1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * lm3533-bl.c -- LM3533 Backlight driver |
4 | * |
5 | * Copyright (C) 2011-2012 Texas Instruments |
6 | * |
7 | * Author: Johan Hovold <jhovold@gmail.com> |
8 | */ |
9 | |
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 | |
26 | struct lm3533_bl { |
27 | struct lm3533 *lm3533; |
28 | struct lm3533_ctrlbank cb; |
29 | struct backlight_device *bd; |
30 | int id; |
31 | }; |
32 | |
33 | |
34 | static inline int lm3533_bl_get_ctrlbank_id(struct lm3533_bl *bl) |
35 | { |
36 | return bl->id; |
37 | } |
38 | |
39 | static int lm3533_bl_update_status(struct backlight_device *bd) |
40 | { |
41 | struct lm3533_bl *bl = bl_get_data(bl_dev: bd); |
42 | |
43 | return lm3533_ctrlbank_set_brightness(cb: &bl->cb, val: backlight_get_brightness(bd)); |
44 | } |
45 | |
46 | static int lm3533_bl_get_brightness(struct backlight_device *bd) |
47 | { |
48 | struct lm3533_bl *bl = bl_get_data(bl_dev: bd); |
49 | u8 val; |
50 | int ret; |
51 | |
52 | ret = lm3533_ctrlbank_get_brightness(cb: &bl->cb, val: &val); |
53 | if (ret) |
54 | return ret; |
55 | |
56 | return val; |
57 | } |
58 | |
59 | static const struct backlight_ops lm3533_bl_ops = { |
60 | .get_brightness = lm3533_bl_get_brightness, |
61 | .update_status = lm3533_bl_update_status, |
62 | }; |
63 | |
64 | static 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, fmt: "%d\n" , bl->id); |
70 | } |
71 | |
72 | static 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, fmt: "%u\n" , channel); |
79 | } |
80 | |
81 | static 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(lm3533: bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val: &val); |
92 | if (ret) |
93 | return ret; |
94 | |
95 | mask = 1 << (2 * ctrlbank); |
96 | enable = val & mask; |
97 | |
98 | return scnprintf(buf, PAGE_SIZE, fmt: "%d\n" , enable); |
99 | } |
100 | |
101 | static 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(s: buf, base: 0, res: &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(lm3533: bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val, |
123 | mask); |
124 | if (ret) |
125 | return ret; |
126 | |
127 | return len; |
128 | } |
129 | |
130 | static 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(lm3533: bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val: &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, fmt: "%x\n" , linear); |
151 | } |
152 | |
153 | static 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(s: buf, base: 0, res: &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(lm3533: bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val, |
174 | mask); |
175 | if (ret) |
176 | return ret; |
177 | |
178 | return len; |
179 | } |
180 | |
181 | static 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(cb: &bl->cb, val: &val); |
190 | if (ret) |
191 | return ret; |
192 | |
193 | return scnprintf(buf, PAGE_SIZE, fmt: "%u\n" , val); |
194 | } |
195 | |
196 | static 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(s: buf, base: 0, res: &val)) |
205 | return -EINVAL; |
206 | |
207 | ret = lm3533_ctrlbank_set_pwm(cb: &bl->cb, val); |
208 | if (ret) |
209 | return ret; |
210 | |
211 | return len; |
212 | } |
213 | |
214 | static LM3533_ATTR_RO(als_channel); |
215 | static LM3533_ATTR_RW(als_en); |
216 | static LM3533_ATTR_RO(id); |
217 | static LM3533_ATTR_RW(linear); |
218 | static LM3533_ATTR_RW(pwm); |
219 | |
220 | static 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 | |
229 | static 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 | |
245 | static struct attribute_group lm3533_bl_attribute_group = { |
246 | .is_visible = lm3533_bl_attr_is_visible, |
247 | .attrs = lm3533_bl_attributes |
248 | }; |
249 | |
250 | static 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(cb: &bl->cb, imax: pdata->max_current); |
256 | if (ret) |
257 | return ret; |
258 | |
259 | return lm3533_ctrlbank_set_pwm(cb: &bl->cb, val: pdata->pwm); |
260 | } |
261 | |
262 | static 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(dev: pdev->dev.parent); |
274 | if (!lm3533) |
275 | return -EINVAL; |
276 | |
277 | pdata = dev_get_platdata(dev: &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(dev: &pdev->dev, size: 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; /* until registered */ |
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(dev: &pdev->dev, name: pdata->name, |
304 | parent: pdev->dev.parent, devdata: bl, ops: &lm3533_bl_ops, |
305 | props: &props); |
306 | if (IS_ERR(ptr: bd)) { |
307 | dev_err(&pdev->dev, "failed to register backlight device\n" ); |
308 | return PTR_ERR(ptr: bd); |
309 | } |
310 | |
311 | bl->bd = bd; |
312 | bl->cb.dev = &bl->bd->dev; |
313 | |
314 | platform_set_drvdata(pdev, data: bl); |
315 | |
316 | ret = sysfs_create_group(kobj: &bd->dev.kobj, grp: &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(cb: &bl->cb); |
329 | if (ret) |
330 | goto err_sysfs_remove; |
331 | |
332 | return 0; |
333 | |
334 | err_sysfs_remove: |
335 | sysfs_remove_group(kobj: &bd->dev.kobj, grp: &lm3533_bl_attribute_group); |
336 | |
337 | return ret; |
338 | } |
339 | |
340 | static void 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(cb: &bl->cb); |
351 | sysfs_remove_group(kobj: &bd->dev.kobj, grp: &lm3533_bl_attribute_group); |
352 | } |
353 | |
354 | #ifdef CONFIG_PM_SLEEP |
355 | static int lm3533_bl_suspend(struct device *dev) |
356 | { |
357 | struct lm3533_bl *bl = dev_get_drvdata(dev); |
358 | |
359 | dev_dbg(dev, "%s\n" , __func__); |
360 | |
361 | return lm3533_ctrlbank_disable(cb: &bl->cb); |
362 | } |
363 | |
364 | static int lm3533_bl_resume(struct device *dev) |
365 | { |
366 | struct lm3533_bl *bl = dev_get_drvdata(dev); |
367 | |
368 | dev_dbg(dev, "%s\n" , __func__); |
369 | |
370 | return lm3533_ctrlbank_enable(cb: &bl->cb); |
371 | } |
372 | #endif |
373 | |
374 | static SIMPLE_DEV_PM_OPS(lm3533_bl_pm_ops, lm3533_bl_suspend, lm3533_bl_resume); |
375 | |
376 | static void lm3533_bl_shutdown(struct platform_device *pdev) |
377 | { |
378 | struct lm3533_bl *bl = platform_get_drvdata(pdev); |
379 | |
380 | dev_dbg(&pdev->dev, "%s\n" , __func__); |
381 | |
382 | lm3533_ctrlbank_disable(cb: &bl->cb); |
383 | } |
384 | |
385 | static struct platform_driver lm3533_bl_driver = { |
386 | .driver = { |
387 | .name = "lm3533-backlight" , |
388 | .pm = &lm3533_bl_pm_ops, |
389 | }, |
390 | .probe = lm3533_bl_probe, |
391 | .remove_new = lm3533_bl_remove, |
392 | .shutdown = lm3533_bl_shutdown, |
393 | }; |
394 | module_platform_driver(lm3533_bl_driver); |
395 | |
396 | MODULE_AUTHOR("Johan Hovold <jhovold@gmail.com>" ); |
397 | MODULE_DESCRIPTION("LM3533 Backlight driver" ); |
398 | MODULE_LICENSE("GPL" ); |
399 | MODULE_ALIAS("platform:lm3533-backlight" ); |
400 | |