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3. 模块图

4. 引脚

5. 参考电路

6. i2c时序

由以下时序可以看到，vcm9714利用I2C接口通信时，每次读/写，直接传输2个字节的数据，通信之前，不需要发送内部寄存器地址。

(资料图片)

7. 寄存器格式

三、驱动移植

vcm9714与rk3568连接图：

@arch/arm64/boot/dts/rockchip/rk3568-evb1-ddr4-v10.dtsi560dw9714:dw9714@c{561compatible="dongwoon,dw9714";562status="okay";563reg=<0x0c>;564rockchip,camera-module-index=<0>;565rockchip,vcm-start-current=<10>;566rockchip,vcm-rated-current=<85>;567rockchip,vcm-step-mode=<5>;568rockchip,camera-module-facing="back";569};570571ov13850:ov13850@10{……584lens-focus=<&dw9714>;……591};

其中，下面这两个属性，必须要和对应的的摄像头ov13850信息保持一致

rockchip,camera-module-index=<0>;rockchip,camera-module-facing="back";

摄像头支持的马达驱动信息通过以下属性关联

lens-focus=<&dw9714>;

@kernel\drivers\media\i2c\Makefileobj-$(CONFIG_VIDEO_DW9714)+=dw9714.o

@kernel\drivers\media\i2c\KconfigconfigVIDEO_DW9714tristate"DW9714lensvoicecoilsupport"dependsonI2C&&VIDEO_V4L2&&MEDIA_CONTROLLERdependsonVIDEO_V4L2_SUBDEV_API---help---ThisisadriverfortheDW9714cameralensvoicecoil.DW9714isa10bitDACwith120mAoutputcurrentsinkcapability.Thisisdesignedforlinearcontrolofvoicecoilmotors,controlledviaI2Cserialinterface.

@arch/arm64/configs/rockchip_defconfig572CONFIG_VIDEO_DW9714=y

rk_android11.0_sdk_220718\kernel\drivers\media\i2c\dw9714.c

四、调试信息

1. 启动的驱动log

[0.800799]vm149c4-000c:probing...[0.800820]vm149c4-000c:driverversion:00.01.00[0.800834]vm149c4-000c:couldnotgetmodulerockchip,vcm-max-currentfromdts![0.800847]vm149c4-000c:couldnotgetmodulerockchip,vcm-start-currentfromdts![0.800860]vm149c4-000c:couldnotgetmodulerockchip,vcm-rated-currentfromdts![0.800872]vm149c4-000c:couldnotgetmodulerockchip,vcm-step-modefromdts![0.800907]vm149c4-000c:probingsuccessful

2. 查看拓扑结构

media-ctl-p……………-entity74:m00_b_ov138504-0010(1pad,1link)typeV4L2subdevsubtypeSensordevicenodename/dev/v4l-subdev4pad0:Source[fmt:SBGGR10/4224x3136]->"rockchip-csi2-dphy0":0[]-entity78:m00_b_gpio-flash(0pad,0link)typeV4L2subdevsubtypeFlashdevicenodename/dev/v4l-subdev5-entity79:m00_b_dw97144-000c(0pad,0link)typeV4L2subdevsubtypeLensdevicenodename/dev/v4l-subdev6

四、驱动分析

vcm9714驱动比较简单，基于i2c总线，

核心就是要注册基于v4l2的subdev，

提供给用户层调用的核心回调函数如下：

staticconststructv4l2_ctrl_opsdw9714_vcm_ctrl_ops={.g_volatile_ctrl=dw9714_get_ctrl,.s_ctrl=dw9714_set_ctrl,};staticintdw9714_init_controls(structdw9714_device*dev_vcm){structv4l2_ctrl_handler*hdl=&dev_vcm->ctrls_vcm;conststructv4l2_ctrl_ops*ops=&dw9714_vcm_ctrl_ops;v4l2_ctrl_handler_init(hdl,1);v4l2_ctrl_new_std(hdl,ops,V4L2_CID_FOCUS_ABSOLUTE,0,VCMDRV_MAX_LOG,1,VCMDRV_MAX_LOG);……}

staticconststructv4l2_subdev_core_opsdw9714_core_ops={.ioctl=dw9714_ioctl,};staticconststructv4l2_subdev_opsdw9714_ops={.core=&dw9714_core_ops,};staticintdw9714_probe(structi2c_client*client,conststructi2c_device_id*id){v4l2_i2c_subdev_init(&dw9714_dev->sd,client,&dw9714_ops);}

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