2 * lm3533-bl.c -- LM3533 Backlight driver
4 * Copyright (C) 2011-2012 Texas Instruments
6 * Author: Johan Hovold <jhovold@gmail.com>
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version.
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/platform_device.h>
17 #include <linux/backlight.h>
19 #include <linux/slab.h>
21 #include <linux/mfd/lm3533.h>
24 #define LM3533_HVCTRLBANK_COUNT 2
25 #define LM3533_BL_MAX_BRIGHTNESS 255
27 #define LM3533_REG_CTRLBANK_AB_BCONF 0x1a
31 struct lm3533 *lm3533;
32 struct lm3533_ctrlbank cb;
33 struct backlight_device *bd;
38 static inline int lm3533_bl_get_ctrlbank_id(struct lm3533_bl *bl)
43 static int lm3533_bl_update_status(struct backlight_device *bd)
45 struct lm3533_bl *bl = bl_get_data(bd);
46 int brightness = bd->props.brightness;
48 if (bd->props.power != FB_BLANK_UNBLANK)
50 if (bd->props.fb_blank != FB_BLANK_UNBLANK)
53 return lm3533_ctrlbank_set_brightness(&bl->cb, (u8)brightness);
56 static int lm3533_bl_get_brightness(struct backlight_device *bd)
58 struct lm3533_bl *bl = bl_get_data(bd);
62 ret = lm3533_ctrlbank_get_brightness(&bl->cb, &val);
69 static const struct backlight_ops lm3533_bl_ops = {
70 .get_brightness = lm3533_bl_get_brightness,
71 .update_status = lm3533_bl_update_status,
74 static ssize_t show_id(struct device *dev,
75 struct device_attribute *attr, char *buf)
77 struct lm3533_bl *bl = dev_get_drvdata(dev);
79 return scnprintf(buf, PAGE_SIZE, "%d\n", bl->id);
82 static ssize_t show_als_channel(struct device *dev,
83 struct device_attribute *attr, char *buf)
85 struct lm3533_bl *bl = dev_get_drvdata(dev);
86 unsigned channel = lm3533_bl_get_ctrlbank_id(bl);
88 return scnprintf(buf, PAGE_SIZE, "%u\n", channel);
91 static ssize_t show_als_en(struct device *dev,
92 struct device_attribute *attr, char *buf)
94 struct lm3533_bl *bl = dev_get_drvdata(dev);
95 int ctrlbank = lm3533_bl_get_ctrlbank_id(bl);
101 ret = lm3533_read(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, &val);
105 mask = 1 << (2 * ctrlbank);
108 return scnprintf(buf, PAGE_SIZE, "%d\n", enable);
111 static ssize_t store_als_en(struct device *dev,
112 struct device_attribute *attr,
113 const char *buf, size_t len)
115 struct lm3533_bl *bl = dev_get_drvdata(dev);
116 int ctrlbank = lm3533_bl_get_ctrlbank_id(bl);
122 if (kstrtoint(buf, 0, &enable))
125 mask = 1 << (2 * ctrlbank);
132 ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val,
140 static ssize_t show_linear(struct device *dev,
141 struct device_attribute *attr, char *buf)
143 struct lm3533_bl *bl = dev_get_drvdata(dev);
149 ret = lm3533_read(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, &val);
153 mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1);
160 return scnprintf(buf, PAGE_SIZE, "%x\n", linear);
163 static ssize_t store_linear(struct device *dev,
164 struct device_attribute *attr,
165 const char *buf, size_t len)
167 struct lm3533_bl *bl = dev_get_drvdata(dev);
168 unsigned long linear;
173 if (kstrtoul(buf, 0, &linear))
176 mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1);
183 ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val,
191 static ssize_t show_pwm(struct device *dev,
192 struct device_attribute *attr,
195 struct lm3533_bl *bl = dev_get_drvdata(dev);
199 ret = lm3533_ctrlbank_get_pwm(&bl->cb, &val);
203 return scnprintf(buf, PAGE_SIZE, "%u\n", val);
206 static ssize_t store_pwm(struct device *dev,
207 struct device_attribute *attr,
208 const char *buf, size_t len)
210 struct lm3533_bl *bl = dev_get_drvdata(dev);
214 if (kstrtou8(buf, 0, &val))
217 ret = lm3533_ctrlbank_set_pwm(&bl->cb, val);
224 static LM3533_ATTR_RO(als_channel);
225 static LM3533_ATTR_RW(als_en);
226 static LM3533_ATTR_RO(id);
227 static LM3533_ATTR_RW(linear);
228 static LM3533_ATTR_RW(pwm);
230 static struct attribute *lm3533_bl_attributes[] = {
231 &dev_attr_als_channel.attr,
232 &dev_attr_als_en.attr,
234 &dev_attr_linear.attr,
239 static umode_t lm3533_bl_attr_is_visible(struct kobject *kobj,
240 struct attribute *attr, int n)
242 struct device *dev = container_of(kobj, struct device, kobj);
243 struct lm3533_bl *bl = dev_get_drvdata(dev);
244 umode_t mode = attr->mode;
246 if (attr == &dev_attr_als_channel.attr ||
247 attr == &dev_attr_als_en.attr) {
248 if (!bl->lm3533->have_als)
255 static struct attribute_group lm3533_bl_attribute_group = {
256 .is_visible = lm3533_bl_attr_is_visible,
257 .attrs = lm3533_bl_attributes
260 static int __devinit lm3533_bl_setup(struct lm3533_bl *bl,
261 struct lm3533_bl_platform_data *pdata)
265 ret = lm3533_ctrlbank_set_max_current(&bl->cb, pdata->max_current);
269 return lm3533_ctrlbank_set_pwm(&bl->cb, pdata->pwm);
272 static int __devinit lm3533_bl_probe(struct platform_device *pdev)
274 struct lm3533 *lm3533;
275 struct lm3533_bl_platform_data *pdata;
276 struct lm3533_bl *bl;
277 struct backlight_device *bd;
278 struct backlight_properties props;
281 dev_dbg(&pdev->dev, "%s\n", __func__);
283 lm3533 = dev_get_drvdata(pdev->dev.parent);
287 pdata = pdev->dev.platform_data;
289 dev_err(&pdev->dev, "no platform data\n");
293 if (pdev->id < 0 || pdev->id >= LM3533_HVCTRLBANK_COUNT) {
294 dev_err(&pdev->dev, "illegal backlight id %d\n", pdev->id);
298 bl = kzalloc(sizeof(*bl), GFP_KERNEL);
301 "failed to allocate memory for backlight\n");
308 bl->cb.lm3533 = lm3533;
309 bl->cb.id = lm3533_bl_get_ctrlbank_id(bl);
310 bl->cb.dev = NULL; /* until registered */
312 memset(&props, 0, sizeof(props));
313 props.type = BACKLIGHT_RAW;
314 props.max_brightness = LM3533_BL_MAX_BRIGHTNESS;
315 props.brightness = pdata->default_brightness;
316 bd = backlight_device_register(pdata->name, pdev->dev.parent, bl,
317 &lm3533_bl_ops, &props);
319 dev_err(&pdev->dev, "failed to register backlight device\n");
325 bl->cb.dev = &bl->bd->dev;
327 platform_set_drvdata(pdev, bl);
329 ret = sysfs_create_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
331 dev_err(&pdev->dev, "failed to create sysfs attributes\n");
335 backlight_update_status(bd);
337 ret = lm3533_bl_setup(bl, pdata);
339 goto err_sysfs_remove;
341 ret = lm3533_ctrlbank_enable(&bl->cb);
343 goto err_sysfs_remove;
348 sysfs_remove_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
350 backlight_device_unregister(bd);
357 static int __devexit lm3533_bl_remove(struct platform_device *pdev)
359 struct lm3533_bl *bl = platform_get_drvdata(pdev);
360 struct backlight_device *bd = bl->bd;
362 dev_dbg(&bd->dev, "%s\n", __func__);
364 bd->props.power = FB_BLANK_POWERDOWN;
365 bd->props.brightness = 0;
367 lm3533_ctrlbank_disable(&bl->cb);
368 sysfs_remove_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
369 backlight_device_unregister(bd);
376 static int lm3533_bl_suspend(struct platform_device *pdev, pm_message_t state)
378 struct lm3533_bl *bl = platform_get_drvdata(pdev);
380 dev_dbg(&pdev->dev, "%s\n", __func__);
382 return lm3533_ctrlbank_disable(&bl->cb);
385 static int lm3533_bl_resume(struct platform_device *pdev)
387 struct lm3533_bl *bl = platform_get_drvdata(pdev);
389 dev_dbg(&pdev->dev, "%s\n", __func__);
391 return lm3533_ctrlbank_enable(&bl->cb);
394 #define lm3533_bl_suspend NULL
395 #define lm3533_bl_resume NULL
398 static void lm3533_bl_shutdown(struct platform_device *pdev)
400 struct lm3533_bl *bl = platform_get_drvdata(pdev);
402 dev_dbg(&pdev->dev, "%s\n", __func__);
404 lm3533_ctrlbank_disable(&bl->cb);
407 static struct platform_driver lm3533_bl_driver = {
409 .name = "lm3533-backlight",
410 .owner = THIS_MODULE,
412 .probe = lm3533_bl_probe,
413 .remove = __devexit_p(lm3533_bl_remove),
414 .shutdown = lm3533_bl_shutdown,
415 .suspend = lm3533_bl_suspend,
416 .resume = lm3533_bl_resume,
418 module_platform_driver(lm3533_bl_driver);
420 MODULE_AUTHOR("Johan Hovold <jhovold@gmail.com>");
421 MODULE_DESCRIPTION("LM3533 Backlight driver");
422 MODULE_LICENSE("GPL");
423 MODULE_ALIAS("platform:lm3533-backlight");