高通camera如何匹配I2C总线
1、dts配置
cci: qcom,cci@1b0c000 {
compatible = "qcom,cci";
...
pinctrl-names = "cci_default","cci_suspend";
pinctrl-0= <&cci0_default>;
pinctrl-1= <&cci0_sleep>;
gpios =<&msm_gpio 29 0>,//CAM_I2C_SCL
<&msm_gpio 30 0>;//CAM_I2C_SDA
...
};
2、kernel代码
代码：kernel/drivers/media/platform/msm/camera_v2/sensor/cci/msm_cci.c
static int msm_cci_probe(structplatform_device *pdev)
{
...
v4l2_subdev_init(&new_cci_dev->msm_sd.sd,&msm_cci_subdev_ops);//绑定操作集合
…
g_cci_subdev =&new_cci_dev->msm_sd.sd; //对外接口
...
}
static struct v4l2_subdev_core_opsmsm_cci_subdev_core_ops = {
.g_chip_ident =&msm_cci_subdev_g_chip_ident,
.ioctl = &msm_cci_subdev_ioctl,//控制接口函数
.interrupt_service_routine =msm_cci_irq_routine,
};
static const struct v4l2_subdev_opsmsm_cci_subdev_ops = {
.core = &msm_cci_subdev_core_ops,
};
static long msm_cci_subdev_ioctl(structv4l2_subdev *sd, unsigned int cmd, void *arg)
{
int32_t rc = 0;
CDBG("%s line %d\n",__func__, __LINE__);
switch (cmd) {
case VIDIOC_MSM_CCI_CFG:
rc = msm_cci_config(sd,arg);//具体的参数配置
break;
case MSM_SD_SHUTDOWN: {
struct msm_camera_cci_ctrlctrl_cmd;
ctrl_cmd.cmd = MSM_CCI_RELEASE;
rc = msm_cci_config(sd,&ctrl_cmd);
break;
}
default:
rc = -ENOIOCTLCMD;
}
CDBG("%s line %d rc %d\n",__func__, __LINE__, rc);
return rc;
}
static int32_t msm_cci_config(structv4l2_subdev *sd, struct msm_camera_cci_ctrl*cci_ctrl)
{
int32_t rc = 0;
CDBG("%s line %d cmd %d\n",__func__, __LINE__, cci_ctrl->cmd);
switch (cci_ctrl->cmd) {
case MSM_CCI_INIT:
rc =msm_cci_init(sd, cci_ctrl); //完成iic初始化
break;
case MSM_CCI_RELEASE:
rc = msm_cci_release(sd);
break;
case MSM_CCI_I2C_READ:
rc =msm_cci_i2c_read_bytes(sd, cci_ctrl); //iic读
break;
case MSM_CCI_I2C_WRITE:
rc =msm_cci_i2c_write(sd, cci_ctrl); //iic写
break;
case MSM_CCI_GPIO_WRITE:
break;
default:
rc = -ENOIOCTLCMD;
}
CDBG("%s line %d rc %d\n",__func__, __LINE__, rc);
cci_ctrl->status = rc;
return rc;
}
struct v4l2_subdev*msm_cci_get_subdev(void)
{
return g_cci_subdev;
}
注：kernel/drivers/media/platform/msm/camera_v2/sensor/cci/msm_cci.h中会声明struct v4l2_subdev*msm_cci_get_subdev(void);以提供对外接口，当camera相关模块probe时会通过此接口得到g_cci_subdev。