diff options
| author | Kay Sievers <kay.sievers@vrfy.org> | 2010-12-01 18:51:05 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-12-16 16:15:34 -0800 |
| commit | fbc92a3455577ab17615cbcb91826399061bd789 (patch) | |
| tree | 0f47703d9d3b40969e007a6d27a1b603cdff43da /drivers/tty/vt | |
| parent | 35c64e5d13c3d7d8c4ad061ad5e20498b9160c24 (diff) | |
tty: add 'active' sysfs attribute to tty0 and console device
tty: add 'active' sysfs attribute to tty0 and console device
Userspace can query the actual virtual console, and the configured
console devices behind /dev/tt0 and /dev/console.
The last entry in the list of devices is the active device, analog
to the console= kernel command line option.
The attribute supports poll(), which is raised when the virtual
console is changed or /dev/console is reconfigured.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
index 0000000..b138b66
Diffstat (limited to 'drivers/tty/vt')
| -rw-r--r-- | drivers/tty/vt/vt.c | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index a8ec48ed14d..76407eca9ab 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -236,6 +236,14 @@ enum { }; /* + * /sys/class/tty/tty0/ + * + * the attribute 'active' contains the name of the current vc + * console and it supports poll() to detect vc switches + */ +static struct device *tty0dev; + +/* * Notifier list for console events. */ static ATOMIC_NOTIFIER_HEAD(vt_notifier_list); @@ -688,6 +696,8 @@ void redraw_screen(struct vc_data *vc, int is_switch) save_screen(old_vc); set_origin(old_vc); } + if (tty0dev) + sysfs_notify(&tty0dev->kobj, NULL, "active"); } else { hide_cursor(vc); redraw = 1; @@ -2967,13 +2977,24 @@ static const struct tty_operations con_ops = { static struct cdev vc0_cdev; +static ssize_t show_tty_active(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "tty%d\n", fg_console + 1); +} +static DEVICE_ATTR(active, S_IRUGO, show_tty_active, NULL); + int __init vty_init(const struct file_operations *console_fops) { cdev_init(&vc0_cdev, console_fops); if (cdev_add(&vc0_cdev, MKDEV(TTY_MAJOR, 0), 1) || register_chrdev_region(MKDEV(TTY_MAJOR, 0), 1, "/dev/vc/0") < 0) panic("Couldn't register /dev/tty0 driver\n"); - device_create(tty_class, NULL, MKDEV(TTY_MAJOR, 0), NULL, "tty0"); + tty0dev = device_create(tty_class, NULL, MKDEV(TTY_MAJOR, 0), NULL, "tty0"); + if (IS_ERR(tty0dev)) + tty0dev = NULL; + else + device_create_file(tty0dev, &dev_attr_active); vcs_init(); |