xref: /linux/drivers/thermal/armada_thermal.c (revision e9f0878c4b2004ac19581274c1ae4c61ae3ca70e)
1 /*
2  * Marvell EBU Armada SoCs thermal sensor driver
3  *
4  * Copyright (C) 2013 Marvell
5  *
6  * This software is licensed under the terms of the GNU General Public
7  * License version 2, as published by the Free Software Foundation, and
8  * may be copied, distributed, and modified under those terms.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  * GNU General Public License for more details.
14  *
15  */
16 #include <linux/device.h>
17 #include <linux/err.h>
18 #include <linux/io.h>
19 #include <linux/kernel.h>
20 #include <linux/of.h>
21 #include <linux/module.h>
22 #include <linux/delay.h>
23 #include <linux/platform_device.h>
24 #include <linux/of_device.h>
25 #include <linux/thermal.h>
26 #include <linux/iopoll.h>
27 #include <linux/mfd/syscon.h>
28 #include <linux/regmap.h>
29 
30 /* Thermal Manager Control and Status Register */
31 #define PMU_TDC0_SW_RST_MASK		(0x1 << 1)
32 #define PMU_TM_DISABLE_OFFS		0
33 #define PMU_TM_DISABLE_MASK		(0x1 << PMU_TM_DISABLE_OFFS)
34 #define PMU_TDC0_REF_CAL_CNT_OFFS	11
35 #define PMU_TDC0_REF_CAL_CNT_MASK	(0x1ff << PMU_TDC0_REF_CAL_CNT_OFFS)
36 #define PMU_TDC0_OTF_CAL_MASK		(0x1 << 30)
37 #define PMU_TDC0_START_CAL_MASK		(0x1 << 25)
38 
39 #define A375_UNIT_CONTROL_SHIFT		27
40 #define A375_UNIT_CONTROL_MASK		0x7
41 #define A375_READOUT_INVERT		BIT(15)
42 #define A375_HW_RESETn			BIT(8)
43 
44 /* Errata fields */
45 #define CONTROL0_TSEN_TC_TRIM_MASK	0x7
46 #define CONTROL0_TSEN_TC_TRIM_VAL	0x3
47 
48 #define CONTROL0_TSEN_START		BIT(0)
49 #define CONTROL0_TSEN_RESET		BIT(1)
50 #define CONTROL0_TSEN_ENABLE		BIT(2)
51 #define CONTROL0_TSEN_AVG_BYPASS	BIT(6)
52 #define CONTROL0_TSEN_CHAN_SHIFT	13
53 #define CONTROL0_TSEN_CHAN_MASK		0xF
54 #define CONTROL0_TSEN_OSR_SHIFT		24
55 #define CONTROL0_TSEN_OSR_MAX		0x3
56 #define CONTROL0_TSEN_MODE_SHIFT	30
57 #define CONTROL0_TSEN_MODE_EXTERNAL	0x2
58 #define CONTROL0_TSEN_MODE_MASK		0x3
59 
60 #define CONTROL1_TSEN_AVG_SHIFT		0
61 #define CONTROL1_TSEN_AVG_MASK		0x7
62 #define CONTROL1_EXT_TSEN_SW_RESET	BIT(7)
63 #define CONTROL1_EXT_TSEN_HW_RESETn	BIT(8)
64 
65 #define STATUS_POLL_PERIOD_US		1000
66 #define STATUS_POLL_TIMEOUT_US		100000
67 
68 struct armada_thermal_data;
69 
70 /* Marvell EBU Thermal Sensor Dev Structure */
71 struct armada_thermal_priv {
72 	struct device *dev;
73 	struct regmap *syscon;
74 	char zone_name[THERMAL_NAME_LENGTH];
75 	/* serialize temperature reads/updates */
76 	struct mutex update_lock;
77 	struct armada_thermal_data *data;
78 	int current_channel;
79 };
80 
81 struct armada_thermal_data {
82 	/* Initialize the thermal IC */
83 	void (*init)(struct platform_device *pdev,
84 		     struct armada_thermal_priv *priv);
85 
86 	/* Formula coeficients: temp = (b - m * reg) / div */
87 	s64 coef_b;
88 	s64 coef_m;
89 	u32 coef_div;
90 	bool inverted;
91 	bool signed_sample;
92 
93 	/* Register shift and mask to access the sensor temperature */
94 	unsigned int temp_shift;
95 	unsigned int temp_mask;
96 	u32 is_valid_bit;
97 
98 	/* Syscon access */
99 	unsigned int syscon_control0_off;
100 	unsigned int syscon_control1_off;
101 	unsigned int syscon_status_off;
102 
103 	/* One sensor is in the thermal IC, the others are in the CPUs if any */
104 	unsigned int cpu_nr;
105 };
106 
107 struct armada_drvdata {
108 	enum drvtype {
109 		LEGACY,
110 		SYSCON
111 	} type;
112 	union {
113 		struct armada_thermal_priv *priv;
114 		struct thermal_zone_device *tz;
115 	} data;
116 };
117 
118 /*
119  * struct armada_thermal_sensor - hold the information of one thermal sensor
120  * @thermal: pointer to the local private structure
121  * @tzd: pointer to the thermal zone device
122  * @id: identifier of the thermal sensor
123  */
124 struct armada_thermal_sensor {
125 	struct armada_thermal_priv *priv;
126 	int id;
127 };
128 
129 static void armadaxp_init(struct platform_device *pdev,
130 			  struct armada_thermal_priv *priv)
131 {
132 	struct armada_thermal_data *data = priv->data;
133 	u32 reg;
134 
135 	regmap_read(priv->syscon, data->syscon_control1_off, &reg);
136 	reg |= PMU_TDC0_OTF_CAL_MASK;
137 
138 	/* Reference calibration value */
139 	reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
140 	reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS);
141 
142 	/* Reset the sensor */
143 	reg |= PMU_TDC0_SW_RST_MASK;
144 
145 	regmap_write(priv->syscon, data->syscon_control1_off, reg);
146 
147 	/* Enable the sensor */
148 	regmap_read(priv->syscon, data->syscon_status_off, &reg);
149 	reg &= ~PMU_TM_DISABLE_MASK;
150 	regmap_write(priv->syscon, data->syscon_status_off, reg);
151 }
152 
153 static void armada370_init(struct platform_device *pdev,
154 			   struct armada_thermal_priv *priv)
155 {
156 	struct armada_thermal_data *data = priv->data;
157 	u32 reg;
158 
159 	regmap_read(priv->syscon, data->syscon_control1_off, &reg);
160 	reg |= PMU_TDC0_OTF_CAL_MASK;
161 
162 	/* Reference calibration value */
163 	reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
164 	reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS);
165 
166 	/* Reset the sensor */
167 	reg &= ~PMU_TDC0_START_CAL_MASK;
168 
169 	regmap_write(priv->syscon, data->syscon_control1_off, reg);
170 
171 	msleep(10);
172 }
173 
174 static void armada375_init(struct platform_device *pdev,
175 			   struct armada_thermal_priv *priv)
176 {
177 	struct armada_thermal_data *data = priv->data;
178 	u32 reg;
179 
180 	regmap_read(priv->syscon, data->syscon_control1_off, &reg);
181 	reg &= ~(A375_UNIT_CONTROL_MASK << A375_UNIT_CONTROL_SHIFT);
182 	reg &= ~A375_READOUT_INVERT;
183 	reg &= ~A375_HW_RESETn;
184 	regmap_write(priv->syscon, data->syscon_control1_off, reg);
185 
186 	msleep(20);
187 
188 	reg |= A375_HW_RESETn;
189 	regmap_write(priv->syscon, data->syscon_control1_off, reg);
190 
191 	msleep(50);
192 }
193 
194 static int armada_wait_sensor_validity(struct armada_thermal_priv *priv)
195 {
196 	u32 reg;
197 
198 	return regmap_read_poll_timeout(priv->syscon,
199 					priv->data->syscon_status_off, reg,
200 					reg & priv->data->is_valid_bit,
201 					STATUS_POLL_PERIOD_US,
202 					STATUS_POLL_TIMEOUT_US);
203 }
204 
205 static void armada380_init(struct platform_device *pdev,
206 			   struct armada_thermal_priv *priv)
207 {
208 	struct armada_thermal_data *data = priv->data;
209 	u32 reg;
210 
211 	/* Disable the HW/SW reset */
212 	regmap_read(priv->syscon, data->syscon_control1_off, &reg);
213 	reg |= CONTROL1_EXT_TSEN_HW_RESETn;
214 	reg &= ~CONTROL1_EXT_TSEN_SW_RESET;
215 	regmap_write(priv->syscon, data->syscon_control1_off, reg);
216 
217 	/* Set Tsen Tc Trim to correct default value (errata #132698) */
218 	regmap_read(priv->syscon, data->syscon_control0_off, &reg);
219 	reg &= ~CONTROL0_TSEN_TC_TRIM_MASK;
220 	reg |= CONTROL0_TSEN_TC_TRIM_VAL;
221 	regmap_write(priv->syscon, data->syscon_control0_off, reg);
222 }
223 
224 static void armada_ap806_init(struct platform_device *pdev,
225 			      struct armada_thermal_priv *priv)
226 {
227 	struct armada_thermal_data *data = priv->data;
228 	u32 reg;
229 
230 	regmap_read(priv->syscon, data->syscon_control0_off, &reg);
231 	reg &= ~CONTROL0_TSEN_RESET;
232 	reg |= CONTROL0_TSEN_START | CONTROL0_TSEN_ENABLE;
233 
234 	/* Sample every ~2ms */
235 	reg |= CONTROL0_TSEN_OSR_MAX << CONTROL0_TSEN_OSR_SHIFT;
236 
237 	/* Enable average (2 samples by default) */
238 	reg &= ~CONTROL0_TSEN_AVG_BYPASS;
239 
240 	regmap_write(priv->syscon, data->syscon_control0_off, reg);
241 }
242 
243 static void armada_cp110_init(struct platform_device *pdev,
244 			      struct armada_thermal_priv *priv)
245 {
246 	struct armada_thermal_data *data = priv->data;
247 	u32 reg;
248 
249 	armada380_init(pdev, priv);
250 
251 	/* Sample every ~2ms */
252 	regmap_read(priv->syscon, data->syscon_control0_off, &reg);
253 	reg |= CONTROL0_TSEN_OSR_MAX << CONTROL0_TSEN_OSR_SHIFT;
254 	regmap_write(priv->syscon, data->syscon_control0_off, reg);
255 
256 	/* Average the output value over 2^1 = 2 samples */
257 	regmap_read(priv->syscon, data->syscon_control1_off, &reg);
258 	reg &= ~CONTROL1_TSEN_AVG_MASK << CONTROL1_TSEN_AVG_SHIFT;
259 	reg |= 1 << CONTROL1_TSEN_AVG_SHIFT;
260 	regmap_write(priv->syscon, data->syscon_control1_off, reg);
261 }
262 
263 static bool armada_is_valid(struct armada_thermal_priv *priv)
264 {
265 	u32 reg;
266 
267 	if (!priv->data->is_valid_bit)
268 		return true;
269 
270 	regmap_read(priv->syscon, priv->data->syscon_status_off, &reg);
271 
272 	return reg & priv->data->is_valid_bit;
273 }
274 
275 /* There is currently no board with more than one sensor per channel */
276 static int armada_select_channel(struct armada_thermal_priv *priv, int channel)
277 {
278 	struct armada_thermal_data *data = priv->data;
279 	u32 ctrl0;
280 
281 	if (channel < 0 || channel > priv->data->cpu_nr)
282 		return -EINVAL;
283 
284 	if (priv->current_channel == channel)
285 		return 0;
286 
287 	/* Stop the measurements */
288 	regmap_read(priv->syscon, data->syscon_control0_off, &ctrl0);
289 	ctrl0 &= ~CONTROL0_TSEN_START;
290 	regmap_write(priv->syscon, data->syscon_control0_off, ctrl0);
291 
292 	/* Reset the mode, internal sensor will be automatically selected */
293 	ctrl0 &= ~(CONTROL0_TSEN_MODE_MASK << CONTROL0_TSEN_MODE_SHIFT);
294 
295 	/* Other channels are external and should be selected accordingly */
296 	if (channel) {
297 		/* Change the mode to external */
298 		ctrl0 |= CONTROL0_TSEN_MODE_EXTERNAL <<
299 			 CONTROL0_TSEN_MODE_SHIFT;
300 		/* Select the sensor */
301 		ctrl0 &= ~(CONTROL0_TSEN_CHAN_MASK << CONTROL0_TSEN_CHAN_SHIFT);
302 		ctrl0 |= (channel - 1) << CONTROL0_TSEN_CHAN_SHIFT;
303 	}
304 
305 	/* Actually set the mode/channel */
306 	regmap_write(priv->syscon, data->syscon_control0_off, ctrl0);
307 	priv->current_channel = channel;
308 
309 	/* Re-start the measurements */
310 	ctrl0 |= CONTROL0_TSEN_START;
311 	regmap_write(priv->syscon, data->syscon_control0_off, ctrl0);
312 
313 	/*
314 	 * The IP has a latency of ~15ms, so after updating the selected source,
315 	 * we must absolutely wait for the sensor validity bit to ensure we read
316 	 * actual data.
317 	 */
318 	if (armada_wait_sensor_validity(priv)) {
319 		dev_err(priv->dev,
320 			"Temperature sensor reading not valid\n");
321 		return -EIO;
322 	}
323 
324 	return 0;
325 }
326 
327 static int armada_read_sensor(struct armada_thermal_priv *priv, int *temp)
328 {
329 	u32 reg, div;
330 	s64 sample, b, m;
331 
332 	regmap_read(priv->syscon, priv->data->syscon_status_off, &reg);
333 	reg = (reg >> priv->data->temp_shift) & priv->data->temp_mask;
334 	if (priv->data->signed_sample)
335 		/* The most significant bit is the sign bit */
336 		sample = sign_extend32(reg, fls(priv->data->temp_mask) - 1);
337 	else
338 		sample = reg;
339 
340 	/* Get formula coeficients */
341 	b = priv->data->coef_b;
342 	m = priv->data->coef_m;
343 	div = priv->data->coef_div;
344 
345 	if (priv->data->inverted)
346 		*temp = div_s64((m * sample) - b, div);
347 	else
348 		*temp = div_s64(b - (m * sample), div);
349 
350 	return 0;
351 }
352 
353 static int armada_get_temp_legacy(struct thermal_zone_device *thermal,
354 				  int *temp)
355 {
356 	struct armada_thermal_priv *priv = thermal->devdata;
357 	int ret;
358 
359 	/* Valid check */
360 	if (armada_is_valid(priv)) {
361 		dev_err(priv->dev,
362 			"Temperature sensor reading not valid\n");
363 		return -EIO;
364 	}
365 
366 	/* Do the actual reading */
367 	ret = armada_read_sensor(priv, temp);
368 
369 	return ret;
370 }
371 
372 static struct thermal_zone_device_ops legacy_ops = {
373 	.get_temp = armada_get_temp_legacy,
374 };
375 
376 static int armada_get_temp(void *_sensor, int *temp)
377 {
378 	struct armada_thermal_sensor *sensor = _sensor;
379 	struct armada_thermal_priv *priv = sensor->priv;
380 	int ret;
381 
382 	mutex_lock(&priv->update_lock);
383 
384 	/* Select the desired channel */
385 	ret = armada_select_channel(priv, sensor->id);
386 	if (ret)
387 		goto unlock_mutex;
388 
389 	/* Do the actual reading */
390 	ret = armada_read_sensor(priv, temp);
391 
392 unlock_mutex:
393 	mutex_unlock(&priv->update_lock);
394 
395 	return ret;
396 }
397 
398 static struct thermal_zone_of_device_ops of_ops = {
399 	.get_temp = armada_get_temp,
400 };
401 
402 static const struct armada_thermal_data armadaxp_data = {
403 	.init = armadaxp_init,
404 	.temp_shift = 10,
405 	.temp_mask = 0x1ff,
406 	.coef_b = 3153000000ULL,
407 	.coef_m = 10000000ULL,
408 	.coef_div = 13825,
409 	.syscon_status_off = 0xb0,
410 	.syscon_control1_off = 0xd0,
411 };
412 
413 static const struct armada_thermal_data armada370_data = {
414 	.init = armada370_init,
415 	.is_valid_bit = BIT(9),
416 	.temp_shift = 10,
417 	.temp_mask = 0x1ff,
418 	.coef_b = 3153000000ULL,
419 	.coef_m = 10000000ULL,
420 	.coef_div = 13825,
421 	.syscon_status_off = 0x0,
422 	.syscon_control1_off = 0x4,
423 };
424 
425 static const struct armada_thermal_data armada375_data = {
426 	.init = armada375_init,
427 	.is_valid_bit = BIT(10),
428 	.temp_shift = 0,
429 	.temp_mask = 0x1ff,
430 	.coef_b = 3171900000ULL,
431 	.coef_m = 10000000ULL,
432 	.coef_div = 13616,
433 	.syscon_status_off = 0x78,
434 	.syscon_control0_off = 0x7c,
435 	.syscon_control1_off = 0x80,
436 };
437 
438 static const struct armada_thermal_data armada380_data = {
439 	.init = armada380_init,
440 	.is_valid_bit = BIT(10),
441 	.temp_shift = 0,
442 	.temp_mask = 0x3ff,
443 	.coef_b = 1172499100ULL,
444 	.coef_m = 2000096ULL,
445 	.coef_div = 4201,
446 	.inverted = true,
447 	.syscon_control0_off = 0x70,
448 	.syscon_control1_off = 0x74,
449 	.syscon_status_off = 0x78,
450 };
451 
452 static const struct armada_thermal_data armada_ap806_data = {
453 	.init = armada_ap806_init,
454 	.is_valid_bit = BIT(16),
455 	.temp_shift = 0,
456 	.temp_mask = 0x3ff,
457 	.coef_b = -150000LL,
458 	.coef_m = 423ULL,
459 	.coef_div = 1,
460 	.inverted = true,
461 	.signed_sample = true,
462 	.syscon_control0_off = 0x84,
463 	.syscon_control1_off = 0x88,
464 	.syscon_status_off = 0x8C,
465 	.cpu_nr = 4,
466 };
467 
468 static const struct armada_thermal_data armada_cp110_data = {
469 	.init = armada_cp110_init,
470 	.is_valid_bit = BIT(10),
471 	.temp_shift = 0,
472 	.temp_mask = 0x3ff,
473 	.coef_b = 1172499100ULL,
474 	.coef_m = 2000096ULL,
475 	.coef_div = 4201,
476 	.inverted = true,
477 	.syscon_control0_off = 0x70,
478 	.syscon_control1_off = 0x74,
479 	.syscon_status_off = 0x78,
480 };
481 
482 static const struct of_device_id armada_thermal_id_table[] = {
483 	{
484 		.compatible = "marvell,armadaxp-thermal",
485 		.data       = &armadaxp_data,
486 	},
487 	{
488 		.compatible = "marvell,armada370-thermal",
489 		.data       = &armada370_data,
490 	},
491 	{
492 		.compatible = "marvell,armada375-thermal",
493 		.data       = &armada375_data,
494 	},
495 	{
496 		.compatible = "marvell,armada380-thermal",
497 		.data       = &armada380_data,
498 	},
499 	{
500 		.compatible = "marvell,armada-ap806-thermal",
501 		.data       = &armada_ap806_data,
502 	},
503 	{
504 		.compatible = "marvell,armada-cp110-thermal",
505 		.data       = &armada_cp110_data,
506 	},
507 	{
508 		/* sentinel */
509 	},
510 };
511 MODULE_DEVICE_TABLE(of, armada_thermal_id_table);
512 
513 static const struct regmap_config armada_thermal_regmap_config = {
514 	.reg_bits = 32,
515 	.reg_stride = 4,
516 	.val_bits = 32,
517 	.fast_io = true,
518 };
519 
520 static int armada_thermal_probe_legacy(struct platform_device *pdev,
521 				       struct armada_thermal_priv *priv)
522 {
523 	struct armada_thermal_data *data = priv->data;
524 	struct resource *res;
525 	void __iomem *base;
526 
527 	/* First memory region points towards the status register */
528 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
529 	if (IS_ERR(res))
530 		return PTR_ERR(res);
531 
532 	/*
533 	 * Edit the resource start address and length to map over all the
534 	 * registers, instead of pointing at them one by one.
535 	 */
536 	res->start -= data->syscon_status_off;
537 	res->end = res->start + max(data->syscon_status_off,
538 				    max(data->syscon_control0_off,
539 					data->syscon_control1_off)) +
540 		   sizeof(unsigned int) - 1;
541 
542 	base = devm_ioremap_resource(&pdev->dev, res);
543 	if (IS_ERR(base))
544 		return PTR_ERR(base);
545 
546 	priv->syscon = devm_regmap_init_mmio(&pdev->dev, base,
547 					     &armada_thermal_regmap_config);
548 	if (IS_ERR(priv->syscon))
549 		return PTR_ERR(priv->syscon);
550 
551 	return 0;
552 }
553 
554 static int armada_thermal_probe_syscon(struct platform_device *pdev,
555 				       struct armada_thermal_priv *priv)
556 {
557 	priv->syscon = syscon_node_to_regmap(pdev->dev.parent->of_node);
558 	if (IS_ERR(priv->syscon))
559 		return PTR_ERR(priv->syscon);
560 
561 	return 0;
562 }
563 
564 static void armada_set_sane_name(struct platform_device *pdev,
565 				 struct armada_thermal_priv *priv)
566 {
567 	const char *name = dev_name(&pdev->dev);
568 	char *insane_char;
569 
570 	if (strlen(name) > THERMAL_NAME_LENGTH) {
571 		/*
572 		 * When inside a system controller, the device name has the
573 		 * form: f06f8000.system-controller:ap-thermal so stripping
574 		 * after the ':' should give us a shorter but meaningful name.
575 		 */
576 		name = strrchr(name, ':');
577 		if (!name)
578 			name = "armada_thermal";
579 		else
580 			name++;
581 	}
582 
583 	/* Save the name locally */
584 	strncpy(priv->zone_name, name, THERMAL_NAME_LENGTH - 1);
585 	priv->zone_name[THERMAL_NAME_LENGTH - 1] = '\0';
586 
587 	/* Then check there are no '-' or hwmon core will complain */
588 	do {
589 		insane_char = strpbrk(priv->zone_name, "-");
590 		if (insane_char)
591 			*insane_char = '_';
592 	} while (insane_char);
593 }
594 
595 static int armada_thermal_probe(struct platform_device *pdev)
596 {
597 	struct thermal_zone_device *tz;
598 	struct armada_thermal_sensor *sensor;
599 	struct armada_drvdata *drvdata;
600 	const struct of_device_id *match;
601 	struct armada_thermal_priv *priv;
602 	int sensor_id;
603 	int ret;
604 
605 	match = of_match_device(armada_thermal_id_table, &pdev->dev);
606 	if (!match)
607 		return -ENODEV;
608 
609 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
610 	if (!priv)
611 		return -ENOMEM;
612 
613 	drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
614 	if (!drvdata)
615 		return -ENOMEM;
616 
617 	priv->dev = &pdev->dev;
618 	priv->data = (struct armada_thermal_data *)match->data;
619 
620 	mutex_init(&priv->update_lock);
621 
622 	/*
623 	 * Legacy DT bindings only described "control1" register (also referred
624 	 * as "control MSB" on old documentation). Then, bindings moved to cover
625 	 * "control0/control LSB" and "control1/control MSB" registers within
626 	 * the same resource, which was then of size 8 instead of 4.
627 	 *
628 	 * The logic of defining sporadic registers is broken. For instance, it
629 	 * blocked the addition of the overheat interrupt feature that needed
630 	 * another resource somewhere else in the same memory area. One solution
631 	 * is to define an overall system controller and put the thermal node
632 	 * into it, which requires the use of regmaps across all the driver.
633 	 */
634 	if (IS_ERR(syscon_node_to_regmap(pdev->dev.parent->of_node))) {
635 		/* Ensure device name is correct for the thermal core */
636 		armada_set_sane_name(pdev, priv);
637 
638 		ret = armada_thermal_probe_legacy(pdev, priv);
639 		if (ret)
640 			return ret;
641 
642 		priv->data->init(pdev, priv);
643 
644 		/* Wait the sensors to be valid */
645 		armada_wait_sensor_validity(priv);
646 
647 		tz = thermal_zone_device_register(priv->zone_name, 0, 0, priv,
648 						  &legacy_ops, NULL, 0, 0);
649 		if (IS_ERR(tz)) {
650 			dev_err(&pdev->dev,
651 				"Failed to register thermal zone device\n");
652 			return PTR_ERR(tz);
653 		}
654 
655 		drvdata->type = LEGACY;
656 		drvdata->data.tz = tz;
657 		platform_set_drvdata(pdev, drvdata);
658 
659 		return 0;
660 	}
661 
662 	ret = armada_thermal_probe_syscon(pdev, priv);
663 	if (ret)
664 		return ret;
665 
666 	priv->current_channel = -1;
667 	priv->data->init(pdev, priv);
668 	drvdata->type = SYSCON;
669 	drvdata->data.priv = priv;
670 	platform_set_drvdata(pdev, drvdata);
671 
672 	/*
673 	 * There is one channel for the IC and one per CPU (if any), each
674 	 * channel has one sensor.
675 	 */
676 	for (sensor_id = 0; sensor_id <= priv->data->cpu_nr; sensor_id++) {
677 		sensor = devm_kzalloc(&pdev->dev,
678 				      sizeof(struct armada_thermal_sensor),
679 				      GFP_KERNEL);
680 		if (!sensor)
681 			return -ENOMEM;
682 
683 		/* Register the sensor */
684 		sensor->priv = priv;
685 		sensor->id = sensor_id;
686 		tz = devm_thermal_zone_of_sensor_register(&pdev->dev,
687 							  sensor->id, sensor,
688 							  &of_ops);
689 		if (IS_ERR(tz)) {
690 			dev_info(&pdev->dev, "Thermal sensor %d unavailable\n",
691 				 sensor_id);
692 			devm_kfree(&pdev->dev, sensor);
693 			continue;
694 		}
695 	}
696 
697 	return 0;
698 }
699 
700 static int armada_thermal_exit(struct platform_device *pdev)
701 {
702 	struct armada_drvdata *drvdata = platform_get_drvdata(pdev);
703 
704 	if (drvdata->type == LEGACY)
705 		thermal_zone_device_unregister(drvdata->data.tz);
706 
707 	return 0;
708 }
709 
710 static struct platform_driver armada_thermal_driver = {
711 	.probe = armada_thermal_probe,
712 	.remove = armada_thermal_exit,
713 	.driver = {
714 		.name = "armada_thermal",
715 		.of_match_table = armada_thermal_id_table,
716 	},
717 };
718 
719 module_platform_driver(armada_thermal_driver);
720 
721 MODULE_AUTHOR("Ezequiel Garcia <ezequiel.garcia@free-electrons.com>");
722 MODULE_DESCRIPTION("Marvell EBU Armada SoCs thermal driver");
723 MODULE_LICENSE("GPL v2");
724