/* * LED Flash class interface * * Copyright (C) 2015 Samsung Electronics Co., Ltd. * Author: Jacek Anaszewski <j.anaszewski@samsung.com> * * 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/device.h> #include <linux/init.h> #include <linux/led-class-flash.h> #include <linux/leds.h> #include <linux/module.h> #include <linux/slab.h> #include "leds.h" #define has_flash_op(fled_cdev, op) \ (fled_cdev && fled_cdev->ops->op) #define call_flash_op(fled_cdev, op, args...) \ ((has_flash_op(fled_cdev, op)) ? \ (fled_cdev->ops->op(fled_cdev, args)) : \ -EINVAL) static const char * const led_flash_fault_names[] = { "led-over-voltage", "flash-timeout-exceeded", "controller-over-temperature", "controller-short-circuit", "led-power-supply-over-current", "indicator-led-fault", "led-under-voltage", "controller-under-voltage", "led-over-temperature", }; static ssize_t flash_brightness_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { struct led_classdev *led_cdev = dev_get_drvdata(dev); struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev); unsigned long state; ssize_t ret; mutex_lock(&led_cdev->led_access); if (led_sysfs_is_disabled(led_cdev)) { ret = -EBUSY; goto unlock; } ret = kstrtoul(buf, 10, &state); if (ret) goto unlock; ret = led_set_flash_brightness(fled_cdev, state); if (ret < 0) goto unlock; ret = size; unlock: mutex_unlock(&led_cdev->led_access); return ret; } static ssize_t flash_brightness_show(struct device *dev, struct device_attribute *attr, char *buf) { struct led_classdev *led_cdev = dev_get_drvdata(dev); struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev); /* no lock needed for this */ led_update_flash_brightness(fled_cdev); return sprintf(buf, "%u\n", fled_cdev->brightness.val); } static DEVICE_ATTR_RW(flash_brightness); static ssize_t max_flash_brightness_show(struct device *dev, struct device_attribute *attr, char *buf) { struct led_classdev *led_cdev = dev_get_drvdata(dev); struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev); return sprintf(buf, "%u\n", fled_cdev->brightness.max); } static DEVICE_ATTR_RO(max_flash_brightness); static ssize_t flash_strobe_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { struct led_classdev *led_cdev = dev_get_drvdata(dev); struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev); unsigned long state; ssize_t ret = -EINVAL; mutex_lock(&led_cdev->led_access); if (led_sysfs_is_disabled(led_cdev)) { ret = -EBUSY; goto unlock; } ret = kstrtoul(buf, 10, &state); if (ret) goto unlock; if (state < 0 || state > 1) { ret = -EINVAL; goto unlock; } ret = led_set_flash_strobe(fled_cdev, state); if (ret < 0) goto unlock; ret = size; unlock: mutex_unlock(&led_cdev->led_access); return ret; } static ssize_t flash_strobe_show(struct device *dev, struct device_attribute *attr, char *buf) { struct led_classdev *led_cdev = dev_get_drvdata(dev); struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev); bool state; int ret; /* no lock needed for this */ ret = led_get_flash_strobe(fled_cdev, &state); if (ret < 0) return ret; return sprintf(buf, "%u\n", state); } static DEVICE_ATTR_RW(flash_strobe); static ssize_t flash_timeout_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { struct led_classdev *led_cdev = dev_get_drvdata(dev); struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev); unsigned long flash_timeout; ssize_t ret; mutex_lock(&led_cdev->led_access); if (led_sysfs_is_disabled(led_cdev)) { ret = -EBUSY; goto unlock; } ret = kstrtoul(buf, 10, &flash_timeout); if (ret) goto unlock; ret = led_set_flash_timeout(fled_cdev, flash_timeout); if (ret < 0) goto unlock; ret = size; unlock: mutex_unlock(&led_cdev->led_access); return ret; } static ssize_t flash_timeout_show(struct device *dev, struct device_attribute *attr, char *buf) { struct led_classdev *led_cdev = dev_get_drvdata(dev); struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev); return sprintf(buf, "%u\n", fled_cdev->timeout.val); } static DEVICE_ATTR_RW(flash_timeout); static ssize_t max_flash_timeout_show(struct device *dev, struct device_attribute *attr, char *buf) { struct led_classdev *led_cdev = dev_get_drvdata(dev); struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev); return sprintf(buf, "%u\n", fled_cdev->timeout.max); } static DEVICE_ATTR_RO(max_flash_timeout); static ssize_t flash_fault_show(struct device *dev, struct device_attribute *attr, char *buf) { struct led_classdev *led_cdev = dev_get_drvdata(dev); struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev); u32 fault, mask = 0x1; char *pbuf = buf; int i, ret, buf_len; ret = led_get_flash_fault(fled_cdev, &fault); if (ret < 0) return -EINVAL; *buf = '\0'; for (i = 0; i < LED_NUM_FLASH_FAULTS; ++i) { if (fault & mask) { buf_len = sprintf(pbuf, "%s ", led_flash_fault_names[i]); pbuf += buf_len; } mask <<= 1; } return sprintf(buf, "%s\n", buf); } static DEVICE_ATTR_RO(flash_fault); static struct attribute *led_flash_strobe_attrs[] = { &dev_attr_flash_strobe.attr, NULL, }; static struct attribute *led_flash_timeout_attrs[] = { &dev_attr_flash_timeout.attr, &dev_attr_max_flash_timeout.attr, NULL, }; static struct attribute *led_flash_brightness_attrs[] = { &dev_attr_flash_brightness.attr, &dev_attr_max_flash_brightness.attr, NULL, }; static struct attribute *led_flash_fault_attrs[] = { &dev_attr_flash_fault.attr, NULL, }; static const struct attribute_group led_flash_strobe_group = { .attrs = led_flash_strobe_attrs, }; static const struct attribute_group led_flash_timeout_group = { .attrs = led_flash_timeout_attrs, }; static const struct attribute_group led_flash_brightness_group = { .attrs = led_flash_brightness_attrs, }; static const struct attribute_group led_flash_fault_group = { .attrs = led_flash_fault_attrs, }; static void led_flash_resume(struct led_classdev *led_cdev) { struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev); call_flash_op(fled_cdev, flash_brightness_set, fled_cdev->brightness.val); call_flash_op(fled_cdev, timeout_set, fled_cdev->timeout.val); } static void led_flash_init_sysfs_groups(struct led_classdev_flash *fled_cdev) { struct led_classdev *led_cdev = &fled_cdev->led_cdev; const struct led_flash_ops *ops = fled_cdev->ops; const struct attribute_group **flash_groups = fled_cdev->sysfs_groups; int num_sysfs_groups = 0; flash_groups[num_sysfs_groups++] = &led_flash_strobe_group; if (ops->flash_brightness_set) flash_groups[num_sysfs_groups++] = &led_flash_brightness_group; if (ops->timeout_set) flash_groups[num_sysfs_groups++] = &led_flash_timeout_group; if (ops->fault_get) flash_groups[num_sysfs_groups++] = &led_flash_fault_group; led_cdev->groups = flash_groups; } int led_classdev_flash_register(struct device *parent, struct led_classdev_flash *fled_cdev) { struct led_classdev *led_cdev; const struct led_flash_ops *ops; int ret; if (!fled_cdev) return -EINVAL; led_cdev = &fled_cdev->led_cdev; if (led_cdev->flags & LED_DEV_CAP_FLASH) { if (!led_cdev->brightness_set_sync) return -EINVAL; ops = fled_cdev->ops; if (!ops || !ops->strobe_set) return -EINVAL; led_cdev->flash_resume = led_flash_resume; /* Select the sysfs attributes to be created for the device */ led_flash_init_sysfs_groups(fled_cdev); } /* Register led class device */ ret = led_classdev_register(parent, led_cdev); if (ret < 0) return ret; /* Setting a torch brightness needs to have immediate effect */ led_cdev->flags &= ~SET_BRIGHTNESS_ASYNC; led_cdev->flags |= SET_BRIGHTNESS_SYNC; return 0; } EXPORT_SYMBOL_GPL(led_classdev_flash_register); void led_classdev_flash_unregister(struct led_classdev_flash *fled_cdev) { if (!fled_cdev) return; led_classdev_unregister(&fled_cdev->led_cdev); } EXPORT_SYMBOL_GPL(led_classdev_flash_unregister); static void led_clamp_align(struct led_flash_setting *s) { u32 v, offset; v = s->val + s->step / 2; v = clamp(v, s->min, s->max); offset = v - s->min; offset = s->step * (offset / s->step); s->val = s->min + offset; } int led_set_flash_timeout(struct led_classdev_flash *fled_cdev, u32 timeout) { struct led_classdev *led_cdev = &fled_cdev->led_cdev; struct led_flash_setting *s = &fled_cdev->timeout; s->val = timeout; led_clamp_align(s); if (!(led_cdev->flags & LED_SUSPENDED)) return call_flash_op(fled_cdev, timeout_set, s->val); return 0; } EXPORT_SYMBOL_GPL(led_set_flash_timeout); int led_get_flash_fault(struct led_classdev_flash *fled_cdev, u32 *fault) { return call_flash_op(fled_cdev, fault_get, fault); } EXPORT_SYMBOL_GPL(led_get_flash_fault); int led_set_flash_brightness(struct led_classdev_flash *fled_cdev, u32 brightness) { struct led_classdev *led_cdev = &fled_cdev->led_cdev; struct led_flash_setting *s = &fled_cdev->brightness; s->val = brightness; led_clamp_align(s); if (!(led_cdev->flags & LED_SUSPENDED)) return call_flash_op(fled_cdev, flash_brightness_set, s->val); return 0; } EXPORT_SYMBOL_GPL(led_set_flash_brightness); int led_update_flash_brightness(struct led_classdev_flash *fled_cdev) { struct led_flash_setting *s = &fled_cdev->brightness; u32 brightness; if (has_flash_op(fled_cdev, flash_brightness_get)) { int ret = call_flash_op(fled_cdev, flash_brightness_get, &brightness); if (ret < 0) return ret; s->val = brightness; } return 0; } EXPORT_SYMBOL_GPL(led_update_flash_brightness); MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@samsung.com>"); MODULE_DESCRIPTION("LED Flash class interface"); MODULE_LICENSE("GPL v2");