-validation/linux/trees/beaglebardXM-camwork Once downloaded, uncompress the file with the following command: $tar zxvf beagleboard-validation-linux-beaglebardXM-camwork.tar.gz Ignore the error messages if any. Download and install the compilation tool chain from: http://www.angstrom-distribution.org/toolchains/ For Intel i686 Linux desktop PC platforms, the tar toolchain file is: angstrom-2011.03-i686-linux-armv7a-linux-gnueabi-toolchain.tar.bz2 PREPARING SD-CARD ----------------- Download mkcard.sh from: http://gitorious.org/beagleboard-validation/scripts/trees/60f43aeb22e5ce799eda06c82e7d36d3f04cf7d2 Format & partition the sd-card at /dev/sdb (the actual drive mounts listed here may be different on your host system) $sudo $Beagleboard/binaries/mkcard.sh /dev/sdb This creates two partitions: /dev/sdb1 and /dev/sdb2, which are FAT32 and ext2 file formats respectively. LINUX KERNEL CONFIGURATION/COMPILATION -------------------------------------- Copy MT9D131 related files into the kernel directories: $cp your_mt9d131_driver_directory/board-omap3beagle.c ./arch/arm/mach-omap2 $cp your_mt9d131_driver_directory/board-omap3beagle-camera.c ./arch/arm/mach-omap2 $cp your_mt9d131_driver_directory/mt9d131.c ./drivers/media/video $cp your_mt9d131_driver_directory/Makefile ./drivers/media/video $cp your_mt9d131_driver_directory/Kconfig ./drivers/media/video $cp your_mt9d131_driver_directory/mt9d131.h ./include/media $cp your_mt9d131_driver_directory/v4l2-chip-ident.h ./include/media At the root directory of Linux kernel source files, enter the commands: $make ARCH=arm CROSS_COMPILE=arm-angstrom-linux-gnueabi- distclean $make ARCH=arm CROSS_COMPILE=arm-angstrom-linux-gnueabi- omap3_beagle_cam_defconfig $make ARCH=arm CROSS_COMPILE=arm-angstrom-linux-gnueabi- menuconfig In menuconfig, enable the MT9D131 driver. The Mt9D131 driver configuration is at the following location: "Device Drivers"-->"Multimedia support"-->"Video capture adapters"-->"Encoders/decoders and other helper chips" Select "mt9d131 support" as either <*> mt9d131 support so that the driver is part of kernel image, or mt9d131 support which configures the mt9d131 driver as a loadable module. Note: other image sensors (such as the MT9V011 or MT9P012) should be de-selected. Enable/Disable MT9D131 driver compilation options that are located in the mt9d131.c file: MT9D131_DEBUG - Define this to enable SYSFS sensor register access and debug printk support Undefine this for a driver release. Compile the kernel: $make ARCH=arm CROSS_COMPILE=arm-angstrom-linux-gnueabi- uImage and compile the mt9d131 driver separately if it is configured as a loadable module $make ARCH=arm CROSS_COMPILE=arm-angstrom-linux-gnueabi- modules Copy the kernel image to the SD card FAT partition: $cp arch/arm/boot/uImage /media/boot Copy the u-boot and x-loader images to the SD card FAT partition: $cp MLO /media/boot/ $cp u-boot.bin /media/boot/ Prebuilt versions of MLO and u-boot.bin can be downloaded from the following location: http://www.angstrom-distribution.org/demo/beagleboard/ Download the file-system file Angstrom-Beagleboard-demo-image-glibc-ipk-2011.1-beagleboard.rootfs.tar.bz2 from the following location: http://www.angstrom-distribution.org/demo/beagleboard/ Uncompress the file-system and copy it to the SD card EXT3 partition $sudo tar -C /media/Angstrom -xjvf Angstrom-Beagleboard-demo-image-glibc-ipk-2011.1-beagleboard.rootfs.tar.bz2 Copy the driver to the EXT3 partition if the mt9pd131 driver is configured as a loadable module $cp drivers/media/video/mt9d131.ko /media/Anstrom/home/root Then umount the card $sync; sudo umount /media/* Once the kernel and file-system are copied to the SD card, insert the SD card into the Beagleboard and power it on. BOOT UP BEAGLEBOARD ------------------- Follow the standard procedures to boot up the Beagleboard. If the sensor driver is configured as a loadable module, it needs to be inserted manually: #cd /home/root #insmod mt9d131.ko ANGSTROM VIDEO APPLICATION USING THE MT9D131 SENSOR --------------------------------------------------- The Angstrom "mplayer" video application can be used for previewing video at various resolutions such as VGA(640x480) or 720p(1280x720): $mplayer tv:// -tv driver=v4l2:width=640:height=480:device=/dev/video0:fps=12 -vo x11 $mplayer tv:// -tv driver=v4l2:width=1280:height=720:device=/dev/video0:fps=4 -vo x11 Note: run the following commands from the Angstrom terminal prompt if the mplayer application is not installed: #opkg install mplayer midori #opkg update; opkg install ntpdate MT9D131 SUPPORTED OUTPUT FRAME SIZES ------------------------------------ width=80, height=60 width=176, height=144 width=320, height=240 width=352, height=288 width=400, height=300 width=640, height=480 width=800, height=600 width=1280, height=720 width=1280, height=960 width=1280, height=1024 width=1600, height=1200 MT9D131 SUPPORTED OUTPUT FRAME FORMATS ------------------------------ YUYV(Y-Cb-Y-Cr) UYVY(Cb-Y-Cr-Y) USE MPLAYER TO TAKE SNAPSHOTS ----------------------------- To save a JPEG format image to the current directory: $mplayer tv:// -tv driver=v4l2:width=640:height=480:device=/dev/video0:fps=12 -vo jpeg $mplayer tv:// -tv driver=v4l2:width=1600:height=1200:device=/dev/video0:fps=4 -vo jpeg DIRECT ACCESS TO IMAGE SENSOR REGISTERS VIA SYSFS ------------------------------------------------- For the following to work, the MT9D131 driver must be compiled with the debugging option enabled (i.e., the MT9D131_DEBUG flag is enabled). The MT9D131 driver exposes device registers to the user via the SYSFS interface. This means device registers can be written/read as though they are files. To access sensor registers, navigate to the following system directory: $cd /sys/devices/platform/i2c_omap.2/i2c-2/2-0048/ Basic Register Read/Write for reading Register 0x07: $echo 0x07 > basic_reg_addr $cat basic_reg_val for writing 0x4 to Register 0x08: $echo 0x08 > basic_reg_addr $echo 0x04 > basic_reg_val KNOWN ISSUE ----------- V4L2 support is limited for this release: 1. The AE/AWB are on by default and cannot be disabled. 2. The maximum frame rate is 12 frame/seconds which changes dynamically depending on the lighting conditions and the frame size. The frame rate cannot be set to a specific value by end-user.