[PATCH 2/5] VT binding: Add sysfs support
STALE7421d
From: "Antonino A. Daplas" <adaplas@gmail.com>
Date: 2006-06-09 08:43:35
Also in:
lkml
Subsystem:
char and misc drivers, the rest, tty layer and serial drivers · Maintainers:
Arnd Bergmann, Greg Kroah-Hartman, Linus Torvalds, Jiri Slaby
Add sysfs attributes for binding and unbinding VT console drivers. The
attributes are located in /sys/class/tty/console and are namely:
A. backend - list registered drivers in the following format:
"I C: Description"
Where: I = ID number of the driver
C = status of the driver which can be:
S = system driver
B = bound modular driver
U = unbound modular driver
Description - text description of the driver
B. bind - binds a driver to the console layer
echo <ID> > /sys/class/tty/console/bind
C. unbind - unbinds a driver from the console layer
echo <ID> > /sys/class/tty/console/unbind
The tty layer does nothing to these attributes except create them and punt all
requests to the VT layer.
Signed-off-by: Antonino Daplas <pol.net>
---
drivers/char/tty_io.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++-
include/linux/tty.h | 19 ++++++++++++++++++
2 files changed, 71 insertions(+), 1 deletions(-)
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index a5730a6..e23d360 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c@@ -3231,6 +3231,47 @@ #ifdef CONFIG_VT static struct cdev vc0_cdev; #endif +static ssize_t store_bind(struct class_device *class_device, + const char *buf, size_t count) +{ + int index = simple_strtoul(buf, NULL, 0); + + vt_bind(index); + return count; +} + +static ssize_t store_unbind(struct class_device *class_device, + const char *buf, size_t count) +{ + int index = simple_strtoul(buf, NULL, 0); + + vt_unbind(index); + return count; +} + +static ssize_t show_con_drivers(struct class_device *class_device, char *buf) +{ + return vt_show_drivers(buf); +} + +static struct class_device_attribute class_device_attrs[] = { + __ATTR(bind, S_IWUSR, NULL, store_bind), + __ATTR(unbind, S_IWUSR, NULL, store_unbind), + __ATTR(backend, S_IRUGO, show_con_drivers, NULL), +}; + +static struct class_device *console_class_device; + +static int console_init_class_device(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(class_device_attrs); i++) + class_device_create_file(console_class_device, + &class_device_attrs[i]); + return 0; +} + /* * Ok, now we can initialize the rest of the tty devices and can count * on memory allocations, interrupts etc..
@@ -3249,7 +3290,17 @@ static int __init tty_init(void) register_chrdev_region(MKDEV(TTYAUX_MAJOR, 1), 1, "/dev/console") < 0) panic("Couldn't register /dev/console driver\n"); devfs_mk_cdev(MKDEV(TTYAUX_MAJOR, 1), S_IFCHR|S_IRUSR|S_IWUSR, "console"); - class_device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 1), NULL, "console"); + console_class_device = class_device_create(tty_class, NULL, + MKDEV(TTYAUX_MAJOR, 1), + NULL, "console"); + if (IS_ERR(console_class_device)) { + printk(KERN_WARNING "Unable to create class device " + "for console; errno = %ldn", + PTR_ERR(console_class_device)); + console_class_device = NULL; + } else + console_init_class_device(); + #ifdef CONFIG_UNIX98_PTYS cdev_init(&ptmx_cdev, &ptmx_fops);
diff --git a/include/linux/tty.h b/include/linux/tty.h
index cb35ca5..3edaa5d 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h@@ -347,6 +347,25 @@ extern void console_print(const char *); extern int vt_ioctl(struct tty_struct *tty, struct file * file, unsigned int cmd, unsigned long arg); +#ifdef CONFIG_VT +extern int vt_bind(int index); +extern int vt_unbind(int index); +extern int vt_show_drivers(char *buf); +#else +static inline int vt_bind(int index) +{ + return 0; +} +static inline int vt_unbind(int index) +{ + return 0; +} +static inline int vt_show_drivers(char *buf) +{ + return 0; +} +#endif + static inline dev_t tty_devnum(struct tty_struct *tty) { return MKDEV(tty->driver->major, tty->driver->minor_start) + tty->index;