版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/kris_fei/article/details/84796883
Platform: RK3399
OS: Android 7.1
Kernel: v4.4.83
背景：
rk3288上默认自带i2c_detect工具来探测对应I2C总线上挂载的设备以及地址。
rk3399平台默认没有开启，参考rk3288做如下修改，就可以使用了。
改动:
diff --git a/arch/arm64/configs/rockchip_eco_defconfig
b/arch/arm64/configs/rockchip_eco_defconfig
index 89b89a5..6dcba49 100644
--- a/arch/arm64/configs/rockchip_eco_defconfig
+++ b/arch/arm64/configs/rockchip_eco_defconfig
@@ -400,6 +400,8 @@ CONFIG_SERIAL_8250_DW=y
CONFIG_I2C_CHARDEV=y
CONFIG_I2C_GPIO=y
CONFIG_I2C_RK3X=y
+#Kris,181204, add i2c_detect tool.
+CONFIG_I2C_ROCKCHIP=y
CONFIG_SPI=y
CONFIG_SPI_ROCKCHIP=y
CONFIG_DEBUG_GPIO=y
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 7b0aa82..14e3bf0 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -806,6 +806,18 @@ config I2C_RK3X
This driver can also be built as a module. If so, the module will
be called i2c-rk3x.
+#Kris,181204, add i2c_detect tool.
+config I2C_ROCKCHIP
+ tristate "Rockchip I2C interface"
+ depends on ARCH_ROCKCHIP
+ help
+ If you say yes to this option, support will be included for the
+ Rockchip I2C interface.
+
+ This driver can also be built as a module. If so, the module
+ will be called i2c-rockchip.
+
+
config HAVE_S3C2410_I2C
bool
help
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 37f2819..67841e9 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -120,3 +120,6 @@ obj-$(CONFIG_I2C_XGENE_SLIMPRO) += i2c-xgene-slimpro.o
obj-$(CONFIG_SCx200_ACB) += scx200_acb.o
ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG
+
+#Kris,181204, add i2c_detect tool.
+obj-$(CONFIG_I2C_ROCKCHIP) += i2c-rockchip.o
diff --git a/drivers/i2c/busses/i2c-rockchip.c b/drivers/i2c/busses/i2c-rockchip.c
index 78bb407..df8e6c0 100644
--- a/drivers/i2c/busses/i2c-rockchip.c
+++ b/drivers/i2c/busses/i2c-rockchip.c
@@ -19,7 +19,8 @@
#include <linux/wakelock.h>
#include <linux/i2c.h>
#include <linux/of_gpio.h>
-#include <linux/of_i2c.h>
+//Kris,181204.
+//#include <linux/of_i2c.h>
#include <linux/init.h>
#include <linux/time.h>
#include <linux/interrupt.h>
@@ -733,7 +734,8 @@ static int rockchip_i2c_xfer(struct i2c_adapter *adap,
{
int ret;
struct rockchip_i2c *i2c = i2c_get_adapdata(adap);
- unsigned long scl_rate = i2c->scl_rate;
+ //Kris,181204.
+ //unsigned long scl_rate = i2c->scl_rate;
int can_sleep = !(in_atomic() || irqs_disabled());
if (can_sleep) {
@@ -931,7 +933,8 @@ static int rockchip_i2c_probe(struct platform_device *pdev)
rockchip_i2c_init_hw(i2c, 100 * 1000);
dev_info(&pdev->dev, "%s: Rockchip I2C adapter\n", dev_name(&i2c->adap.dev));
- of_i2c_register_devices(&i2c->adap);
+ //Kris,181204.
+ //of_i2c_register_devices(&i2c->adap);
mutex_init(&i2c->suspend_lock);
return 0;
@@ -1096,7 +1099,12 @@ static ssize_t i2c_detect_write(struct file *file,
return -EFAULT;
sscanf(nr_buf, "%d", &nr);
+//Kris,181204.
+#if 0
if (nr >= 5 || nr < 0)
+#else
+ if (nr > 5 || nr < 0)
+#endif
return -EFAULT;
slave_detect(nr);