diff options
Diffstat (limited to 'ANDROID_3.4.5/drivers/input/input-polldev.c')
-rw-r--r-- | ANDROID_3.4.5/drivers/input/input-polldev.c | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/ANDROID_3.4.5/drivers/input/input-polldev.c b/ANDROID_3.4.5/drivers/input/input-polldev.c new file mode 100644 index 00000000..7f161d93 --- /dev/null +++ b/ANDROID_3.4.5/drivers/input/input-polldev.c @@ -0,0 +1,253 @@ +/* + * Generic implementation of a polled input device + + * Copyright (c) 2007 Dmitry Torokhov + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/jiffies.h> +#include <linux/slab.h> +#include <linux/mutex.h> +#include <linux/workqueue.h> +#include <linux/module.h> +#include <linux/input-polldev.h> + +MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>"); +MODULE_DESCRIPTION("Generic implementation of a polled input device"); +MODULE_LICENSE("GPL v2"); +MODULE_VERSION("0.1"); + +static void input_polldev_queue_work(struct input_polled_dev *dev) +{ + unsigned long delay; + + delay = msecs_to_jiffies(dev->poll_interval); + if (delay >= HZ) + delay = round_jiffies_relative(delay); + + queue_delayed_work(system_freezable_wq, &dev->work, delay); +} + +static void input_polled_device_work(struct work_struct *work) +{ + struct input_polled_dev *dev = + container_of(work, struct input_polled_dev, work.work); + + dev->poll(dev); + input_polldev_queue_work(dev); +} + +static int input_open_polled_device(struct input_dev *input) +{ + struct input_polled_dev *dev = input_get_drvdata(input); + + if (dev->open) + dev->open(dev); + + /* Only start polling if polling is enabled */ + if (dev->poll_interval > 0) { + dev->poll(dev); + input_polldev_queue_work(dev); + } + + return 0; +} + +static void input_close_polled_device(struct input_dev *input) +{ + struct input_polled_dev *dev = input_get_drvdata(input); + + cancel_delayed_work_sync(&dev->work); + + if (dev->close) + dev->close(dev); +} + +/* SYSFS interface */ + +static ssize_t input_polldev_get_poll(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct input_polled_dev *polldev = dev_get_drvdata(dev); + + return sprintf(buf, "%d\n", polldev->poll_interval); +} + +static ssize_t input_polldev_set_poll(struct device *dev, + struct device_attribute *attr, const char *buf, + size_t count) +{ + struct input_polled_dev *polldev = dev_get_drvdata(dev); + struct input_dev *input = polldev->input; + unsigned int interval; + int err; + + err = kstrtouint(buf, 0, &interval); + if (err) + return err; + + if (interval < polldev->poll_interval_min) + return -EINVAL; + + if (interval > polldev->poll_interval_max) + return -EINVAL; + + mutex_lock(&input->mutex); + + polldev->poll_interval = interval; + + if (input->users) { + cancel_delayed_work_sync(&polldev->work); + if (polldev->poll_interval > 0) + input_polldev_queue_work(polldev); + } + + mutex_unlock(&input->mutex); + + return count; +} + +static DEVICE_ATTR(poll, S_IRUGO | S_IWUSR, input_polldev_get_poll, + input_polldev_set_poll); + + +static ssize_t input_polldev_get_max(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct input_polled_dev *polldev = dev_get_drvdata(dev); + + return sprintf(buf, "%d\n", polldev->poll_interval_max); +} + +static DEVICE_ATTR(max, S_IRUGO, input_polldev_get_max, NULL); + +static ssize_t input_polldev_get_min(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct input_polled_dev *polldev = dev_get_drvdata(dev); + + return sprintf(buf, "%d\n", polldev->poll_interval_min); +} + +static DEVICE_ATTR(min, S_IRUGO, input_polldev_get_min, NULL); + +static struct attribute *sysfs_attrs[] = { + &dev_attr_poll.attr, + &dev_attr_max.attr, + &dev_attr_min.attr, + NULL +}; + +static struct attribute_group input_polldev_attribute_group = { + .attrs = sysfs_attrs +}; + +/** + * input_allocate_polled_device - allocate memory for polled device + * + * The function allocates memory for a polled device and also + * for an input device associated with this polled device. + */ +struct input_polled_dev *input_allocate_polled_device(void) +{ + struct input_polled_dev *dev; + + dev = kzalloc(sizeof(struct input_polled_dev), GFP_KERNEL); + if (!dev) + return NULL; + + dev->input = input_allocate_device(); + if (!dev->input) { + kfree(dev); + return NULL; + } + + return dev; +} +EXPORT_SYMBOL(input_allocate_polled_device); + +/** + * input_free_polled_device - free memory allocated for polled device + * @dev: device to free + * + * The function frees memory allocated for polling device and drops + * reference to the associated input device. + */ +void input_free_polled_device(struct input_polled_dev *dev) +{ + if (dev) { + input_free_device(dev->input); + kfree(dev); + } +} +EXPORT_SYMBOL(input_free_polled_device); + +/** + * input_register_polled_device - register polled device + * @dev: device to register + * + * The function registers previously initialized polled input device + * with input layer. The device should be allocated with call to + * input_allocate_polled_device(). Callers should also set up poll() + * method and set up capabilities (id, name, phys, bits) of the + * corresponding input_dev structure. + */ +int input_register_polled_device(struct input_polled_dev *dev) +{ + struct input_dev *input = dev->input; + int error; + + input_set_drvdata(input, dev); + INIT_DELAYED_WORK(&dev->work, input_polled_device_work); + if (!dev->poll_interval) + dev->poll_interval = 500; + if (!dev->poll_interval_max) + dev->poll_interval_max = dev->poll_interval; + input->open = input_open_polled_device; + input->close = input_close_polled_device; + + error = input_register_device(input); + if (error) + return error; + + error = sysfs_create_group(&input->dev.kobj, + &input_polldev_attribute_group); + if (error) { + input_unregister_device(input); + return error; + } + + /* + * Take extra reference to the underlying input device so + * that it survives call to input_unregister_polled_device() + * and is deleted only after input_free_polled_device() + * has been invoked. This is needed to ease task of freeing + * sparse keymaps. + */ + input_get_device(input); + + return 0; +} +EXPORT_SYMBOL(input_register_polled_device); + +/** + * input_unregister_polled_device - unregister polled device + * @dev: device to unregister + * + * The function unregisters previously registered polled input + * device from input layer. Polling is stopped and device is + * ready to be freed with call to input_free_polled_device(). + */ +void input_unregister_polled_device(struct input_polled_dev *dev) +{ + sysfs_remove_group(&dev->input->dev.kobj, + &input_polldev_attribute_group); + + input_unregister_device(dev->input); +} +EXPORT_SYMBOL(input_unregister_polled_device); |