#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,
static void __input_release_device(struct input_handle *handle)
{
struct input_dev *dev = handle->dev;
+ struct input_handle *grabber;
- if (dev->grab == handle) {
+ grabber = rcu_dereference_protected(dev->grab,
+ lockdep_is_held(&dev->mutex));
+ if (grabber == handle) {
rcu_assign_pointer(dev->grab, NULL);
/* Make sure input_pass_event() notices that grab is gone */
synchronize_rcu();
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');
/**
* input_allocate_device - allocate memory for new input device
*
- * Returns prepared struct input_dev or NULL.
+ * Returns prepared struct input_dev or %NULL.
*
* NOTE: Use input_free_device() to free devices that have not been
* registered; input_unregister_device() should be used for already
}
EXPORT_SYMBOL(input_allocate_device);
+struct input_devres {
+ struct input_dev *input;
+};
+
+static int devm_input_device_match(struct device *dev, void *res, void *data)
+{
+ struct input_devres *devres = res;
+
+ return devres->input == data;
+}
+
+static void devm_input_device_release(struct device *dev, void *res)
+{
+ struct input_devres *devres = res;
+ struct input_dev *input = devres->input;
+
+ dev_dbg(dev, "%s: dropping reference to %s\n",
+ __func__, dev_name(&input->dev));
+ input_put_device(input);
+}
+
+/**
+ * devm_input_allocate_device - allocate managed input device
+ * @dev: device owning the input device being created
+ *
+ * Returns prepared struct input_dev or %NULL.
+ *
+ * Managed input devices do not need to be explicitly unregistered or
+ * freed as it will be done automatically when owner device unbinds from
+ * its driver (or binding fails). Once managed input device is allocated,
+ * it is ready to be set up and registered in the same fashion as regular
+ * input device. There are no special devm_input_device_[un]register()
+ * variants, regular ones work with both managed and unmanaged devices,
+ * should you need them. In most cases however, managed input device need
+ * not be explicitly unregistered or freed.
+ *
+ * NOTE: the owner device is set up as parent of input device and users
+ * should not override it.
+ */
+struct input_dev *devm_input_allocate_device(struct device *dev)
+{
+ struct input_dev *input;
+ struct input_devres *devres;
+
+ devres = devres_alloc(devm_input_device_release,
+ sizeof(struct input_devres), GFP_KERNEL);
+ if (!devres)
+ return NULL;
+
+ input = input_allocate_device();
+ if (!input) {
+ devres_free(devres);
+ return NULL;
+ }
+
+ input->dev.parent = dev;
+ input->devres_managed = true;
+
+ devres->input = input;
+ devres_add(dev, devres);
+
+ return input;
+}
+EXPORT_SYMBOL(devm_input_allocate_device);
+
/**
* input_free_device - free memory occupied by input_dev structure
* @dev: input device to free
*/
void input_free_device(struct input_dev *dev)
{
- if (dev)
+ if (dev) {
+ if (dev->devres_managed)
+ WARN_ON(devres_destroy(dev->dev.parent,
+ devm_input_device_release,
+ devm_input_device_match,
+ dev));
input_put_device(dev);
+ }
}
EXPORT_SYMBOL(input_free_device);
INPUT_CLEANSE_BITMASK(dev, SW, sw);
}
+static void __input_unregister_device(struct input_dev *dev)
+{
+ struct input_handle *handle, *next;
+
+ input_disconnect_device(dev);
+
+ mutex_lock(&input_mutex);
+
+ list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
+ handle->handler->disconnect(handle);
+ WARN_ON(!list_empty(&dev->h_list));
+
+ del_timer_sync(&dev->timer);
+ list_del_init(&dev->node);
+
+ input_wakeup_procfs_readers();
+
+ mutex_unlock(&input_mutex);
+
+ device_del(&dev->dev);
+}
+
+static void devm_input_device_unregister(struct device *dev, void *res)
+{
+ struct input_devres *devres = res;
+ struct input_dev *input = devres->input;
+
+ dev_dbg(dev, "%s: unregistering device %s\n",
+ __func__, dev_name(&input->dev));
+ __input_unregister_device(input);
+}
+
/**
* input_register_device - register device with input core
* @dev: device to be registered
* Once device has been successfully registered it can be unregistered
* with input_unregister_device(); input_free_device() should not be
* called in this case.
+ *
+ * Note that this function is also used to register managed input devices
+ * (ones allocated with devm_input_allocate_device()). Such managed input
+ * devices need not be explicitly unregistered or freed, their tear down
+ * is controlled by the devres infrastructure. It is also worth noting
+ * that tear down of managed input devices is internally a 2-step process:
+ * registered managed input device is first unregistered, but stays in
+ * memory and can still handle input_event() calls (although events will
+ * not be delivered anywhere). The freeing of managed input device will
+ * happen later, when devres stack is unwound to the point where device
+ * allocation was made.
*/
int input_register_device(struct input_dev *dev)
{
static atomic_t input_no = ATOMIC_INIT(0);
+ struct input_devres *devres = NULL;
struct input_handler *handler;
unsigned int packet_size;
const char *path;
int error;
+ if (dev->devres_managed) {
+ devres = devres_alloc(devm_input_device_unregister,
+ sizeof(struct input_devres), GFP_KERNEL);
+ if (!devres)
+ return -ENOMEM;
+
+ devres->input = dev;
+ }
+
/* Every input device generates EV_SYN/SYN_REPORT events. */
__set_bit(EV_SYN, dev->evbit);
dev->max_vals = max(dev->hint_events_per_packet, packet_size) + 2;
dev->vals = kcalloc(dev->max_vals, sizeof(*dev->vals), GFP_KERNEL);
- if (!dev->vals)
- return -ENOMEM;
+ if (!dev->vals) {
+ error = -ENOMEM;
+ goto err_devres_free;
+ }
/*
* If delay and period are pre-set by the driver, then autorepeating
error = device_add(&dev->dev);
if (error)
- return error;
+ goto err_free_vals;
path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
pr_info("%s as %s\n",
kfree(path);
error = mutex_lock_interruptible(&input_mutex);
- if (error) {
- device_del(&dev->dev);
- return error;
- }
+ if (error)
+ goto err_device_del;
list_add_tail(&dev->node, &input_dev_list);
mutex_unlock(&input_mutex);
+ if (dev->devres_managed) {
+ dev_dbg(dev->dev.parent, "%s: registering %s with devres.\n",
+ __func__, dev_name(&dev->dev));
+ devres_add(dev->dev.parent, devres);
+ }
return 0;
+
+err_device_del:
+ device_del(&dev->dev);
+err_free_vals:
+ kfree(dev->vals);
+ dev->vals = NULL;
+err_devres_free:
+ devres_free(devres);
+ return error;
}
EXPORT_SYMBOL(input_register_device);
*/
void input_unregister_device(struct input_dev *dev)
{
- struct input_handle *handle, *next;
-
- input_disconnect_device(dev);
-
- mutex_lock(&input_mutex);
-
- list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
- handle->handler->disconnect(handle);
- WARN_ON(!list_empty(&dev->h_list));
-
- del_timer_sync(&dev->timer);
- list_del_init(&dev->node);
-
- input_wakeup_procfs_readers();
-
- mutex_unlock(&input_mutex);
-
- device_unregister(&dev->dev);
+ if (dev->devres_managed) {
+ WARN_ON(devres_destroy(dev->dev.parent,
+ devm_input_device_unregister,
+ devm_input_device_match,
+ dev));
+ __input_unregister_device(dev);
+ /*
+ * We do not do input_put_device() here because it will be done
+ * when 2nd devres fires up.
+ */
+ } else {
+ __input_unregister_device(dev);
+ input_put_device(dev);
+ }
}
EXPORT_SYMBOL(input_unregister_device);
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