Camera 使用

前言

FirePrime 开发板上有 CIF 接口,支持 CIF 双摄像头。 在 kernel/drivers/media/video 目录里有以下 CIF 摄像头的驱动:

  • gc0307
  • gc0308
  • gc0309
  • gc0328
  • gc0329
  • gc2015
  • gc2035
  • gt2005
  • hm2057
  • hm5065
  • mt9p111
  • nt99160
  • nt99240
  • ov2659
  • ov5640
  • sp0838
  • sp2518

本章主要描述如何配置 CIF。

配置步骤

加入传感器的连接信息

在 kernel/arch/arm/boot/dts/rk3128-cif-sensor.dtsi 定义摄像头列表:

rk3128_cif_sensor: rk3128_cif_sensor{
        compatible = "rockchip,sensor";
        status = "disabled";
        CONFIG_SENSOR_POWER_IOCTL_USR 		= <1>;
        CONFIG_SENSOR_RESET_IOCTL_USR 		= <0>;
        CONFIG_SENSOR_POWERDOWN_IOCTL_USR	= <0>;
        CONFIG_SENSOR_FLASH_IOCTL_USR	  	= <0>;
        CONFIG_SENSOR_AF_IOCTL_USR	   		= <0>;
// ... skip some modules
gc0329{
			is_front = <1>;
			rockchip,powerdown = <&gpio3 GPIO_D7 GPIO_ACTIVE_HIGH>;
			pwdn_active = <gc0329_PWRDN_ACTIVE>;
			#rockchip,power = <>;
			pwr_active = <PWR_ACTIVE_HIGH>;
			#rockchip,reset = <>;
			#rst_active = <>;
			#rockchip,flash = <>;
			#rockchip,af = <>;
			mir = <0>;
			flash_attach = <0>;
			resolution = <gc0329_FULL_RESOLUTION>;
			powerup_sequence = <gc0329_PWRSEQ>;
			orientation = <0>;
			i2c_add = <gc0329_I2C_ADDR>;
			i2c_rata = <100000>;
			i2c_chl = <0>;
			cif_chl = <0>;
			mclk_rate = <24>;
		};
    gc0329_b {
        is_front = <0>;
        rockchip,powerdown = <&gpio3 GPIO_B3 GPIO_ACTIVE_HIGH>;
        pwdn_active = <gc0329_PWRDN_ACTIVE>;
        #rockchip,power = <>;
        pwr_active = <PWR_ACTIVE_HIGH>;
        #rockchip,reset = <>;
        #rst_active = <>;
        #rockchip,flash = <>;
        #rockchip,af = <>;
        mir = <0>;
        flash_attach = <0>;
        resolution = <gc0329_FULL_RESOLUTION>;
        powerup_sequence = <gc0329_PWRSEQ>;
        orientation = <0>;
        i2c_add = <gc0329_I2C_ADDR>;
        i2c_rata = <100000>;
        i2c_chl = <0>; // <0>;
        cif_chl = <0>;
        mclk_rate = <24>;
		};
	};

这里列出 gc0329 双摄像头模组的配置,其属性解释如下:

  • is_front: 0: 后置摄像头,1: 前置摄像头
  • rockchip,powerdown: 定义该摄像头对应的 powerdown gpio
  • pwdn_active: powerdown 的有效电平
  • mir: 0: 不支持镜像,1: 支持镜像,
  • resolution: 最大的分辨率
  • orientation: 旋转角度,0: 0 度, 90: 90 度, 180: 180 度, 270: 270 度
  • i2c_add: 摄像头的 I2C 地址
  • i2c_rata: I2C 频率,单位 Hz
  • i2c_chl: I2C 通道号
  • cif_chl: cif 控制器信息,rk312x 仅有 cif0
  • mclk_rate: 传感器时钟频率,单位:MHz

其中的常量值都在 kernel/arch/arm/mach-rockchip/rk_camera_sensor_info.h 中定义:

#define gc0329_FULL_RESOLUTION      0x30000            // 0.3 megapixel
#define gc0329_I2C_ADDR             0x62
#define gc0329_PWRDN_ACTIVE             0x01
#define gc0329_PWRSEQ                   sensor_PWRSEQ_DEFAULT
//Sensor power  active level define
#define PWR_ACTIVE_HIGH                  0x01
#define PWR_ACTIVE_LOW					 0x0

分辨率对应的图像长宽,在 kernel/drivers/media/video/generic_sensor.h 的 sensor_get_full_width_height 函数里定义:

static inline int sensor_get_full_width_height(int full_resolution, unsigned short *w, unsigned short *h)
{
    switch (full_resolution)
    {
        case 0x30000:
        {
            *w = 640;
            *h = 480;
            break;
        }
 
        case 0x100000:
        {
            *w = 1024;
            *h = 768;
            break;
        }
        //...
    }
}

启用 CIF 传感器设备

要启用 CIF ,只需在 kernel/arch/arm/boot/dts/rk3128-fireprime.dts 加入:

&rk3128_cif_sensor{
    status = "okay";
};