xref: /linux/drivers/thermal/ti-soc-thermal/ti-bandgap.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * TI Bandgap temperature sensor driver
3  *
4  * Copyright (C) 2011-2012 Texas Instruments Incorporated - http://www.ti.com/
5  * Author: J Keerthy <j-keerthy@ti.com>
6  * Author: Moiz Sonasath <m-sonasath@ti.com>
7  * Couple of fixes, DT and MFD adaptation:
8  *   Eduardo Valentin <eduardo.valentin@ti.com>
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License
12  * version 2 as published by the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
22  * 02110-1301 USA
23  *
24  */
25 
26 #include <linux/module.h>
27 #include <linux/export.h>
28 #include <linux/init.h>
29 #include <linux/kernel.h>
30 #include <linux/interrupt.h>
31 #include <linux/clk.h>
32 #include <linux/gpio.h>
33 #include <linux/platform_device.h>
34 #include <linux/err.h>
35 #include <linux/types.h>
36 #include <linux/spinlock.h>
37 #include <linux/reboot.h>
38 #include <linux/of_device.h>
39 #include <linux/of_platform.h>
40 #include <linux/of_irq.h>
41 #include <linux/of_gpio.h>
42 #include <linux/io.h>
43 
44 #include "ti-bandgap.h"
45 
46 static int ti_bandgap_force_single_read(struct ti_bandgap *bgp, int id);
47 
48 /***   Helper functions to access registers and their bitfields   ***/
49 
50 /**
51  * ti_bandgap_readl() - simple read helper function
52  * @bgp: pointer to ti_bandgap structure
53  * @reg: desired register (offset) to be read
54  *
55  * Helper function to read bandgap registers. It uses the io remapped area.
56  * Return: the register value.
57  */
58 static u32 ti_bandgap_readl(struct ti_bandgap *bgp, u32 reg)
59 {
60 	return readl(bgp->base + reg);
61 }
62 
63 /**
64  * ti_bandgap_writel() - simple write helper function
65  * @bgp: pointer to ti_bandgap structure
66  * @val: desired register value to be written
67  * @reg: desired register (offset) to be written
68  *
69  * Helper function to write bandgap registers. It uses the io remapped area.
70  */
71 static void ti_bandgap_writel(struct ti_bandgap *bgp, u32 val, u32 reg)
72 {
73 	writel(val, bgp->base + reg);
74 }
75 
76 /**
77  * DOC: macro to update bits.
78  *
79  * RMW_BITS() - used to read, modify and update bandgap bitfields.
80  *            The value passed will be shifted.
81  */
82 #define RMW_BITS(bgp, id, reg, mask, val)			\
83 do {								\
84 	struct temp_sensor_registers *t;			\
85 	u32 r;							\
86 								\
87 	t = bgp->conf->sensors[(id)].registers;		\
88 	r = ti_bandgap_readl(bgp, t->reg);			\
89 	r &= ~t->mask;						\
90 	r |= (val) << __ffs(t->mask);				\
91 	ti_bandgap_writel(bgp, r, t->reg);			\
92 } while (0)
93 
94 /***   Basic helper functions   ***/
95 
96 /**
97  * ti_bandgap_power() - controls the power state of a bandgap device
98  * @bgp: pointer to ti_bandgap structure
99  * @on: desired power state (1 - on, 0 - off)
100  *
101  * Used to power on/off a bandgap device instance. Only used on those
102  * that features tempsoff bit.
103  *
104  * Return: 0 on success, -ENOTSUPP if tempsoff is not supported.
105  */
106 static int ti_bandgap_power(struct ti_bandgap *bgp, bool on)
107 {
108 	int i;
109 
110 	if (!TI_BANDGAP_HAS(bgp, POWER_SWITCH))
111 		return -ENOTSUPP;
112 
113 	for (i = 0; i < bgp->conf->sensor_count; i++)
114 		/* active on 0 */
115 		RMW_BITS(bgp, i, temp_sensor_ctrl, bgap_tempsoff_mask, !on);
116 	return 0;
117 }
118 
119 /**
120  * ti_errata814_bandgap_read_temp() - helper function to read dra7 sensor temperature
121  * @bgp: pointer to ti_bandgap structure
122  * @reg: desired register (offset) to be read
123  *
124  * Function to read dra7 bandgap sensor temperature. This is done separately
125  * so as to workaround the errata "Bandgap Temperature read Dtemp can be
126  * corrupted" - Errata ID: i814".
127  * Read accesses to registers listed below can be corrupted due to incorrect
128  * resynchronization between clock domains.
129  * Read access to registers below can be corrupted :
130  * CTRL_CORE_DTEMP_MPU/GPU/CORE/DSPEVE/IVA_n (n = 0 to 4)
131  * CTRL_CORE_TEMP_SENSOR_MPU/GPU/CORE/DSPEVE/IVA_n
132  *
133  * Return: the register value.
134  */
135 static u32 ti_errata814_bandgap_read_temp(struct ti_bandgap *bgp,  u32 reg)
136 {
137 	u32 val1, val2;
138 
139 	val1 = ti_bandgap_readl(bgp, reg);
140 	val2 = ti_bandgap_readl(bgp, reg);
141 
142 	/* If both times we read the same value then that is right */
143 	if (val1 == val2)
144 		return val1;
145 
146 	/* if val1 and val2 are different read it third time */
147 	return ti_bandgap_readl(bgp, reg);
148 }
149 
150 /**
151  * ti_bandgap_read_temp() - helper function to read sensor temperature
152  * @bgp: pointer to ti_bandgap structure
153  * @id: bandgap sensor id
154  *
155  * Function to concentrate the steps to read sensor temperature register.
156  * This function is desired because, depending on bandgap device version,
157  * it might be needed to freeze the bandgap state machine, before fetching
158  * the register value.
159  *
160  * Return: temperature in ADC values.
161  */
162 static u32 ti_bandgap_read_temp(struct ti_bandgap *bgp, int id)
163 {
164 	struct temp_sensor_registers *tsr;
165 	u32 temp, reg;
166 
167 	tsr = bgp->conf->sensors[id].registers;
168 	reg = tsr->temp_sensor_ctrl;
169 
170 	if (TI_BANDGAP_HAS(bgp, FREEZE_BIT)) {
171 		RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 1);
172 		/*
173 		 * In case we cannot read from cur_dtemp / dtemp_0,
174 		 * then we read from the last valid temp read
175 		 */
176 		reg = tsr->ctrl_dtemp_1;
177 	}
178 
179 	/* read temperature */
180 	if (TI_BANDGAP_HAS(bgp, ERRATA_814))
181 		temp = ti_errata814_bandgap_read_temp(bgp, reg);
182 	else
183 		temp = ti_bandgap_readl(bgp, reg);
184 
185 	temp &= tsr->bgap_dtemp_mask;
186 
187 	if (TI_BANDGAP_HAS(bgp, FREEZE_BIT))
188 		RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 0);
189 
190 	return temp;
191 }
192 
193 /***   IRQ handlers   ***/
194 
195 /**
196  * ti_bandgap_talert_irq_handler() - handles Temperature alert IRQs
197  * @irq: IRQ number
198  * @data: private data (struct ti_bandgap *)
199  *
200  * This is the Talert handler. Use it only if bandgap device features
201  * HAS(TALERT). This handler goes over all sensors and checks their
202  * conditions and acts accordingly. In case there are events pending,
203  * it will reset the event mask to wait for the opposite event (next event).
204  * Every time there is a new event, it will be reported to thermal layer.
205  *
206  * Return: IRQ_HANDLED
207  */
208 static irqreturn_t ti_bandgap_talert_irq_handler(int irq, void *data)
209 {
210 	struct ti_bandgap *bgp = data;
211 	struct temp_sensor_registers *tsr;
212 	u32 t_hot = 0, t_cold = 0, ctrl;
213 	int i;
214 
215 	spin_lock(&bgp->lock);
216 	for (i = 0; i < bgp->conf->sensor_count; i++) {
217 		tsr = bgp->conf->sensors[i].registers;
218 		ctrl = ti_bandgap_readl(bgp, tsr->bgap_status);
219 
220 		/* Read the status of t_hot */
221 		t_hot = ctrl & tsr->status_hot_mask;
222 
223 		/* Read the status of t_cold */
224 		t_cold = ctrl & tsr->status_cold_mask;
225 
226 		if (!t_cold && !t_hot)
227 			continue;
228 
229 		ctrl = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
230 		/*
231 		 * One TALERT interrupt: Two sources
232 		 * If the interrupt is due to t_hot then mask t_hot and
233 		 * and unmask t_cold else mask t_cold and unmask t_hot
234 		 */
235 		if (t_hot) {
236 			ctrl &= ~tsr->mask_hot_mask;
237 			ctrl |= tsr->mask_cold_mask;
238 		} else if (t_cold) {
239 			ctrl &= ~tsr->mask_cold_mask;
240 			ctrl |= tsr->mask_hot_mask;
241 		}
242 
243 		ti_bandgap_writel(bgp, ctrl, tsr->bgap_mask_ctrl);
244 
245 		dev_dbg(bgp->dev,
246 			"%s: IRQ from %s sensor: hotevent %d coldevent %d\n",
247 			__func__, bgp->conf->sensors[i].domain,
248 			t_hot, t_cold);
249 
250 		/* report temperature to whom may concern */
251 		if (bgp->conf->report_temperature)
252 			bgp->conf->report_temperature(bgp, i);
253 	}
254 	spin_unlock(&bgp->lock);
255 
256 	return IRQ_HANDLED;
257 }
258 
259 /**
260  * ti_bandgap_tshut_irq_handler() - handles Temperature shutdown signal
261  * @irq: IRQ number
262  * @data: private data (unused)
263  *
264  * This is the Tshut handler. Use it only if bandgap device features
265  * HAS(TSHUT). If any sensor fires the Tshut signal, we simply shutdown
266  * the system.
267  *
268  * Return: IRQ_HANDLED
269  */
270 static irqreturn_t ti_bandgap_tshut_irq_handler(int irq, void *data)
271 {
272 	pr_emerg("%s: TSHUT temperature reached. Needs shut down...\n",
273 		 __func__);
274 
275 	orderly_poweroff(true);
276 
277 	return IRQ_HANDLED;
278 }
279 
280 /***   Helper functions which manipulate conversion ADC <-> mi Celsius   ***/
281 
282 /**
283  * ti_bandgap_adc_to_mcelsius() - converts an ADC value to mCelsius scale
284  * @bgp: struct ti_bandgap pointer
285  * @adc_val: value in ADC representation
286  * @t: address where to write the resulting temperature in mCelsius
287  *
288  * Simple conversion from ADC representation to mCelsius. In case the ADC value
289  * is out of the ADC conv table range, it returns -ERANGE, 0 on success.
290  * The conversion table is indexed by the ADC values.
291  *
292  * Return: 0 if conversion was successful, else -ERANGE in case the @adc_val
293  * argument is out of the ADC conv table range.
294  */
295 static
296 int ti_bandgap_adc_to_mcelsius(struct ti_bandgap *bgp, int adc_val, int *t)
297 {
298 	const struct ti_bandgap_data *conf = bgp->conf;
299 
300 	/* look up for temperature in the table and return the temperature */
301 	if (adc_val < conf->adc_start_val || adc_val > conf->adc_end_val)
302 		return -ERANGE;
303 
304 	*t = bgp->conf->conv_table[adc_val - conf->adc_start_val];
305 	return 0;
306 }
307 
308 /**
309  * ti_bandgap_mcelsius_to_adc() - converts a mCelsius value to ADC scale
310  * @bgp: struct ti_bandgap pointer
311  * @temp: value in mCelsius
312  * @adc: address where to write the resulting temperature in ADC representation
313  *
314  * Simple conversion from mCelsius to ADC values. In case the temp value
315  * is out of the ADC conv table range, it returns -ERANGE, 0 on success.
316  * The conversion table is indexed by the ADC values.
317  *
318  * Return: 0 if conversion was successful, else -ERANGE in case the @temp
319  * argument is out of the ADC conv table range.
320  */
321 static
322 int ti_bandgap_mcelsius_to_adc(struct ti_bandgap *bgp, long temp, int *adc)
323 {
324 	const struct ti_bandgap_data *conf = bgp->conf;
325 	const int *conv_table = bgp->conf->conv_table;
326 	int high, low, mid;
327 
328 	low = 0;
329 	high = conf->adc_end_val - conf->adc_start_val;
330 	mid = (high + low) / 2;
331 
332 	if (temp < conv_table[low] || temp > conv_table[high])
333 		return -ERANGE;
334 
335 	while (low < high) {
336 		if (temp < conv_table[mid])
337 			high = mid - 1;
338 		else
339 			low = mid + 1;
340 		mid = (low + high) / 2;
341 	}
342 
343 	*adc = conf->adc_start_val + low;
344 	return 0;
345 }
346 
347 /**
348  * ti_bandgap_add_hyst() - add hysteresis (in mCelsius) to an ADC value
349  * @bgp: struct ti_bandgap pointer
350  * @adc_val: temperature value in ADC representation
351  * @hyst_val: hysteresis value in mCelsius
352  * @sum: address where to write the resulting temperature (in ADC scale)
353  *
354  * Adds an hysteresis value (in mCelsius) to a ADC temperature value.
355  *
356  * Return: 0 on success, -ERANGE otherwise.
357  */
358 static
359 int ti_bandgap_add_hyst(struct ti_bandgap *bgp, int adc_val, int hyst_val,
360 			u32 *sum)
361 {
362 	int temp, ret;
363 
364 	/*
365 	 * Need to add in the mcelsius domain, so we have a temperature
366 	 * the conv_table range
367 	 */
368 	ret = ti_bandgap_adc_to_mcelsius(bgp, adc_val, &temp);
369 	if (ret < 0)
370 		return ret;
371 
372 	temp += hyst_val;
373 
374 	ret = ti_bandgap_mcelsius_to_adc(bgp, temp, sum);
375 	return ret;
376 }
377 
378 /***   Helper functions handling device Alert/Shutdown signals   ***/
379 
380 /**
381  * ti_bandgap_unmask_interrupts() - unmasks the events of thot & tcold
382  * @bgp: struct ti_bandgap pointer
383  * @id: bandgap sensor id
384  * @t_hot: hot temperature value to trigger alert signal
385  * @t_cold: cold temperature value to trigger alert signal
386  *
387  * Checks the requested t_hot and t_cold values and configures the IRQ event
388  * masks accordingly. Call this function only if bandgap features HAS(TALERT).
389  */
390 static void ti_bandgap_unmask_interrupts(struct ti_bandgap *bgp, int id,
391 					 u32 t_hot, u32 t_cold)
392 {
393 	struct temp_sensor_registers *tsr;
394 	u32 temp, reg_val;
395 
396 	/* Read the current on die temperature */
397 	temp = ti_bandgap_read_temp(bgp, id);
398 
399 	tsr = bgp->conf->sensors[id].registers;
400 	reg_val = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
401 
402 	if (temp < t_hot)
403 		reg_val |= tsr->mask_hot_mask;
404 	else
405 		reg_val &= ~tsr->mask_hot_mask;
406 
407 	if (t_cold < temp)
408 		reg_val |= tsr->mask_cold_mask;
409 	else
410 		reg_val &= ~tsr->mask_cold_mask;
411 	ti_bandgap_writel(bgp, reg_val, tsr->bgap_mask_ctrl);
412 }
413 
414 /**
415  * ti_bandgap_update_alert_threshold() - sequence to update thresholds
416  * @bgp: struct ti_bandgap pointer
417  * @id: bandgap sensor id
418  * @val: value (ADC) of a new threshold
419  * @hot: desired threshold to be updated. true if threshold hot, false if
420  *       threshold cold
421  *
422  * It will program the required thresholds (hot and cold) for TALERT signal.
423  * This function can be used to update t_hot or t_cold, depending on @hot value.
424  * It checks the resulting t_hot and t_cold values, based on the new passed @val
425  * and configures the thresholds so that t_hot is always greater than t_cold.
426  * Call this function only if bandgap features HAS(TALERT).
427  *
428  * Return: 0 if no error, else corresponding error
429  */
430 static int ti_bandgap_update_alert_threshold(struct ti_bandgap *bgp, int id,
431 					     int val, bool hot)
432 {
433 	struct temp_sensor_data *ts_data = bgp->conf->sensors[id].ts_data;
434 	struct temp_sensor_registers *tsr;
435 	u32 thresh_val, reg_val, t_hot, t_cold, ctrl;
436 	int err = 0;
437 
438 	tsr = bgp->conf->sensors[id].registers;
439 
440 	/* obtain the current value */
441 	thresh_val = ti_bandgap_readl(bgp, tsr->bgap_threshold);
442 	t_cold = (thresh_val & tsr->threshold_tcold_mask) >>
443 		__ffs(tsr->threshold_tcold_mask);
444 	t_hot = (thresh_val & tsr->threshold_thot_mask) >>
445 		__ffs(tsr->threshold_thot_mask);
446 	if (hot)
447 		t_hot = val;
448 	else
449 		t_cold = val;
450 
451 	if (t_cold > t_hot) {
452 		if (hot)
453 			err = ti_bandgap_add_hyst(bgp, t_hot,
454 						  -ts_data->hyst_val,
455 						  &t_cold);
456 		else
457 			err = ti_bandgap_add_hyst(bgp, t_cold,
458 						  ts_data->hyst_val,
459 						  &t_hot);
460 	}
461 
462 	/* write the new threshold values */
463 	reg_val = thresh_val &
464 		  ~(tsr->threshold_thot_mask | tsr->threshold_tcold_mask);
465 	reg_val |= (t_hot << __ffs(tsr->threshold_thot_mask)) |
466 		   (t_cold << __ffs(tsr->threshold_tcold_mask));
467 
468 	/**
469 	 * Errata i813:
470 	 * Spurious Thermal Alert: Talert can happen randomly while the device
471 	 * remains under the temperature limit defined for this event to trig.
472 	 * This spurious event is caused by a incorrect re-synchronization
473 	 * between clock domains. The comparison between configured threshold
474 	 * and current temperature value can happen while the value is
475 	 * transitioning (metastable), thus causing inappropriate event
476 	 * generation. No spurious event occurs as long as the threshold value
477 	 * stays unchanged. Spurious event can be generated while a thermal
478 	 * alert threshold is modified in
479 	 * CONTROL_BANDGAP_THRESHOLD_MPU/GPU/CORE/DSPEVE/IVA_n.
480 	 */
481 
482 	if (TI_BANDGAP_HAS(bgp, ERRATA_813)) {
483 		/* Mask t_hot and t_cold events at the IP Level */
484 		ctrl = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
485 
486 		if (hot)
487 			ctrl &= ~tsr->mask_hot_mask;
488 		else
489 			ctrl &= ~tsr->mask_cold_mask;
490 
491 		ti_bandgap_writel(bgp, ctrl, tsr->bgap_mask_ctrl);
492 	}
493 
494 	/* Write the threshold value */
495 	ti_bandgap_writel(bgp, reg_val, tsr->bgap_threshold);
496 
497 	if (TI_BANDGAP_HAS(bgp, ERRATA_813)) {
498 		/* Unmask t_hot and t_cold events at the IP Level */
499 		ctrl = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
500 		if (hot)
501 			ctrl |= tsr->mask_hot_mask;
502 		else
503 			ctrl |= tsr->mask_cold_mask;
504 
505 		ti_bandgap_writel(bgp, ctrl, tsr->bgap_mask_ctrl);
506 	}
507 
508 	if (err) {
509 		dev_err(bgp->dev, "failed to reprogram thot threshold\n");
510 		err = -EIO;
511 		goto exit;
512 	}
513 
514 	ti_bandgap_unmask_interrupts(bgp, id, t_hot, t_cold);
515 exit:
516 	return err;
517 }
518 
519 /**
520  * ti_bandgap_validate() - helper to check the sanity of a struct ti_bandgap
521  * @bgp: struct ti_bandgap pointer
522  * @id: bandgap sensor id
523  *
524  * Checks if the bandgap pointer is valid and if the sensor id is also
525  * applicable.
526  *
527  * Return: 0 if no errors, -EINVAL for invalid @bgp pointer or -ERANGE if
528  * @id cannot index @bgp sensors.
529  */
530 static inline int ti_bandgap_validate(struct ti_bandgap *bgp, int id)
531 {
532 	if (!bgp || IS_ERR(bgp)) {
533 		pr_err("%s: invalid bandgap pointer\n", __func__);
534 		return -EINVAL;
535 	}
536 
537 	if ((id < 0) || (id >= bgp->conf->sensor_count)) {
538 		dev_err(bgp->dev, "%s: sensor id out of range (%d)\n",
539 			__func__, id);
540 		return -ERANGE;
541 	}
542 
543 	return 0;
544 }
545 
546 /**
547  * _ti_bandgap_write_threshold() - helper to update TALERT t_cold or t_hot
548  * @bgp: struct ti_bandgap pointer
549  * @id: bandgap sensor id
550  * @val: value (mCelsius) of a new threshold
551  * @hot: desired threshold to be updated. true if threshold hot, false if
552  *       threshold cold
553  *
554  * It will update the required thresholds (hot and cold) for TALERT signal.
555  * This function can be used to update t_hot or t_cold, depending on @hot value.
556  * Validates the mCelsius range and update the requested threshold.
557  * Call this function only if bandgap features HAS(TALERT).
558  *
559  * Return: 0 if no error, else corresponding error value.
560  */
561 static int _ti_bandgap_write_threshold(struct ti_bandgap *bgp, int id, int val,
562 				       bool hot)
563 {
564 	struct temp_sensor_data *ts_data;
565 	struct temp_sensor_registers *tsr;
566 	u32 adc_val;
567 	int ret;
568 
569 	ret = ti_bandgap_validate(bgp, id);
570 	if (ret)
571 		return ret;
572 
573 	if (!TI_BANDGAP_HAS(bgp, TALERT))
574 		return -ENOTSUPP;
575 
576 	ts_data = bgp->conf->sensors[id].ts_data;
577 	tsr = bgp->conf->sensors[id].registers;
578 	if (hot) {
579 		if (val < ts_data->min_temp + ts_data->hyst_val)
580 			ret = -EINVAL;
581 	} else {
582 		if (val > ts_data->max_temp + ts_data->hyst_val)
583 			ret = -EINVAL;
584 	}
585 
586 	if (ret)
587 		return ret;
588 
589 	ret = ti_bandgap_mcelsius_to_adc(bgp, val, &adc_val);
590 	if (ret < 0)
591 		return ret;
592 
593 	spin_lock(&bgp->lock);
594 	ret = ti_bandgap_update_alert_threshold(bgp, id, adc_val, hot);
595 	spin_unlock(&bgp->lock);
596 	return ret;
597 }
598 
599 /**
600  * _ti_bandgap_read_threshold() - helper to read TALERT t_cold or t_hot
601  * @bgp: struct ti_bandgap pointer
602  * @id: bandgap sensor id
603  * @val: value (mCelsius) of a threshold
604  * @hot: desired threshold to be read. true if threshold hot, false if
605  *       threshold cold
606  *
607  * It will fetch the required thresholds (hot and cold) for TALERT signal.
608  * This function can be used to read t_hot or t_cold, depending on @hot value.
609  * Call this function only if bandgap features HAS(TALERT).
610  *
611  * Return: 0 if no error, -ENOTSUPP if it has no TALERT support, or the
612  * corresponding error value if some operation fails.
613  */
614 static int _ti_bandgap_read_threshold(struct ti_bandgap *bgp, int id,
615 				      int *val, bool hot)
616 {
617 	struct temp_sensor_registers *tsr;
618 	u32 temp, mask;
619 	int ret = 0;
620 
621 	ret = ti_bandgap_validate(bgp, id);
622 	if (ret)
623 		goto exit;
624 
625 	if (!TI_BANDGAP_HAS(bgp, TALERT)) {
626 		ret = -ENOTSUPP;
627 		goto exit;
628 	}
629 
630 	tsr = bgp->conf->sensors[id].registers;
631 	if (hot)
632 		mask = tsr->threshold_thot_mask;
633 	else
634 		mask = tsr->threshold_tcold_mask;
635 
636 	temp = ti_bandgap_readl(bgp, tsr->bgap_threshold);
637 	temp = (temp & mask) >> __ffs(mask);
638 	ret = ti_bandgap_adc_to_mcelsius(bgp, temp, &temp);
639 	if (ret) {
640 		dev_err(bgp->dev, "failed to read thot\n");
641 		ret = -EIO;
642 		goto exit;
643 	}
644 
645 	*val = temp;
646 
647 exit:
648 	return ret;
649 }
650 
651 /***   Exposed APIs   ***/
652 
653 /**
654  * ti_bandgap_read_thot() - reads sensor current thot
655  * @bgp: pointer to bandgap instance
656  * @id: sensor id
657  * @thot: resulting current thot value
658  *
659  * Return: 0 on success or the proper error code
660  */
661 int ti_bandgap_read_thot(struct ti_bandgap *bgp, int id, int *thot)
662 {
663 	return _ti_bandgap_read_threshold(bgp, id, thot, true);
664 }
665 
666 /**
667  * ti_bandgap_write_thot() - sets sensor current thot
668  * @bgp: pointer to bandgap instance
669  * @id: sensor id
670  * @val: desired thot value
671  *
672  * Return: 0 on success or the proper error code
673  */
674 int ti_bandgap_write_thot(struct ti_bandgap *bgp, int id, int val)
675 {
676 	return _ti_bandgap_write_threshold(bgp, id, val, true);
677 }
678 
679 /**
680  * ti_bandgap_read_tcold() - reads sensor current tcold
681  * @bgp: pointer to bandgap instance
682  * @id: sensor id
683  * @tcold: resulting current tcold value
684  *
685  * Return: 0 on success or the proper error code
686  */
687 int ti_bandgap_read_tcold(struct ti_bandgap *bgp, int id, int *tcold)
688 {
689 	return _ti_bandgap_read_threshold(bgp, id, tcold, false);
690 }
691 
692 /**
693  * ti_bandgap_write_tcold() - sets the sensor tcold
694  * @bgp: pointer to bandgap instance
695  * @id: sensor id
696  * @val: desired tcold value
697  *
698  * Return: 0 on success or the proper error code
699  */
700 int ti_bandgap_write_tcold(struct ti_bandgap *bgp, int id, int val)
701 {
702 	return _ti_bandgap_write_threshold(bgp, id, val, false);
703 }
704 
705 /**
706  * ti_bandgap_read_counter() - read the sensor counter
707  * @bgp: pointer to bandgap instance
708  * @id: sensor id
709  * @interval: resulting update interval in miliseconds
710  */
711 static void ti_bandgap_read_counter(struct ti_bandgap *bgp, int id,
712 				    int *interval)
713 {
714 	struct temp_sensor_registers *tsr;
715 	int time;
716 
717 	tsr = bgp->conf->sensors[id].registers;
718 	time = ti_bandgap_readl(bgp, tsr->bgap_counter);
719 	time = (time & tsr->counter_mask) >>
720 					__ffs(tsr->counter_mask);
721 	time = time * 1000 / bgp->clk_rate;
722 	*interval = time;
723 }
724 
725 /**
726  * ti_bandgap_read_counter_delay() - read the sensor counter delay
727  * @bgp: pointer to bandgap instance
728  * @id: sensor id
729  * @interval: resulting update interval in miliseconds
730  */
731 static void ti_bandgap_read_counter_delay(struct ti_bandgap *bgp, int id,
732 					  int *interval)
733 {
734 	struct temp_sensor_registers *tsr;
735 	int reg_val;
736 
737 	tsr = bgp->conf->sensors[id].registers;
738 
739 	reg_val = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
740 	reg_val = (reg_val & tsr->mask_counter_delay_mask) >>
741 				__ffs(tsr->mask_counter_delay_mask);
742 	switch (reg_val) {
743 	case 0:
744 		*interval = 0;
745 		break;
746 	case 1:
747 		*interval = 1;
748 		break;
749 	case 2:
750 		*interval = 10;
751 		break;
752 	case 3:
753 		*interval = 100;
754 		break;
755 	case 4:
756 		*interval = 250;
757 		break;
758 	case 5:
759 		*interval = 500;
760 		break;
761 	default:
762 		dev_warn(bgp->dev, "Wrong counter delay value read from register %X",
763 			 reg_val);
764 	}
765 }
766 
767 /**
768  * ti_bandgap_read_update_interval() - read the sensor update interval
769  * @bgp: pointer to bandgap instance
770  * @id: sensor id
771  * @interval: resulting update interval in miliseconds
772  *
773  * Return: 0 on success or the proper error code
774  */
775 int ti_bandgap_read_update_interval(struct ti_bandgap *bgp, int id,
776 				    int *interval)
777 {
778 	int ret = 0;
779 
780 	ret = ti_bandgap_validate(bgp, id);
781 	if (ret)
782 		goto exit;
783 
784 	if (!TI_BANDGAP_HAS(bgp, COUNTER) &&
785 	    !TI_BANDGAP_HAS(bgp, COUNTER_DELAY)) {
786 		ret = -ENOTSUPP;
787 		goto exit;
788 	}
789 
790 	if (TI_BANDGAP_HAS(bgp, COUNTER)) {
791 		ti_bandgap_read_counter(bgp, id, interval);
792 		goto exit;
793 	}
794 
795 	ti_bandgap_read_counter_delay(bgp, id, interval);
796 exit:
797 	return ret;
798 }
799 
800 /**
801  * ti_bandgap_write_counter_delay() - set the counter_delay
802  * @bgp: pointer to bandgap instance
803  * @id: sensor id
804  * @interval: desired update interval in miliseconds
805  *
806  * Return: 0 on success or the proper error code
807  */
808 static int ti_bandgap_write_counter_delay(struct ti_bandgap *bgp, int id,
809 					  u32 interval)
810 {
811 	int rval;
812 
813 	switch (interval) {
814 	case 0: /* Immediate conversion */
815 		rval = 0x0;
816 		break;
817 	case 1: /* Conversion after ever 1ms */
818 		rval = 0x1;
819 		break;
820 	case 10: /* Conversion after ever 10ms */
821 		rval = 0x2;
822 		break;
823 	case 100: /* Conversion after ever 100ms */
824 		rval = 0x3;
825 		break;
826 	case 250: /* Conversion after ever 250ms */
827 		rval = 0x4;
828 		break;
829 	case 500: /* Conversion after ever 500ms */
830 		rval = 0x5;
831 		break;
832 	default:
833 		dev_warn(bgp->dev, "Delay %d ms is not supported\n", interval);
834 		return -EINVAL;
835 	}
836 
837 	spin_lock(&bgp->lock);
838 	RMW_BITS(bgp, id, bgap_mask_ctrl, mask_counter_delay_mask, rval);
839 	spin_unlock(&bgp->lock);
840 
841 	return 0;
842 }
843 
844 /**
845  * ti_bandgap_write_counter() - set the bandgap sensor counter
846  * @bgp: pointer to bandgap instance
847  * @id: sensor id
848  * @interval: desired update interval in miliseconds
849  */
850 static void ti_bandgap_write_counter(struct ti_bandgap *bgp, int id,
851 				     u32 interval)
852 {
853 	interval = interval * bgp->clk_rate / 1000;
854 	spin_lock(&bgp->lock);
855 	RMW_BITS(bgp, id, bgap_counter, counter_mask, interval);
856 	spin_unlock(&bgp->lock);
857 }
858 
859 /**
860  * ti_bandgap_write_update_interval() - set the update interval
861  * @bgp: pointer to bandgap instance
862  * @id: sensor id
863  * @interval: desired update interval in miliseconds
864  *
865  * Return: 0 on success or the proper error code
866  */
867 int ti_bandgap_write_update_interval(struct ti_bandgap *bgp,
868 				     int id, u32 interval)
869 {
870 	int ret = ti_bandgap_validate(bgp, id);
871 	if (ret)
872 		goto exit;
873 
874 	if (!TI_BANDGAP_HAS(bgp, COUNTER) &&
875 	    !TI_BANDGAP_HAS(bgp, COUNTER_DELAY)) {
876 		ret = -ENOTSUPP;
877 		goto exit;
878 	}
879 
880 	if (TI_BANDGAP_HAS(bgp, COUNTER)) {
881 		ti_bandgap_write_counter(bgp, id, interval);
882 		goto exit;
883 	}
884 
885 	ret = ti_bandgap_write_counter_delay(bgp, id, interval);
886 exit:
887 	return ret;
888 }
889 
890 /**
891  * ti_bandgap_read_temperature() - report current temperature
892  * @bgp: pointer to bandgap instance
893  * @id: sensor id
894  * @temperature: resulting temperature
895  *
896  * Return: 0 on success or the proper error code
897  */
898 int ti_bandgap_read_temperature(struct ti_bandgap *bgp, int id,
899 				int *temperature)
900 {
901 	u32 temp;
902 	int ret;
903 
904 	ret = ti_bandgap_validate(bgp, id);
905 	if (ret)
906 		return ret;
907 
908 	if (!TI_BANDGAP_HAS(bgp, MODE_CONFIG)) {
909 		ret = ti_bandgap_force_single_read(bgp, id);
910 		if (ret)
911 			return ret;
912 	}
913 
914 	spin_lock(&bgp->lock);
915 	temp = ti_bandgap_read_temp(bgp, id);
916 	spin_unlock(&bgp->lock);
917 
918 	ret = ti_bandgap_adc_to_mcelsius(bgp, temp, &temp);
919 	if (ret)
920 		return -EIO;
921 
922 	*temperature = temp;
923 
924 	return 0;
925 }
926 
927 /**
928  * ti_bandgap_set_sensor_data() - helper function to store thermal
929  * framework related data.
930  * @bgp: pointer to bandgap instance
931  * @id: sensor id
932  * @data: thermal framework related data to be stored
933  *
934  * Return: 0 on success or the proper error code
935  */
936 int ti_bandgap_set_sensor_data(struct ti_bandgap *bgp, int id, void *data)
937 {
938 	int ret = ti_bandgap_validate(bgp, id);
939 	if (ret)
940 		return ret;
941 
942 	bgp->regval[id].data = data;
943 
944 	return 0;
945 }
946 
947 /**
948  * ti_bandgap_get_sensor_data() - helper function to get thermal
949  * framework related data.
950  * @bgp: pointer to bandgap instance
951  * @id: sensor id
952  *
953  * Return: data stored by set function with sensor id on success or NULL
954  */
955 void *ti_bandgap_get_sensor_data(struct ti_bandgap *bgp, int id)
956 {
957 	int ret = ti_bandgap_validate(bgp, id);
958 	if (ret)
959 		return ERR_PTR(ret);
960 
961 	return bgp->regval[id].data;
962 }
963 
964 /***   Helper functions used during device initialization   ***/
965 
966 /**
967  * ti_bandgap_force_single_read() - executes 1 single ADC conversion
968  * @bgp: pointer to struct ti_bandgap
969  * @id: sensor id which it is desired to read 1 temperature
970  *
971  * Used to initialize the conversion state machine and set it to a valid
972  * state. Called during device initialization and context restore events.
973  *
974  * Return: 0
975  */
976 static int
977 ti_bandgap_force_single_read(struct ti_bandgap *bgp, int id)
978 {
979 	u32 counter = 1000;
980 	struct temp_sensor_registers *tsr;
981 
982 	/* Select single conversion mode */
983 	if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
984 		RMW_BITS(bgp, id, bgap_mode_ctrl, mode_ctrl_mask, 0);
985 
986 	/* Start of Conversion = 1 */
987 	RMW_BITS(bgp, id, temp_sensor_ctrl, bgap_soc_mask, 1);
988 
989 	/* Wait for EOCZ going up */
990 	tsr = bgp->conf->sensors[id].registers;
991 
992 	while (--counter) {
993 		if (ti_bandgap_readl(bgp, tsr->temp_sensor_ctrl) &
994 		    tsr->bgap_eocz_mask)
995 			break;
996 	}
997 
998 	/* Start of Conversion = 0 */
999 	RMW_BITS(bgp, id, temp_sensor_ctrl, bgap_soc_mask, 0);
1000 
1001 	/* Wait for EOCZ going down */
1002 	counter = 1000;
1003 	while (--counter) {
1004 		if (!(ti_bandgap_readl(bgp, tsr->temp_sensor_ctrl) &
1005 		      tsr->bgap_eocz_mask))
1006 			break;
1007 	}
1008 
1009 	return 0;
1010 }
1011 
1012 /**
1013  * ti_bandgap_set_continous_mode() - One time enabling of continuous mode
1014  * @bgp: pointer to struct ti_bandgap
1015  *
1016  * Call this function only if HAS(MODE_CONFIG) is set. As this driver may
1017  * be used for junction temperature monitoring, it is desirable that the
1018  * sensors are operational all the time, so that alerts are generated
1019  * properly.
1020  *
1021  * Return: 0
1022  */
1023 static int ti_bandgap_set_continuous_mode(struct ti_bandgap *bgp)
1024 {
1025 	int i;
1026 
1027 	for (i = 0; i < bgp->conf->sensor_count; i++) {
1028 		/* Perform a single read just before enabling continuous */
1029 		ti_bandgap_force_single_read(bgp, i);
1030 		RMW_BITS(bgp, i, bgap_mode_ctrl, mode_ctrl_mask, 1);
1031 	}
1032 
1033 	return 0;
1034 }
1035 
1036 /**
1037  * ti_bandgap_get_trend() - To fetch the temperature trend of a sensor
1038  * @bgp: pointer to struct ti_bandgap
1039  * @id: id of the individual sensor
1040  * @trend: Pointer to trend.
1041  *
1042  * This function needs to be called to fetch the temperature trend of a
1043  * Particular sensor. The function computes the difference in temperature
1044  * w.r.t time. For the bandgaps with built in history buffer the temperatures
1045  * are read from the buffer and for those without the Buffer -ENOTSUPP is
1046  * returned.
1047  *
1048  * Return: 0 if no error, else return corresponding error. If no
1049  *		error then the trend value is passed on to trend parameter
1050  */
1051 int ti_bandgap_get_trend(struct ti_bandgap *bgp, int id, int *trend)
1052 {
1053 	struct temp_sensor_registers *tsr;
1054 	u32 temp1, temp2, reg1, reg2;
1055 	int t1, t2, interval, ret = 0;
1056 
1057 	ret = ti_bandgap_validate(bgp, id);
1058 	if (ret)
1059 		goto exit;
1060 
1061 	if (!TI_BANDGAP_HAS(bgp, HISTORY_BUFFER) ||
1062 	    !TI_BANDGAP_HAS(bgp, FREEZE_BIT)) {
1063 		ret = -ENOTSUPP;
1064 		goto exit;
1065 	}
1066 
1067 	spin_lock(&bgp->lock);
1068 
1069 	tsr = bgp->conf->sensors[id].registers;
1070 
1071 	/* Freeze and read the last 2 valid readings */
1072 	RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 1);
1073 	reg1 = tsr->ctrl_dtemp_1;
1074 	reg2 = tsr->ctrl_dtemp_2;
1075 
1076 	/* read temperature from history buffer */
1077 	temp1 = ti_bandgap_readl(bgp, reg1);
1078 	temp1 &= tsr->bgap_dtemp_mask;
1079 
1080 	temp2 = ti_bandgap_readl(bgp, reg2);
1081 	temp2 &= tsr->bgap_dtemp_mask;
1082 
1083 	/* Convert from adc values to mCelsius temperature */
1084 	ret = ti_bandgap_adc_to_mcelsius(bgp, temp1, &t1);
1085 	if (ret)
1086 		goto unfreeze;
1087 
1088 	ret = ti_bandgap_adc_to_mcelsius(bgp, temp2, &t2);
1089 	if (ret)
1090 		goto unfreeze;
1091 
1092 	/* Fetch the update interval */
1093 	ret = ti_bandgap_read_update_interval(bgp, id, &interval);
1094 	if (ret)
1095 		goto unfreeze;
1096 
1097 	/* Set the interval to 1 ms if bandgap counter delay is not set */
1098 	if (interval == 0)
1099 		interval = 1;
1100 
1101 	*trend = (t1 - t2) / interval;
1102 
1103 	dev_dbg(bgp->dev, "The temperatures are t1 = %d and t2 = %d and trend =%d\n",
1104 		t1, t2, *trend);
1105 
1106 unfreeze:
1107 	RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 0);
1108 	spin_unlock(&bgp->lock);
1109 exit:
1110 	return ret;
1111 }
1112 
1113 /**
1114  * ti_bandgap_tshut_init() - setup and initialize tshut handling
1115  * @bgp: pointer to struct ti_bandgap
1116  * @pdev: pointer to device struct platform_device
1117  *
1118  * Call this function only in case the bandgap features HAS(TSHUT).
1119  * In this case, the driver needs to handle the TSHUT signal as an IRQ.
1120  * The IRQ is wired as a GPIO, and for this purpose, it is required
1121  * to specify which GPIO line is used. TSHUT IRQ is fired anytime
1122  * one of the bandgap sensors violates the TSHUT high/hot threshold.
1123  * And in that case, the system must go off.
1124  *
1125  * Return: 0 if no error, else error status
1126  */
1127 static int ti_bandgap_tshut_init(struct ti_bandgap *bgp,
1128 				 struct platform_device *pdev)
1129 {
1130 	int gpio_nr = bgp->tshut_gpio;
1131 	int status;
1132 
1133 	/* Request for gpio_86 line */
1134 	status = gpio_request(gpio_nr, "tshut");
1135 	if (status < 0) {
1136 		dev_err(bgp->dev, "Could not request for TSHUT GPIO:%i\n", 86);
1137 		return status;
1138 	}
1139 	status = gpio_direction_input(gpio_nr);
1140 	if (status) {
1141 		dev_err(bgp->dev, "Cannot set input TSHUT GPIO %d\n", gpio_nr);
1142 		return status;
1143 	}
1144 
1145 	status = request_irq(gpio_to_irq(gpio_nr), ti_bandgap_tshut_irq_handler,
1146 			     IRQF_TRIGGER_RISING, "tshut", NULL);
1147 	if (status) {
1148 		gpio_free(gpio_nr);
1149 		dev_err(bgp->dev, "request irq failed for TSHUT");
1150 	}
1151 
1152 	return 0;
1153 }
1154 
1155 /**
1156  * ti_bandgap_alert_init() - setup and initialize talert handling
1157  * @bgp: pointer to struct ti_bandgap
1158  * @pdev: pointer to device struct platform_device
1159  *
1160  * Call this function only in case the bandgap features HAS(TALERT).
1161  * In this case, the driver needs to handle the TALERT signals as an IRQs.
1162  * TALERT is a normal IRQ and it is fired any time thresholds (hot or cold)
1163  * are violated. In these situation, the driver must reprogram the thresholds,
1164  * accordingly to specified policy.
1165  *
1166  * Return: 0 if no error, else return corresponding error.
1167  */
1168 static int ti_bandgap_talert_init(struct ti_bandgap *bgp,
1169 				  struct platform_device *pdev)
1170 {
1171 	int ret;
1172 
1173 	bgp->irq = platform_get_irq(pdev, 0);
1174 	if (bgp->irq < 0) {
1175 		dev_err(&pdev->dev, "get_irq failed\n");
1176 		return bgp->irq;
1177 	}
1178 	ret = request_threaded_irq(bgp->irq, NULL,
1179 				   ti_bandgap_talert_irq_handler,
1180 				   IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
1181 				   "talert", bgp);
1182 	if (ret) {
1183 		dev_err(&pdev->dev, "Request threaded irq failed.\n");
1184 		return ret;
1185 	}
1186 
1187 	return 0;
1188 }
1189 
1190 static const struct of_device_id of_ti_bandgap_match[];
1191 /**
1192  * ti_bandgap_build() - parse DT and setup a struct ti_bandgap
1193  * @pdev: pointer to device struct platform_device
1194  *
1195  * Used to read the device tree properties accordingly to the bandgap
1196  * matching version. Based on bandgap version and its capabilities it
1197  * will build a struct ti_bandgap out of the required DT entries.
1198  *
1199  * Return: valid bandgap structure if successful, else returns ERR_PTR
1200  * return value must be verified with IS_ERR.
1201  */
1202 static struct ti_bandgap *ti_bandgap_build(struct platform_device *pdev)
1203 {
1204 	struct device_node *node = pdev->dev.of_node;
1205 	const struct of_device_id *of_id;
1206 	struct ti_bandgap *bgp;
1207 	struct resource *res;
1208 	int i;
1209 
1210 	/* just for the sake */
1211 	if (!node) {
1212 		dev_err(&pdev->dev, "no platform information available\n");
1213 		return ERR_PTR(-EINVAL);
1214 	}
1215 
1216 	bgp = devm_kzalloc(&pdev->dev, sizeof(*bgp), GFP_KERNEL);
1217 	if (!bgp) {
1218 		dev_err(&pdev->dev, "Unable to allocate mem for driver ref\n");
1219 		return ERR_PTR(-ENOMEM);
1220 	}
1221 
1222 	of_id = of_match_device(of_ti_bandgap_match, &pdev->dev);
1223 	if (of_id)
1224 		bgp->conf = of_id->data;
1225 
1226 	/* register shadow for context save and restore */
1227 	bgp->regval = devm_kzalloc(&pdev->dev, sizeof(*bgp->regval) *
1228 				   bgp->conf->sensor_count, GFP_KERNEL);
1229 	if (!bgp->regval) {
1230 		dev_err(&pdev->dev, "Unable to allocate mem for driver ref\n");
1231 		return ERR_PTR(-ENOMEM);
1232 	}
1233 
1234 	i = 0;
1235 	do {
1236 		void __iomem *chunk;
1237 
1238 		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
1239 		if (!res)
1240 			break;
1241 		chunk = devm_ioremap_resource(&pdev->dev, res);
1242 		if (i == 0)
1243 			bgp->base = chunk;
1244 		if (IS_ERR(chunk))
1245 			return ERR_CAST(chunk);
1246 
1247 		i++;
1248 	} while (res);
1249 
1250 	if (TI_BANDGAP_HAS(bgp, TSHUT)) {
1251 		bgp->tshut_gpio = of_get_gpio(node, 0);
1252 		if (!gpio_is_valid(bgp->tshut_gpio)) {
1253 			dev_err(&pdev->dev, "invalid gpio for tshut (%d)\n",
1254 				bgp->tshut_gpio);
1255 			return ERR_PTR(-EINVAL);
1256 		}
1257 	}
1258 
1259 	return bgp;
1260 }
1261 
1262 /***   Device driver call backs   ***/
1263 
1264 static
1265 int ti_bandgap_probe(struct platform_device *pdev)
1266 {
1267 	struct ti_bandgap *bgp;
1268 	int clk_rate, ret = 0, i;
1269 
1270 	bgp = ti_bandgap_build(pdev);
1271 	if (IS_ERR(bgp)) {
1272 		dev_err(&pdev->dev, "failed to fetch platform data\n");
1273 		return PTR_ERR(bgp);
1274 	}
1275 	bgp->dev = &pdev->dev;
1276 
1277 	if (TI_BANDGAP_HAS(bgp, TSHUT)) {
1278 		ret = ti_bandgap_tshut_init(bgp, pdev);
1279 		if (ret) {
1280 			dev_err(&pdev->dev,
1281 				"failed to initialize system tshut IRQ\n");
1282 			return ret;
1283 		}
1284 	}
1285 
1286 	bgp->fclock = clk_get(NULL, bgp->conf->fclock_name);
1287 	ret = IS_ERR(bgp->fclock);
1288 	if (ret) {
1289 		dev_err(&pdev->dev, "failed to request fclock reference\n");
1290 		ret = PTR_ERR(bgp->fclock);
1291 		goto free_irqs;
1292 	}
1293 
1294 	bgp->div_clk = clk_get(NULL, bgp->conf->div_ck_name);
1295 	ret = IS_ERR(bgp->div_clk);
1296 	if (ret) {
1297 		dev_err(&pdev->dev, "failed to request div_ts_ck clock ref\n");
1298 		ret = PTR_ERR(bgp->div_clk);
1299 		goto free_irqs;
1300 	}
1301 
1302 	for (i = 0; i < bgp->conf->sensor_count; i++) {
1303 		struct temp_sensor_registers *tsr;
1304 		u32 val;
1305 
1306 		tsr = bgp->conf->sensors[i].registers;
1307 		/*
1308 		 * check if the efuse has a non-zero value if not
1309 		 * it is an untrimmed sample and the temperatures
1310 		 * may not be accurate
1311 		 */
1312 		val = ti_bandgap_readl(bgp, tsr->bgap_efuse);
1313 		if (ret || !val)
1314 			dev_info(&pdev->dev,
1315 				 "Non-trimmed BGAP, Temp not accurate\n");
1316 	}
1317 
1318 	clk_rate = clk_round_rate(bgp->div_clk,
1319 				  bgp->conf->sensors[0].ts_data->max_freq);
1320 	if (clk_rate < bgp->conf->sensors[0].ts_data->min_freq ||
1321 	    clk_rate <= 0) {
1322 		ret = -ENODEV;
1323 		dev_err(&pdev->dev, "wrong clock rate (%d)\n", clk_rate);
1324 		goto put_clks;
1325 	}
1326 
1327 	ret = clk_set_rate(bgp->div_clk, clk_rate);
1328 	if (ret)
1329 		dev_err(&pdev->dev, "Cannot re-set clock rate. Continuing\n");
1330 
1331 	bgp->clk_rate = clk_rate;
1332 	if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1333 		clk_prepare_enable(bgp->fclock);
1334 
1335 
1336 	spin_lock_init(&bgp->lock);
1337 	bgp->dev = &pdev->dev;
1338 	platform_set_drvdata(pdev, bgp);
1339 
1340 	ti_bandgap_power(bgp, true);
1341 
1342 	/* Set default counter to 1 for now */
1343 	if (TI_BANDGAP_HAS(bgp, COUNTER))
1344 		for (i = 0; i < bgp->conf->sensor_count; i++)
1345 			RMW_BITS(bgp, i, bgap_counter, counter_mask, 1);
1346 
1347 	/* Set default thresholds for alert and shutdown */
1348 	for (i = 0; i < bgp->conf->sensor_count; i++) {
1349 		struct temp_sensor_data *ts_data;
1350 
1351 		ts_data = bgp->conf->sensors[i].ts_data;
1352 
1353 		if (TI_BANDGAP_HAS(bgp, TALERT)) {
1354 			/* Set initial Talert thresholds */
1355 			RMW_BITS(bgp, i, bgap_threshold,
1356 				 threshold_tcold_mask, ts_data->t_cold);
1357 			RMW_BITS(bgp, i, bgap_threshold,
1358 				 threshold_thot_mask, ts_data->t_hot);
1359 			/* Enable the alert events */
1360 			RMW_BITS(bgp, i, bgap_mask_ctrl, mask_hot_mask, 1);
1361 			RMW_BITS(bgp, i, bgap_mask_ctrl, mask_cold_mask, 1);
1362 		}
1363 
1364 		if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG)) {
1365 			/* Set initial Tshut thresholds */
1366 			RMW_BITS(bgp, i, tshut_threshold,
1367 				 tshut_hot_mask, ts_data->tshut_hot);
1368 			RMW_BITS(bgp, i, tshut_threshold,
1369 				 tshut_cold_mask, ts_data->tshut_cold);
1370 		}
1371 	}
1372 
1373 	if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
1374 		ti_bandgap_set_continuous_mode(bgp);
1375 
1376 	/* Set .250 seconds time as default counter */
1377 	if (TI_BANDGAP_HAS(bgp, COUNTER))
1378 		for (i = 0; i < bgp->conf->sensor_count; i++)
1379 			RMW_BITS(bgp, i, bgap_counter, counter_mask,
1380 				 bgp->clk_rate / 4);
1381 
1382 	/* Every thing is good? Then expose the sensors */
1383 	for (i = 0; i < bgp->conf->sensor_count; i++) {
1384 		char *domain;
1385 
1386 		if (bgp->conf->sensors[i].register_cooling) {
1387 			ret = bgp->conf->sensors[i].register_cooling(bgp, i);
1388 			if (ret)
1389 				goto remove_sensors;
1390 		}
1391 
1392 		if (bgp->conf->expose_sensor) {
1393 			domain = bgp->conf->sensors[i].domain;
1394 			ret = bgp->conf->expose_sensor(bgp, i, domain);
1395 			if (ret)
1396 				goto remove_last_cooling;
1397 		}
1398 	}
1399 
1400 	/*
1401 	 * Enable the Interrupts once everything is set. Otherwise irq handler
1402 	 * might be called as soon as it is enabled where as rest of framework
1403 	 * is still getting initialised.
1404 	 */
1405 	if (TI_BANDGAP_HAS(bgp, TALERT)) {
1406 		ret = ti_bandgap_talert_init(bgp, pdev);
1407 		if (ret) {
1408 			dev_err(&pdev->dev, "failed to initialize Talert IRQ\n");
1409 			i = bgp->conf->sensor_count;
1410 			goto disable_clk;
1411 		}
1412 	}
1413 
1414 	return 0;
1415 
1416 remove_last_cooling:
1417 	if (bgp->conf->sensors[i].unregister_cooling)
1418 		bgp->conf->sensors[i].unregister_cooling(bgp, i);
1419 remove_sensors:
1420 	for (i--; i >= 0; i--) {
1421 		if (bgp->conf->sensors[i].unregister_cooling)
1422 			bgp->conf->sensors[i].unregister_cooling(bgp, i);
1423 		if (bgp->conf->remove_sensor)
1424 			bgp->conf->remove_sensor(bgp, i);
1425 	}
1426 	ti_bandgap_power(bgp, false);
1427 disable_clk:
1428 	if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1429 		clk_disable_unprepare(bgp->fclock);
1430 put_clks:
1431 	clk_put(bgp->fclock);
1432 	clk_put(bgp->div_clk);
1433 free_irqs:
1434 	if (TI_BANDGAP_HAS(bgp, TSHUT)) {
1435 		free_irq(gpio_to_irq(bgp->tshut_gpio), NULL);
1436 		gpio_free(bgp->tshut_gpio);
1437 	}
1438 
1439 	return ret;
1440 }
1441 
1442 static
1443 int ti_bandgap_remove(struct platform_device *pdev)
1444 {
1445 	struct ti_bandgap *bgp = platform_get_drvdata(pdev);
1446 	int i;
1447 
1448 	/* First thing is to remove sensor interfaces */
1449 	for (i = 0; i < bgp->conf->sensor_count; i++) {
1450 		if (bgp->conf->sensors[i].unregister_cooling)
1451 			bgp->conf->sensors[i].unregister_cooling(bgp, i);
1452 
1453 		if (bgp->conf->remove_sensor)
1454 			bgp->conf->remove_sensor(bgp, i);
1455 	}
1456 
1457 	ti_bandgap_power(bgp, false);
1458 
1459 	if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1460 		clk_disable_unprepare(bgp->fclock);
1461 	clk_put(bgp->fclock);
1462 	clk_put(bgp->div_clk);
1463 
1464 	if (TI_BANDGAP_HAS(bgp, TALERT))
1465 		free_irq(bgp->irq, bgp);
1466 
1467 	if (TI_BANDGAP_HAS(bgp, TSHUT)) {
1468 		free_irq(gpio_to_irq(bgp->tshut_gpio), NULL);
1469 		gpio_free(bgp->tshut_gpio);
1470 	}
1471 
1472 	return 0;
1473 }
1474 
1475 #ifdef CONFIG_PM_SLEEP
1476 static int ti_bandgap_save_ctxt(struct ti_bandgap *bgp)
1477 {
1478 	int i;
1479 
1480 	for (i = 0; i < bgp->conf->sensor_count; i++) {
1481 		struct temp_sensor_registers *tsr;
1482 		struct temp_sensor_regval *rval;
1483 
1484 		rval = &bgp->regval[i];
1485 		tsr = bgp->conf->sensors[i].registers;
1486 
1487 		if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
1488 			rval->bg_mode_ctrl = ti_bandgap_readl(bgp,
1489 							tsr->bgap_mode_ctrl);
1490 		if (TI_BANDGAP_HAS(bgp, COUNTER))
1491 			rval->bg_counter = ti_bandgap_readl(bgp,
1492 							tsr->bgap_counter);
1493 		if (TI_BANDGAP_HAS(bgp, TALERT)) {
1494 			rval->bg_threshold = ti_bandgap_readl(bgp,
1495 							tsr->bgap_threshold);
1496 			rval->bg_ctrl = ti_bandgap_readl(bgp,
1497 						   tsr->bgap_mask_ctrl);
1498 		}
1499 
1500 		if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG))
1501 			rval->tshut_threshold = ti_bandgap_readl(bgp,
1502 						   tsr->tshut_threshold);
1503 	}
1504 
1505 	return 0;
1506 }
1507 
1508 static int ti_bandgap_restore_ctxt(struct ti_bandgap *bgp)
1509 {
1510 	int i;
1511 
1512 	for (i = 0; i < bgp->conf->sensor_count; i++) {
1513 		struct temp_sensor_registers *tsr;
1514 		struct temp_sensor_regval *rval;
1515 		u32 val = 0;
1516 
1517 		rval = &bgp->regval[i];
1518 		tsr = bgp->conf->sensors[i].registers;
1519 
1520 		if (TI_BANDGAP_HAS(bgp, COUNTER))
1521 			val = ti_bandgap_readl(bgp, tsr->bgap_counter);
1522 
1523 		if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG))
1524 			ti_bandgap_writel(bgp, rval->tshut_threshold,
1525 					  tsr->tshut_threshold);
1526 		/* Force immediate temperature measurement and update
1527 		 * of the DTEMP field
1528 		 */
1529 		ti_bandgap_force_single_read(bgp, i);
1530 
1531 		if (TI_BANDGAP_HAS(bgp, COUNTER))
1532 			ti_bandgap_writel(bgp, rval->bg_counter,
1533 					  tsr->bgap_counter);
1534 		if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
1535 			ti_bandgap_writel(bgp, rval->bg_mode_ctrl,
1536 					  tsr->bgap_mode_ctrl);
1537 		if (TI_BANDGAP_HAS(bgp, TALERT)) {
1538 			ti_bandgap_writel(bgp, rval->bg_threshold,
1539 					  tsr->bgap_threshold);
1540 			ti_bandgap_writel(bgp, rval->bg_ctrl,
1541 					  tsr->bgap_mask_ctrl);
1542 		}
1543 	}
1544 
1545 	return 0;
1546 }
1547 
1548 static int ti_bandgap_suspend(struct device *dev)
1549 {
1550 	struct ti_bandgap *bgp = dev_get_drvdata(dev);
1551 	int err;
1552 
1553 	err = ti_bandgap_save_ctxt(bgp);
1554 	ti_bandgap_power(bgp, false);
1555 
1556 	if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1557 		clk_disable_unprepare(bgp->fclock);
1558 
1559 	return err;
1560 }
1561 
1562 static int ti_bandgap_resume(struct device *dev)
1563 {
1564 	struct ti_bandgap *bgp = dev_get_drvdata(dev);
1565 
1566 	if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1567 		clk_prepare_enable(bgp->fclock);
1568 
1569 	ti_bandgap_power(bgp, true);
1570 
1571 	return ti_bandgap_restore_ctxt(bgp);
1572 }
1573 static SIMPLE_DEV_PM_OPS(ti_bandgap_dev_pm_ops, ti_bandgap_suspend,
1574 			 ti_bandgap_resume);
1575 
1576 #define DEV_PM_OPS	(&ti_bandgap_dev_pm_ops)
1577 #else
1578 #define DEV_PM_OPS	NULL
1579 #endif
1580 
1581 static const struct of_device_id of_ti_bandgap_match[] = {
1582 #ifdef CONFIG_OMAP4_THERMAL
1583 	{
1584 		.compatible = "ti,omap4430-bandgap",
1585 		.data = (void *)&omap4430_data,
1586 	},
1587 	{
1588 		.compatible = "ti,omap4460-bandgap",
1589 		.data = (void *)&omap4460_data,
1590 	},
1591 	{
1592 		.compatible = "ti,omap4470-bandgap",
1593 		.data = (void *)&omap4470_data,
1594 	},
1595 #endif
1596 #ifdef CONFIG_OMAP5_THERMAL
1597 	{
1598 		.compatible = "ti,omap5430-bandgap",
1599 		.data = (void *)&omap5430_data,
1600 	},
1601 #endif
1602 #ifdef CONFIG_DRA752_THERMAL
1603 	{
1604 		.compatible = "ti,dra752-bandgap",
1605 		.data = (void *)&dra752_data,
1606 	},
1607 #endif
1608 	/* Sentinel */
1609 	{ },
1610 };
1611 MODULE_DEVICE_TABLE(of, of_ti_bandgap_match);
1612 
1613 static struct platform_driver ti_bandgap_sensor_driver = {
1614 	.probe = ti_bandgap_probe,
1615 	.remove = ti_bandgap_remove,
1616 	.driver = {
1617 			.name = "ti-soc-thermal",
1618 			.pm = DEV_PM_OPS,
1619 			.of_match_table	= of_ti_bandgap_match,
1620 	},
1621 };
1622 
1623 module_platform_driver(ti_bandgap_sensor_driver);
1624 
1625 MODULE_DESCRIPTION("OMAP4+ bandgap temperature sensor driver");
1626 MODULE_LICENSE("GPL v2");
1627 MODULE_ALIAS("platform:ti-soc-thermal");
1628 MODULE_AUTHOR("Texas Instrument Inc.");
1629