1 /*
2  * wm831x-dcdc.c  --  DC-DC buck convertor driver for the WM831x series
3  *
4  * Copyright 2009 Wolfson Microelectronics PLC.
5  *
6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
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
10  *  Free Software Foundation;  either version 2 of the  License, or (at your
11  *  option) any later version.
12  */
13 
14 #include <linux/module.h>
15 #include <linux/moduleparam.h>
16 #include <linux/init.h>
17 #include <linux/bitops.h>
18 #include <linux/err.h>
19 #include <linux/i2c.h>
20 #include <linux/platform_device.h>
21 #include <linux/regulator/driver.h>
22 #include <linux/regulator/machine.h>
23 #include <linux/gpio.h>
24 #include <linux/slab.h>
25 
26 #include <linux/mfd/wm831x/core.h>
27 #include <linux/mfd/wm831x/regulator.h>
28 #include <linux/mfd/wm831x/pdata.h>
29 
30 #define WM831X_BUCKV_MAX_SELECTOR 0x68
31 #define WM831X_BUCKP_MAX_SELECTOR 0x66
32 
33 #define WM831X_DCDC_MODE_FAST    0
34 #define WM831X_DCDC_MODE_NORMAL  1
35 #define WM831X_DCDC_MODE_IDLE    2
36 #define WM831X_DCDC_MODE_STANDBY 3
37 
38 #define WM831X_DCDC_MAX_NAME 9
39 
40 /* Register offsets in control block */
41 #define WM831X_DCDC_CONTROL_1     0
42 #define WM831X_DCDC_CONTROL_2     1
43 #define WM831X_DCDC_ON_CONFIG     2
44 #define WM831X_DCDC_SLEEP_CONTROL 3
45 #define WM831X_DCDC_DVS_CONTROL   4
46 
47 /*
48  * Shared
49  */
50 
51 struct wm831x_dcdc {
52 	char name[WM831X_DCDC_MAX_NAME];
53 	char supply_name[WM831X_DCDC_MAX_NAME];
54 	struct regulator_desc desc;
55 	int base;
56 	struct wm831x *wm831x;
57 	struct regulator_dev *regulator;
58 	int dvs_gpio;
59 	int dvs_gpio_state;
60 	int on_vsel;
61 	int dvs_vsel;
62 };
63 
64 static unsigned int wm831x_dcdc_get_mode(struct regulator_dev *rdev)
65 
66 {
67 	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
68 	struct wm831x *wm831x = dcdc->wm831x;
69 	u16 reg = dcdc->base + WM831X_DCDC_ON_CONFIG;
70 	int val;
71 
72 	val = wm831x_reg_read(wm831x, reg);
73 	if (val < 0)
74 		return val;
75 
76 	val = (val & WM831X_DC1_ON_MODE_MASK) >> WM831X_DC1_ON_MODE_SHIFT;
77 
78 	switch (val) {
79 	case WM831X_DCDC_MODE_FAST:
80 		return REGULATOR_MODE_FAST;
81 	case WM831X_DCDC_MODE_NORMAL:
82 		return REGULATOR_MODE_NORMAL;
83 	case WM831X_DCDC_MODE_STANDBY:
84 		return REGULATOR_MODE_STANDBY;
85 	case WM831X_DCDC_MODE_IDLE:
86 		return REGULATOR_MODE_IDLE;
87 	default:
88 		BUG();
89 		return -EINVAL;
90 	}
91 }
92 
93 static int wm831x_dcdc_set_mode_int(struct wm831x *wm831x, int reg,
94 				    unsigned int mode)
95 {
96 	int val;
97 
98 	switch (mode) {
99 	case REGULATOR_MODE_FAST:
100 		val = WM831X_DCDC_MODE_FAST;
101 		break;
102 	case REGULATOR_MODE_NORMAL:
103 		val = WM831X_DCDC_MODE_NORMAL;
104 		break;
105 	case REGULATOR_MODE_STANDBY:
106 		val = WM831X_DCDC_MODE_STANDBY;
107 		break;
108 	case REGULATOR_MODE_IDLE:
109 		val = WM831X_DCDC_MODE_IDLE;
110 		break;
111 	default:
112 		return -EINVAL;
113 	}
114 
115 	return wm831x_set_bits(wm831x, reg, WM831X_DC1_ON_MODE_MASK,
116 			       val << WM831X_DC1_ON_MODE_SHIFT);
117 }
118 
119 static int wm831x_dcdc_set_mode(struct regulator_dev *rdev, unsigned int mode)
120 {
121 	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
122 	struct wm831x *wm831x = dcdc->wm831x;
123 	u16 reg = dcdc->base + WM831X_DCDC_ON_CONFIG;
124 
125 	return wm831x_dcdc_set_mode_int(wm831x, reg, mode);
126 }
127 
128 static int wm831x_dcdc_set_suspend_mode(struct regulator_dev *rdev,
129 					unsigned int mode)
130 {
131 	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
132 	struct wm831x *wm831x = dcdc->wm831x;
133 	u16 reg = dcdc->base + WM831X_DCDC_SLEEP_CONTROL;
134 
135 	return wm831x_dcdc_set_mode_int(wm831x, reg, mode);
136 }
137 
138 static int wm831x_dcdc_get_status(struct regulator_dev *rdev)
139 {
140 	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
141 	struct wm831x *wm831x = dcdc->wm831x;
142 	int ret;
143 
144 	/* First, check for errors */
145 	ret = wm831x_reg_read(wm831x, WM831X_DCDC_UV_STATUS);
146 	if (ret < 0)
147 		return ret;
148 
149 	if (ret & (1 << rdev_get_id(rdev))) {
150 		dev_dbg(wm831x->dev, "DCDC%d under voltage\n",
151 			rdev_get_id(rdev) + 1);
152 		return REGULATOR_STATUS_ERROR;
153 	}
154 
155 	/* DCDC1 and DCDC2 can additionally detect high voltage/current */
156 	if (rdev_get_id(rdev) < 2) {
157 		if (ret & (WM831X_DC1_OV_STS << rdev_get_id(rdev))) {
158 			dev_dbg(wm831x->dev, "DCDC%d over voltage\n",
159 				rdev_get_id(rdev) + 1);
160 			return REGULATOR_STATUS_ERROR;
161 		}
162 
163 		if (ret & (WM831X_DC1_HC_STS << rdev_get_id(rdev))) {
164 			dev_dbg(wm831x->dev, "DCDC%d over current\n",
165 				rdev_get_id(rdev) + 1);
166 			return REGULATOR_STATUS_ERROR;
167 		}
168 	}
169 
170 	/* Is the regulator on? */
171 	ret = wm831x_reg_read(wm831x, WM831X_DCDC_STATUS);
172 	if (ret < 0)
173 		return ret;
174 	if (!(ret & (1 << rdev_get_id(rdev))))
175 		return REGULATOR_STATUS_OFF;
176 
177 	/* TODO: When we handle hardware control modes so we can report the
178 	 * current mode. */
179 	return REGULATOR_STATUS_ON;
180 }
181 
182 static irqreturn_t wm831x_dcdc_uv_irq(int irq, void *data)
183 {
184 	struct wm831x_dcdc *dcdc = data;
185 
186 	regulator_notifier_call_chain(dcdc->regulator,
187 				      REGULATOR_EVENT_UNDER_VOLTAGE,
188 				      NULL);
189 
190 	return IRQ_HANDLED;
191 }
192 
193 static irqreturn_t wm831x_dcdc_oc_irq(int irq, void *data)
194 {
195 	struct wm831x_dcdc *dcdc = data;
196 
197 	regulator_notifier_call_chain(dcdc->regulator,
198 				      REGULATOR_EVENT_OVER_CURRENT,
199 				      NULL);
200 
201 	return IRQ_HANDLED;
202 }
203 
204 /*
205  * BUCKV specifics
206  */
207 
208 static int wm831x_buckv_list_voltage(struct regulator_dev *rdev,
209 				      unsigned selector)
210 {
211 	if (selector <= 0x8)
212 		return 600000;
213 	if (selector <= WM831X_BUCKV_MAX_SELECTOR)
214 		return 600000 + ((selector - 0x8) * 12500);
215 	return -EINVAL;
216 }
217 
218 static int wm831x_buckv_map_voltage(struct regulator_dev *rdev,
219 				   int min_uV, int max_uV)
220 {
221 	u16 vsel;
222 
223 	if (min_uV < 600000)
224 		vsel = 0;
225 	else if (min_uV <= 1800000)
226 		vsel = DIV_ROUND_UP(min_uV - 600000, 12500) + 8;
227 	else
228 		return -EINVAL;
229 
230 	if (wm831x_buckv_list_voltage(rdev, vsel) > max_uV)
231 		return -EINVAL;
232 
233 	return vsel;
234 }
235 
236 static int wm831x_buckv_set_dvs(struct regulator_dev *rdev, int state)
237 {
238 	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
239 
240 	if (state == dcdc->dvs_gpio_state)
241 		return 0;
242 
243 	dcdc->dvs_gpio_state = state;
244 	gpio_set_value(dcdc->dvs_gpio, state);
245 
246 	/* Should wait for DVS state change to be asserted if we have
247 	 * a GPIO for it, for now assume the device is configured
248 	 * for the fastest possible transition.
249 	 */
250 
251 	return 0;
252 }
253 
254 static int wm831x_buckv_set_voltage_sel(struct regulator_dev *rdev,
255 					unsigned vsel)
256 {
257 	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
258 	struct wm831x *wm831x = dcdc->wm831x;
259 	int on_reg = dcdc->base + WM831X_DCDC_ON_CONFIG;
260 	int dvs_reg = dcdc->base + WM831X_DCDC_DVS_CONTROL;
261 	int ret;
262 
263 	/* If this value is already set then do a GPIO update if we can */
264 	if (dcdc->dvs_gpio && dcdc->on_vsel == vsel)
265 		return wm831x_buckv_set_dvs(rdev, 0);
266 
267 	if (dcdc->dvs_gpio && dcdc->dvs_vsel == vsel)
268 		return wm831x_buckv_set_dvs(rdev, 1);
269 
270 	/* Always set the ON status to the minimum voltage */
271 	ret = wm831x_set_bits(wm831x, on_reg, WM831X_DC1_ON_VSEL_MASK, vsel);
272 	if (ret < 0)
273 		return ret;
274 	dcdc->on_vsel = vsel;
275 
276 	if (!dcdc->dvs_gpio)
277 		return ret;
278 
279 	/* Kick the voltage transition now */
280 	ret = wm831x_buckv_set_dvs(rdev, 0);
281 	if (ret < 0)
282 		return ret;
283 
284 	/*
285 	 * If this VSEL is higher than the last one we've seen then
286 	 * remember it as the DVS VSEL.  This is optimised for CPUfreq
287 	 * usage where we want to get to the highest voltage very
288 	 * quickly.
289 	 */
290 	if (vsel > dcdc->dvs_vsel) {
291 		ret = wm831x_set_bits(wm831x, dvs_reg,
292 				      WM831X_DC1_DVS_VSEL_MASK,
293 				      vsel);
294 		if (ret == 0)
295 			dcdc->dvs_vsel = vsel;
296 		else
297 			dev_warn(wm831x->dev,
298 				 "Failed to set DCDC DVS VSEL: %d\n", ret);
299 	}
300 
301 	return 0;
302 }
303 
304 static int wm831x_buckv_set_suspend_voltage(struct regulator_dev *rdev,
305 					    int uV)
306 {
307 	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
308 	struct wm831x *wm831x = dcdc->wm831x;
309 	u16 reg = dcdc->base + WM831X_DCDC_SLEEP_CONTROL;
310 	int vsel;
311 
312 	vsel = wm831x_buckv_map_voltage(rdev, uV, uV);
313 	if (vsel < 0)
314 		return vsel;
315 
316 	return wm831x_set_bits(wm831x, reg, WM831X_DC1_SLP_VSEL_MASK, vsel);
317 }
318 
319 static int wm831x_buckv_get_voltage_sel(struct regulator_dev *rdev)
320 {
321 	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
322 
323 	if (dcdc->dvs_gpio && dcdc->dvs_gpio_state)
324 		return dcdc->dvs_vsel;
325 	else
326 		return dcdc->on_vsel;
327 }
328 
329 /* Current limit options */
330 static u16 wm831x_dcdc_ilim[] = {
331 	125, 250, 375, 500, 625, 750, 875, 1000
332 };
333 
334 static int wm831x_buckv_set_current_limit(struct regulator_dev *rdev,
335 					   int min_uA, int max_uA)
336 {
337 	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
338 	struct wm831x *wm831x = dcdc->wm831x;
339 	u16 reg = dcdc->base + WM831X_DCDC_CONTROL_2;
340 	int i;
341 
342 	for (i = ARRAY_SIZE(wm831x_dcdc_ilim) - 1; i >= 0; i--) {
343 		if ((min_uA <= wm831x_dcdc_ilim[i]) &&
344 		    (wm831x_dcdc_ilim[i] <= max_uA))
345 			return wm831x_set_bits(wm831x, reg,
346 					       WM831X_DC1_HC_THR_MASK,
347 						i << WM831X_DC1_HC_THR_SHIFT);
348 	}
349 
350 	return -EINVAL;
351 }
352 
353 static int wm831x_buckv_get_current_limit(struct regulator_dev *rdev)
354 {
355 	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
356 	struct wm831x *wm831x = dcdc->wm831x;
357 	u16 reg = dcdc->base + WM831X_DCDC_CONTROL_2;
358 	int val;
359 
360 	val = wm831x_reg_read(wm831x, reg);
361 	if (val < 0)
362 		return val;
363 
364 	val = (val & WM831X_DC1_HC_THR_MASK) >> WM831X_DC1_HC_THR_SHIFT;
365 	return wm831x_dcdc_ilim[val];
366 }
367 
368 static struct regulator_ops wm831x_buckv_ops = {
369 	.set_voltage_sel = wm831x_buckv_set_voltage_sel,
370 	.get_voltage_sel = wm831x_buckv_get_voltage_sel,
371 	.list_voltage = wm831x_buckv_list_voltage,
372 	.map_voltage = wm831x_buckv_map_voltage,
373 	.set_suspend_voltage = wm831x_buckv_set_suspend_voltage,
374 	.set_current_limit = wm831x_buckv_set_current_limit,
375 	.get_current_limit = wm831x_buckv_get_current_limit,
376 
377 	.is_enabled = regulator_is_enabled_regmap,
378 	.enable = regulator_enable_regmap,
379 	.disable = regulator_disable_regmap,
380 	.get_status = wm831x_dcdc_get_status,
381 	.get_mode = wm831x_dcdc_get_mode,
382 	.set_mode = wm831x_dcdc_set_mode,
383 	.set_suspend_mode = wm831x_dcdc_set_suspend_mode,
384 };
385 
386 /*
387  * Set up DVS control.  We just log errors since we can still run
388  * (with reduced performance) if we fail.
389  */
390 static void wm831x_buckv_dvs_init(struct wm831x_dcdc *dcdc,
391 					    struct wm831x_buckv_pdata *pdata)
392 {
393 	struct wm831x *wm831x = dcdc->wm831x;
394 	int ret;
395 	u16 ctrl;
396 
397 	if (!pdata || !pdata->dvs_gpio)
398 		return;
399 
400 	/* gpiolib won't let us read the GPIO status so pick the higher
401 	 * of the two existing voltages so we take it as platform data.
402 	 */
403 	dcdc->dvs_gpio_state = pdata->dvs_init_state;
404 
405 	ret = gpio_request_one(pdata->dvs_gpio,
406 			       dcdc->dvs_gpio_state ? GPIOF_INIT_HIGH : 0,
407 			       "DCDC DVS");
408 	if (ret < 0) {
409 		dev_err(wm831x->dev, "Failed to get %s DVS GPIO: %d\n",
410 			dcdc->name, ret);
411 		return;
412 	}
413 
414 	dcdc->dvs_gpio = pdata->dvs_gpio;
415 
416 	switch (pdata->dvs_control_src) {
417 	case 1:
418 		ctrl = 2 << WM831X_DC1_DVS_SRC_SHIFT;
419 		break;
420 	case 2:
421 		ctrl = 3 << WM831X_DC1_DVS_SRC_SHIFT;
422 		break;
423 	default:
424 		dev_err(wm831x->dev, "Invalid DVS control source %d for %s\n",
425 			pdata->dvs_control_src, dcdc->name);
426 		return;
427 	}
428 
429 	/* If DVS_VSEL is set to the minimum value then raise it to ON_VSEL
430 	 * to make bootstrapping a bit smoother.
431 	 */
432 	if (!dcdc->dvs_vsel) {
433 		ret = wm831x_set_bits(wm831x,
434 				      dcdc->base + WM831X_DCDC_DVS_CONTROL,
435 				      WM831X_DC1_DVS_VSEL_MASK, dcdc->on_vsel);
436 		if (ret == 0)
437 			dcdc->dvs_vsel = dcdc->on_vsel;
438 		else
439 			dev_warn(wm831x->dev, "Failed to set DVS_VSEL: %d\n",
440 				 ret);
441 	}
442 
443 	ret = wm831x_set_bits(wm831x, dcdc->base + WM831X_DCDC_DVS_CONTROL,
444 			      WM831X_DC1_DVS_SRC_MASK, ctrl);
445 	if (ret < 0) {
446 		dev_err(wm831x->dev, "Failed to set %s DVS source: %d\n",
447 			dcdc->name, ret);
448 	}
449 }
450 
451 static int wm831x_buckv_probe(struct platform_device *pdev)
452 {
453 	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
454 	struct wm831x_pdata *pdata = dev_get_platdata(wm831x->dev);
455 	struct regulator_config config = { };
456 	int id;
457 	struct wm831x_dcdc *dcdc;
458 	struct resource *res;
459 	int ret, irq;
460 
461 	if (pdata && pdata->wm831x_num)
462 		id = (pdata->wm831x_num * 10) + 1;
463 	else
464 		id = 0;
465 	id = pdev->id - id;
466 
467 	dev_dbg(&pdev->dev, "Probing DCDC%d\n", id + 1);
468 
469 	dcdc = devm_kzalloc(&pdev->dev,  sizeof(struct wm831x_dcdc),
470 			    GFP_KERNEL);
471 	if (dcdc == NULL) {
472 		dev_err(&pdev->dev, "Unable to allocate private data\n");
473 		return -ENOMEM;
474 	}
475 
476 	dcdc->wm831x = wm831x;
477 
478 	res = platform_get_resource(pdev, IORESOURCE_REG, 0);
479 	if (res == NULL) {
480 		dev_err(&pdev->dev, "No REG resource\n");
481 		ret = -EINVAL;
482 		goto err;
483 	}
484 	dcdc->base = res->start;
485 
486 	snprintf(dcdc->name, sizeof(dcdc->name), "DCDC%d", id + 1);
487 	dcdc->desc.name = dcdc->name;
488 
489 	snprintf(dcdc->supply_name, sizeof(dcdc->supply_name),
490 		 "DC%dVDD", id + 1);
491 	dcdc->desc.supply_name = dcdc->supply_name;
492 
493 	dcdc->desc.id = id;
494 	dcdc->desc.type = REGULATOR_VOLTAGE;
495 	dcdc->desc.n_voltages = WM831X_BUCKV_MAX_SELECTOR + 1;
496 	dcdc->desc.ops = &wm831x_buckv_ops;
497 	dcdc->desc.owner = THIS_MODULE;
498 	dcdc->desc.enable_reg = WM831X_DCDC_ENABLE;
499 	dcdc->desc.enable_mask = 1 << id;
500 
501 	ret = wm831x_reg_read(wm831x, dcdc->base + WM831X_DCDC_ON_CONFIG);
502 	if (ret < 0) {
503 		dev_err(wm831x->dev, "Failed to read ON VSEL: %d\n", ret);
504 		goto err;
505 	}
506 	dcdc->on_vsel = ret & WM831X_DC1_ON_VSEL_MASK;
507 
508 	ret = wm831x_reg_read(wm831x, dcdc->base + WM831X_DCDC_DVS_CONTROL);
509 	if (ret < 0) {
510 		dev_err(wm831x->dev, "Failed to read DVS VSEL: %d\n", ret);
511 		goto err;
512 	}
513 	dcdc->dvs_vsel = ret & WM831X_DC1_DVS_VSEL_MASK;
514 
515 	if (pdata && pdata->dcdc[id])
516 		wm831x_buckv_dvs_init(dcdc, pdata->dcdc[id]->driver_data);
517 
518 	config.dev = pdev->dev.parent;
519 	if (pdata)
520 		config.init_data = pdata->dcdc[id];
521 	config.driver_data = dcdc;
522 	config.regmap = wm831x->regmap;
523 
524 	dcdc->regulator = regulator_register(&dcdc->desc, &config);
525 	if (IS_ERR(dcdc->regulator)) {
526 		ret = PTR_ERR(dcdc->regulator);
527 		dev_err(wm831x->dev, "Failed to register DCDC%d: %d\n",
528 			id + 1, ret);
529 		goto err;
530 	}
531 
532 	irq = wm831x_irq(wm831x, platform_get_irq_byname(pdev, "UV"));
533 	ret = request_threaded_irq(irq, NULL, wm831x_dcdc_uv_irq,
534 				   IRQF_TRIGGER_RISING, dcdc->name, dcdc);
535 	if (ret != 0) {
536 		dev_err(&pdev->dev, "Failed to request UV IRQ %d: %d\n",
537 			irq, ret);
538 		goto err_regulator;
539 	}
540 
541 	irq = wm831x_irq(wm831x, platform_get_irq_byname(pdev, "HC"));
542 	ret = request_threaded_irq(irq, NULL, wm831x_dcdc_oc_irq,
543 				   IRQF_TRIGGER_RISING, dcdc->name, dcdc);
544 	if (ret != 0) {
545 		dev_err(&pdev->dev, "Failed to request HC IRQ %d: %d\n",
546 			irq, ret);
547 		goto err_uv;
548 	}
549 
550 	platform_set_drvdata(pdev, dcdc);
551 
552 	return 0;
553 
554 err_uv:
555 	free_irq(wm831x_irq(wm831x, platform_get_irq_byname(pdev, "UV")),
556 		 dcdc);
557 err_regulator:
558 	regulator_unregister(dcdc->regulator);
559 err:
560 	if (dcdc->dvs_gpio)
561 		gpio_free(dcdc->dvs_gpio);
562 	return ret;
563 }
564 
565 static int wm831x_buckv_remove(struct platform_device *pdev)
566 {
567 	struct wm831x_dcdc *dcdc = platform_get_drvdata(pdev);
568 	struct wm831x *wm831x = dcdc->wm831x;
569 
570 	free_irq(wm831x_irq(wm831x, platform_get_irq_byname(pdev, "HC")),
571 			    dcdc);
572 	free_irq(wm831x_irq(wm831x, platform_get_irq_byname(pdev, "UV")),
573 			    dcdc);
574 	regulator_unregister(dcdc->regulator);
575 	if (dcdc->dvs_gpio)
576 		gpio_free(dcdc->dvs_gpio);
577 
578 	return 0;
579 }
580 
581 static struct platform_driver wm831x_buckv_driver = {
582 	.probe = wm831x_buckv_probe,
583 	.remove = wm831x_buckv_remove,
584 	.driver		= {
585 		.name	= "wm831x-buckv",
586 		.owner	= THIS_MODULE,
587 	},
588 };
589 
590 /*
591  * BUCKP specifics
592  */
593 
594 static int wm831x_buckp_set_suspend_voltage(struct regulator_dev *rdev, int uV)
595 {
596 	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
597 	struct wm831x *wm831x = dcdc->wm831x;
598 	u16 reg = dcdc->base + WM831X_DCDC_SLEEP_CONTROL;
599 	int sel;
600 
601 	sel = regulator_map_voltage_linear(rdev, uV, uV);
602 	if (sel < 0)
603 		return sel;
604 
605 	return wm831x_set_bits(wm831x, reg, WM831X_DC3_ON_VSEL_MASK, sel);
606 }
607 
608 static struct regulator_ops wm831x_buckp_ops = {
609 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
610 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
611 	.list_voltage = regulator_list_voltage_linear,
612 	.map_voltage = regulator_map_voltage_linear,
613 	.set_suspend_voltage = wm831x_buckp_set_suspend_voltage,
614 
615 	.is_enabled = regulator_is_enabled_regmap,
616 	.enable = regulator_enable_regmap,
617 	.disable = regulator_disable_regmap,
618 	.get_status = wm831x_dcdc_get_status,
619 	.get_mode = wm831x_dcdc_get_mode,
620 	.set_mode = wm831x_dcdc_set_mode,
621 	.set_suspend_mode = wm831x_dcdc_set_suspend_mode,
622 };
623 
624 static int wm831x_buckp_probe(struct platform_device *pdev)
625 {
626 	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
627 	struct wm831x_pdata *pdata = dev_get_platdata(wm831x->dev);
628 	struct regulator_config config = { };
629 	int id;
630 	struct wm831x_dcdc *dcdc;
631 	struct resource *res;
632 	int ret, irq;
633 
634 	if (pdata && pdata->wm831x_num)
635 		id = (pdata->wm831x_num * 10) + 1;
636 	else
637 		id = 0;
638 	id = pdev->id - id;
639 
640 	dev_dbg(&pdev->dev, "Probing DCDC%d\n", id + 1);
641 
642 	dcdc = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_dcdc),
643 			    GFP_KERNEL);
644 	if (dcdc == NULL) {
645 		dev_err(&pdev->dev, "Unable to allocate private data\n");
646 		return -ENOMEM;
647 	}
648 
649 	dcdc->wm831x = wm831x;
650 
651 	res = platform_get_resource(pdev, IORESOURCE_REG, 0);
652 	if (res == NULL) {
653 		dev_err(&pdev->dev, "No REG resource\n");
654 		ret = -EINVAL;
655 		goto err;
656 	}
657 	dcdc->base = res->start;
658 
659 	snprintf(dcdc->name, sizeof(dcdc->name), "DCDC%d", id + 1);
660 	dcdc->desc.name = dcdc->name;
661 
662 	snprintf(dcdc->supply_name, sizeof(dcdc->supply_name),
663 		 "DC%dVDD", id + 1);
664 	dcdc->desc.supply_name = dcdc->supply_name;
665 
666 	dcdc->desc.id = id;
667 	dcdc->desc.type = REGULATOR_VOLTAGE;
668 	dcdc->desc.n_voltages = WM831X_BUCKP_MAX_SELECTOR + 1;
669 	dcdc->desc.ops = &wm831x_buckp_ops;
670 	dcdc->desc.owner = THIS_MODULE;
671 	dcdc->desc.vsel_reg = dcdc->base + WM831X_DCDC_ON_CONFIG;
672 	dcdc->desc.vsel_mask = WM831X_DC3_ON_VSEL_MASK;
673 	dcdc->desc.enable_reg = WM831X_DCDC_ENABLE;
674 	dcdc->desc.enable_mask = 1 << id;
675 	dcdc->desc.min_uV = 850000;
676 	dcdc->desc.uV_step = 25000;
677 
678 	config.dev = pdev->dev.parent;
679 	if (pdata)
680 		config.init_data = pdata->dcdc[id];
681 	config.driver_data = dcdc;
682 	config.regmap = wm831x->regmap;
683 
684 	dcdc->regulator = regulator_register(&dcdc->desc, &config);
685 	if (IS_ERR(dcdc->regulator)) {
686 		ret = PTR_ERR(dcdc->regulator);
687 		dev_err(wm831x->dev, "Failed to register DCDC%d: %d\n",
688 			id + 1, ret);
689 		goto err;
690 	}
691 
692 	irq = wm831x_irq(wm831x, platform_get_irq_byname(pdev, "UV"));
693 	ret = request_threaded_irq(irq, NULL, wm831x_dcdc_uv_irq,
694 				   IRQF_TRIGGER_RISING,	dcdc->name, dcdc);
695 	if (ret != 0) {
696 		dev_err(&pdev->dev, "Failed to request UV IRQ %d: %d\n",
697 			irq, ret);
698 		goto err_regulator;
699 	}
700 
701 	platform_set_drvdata(pdev, dcdc);
702 
703 	return 0;
704 
705 err_regulator:
706 	regulator_unregister(dcdc->regulator);
707 err:
708 	return ret;
709 }
710 
711 static int wm831x_buckp_remove(struct platform_device *pdev)
712 {
713 	struct wm831x_dcdc *dcdc = platform_get_drvdata(pdev);
714 
715 	free_irq(wm831x_irq(dcdc->wm831x, platform_get_irq_byname(pdev, "UV")),
716 			    dcdc);
717 	regulator_unregister(dcdc->regulator);
718 
719 	return 0;
720 }
721 
722 static struct platform_driver wm831x_buckp_driver = {
723 	.probe = wm831x_buckp_probe,
724 	.remove = wm831x_buckp_remove,
725 	.driver		= {
726 		.name	= "wm831x-buckp",
727 		.owner	= THIS_MODULE,
728 	},
729 };
730 
731 /*
732  * DCDC boost convertors
733  */
734 
735 static int wm831x_boostp_get_status(struct regulator_dev *rdev)
736 {
737 	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
738 	struct wm831x *wm831x = dcdc->wm831x;
739 	int ret;
740 
741 	/* First, check for errors */
742 	ret = wm831x_reg_read(wm831x, WM831X_DCDC_UV_STATUS);
743 	if (ret < 0)
744 		return ret;
745 
746 	if (ret & (1 << rdev_get_id(rdev))) {
747 		dev_dbg(wm831x->dev, "DCDC%d under voltage\n",
748 			rdev_get_id(rdev) + 1);
749 		return REGULATOR_STATUS_ERROR;
750 	}
751 
752 	/* Is the regulator on? */
753 	ret = wm831x_reg_read(wm831x, WM831X_DCDC_STATUS);
754 	if (ret < 0)
755 		return ret;
756 	if (ret & (1 << rdev_get_id(rdev)))
757 		return REGULATOR_STATUS_ON;
758 	else
759 		return REGULATOR_STATUS_OFF;
760 }
761 
762 static struct regulator_ops wm831x_boostp_ops = {
763 	.get_status = wm831x_boostp_get_status,
764 
765 	.is_enabled = regulator_is_enabled_regmap,
766 	.enable = regulator_enable_regmap,
767 	.disable = regulator_disable_regmap,
768 };
769 
770 static int wm831x_boostp_probe(struct platform_device *pdev)
771 {
772 	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
773 	struct wm831x_pdata *pdata = dev_get_platdata(wm831x->dev);
774 	struct regulator_config config = { };
775 	int id = pdev->id % ARRAY_SIZE(pdata->dcdc);
776 	struct wm831x_dcdc *dcdc;
777 	struct resource *res;
778 	int ret, irq;
779 
780 	dev_dbg(&pdev->dev, "Probing DCDC%d\n", id + 1);
781 
782 	if (pdata == NULL || pdata->dcdc[id] == NULL)
783 		return -ENODEV;
784 
785 	dcdc = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_dcdc), GFP_KERNEL);
786 	if (dcdc == NULL) {
787 		dev_err(&pdev->dev, "Unable to allocate private data\n");
788 		return -ENOMEM;
789 	}
790 
791 	dcdc->wm831x = wm831x;
792 
793 	res = platform_get_resource(pdev, IORESOURCE_REG, 0);
794 	if (res == NULL) {
795 		dev_err(&pdev->dev, "No REG resource\n");
796 		ret = -EINVAL;
797 		goto err;
798 	}
799 	dcdc->base = res->start;
800 
801 	snprintf(dcdc->name, sizeof(dcdc->name), "DCDC%d", id + 1);
802 	dcdc->desc.name = dcdc->name;
803 	dcdc->desc.id = id;
804 	dcdc->desc.type = REGULATOR_VOLTAGE;
805 	dcdc->desc.ops = &wm831x_boostp_ops;
806 	dcdc->desc.owner = THIS_MODULE;
807 	dcdc->desc.enable_reg = WM831X_DCDC_ENABLE;
808 	dcdc->desc.enable_mask = 1 << id;
809 
810 	config.dev = pdev->dev.parent;
811 	if (pdata)
812 		config.init_data = pdata->dcdc[id];
813 	config.driver_data = dcdc;
814 	config.regmap = wm831x->regmap;
815 
816 	dcdc->regulator = regulator_register(&dcdc->desc, &config);
817 	if (IS_ERR(dcdc->regulator)) {
818 		ret = PTR_ERR(dcdc->regulator);
819 		dev_err(wm831x->dev, "Failed to register DCDC%d: %d\n",
820 			id + 1, ret);
821 		goto err;
822 	}
823 
824 	irq = wm831x_irq(wm831x, platform_get_irq_byname(pdev, "UV"));
825 	ret = request_threaded_irq(irq, NULL, wm831x_dcdc_uv_irq,
826 				   IRQF_TRIGGER_RISING, dcdc->name,
827 				   dcdc);
828 	if (ret != 0) {
829 		dev_err(&pdev->dev, "Failed to request UV IRQ %d: %d\n",
830 			irq, ret);
831 		goto err_regulator;
832 	}
833 
834 	platform_set_drvdata(pdev, dcdc);
835 
836 	return 0;
837 
838 err_regulator:
839 	regulator_unregister(dcdc->regulator);
840 err:
841 	return ret;
842 }
843 
844 static int wm831x_boostp_remove(struct platform_device *pdev)
845 {
846 	struct wm831x_dcdc *dcdc = platform_get_drvdata(pdev);
847 
848 	free_irq(wm831x_irq(dcdc->wm831x, platform_get_irq_byname(pdev, "UV")),
849 		 dcdc);
850 	regulator_unregister(dcdc->regulator);
851 
852 	return 0;
853 }
854 
855 static struct platform_driver wm831x_boostp_driver = {
856 	.probe = wm831x_boostp_probe,
857 	.remove = wm831x_boostp_remove,
858 	.driver		= {
859 		.name	= "wm831x-boostp",
860 		.owner	= THIS_MODULE,
861 	},
862 };
863 
864 /*
865  * External Power Enable
866  *
867  * These aren't actually DCDCs but look like them in hardware so share
868  * code.
869  */
870 
871 #define WM831X_EPE_BASE 6
872 
873 static struct regulator_ops wm831x_epe_ops = {
874 	.is_enabled = regulator_is_enabled_regmap,
875 	.enable = regulator_enable_regmap,
876 	.disable = regulator_disable_regmap,
877 	.get_status = wm831x_dcdc_get_status,
878 };
879 
880 static int wm831x_epe_probe(struct platform_device *pdev)
881 {
882 	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
883 	struct wm831x_pdata *pdata = dev_get_platdata(wm831x->dev);
884 	struct regulator_config config = { };
885 	int id = pdev->id % ARRAY_SIZE(pdata->epe);
886 	struct wm831x_dcdc *dcdc;
887 	int ret;
888 
889 	dev_dbg(&pdev->dev, "Probing EPE%d\n", id + 1);
890 
891 	dcdc = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_dcdc), GFP_KERNEL);
892 	if (dcdc == NULL) {
893 		dev_err(&pdev->dev, "Unable to allocate private data\n");
894 		return -ENOMEM;
895 	}
896 
897 	dcdc->wm831x = wm831x;
898 
899 	/* For current parts this is correct; probably need to revisit
900 	 * in future.
901 	 */
902 	snprintf(dcdc->name, sizeof(dcdc->name), "EPE%d", id + 1);
903 	dcdc->desc.name = dcdc->name;
904 	dcdc->desc.id = id + WM831X_EPE_BASE; /* Offset in DCDC registers */
905 	dcdc->desc.ops = &wm831x_epe_ops;
906 	dcdc->desc.type = REGULATOR_VOLTAGE;
907 	dcdc->desc.owner = THIS_MODULE;
908 	dcdc->desc.enable_reg = WM831X_DCDC_ENABLE;
909 	dcdc->desc.enable_mask = 1 << dcdc->desc.id;
910 
911 	config.dev = pdev->dev.parent;
912 	if (pdata)
913 		config.init_data = pdata->epe[id];
914 	config.driver_data = dcdc;
915 	config.regmap = wm831x->regmap;
916 
917 	dcdc->regulator = regulator_register(&dcdc->desc, &config);
918 	if (IS_ERR(dcdc->regulator)) {
919 		ret = PTR_ERR(dcdc->regulator);
920 		dev_err(wm831x->dev, "Failed to register EPE%d: %d\n",
921 			id + 1, ret);
922 		goto err;
923 	}
924 
925 	platform_set_drvdata(pdev, dcdc);
926 
927 	return 0;
928 
929 err:
930 	return ret;
931 }
932 
933 static int wm831x_epe_remove(struct platform_device *pdev)
934 {
935 	struct wm831x_dcdc *dcdc = platform_get_drvdata(pdev);
936 
937 	regulator_unregister(dcdc->regulator);
938 
939 	return 0;
940 }
941 
942 static struct platform_driver wm831x_epe_driver = {
943 	.probe = wm831x_epe_probe,
944 	.remove = wm831x_epe_remove,
945 	.driver		= {
946 		.name	= "wm831x-epe",
947 		.owner	= THIS_MODULE,
948 	},
949 };
950 
951 static int __init wm831x_dcdc_init(void)
952 {
953 	int ret;
954 	ret = platform_driver_register(&wm831x_buckv_driver);
955 	if (ret != 0)
956 		pr_err("Failed to register WM831x BUCKV driver: %d\n", ret);
957 
958 	ret = platform_driver_register(&wm831x_buckp_driver);
959 	if (ret != 0)
960 		pr_err("Failed to register WM831x BUCKP driver: %d\n", ret);
961 
962 	ret = platform_driver_register(&wm831x_boostp_driver);
963 	if (ret != 0)
964 		pr_err("Failed to register WM831x BOOST driver: %d\n", ret);
965 
966 	ret = platform_driver_register(&wm831x_epe_driver);
967 	if (ret != 0)
968 		pr_err("Failed to register WM831x EPE driver: %d\n", ret);
969 
970 	return 0;
971 }
972 subsys_initcall(wm831x_dcdc_init);
973 
974 static void __exit wm831x_dcdc_exit(void)
975 {
976 	platform_driver_unregister(&wm831x_epe_driver);
977 	platform_driver_unregister(&wm831x_boostp_driver);
978 	platform_driver_unregister(&wm831x_buckp_driver);
979 	platform_driver_unregister(&wm831x_buckv_driver);
980 }
981 module_exit(wm831x_dcdc_exit);
982 
983 /* Module information */
984 MODULE_AUTHOR("Mark Brown");
985 MODULE_DESCRIPTION("WM831x DC-DC convertor driver");
986 MODULE_LICENSE("GPL");
987 MODULE_ALIAS("platform:wm831x-buckv");
988 MODULE_ALIAS("platform:wm831x-buckp");
989 MODULE_ALIAS("platform:wm831x-boostp");
990 MODULE_ALIAS("platform:wm831x-epe");
991