kernel層porting
複製kernel driver file到相關目錄
將cm36xxx.c複製到 drivers/input/misc中
將cm36xxx.h,lightsensor.h,capella_cm3602.h複製到kernel/include/linux中
修改/arch/arm/boot/dts/qcom/下的dtsi問題
查看電路圖，看看driver它掛在什麼地方,然後找到spec看driver的i2c address。
提取信息如下：sensor掛在bus6上，i2c adress爲0x60,interrupt連接到SOC的gpio43上
因而我們可以修改相關的dtsi文件如下：
cm36xxx@60 {
compatible = "capella,cm36xxx";
reg = <0x60>;
capella,slave_address = <0x60>;
interrupt-parent = <&tlmm>;
interrupts = <43 0x2>;
capella,intrpin-gpios = <&tlmm 43 0x2>;
vio-supply = <&pm8953_l6>;
};
這裏要注意：compatible要與kernel driver中的cm36xxx_match_table中的compatible一致
###修改makefile使能夠編譯driver
修改kernel/drivers/input/misc/Makefile
obj-$(CONFIG_SENSORS_CM36656) += cm36656.o
修改kernel/drivers/input/misc/Kconfig
config SENSORS_CM36xxx
tristate “CM36xxx optical sensor”
depends on I2C
default n
help
Say Y here to enable the CM36xxx Optical Sensor.
修改kernel/arch/arm64/configs/xxxx_defconfig
CONFIG_SENSORS_CM36xxx=y
修改相關權限
注意kernel driver中的misc的name
static const struct file_operations rgbsensor_fops = {
.owner = THIS_MODULE,
.open = rgbsensor_open,
.release = rgbsensor_release,
.unlocked_ioctl = rgbsensor_ioctl,
.compat_ioctl = rgbsensor_ioctl,
};
static struct miscdevice rgbsensor_misc = {
.minor = MISC_DYNAMIC_MINOR,
.name = "asusRgbSensor",
.fops = &rgbsensor_fops
};
注意：rgb使用32位的lib因而需要compat_ioctl
修改system/core/rootdir/ueventd.rc
/dev/lightsensor 0640 system system
/dev/proximitySensor 0640 compass system
/dev/asusRgbSensor 0640 system system
修改init.rc文件
on post-fs-data
chown system system /dev/proximitySensor
chmod 0660 /dev/proximitySensor
chown system system /dev/lightsensor
chmod 0660 /dev/lightsensor
HAL層porting
這個很簡單，只要在編譯的時候能夠load android.mk即可編譯
注意open的目錄名字與設備名字要相同
編譯改錯
一般廠商給的demo code在編譯時都會出一些錯誤，因而需要我們BSP進行修正。這邊會在後續的博客中解釋。
debug的一些方法
查看電是否porting正常
cd sys/kernel/debug/regulator/
找到用哪個電，然後cat consumers
查看I2C是否掛起
adb shell訪問/sys/class/i2c-adapter/i2c-X（X代表對應的I2C bus）目錄，確認已經建立了X-00yy（yy代表slave address）