高通平台mm-camera上電時序
背景
作為高通平台Camera知識的一種補充。
參考文檔：https://blog.csdn.net/m0_37166404/article/details/64920910
介紹
高通平台對於camera的代碼組織，大體上還是遵循Android的框架，即：
- 上層應用和HAL層交互，高通平台在HAL層里面實現自己的一套管理策略；
- 在kernel中實現sensor的底層驅動；
- 對於最核心的sensor端的底層設置、ISP效果相關等代碼則是單獨進行了抽離，放在vendor中。
上電時序
時序屬性
路徑：vendor/qcom/proprietary/mm-camera/mm-camera2/media-controller/modules/sensors/includes/sensor_lib.h
- 最終位於：
kernel/include/media/msm_camsensor_sdk.h
struct msm_sensor_power_setting {
enum msm_sensor_power_seq_type_t seq_type;
uint16_t seq_val;
long config_val;
uint16_t delay;
void *data[10];
};
有關的時序設置
以：ov5648_q5v22e 為例。
對照規格書：
把DOVDD上電后，AVDD,DVDD,PWDNB的上電時序都大於圖中規定時間。
路徑：vendor/qcom/proprietary/mm-camera/mm-camera2/media-controller/modules/sensors/sensor_libs/xxx
例如：vendor/qcom/proprietary/mm-camera/mm-camera2/media-controller/modules/sensors/sensor_libs/ov5648_q5v22e當中的ov5648_q5v22e_lib.c
下面這個結構體便是上電時序
tatic struct msm_sensor_power_setting ov5648_q5v22e_power_setting[] = {
{
.seq_type = SENSOR_VREG,
.seq_val = CAM_VIO,
.config_val = 0,
.delay = 0,
},
{
.seq_type = SENSOR_VREG,
.seq_val = CAM_VANA,
.config_val = 0,
.delay = 0,
},
{
.seq_type = SENSOR_VREG,
.seq_val = CAM_VAF,
.config_val = 0,
.delay = 0,
},
{
.seq_type = SENSOR_GPIO,
.seq_val = SENSOR_GPIO_AF_PWDM,
.config_val = GPIO_OUT_LOW,
.delay = 1,
},
{
.seq_type = SENSOR_GPIO,
.seq_val = SENSOR_GPIO_AF_PWDM,
.config_val = GPIO_OUT_HIGH,
.delay = 5,
},
{
.seq_type = SENSOR_GPIO,
.seq_val = SENSOR_GPIO_RESET,
.config_val = GPIO_OUT_LOW,
.delay = 0,
},
{
.seq_type = SENSOR_GPIO,
.seq_val = SENSOR_GPIO_RESET,
.config_val = GPIO_OUT_HIGH,
.delay = 10,
},
{
.seq_type = SENSOR_GPIO,
.seq_val = SENSOR_GPIO_STANDBY,
.config_val = GPIO_OUT_LOW,
.delay = 0,
},
{
.seq_type = SENSOR_GPIO,
.seq_val = SENSOR_GPIO_STANDBY,
.config_val = GPIO_OUT_HIGH,
.delay = 5,
},
{
.seq_type = SENSOR_CLK,
.seq_val = SENSOR_CAM_MCLK,
.config_val = 24000000,
.delay = 10,
},
{
.seq_type = SENSOR_I2C_MUX,
.seq_val = 0,
.config_val = 0,
.delay = 0,
},
};
它會被下列的結構體中使用：
static struct msm_camera_sensor_slave_info sensor_slave_info = {
//...
/* power up / down setting */
.power_setting_array = {
.power_setting = ov5648_q5v22e_power_setting,
.size = ARRAY_SIZE(ov5648_q5v22e_power_setting),
.power_down_setting = power_down_setting,
.size_down = ARRAY_SIZE(power_down_setting),
},
};
這些Camera的屬性具體在msm_camsensor_sdk定義。
- 最終位於：
kernel/include/media/msm_camsensor_sdk.h
struct msm_camera_sensor_slave_info {
...
struct msm_sensor_power_setting_array power_setting_array;
...
};
struct msm_sensor_power_setting {
enum msm_sensor_power_seq_type_t seq_type;
uint16_t seq_val;
long config_val;
uint16_t delay;
void *data[10];
};
struct msm_sensor_power_setting_array {
struct msm_sensor_power_setting power_setting_a[MAX_POWER_CONFIG];
struct msm_sensor_power_setting *power_setting;
uint16_t size;
struct msm_sensor_power_setting power_down_setting_a[MAX_POWER_CONFIG];
struct msm_sensor_power_setting *power_down_setting;
uint16_t size_down;
};
驅動流程解析
在此之前是ioctl，注冊到v4l2子系統中。從vendor中把時序結構體的內容傳遞到kernel中的過程如下：
注意：vendor中的addr_type、camera_id、slave_addr等信息也是按照這樣的方法從vendor中傳遞到kernel中的，可以加打印調試信息看這些值正確與否。
++ kernel/drivers/media/platform/msm/camera_v2/sensor/msm_sensor_init.c
msm_sensor_init_subdev_ioctl()
msm_sensor_driver_cmd() : case VIDIOC_MSM_SENSOR_INIT_CFG
++ kernel/drivers/media/platform/msm/camera_v2/sensor/msm_sensor_driver.c
msm_sensor_driver_probe()
copy_from_user((void *)&setting32, setting,sizeof(setting32))
// 把 vendor 的時序傳遞完畢
slave_info->power_setting_array.size = setting32.power_setting_array.size;
slave_info->power_setting_array.power_setting =
compat_ptr(setting32.power_setting_array.power_setting);
// 把slave_info的上電時序傳遞給s_ctrl結構體
msm_sensor_get_power_settings
msm_sensor_get_power_up_settings(setting, slave_info, power_info);
/* 校正時序中SENSOR_VREG的seq_val，為設備樹的CAM_VIO */
msm_camera_fill_vreg_params();
/* 執行真正的上電程序*/
s_ctrl->func_tbl->sensor_power_up(s_ctrl);
(msm_sensor_power_up)
由於之前有 .sensor_power_up = msm_sensor_power_up,
所以最終為： msm_sensor_power_up
++ kernel/drivers/media/platform/msm/camera_v2/sensor/msm_sensor.c
//把s_ctrl的上電信息傳遞給power_info
power_info = &s_ctrl->sensordata->power_info;
sensor_i2c_client = s_ctrl->sensor_i2c_client;
slave_info = s_ctrl->sensordata->slave_info;
sensor_name = s_ctrl->sensordata->sensor_name;
// 通過之前設置好的時序上電
rc = msm_camera_power_up(power_info,
s_ctrl->sensor_device_type,
sensor_i2c_client);
msm_camera_power_up流程分析
解析這個上電函數：
int msm_camera_power_up(struct msm_camera_power_ctrl_t *ctrl,
enum msm_camera_device_type_t device_type,
struct msm_camera_i2c_client *sensor_i2c_client)
{
struct msm_sensor_power_setting *power_setting = NULL;
//...
rc = msm_camera_request_gpio_table( //申請gpio
ctrl->gpio_conf->cam_gpio_req_tbl,
ctrl->gpio_conf->cam_gpio_req_tbl_size, 1);
//...
index = 0; index < ctrl->power_setting_size; index++) {
//把時序的節點一個一個取下來解析
power_setting = &ctrl->power_setting[index];
//判斷類型
switch (power_setting->seq_type) {
case SENSOR_CLK:
if (power_setting->config_val)
ctrl->clk_info[power_setting->seq_val].clk_rate = power_setting->config_val;
//camera頻率使能
rc = msm_cam_clk_enable(...1);
//...
case SENSOR_GPIO:
//...
//拉高拉低gpio口
gpio_set_value_cansleep(ctrl->gpio_conf->gpio_num_info->gpio_num[power_setting->seq_val],
(int) power_setting->config_val);
//...
case SENSOR_VREG:
//函數里面打開reg_ptr的電源控制器regulator_enable，稍后會解析
if (power_setting->seq_val < ctrl->num_vreg)
msm_camera_config_single_vreg(...,1);
//...
case SENSOR_I2C_MUX:
if (ctrl->i2c_conf && ctrl->i2c_conf->use_i2c_mux)
msm_camera_enable_i2c_mux(ctrl->i2c_conf); //打開使能i2c_mux
break;
default:
//...
}
//以下是每個時序節點解析完畢后，進行的延遲，可以沒有
if (power_setting->delay > 20) {
msleep(power_setting->delay);
} else if (power_setting->delay) {
usleep_range(power_setting->delay * 1000,(power_setting->delay * 1000) + 1000);
}
}
//...
return 0;
}
兩個特殊節點
SENSOR_VREG
在解析設備樹節點的時候：
//從中有一路電vio為0V
qcom,cam-vreg-name = "cam_vdig", "cam_vio", "cam_vana";//"cam_vaf";
qcom,cam-vreg-min-voltage = <1800000 0 2850000 >;//2800000>;
qcom,cam-vreg-max-voltage = <1800000 0 2850000 >;//2800000>;
qcom,cam-vreg-op-mode = <200000 0 80000 100000>;
//在kernel中對設備樹節點解析的時候
for (i = 0; i < count; i++) {
vreg[i].min_voltage = vreg_array[i];}//存入結構體中
在msm_sensor_driver_probe函數中調用msm_camera_fill_vreg_params，在里面遍歷上電時序節點：
for (i = 0; i < power_setting_size; i++)
{
if (power_setting[i].seq_type != SENSOR_VREG)
continue;
switch (power_setting[i].seq_val) {
case CAM_VDIG:
//...
case CAM_VIO:
for (j = 0; j < num_vreg; j++) {
if (!strcmp(cam_vreg[j].reg_name, "cam_vio")) {
power_setting[i].seq_val = j; // 讓seq_val 對准設備樹的seq_val
break;
}
}
break;
//...
}
}
// 再進入此節點上電的時候有下列的語句，中間的參數就是設備樹上的電壓。
msm_camera_config_single_vreg(..&ctrl->cam_vreg[power_setting->seq_val],..);
SENSOR_I2C_MUX
執行函數msm_camera_enable_i2c_mux—>可能是申請鎖和一幀的內存空間
解析完畢后，最后兩個節點是打開時序和I2C_MUX，如果成功上電便完成了。