/* * LP5521/LP5523/LP55231/LP5562 Common Driver * * Copyright 2012 Texas Instruments * * Author: Milo(Woogyom) Kim <milo.kim@ti.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. * * Derived from leds-lp5521.c, leds-lp5523.c */ #include <linux/clk.h> #include <linux/delay.h> #include <linux/firmware.h> #include <linux/i2c.h> #include <linux/leds.h> #include <linux/module.h> #include <linux/platform_data/leds-lp55xx.h> #include <linux/slab.h> #include <linux/gpio.h> #include <linux/of_gpio.h> #include "leds-lp55xx-common.h" /* External clock rate */ #define LP55XX_CLK_32K 32768 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 scnprintf(buf, PAGE_SIZE, "%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 scnprintf(buf, PAGE_SIZE, "%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; led->cdev.default_trigger = pdata->led_config[chan].default_trigger; 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; } static void lp55xx_firmware_loaded(const struct firmware *fw, void *context) { struct lp55xx_chip *chip = context; struct device *dev = &chip->cl->dev; enum lp55xx_engine_index idx = chip->engine_idx; if (!fw) { dev_err(dev, "firmware request failed\n"); goto out; } /* handling firmware data is chip dependent */ mutex_lock(&chip->lock); chip->engines[idx - 1].mode = LP55XX_ENGINE_LOAD; chip->fw = fw; if (chip->cfg->firmware_cb) chip->cfg->firmware_cb(chip); mutex_unlock(&chip->lock); out: /* firmware should be released for other channel use */ release_firmware(chip->fw); } static int lp55xx_request_firmware(struct lp55xx_chip *chip) { const char *name = chip->cl->name; struct device *dev = &chip->cl->dev; return request_firmware_nowait(THIS_MODULE, true, name, dev, GFP_KERNEL, chip, lp55xx_firmware_loaded); } static ssize_t lp55xx_show_engine_select(struct device *dev, struct device_attribute *attr, char *buf) { struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); struct lp55xx_chip *chip = led->chip; return sprintf(buf, "%d\n", chip->engine_idx); } static ssize_t lp55xx_store_engine_select(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); struct lp55xx_chip *chip = led->chip; unsigned long val; int ret; if (kstrtoul(buf, 0, &val)) return -EINVAL; /* select the engine to be run */ switch (val) { case LP55XX_ENGINE_1: case LP55XX_ENGINE_2: case LP55XX_ENGINE_3: mutex_lock(&chip->lock); chip->engine_idx = val; ret = lp55xx_request_firmware(chip); mutex_unlock(&chip->lock); break; default: dev_err(dev, "%lu: invalid engine index. (1, 2, 3)\n", val); return -EINVAL; } if (ret) { dev_err(dev, "request firmware err: %d\n", ret); return ret; } return len; } static inline void lp55xx_run_engine(struct lp55xx_chip *chip, bool start) { if (chip->cfg->run_engine) chip->cfg->run_engine(chip, start); } static ssize_t lp55xx_store_engine_run(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); struct lp55xx_chip *chip = led->chip; unsigned long val; if (kstrtoul(buf, 0, &val)) return -EINVAL; /* run or stop the selected engine */ if (val <= 0) { lp55xx_run_engine(chip, false); return len; } mutex_lock(&chip->lock); lp55xx_run_engine(chip, true); mutex_unlock(&chip->lock); return len; } static DEVICE_ATTR(select_engine, S_IRUGO | S_IWUSR, lp55xx_show_engine_select, lp55xx_store_engine_select); static DEVICE_ATTR(run_engine, S_IWUSR, NULL, lp55xx_store_engine_run); static struct attribute *lp55xx_engine_attributes[] = { &dev_attr_select_engine.attr, &dev_attr_run_engine.attr, NULL, }; static const struct attribute_group lp55xx_engine_attr_group = { .attrs = lp55xx_engine_attributes, }; 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); bool lp55xx_is_extclk_used(struct lp55xx_chip *chip) { struct clk *clk; int err; clk = devm_clk_get(&chip->cl->dev, "32k_clk"); if (IS_ERR(clk)) goto use_internal_clk; err = clk_prepare_enable(clk); if (err) goto use_internal_clk; if (clk_get_rate(clk) != LP55XX_CLK_32K) { clk_disable_unprepare(clk); goto use_internal_clk; } dev_info(&chip->cl->dev, "%dHz external clock used\n", LP55XX_CLK_32K); chip->clk = clk; return true; use_internal_clk: dev_info(&chip->cl->dev, "internal clock used\n"); return false; } EXPORT_SYMBOL_GPL(lp55xx_is_extclk_used); 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 (gpio_is_valid(pdata->enable_gpio)) { ret = devm_gpio_request_one(dev, pdata->enable_gpio, GPIOF_DIR_OUT, "lp5523_enable"); if (ret < 0) { dev_err(dev, "could not acquire enable gpio (err=%d)\n", ret); goto err; } gpio_set_value(pdata->enable_gpio, 0); usleep_range(1000, 2000); /* Keep enable down at least 1ms */ gpio_set_value(pdata->enable_gpio, 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 (chip->clk) clk_disable_unprepare(chip->clk); if (gpio_is_valid(pdata->enable_gpio)) gpio_set_value(pdata->enable_gpio, 0); } 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; for (i = 0; i < chip->num_leds; i++) { each = led + i; sysfs_remove_group(&each->cdev.dev->kobj, &lp55xx_led_attr_group); led_classdev_unregister(&each->cdev); flush_work(&each->brightness_work); } } EXPORT_SYMBOL_GPL(lp55xx_unregister_leds); int lp55xx_register_sysfs(struct lp55xx_chip *chip) { struct device *dev = &chip->cl->dev; struct lp55xx_device_config *cfg = chip->cfg; int ret; if (!cfg->run_engine || !cfg->firmware_cb) goto dev_specific_attrs; ret = sysfs_create_group(&dev->kobj, &lp55xx_engine_attr_group); if (ret) return ret; dev_specific_attrs: return cfg->dev_attr_group ? sysfs_create_group(&dev->kobj, cfg->dev_attr_group) : 0; } EXPORT_SYMBOL_GPL(lp55xx_register_sysfs); void lp55xx_unregister_sysfs(struct lp55xx_chip *chip) { struct device *dev = &chip->cl->dev; struct lp55xx_device_config *cfg = chip->cfg; if (cfg->dev_attr_group) sysfs_remove_group(&dev->kobj, cfg->dev_attr_group); sysfs_remove_group(&dev->kobj, &lp55xx_engine_attr_group); } EXPORT_SYMBOL_GPL(lp55xx_unregister_sysfs); int lp55xx_of_populate_pdata(struct device *dev, struct device_node *np) { struct device_node *child; struct lp55xx_platform_data *pdata; struct lp55xx_led_config *cfg; int num_channels; int i = 0; pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); if (!pdata) return -ENOMEM; num_channels = of_get_child_count(np); if (num_channels == 0) { dev_err(dev, "no LED channels\n"); return -EINVAL; } cfg = devm_kzalloc(dev, sizeof(*cfg) * num_channels, GFP_KERNEL); if (!cfg) return -ENOMEM; pdata->led_config = &cfg[0]; pdata->num_channels = num_channels; for_each_child_of_node(np, child) { cfg[i].chan_nr = i; of_property_read_string(child, "chan-name", &cfg[i].name); of_property_read_u8(child, "led-cur", &cfg[i].led_current); of_property_read_u8(child, "max-cur", &cfg[i].max_current); cfg[i].default_trigger = of_get_property(child, "linux,default-trigger", NULL); i++; } of_property_read_string(np, "label", &pdata->label); of_property_read_u8(np, "clock-mode", &pdata->clock_mode); pdata->enable_gpio = of_get_named_gpio(np, "enable-gpio", 0); /* LP8501 specific */ of_property_read_u8(np, "pwr-sel", (u8 *)&pdata->pwr_sel); dev->platform_data = pdata; return 0; } EXPORT_SYMBOL_GPL(lp55xx_of_populate_pdata); MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>"); MODULE_DESCRIPTION("LP55xx Common Driver"); MODULE_LICENSE("GPL");