From: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Date: Mon, 24 May 2010 13:07:49 +0000 (-0400)
Subject: Create a class and a device.
X-Git-Url: http://git.cascardo.eti.br/?p=cascardo%2Fkernel%2Fsamples%2Fchar2%2F.git;a=commitdiff_plain;h=ccfa829bd17614400d2d008c15fef13d08f242a2

Create a class and a device.
---

diff --git a/hellochar.c b/hellochar.c
index a847392..e601e38 100644
--- a/hellochar.c
+++ b/hellochar.c
@@ -25,6 +25,7 @@
 #include <linux/circ_buf.h>
 #include <linux/sched.h>
 #include <linux/completion.h>
+#include <linux/device.h>
 
 MODULE_LICENSE("GPL");
 
@@ -116,6 +117,9 @@ static const struct file_operations hello_fops = {
 	.write = hello_write,
 };
 
+static struct class *hello_class;
+static struct device *hello_dev;
+
 static int __init ch_init(void)
 {
 	int r = 0;
@@ -125,11 +129,21 @@ static int __init ch_init(void)
 		r = -ENOMEM;
 		goto out;
 	}
+	hello_class = class_create(THIS_MODULE, "hello");
+	if (IS_ERR(hello_class)) {
+		r = PTR_ERR(hello_class);
+		goto class_out;
+	}
 	memcpy(hello->buf, default_greeting, sizeof(default_greeting));
 	hello->head = sizeof(default_greeting);
 	r = alloc_chrdev_region(&devnum, 0, 256, "hello");
 	if (r)
 		goto reg_out;
+	hello_dev = device_create(hello_class, NULL, devnum, NULL, "hello");
+	if (!hello_dev) {
+		r = -ENODEV;
+		goto dev_out;
+	}
 	dev = cdev_alloc();
 	if (!dev) {
 		r = -ENOMEM;
@@ -143,8 +157,12 @@ static int __init ch_init(void)
 add_out:
 	kfree(dev);
 cdev_out:
+	device_destroy(hello_class, devnum);
+dev_out:
 	unregister_chrdev_region(devnum, 256);
 reg_out:
+	class_destroy(hello_class);
+class_out:
 	kfree(hello);
 out:
 	return r;
@@ -153,8 +171,10 @@ out:
 static void __exit ch_exit(void)
 {
 	cdev_del(dev);
+	device_destroy(hello_class, devnum);
 	unregister_chrdev_region(devnum, 256);
 	kfree(hello->buf);
+	class_destroy(hello_class);
 }
 
 module_init(ch_init);