#include <linux/init.h>
#include <linux/types.h>
+#include <linux/idr.h>
#include <linux/input/mt.h>
#include <linux/module.h>
#include <linux/slab.h>
MODULE_DESCRIPTION("Input core");
MODULE_LICENSE("GPL");
-#define INPUT_DEVICES 256
+#define INPUT_MAX_CHAR_DEVICES 1024
+#define INPUT_FIRST_DYNAMIC_DEV 256
+static DEFINE_IDA(input_ida);
static LIST_HEAD(input_dev_list);
static LIST_HEAD(input_handler_list);
*/
static DEFINE_MUTEX(input_mutex);
-static struct input_handler *input_table[8];
-
static const struct input_value input_value_sync = { EV_SYN, SYN_REPORT, 1 };
static inline int is_event_supported(unsigned int code,
seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
if (handler->filter)
seq_puts(seq, " (filter)");
- if (handler->fops)
+ if (handler->legacy_minors)
seq_printf(seq, " Minor=%d", handler->minor);
seq_putc(seq, '\n');
int input_register_handler(struct input_handler *handler)
{
struct input_dev *dev;
- int retval;
+ int error;
- retval = mutex_lock_interruptible(&input_mutex);
- if (retval)
- return retval;
+ error = mutex_lock_interruptible(&input_mutex);
+ if (error)
+ return error;
INIT_LIST_HEAD(&handler->h_list);
- if (handler->fops != NULL) {
- if (input_table[handler->minor >> 5]) {
- retval = -EBUSY;
- goto out;
- }
- input_table[handler->minor >> 5] = handler;
- }
-
list_add_tail(&handler->node, &input_handler_list);
list_for_each_entry(dev, &input_dev_list, node)
input_wakeup_procfs_readers();
- out:
mutex_unlock(&input_mutex);
- return retval;
+ return 0;
}
EXPORT_SYMBOL(input_register_handler);
list_del_init(&handler->node);
- if (handler->fops != NULL)
- input_table[handler->minor >> 5] = NULL;
-
input_wakeup_procfs_readers();
mutex_unlock(&input_mutex);
}
EXPORT_SYMBOL(input_unregister_handle);
-static int input_open_file(struct inode *inode, struct file *file)
+/**
+ * input_get_new_minor - allocates a new input minor number
+ * @legacy_base: beginning or the legacy range to be searched
+ * @legacy_num: size of legacy range
+ * @allow_dynamic: whether we can also take ID from the dynamic range
+ *
+ * This function allocates a new device minor for from input major namespace.
+ * Caller can request legacy minor by specifying @legacy_base and @legacy_num
+ * parameters and whether ID can be allocated from dynamic range if there are
+ * no free IDs in legacy range.
+ */
+int input_get_new_minor(int legacy_base, unsigned int legacy_num,
+ bool allow_dynamic)
{
- struct input_handler *handler;
- const struct file_operations *old_fops, *new_fops = NULL;
- int err;
-
- err = mutex_lock_interruptible(&input_mutex);
- if (err)
- return err;
-
- /* No load-on-demand here? */
- handler = input_table[iminor(inode) >> 5];
- if (handler)
- new_fops = fops_get(handler->fops);
-
- mutex_unlock(&input_mutex);
-
/*
- * That's _really_ odd. Usually NULL ->open means "nothing special",
- * not "no device". Oh, well...
+ * This function should be called from input handler's ->connect()
+ * methods, which are serialized with input_mutex, so no additional
+ * locking is needed here.
*/
- if (!new_fops || !new_fops->open) {
- fops_put(new_fops);
- err = -ENODEV;
- goto out;
+ if (legacy_base >= 0) {
+ int minor = ida_simple_get(&input_ida,
+ legacy_base,
+ legacy_base + legacy_num,
+ GFP_KERNEL);
+ if (minor >= 0 || !allow_dynamic)
+ return minor;
}
- old_fops = file->f_op;
- file->f_op = new_fops;
-
- err = new_fops->open(inode, file);
- if (err) {
- fops_put(file->f_op);
- file->f_op = fops_get(old_fops);
- }
- fops_put(old_fops);
-out:
- return err;
+ return ida_simple_get(&input_ida,
+ INPUT_FIRST_DYNAMIC_DEV, INPUT_MAX_CHAR_DEVICES,
+ GFP_KERNEL);
}
+EXPORT_SYMBOL(input_get_new_minor);
-static const struct file_operations input_fops = {
- .owner = THIS_MODULE,
- .open = input_open_file,
- .llseek = noop_llseek,
-};
+/**
+ * input_free_minor - release previously allocated minor
+ * @minor: minor to be released
+ *
+ * This function releases previously allocated input minor so that it can be
+ * reused later.
+ */
+void input_free_minor(unsigned int minor)
+{
+ ida_simple_remove(&input_ida, minor);
+}
+EXPORT_SYMBOL(input_free_minor);
static int __init input_init(void)
{
if (err)
goto fail1;
- err = register_chrdev(INPUT_MAJOR, "input", &input_fops);
+ err = register_chrdev_region(MKDEV(INPUT_MAJOR, 0),
+ INPUT_MAX_CHAR_DEVICES, "input");
if (err) {
pr_err("unable to register char major %d", INPUT_MAJOR);
goto fail2;
static void __exit input_exit(void)
{
input_proc_exit();
- unregister_chrdev(INPUT_MAJOR, "input");
+ unregister_chrdev_region(MKDEV(INPUT_MAJOR, 0),
+ INPUT_MAX_CHAR_DEVICES);
class_unregister(&input_class);
}
projects / ~andy / linux / blobdiff