[PATCH] add sysfs vc device support [4/4]

[PATCH] add sysfs vc device support [4/4]

[Greg KH]

This adds /sys/class/vc which enables all vc char devices to show up
properly in udev.

Has been posted to lkml a few times in the past and tested by a wide
range of people.


diff -Nru a/drivers/char/vc_screen.c b/drivers/char/vc_screen.c
--- a/drivers/char/vc_screen.c	Mon Dec 22 16:02:06 2003
+++ b/drivers/char/vc_screen.c	Mon Dec 22 16:02:06 2003
@@ -36,6 +36,7 @@
 #include <linux/kbd_kern.h>
 #include <linux/console.h>
 #include <linux/smp_lock.h>
+#include <linux/device.h>
 #include <asm/uaccess.h>
 #include <asm/byteorder.h>
 #include <asm/unaligned.h>
@@ -469,6 +470,85 @@
 	.open		= vcs_open,
 };
 
+/* vc class implementation */
+
+struct vc_dev {
+	struct list_head node;
+	dev_t dev;
+	struct class_device class_dev;
+};
+#define to_vc_dev(d) container_of(d, struct vc_dev, class_dev)
+
+static LIST_HEAD(vc_dev_list);
+static spinlock_t vc_dev_list_lock = SPIN_LOCK_UNLOCKED;
+
+static void release_vc_dev(struct class_device *class_dev)
+{
+	struct vc_dev *vc_dev = to_vc_dev(class_dev);
+	kfree(vc_dev);
+}
+
+static struct class vc_class = {
+	.name		= "vc",
+	.release	= &release_vc_dev,
+};
+
+static ssize_t show_dev(struct class_device *class_dev, char *buf)
+{
+	struct vc_dev *vc_dev = to_vc_dev(class_dev);
+	return print_dev_t(buf, vc_dev->dev);
+}
+static CLASS_DEVICE_ATTR(dev, S_IRUGO, show_dev, NULL);
+
+static int vc_add_class_device(dev_t dev, char *name, int minor)
+{
+	struct vc_dev *vc_dev = NULL;
+	int retval;
+
+	vc_dev = kmalloc(sizeof(*vc_dev), GFP_KERNEL);
+	if (!vc_dev)
+		return -ENOMEM;
+	memset(vc_dev, 0x00, sizeof(*vc_dev));
+
+	vc_dev->dev = dev;
+	vc_dev->class_dev.class = &vc_class;
+	snprintf(vc_dev->class_dev.class_id, BUS_ID_SIZE, name, minor);
+	retval = class_device_register(&vc_dev->class_dev);
+	if (retval)
+		goto error;
+	class_device_create_file(&vc_dev->class_dev, &class_device_attr_dev);
+	spin_lock(&vc_dev_list_lock);
+	list_add(&vc_dev->node, &vc_dev_list);
+	spin_unlock(&vc_dev_list_lock);
+	return 0;
+error:
+	kfree(vc_dev);
+	return retval;
+}
+
+static void vc_remove_class_device(int minor)
+{
+	struct vc_dev *vc_dev = NULL;
+	struct list_head *tmp;
+	int found = 0;
+
+	spin_lock(&vc_dev_list_lock);
+	list_for_each(tmp, &vc_dev_list) {
+		vc_dev = list_entry(tmp, struct vc_dev, node);
+		if (MINOR(vc_dev->dev) = minor) {
+			found = 1;
+			break;
+		}
+	}
+	if (found) {
+		list_del(&vc_dev->node);
+		spin_unlock(&vc_dev_list_lock);
+		class_device_unregister(&vc_dev->class_dev);
+	} else {
+		spin_unlock(&vc_dev_list_lock);
+	}
+}
+
 void vcs_make_devfs(struct tty_struct *tty)
 {
 	devfs_mk_cdev(MKDEV(VCS_MAJOR, tty->index + 1),
@@ -477,19 +557,26 @@
 	devfs_mk_cdev(MKDEV(VCS_MAJOR, tty->index + 129),
 			S_IFCHR|S_IRUSR|S_IWUSR,
 			"vcc/a%u", tty->index + 1);
+	vc_add_class_device(MKDEV(VCS_MAJOR, tty->index + 1), "vcs%u", tty->index + 1);
+	vc_add_class_device(MKDEV(VCS_MAJOR, tty->index + 129), "vcsa%u", tty->index + 1);
 }
 void vcs_remove_devfs(struct tty_struct *tty)
 {
 	devfs_remove("vcc/%u", tty->index + 1);
 	devfs_remove("vcc/a%u", tty->index + 1);
+	vc_remove_class_device(tty->index + 1);
+	vc_remove_class_device(tty->index + 129);
 }
 
 int __init vcs_init(void)
 {
 	if (register_chrdev(VCS_MAJOR, "vcs", &vcs_fops))
 		panic("unable to get major %d for vcs device", VCS_MAJOR);
+	class_register(&vc_class);
 
 	devfs_mk_cdev(MKDEV(VCS_MAJOR, 0), S_IFCHR|S_IRUSR|S_IWUSR, "vcc/0");
 	devfs_mk_cdev(MKDEV(VCS_MAJOR, 128), S_IFCHR|S_IRUSR|S_IWUSR, "vcc/a0");
+	vc_add_class_device(MKDEV(VCS_MAJOR, 0), "vcs", 0);
+	vc_add_class_device(MKDEV(VCS_MAJOR, 128), "vcsa", 128);
 	return 0;
 }


-------------------------------------------------------
This SF.net email is sponsored by: IBM Linux Tutorials.
Become an expert in LINUX or just sharpen your skills.  Sign up for IBM's
Free Linux Tutorials.  Learn everything from the bash shell to sys admin.
Click now! http://ads.osdn.com/?ad_id\x1278&alloc_id371&op=click
_______________________________________________
Linux-hotplug-devel mailing list  http://linux-hotplug.sourceforge.net
Linux-hotplug-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel

Re: [PATCH] add sysfs vc device support [4/4]

[Christoph Hellwig]

On Mon, Dec 22, 2003 at 04:28:51PM -0800, Greg KH wrote:
> This adds /sys/class/vc which enables all vc char devices to show up
> properly in udev.
> 
> Has been posted to lkml a few times in the past and tested by a wide
> range of people.

Same thing agin.  This is virtual console code and shouldn't be
in sysfs.

Also pasting the same code n times into different subsystems isn't
exactly a good sign of code reuse..


-------------------------------------------------------
This SF.net email is sponsored by: IBM Linux Tutorials.
Become an expert in LINUX or just sharpen your skills.  Sign up for IBM's
Free Linux Tutorials.  Learn everything from the bash shell to sys admin.
Click now! http://ads.osdn.com/?ad_id\x1278&alloc_id371&op=click
_______________________________________________
Linux-hotplug-devel mailing list  http://linux-hotplug.sourceforge.net
Linux-hotplug-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel