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x86/PCI: use host bridge _CRS info on ASUS M2V-MX SE
[linux-btrfs-devel.git] / drivers / regulator / max8660.c
blob33f5d9a492efa809b3177ce1034bef633c32c037
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
48 #define MAX8660_DCDC_MIN_UV 725000
49 #define MAX8660_DCDC_MAX_UV 1800000
50 #define MAX8660_DCDC_STEP 25000
51 #define MAX8660_DCDC_MAX_SEL 0x2b
52
53 #define MAX8660_LDO5_MIN_UV 1700000
54 #define MAX8660_LDO5_MAX_UV 2000000
55 #define MAX8660_LDO5_STEP 25000
56 #define MAX8660_LDO5_MAX_SEL 0x0c
57
58 #define MAX8660_LDO67_MIN_UV 1800000
59 #define MAX8660_LDO67_MAX_UV 3300000
60 #define MAX8660_LDO67_STEP 100000
61 #define MAX8660_LDO67_MAX_SEL 0x0f
62
63 enum {
64 MAX8660_OVER1,
65 MAX8660_OVER2,
66 MAX8660_VCC1,
67 MAX8660_ADTV1,
68 MAX8660_ADTV2,
69 MAX8660_SDTV1,
70 MAX8660_SDTV2,
71 MAX8660_MDTV1,
72 MAX8660_MDTV2,
73 MAX8660_L12VCR,
74 MAX8660_FPWM,
75 MAX8660_N_REGS, /* not a real register */
76 };
77
78 struct max8660 {
79 struct i2c_client *client;
80 u8 shadow_regs[MAX8660_N_REGS]; /* as chip is write only */
81 struct regulator_dev *rdev[];
82 };
83
84 static int max8660_write(struct max8660 *max8660, u8 reg, u8 mask, u8 val)
85 {
86 static const u8 max8660_addresses[MAX8660_N_REGS] =
87 { 0x10, 0x12, 0x20, 0x23, 0x24, 0x29, 0x2a, 0x32, 0x33, 0x39, 0x80 };
88
89 int ret;
90 u8 reg_val = (max8660->shadow_regs[reg] & mask) | val;
91 dev_vdbg(&max8660->client->dev, "Writing reg %02x with %02x\n",
92 max8660_addresses[reg], reg_val);
93
94 ret = i2c_smbus_write_byte_data(max8660->client,
95 max8660_addresses[reg], reg_val);
96 if (ret == 0)
97 max8660->shadow_regs[reg] = reg_val;
98
99 return ret;
100 }
101
102
103 /*
104 * DCDC functions
105 */
106
107 static int max8660_dcdc_is_enabled(struct regulator_dev *rdev)
108 {
109 struct max8660 *max8660 = rdev_get_drvdata(rdev);
110 u8 val = max8660->shadow_regs[MAX8660_OVER1];
111 u8 mask = (rdev_get_id(rdev) == MAX8660_V3) ? 1 : 4;
112 return !!(val & mask);
113 }
114
115 static int max8660_dcdc_enable(struct regulator_dev *rdev)
116 {
117 struct max8660 *max8660 = rdev_get_drvdata(rdev);
118 u8 bit = (rdev_get_id(rdev) == MAX8660_V3) ? 1 : 4;
119 return max8660_write(max8660, MAX8660_OVER1, 0xff, bit);
120 }
121
122 static int max8660_dcdc_disable(struct regulator_dev *rdev)
123 {
124 struct max8660 *max8660 = rdev_get_drvdata(rdev);
125 u8 mask = (rdev_get_id(rdev) == MAX8660_V3) ? ~1 : ~4;
126 return max8660_write(max8660, MAX8660_OVER1, mask, 0);
127 }
128
129 static int max8660_dcdc_list(struct regulator_dev *rdev, unsigned selector)
130 {
131 if (selector > MAX8660_DCDC_MAX_SEL)
132 return -EINVAL;
133 return MAX8660_DCDC_MIN_UV + selector * MAX8660_DCDC_STEP;
134 }
135
136 static int max8660_dcdc_get(struct regulator_dev *rdev)
137 {
138 struct max8660 *max8660 = rdev_get_drvdata(rdev);
139 u8 reg = (rdev_get_id(rdev) == MAX8660_V3) ? MAX8660_ADTV2 : MAX8660_SDTV2;
140 u8 selector = max8660->shadow_regs[reg];
141 return MAX8660_DCDC_MIN_UV + selector * MAX8660_DCDC_STEP;
142 }
143
144 static int max8660_dcdc_set(struct regulator_dev *rdev, int min_uV, int max_uV,
145 unsigned int *s)
146 {
147 struct max8660 *max8660 = rdev_get_drvdata(rdev);
148 u8 reg, selector, bits;
149 int ret;
150
151 if (min_uV < MAX8660_DCDC_MIN_UV || min_uV > MAX8660_DCDC_MAX_UV)
152 return -EINVAL;
153 if (max_uV < MAX8660_DCDC_MIN_UV || max_uV > MAX8660_DCDC_MAX_UV)
154 return -EINVAL;
155
156 selector = (min_uV - (MAX8660_DCDC_MIN_UV - MAX8660_DCDC_STEP + 1))
157 / MAX8660_DCDC_STEP;
158 *s = selector;
159
160 ret = max8660_dcdc_list(rdev, selector);
161 if (ret < 0 || ret > max_uV)
162 return -EINVAL;
163
164 reg = (rdev_get_id(rdev) == MAX8660_V3) ? MAX8660_ADTV2 : MAX8660_SDTV2;
165 ret = max8660_write(max8660, reg, 0, selector);
166 if (ret)
167 return ret;
168
169 /* Select target voltage register and activate regulation */
170 bits = (rdev_get_id(rdev) == MAX8660_V3) ? 0x03 : 0x30;
171 return max8660_write(max8660, MAX8660_VCC1, 0xff, bits);
172 }
173
174 static struct regulator_ops max8660_dcdc_ops = {
175 .is_enabled = max8660_dcdc_is_enabled,
176 .list_voltage = max8660_dcdc_list,
177 .set_voltage = max8660_dcdc_set,
178 .get_voltage = max8660_dcdc_get,
179 };
180
181
182 /*
183 * LDO5 functions
184 */
185
186 static int max8660_ldo5_list(struct regulator_dev *rdev, unsigned selector)
187 {
188 if (selector > MAX8660_LDO5_MAX_SEL)
189 return -EINVAL;
190 return MAX8660_LDO5_MIN_UV + selector * MAX8660_LDO5_STEP;
191 }
192
193 static int max8660_ldo5_get(struct regulator_dev *rdev)
194 {
195 struct max8660 *max8660 = rdev_get_drvdata(rdev);
196 u8 selector = max8660->shadow_regs[MAX8660_MDTV2];
197
198 return MAX8660_LDO5_MIN_UV + selector * MAX8660_LDO5_STEP;
199 }
200
201 static int max8660_ldo5_set(struct regulator_dev *rdev, int min_uV, int max_uV,
202 unsigned int *s)
203 {
204 struct max8660 *max8660 = rdev_get_drvdata(rdev);
205 u8 selector;
206 int ret;
207
208 if (min_uV < MAX8660_LDO5_MIN_UV || min_uV > MAX8660_LDO5_MAX_UV)
209 return -EINVAL;
210 if (max_uV < MAX8660_LDO5_MIN_UV || max_uV > MAX8660_LDO5_MAX_UV)
211 return -EINVAL;
212
213 selector = (min_uV - (MAX8660_LDO5_MIN_UV - MAX8660_LDO5_STEP + 1))
214 / MAX8660_LDO5_STEP;
215 ret = max8660_ldo5_list(rdev, selector);
216 if (ret < 0 || ret > max_uV)
217 return -EINVAL;
218
219 *s = selector;
220
221 ret = max8660_write(max8660, MAX8660_MDTV2, 0, selector);
222 if (ret)
223 return ret;
224
225 /* Select target voltage register and activate regulation */
226 return max8660_write(max8660, MAX8660_VCC1, 0xff, 0xc0);
227 }
228
229 static struct regulator_ops max8660_ldo5_ops = {
230 .list_voltage = max8660_ldo5_list,
231 .set_voltage = max8660_ldo5_set,
232 .get_voltage = max8660_ldo5_get,
233 };
234
235
236 /*
237 * LDO67 functions
238 */
239
240 static int max8660_ldo67_is_enabled(struct regulator_dev *rdev)
241 {
242 struct max8660 *max8660 = rdev_get_drvdata(rdev);
243 u8 val = max8660->shadow_regs[MAX8660_OVER2];
244 u8 mask = (rdev_get_id(rdev) == MAX8660_V6) ? 2 : 4;
245 return !!(val & mask);
246 }
247
248 static int max8660_ldo67_enable(struct regulator_dev *rdev)
249 {
250 struct max8660 *max8660 = rdev_get_drvdata(rdev);
251 u8 bit = (rdev_get_id(rdev) == MAX8660_V6) ? 2 : 4;
252 return max8660_write(max8660, MAX8660_OVER2, 0xff, bit);
253 }
254
255 static int max8660_ldo67_disable(struct regulator_dev *rdev)
256 {
257 struct max8660 *max8660 = rdev_get_drvdata(rdev);
258 u8 mask = (rdev_get_id(rdev) == MAX8660_V6) ? ~2 : ~4;
259 return max8660_write(max8660, MAX8660_OVER2, mask, 0);
260 }
261
262 static int max8660_ldo67_list(struct regulator_dev *rdev, unsigned selector)
263 {
264 if (selector > MAX8660_LDO67_MAX_SEL)
265 return -EINVAL;
266 return MAX8660_LDO67_MIN_UV + selector * MAX8660_LDO67_STEP;
267 }
268
269 static int max8660_ldo67_get(struct regulator_dev *rdev)
270 {
271 struct max8660 *max8660 = rdev_get_drvdata(rdev);
272 u8 shift = (rdev_get_id(rdev) == MAX8660_V6) ? 0 : 4;
273 u8 selector = (max8660->shadow_regs[MAX8660_L12VCR] >> shift) & 0xf;
274
275 return MAX8660_LDO67_MIN_UV + selector * MAX8660_LDO67_STEP;
276 }
277
278 static int max8660_ldo67_set(struct regulator_dev *rdev, int min_uV,
279 int max_uV, unsigned int *s)
280 {
281 struct max8660 *max8660 = rdev_get_drvdata(rdev);
282 u8 selector;
283 int ret;
284
285 if (min_uV < MAX8660_LDO67_MIN_UV || min_uV > MAX8660_LDO67_MAX_UV)
286 return -EINVAL;
287 if (max_uV < MAX8660_LDO67_MIN_UV || max_uV > MAX8660_LDO67_MAX_UV)
288 return -EINVAL;
289
290 selector = (min_uV - (MAX8660_LDO67_MIN_UV - MAX8660_LDO67_STEP + 1))
291 / MAX8660_LDO67_STEP;
292
293 ret = max8660_ldo67_list(rdev, selector);
294 if (ret < 0 || ret > max_uV)
295 return -EINVAL;
296
297 *s = selector;
298
299 if (rdev_get_id(rdev) == MAX8660_V6)
300 return max8660_write(max8660, MAX8660_L12VCR, 0xf0, selector);
301 else
302 return max8660_write(max8660, MAX8660_L12VCR, 0x0f, selector << 4);
303 }
304
305 static struct regulator_ops max8660_ldo67_ops = {
306 .is_enabled = max8660_ldo67_is_enabled,
307 .enable = max8660_ldo67_enable,
308 .disable = max8660_ldo67_disable,
309 .list_voltage = max8660_ldo67_list,
310 .get_voltage = max8660_ldo67_get,
311 .set_voltage = max8660_ldo67_set,
312 };
313
314 static struct regulator_desc max8660_reg[] = {
315 {
316 .name = "V3(DCDC)",
317 .id = MAX8660_V3,
318 .ops = &max8660_dcdc_ops,
319 .type = REGULATOR_VOLTAGE,
320 .n_voltages = MAX8660_DCDC_MAX_SEL + 1,
321 .owner = THIS_MODULE,
322 },
323 {
324 .name = "V4(DCDC)",
325 .id = MAX8660_V4,
326 .ops = &max8660_dcdc_ops,
327 .type = REGULATOR_VOLTAGE,
328 .n_voltages = MAX8660_DCDC_MAX_SEL + 1,
329 .owner = THIS_MODULE,
330 },
331 {
332 .name = "V5(LDO)",
333 .id = MAX8660_V5,
334 .ops = &max8660_ldo5_ops,
335 .type = REGULATOR_VOLTAGE,
336 .n_voltages = MAX8660_LDO5_MAX_SEL + 1,
337 .owner = THIS_MODULE,
338 },
339 {
340 .name = "V6(LDO)",
341 .id = MAX8660_V6,
342 .ops = &max8660_ldo67_ops,
343 .type = REGULATOR_VOLTAGE,
344 .n_voltages = MAX8660_LDO67_MAX_SEL + 1,
345 .owner = THIS_MODULE,
346 },
347 {
348 .name = "V7(LDO)",
349 .id = MAX8660_V7,
350 .ops = &max8660_ldo67_ops,
351 .type = REGULATOR_VOLTAGE,
352 .n_voltages = MAX8660_LDO67_MAX_SEL + 1,
353 .owner = THIS_MODULE,
354 },
355 };
356
357 static int __devinit max8660_probe(struct i2c_client *client,
358 const struct i2c_device_id *i2c_id)
359 {
360 struct regulator_dev **rdev;
361 struct max8660_platform_data *pdata = client->dev.platform_data;
362 struct max8660 *max8660;
363 int boot_on, i, id, ret = -EINVAL;
364
365 if (pdata->num_subdevs > MAX8660_V_END) {
366 dev_err(&client->dev, "Too many regulators found!\n");
367 goto out;
368 }
369
370 max8660 = kzalloc(sizeof(struct max8660) +
371 sizeof(struct regulator_dev *) * MAX8660_V_END,
372 GFP_KERNEL);
373 if (!max8660) {
374 ret = -ENOMEM;
375 goto out;
376 }
377
378 max8660->client = client;
379 rdev = max8660->rdev;
380
381 if (pdata->en34_is_high) {
382 /* Simulate always on */
383 max8660->shadow_regs[MAX8660_OVER1] = 5;
384 } else {
385 /* Otherwise devices can be toggled via software */
386 max8660_dcdc_ops.enable = max8660_dcdc_enable;
387 max8660_dcdc_ops.disable = max8660_dcdc_disable;
388 }
389
390 /*
391 * First, set up shadow registers to prevent glitches. As some
392 * registers are shared between regulators, everything must be properly
393 * set up for all regulators in advance.
394 */
395 max8660->shadow_regs[MAX8660_ADTV1] =
396 max8660->shadow_regs[MAX8660_ADTV2] =
397 max8660->shadow_regs[MAX8660_SDTV1] =
398 max8660->shadow_regs[MAX8660_SDTV2] = 0x1b;
399 max8660->shadow_regs[MAX8660_MDTV1] =
400 max8660->shadow_regs[MAX8660_MDTV2] = 0x04;
401
402 for (i = 0; i < pdata->num_subdevs; i++) {
403
404 if (!pdata->subdevs[i].platform_data)
405 goto err_free;
406
407 boot_on = pdata->subdevs[i].platform_data->constraints.boot_on;
408
409 switch (pdata->subdevs[i].id) {
410 case MAX8660_V3:
411 if (boot_on)
412 max8660->shadow_regs[MAX8660_OVER1] |= 1;
413 break;
414
415 case MAX8660_V4:
416 if (boot_on)
417 max8660->shadow_regs[MAX8660_OVER1] |= 4;
418 break;
419
420 case MAX8660_V5:
421 break;
422
423 case MAX8660_V6:
424 if (boot_on)
425 max8660->shadow_regs[MAX8660_OVER2] |= 2;
426 break;
427
428 case MAX8660_V7:
429 if (!strcmp(i2c_id->name, "max8661")) {
430 dev_err(&client->dev, "Regulator not on this chip!\n");
431 goto err_free;
432 }
433
434 if (boot_on)
435 max8660->shadow_regs[MAX8660_OVER2] |= 4;
436 break;
437
438 default:
439 dev_err(&client->dev, "invalid regulator %s\n",
440 pdata->subdevs[i].name);
441 goto err_free;
442 }
443 }
444
445 /* Finally register devices */
446 for (i = 0; i < pdata->num_subdevs; i++) {
447
448 id = pdata->subdevs[i].id;
449
450 rdev[i] = regulator_register(&max8660_reg[id], &client->dev,
451 pdata->subdevs[i].platform_data,
452 max8660);
453 if (IS_ERR(rdev[i])) {
454 ret = PTR_ERR(rdev[i]);
455 dev_err(&client->dev, "failed to register %s\n",
456 max8660_reg[id].name);
457 goto err_unregister;
458 }
459 }
460
461 i2c_set_clientdata(client, max8660);
462 dev_info(&client->dev, "Maxim 8660/8661 regulator driver loaded\n");
463 return 0;
464
465 err_unregister:
466 while (--i >= 0)
467 regulator_unregister(rdev[i]);
468 err_free:
469 kfree(max8660);
470 out:
471 return ret;
472 }
473
474 static int __devexit max8660_remove(struct i2c_client *client)
475 {
476 struct max8660 *max8660 = i2c_get_clientdata(client);
477 int i;
478
479 for (i = 0; i < MAX8660_V_END; i++)
480 if (max8660->rdev[i])
481 regulator_unregister(max8660->rdev[i]);
482 kfree(max8660);
483
484 return 0;
485 }
486
487 static const struct i2c_device_id max8660_id[] = {
488 { "max8660", 0 },
489 { "max8661", 0 },
490 { }
491 };
492 MODULE_DEVICE_TABLE(i2c, max8660_id);
493
494 static struct i2c_driver max8660_driver = {
495 .probe = max8660_probe,
496 .remove = __devexit_p(max8660_remove),
497 .driver = {
498 .name = "max8660",
499 .owner = THIS_MODULE,
500 },
501 .id_table = max8660_id,
502 };
503
504 static int __init max8660_init(void)
505 {
506 return i2c_add_driver(&max8660_driver);
507 }
508 subsys_initcall(max8660_init);
509
510 static void __exit max8660_exit(void)
511 {
512 i2c_del_driver(&max8660_driver);
513 }
514 module_exit(max8660_exit);
515
516 /* Module information */
517 MODULE_DESCRIPTION("MAXIM 8660/8661 voltage regulator driver");
518 MODULE_AUTHOR("Wolfram Sang");
519 MODULE_LICENSE("GPL v2");
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