NVP6158简介
NVP6158C是一款4通道通用RX，提供高质量图像的芯片。它接受来自摄像机和其他视频信号的独立4通道通用输入来源。它将4通道通用1M至8M 7.5P视频格式数字化并解码为代表8位ITU-R BT.656/1120 4:2:2格式的数字分量视频，并将单独的BT.601格式与27/36/37.125MHz同步，54/72/74.25MHz和108/144/148.5/297MHz多路复用。54/72/74.25/108/144/148.5/297MHz复用功能可用，因为它在时钟范围内锁相环NVP6158C包括4通道模拟处理电路，包括抗混叠滤波器、ADC、钳位和均衡器滤波器。采用自适应高性能梳状滤波器和垂直峰值滤波器，获得了最佳的图像质量。它还支持可编程的饱和度、色调、亮度、对比度以及CTI、可编程峰值滤波器和各种补偿滤波器等多种功能。
RK DVP简介：
DVP（Digital Video Port） 是传统的sensor输出接口，采用并行输出方式，d数据位宽有8bit、10bit、12bit、16bit，是CMOS电平信号（重点是非差分信号），PCLK最大速率为96MHz，接口如下图：
PCLK：pixel clock ,像素时钟，每个时钟对应一个像素数据；
HSYNC：horizonal synchronization，行同步信号
VSYNC：vertical synchronization，帧同步信号；
DATA：像素数据，视频数据，具体位宽要看ISP是否支持；
XCLK：或者MCLK，ISP芯片输出给驱动sensor的时钟；
SCL，SDA：IIC用来读写sensor的寄存器，配置sensor。
NVP6158 与 RK3568 DVP连接相关原理图：
设备树配置：
&rkcif {
status = "okay";
memory-region = <&cif_reserved>;
};
&rkcif_dvp {
status = "okay";
ports {
#address-cells = <1>;
#size-cells = <0>;
port@0 {
#address-cells = <1>;
#size-cells = <0>;
/* Parallel bus endpoint */
dvp_in_bcam1: endpoint@1 {
reg = <1>;
remote-endpoint = <&nvp6158_out>;
bus-width = <16>;
};
};
};
};
nvp6158: nvp6158@30 {
compatible = "nvp6158-v4l2";
status = "okay";
reg = <0x30>;
clocks = <&cru CLK_CIF_OUT>;
clock-names = "xvclk";
power-domains = <&power RK3568_PD_VI>;
pinctrl-names = "default";
pinctrl-0 = <&cif_clk &cif_dvp_clk &cif_dvp_bus16>;
//pinctrl-0 = <&cif_dvp_clk &cif_dvp_bus8 &cif_dvp_bus16>;
pwr-gpios = <&gpio0 RK_PC4 GPIO_ACTIVE_HIGH>;
//pwr2-gpios = <&gpio4 RK_PC7 GPIO_ACTIVE_HIGH>;/* 360 camera */
rst-gpios = <&gpio4 RK_PA6 GPIO_ACTIVE_HIGH>;
/*rst2-gpios = <&gpio2 RK_PC5 GPIO_ACTIVE_HIGH>;*/
/*pwdn-gpios = <&gpio4 RK_PA6 GPIO_ACTIVE_HIGH>;*/
/*pwdn2-gpios = <&gpio4 RK_PA6 GPIO_ACTIVE_HIGH>;*/
rockchip,camera-module-index = <0>;
rockchip,camera-module-facing = "back";
rockchip,camera-module-name = "default";
rockchip,camera-module-lens-name = "default";
rockchip,dvp_mode = "BT1120"; //BT656 or BT1120 or BT656_TEST
rockchip,channel_nums = <4>; //channel nums, 1/2/4
rockchip,dual_edge = <0>; // pclk dual edge, 0/1
rockchip,default_rect= <1920 1080>; // default resolution
port {
nvp6158_out: endpoint {
remote-endpoint = <&dvp_in_bcam1>;
};
};
};clocks = <&cru CLK_CIF_OUT>; //走GPIO CIF时钟 配置为是27M
clock-names = "xvclk";
nvp6158->xvclk = devm_clk_get(dev, "xvclk");
if (IS_ERR(nvp6158->xvclk)) {
dev_err(dev, "Failed to get xvclk\n");
return -EINVAL;
}
if (ret < 0) {
#define NVP6158_XVCLK_FREQ 27000000
ret = clk_set_rate(nvp6158->xvclk, NVP6158_XVCLK_FREQ);
dev_err(dev, "Failed to set xvclk rate (24MHz)\n");
return ret;
}rockchip,dvp_mode = "BT1120" ：走BT1120模式
rockchip,channel_nums = <4>;//并口的数据lane ，只有一条lane 可配置1 参数：1/2/4
rockchip,default_rect= <1280 720>;摄像头分辨率。 rkcif会从nvp6158驱动里获取
rockchip,dual_edge ：pclk的边沿有效 一般用于配置分辨率 720p：0 1080P：1 如下
rkcif 会获取对应的pclk dual_edge
static int nvp6158_g_mbus_config(struct v4l2_subdev *sd,
struct v4l2_mbus_config *cfg)
{
struct nvp6158 *nvp6158 = to_nvp6158(sd);
cfg->type = V4L2_MBUS_BT656;
if (nvp6158->dual_edge == 1) {
cfg->flags = RKMODULE_CAMERA_BT656_CHANNELS |
V4L2_MBUS_PCLK_SAMPLE_RISING |
V4L2_MBUS_PCLK_SAMPLE_FALLING;
} else {
cfg->flags = RKMODULE_CAMERA_BT656_CHANNELS |
V4L2_MBUS_PCLK_SAMPLE_RISING;
}
return 0;
}nvp6158关注的代码：
初始化热拔插工作队列：
INIT_DELAYED_WORK(&nvp6158->plug_state_check.d_work, nvp6158_plug_state_check_work);
nvp6158->plug_state_check.state_check_wq =
create_singlethread_workqueue("nvp6158_work_queue");
if (nvp6158->plug_state_check.state_check_wq == NULL) {
dev_err(dev, "%s(%d): %s create failed.\n", __func__, __LINE__,
"nvp6158_work_queue");
}热拔插队列：打开DVP摄像头后 nvp6158_no_signal 读取nvp6158 0xa8地址，判断摄像头有无接入
#ifdef WORK_QUEUE
static void nvp6158_plug_state_check_work(struct work_struct *work)
{
struct sensor_state_check_work *params_check =
container_of(work, struct sensor_state_check_work, d_work.work);
struct nvp6158 *nvp6158 =
container_of(params_check, struct nvp6158, plug_state_check);
struct i2c_client *client = nvp6158->client;
struct v4l2_subdev *sd = &nvp6158->subdev;
u8 novid_status = 0x00;
u8 sync_status = 0x00;
nvp6158_no_signal(sd, &novid_status);
nvp6158_sync(sd, &sync_status);
nvp6158->cur_detect_status = novid_status;
/* detect state change to determine is there has plug motion */
novid_status = nvp6158->cur_detect_status ^ nvp6158->last_detect_status;
if (novid_status)
nvp6158->hot_plug = true;
else
nvp6158->hot_plug = false;
nvp6158->last_detect_status = nvp6158->cur_detect_status;
dev_info(&client->dev, "%s has plug motion? (%s)", __func__,
nvp6158->hot_plug ? "true" : "false");
if (nvp6158->hot_plug) {
dev_info(&client->dev, "queue_delayed_work 1500ms, if has hot plug motion.");
queue_delayed_work(nvp6158->plug_state_check.state_check_wq,
&nvp6158->plug_state_check.d_work, msecs_to_jiffies(1500));
nvp6158_write(client, 0xFF, 0x20);
nvp6158_write(client, 0x00, (sync_status << 4) | sync_status);
usleep_range(3000, 5000);
nvp6158_write(client, 0x00, 0xFF);
} else {
dev_info(&client->dev, "queue_delayed_work 100ms, if no hot plug motion.");
queue_delayed_work(nvp6158->plug_state_check.state_check_wq,
&nvp6158->plug_state_check.d_work, msecs_to_jiffies(100));
}
}
#endif调试：
I2C无法读取写入：
1.确认电源电压
2.确认时钟脚有无27M CLK信号
3.排查是否其他器件影响
无图像：1.确认时钟脚有无27M CLK信号
2.确认下发的分辨率与接入的摄像头是否对应得上
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