1
2
3
4
5
6
7
8
9
10
11
12
13
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/platform_device.h>
17#include <linux/backlight.h>
18#include <linux/fb.h>
19#include <linux/slab.h>
20
21#include <linux/mfd/lm3533.h>
22
23
24#define LM3533_HVCTRLBANK_COUNT 2
25#define LM3533_BL_MAX_BRIGHTNESS 255
26
27#define LM3533_REG_CTRLBANK_AB_BCONF 0x1a
28
29
30struct lm3533_bl {
31 struct lm3533 *lm3533;
32 struct lm3533_ctrlbank cb;
33 struct backlight_device *bd;
34 int id;
35};
36
37
38static inline int lm3533_bl_get_ctrlbank_id(struct lm3533_bl *bl)
39{
40 return bl->id;
41}
42
43static int lm3533_bl_update_status(struct backlight_device *bd)
44{
45 struct lm3533_bl *bl = bl_get_data(bd);
46 int brightness = bd->props.brightness;
47
48 if (bd->props.power != FB_BLANK_UNBLANK)
49 brightness = 0;
50 if (bd->props.fb_blank != FB_BLANK_UNBLANK)
51 brightness = 0;
52
53 return lm3533_ctrlbank_set_brightness(&bl->cb, (u8)brightness);
54}
55
56static int lm3533_bl_get_brightness(struct backlight_device *bd)
57{
58 struct lm3533_bl *bl = bl_get_data(bd);
59 u8 val;
60 int ret;
61
62 ret = lm3533_ctrlbank_get_brightness(&bl->cb, &val);
63 if (ret)
64 return ret;
65
66 return val;
67}
68
69static const struct backlight_ops lm3533_bl_ops = {
70 .get_brightness = lm3533_bl_get_brightness,
71 .update_status = lm3533_bl_update_status,
72};
73
74static ssize_t show_id(struct device *dev,
75 struct device_attribute *attr, char *buf)
76{
77 struct lm3533_bl *bl = dev_get_drvdata(dev);
78
79 return scnprintf(buf, PAGE_SIZE, "%d\n", bl->id);
80}
81
82static ssize_t show_als_channel(struct device *dev,
83 struct device_attribute *attr, char *buf)
84{
85 struct lm3533_bl *bl = dev_get_drvdata(dev);
86 unsigned channel = lm3533_bl_get_ctrlbank_id(bl);
87
88 return scnprintf(buf, PAGE_SIZE, "%u\n", channel);
89}
90
91static ssize_t show_als_en(struct device *dev,
92 struct device_attribute *attr, char *buf)
93{
94 struct lm3533_bl *bl = dev_get_drvdata(dev);
95 int ctrlbank = lm3533_bl_get_ctrlbank_id(bl);
96 u8 val;
97 u8 mask;
98 bool enable;
99 int ret;
100
101 ret = lm3533_read(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, &val);
102 if (ret)
103 return ret;
104
105 mask = 1 << (2 * ctrlbank);
106 enable = val & mask;
107
108 return scnprintf(buf, PAGE_SIZE, "%d\n", enable);
109}
110
111static ssize_t store_als_en(struct device *dev,
112 struct device_attribute *attr,
113 const char *buf, size_t len)
114{
115 struct lm3533_bl *bl = dev_get_drvdata(dev);
116 int ctrlbank = lm3533_bl_get_ctrlbank_id(bl);
117 int enable;
118 u8 val;
119 u8 mask;
120 int ret;
121
122 if (kstrtoint(buf, 0, &enable))
123 return -EINVAL;
124
125 mask = 1 << (2 * ctrlbank);
126
127 if (enable)
128 val = mask;
129 else
130 val = 0;
131
132 ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val,
133 mask);
134 if (ret)
135 return ret;
136
137 return len;
138}
139
140static ssize_t show_linear(struct device *dev,
141 struct device_attribute *attr, char *buf)
142{
143 struct lm3533_bl *bl = dev_get_drvdata(dev);
144 u8 val;
145 u8 mask;
146 int linear;
147 int ret;
148
149 ret = lm3533_read(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, &val);
150 if (ret)
151 return ret;
152
153 mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1);
154
155 if (val & mask)
156 linear = 1;
157 else
158 linear = 0;
159
160 return scnprintf(buf, PAGE_SIZE, "%x\n", linear);
161}
162
163static ssize_t store_linear(struct device *dev,
164 struct device_attribute *attr,
165 const char *buf, size_t len)
166{
167 struct lm3533_bl *bl = dev_get_drvdata(dev);
168 unsigned long linear;
169 u8 mask;
170 u8 val;
171 int ret;
172
173 if (kstrtoul(buf, 0, &linear))
174 return -EINVAL;
175
176 mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1);
177
178 if (linear)
179 val = mask;
180 else
181 val = 0;
182
183 ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val,
184 mask);
185 if (ret)
186 return ret;
187
188 return len;
189}
190
191static ssize_t show_pwm(struct device *dev,
192 struct device_attribute *attr,
193 char *buf)
194{
195 struct lm3533_bl *bl = dev_get_drvdata(dev);
196 u8 val;
197 int ret;
198
199 ret = lm3533_ctrlbank_get_pwm(&bl->cb, &val);
200 if (ret)
201 return ret;
202
203 return scnprintf(buf, PAGE_SIZE, "%u\n", val);
204}
205
206static ssize_t store_pwm(struct device *dev,
207 struct device_attribute *attr,
208 const char *buf, size_t len)
209{
210 struct lm3533_bl *bl = dev_get_drvdata(dev);
211 u8 val;
212 int ret;
213
214 if (kstrtou8(buf, 0, &val))
215 return -EINVAL;
216
217 ret = lm3533_ctrlbank_set_pwm(&bl->cb, val);
218 if (ret)
219 return ret;
220
221 return len;
222}
223
224static LM3533_ATTR_RO(als_channel);
225static LM3533_ATTR_RW(als_en);
226static LM3533_ATTR_RO(id);
227static LM3533_ATTR_RW(linear);
228static LM3533_ATTR_RW(pwm);
229
230static struct attribute *lm3533_bl_attributes[] = {
231 &dev_attr_als_channel.attr,
232 &dev_attr_als_en.attr,
233 &dev_attr_id.attr,
234 &dev_attr_linear.attr,
235 &dev_attr_pwm.attr,
236 NULL,
237};
238
239static umode_t lm3533_bl_attr_is_visible(struct kobject *kobj,
240 struct attribute *attr, int n)
241{
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;
245
246 if (attr == &dev_attr_als_channel.attr ||
247 attr == &dev_attr_als_en.attr) {
248 if (!bl->lm3533->have_als)
249 mode = 0;
250 }
251
252 return mode;
253};
254
255static struct attribute_group lm3533_bl_attribute_group = {
256 .is_visible = lm3533_bl_attr_is_visible,
257 .attrs = lm3533_bl_attributes
258};
259
260static int lm3533_bl_setup(struct lm3533_bl *bl,
261 struct lm3533_bl_platform_data *pdata)
262{
263 int ret;
264
265 ret = lm3533_ctrlbank_set_max_current(&bl->cb, pdata->max_current);
266 if (ret)
267 return ret;
268
269 return lm3533_ctrlbank_set_pwm(&bl->cb, pdata->pwm);
270}
271
272static int lm3533_bl_probe(struct platform_device *pdev)
273{
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;
279 int ret;
280
281 dev_dbg(&pdev->dev, "%s\n", __func__);
282
283 lm3533 = dev_get_drvdata(pdev->dev.parent);
284 if (!lm3533)
285 return -EINVAL;
286
287 pdata = dev_get_platdata(&pdev->dev);
288 if (!pdata) {
289 dev_err(&pdev->dev, "no platform data\n");
290 return -EINVAL;
291 }
292
293 if (pdev->id < 0 || pdev->id >= LM3533_HVCTRLBANK_COUNT) {
294 dev_err(&pdev->dev, "illegal backlight id %d\n", pdev->id);
295 return -EINVAL;
296 }
297
298 bl = devm_kzalloc(&pdev->dev, sizeof(*bl), GFP_KERNEL);
299 if (!bl)
300 return -ENOMEM;
301
302 bl->lm3533 = lm3533;
303 bl->id = pdev->id;
304
305 bl->cb.lm3533 = lm3533;
306 bl->cb.id = lm3533_bl_get_ctrlbank_id(bl);
307 bl->cb.dev = NULL;
308
309 memset(&props, 0, sizeof(props));
310 props.type = BACKLIGHT_RAW;
311 props.max_brightness = LM3533_BL_MAX_BRIGHTNESS;
312 props.brightness = pdata->default_brightness;
313 bd = devm_backlight_device_register(&pdev->dev, pdata->name,
314 pdev->dev.parent, bl, &lm3533_bl_ops,
315 &props);
316 if (IS_ERR(bd)) {
317 dev_err(&pdev->dev, "failed to register backlight device\n");
318 return PTR_ERR(bd);
319 }
320
321 bl->bd = bd;
322 bl->cb.dev = &bl->bd->dev;
323
324 platform_set_drvdata(pdev, bl);
325
326 ret = sysfs_create_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
327 if (ret < 0) {
328 dev_err(&pdev->dev, "failed to create sysfs attributes\n");
329 return ret;
330 }
331
332 backlight_update_status(bd);
333
334 ret = lm3533_bl_setup(bl, pdata);
335 if (ret)
336 goto err_sysfs_remove;
337
338 ret = lm3533_ctrlbank_enable(&bl->cb);
339 if (ret)
340 goto err_sysfs_remove;
341
342 return 0;
343
344err_sysfs_remove:
345 sysfs_remove_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
346
347 return ret;
348}
349
350static int lm3533_bl_remove(struct platform_device *pdev)
351{
352 struct lm3533_bl *bl = platform_get_drvdata(pdev);
353 struct backlight_device *bd = bl->bd;
354
355 dev_dbg(&bd->dev, "%s\n", __func__);
356
357 bd->props.power = FB_BLANK_POWERDOWN;
358 bd->props.brightness = 0;
359
360 lm3533_ctrlbank_disable(&bl->cb);
361 sysfs_remove_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
362
363 return 0;
364}
365
366#ifdef CONFIG_PM_SLEEP
367static int lm3533_bl_suspend(struct device *dev)
368{
369 struct lm3533_bl *bl = dev_get_drvdata(dev);
370
371 dev_dbg(dev, "%s\n", __func__);
372
373 return lm3533_ctrlbank_disable(&bl->cb);
374}
375
376static int lm3533_bl_resume(struct device *dev)
377{
378 struct lm3533_bl *bl = dev_get_drvdata(dev);
379
380 dev_dbg(dev, "%s\n", __func__);
381
382 return lm3533_ctrlbank_enable(&bl->cb);
383}
384#endif
385
386static SIMPLE_DEV_PM_OPS(lm3533_bl_pm_ops, lm3533_bl_suspend, lm3533_bl_resume);
387
388static void lm3533_bl_shutdown(struct platform_device *pdev)
389{
390 struct lm3533_bl *bl = platform_get_drvdata(pdev);
391
392 dev_dbg(&pdev->dev, "%s\n", __func__);
393
394 lm3533_ctrlbank_disable(&bl->cb);
395}
396
397static struct platform_driver lm3533_bl_driver = {
398 .driver = {
399 .name = "lm3533-backlight",
400 .pm = &lm3533_bl_pm_ops,
401 },
402 .probe = lm3533_bl_probe,
403 .remove = lm3533_bl_remove,
404 .shutdown = lm3533_bl_shutdown,
405};
406module_platform_driver(lm3533_bl_driver);
407
408MODULE_AUTHOR("Johan Hovold <jhovold@gmail.com>");
409MODULE_DESCRIPTION("LM3533 Backlight driver");
410MODULE_LICENSE("GPL");
411MODULE_ALIAS("platform:lm3533-backlight");
412
