/* * LED support for the input layer * * Copyright 2010-2015 Samuel Thibault <samuel.thibault@ens-lyon.org> * * 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. */ #include <linux/kernel.h> #include <linux/slab.h> #include <linux/module.h> #include <linux/init.h> #include <linux/leds.h> #include <linux/input.h> #if IS_ENABLED(CONFIG_VT) #define VT_TRIGGER(_name) .trigger = _name #else #define VT_TRIGGER(_name) .trigger = NULL #endif static const struct { const char *name; const char *trigger; } input_led_info[LED_CNT] = { [LED_NUML] = { "numlock", VT_TRIGGER("kbd-numlock") }, [LED_CAPSL] = { "capslock", VT_TRIGGER("kbd-capslock") }, [LED_SCROLLL] = { "scrolllock", VT_TRIGGER("kbd-scrolllock") }, [LED_COMPOSE] = { "compose" }, [LED_KANA] = { "kana", VT_TRIGGER("kbd-kanalock") }, [LED_SLEEP] = { "sleep" } , [LED_SUSPEND] = { "suspend" }, [LED_MUTE] = { "mute" }, [LED_MISC] = { "misc" }, [LED_MAIL] = { "mail" }, [LED_CHARGING] = { "charging" }, }; struct input_led { struct led_classdev cdev; struct input_handle *handle; unsigned int code; /* One of LED_* constants */ }; struct input_leds { struct input_handle handle; unsigned int num_leds; struct input_led leds[]; }; static enum led_brightness input_leds_brightness_get(struct led_classdev *cdev) { struct input_led *led = container_of(cdev, struct input_led, cdev); struct input_dev *input = led->handle->dev; return test_bit(led->code, input->led) ? cdev->max_brightness : 0; } static void input_leds_brightness_set(struct led_classdev *cdev, enum led_brightness brightness) { struct input_led *led = container_of(cdev, struct input_led, cdev); input_inject_event(led->handle, EV_LED, led->code, !!brightness); } static void input_leds_event(struct input_handle *handle, unsigned int type, unsigned int code, int value) { } static int input_leds_get_count(struct input_dev *dev) { unsigned int led_code; int count = 0; for_each_set_bit(led_code, dev->ledbit, LED_CNT) if (input_led_info[led_code].name) count++; return count; } static int input_leds_connect(struct input_handler *handler, struct input_dev *dev, const struct input_device_id *id) { struct input_leds *leds; struct input_led *led; unsigned int num_leds; unsigned int led_code; int led_no; int error; num_leds = input_leds_get_count(dev); if (!num_leds) return -ENXIO; leds = kzalloc(sizeof(*leds) + num_leds * sizeof(*leds->leds), GFP_KERNEL); if (!leds) return -ENOMEM; leds->num_leds = num_leds; leds->handle.dev = dev; leds->handle.handler = handler; leds->handle.name = "leds"; leds->handle.private = leds; error = input_register_handle(&leds->handle); if (error) goto err_free_mem; error = input_open_device(&leds->handle); if (error) goto err_unregister_handle; led_no = 0; for_each_set_bit(led_code, dev->ledbit, LED_CNT) { if (!input_led_info[led_code].name) continue; led = &leds->leds[led_no]; led->handle = &leds->handle; led->code = led_code; led->cdev.name = kasprintf(GFP_KERNEL, "%s::%s", dev_name(&dev->dev), input_led_info[led_code].name); if (!led->cdev.name) { error = -ENOMEM; goto err_unregister_leds; } led->cdev.max_brightness = 1; led->cdev.brightness_get = input_leds_brightness_get; led->cdev.brightness_set = input_leds_brightness_set; led->cdev.default_trigger = input_led_info[led_code].trigger; error = led_classdev_register(&dev->dev, &led->cdev); if (error) { dev_err(&dev->dev, "failed to register LED %s: %d\n", led->cdev.name, error); kfree(led->cdev.name); goto err_unregister_leds; } led_no++; } return 0; err_unregister_leds: while (--led_no >= 0) { struct input_led *led = &leds->leds[led_no]; led_classdev_unregister(&led->cdev); kfree(led->cdev.name); } input_close_device(&leds->handle); err_unregister_handle: input_unregister_handle(&leds->handle); err_free_mem: kfree(leds); return error; } static void input_leds_disconnect(struct input_handle *handle) { struct input_leds *leds = handle->private; int i; for (i = 0; i < leds->num_leds; i++) { struct input_led *led = &leds->leds[i]; led_classdev_unregister(&led->cdev); kfree(led->cdev.name); } input_close_device(handle); input_unregister_handle(handle); kfree(leds); } static const struct input_device_id input_leds_ids[] = { { .flags = INPUT_DEVICE_ID_MATCH_EVBIT, .evbit = { BIT_MASK(EV_LED) }, }, { }, }; MODULE_DEVICE_TABLE(input, input_leds_ids); static struct input_handler input_leds_handler = { .event = input_leds_event, .connect = input_leds_connect, .disconnect = input_leds_disconnect, .name = "leds", .id_table = input_leds_ids, }; static int __init input_leds_init(void) { return input_register_handler(&input_leds_handler); } module_init(input_leds_init); static void __exit input_leds_exit(void) { input_unregister_handler(&input_leds_handler); } module_exit(input_leds_exit); MODULE_AUTHOR("Samuel Thibault <samuel.thibault@ens-lyon.org>"); MODULE_AUTHOR("Dmitry Torokhov <dmitry.torokhov@gmail.com>"); MODULE_DESCRIPTION("Input -> LEDs Bridge"); MODULE_LICENSE("GPL v2");