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path: root/drivers/input/evdev.c
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Diffstat (limited to 'drivers/input/evdev.c')
-rw-r--r--drivers/input/evdev.c99
1 files changed, 33 insertions, 66 deletions
diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index 118d0300f1fb..6ae2ac47c9c8 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -23,11 +23,11 @@
#include <linux/input/mt.h>
#include <linux/major.h>
#include <linux/device.h>
+#include <linux/cdev.h>
#include "input-compat.h"
struct evdev {
int open;
- int minor;
struct input_handle handle;
wait_queue_head_t wait;
struct evdev_client __rcu *grab;
@@ -35,6 +35,7 @@ struct evdev {
spinlock_t client_lock; /* protects client_list */
struct mutex mutex;
struct device dev;
+ struct cdev cdev;
bool exist;
};
@@ -51,9 +52,6 @@ struct evdev_client {
struct input_event buffer[];
};
-static struct evdev *evdev_table[EVDEV_MINORS];
-static DEFINE_MUTEX(evdev_table_mutex);
-
static void __pass_event(struct evdev_client *client,
const struct input_event *event)
{
@@ -310,35 +308,16 @@ static unsigned int evdev_compute_buffer_size(struct input_dev *dev)
static int evdev_open(struct inode *inode, struct file *file)
{
- struct evdev *evdev;
+ struct evdev *evdev = container_of(inode->i_cdev, struct evdev, cdev);
+ unsigned int bufsize = evdev_compute_buffer_size(evdev->handle.dev);
struct evdev_client *client;
- int i = iminor(inode) - EVDEV_MINOR_BASE;
- unsigned int bufsize;
int error;
- if (i >= EVDEV_MINORS)
- return -ENODEV;
-
- error = mutex_lock_interruptible(&evdev_table_mutex);
- if (error)
- return error;
- evdev = evdev_table[i];
- if (evdev)
- get_device(&evdev->dev);
- mutex_unlock(&evdev_table_mutex);
-
- if (!evdev)
- return -ENODEV;
-
- bufsize = evdev_compute_buffer_size(evdev->handle.dev);
-
client = kzalloc(sizeof(struct evdev_client) +
bufsize * sizeof(struct input_event),
GFP_KERNEL);
- if (!client) {
- error = -ENOMEM;
- goto err_put_evdev;
- }
+ if (!client)
+ return -ENOMEM;
client->bufsize = bufsize;
spin_lock_init(&client->buffer_lock);
@@ -352,13 +331,12 @@ static int evdev_open(struct inode *inode, struct file *file)
file->private_data = client;
nonseekable_open(inode, file);
+ get_device(&evdev->dev);
return 0;
err_free_client:
evdev_detach_client(evdev, client);
kfree(client);
- err_put_evdev:
- put_device(&evdev->dev);
return error;
}
@@ -942,26 +920,6 @@ static const struct file_operations evdev_fops = {
.llseek = no_llseek,
};
-static int evdev_install_chrdev(struct evdev *evdev)
-{
- /*
- * No need to do any locking here as calls to connect and
- * disconnect are serialized by the input core
- */
- evdev_table[evdev->minor] = evdev;
- return 0;
-}
-
-static void evdev_remove_chrdev(struct evdev *evdev)
-{
- /*
- * Lock evdev table to prevent race with evdev_open()
- */
- mutex_lock(&evdev_table_mutex);
- evdev_table[evdev->minor] = NULL;
- mutex_unlock(&evdev_table_mutex);
-}
-
/*
* Mark device non-existent. This disables writes, ioctls and
* prevents new users from opening the device. Already posted
@@ -980,7 +938,8 @@ static void evdev_cleanup(struct evdev *evdev)
evdev_mark_dead(evdev);
evdev_hangup(evdev);
- evdev_remove_chrdev(evdev);
+
+ cdev_del(&evdev->cdev);
/* evdev is marked dead so no one else accesses evdev->open */
if (evdev->open) {
@@ -991,43 +950,47 @@ static void evdev_cleanup(struct evdev *evdev)
/*
* Create new evdev device. Note that input core serializes calls
- * to connect and disconnect so we don't need to lock evdev_table here.
+ * to connect and disconnect.
*/
static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
const struct input_device_id *id)
{
struct evdev *evdev;
int minor;
+ int dev_no;
int error;
- for (minor = 0; minor < EVDEV_MINORS; minor++)
- if (!evdev_table[minor])
- break;
-
- if (minor == EVDEV_MINORS) {
- pr_err("no more free evdev devices\n");
- return -ENFILE;
+ minor = input_get_new_minor(EVDEV_MINOR_BASE, EVDEV_MINORS, true);
+ if (minor < 0) {
+ error = minor;
+ pr_err("failed to reserve new minor: %d\n", error);
+ return error;
}
evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
- if (!evdev)
- return -ENOMEM;
+ if (!evdev) {
+ error = -ENOMEM;
+ goto err_free_minor;
+ }
INIT_LIST_HEAD(&evdev->client_list);
spin_lock_init(&evdev->client_lock);
mutex_init(&evdev->mutex);
init_waitqueue_head(&evdev->wait);
-
- dev_set_name(&evdev->dev, "event%d", minor);
evdev->exist = true;
- evdev->minor = minor;
+
+ dev_no = minor;
+ /* Normalize device number if it falls into legacy range */
+ if (dev_no < EVDEV_MINOR_BASE + EVDEV_MINORS)
+ dev_no -= EVDEV_MINOR_BASE;
+ dev_set_name(&evdev->dev, "event%d", dev_no);
evdev->handle.dev = input_get_device(dev);
evdev->handle.name = dev_name(&evdev->dev);
evdev->handle.handler = handler;
evdev->handle.private = evdev;
- evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor);
+ evdev->dev.devt = MKDEV(INPUT_MAJOR, minor);
evdev->dev.class = &input_class;
evdev->dev.parent = &dev->dev;
evdev->dev.release = evdev_free;
@@ -1037,7 +1000,8 @@ static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
if (error)
goto err_free_evdev;
- error = evdev_install_chrdev(evdev);
+ cdev_init(&evdev->cdev, &evdev_fops);
+ error = cdev_add(&evdev->cdev, evdev->dev.devt, 1);
if (error)
goto err_unregister_handle;
@@ -1053,6 +1017,8 @@ static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
input_unregister_handle(&evdev->handle);
err_free_evdev:
put_device(&evdev->dev);
+ err_free_minor:
+ input_free_minor(minor);
return error;
}
@@ -1062,6 +1028,7 @@ static void evdev_disconnect(struct input_handle *handle)
device_del(&evdev->dev);
evdev_cleanup(evdev);
+ input_free_minor(MINOR(evdev->dev.devt));
input_unregister_handle(handle);
put_device(&evdev->dev);
}
@@ -1078,7 +1045,7 @@ static struct input_handler evdev_handler = {
.events = evdev_events,
.connect = evdev_connect,
.disconnect = evdev_disconnect,
- .fops = &evdev_fops,
+ .legacy_minors = true,
.minor = EVDEV_MINOR_BASE,
.name = "evdev",
.id_table = evdev_ids,