2 * LP5521/LP5523/LP55231/LP5562 Common Driver
4 * Copyright 2012 Texas Instruments
6 * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
12 * Derived from leds-lp5521.c, leds-lp5523.c
15 #include <linux/clk.h>
16 #include <linux/delay.h>
17 #include <linux/firmware.h>
18 #include <linux/i2c.h>
19 #include <linux/leds.h>
20 #include <linux/module.h>
21 #include <linux/platform_data/leds-lp55xx.h>
22 #include <linux/slab.h>
24 #include "leds-lp55xx-common.h"
26 /* External clock rate */
27 #define LP55XX_CLK_32K 32768
29 static struct lp55xx_led *cdev_to_lp55xx_led(struct led_classdev *cdev)
31 return container_of(cdev, struct lp55xx_led, cdev);
34 static struct lp55xx_led *dev_to_lp55xx_led(struct device *dev)
36 return cdev_to_lp55xx_led(dev_get_drvdata(dev));
39 static void lp55xx_reset_device(struct lp55xx_chip *chip)
41 struct lp55xx_device_config *cfg = chip->cfg;
42 u8 addr = cfg->reset.addr;
43 u8 val = cfg->reset.val;
45 /* no error checking here because no ACK from the device after reset */
46 lp55xx_write(chip, addr, val);
49 static int lp55xx_detect_device(struct lp55xx_chip *chip)
51 struct lp55xx_device_config *cfg = chip->cfg;
52 u8 addr = cfg->enable.addr;
53 u8 val = cfg->enable.val;
56 ret = lp55xx_write(chip, addr, val);
60 usleep_range(1000, 2000);
62 ret = lp55xx_read(chip, addr, &val);
66 if (val != cfg->enable.val)
72 static int lp55xx_post_init_device(struct lp55xx_chip *chip)
74 struct lp55xx_device_config *cfg = chip->cfg;
76 if (!cfg->post_init_device)
79 return cfg->post_init_device(chip);
82 static ssize_t lp55xx_show_current(struct device *dev,
83 struct device_attribute *attr,
86 struct lp55xx_led *led = dev_to_lp55xx_led(dev);
88 return scnprintf(buf, PAGE_SIZE, "%d\n", led->led_current);
91 static ssize_t lp55xx_store_current(struct device *dev,
92 struct device_attribute *attr,
93 const char *buf, size_t len)
95 struct lp55xx_led *led = dev_to_lp55xx_led(dev);
96 struct lp55xx_chip *chip = led->chip;
99 if (kstrtoul(buf, 0, &curr))
102 if (curr > led->max_current)
105 if (!chip->cfg->set_led_current)
108 mutex_lock(&chip->lock);
109 chip->cfg->set_led_current(led, (u8)curr);
110 mutex_unlock(&chip->lock);
115 static ssize_t lp55xx_show_max_current(struct device *dev,
116 struct device_attribute *attr,
119 struct lp55xx_led *led = dev_to_lp55xx_led(dev);
121 return scnprintf(buf, PAGE_SIZE, "%d\n", led->max_current);
124 static DEVICE_ATTR(led_current, S_IRUGO | S_IWUSR, lp55xx_show_current,
125 lp55xx_store_current);
126 static DEVICE_ATTR(max_current, S_IRUGO , lp55xx_show_max_current, NULL);
128 static struct attribute *lp55xx_led_attributes[] = {
129 &dev_attr_led_current.attr,
130 &dev_attr_max_current.attr,
134 static struct attribute_group lp55xx_led_attr_group = {
135 .attrs = lp55xx_led_attributes
138 static void lp55xx_set_brightness(struct led_classdev *cdev,
139 enum led_brightness brightness)
141 struct lp55xx_led *led = cdev_to_lp55xx_led(cdev);
143 led->brightness = (u8)brightness;
144 schedule_work(&led->brightness_work);
147 static int lp55xx_init_led(struct lp55xx_led *led,
148 struct lp55xx_chip *chip, int chan)
150 struct lp55xx_platform_data *pdata = chip->pdata;
151 struct lp55xx_device_config *cfg = chip->cfg;
152 struct device *dev = &chip->cl->dev;
155 int max_channel = cfg->max_channel;
157 if (chan >= max_channel) {
158 dev_err(dev, "invalid channel: %d / %d\n", chan, max_channel);
162 if (pdata->led_config[chan].led_current == 0)
165 led->led_current = pdata->led_config[chan].led_current;
166 led->max_current = pdata->led_config[chan].max_current;
167 led->chan_nr = pdata->led_config[chan].chan_nr;
168 led->cdev.default_trigger = pdata->led_config[chan].default_trigger;
170 if (led->chan_nr >= max_channel) {
171 dev_err(dev, "Use channel numbers between 0 and %d\n",
176 led->cdev.brightness_set = lp55xx_set_brightness;
178 if (pdata->led_config[chan].name) {
179 led->cdev.name = pdata->led_config[chan].name;
181 snprintf(name, sizeof(name), "%s:channel%d",
182 pdata->label ? : chip->cl->name, chan);
183 led->cdev.name = name;
187 * register led class device for each channel and
188 * add device attributes
191 ret = led_classdev_register(dev, &led->cdev);
193 dev_err(dev, "led register err: %d\n", ret);
197 ret = sysfs_create_group(&led->cdev.dev->kobj, &lp55xx_led_attr_group);
199 dev_err(dev, "led sysfs err: %d\n", ret);
200 led_classdev_unregister(&led->cdev);
207 static void lp55xx_firmware_loaded(const struct firmware *fw, void *context)
209 struct lp55xx_chip *chip = context;
210 struct device *dev = &chip->cl->dev;
213 dev_err(dev, "firmware request failed\n");
217 /* handling firmware data is chip dependent */
218 mutex_lock(&chip->lock);
221 if (chip->cfg->firmware_cb)
222 chip->cfg->firmware_cb(chip);
224 mutex_unlock(&chip->lock);
227 /* firmware should be released for other channel use */
228 release_firmware(chip->fw);
231 static int lp55xx_request_firmware(struct lp55xx_chip *chip)
233 const char *name = chip->cl->name;
234 struct device *dev = &chip->cl->dev;
236 return request_firmware_nowait(THIS_MODULE, true, name, dev,
237 GFP_KERNEL, chip, lp55xx_firmware_loaded);
240 static ssize_t lp55xx_show_engine_select(struct device *dev,
241 struct device_attribute *attr,
244 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
245 struct lp55xx_chip *chip = led->chip;
247 return sprintf(buf, "%d\n", chip->engine_idx);
250 static ssize_t lp55xx_store_engine_select(struct device *dev,
251 struct device_attribute *attr,
252 const char *buf, size_t len)
254 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
255 struct lp55xx_chip *chip = led->chip;
259 if (kstrtoul(buf, 0, &val))
262 /* select the engine to be run */
265 case LP55XX_ENGINE_1:
266 case LP55XX_ENGINE_2:
267 case LP55XX_ENGINE_3:
268 mutex_lock(&chip->lock);
269 chip->engine_idx = val;
270 ret = lp55xx_request_firmware(chip);
271 mutex_unlock(&chip->lock);
274 dev_err(dev, "%lu: invalid engine index. (1, 2, 3)\n", val);
279 dev_err(dev, "request firmware err: %d\n", ret);
286 static inline void lp55xx_run_engine(struct lp55xx_chip *chip, bool start)
288 if (chip->cfg->run_engine)
289 chip->cfg->run_engine(chip, start);
292 static ssize_t lp55xx_store_engine_run(struct device *dev,
293 struct device_attribute *attr,
294 const char *buf, size_t len)
296 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
297 struct lp55xx_chip *chip = led->chip;
300 if (kstrtoul(buf, 0, &val))
303 /* run or stop the selected engine */
306 lp55xx_run_engine(chip, false);
310 mutex_lock(&chip->lock);
311 lp55xx_run_engine(chip, true);
312 mutex_unlock(&chip->lock);
317 static DEVICE_ATTR(select_engine, S_IRUGO | S_IWUSR,
318 lp55xx_show_engine_select, lp55xx_store_engine_select);
319 static DEVICE_ATTR(run_engine, S_IWUSR, NULL, lp55xx_store_engine_run);
321 static struct attribute *lp55xx_engine_attributes[] = {
322 &dev_attr_select_engine.attr,
323 &dev_attr_run_engine.attr,
327 static const struct attribute_group lp55xx_engine_attr_group = {
328 .attrs = lp55xx_engine_attributes,
331 int lp55xx_write(struct lp55xx_chip *chip, u8 reg, u8 val)
333 return i2c_smbus_write_byte_data(chip->cl, reg, val);
335 EXPORT_SYMBOL_GPL(lp55xx_write);
337 int lp55xx_read(struct lp55xx_chip *chip, u8 reg, u8 *val)
341 ret = i2c_smbus_read_byte_data(chip->cl, reg);
348 EXPORT_SYMBOL_GPL(lp55xx_read);
350 int lp55xx_update_bits(struct lp55xx_chip *chip, u8 reg, u8 mask, u8 val)
355 ret = lp55xx_read(chip, reg, &tmp);
362 return lp55xx_write(chip, reg, tmp);
364 EXPORT_SYMBOL_GPL(lp55xx_update_bits);
366 bool lp55xx_is_extclk_used(struct lp55xx_chip *chip)
371 clk = devm_clk_get(&chip->cl->dev, "32k_clk");
373 goto use_internal_clk;
375 err = clk_prepare_enable(clk);
377 goto use_internal_clk;
379 if (clk_get_rate(clk) != LP55XX_CLK_32K) {
380 clk_disable_unprepare(clk);
381 goto use_internal_clk;
384 dev_info(&chip->cl->dev, "%dHz external clock used\n", LP55XX_CLK_32K);
390 dev_info(&chip->cl->dev, "internal clock used\n");
393 EXPORT_SYMBOL_GPL(lp55xx_is_extclk_used);
395 int lp55xx_init_device(struct lp55xx_chip *chip)
397 struct lp55xx_platform_data *pdata;
398 struct lp55xx_device_config *cfg;
399 struct device *dev = &chip->cl->dev;
410 if (pdata->setup_resources) {
411 ret = pdata->setup_resources();
413 dev_err(dev, "setup resoure err: %d\n", ret);
420 usleep_range(1000, 2000); /* Keep enable down at least 1ms */
422 usleep_range(1000, 2000); /* 500us abs min. */
425 lp55xx_reset_device(chip);
428 * Exact value is not available. 10 - 20ms
429 * appears to be enough for reset.
431 usleep_range(10000, 20000);
433 ret = lp55xx_detect_device(chip);
435 dev_err(dev, "device detection err: %d\n", ret);
439 /* chip specific initialization */
440 ret = lp55xx_post_init_device(chip);
442 dev_err(dev, "post init device err: %d\n", ret);
449 lp55xx_deinit_device(chip);
453 EXPORT_SYMBOL_GPL(lp55xx_init_device);
455 void lp55xx_deinit_device(struct lp55xx_chip *chip)
457 struct lp55xx_platform_data *pdata = chip->pdata;
460 clk_disable_unprepare(chip->clk);
465 if (pdata->release_resources)
466 pdata->release_resources();
468 EXPORT_SYMBOL_GPL(lp55xx_deinit_device);
470 int lp55xx_register_leds(struct lp55xx_led *led, struct lp55xx_chip *chip)
472 struct lp55xx_platform_data *pdata = chip->pdata;
473 struct lp55xx_device_config *cfg = chip->cfg;
474 int num_channels = pdata->num_channels;
475 struct lp55xx_led *each;
480 if (!cfg->brightness_work_fn) {
481 dev_err(&chip->cl->dev, "empty brightness configuration\n");
485 for (i = 0; i < num_channels; i++) {
487 /* do not initialize channels that are not connected */
488 if (pdata->led_config[i].led_current == 0)
491 led_current = pdata->led_config[i].led_current;
493 ret = lp55xx_init_led(each, chip, i);
497 INIT_WORK(&each->brightness_work, cfg->brightness_work_fn);
502 /* setting led current at each channel */
503 if (cfg->set_led_current)
504 cfg->set_led_current(each, led_current);
510 lp55xx_unregister_leds(led, chip);
513 EXPORT_SYMBOL_GPL(lp55xx_register_leds);
515 void lp55xx_unregister_leds(struct lp55xx_led *led, struct lp55xx_chip *chip)
518 struct lp55xx_led *each;
520 for (i = 0; i < chip->num_leds; i++) {
522 led_classdev_unregister(&each->cdev);
523 flush_work(&each->brightness_work);
526 EXPORT_SYMBOL_GPL(lp55xx_unregister_leds);
528 int lp55xx_register_sysfs(struct lp55xx_chip *chip)
530 struct device *dev = &chip->cl->dev;
531 struct lp55xx_device_config *cfg = chip->cfg;
534 if (!cfg->run_engine || !cfg->firmware_cb)
535 goto dev_specific_attrs;
537 ret = sysfs_create_group(&dev->kobj, &lp55xx_engine_attr_group);
542 return cfg->dev_attr_group ?
543 sysfs_create_group(&dev->kobj, cfg->dev_attr_group) : 0;
545 EXPORT_SYMBOL_GPL(lp55xx_register_sysfs);
547 void lp55xx_unregister_sysfs(struct lp55xx_chip *chip)
549 struct device *dev = &chip->cl->dev;
550 struct lp55xx_device_config *cfg = chip->cfg;
552 if (cfg->dev_attr_group)
553 sysfs_remove_group(&dev->kobj, cfg->dev_attr_group);
555 sysfs_remove_group(&dev->kobj, &lp55xx_engine_attr_group);
557 EXPORT_SYMBOL_GPL(lp55xx_unregister_sysfs);
559 int lp55xx_of_populate_pdata(struct device *dev, struct device_node *np)
561 struct device_node *child;
562 struct lp55xx_platform_data *pdata;
563 struct lp55xx_led_config *cfg;
567 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
571 num_channels = of_get_child_count(np);
572 if (num_channels == 0) {
573 dev_err(dev, "no LED channels\n");
577 cfg = devm_kzalloc(dev, sizeof(*cfg) * num_channels, GFP_KERNEL);
581 pdata->led_config = &cfg[0];
582 pdata->num_channels = num_channels;
584 for_each_child_of_node(np, child) {
587 of_property_read_string(child, "chan-name", &cfg[i].name);
588 of_property_read_u8(child, "led-cur", &cfg[i].led_current);
589 of_property_read_u8(child, "max-cur", &cfg[i].max_current);
590 cfg[i].default_trigger =
591 of_get_property(child, "linux,default-trigger", NULL);
596 of_property_read_string(np, "label", &pdata->label);
597 of_property_read_u8(np, "clock-mode", &pdata->clock_mode);
599 /* LP8501 specific */
600 of_property_read_u8(np, "pwr-sel", (u8 *)&pdata->pwr_sel);
602 dev->platform_data = pdata;
606 EXPORT_SYMBOL_GPL(lp55xx_of_populate_pdata);
608 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
609 MODULE_DESCRIPTION("LP55xx Common Driver");
610 MODULE_LICENSE("GPL");