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10#include <linux/module.h>
11#include <linux/init.h>
12#include <linux/platform_device.h>
13#include <linux/backlight.h>
14#include <linux/fb.h>
15#include <linux/slab.h>
16
17#include <linux/mfd/lm3533.h>
18
19
20#define LM3533_HVCTRLBANK_COUNT 2
21#define LM3533_BL_MAX_BRIGHTNESS 255
22
23#define LM3533_REG_CTRLBANK_AB_BCONF 0x1a
24
25
26struct lm3533_bl {
27 struct lm3533 *lm3533;
28 struct lm3533_ctrlbank cb;
29 struct backlight_device *bd;
30 int id;
31};
32
33
34static inline int lm3533_bl_get_ctrlbank_id(struct lm3533_bl *bl)
35{
36 return bl->id;
37}
38
39static int lm3533_bl_update_status(struct backlight_device *bd)
40{
41 struct lm3533_bl *bl = bl_get_data(bd);
42
43 return lm3533_ctrlbank_set_brightness(&bl->cb, backlight_get_brightness(bd));
44}
45
46static int lm3533_bl_get_brightness(struct backlight_device *bd)
47{
48 struct lm3533_bl *bl = bl_get_data(bd);
49 u8 val;
50 int ret;
51
52 ret = lm3533_ctrlbank_get_brightness(&bl->cb, &val);
53 if (ret)
54 return ret;
55
56 return val;
57}
58
59static const struct backlight_ops lm3533_bl_ops = {
60 .get_brightness = lm3533_bl_get_brightness,
61 .update_status = lm3533_bl_update_status,
62};
63
64static ssize_t show_id(struct device *dev,
65 struct device_attribute *attr, char *buf)
66{
67 struct lm3533_bl *bl = dev_get_drvdata(dev);
68
69 return scnprintf(buf, PAGE_SIZE, "%d\n", bl->id);
70}
71
72static ssize_t show_als_channel(struct device *dev,
73 struct device_attribute *attr, char *buf)
74{
75 struct lm3533_bl *bl = dev_get_drvdata(dev);
76 unsigned channel = lm3533_bl_get_ctrlbank_id(bl);
77
78 return scnprintf(buf, PAGE_SIZE, "%u\n", channel);
79}
80
81static ssize_t show_als_en(struct device *dev,
82 struct device_attribute *attr, char *buf)
83{
84 struct lm3533_bl *bl = dev_get_drvdata(dev);
85 int ctrlbank = lm3533_bl_get_ctrlbank_id(bl);
86 u8 val;
87 u8 mask;
88 bool enable;
89 int ret;
90
91 ret = lm3533_read(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, &val);
92 if (ret)
93 return ret;
94
95 mask = 1 << (2 * ctrlbank);
96 enable = val & mask;
97
98 return scnprintf(buf, PAGE_SIZE, "%d\n", enable);
99}
100
101static ssize_t store_als_en(struct device *dev,
102 struct device_attribute *attr,
103 const char *buf, size_t len)
104{
105 struct lm3533_bl *bl = dev_get_drvdata(dev);
106 int ctrlbank = lm3533_bl_get_ctrlbank_id(bl);
107 int enable;
108 u8 val;
109 u8 mask;
110 int ret;
111
112 if (kstrtoint(buf, 0, &enable))
113 return -EINVAL;
114
115 mask = 1 << (2 * ctrlbank);
116
117 if (enable)
118 val = mask;
119 else
120 val = 0;
121
122 ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val,
123 mask);
124 if (ret)
125 return ret;
126
127 return len;
128}
129
130static ssize_t show_linear(struct device *dev,
131 struct device_attribute *attr, char *buf)
132{
133 struct lm3533_bl *bl = dev_get_drvdata(dev);
134 u8 val;
135 u8 mask;
136 int linear;
137 int ret;
138
139 ret = lm3533_read(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, &val);
140 if (ret)
141 return ret;
142
143 mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1);
144
145 if (val & mask)
146 linear = 1;
147 else
148 linear = 0;
149
150 return scnprintf(buf, PAGE_SIZE, "%x\n", linear);
151}
152
153static ssize_t store_linear(struct device *dev,
154 struct device_attribute *attr,
155 const char *buf, size_t len)
156{
157 struct lm3533_bl *bl = dev_get_drvdata(dev);
158 unsigned long linear;
159 u8 mask;
160 u8 val;
161 int ret;
162
163 if (kstrtoul(buf, 0, &linear))
164 return -EINVAL;
165
166 mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1);
167
168 if (linear)
169 val = mask;
170 else
171 val = 0;
172
173 ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val,
174 mask);
175 if (ret)
176 return ret;
177
178 return len;
179}
180
181static ssize_t show_pwm(struct device *dev,
182 struct device_attribute *attr,
183 char *buf)
184{
185 struct lm3533_bl *bl = dev_get_drvdata(dev);
186 u8 val;
187 int ret;
188
189 ret = lm3533_ctrlbank_get_pwm(&bl->cb, &val);
190 if (ret)
191 return ret;
192
193 return scnprintf(buf, PAGE_SIZE, "%u\n", val);
194}
195
196static ssize_t store_pwm(struct device *dev,
197 struct device_attribute *attr,
198 const char *buf, size_t len)
199{
200 struct lm3533_bl *bl = dev_get_drvdata(dev);
201 u8 val;
202 int ret;
203
204 if (kstrtou8(buf, 0, &val))
205 return -EINVAL;
206
207 ret = lm3533_ctrlbank_set_pwm(&bl->cb, val);
208 if (ret)
209 return ret;
210
211 return len;
212}
213
214static LM3533_ATTR_RO(als_channel);
215static LM3533_ATTR_RW(als_en);
216static LM3533_ATTR_RO(id);
217static LM3533_ATTR_RW(linear);
218static LM3533_ATTR_RW(pwm);
219
220static struct attribute *lm3533_bl_attributes[] = {
221 &dev_attr_als_channel.attr,
222 &dev_attr_als_en.attr,
223 &dev_attr_id.attr,
224 &dev_attr_linear.attr,
225 &dev_attr_pwm.attr,
226 NULL,
227};
228
229static umode_t lm3533_bl_attr_is_visible(struct kobject *kobj,
230 struct attribute *attr, int n)
231{
232 struct device *dev = kobj_to_dev(kobj);
233 struct lm3533_bl *bl = dev_get_drvdata(dev);
234 umode_t mode = attr->mode;
235
236 if (attr == &dev_attr_als_channel.attr ||
237 attr == &dev_attr_als_en.attr) {
238 if (!bl->lm3533->have_als)
239 mode = 0;
240 }
241
242 return mode;
243};
244
245static struct attribute_group lm3533_bl_attribute_group = {
246 .is_visible = lm3533_bl_attr_is_visible,
247 .attrs = lm3533_bl_attributes
248};
249
250static int lm3533_bl_setup(struct lm3533_bl *bl,
251 struct lm3533_bl_platform_data *pdata)
252{
253 int ret;
254
255 ret = lm3533_ctrlbank_set_max_current(&bl->cb, pdata->max_current);
256 if (ret)
257 return ret;
258
259 return lm3533_ctrlbank_set_pwm(&bl->cb, pdata->pwm);
260}
261
262static int lm3533_bl_probe(struct platform_device *pdev)
263{
264 struct lm3533 *lm3533;
265 struct lm3533_bl_platform_data *pdata;
266 struct lm3533_bl *bl;
267 struct backlight_device *bd;
268 struct backlight_properties props;
269 int ret;
270
271 dev_dbg(&pdev->dev, "%s\n", __func__);
272
273 lm3533 = dev_get_drvdata(pdev->dev.parent);
274 if (!lm3533)
275 return -EINVAL;
276
277 pdata = dev_get_platdata(&pdev->dev);
278 if (!pdata) {
279 dev_err(&pdev->dev, "no platform data\n");
280 return -EINVAL;
281 }
282
283 if (pdev->id < 0 || pdev->id >= LM3533_HVCTRLBANK_COUNT) {
284 dev_err(&pdev->dev, "illegal backlight id %d\n", pdev->id);
285 return -EINVAL;
286 }
287
288 bl = devm_kzalloc(&pdev->dev, sizeof(*bl), GFP_KERNEL);
289 if (!bl)
290 return -ENOMEM;
291
292 bl->lm3533 = lm3533;
293 bl->id = pdev->id;
294
295 bl->cb.lm3533 = lm3533;
296 bl->cb.id = lm3533_bl_get_ctrlbank_id(bl);
297 bl->cb.dev = NULL;
298
299 memset(&props, 0, sizeof(props));
300 props.type = BACKLIGHT_RAW;
301 props.max_brightness = LM3533_BL_MAX_BRIGHTNESS;
302 props.brightness = pdata->default_brightness;
303 bd = devm_backlight_device_register(&pdev->dev, pdata->name,
304 pdev->dev.parent, bl, &lm3533_bl_ops,
305 &props);
306 if (IS_ERR(bd)) {
307 dev_err(&pdev->dev, "failed to register backlight device\n");
308 return PTR_ERR(bd);
309 }
310
311 bl->bd = bd;
312 bl->cb.dev = &bl->bd->dev;
313
314 platform_set_drvdata(pdev, bl);
315
316 ret = sysfs_create_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
317 if (ret < 0) {
318 dev_err(&pdev->dev, "failed to create sysfs attributes\n");
319 return ret;
320 }
321
322 backlight_update_status(bd);
323
324 ret = lm3533_bl_setup(bl, pdata);
325 if (ret)
326 goto err_sysfs_remove;
327
328 ret = lm3533_ctrlbank_enable(&bl->cb);
329 if (ret)
330 goto err_sysfs_remove;
331
332 return 0;
333
334err_sysfs_remove:
335 sysfs_remove_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
336
337 return ret;
338}
339
340static int lm3533_bl_remove(struct platform_device *pdev)
341{
342 struct lm3533_bl *bl = platform_get_drvdata(pdev);
343 struct backlight_device *bd = bl->bd;
344
345 dev_dbg(&bd->dev, "%s\n", __func__);
346
347 bd->props.power = FB_BLANK_POWERDOWN;
348 bd->props.brightness = 0;
349
350 lm3533_ctrlbank_disable(&bl->cb);
351 sysfs_remove_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
352
353 return 0;
354}
355
356#ifdef CONFIG_PM_SLEEP
357static int lm3533_bl_suspend(struct device *dev)
358{
359 struct lm3533_bl *bl = dev_get_drvdata(dev);
360
361 dev_dbg(dev, "%s\n", __func__);
362
363 return lm3533_ctrlbank_disable(&bl->cb);
364}
365
366static int lm3533_bl_resume(struct device *dev)
367{
368 struct lm3533_bl *bl = dev_get_drvdata(dev);
369
370 dev_dbg(dev, "%s\n", __func__);
371
372 return lm3533_ctrlbank_enable(&bl->cb);
373}
374#endif
375
376static SIMPLE_DEV_PM_OPS(lm3533_bl_pm_ops, lm3533_bl_suspend, lm3533_bl_resume);
377
378static void lm3533_bl_shutdown(struct platform_device *pdev)
379{
380 struct lm3533_bl *bl = platform_get_drvdata(pdev);
381
382 dev_dbg(&pdev->dev, "%s\n", __func__);
383
384 lm3533_ctrlbank_disable(&bl->cb);
385}
386
387static struct platform_driver lm3533_bl_driver = {
388 .driver = {
389 .name = "lm3533-backlight",
390 .pm = &lm3533_bl_pm_ops,
391 },
392 .probe = lm3533_bl_probe,
393 .remove = lm3533_bl_remove,
394 .shutdown = lm3533_bl_shutdown,
395};
396module_platform_driver(lm3533_bl_driver);
397
398MODULE_AUTHOR("Johan Hovold <jhovold@gmail.com>");
399MODULE_DESCRIPTION("LM3533 Backlight driver");
400MODULE_LICENSE("GPL");
401MODULE_ALIAS("platform:lm3533-backlight");
402
