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PM / sleep: Asynchronous threads for suspend_noirq
[linux/fpc-iii.git] / drivers / regulator / max8660.c
blob8d94d3d7f97f22336fb973d5659ed50b4a3e6a97
1 /*
2 * max8660.c -- Voltage regulation for the Maxim 8660/8661
3 *
4 * based on max1586.c and wm8400-regulator.c
5 *
6 * Copyright (C) 2009 Wolfram Sang, Pengutronix e.K.
7 *
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 Free
10 * Software Foundation; version 2 of the License.
11 *
12 * This program is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * more details.
16 *
17 * You should have received a copy of the GNU General Public License along with
18 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
19 * Place, Suite 330, Boston, MA 02111-1307 USA
20 *
21 * Some info:
22 *
23 * Datasheet: http://datasheets.maxim-ic.com/en/ds/MAX8660-MAX8661.pdf
24 *
25 * This chip is a bit nasty because it is a write-only device. Thus, the driver
26 * uses shadow registers to keep track of its values. The main problem appears
27 * to be the initialization: When Linux boots up, we cannot know if the chip is
28 * in the default state or not, so we would have to pass such information in
29 * platform_data. As this adds a bit of complexity to the driver, this is left
30 * out for now until it is really needed.
31 *
32 * [A|S|M]DTV1 registers are currently not used, but [A|S|M]DTV2.
33 *
34 * If the driver is feature complete, it might be worth to check if one set of
35 * functions for V3-V7 is sufficient. For maximum flexibility during
36 * development, they are separated for now.
37 *
38 */
39
40 #include <linux/module.h>
41 #include <linux/err.h>
42 #include <linux/i2c.h>
43 #include <linux/platform_device.h>
44 #include <linux/regulator/driver.h>
45 #include <linux/slab.h>
46 #include <linux/regulator/max8660.h>
47 #include <linux/of.h>
48 #include <linux/of_device.h>
49 #include <linux/regulator/of_regulator.h>
50
51 #define MAX8660_DCDC_MIN_UV 725000
52 #define MAX8660_DCDC_MAX_UV 1800000
53 #define MAX8660_DCDC_STEP 25000
54 #define MAX8660_DCDC_MAX_SEL 0x2b
55
56 #define MAX8660_LDO5_MIN_UV 1700000
57 #define MAX8660_LDO5_MAX_UV 2000000
58 #define MAX8660_LDO5_STEP 25000
59 #define MAX8660_LDO5_MAX_SEL 0x0c
60
61 #define MAX8660_LDO67_MIN_UV 1800000
62 #define MAX8660_LDO67_MAX_UV 3300000
63 #define MAX8660_LDO67_STEP 100000
64 #define MAX8660_LDO67_MAX_SEL 0x0f
65
66 enum {
67 MAX8660_OVER1,
68 MAX8660_OVER2,
69 MAX8660_VCC1,
70 MAX8660_ADTV1,
71 MAX8660_ADTV2,
72 MAX8660_SDTV1,
73 MAX8660_SDTV2,
74 MAX8660_MDTV1,
75 MAX8660_MDTV2,
76 MAX8660_L12VCR,
77 MAX8660_FPWM,
78 MAX8660_N_REGS, /* not a real register */
79 };
80
81 struct max8660 {
82 struct i2c_client *client;
83 u8 shadow_regs[MAX8660_N_REGS]; /* as chip is write only */
84 struct regulator_dev *rdev[];
85 };
86
87 static int max8660_write(struct max8660 *max8660, u8 reg, u8 mask, u8 val)
88 {
89 static const u8 max8660_addresses[MAX8660_N_REGS] =
90 { 0x10, 0x12, 0x20, 0x23, 0x24, 0x29, 0x2a, 0x32, 0x33, 0x39, 0x80 };
91
92 int ret;
93 u8 reg_val = (max8660->shadow_regs[reg] & mask) | val;
94 dev_vdbg(&max8660->client->dev, "Writing reg %02x with %02x\n",
95 max8660_addresses[reg], reg_val);
96
97 ret = i2c_smbus_write_byte_data(max8660->client,
98 max8660_addresses[reg], reg_val);
99 if (ret == 0)
100 max8660->shadow_regs[reg] = reg_val;
101
102 return ret;
103 }
104
105
106 /*
107 * DCDC functions
108 */
109
110 static int max8660_dcdc_is_enabled(struct regulator_dev *rdev)
111 {
112 struct max8660 *max8660 = rdev_get_drvdata(rdev);
113 u8 val = max8660->shadow_regs[MAX8660_OVER1];
114 u8 mask = (rdev_get_id(rdev) == MAX8660_V3) ? 1 : 4;
115 return !!(val & mask);
116 }
117
118 static int max8660_dcdc_enable(struct regulator_dev *rdev)
119 {
120 struct max8660 *max8660 = rdev_get_drvdata(rdev);
121 u8 bit = (rdev_get_id(rdev) == MAX8660_V3) ? 1 : 4;
122 return max8660_write(max8660, MAX8660_OVER1, 0xff, bit);
123 }
124
125 static int max8660_dcdc_disable(struct regulator_dev *rdev)
126 {
127 struct max8660 *max8660 = rdev_get_drvdata(rdev);
128 u8 mask = (rdev_get_id(rdev) == MAX8660_V3) ? ~1 : ~4;
129 return max8660_write(max8660, MAX8660_OVER1, mask, 0);
130 }
131
132 static int max8660_dcdc_get_voltage_sel(struct regulator_dev *rdev)
133 {
134 struct max8660 *max8660 = rdev_get_drvdata(rdev);
135
136 u8 reg = (rdev_get_id(rdev) == MAX8660_V3) ? MAX8660_ADTV2 : MAX8660_SDTV2;
137 u8 selector = max8660->shadow_regs[reg];
138 return selector;
139 }
140
141 static int max8660_dcdc_set_voltage_sel(struct regulator_dev *rdev,
142 unsigned int selector)
143 {
144 struct max8660 *max8660 = rdev_get_drvdata(rdev);
145 u8 reg, bits;
146 int ret;
147
148 reg = (rdev_get_id(rdev) == MAX8660_V3) ? MAX8660_ADTV2 : MAX8660_SDTV2;
149 ret = max8660_write(max8660, reg, 0, selector);
150 if (ret)
151 return ret;
152
153 /* Select target voltage register and activate regulation */
154 bits = (rdev_get_id(rdev) == MAX8660_V3) ? 0x03 : 0x30;
155 return max8660_write(max8660, MAX8660_VCC1, 0xff, bits);
156 }
157
158 static struct regulator_ops max8660_dcdc_ops = {
159 .is_enabled = max8660_dcdc_is_enabled,
160 .list_voltage = regulator_list_voltage_linear,
161 .map_voltage = regulator_map_voltage_linear,
162 .set_voltage_sel = max8660_dcdc_set_voltage_sel,
163 .get_voltage_sel = max8660_dcdc_get_voltage_sel,
164 };
165
166
167 /*
168 * LDO5 functions
169 */
170
171 static int max8660_ldo5_get_voltage_sel(struct regulator_dev *rdev)
172 {
173 struct max8660 *max8660 = rdev_get_drvdata(rdev);
174
175 u8 selector = max8660->shadow_regs[MAX8660_MDTV2];
176 return selector;
177 }
178
179 static int max8660_ldo5_set_voltage_sel(struct regulator_dev *rdev,
180 unsigned int selector)
181 {
182 struct max8660 *max8660 = rdev_get_drvdata(rdev);
183 int ret;
184
185 ret = max8660_write(max8660, MAX8660_MDTV2, 0, selector);
186 if (ret)
187 return ret;
188
189 /* Select target voltage register and activate regulation */
190 return max8660_write(max8660, MAX8660_VCC1, 0xff, 0xc0);
191 }
192
193 static struct regulator_ops max8660_ldo5_ops = {
194 .list_voltage = regulator_list_voltage_linear,
195 .map_voltage = regulator_map_voltage_linear,
196 .set_voltage_sel = max8660_ldo5_set_voltage_sel,
197 .get_voltage_sel = max8660_ldo5_get_voltage_sel,
198 };
199
200
201 /*
202 * LDO67 functions
203 */
204
205 static int max8660_ldo67_is_enabled(struct regulator_dev *rdev)
206 {
207 struct max8660 *max8660 = rdev_get_drvdata(rdev);
208 u8 val = max8660->shadow_regs[MAX8660_OVER2];
209 u8 mask = (rdev_get_id(rdev) == MAX8660_V6) ? 2 : 4;
210 return !!(val & mask);
211 }
212
213 static int max8660_ldo67_enable(struct regulator_dev *rdev)
214 {
215 struct max8660 *max8660 = rdev_get_drvdata(rdev);
216 u8 bit = (rdev_get_id(rdev) == MAX8660_V6) ? 2 : 4;
217 return max8660_write(max8660, MAX8660_OVER2, 0xff, bit);
218 }
219
220 static int max8660_ldo67_disable(struct regulator_dev *rdev)
221 {
222 struct max8660 *max8660 = rdev_get_drvdata(rdev);
223 u8 mask = (rdev_get_id(rdev) == MAX8660_V6) ? ~2 : ~4;
224 return max8660_write(max8660, MAX8660_OVER2, mask, 0);
225 }
226
227 static int max8660_ldo67_get_voltage_sel(struct regulator_dev *rdev)
228 {
229 struct max8660 *max8660 = rdev_get_drvdata(rdev);
230
231 u8 shift = (rdev_get_id(rdev) == MAX8660_V6) ? 0 : 4;
232 u8 selector = (max8660->shadow_regs[MAX8660_L12VCR] >> shift) & 0xf;
233 return selector;
234 }
235
236 static int max8660_ldo67_set_voltage_sel(struct regulator_dev *rdev,
237 unsigned int selector)
238 {
239 struct max8660 *max8660 = rdev_get_drvdata(rdev);
240
241 if (rdev_get_id(rdev) == MAX8660_V6)
242 return max8660_write(max8660, MAX8660_L12VCR, 0xf0, selector);
243 else
244 return max8660_write(max8660, MAX8660_L12VCR, 0x0f,
245 selector << 4);
246 }
247
248 static struct regulator_ops max8660_ldo67_ops = {
249 .is_enabled = max8660_ldo67_is_enabled,
250 .enable = max8660_ldo67_enable,
251 .disable = max8660_ldo67_disable,
252 .list_voltage = regulator_list_voltage_linear,
253 .map_voltage = regulator_map_voltage_linear,
254 .get_voltage_sel = max8660_ldo67_get_voltage_sel,
255 .set_voltage_sel = max8660_ldo67_set_voltage_sel,
256 };
257
258 static const struct regulator_desc max8660_reg[] = {
259 {
260 .name = "V3(DCDC)",
261 .id = MAX8660_V3,
262 .ops = &max8660_dcdc_ops,
263 .type = REGULATOR_VOLTAGE,
264 .n_voltages = MAX8660_DCDC_MAX_SEL + 1,
265 .owner = THIS_MODULE,
266 .min_uV = MAX8660_DCDC_MIN_UV,
267 .uV_step = MAX8660_DCDC_STEP,
268 },
269 {
270 .name = "V4(DCDC)",
271 .id = MAX8660_V4,
272 .ops = &max8660_dcdc_ops,
273 .type = REGULATOR_VOLTAGE,
274 .n_voltages = MAX8660_DCDC_MAX_SEL + 1,
275 .owner = THIS_MODULE,
276 .min_uV = MAX8660_DCDC_MIN_UV,
277 .uV_step = MAX8660_DCDC_STEP,
278 },
279 {
280 .name = "V5(LDO)",
281 .id = MAX8660_V5,
282 .ops = &max8660_ldo5_ops,
283 .type = REGULATOR_VOLTAGE,
284 .n_voltages = MAX8660_LDO5_MAX_SEL + 1,
285 .owner = THIS_MODULE,
286 .min_uV = MAX8660_LDO5_MIN_UV,
287 .uV_step = MAX8660_LDO5_STEP,
288 },
289 {
290 .name = "V6(LDO)",
291 .id = MAX8660_V6,
292 .ops = &max8660_ldo67_ops,
293 .type = REGULATOR_VOLTAGE,
294 .n_voltages = MAX8660_LDO67_MAX_SEL + 1,
295 .owner = THIS_MODULE,
296 .min_uV = MAX8660_LDO67_MIN_UV,
297 .uV_step = MAX8660_LDO67_STEP,
298 },
299 {
300 .name = "V7(LDO)",
301 .id = MAX8660_V7,
302 .ops = &max8660_ldo67_ops,
303 .type = REGULATOR_VOLTAGE,
304 .n_voltages = MAX8660_LDO67_MAX_SEL + 1,
305 .owner = THIS_MODULE,
306 .min_uV = MAX8660_LDO67_MIN_UV,
307 .uV_step = MAX8660_LDO67_STEP,
308 },
309 };
310
311 enum {
312 MAX8660 = 0,
313 MAX8661 = 1,
314 };
315
316 #ifdef CONFIG_OF
317 static const struct of_device_id max8660_dt_ids[] = {
318 { .compatible = "maxim,max8660", .data = (void *) MAX8660 },
319 { .compatible = "maxim,max8661", .data = (void *) MAX8661 },
320 { }
321 };
322 MODULE_DEVICE_TABLE(of, max8660_dt_ids);
323
324 static int max8660_pdata_from_dt(struct device *dev,
325 struct device_node **of_node,
326 struct max8660_platform_data *pdata)
327 {
328 int matched, i;
329 struct device_node *np;
330 struct max8660_subdev_data *sub;
331 struct of_regulator_match rmatch[ARRAY_SIZE(max8660_reg)];
332
333 np = of_find_node_by_name(dev->of_node, "regulators");
334 if (!np) {
335 dev_err(dev, "missing 'regulators' subnode in DT\n");
336 return -EINVAL;
337 }
338
339 for (i = 0; i < ARRAY_SIZE(rmatch); i++)
340 rmatch[i].name = max8660_reg[i].name;
341
342 matched = of_regulator_match(dev, np, rmatch, ARRAY_SIZE(rmatch));
343 if (matched <= 0)
344 return matched;
345
346 pdata->subdevs = devm_kzalloc(dev, sizeof(struct max8660_subdev_data) *
347 matched, GFP_KERNEL);
348 if (!pdata->subdevs)
349 return -ENOMEM;
350
351 pdata->num_subdevs = matched;
352 sub = pdata->subdevs;
353
354 for (i = 0; i < matched; i++) {
355 sub->id = i;
356 sub->name = rmatch[i].name;
357 sub->platform_data = rmatch[i].init_data;
358 of_node[i] = rmatch[i].of_node;
359 sub++;
360 }
361
362 return 0;
363 }
364 #else
365 static inline int max8660_pdata_from_dt(struct device *dev,
366 struct device_node **of_node,
367 struct max8660_platform_data *pdata)
368 {
369 return 0;
370 }
371 #endif
372
373 static int max8660_probe(struct i2c_client *client,
374 const struct i2c_device_id *i2c_id)
375 {
376 struct regulator_dev **rdev;
377 struct device *dev = &client->dev;
378 struct max8660_platform_data *pdata = dev_get_platdata(dev);
379 struct regulator_config config = { };
380 struct max8660 *max8660;
381 int boot_on, i, id, ret = -EINVAL;
382 struct device_node *of_node[MAX8660_V_END];
383 unsigned long type;
384
385 if (dev->of_node && !pdata) {
386 const struct of_device_id *id;
387 struct max8660_platform_data pdata_of;
388
389 id = of_match_device(of_match_ptr(max8660_dt_ids), dev);
390 if (!id)
391 return -ENODEV;
392
393 ret = max8660_pdata_from_dt(dev, of_node, &pdata_of);
394 if (ret < 0)
395 return ret;
396
397 pdata = &pdata_of;
398 type = (unsigned long) id->data;
399 } else {
400 type = i2c_id->driver_data;
401 memset(of_node, 0, sizeof(of_node));
402 }
403
404 if (pdata->num_subdevs > MAX8660_V_END) {
405 dev_err(dev, "Too many regulators found!\n");
406 return -EINVAL;
407 }
408
409 max8660 = devm_kzalloc(dev, sizeof(struct max8660) +
410 sizeof(struct regulator_dev *) * MAX8660_V_END,
411 GFP_KERNEL);
412 if (!max8660)
413 return -ENOMEM;
414
415 max8660->client = client;
416 rdev = max8660->rdev;
417
418 if (pdata->en34_is_high) {
419 /* Simulate always on */
420 max8660->shadow_regs[MAX8660_OVER1] = 5;
421 } else {
422 /* Otherwise devices can be toggled via software */
423 max8660_dcdc_ops.enable = max8660_dcdc_enable;
424 max8660_dcdc_ops.disable = max8660_dcdc_disable;
425 }
426
427 /*
428 * First, set up shadow registers to prevent glitches. As some
429 * registers are shared between regulators, everything must be properly
430 * set up for all regulators in advance.
431 */
432 max8660->shadow_regs[MAX8660_ADTV1] =
433 max8660->shadow_regs[MAX8660_ADTV2] =
434 max8660->shadow_regs[MAX8660_SDTV1] =
435 max8660->shadow_regs[MAX8660_SDTV2] = 0x1b;
436 max8660->shadow_regs[MAX8660_MDTV1] =
437 max8660->shadow_regs[MAX8660_MDTV2] = 0x04;
438
439 for (i = 0; i < pdata->num_subdevs; i++) {
440
441 if (!pdata->subdevs[i].platform_data)
442 return ret;
443
444 boot_on = pdata->subdevs[i].platform_data->constraints.boot_on;
445
446 switch (pdata->subdevs[i].id) {
447 case MAX8660_V3:
448 if (boot_on)
449 max8660->shadow_regs[MAX8660_OVER1] |= 1;
450 break;
451
452 case MAX8660_V4:
453 if (boot_on)
454 max8660->shadow_regs[MAX8660_OVER1] |= 4;
455 break;
456
457 case MAX8660_V5:
458 break;
459
460 case MAX8660_V6:
461 if (boot_on)
462 max8660->shadow_regs[MAX8660_OVER2] |= 2;
463 break;
464
465 case MAX8660_V7:
466 if (type == MAX8661) {
467 dev_err(dev, "Regulator not on this chip!\n");
468 return -EINVAL;
469 }
470
471 if (boot_on)
472 max8660->shadow_regs[MAX8660_OVER2] |= 4;
473 break;
474
475 default:
476 dev_err(dev, "invalid regulator %s\n",
477 pdata->subdevs[i].name);
478 return ret;
479 }
480 }
481
482 /* Finally register devices */
483 for (i = 0; i < pdata->num_subdevs; i++) {
484
485 id = pdata->subdevs[i].id;
486
487 config.dev = dev;
488 config.init_data = pdata->subdevs[i].platform_data;
489 config.of_node = of_node[i];
490 config.driver_data = max8660;
491
492 rdev[i] = devm_regulator_register(&client->dev,
493 &max8660_reg[id], &config);
494 if (IS_ERR(rdev[i])) {
495 ret = PTR_ERR(rdev[i]);
496 dev_err(&client->dev, "failed to register %s\n",
497 max8660_reg[id].name);
498 return PTR_ERR(rdev[i]);
499 }
500 }
501
502 i2c_set_clientdata(client, max8660);
503 return 0;
504 }
505
506 static const struct i2c_device_id max8660_id[] = {
507 { .name = "max8660", .driver_data = MAX8660 },
508 { .name = "max8661", .driver_data = MAX8661 },
509 { }
510 };
511 MODULE_DEVICE_TABLE(i2c, max8660_id);
512
513 static struct i2c_driver max8660_driver = {
514 .probe = max8660_probe,
515 .driver = {
516 .name = "max8660",
517 .owner = THIS_MODULE,
518 },
519 .id_table = max8660_id,
520 };
521
522 static int __init max8660_init(void)
523 {
524 return i2c_add_driver(&max8660_driver);
525 }
526 subsys_initcall(max8660_init);
527
528 static void __exit max8660_exit(void)
529 {
530 i2c_del_driver(&max8660_driver);
531 }
532 module_exit(max8660_exit);
533
534 /* Module information */
535 MODULE_DESCRIPTION("MAXIM 8660/8661 voltage regulator driver");
536 MODULE_AUTHOR("Wolfram Sang");
537 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support