/* * LP5521/LP5523/LP55231 Common Driver * * Copyright 2012 Texas Instruments * * Author: Milo(Woogyom) Kim * * 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. * * Derived from leds-lp5521.c, leds-lp5523.c */ #include #include #include #include #include #include "leds-lp55xx-common.h" static struct lp55xx_led *cdev_to_lp55xx_led(struct led_classdev *cdev) { return container_of(cdev, struct lp55xx_led, cdev); } static struct lp55xx_led *dev_to_lp55xx_led(struct device *dev) { return cdev_to_lp55xx_led(dev_get_drvdata(dev)); } static void lp55xx_reset_device(struct lp55xx_chip *chip) { struct lp55xx_device_config *cfg = chip->cfg; u8 addr = cfg->reset.addr; u8 val = cfg->reset.val; /* no error checking here because no ACK from the device after reset */ lp55xx_write(chip, addr, val); } static int lp55xx_detect_device(struct lp55xx_chip *chip) { struct lp55xx_device_config *cfg = chip->cfg; u8 addr = cfg->enable.addr; u8 val = cfg->enable.val; int ret; ret = lp55xx_write(chip, addr, val); if (ret) return ret; usleep_range(1000, 2000); ret = lp55xx_read(chip, addr, &val); if (ret) return ret; if (val != cfg->enable.val) return -ENODEV; return 0; } static int lp55xx_post_init_device(struct lp55xx_chip *chip) { struct lp55xx_device_config *cfg = chip->cfg; if (!cfg->post_init_device) return 0; return cfg->post_init_device(chip); } static ssize_t lp55xx_show_current(struct device *dev, struct device_attribute *attr, char *buf) { struct lp55xx_led *led = dev_to_lp55xx_led(dev); return sprintf(buf, "%d\n", led->led_current); } static ssize_t lp55xx_store_current(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { struct lp55xx_led *led = dev_to_lp55xx_led(dev); struct lp55xx_chip *chip = led->chip; unsigned long curr; if (kstrtoul(buf, 0, &curr)) return -EINVAL; if (curr > led->max_current) return -EINVAL; if (!chip->cfg->set_led_current) return len; mutex_lock(&chip->lock); chip->cfg->set_led_current(led, (u8)curr); mutex_unlock(&chip->lock); return len; } static ssize_t lp55xx_show_max_current(struct device *dev, struct device_attribute *attr, char *buf) { struct lp55xx_led *led = dev_to_lp55xx_led(dev); return sprintf(buf, "%d\n", led->max_current); } static DEVICE_ATTR(led_current, S_IRUGO | S_IWUSR, lp55xx_show_current, lp55xx_store_current); static DEVICE_ATTR(max_current, S_IRUGO , lp55xx_show_max_current, NULL); static struct attribute *lp55xx_led_attributes[] = { &dev_attr_led_current.attr, &dev_attr_max_current.attr, NULL, }; static struct attribute_group lp55xx_led_attr_group = { .attrs = lp55xx_led_attributes }; static void lp55xx_set_brightness(struct led_classdev *cdev, enum led_brightness brightness) { struct lp55xx_led *led = cdev_to_lp55xx_led(cdev); led->brightness = (u8)brightness; schedule_work(&led->brightness_work); } static int lp55xx_init_led(struct lp55xx_led *led, struct lp55xx_chip *chip, int chan) { struct lp55xx_platform_data *pdata = chip->pdata; struct lp55xx_device_config *cfg = chip->cfg; struct device *dev = &chip->cl->dev; char name[32]; int ret; int max_channel = cfg->max_channel; if (chan >= max_channel) { dev_err(dev, "invalid channel: %d / %d\n", chan, max_channel); return -EINVAL; } if (pdata->led_config[chan].led_current == 0) return 0; led->led_current = pdata->led_config[chan].led_current; led->max_current = pdata->led_config[chan].max_current; led->chan_nr = pdata->led_config[chan].chan_nr; if (led->chan_nr >= max_channel) { dev_err(dev, "Use channel numbers between 0 and %d\n", max_channel - 1); return -EINVAL; } led->cdev.brightness_set = lp55xx_set_brightness; if (pdata->led_config[chan].name) { led->cdev.name = pdata->led_config[chan].name; } else { snprintf(name, sizeof(name), "%s:channel%d", pdata->label ? : chip->cl->name, chan); led->cdev.name = name; } /* * register led class device for each channel and * add device attributes */ ret = led_classdev_register(dev, &led->cdev); if (ret) { dev_err(dev, "led register err: %d\n", ret); return ret; } ret = sysfs_create_group(&led->cdev.dev->kobj, &lp55xx_led_attr_group); if (ret) { dev_err(dev, "led sysfs err: %d\n", ret); led_classdev_unregister(&led->cdev); return ret; } return 0; } int lp55xx_write(struct lp55xx_chip *chip, u8 reg, u8 val) { return i2c_smbus_write_byte_data(chip->cl, reg, val); } EXPORT_SYMBOL_GPL(lp55xx_write); int lp55xx_read(struct lp55xx_chip *chip, u8 reg, u8 *val) { s32 ret; ret = i2c_smbus_read_byte_data(chip->cl, reg); if (ret < 0) return ret; *val = ret; return 0; } EXPORT_SYMBOL_GPL(lp55xx_read); int lp55xx_update_bits(struct lp55xx_chip *chip, u8 reg, u8 mask, u8 val) { int ret; u8 tmp; ret = lp55xx_read(chip, reg, &tmp); if (ret) return ret; tmp &= ~mask; tmp |= val & mask; return lp55xx_write(chip, reg, tmp); } EXPORT_SYMBOL_GPL(lp55xx_update_bits); int lp55xx_init_device(struct lp55xx_chip *chip) { struct lp55xx_platform_data *pdata; struct lp55xx_device_config *cfg; struct device *dev = &chip->cl->dev; int ret = 0; WARN_ON(!chip); pdata = chip->pdata; cfg = chip->cfg; if (!pdata || !cfg) return -EINVAL; if (pdata->setup_resources) { ret = pdata->setup_resources(); if (ret < 0) { dev_err(dev, "setup resoure err: %d\n", ret); goto err; } } if (pdata->enable) { pdata->enable(0); usleep_range(1000, 2000); /* Keep enable down at least 1ms */ pdata->enable(1); usleep_range(1000, 2000); /* 500us abs min. */ } lp55xx_reset_device(chip); /* * Exact value is not available. 10 - 20ms * appears to be enough for reset. */ usleep_range(10000, 20000); ret = lp55xx_detect_device(chip); if (ret) { dev_err(dev, "device detection err: %d\n", ret); goto err; } /* chip specific initialization */ ret = lp55xx_post_init_device(chip); if (ret) { dev_err(dev, "post init device err: %d\n", ret); goto err_post_init; } return 0; err_post_init: lp55xx_deinit_device(chip); err: return ret; } EXPORT_SYMBOL_GPL(lp55xx_init_device); void lp55xx_deinit_device(struct lp55xx_chip *chip) { struct lp55xx_platform_data *pdata = chip->pdata; if (pdata->enable) pdata->enable(0); if (pdata->release_resources) pdata->release_resources(); } EXPORT_SYMBOL_GPL(lp55xx_deinit_device); int lp55xx_register_leds(struct lp55xx_led *led, struct lp55xx_chip *chip) { struct lp55xx_platform_data *pdata = chip->pdata; struct lp55xx_device_config *cfg = chip->cfg; int num_channels = pdata->num_channels; struct lp55xx_led *each; u8 led_current; int ret; int i; if (!cfg->brightness_work_fn) { dev_err(&chip->cl->dev, "empty brightness configuration\n"); return -EINVAL; } for (i = 0; i < num_channels; i++) { /* do not initialize channels that are not connected */ if (pdata->led_config[i].led_current == 0) continue; led_current = pdata->led_config[i].led_current; each = led + i; ret = lp55xx_init_led(each, chip, i); if (ret) goto err_init_led; INIT_WORK(&each->brightness_work, cfg->brightness_work_fn); chip->num_leds++; each->chip = chip; /* setting led current at each channel */ if (cfg->set_led_current) cfg->set_led_current(each, led_current); } return 0; err_init_led: lp55xx_unregister_leds(led, chip); return ret; } EXPORT_SYMBOL_GPL(lp55xx_register_leds); void lp55xx_unregister_leds(struct lp55xx_led *led, struct lp55xx_chip *chip) { int i; struct lp55xx_led *each; struct kobject *kobj; for (i = 0; i < chip->num_leds; i++) { each = led + i; kobj = &led->cdev.dev->kobj; sysfs_remove_group(kobj, &lp55xx_led_attr_group); led_classdev_unregister(&each->cdev); flush_work(&each->brightness_work); } } EXPORT_SYMBOL_GPL(lp55xx_unregister_leds); MODULE_AUTHOR("Milo Kim "); MODULE_DESCRIPTION("LP55xx Common Driver"); MODULE_LICENSE("GPL");