From e2bfb94a7590323e3314a9742f59b7faa3a9b2ad Mon Sep 17 00:00:00 2001
From: zeroway <M_O_Bz@163.com>
Date: Fri, 30 Nov 2018 09:57:45 +0800
Subject: [PATCH] I2C : set/get chip data

---
 debug/i2c/Makefile   | 14 ++++++++------
 debug/i2c/myi2c.c    | 42 +++++++++++++++++++++++++++---------------
 debug/i2c/myi2c.dtsi |  7 +++++++
 3 files changed, 42 insertions(+), 21 deletions(-)
 create mode 100644 debug/i2c/myi2c.dtsi

diff --git a/debug/i2c/Makefile b/debug/i2c/Makefile
index 447a5fc..b3c143f 100644
--- a/debug/i2c/Makefile
+++ b/debug/i2c/Makefile
@@ -3,9 +3,9 @@
 # DEBUG = y
 
 # Usage
-# make CC=<your_compiler_path> KERNELDIR=<your_kernel_dir>
+# make CROSS_COMPILE=<cross_compiler_prefix> KERNEL_DIR=<your_kernel_dir> KERNEL_BUID_OUTPUT=<kernel_buid_output>
 #
-# make CC=/home/zeroway/3288/src/3288_4.4/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/bin/arm-eabi-gcc KERNELDIR=/home/zeroway/3288/src/3288_4.4/kernel
+# make CROSS_COMPILE=/home/zeroway/3288/51/src/3288_5.1_v2/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/bin/arm-eabi- KERNEL_DIR=/home/zeroway/3288/51/src/3288_5.1_v2/kernel KERNEL_BUID_OUTPUT=/home/zeroway/3288/51/src/3288_5.1_v2/out/target/product/rk3288/obj/KERNEL
 
 # Add your debugging flag (or not) to CFLAGS
 ifeq ($(DEBUG),y)
@@ -15,13 +15,15 @@ DEBFLAGS = -O2
 endif
 
 obj-m := myi2c.o
-obj-m += i2c_regmap.o
-KERNELDIR ?= /lib/modules/$(shell uname -r)/build
-CC ?= gcc
+
+KERNEL_DIR ?= /lib/modules/$(shell uname -r)/build
+KERNEL_BUID_OUTPUT ?=$(KERNEL_DIR)
+CC = $(CROSS_COMPILE)gcc
+LD = $(CROSS_COMPILE)ld
 PWD := $(shell pwd)
 
 modules:
-	$(MAKE) -C $(KERNELDIR) M=$(PWD) modules
+	$(MAKE) -C $(KERNEL_DIR) M=$(PWD) O=$(KERNEL_BUID_OUTPUT) modules
 
 clean:
 	rm -rf *.o *~ core .depend .*.cmd *.ko *.mod.c .tmp_versions modules.order Module.symvers
diff --git a/debug/i2c/myi2c.c b/debug/i2c/myi2c.c
index d598ee1..bfe2b51 100644
--- a/debug/i2c/myi2c.c
+++ b/debug/i2c/myi2c.c
@@ -4,20 +4,10 @@
 #include <linux/delay.h>
 #include <linux/slab.h>
 
-/* describe in device tree */
-#if 0
-&i2c {
-	myi2c@36 {
-		compatible = "myi2c";
-		status = "okay";
-		reg = <0x36>;
-	};
-}
-#endif
-
 struct myi2c_chip {
+	char name[20];
 	struct i2c_client	*client;
-	struct device		*dev;
+	struct device		dev;
 };
 
 static inline int __myi2c_read(struct i2c_client *client,
@@ -32,6 +22,7 @@ static inline int __myi2c_read(struct i2c_client *client,
 	}
 
 	*val = (uint8_t)ret;
+
 	return 0;
 }
 
@@ -65,8 +56,17 @@ static ssize_t myi2c_debug_show(struct device *dev,
 				 char *buf)
 {
     uint8_t val;
-	myi2c_read(dev,myi2c_regs_addr,&val);
-	return sprintf(buf,"REG[%x]=0x%x\n",myi2c_regs_addr,val);
+	struct i2c_client *client;
+	struct myi2c_chip *chip;
+
+	/* get chip */
+	client = container_of(dev, struct i2c_client, dev);
+	chip = i2c_get_clientdata(client);
+	printk("chip name = %s\n", chip->name);
+
+	myi2c_read(dev, myi2c_regs_addr, &val);
+
+	return sprintf(buf, "REG[%x]=0x%x\n", myi2c_regs_addr, val);
 }
 
 static ssize_t myi2c_debug_store(struct device *dev,
@@ -74,11 +74,20 @@ static ssize_t myi2c_debug_store(struct device *dev,
 {
 	int tmp;
 	uint8_t val;
+	struct i2c_client *client;
+	struct myi2c_chip *chip;
+
+	/* get chip */
+	client = container_of(dev, struct i2c_client, dev);
+	chip = i2c_get_clientdata(client);
+	printk("chip name = %s\n", chip->name);
+
 	tmp = simple_strtoul(buf, NULL, 16);
 	/* val = low 8 bit, addr = high 8 bit */
 	val = tmp & 0x00FF;
 	myi2c_regs_addr= (tmp >> 8) & 0x00FF;
 	myi2c_write(dev, myi2c_regs_addr, val);
+
 	return count;
 }
 
@@ -119,7 +128,7 @@ static int myi2c_probe(struct i2c_client *client,
 	}
 
 	chip->client = client;
-	chip->dev = &client->dev;
+	strcpy(chip->name, "I2C_chip");
 	i2c_set_clientdata(client, chip);
 
 	ret = sysfs_create_group(&client->dev.kobj, &myi2c_attr_group);
@@ -135,6 +144,7 @@ static int myi2c_probe(struct i2c_client *client,
 static int myi2c_remove(struct i2c_client *client)
 {
 	struct myi2c_chip *chip = i2c_get_clientdata(client);
+
 	sysfs_remove_group(&client->dev.kobj, &myi2c_attr_group);
 	kfree(chip);
 
@@ -160,7 +170,9 @@ static struct i2c_driver myi2c_driver = {
 static int myi2c_init(void)
 {
 	int ret;
+
 	ret = i2c_add_driver(&myi2c_driver);
+
 	return ret;
 }
 
diff --git a/debug/i2c/myi2c.dtsi b/debug/i2c/myi2c.dtsi
new file mode 100644
index 0000000..6c76218
--- /dev/null
+++ b/debug/i2c/myi2c.dtsi
@@ -0,0 +1,7 @@
+&i2c0 {
+	myi2c@36 {
+		compatible = "myi2c";
+		status = "okay";
+		reg = <0x36>;
+	};
+};