androidi2c读写,Android平台下使用i2ctools

Android 平台下使用 i2c-tools

Andorid 开发板为 Freescale imx6 的 SabreSD Board

下载源码

将 i2c-tools 代码下载到 Android 源码的 external 目录下&＃xff0c;我是使用 Subversion 直接从官方版本库中检出&＃xff0c;当然使用别的方式下载到源代码也是可以的。

&＃xff5e;/mydroid $ svn checkout http://lm-sensors.org/svn/i2c-tools/branches/i2c-tools-3.1 external/i2c-tools

在 i2c-tools 目录下新建 Android.mk 文件&＃xff0c;内容如下&＃xff1a;

# external/i2c-tools/Android.mk

LOCAL_PATH:&＃61; $(call my-dir)

include $(CLEAR_VARS)

LOCAL_MODULE_TAGS :&＃61; eng

LOCAL_C_INCLUDES &＃43;&＃61; $(LOCAL_PATH) $(LOCAL_PATH)/$(KERNEL_DIR)/include

LOCAL_SRC_FILES :&＃61; tools/i2cbusses.c tools/util.c

LOCAL_MODULE :&＃61; i2c-tools

include $(BUILD_STATIC_LIBRARY)

include $(CLEAR_VARS)

LOCAL_MODULE_TAGS :&＃61; eng

LOCAL_SRC_FILES:&＃61;tools/i2cdetect.c

LOCAL_MODULE:&＃61;i2cdetect

LOCAL_CPPFLAGS &＃43;&＃61; -DANDROID

LOCAL_SHARED_LIBRARIES:&＃61;libc

LOCAL_STATIC_LIBRARIES :&＃61; i2c-tools

LOCAL_C_INCLUDES &＃43;&＃61; $(LOCAL_PATH) $(LOCAL_PATH)/$(KERNEL_DIR)/include

include $(BUILD_EXECUTABLE)

include $(CLEAR_VARS)

LOCAL_MODULE_TAGS :&＃61; eng

LOCAL_SRC_FILES:&＃61;tools/i2cget.c

LOCAL_MODULE:&＃61;i2cget

LOCAL_CPPFLAGS &＃43;&＃61; -DANDROID

LOCAL_SHARED_LIBRARIES:&＃61;libc

LOCAL_STATIC_LIBRARIES :&＃61; i2c-tools

LOCAL_C_INCLUDES &＃43;&＃61; $(LOCAL_PATH) $(LOCAL_PATH)/$(KERNEL_DIR)/include

include $(BUILD_EXECUTABLE)

include $(CLEAR_VARS)

LOCAL_MODULE_TAGS :&＃61; eng

LOCAL_SRC_FILES:&＃61;tools/i2cset.c

LOCAL_MODULE:&＃61;i2cset

LOCAL_CPPFLAGS &＃43;&＃61; -DANDROID

LOCAL_SHARED_LIBRARIES:&＃61;libc

LOCAL_STATIC_LIBRARIES :&＃61; i2c-tools

LOCAL_C_INCLUDES &＃43;&＃61; $(LOCAL_PATH) $(LOCAL_PATH)/$(KERNEL_DIR)/include

include $(BUILD_EXECUTABLE)

include $(CLEAR_VARS)

LOCAL_MODULE_TAGS :&＃61; eng

LOCAL_SRC_FILES:&＃61;tools/i2cdump.c

LOCAL_MODULE:&＃61;i2cdump

LOCAL_CPPFLAGS &＃43;&＃61; -DANDROID

LOCAL_SHARED_LIBRARIES:&＃61;libc

LOCAL_STATIC_LIBRARIES :&＃61; i2c-tools

LOCAL_C_INCLUDES &＃43;&＃61; $(LOCAL_PATH) $(LOCAL_PATH)/$(KERNEL_DIR)/include

include $(BUILD_EXECUTABLE)

编译

~/mydroid/external/i2c-tools $ mm

编译后在 out/target/product/sabresd_6dq/system/bin目录下生成4个可执行程序:

i2cdetect

i2cdump

i2cget

i2cset

安装

制作新的 system image&＃xff0c;然后重新烧录 system.img

~/mydroid $ make snod

~/mydroid $ fastboot system out/target/product/sabresd_6dq/system.img

当然也可以通过 adb push 之间将编译生成的4个文件复制到 Android 平台的 /system/bin 目录下。 在 abd pusll 之前&＃xff0c;要先将 system 分区 remount 成可写入模式。

i2c-tools 的用法

i2cdetect

列举 I2C bus

# i2cdetect -l

i2c-0 i2c imx-i2c I2C adapter

i2c-1 i2c imx-i2c I2C adapter

i2c-2 i2c imx-i2c I2C adapter

列举 I2C bus i2c-1 上面连接的所有设备

# i2cdetect -y 1

0 1 2 3 4 5 6 7 8 9 a b c d e f

00: -- -- -- -- -- UU -- -- -- -- -- -- --

10: -- UU -- -- -- -- -- -- -- -- -- -- -- -- -- --

20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

30: -- -- -- -- -- -- -- -- -- -- 3a -- -- -- -- --

40: -- -- -- -- -- -- -- -- UU -- -- -- -- -- -- --

50: UU -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

70: -- -- -- -- -- -- -- --

发现 I2C 设备的位置显示为UU或者表示设备地址的数值&＃xff0c;UU表示该设备在 driver 中被使用。

i2cdump

dump I2C 设备大批量 register 的值

# i2cdump -y -f 1 0x3a

No size specified (using byte-data access)

0 1 2 3 4 5 6 7 8 9 a b c d e f 0123456789abcdef

00: eb 00 7f 05 3d 00 00 00 08 06 00 00 00 00 00 00 ?.??&＃61;...??......

10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

20: 01 23 45 67 89 ab cd ef fe dc ba 98 76 54 32 10 ?#Eg????????vT2?

30: f0 e1 d2 c3 00 00 00 00 00 00 00 00 00 00 00 00 ????............

40: 80 00 10 00 00 00 00 00 00 00 00 00 00 00 00 00 ?.?.............

50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

60: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

f0: 00 00 00 00 00 00 00 00 00 00 00 30 00 00 00 00 ...........0....

i2cget

读取 I2C 设备某个 register 的值

# i2cget -y -f 1 0x3a 0x02

0x7f

i2cset

设置 I2C 设备某个 register 的值

# i2cset -y -f 1 0x3a 0x02 0x05