1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * TI Bandgap temperature sensor driver
4 *
5 * Copyright (C) 2011-2012 Texas Instruments Incorporated - http://www.ti.com/
6 * Author: J Keerthy <j-keerthy@ti.com>
7 * Author: Moiz Sonasath <m-sonasath@ti.com>
8 * Couple of fixes, DT and MFD adaptation:
9 * Eduardo Valentin <eduardo.valentin@ti.com>
10 */
11
12#include <linux/clk.h>
13#include <linux/cpu_pm.h>
14#include <linux/device.h>
15#include <linux/err.h>
16#include <linux/export.h>
17#include <linux/gpio/consumer.h>
18#include <linux/init.h>
19#include <linux/interrupt.h>
20#include <linux/io.h>
21#include <linux/iopoll.h>
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/of.h>
25#include <linux/of_device.h>
26#include <linux/of_irq.h>
27#include <linux/of_platform.h>
28#include <linux/platform_device.h>
29#include <linux/pm.h>
30#include <linux/pm_runtime.h>
31#include <linux/reboot.h>
32#include <linux/spinlock.h>
33#include <linux/sys_soc.h>
34#include <linux/types.h>
35
36#include "ti-bandgap.h"
37
38static int ti_bandgap_force_single_read(struct ti_bandgap *bgp, int id);
39#ifdef CONFIG_PM_SLEEP
40static int bandgap_omap_cpu_notifier(struct notifier_block *nb,
41 unsigned long cmd, void *v);
42#endif
43
44/*** Helper functions to access registers and their bitfields ***/
45
46/**
47 * ti_bandgap_readl() - simple read helper function
48 * @bgp: pointer to ti_bandgap structure
49 * @reg: desired register (offset) to be read
50 *
51 * Helper function to read bandgap registers. It uses the io remapped area.
52 * Return: the register value.
53 */
54static u32 ti_bandgap_readl(struct ti_bandgap *bgp, u32 reg)
55{
56 return readl(addr: bgp->base + reg);
57}
58
59/**
60 * ti_bandgap_writel() - simple write helper function
61 * @bgp: pointer to ti_bandgap structure
62 * @val: desired register value to be written
63 * @reg: desired register (offset) to be written
64 *
65 * Helper function to write bandgap registers. It uses the io remapped area.
66 */
67static void ti_bandgap_writel(struct ti_bandgap *bgp, u32 val, u32 reg)
68{
69 writel(val, addr: bgp->base + reg);
70}
71
72/**
73 * DOC: macro to update bits.
74 *
75 * RMW_BITS() - used to read, modify and update bandgap bitfields.
76 * The value passed will be shifted.
77 */
78#define RMW_BITS(bgp, id, reg, mask, val) \
79do { \
80 struct temp_sensor_registers *t; \
81 u32 r; \
82 \
83 t = bgp->conf->sensors[(id)].registers; \
84 r = ti_bandgap_readl(bgp, t->reg); \
85 r &= ~t->mask; \
86 r |= (val) << __ffs(t->mask); \
87 ti_bandgap_writel(bgp, r, t->reg); \
88} while (0)
89
90/*** Basic helper functions ***/
91
92/**
93 * ti_bandgap_power() - controls the power state of a bandgap device
94 * @bgp: pointer to ti_bandgap structure
95 * @on: desired power state (1 - on, 0 - off)
96 *
97 * Used to power on/off a bandgap device instance. Only used on those
98 * that features tempsoff bit.
99 *
100 * Return: 0 on success, -ENOTSUPP if tempsoff is not supported.
101 */
102static int ti_bandgap_power(struct ti_bandgap *bgp, bool on)
103{
104 int i;
105
106 if (!TI_BANDGAP_HAS(bgp, POWER_SWITCH))
107 return -ENOTSUPP;
108
109 for (i = 0; i < bgp->conf->sensor_count; i++)
110 /* active on 0 */
111 RMW_BITS(bgp, i, temp_sensor_ctrl, bgap_tempsoff_mask, !on);
112 return 0;
113}
114
115/**
116 * ti_errata814_bandgap_read_temp() - helper function to read dra7 sensor temperature
117 * @bgp: pointer to ti_bandgap structure
118 * @reg: desired register (offset) to be read
119 *
120 * Function to read dra7 bandgap sensor temperature. This is done separately
121 * so as to workaround the errata "Bandgap Temperature read Dtemp can be
122 * corrupted" - Errata ID: i814".
123 * Read accesses to registers listed below can be corrupted due to incorrect
124 * resynchronization between clock domains.
125 * Read access to registers below can be corrupted :
126 * CTRL_CORE_DTEMP_MPU/GPU/CORE/DSPEVE/IVA_n (n = 0 to 4)
127 * CTRL_CORE_TEMP_SENSOR_MPU/GPU/CORE/DSPEVE/IVA_n
128 *
129 * Return: the register value.
130 */
131static u32 ti_errata814_bandgap_read_temp(struct ti_bandgap *bgp, u32 reg)
132{
133 u32 val1, val2;
134
135 val1 = ti_bandgap_readl(bgp, reg);
136 val2 = ti_bandgap_readl(bgp, reg);
137
138 /* If both times we read the same value then that is right */
139 if (val1 == val2)
140 return val1;
141
142 /* if val1 and val2 are different read it third time */
143 return ti_bandgap_readl(bgp, reg);
144}
145
146/**
147 * ti_bandgap_read_temp() - helper function to read sensor temperature
148 * @bgp: pointer to ti_bandgap structure
149 * @id: bandgap sensor id
150 *
151 * Function to concentrate the steps to read sensor temperature register.
152 * This function is desired because, depending on bandgap device version,
153 * it might be needed to freeze the bandgap state machine, before fetching
154 * the register value.
155 *
156 * Return: temperature in ADC values.
157 */
158static u32 ti_bandgap_read_temp(struct ti_bandgap *bgp, int id)
159{
160 struct temp_sensor_registers *tsr;
161 u32 temp, reg;
162
163 tsr = bgp->conf->sensors[id].registers;
164 reg = tsr->temp_sensor_ctrl;
165
166 if (TI_BANDGAP_HAS(bgp, FREEZE_BIT)) {
167 RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 1);
168 /*
169 * In case we cannot read from cur_dtemp / dtemp_0,
170 * then we read from the last valid temp read
171 */
172 reg = tsr->ctrl_dtemp_1;
173 }
174
175 /* read temperature */
176 if (TI_BANDGAP_HAS(bgp, ERRATA_814))
177 temp = ti_errata814_bandgap_read_temp(bgp, reg);
178 else
179 temp = ti_bandgap_readl(bgp, reg);
180
181 temp &= tsr->bgap_dtemp_mask;
182
183 if (TI_BANDGAP_HAS(bgp, FREEZE_BIT))
184 RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 0);
185
186 return temp;
187}
188
189/*** IRQ handlers ***/
190
191/**
192 * ti_bandgap_talert_irq_handler() - handles Temperature alert IRQs
193 * @irq: IRQ number
194 * @data: private data (struct ti_bandgap *)
195 *
196 * This is the Talert handler. Use it only if bandgap device features
197 * HAS(TALERT). This handler goes over all sensors and checks their
198 * conditions and acts accordingly. In case there are events pending,
199 * it will reset the event mask to wait for the opposite event (next event).
200 * Every time there is a new event, it will be reported to thermal layer.
201 *
202 * Return: IRQ_HANDLED
203 */
204static irqreturn_t ti_bandgap_talert_irq_handler(int irq, void *data)
205{
206 struct ti_bandgap *bgp = data;
207 struct temp_sensor_registers *tsr;
208 u32 t_hot = 0, t_cold = 0, ctrl;
209 int i;
210
211 spin_lock(lock: &bgp->lock);
212 for (i = 0; i < bgp->conf->sensor_count; i++) {
213 tsr = bgp->conf->sensors[i].registers;
214 ctrl = ti_bandgap_readl(bgp, reg: tsr->bgap_status);
215
216 /* Read the status of t_hot */
217 t_hot = ctrl & tsr->status_hot_mask;
218
219 /* Read the status of t_cold */
220 t_cold = ctrl & tsr->status_cold_mask;
221
222 if (!t_cold && !t_hot)
223 continue;
224
225 ctrl = ti_bandgap_readl(bgp, reg: tsr->bgap_mask_ctrl);
226 /*
227 * One TALERT interrupt: Two sources
228 * If the interrupt is due to t_hot then mask t_hot and
229 * unmask t_cold else mask t_cold and unmask t_hot
230 */
231 if (t_hot) {
232 ctrl &= ~tsr->mask_hot_mask;
233 ctrl |= tsr->mask_cold_mask;
234 } else if (t_cold) {
235 ctrl &= ~tsr->mask_cold_mask;
236 ctrl |= tsr->mask_hot_mask;
237 }
238
239 ti_bandgap_writel(bgp, val: ctrl, reg: tsr->bgap_mask_ctrl);
240
241 dev_dbg(bgp->dev,
242 "%s: IRQ from %s sensor: hotevent %d coldevent %d\n",
243 __func__, bgp->conf->sensors[i].domain,
244 t_hot, t_cold);
245
246 /* report temperature to whom may concern */
247 if (bgp->conf->report_temperature)
248 bgp->conf->report_temperature(bgp, i);
249 }
250 spin_unlock(lock: &bgp->lock);
251
252 return IRQ_HANDLED;
253}
254
255/**
256 * ti_bandgap_tshut_irq_handler() - handles Temperature shutdown signal
257 * @irq: IRQ number
258 * @data: private data (unused)
259 *
260 * This is the Tshut handler. Use it only if bandgap device features
261 * HAS(TSHUT). If any sensor fires the Tshut signal, we simply shutdown
262 * the system.
263 *
264 * Return: IRQ_HANDLED
265 */
266static irqreturn_t ti_bandgap_tshut_irq_handler(int irq, void *data)
267{
268 pr_emerg("%s: TSHUT temperature reached. Needs shut down...\n",
269 __func__);
270
271 orderly_poweroff(force: true);
272
273 return IRQ_HANDLED;
274}
275
276/*** Helper functions which manipulate conversion ADC <-> mi Celsius ***/
277
278/**
279 * ti_bandgap_adc_to_mcelsius() - converts an ADC value to mCelsius scale
280 * @bgp: struct ti_bandgap pointer
281 * @adc_val: value in ADC representation
282 * @t: address where to write the resulting temperature in mCelsius
283 *
284 * Simple conversion from ADC representation to mCelsius. In case the ADC value
285 * is out of the ADC conv table range, it returns -ERANGE, 0 on success.
286 * The conversion table is indexed by the ADC values.
287 *
288 * Return: 0 if conversion was successful, else -ERANGE in case the @adc_val
289 * argument is out of the ADC conv table range.
290 */
291static
292int ti_bandgap_adc_to_mcelsius(struct ti_bandgap *bgp, int adc_val, int *t)
293{
294 const struct ti_bandgap_data *conf = bgp->conf;
295
296 /* look up for temperature in the table and return the temperature */
297 if (adc_val < conf->adc_start_val || adc_val > conf->adc_end_val)
298 return -ERANGE;
299
300 *t = bgp->conf->conv_table[adc_val - conf->adc_start_val];
301 return 0;
302}
303
304/**
305 * ti_bandgap_validate() - helper to check the sanity of a struct ti_bandgap
306 * @bgp: struct ti_bandgap pointer
307 * @id: bandgap sensor id
308 *
309 * Checks if the bandgap pointer is valid and if the sensor id is also
310 * applicable.
311 *
312 * Return: 0 if no errors, -EINVAL for invalid @bgp pointer or -ERANGE if
313 * @id cannot index @bgp sensors.
314 */
315static inline int ti_bandgap_validate(struct ti_bandgap *bgp, int id)
316{
317 if (IS_ERR_OR_NULL(ptr: bgp)) {
318 pr_err("%s: invalid bandgap pointer\n", __func__);
319 return -EINVAL;
320 }
321
322 if ((id < 0) || (id >= bgp->conf->sensor_count)) {
323 dev_err(bgp->dev, "%s: sensor id out of range (%d)\n",
324 __func__, id);
325 return -ERANGE;
326 }
327
328 return 0;
329}
330
331/**
332 * ti_bandgap_read_counter() - read the sensor counter
333 * @bgp: pointer to bandgap instance
334 * @id: sensor id
335 * @interval: resulting update interval in miliseconds
336 */
337static void ti_bandgap_read_counter(struct ti_bandgap *bgp, int id,
338 int *interval)
339{
340 struct temp_sensor_registers *tsr;
341 int time;
342
343 tsr = bgp->conf->sensors[id].registers;
344 time = ti_bandgap_readl(bgp, reg: tsr->bgap_counter);
345 time = (time & tsr->counter_mask) >>
346 __ffs(tsr->counter_mask);
347 time = time * 1000 / bgp->clk_rate;
348 *interval = time;
349}
350
351/**
352 * ti_bandgap_read_counter_delay() - read the sensor counter delay
353 * @bgp: pointer to bandgap instance
354 * @id: sensor id
355 * @interval: resulting update interval in miliseconds
356 */
357static void ti_bandgap_read_counter_delay(struct ti_bandgap *bgp, int id,
358 int *interval)
359{
360 struct temp_sensor_registers *tsr;
361 int reg_val;
362
363 tsr = bgp->conf->sensors[id].registers;
364
365 reg_val = ti_bandgap_readl(bgp, reg: tsr->bgap_mask_ctrl);
366 reg_val = (reg_val & tsr->mask_counter_delay_mask) >>
367 __ffs(tsr->mask_counter_delay_mask);
368 switch (reg_val) {
369 case 0:
370 *interval = 0;
371 break;
372 case 1:
373 *interval = 1;
374 break;
375 case 2:
376 *interval = 10;
377 break;
378 case 3:
379 *interval = 100;
380 break;
381 case 4:
382 *interval = 250;
383 break;
384 case 5:
385 *interval = 500;
386 break;
387 default:
388 dev_warn(bgp->dev, "Wrong counter delay value read from register %X",
389 reg_val);
390 }
391}
392
393/**
394 * ti_bandgap_read_update_interval() - read the sensor update interval
395 * @bgp: pointer to bandgap instance
396 * @id: sensor id
397 * @interval: resulting update interval in miliseconds
398 *
399 * Return: 0 on success or the proper error code
400 */
401int ti_bandgap_read_update_interval(struct ti_bandgap *bgp, int id,
402 int *interval)
403{
404 int ret = 0;
405
406 ret = ti_bandgap_validate(bgp, id);
407 if (ret)
408 goto exit;
409
410 if (!TI_BANDGAP_HAS(bgp, COUNTER) &&
411 !TI_BANDGAP_HAS(bgp, COUNTER_DELAY)) {
412 ret = -ENOTSUPP;
413 goto exit;
414 }
415
416 if (TI_BANDGAP_HAS(bgp, COUNTER)) {
417 ti_bandgap_read_counter(bgp, id, interval);
418 goto exit;
419 }
420
421 ti_bandgap_read_counter_delay(bgp, id, interval);
422exit:
423 return ret;
424}
425
426/**
427 * ti_bandgap_write_counter_delay() - set the counter_delay
428 * @bgp: pointer to bandgap instance
429 * @id: sensor id
430 * @interval: desired update interval in miliseconds
431 *
432 * Return: 0 on success or the proper error code
433 */
434static int ti_bandgap_write_counter_delay(struct ti_bandgap *bgp, int id,
435 u32 interval)
436{
437 int rval;
438
439 switch (interval) {
440 case 0: /* Immediate conversion */
441 rval = 0x0;
442 break;
443 case 1: /* Conversion after ever 1ms */
444 rval = 0x1;
445 break;
446 case 10: /* Conversion after ever 10ms */
447 rval = 0x2;
448 break;
449 case 100: /* Conversion after ever 100ms */
450 rval = 0x3;
451 break;
452 case 250: /* Conversion after ever 250ms */
453 rval = 0x4;
454 break;
455 case 500: /* Conversion after ever 500ms */
456 rval = 0x5;
457 break;
458 default:
459 dev_warn(bgp->dev, "Delay %d ms is not supported\n", interval);
460 return -EINVAL;
461 }
462
463 spin_lock(lock: &bgp->lock);
464 RMW_BITS(bgp, id, bgap_mask_ctrl, mask_counter_delay_mask, rval);
465 spin_unlock(lock: &bgp->lock);
466
467 return 0;
468}
469
470/**
471 * ti_bandgap_write_counter() - set the bandgap sensor counter
472 * @bgp: pointer to bandgap instance
473 * @id: sensor id
474 * @interval: desired update interval in miliseconds
475 */
476static void ti_bandgap_write_counter(struct ti_bandgap *bgp, int id,
477 u32 interval)
478{
479 interval = interval * bgp->clk_rate / 1000;
480 spin_lock(lock: &bgp->lock);
481 RMW_BITS(bgp, id, bgap_counter, counter_mask, interval);
482 spin_unlock(lock: &bgp->lock);
483}
484
485/**
486 * ti_bandgap_write_update_interval() - set the update interval
487 * @bgp: pointer to bandgap instance
488 * @id: sensor id
489 * @interval: desired update interval in miliseconds
490 *
491 * Return: 0 on success or the proper error code
492 */
493int ti_bandgap_write_update_interval(struct ti_bandgap *bgp,
494 int id, u32 interval)
495{
496 int ret = ti_bandgap_validate(bgp, id);
497 if (ret)
498 goto exit;
499
500 if (!TI_BANDGAP_HAS(bgp, COUNTER) &&
501 !TI_BANDGAP_HAS(bgp, COUNTER_DELAY)) {
502 ret = -ENOTSUPP;
503 goto exit;
504 }
505
506 if (TI_BANDGAP_HAS(bgp, COUNTER)) {
507 ti_bandgap_write_counter(bgp, id, interval);
508 goto exit;
509 }
510
511 ret = ti_bandgap_write_counter_delay(bgp, id, interval);
512exit:
513 return ret;
514}
515
516/**
517 * ti_bandgap_read_temperature() - report current temperature
518 * @bgp: pointer to bandgap instance
519 * @id: sensor id
520 * @temperature: resulting temperature
521 *
522 * Return: 0 on success or the proper error code
523 */
524int ti_bandgap_read_temperature(struct ti_bandgap *bgp, int id,
525 int *temperature)
526{
527 u32 temp;
528 int ret;
529
530 ret = ti_bandgap_validate(bgp, id);
531 if (ret)
532 return ret;
533
534 if (!TI_BANDGAP_HAS(bgp, MODE_CONFIG)) {
535 ret = ti_bandgap_force_single_read(bgp, id);
536 if (ret)
537 return ret;
538 }
539
540 spin_lock(lock: &bgp->lock);
541 temp = ti_bandgap_read_temp(bgp, id);
542 spin_unlock(lock: &bgp->lock);
543
544 ret = ti_bandgap_adc_to_mcelsius(bgp, adc_val: temp, t: &temp);
545 if (ret)
546 return -EIO;
547
548 *temperature = temp;
549
550 return 0;
551}
552
553/**
554 * ti_bandgap_set_sensor_data() - helper function to store thermal
555 * framework related data.
556 * @bgp: pointer to bandgap instance
557 * @id: sensor id
558 * @data: thermal framework related data to be stored
559 *
560 * Return: 0 on success or the proper error code
561 */
562int ti_bandgap_set_sensor_data(struct ti_bandgap *bgp, int id, void *data)
563{
564 int ret = ti_bandgap_validate(bgp, id);
565 if (ret)
566 return ret;
567
568 bgp->regval[id].data = data;
569
570 return 0;
571}
572
573/**
574 * ti_bandgap_get_sensor_data() - helper function to get thermal
575 * framework related data.
576 * @bgp: pointer to bandgap instance
577 * @id: sensor id
578 *
579 * Return: data stored by set function with sensor id on success or NULL
580 */
581void *ti_bandgap_get_sensor_data(struct ti_bandgap *bgp, int id)
582{
583 int ret = ti_bandgap_validate(bgp, id);
584 if (ret)
585 return ERR_PTR(error: ret);
586
587 return bgp->regval[id].data;
588}
589
590/*** Helper functions used during device initialization ***/
591
592/**
593 * ti_bandgap_force_single_read() - executes 1 single ADC conversion
594 * @bgp: pointer to struct ti_bandgap
595 * @id: sensor id which it is desired to read 1 temperature
596 *
597 * Used to initialize the conversion state machine and set it to a valid
598 * state. Called during device initialization and context restore events.
599 *
600 * Return: 0
601 */
602static int
603ti_bandgap_force_single_read(struct ti_bandgap *bgp, int id)
604{
605 struct temp_sensor_registers *tsr = bgp->conf->sensors[id].registers;
606 void __iomem *temp_sensor_ctrl = bgp->base + tsr->temp_sensor_ctrl;
607 int error;
608 u32 val;
609
610 /* Select continuous or single conversion mode */
611 if (TI_BANDGAP_HAS(bgp, MODE_CONFIG)) {
612 if (TI_BANDGAP_HAS(bgp, CONT_MODE_ONLY))
613 RMW_BITS(bgp, id, bgap_mode_ctrl, mode_ctrl_mask, 1);
614 else
615 RMW_BITS(bgp, id, bgap_mode_ctrl, mode_ctrl_mask, 0);
616 }
617
618 /* Set Start of Conversion if available */
619 if (tsr->bgap_soc_mask) {
620 RMW_BITS(bgp, id, temp_sensor_ctrl, bgap_soc_mask, 1);
621
622 /* Wait for EOCZ going up */
623 error = readl_poll_timeout_atomic(temp_sensor_ctrl, val,
624 val & tsr->bgap_eocz_mask,
625 1, 1000);
626 if (error)
627 dev_warn(bgp->dev, "eocz timed out waiting high\n");
628
629 /* Clear Start of Conversion if available */
630 RMW_BITS(bgp, id, temp_sensor_ctrl, bgap_soc_mask, 0);
631 }
632
633 /* Wait for EOCZ going down, always needed even if no bgap_soc_mask */
634 error = readl_poll_timeout_atomic(temp_sensor_ctrl, val,
635 !(val & tsr->bgap_eocz_mask),
636 1, 1500);
637 if (error)
638 dev_warn(bgp->dev, "eocz timed out waiting low\n");
639
640 return 0;
641}
642
643/**
644 * ti_bandgap_set_continuous_mode() - One time enabling of continuous mode
645 * @bgp: pointer to struct ti_bandgap
646 *
647 * Call this function only if HAS(MODE_CONFIG) is set. As this driver may
648 * be used for junction temperature monitoring, it is desirable that the
649 * sensors are operational all the time, so that alerts are generated
650 * properly.
651 *
652 * Return: 0
653 */
654static int ti_bandgap_set_continuous_mode(struct ti_bandgap *bgp)
655{
656 int i;
657
658 for (i = 0; i < bgp->conf->sensor_count; i++) {
659 /* Perform a single read just before enabling continuous */
660 ti_bandgap_force_single_read(bgp, id: i);
661 RMW_BITS(bgp, i, bgap_mode_ctrl, mode_ctrl_mask, 1);
662 }
663
664 return 0;
665}
666
667/**
668 * ti_bandgap_get_trend() - To fetch the temperature trend of a sensor
669 * @bgp: pointer to struct ti_bandgap
670 * @id: id of the individual sensor
671 * @trend: Pointer to trend.
672 *
673 * This function needs to be called to fetch the temperature trend of a
674 * Particular sensor. The function computes the difference in temperature
675 * w.r.t time. For the bandgaps with built in history buffer the temperatures
676 * are read from the buffer and for those without the Buffer -ENOTSUPP is
677 * returned.
678 *
679 * Return: 0 if no error, else return corresponding error. If no
680 * error then the trend value is passed on to trend parameter
681 */
682int ti_bandgap_get_trend(struct ti_bandgap *bgp, int id, int *trend)
683{
684 struct temp_sensor_registers *tsr;
685 u32 temp1, temp2, reg1, reg2;
686 int t1, t2, interval, ret = 0;
687
688 ret = ti_bandgap_validate(bgp, id);
689 if (ret)
690 goto exit;
691
692 if (!TI_BANDGAP_HAS(bgp, HISTORY_BUFFER) ||
693 !TI_BANDGAP_HAS(bgp, FREEZE_BIT)) {
694 ret = -ENOTSUPP;
695 goto exit;
696 }
697
698 spin_lock(lock: &bgp->lock);
699
700 tsr = bgp->conf->sensors[id].registers;
701
702 /* Freeze and read the last 2 valid readings */
703 RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 1);
704 reg1 = tsr->ctrl_dtemp_1;
705 reg2 = tsr->ctrl_dtemp_2;
706
707 /* read temperature from history buffer */
708 temp1 = ti_bandgap_readl(bgp, reg: reg1);
709 temp1 &= tsr->bgap_dtemp_mask;
710
711 temp2 = ti_bandgap_readl(bgp, reg: reg2);
712 temp2 &= tsr->bgap_dtemp_mask;
713
714 /* Convert from adc values to mCelsius temperature */
715 ret = ti_bandgap_adc_to_mcelsius(bgp, adc_val: temp1, t: &t1);
716 if (ret)
717 goto unfreeze;
718
719 ret = ti_bandgap_adc_to_mcelsius(bgp, adc_val: temp2, t: &t2);
720 if (ret)
721 goto unfreeze;
722
723 /* Fetch the update interval */
724 ret = ti_bandgap_read_update_interval(bgp, id, interval: &interval);
725 if (ret)
726 goto unfreeze;
727
728 /* Set the interval to 1 ms if bandgap counter delay is not set */
729 if (interval == 0)
730 interval = 1;
731
732 *trend = (t1 - t2) / interval;
733
734 dev_dbg(bgp->dev, "The temperatures are t1 = %d and t2 = %d and trend =%d\n",
735 t1, t2, *trend);
736
737unfreeze:
738 RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 0);
739 spin_unlock(lock: &bgp->lock);
740exit:
741 return ret;
742}
743
744/**
745 * ti_bandgap_tshut_init() - setup and initialize tshut handling
746 * @bgp: pointer to struct ti_bandgap
747 * @pdev: pointer to device struct platform_device
748 *
749 * Call this function only in case the bandgap features HAS(TSHUT).
750 * In this case, the driver needs to handle the TSHUT signal as an IRQ.
751 * The IRQ is wired as a GPIO, and for this purpose, it is required
752 * to specify which GPIO line is used. TSHUT IRQ is fired anytime
753 * one of the bandgap sensors violates the TSHUT high/hot threshold.
754 * And in that case, the system must go off.
755 *
756 * Return: 0 if no error, else error status
757 */
758static int ti_bandgap_tshut_init(struct ti_bandgap *bgp,
759 struct platform_device *pdev)
760{
761 int status;
762
763 status = request_irq(irq: gpiod_to_irq(desc: bgp->tshut_gpiod),
764 handler: ti_bandgap_tshut_irq_handler,
765 IRQF_TRIGGER_RISING, name: "tshut", NULL);
766 if (status)
767 dev_err(bgp->dev, "request irq failed for TSHUT");
768
769 return 0;
770}
771
772/**
773 * ti_bandgap_talert_init() - setup and initialize talert handling
774 * @bgp: pointer to struct ti_bandgap
775 * @pdev: pointer to device struct platform_device
776 *
777 * Call this function only in case the bandgap features HAS(TALERT).
778 * In this case, the driver needs to handle the TALERT signals as an IRQs.
779 * TALERT is a normal IRQ and it is fired any time thresholds (hot or cold)
780 * are violated. In these situation, the driver must reprogram the thresholds,
781 * accordingly to specified policy.
782 *
783 * Return: 0 if no error, else return corresponding error.
784 */
785static int ti_bandgap_talert_init(struct ti_bandgap *bgp,
786 struct platform_device *pdev)
787{
788 int ret;
789
790 bgp->irq = platform_get_irq(pdev, 0);
791 if (bgp->irq < 0)
792 return bgp->irq;
793
794 ret = request_threaded_irq(irq: bgp->irq, NULL,
795 thread_fn: ti_bandgap_talert_irq_handler,
796 IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
797 name: "talert", dev: bgp);
798 if (ret) {
799 dev_err(&pdev->dev, "Request threaded irq failed.\n");
800 return ret;
801 }
802
803 return 0;
804}
805
806static const struct of_device_id of_ti_bandgap_match[];
807/**
808 * ti_bandgap_build() - parse DT and setup a struct ti_bandgap
809 * @pdev: pointer to device struct platform_device
810 *
811 * Used to read the device tree properties accordingly to the bandgap
812 * matching version. Based on bandgap version and its capabilities it
813 * will build a struct ti_bandgap out of the required DT entries.
814 *
815 * Return: valid bandgap structure if successful, else returns ERR_PTR
816 * return value must be verified with IS_ERR.
817 */
818static struct ti_bandgap *ti_bandgap_build(struct platform_device *pdev)
819{
820 struct device_node *node = pdev->dev.of_node;
821 const struct of_device_id *of_id;
822 struct ti_bandgap *bgp;
823 struct resource *res;
824 int i;
825
826 /* just for the sake */
827 if (!node) {
828 dev_err(&pdev->dev, "no platform information available\n");
829 return ERR_PTR(error: -EINVAL);
830 }
831
832 bgp = devm_kzalloc(dev: &pdev->dev, size: sizeof(*bgp), GFP_KERNEL);
833 if (!bgp)
834 return ERR_PTR(error: -ENOMEM);
835
836 of_id = of_match_device(matches: of_ti_bandgap_match, dev: &pdev->dev);
837 if (of_id)
838 bgp->conf = of_id->data;
839
840 /* register shadow for context save and restore */
841 bgp->regval = devm_kcalloc(dev: &pdev->dev, n: bgp->conf->sensor_count,
842 size: sizeof(*bgp->regval), GFP_KERNEL);
843 if (!bgp->regval)
844 return ERR_PTR(error: -ENOMEM);
845
846 i = 0;
847 do {
848 void __iomem *chunk;
849
850 res = platform_get_resource(pdev, IORESOURCE_MEM, i);
851 if (!res)
852 break;
853 chunk = devm_ioremap_resource(dev: &pdev->dev, res);
854 if (i == 0)
855 bgp->base = chunk;
856 if (IS_ERR(ptr: chunk))
857 return ERR_CAST(ptr: chunk);
858
859 i++;
860 } while (res);
861
862 if (TI_BANDGAP_HAS(bgp, TSHUT)) {
863 bgp->tshut_gpiod = devm_gpiod_get(dev: &pdev->dev, NULL, flags: GPIOD_IN);
864 if (IS_ERR(ptr: bgp->tshut_gpiod)) {
865 dev_err(&pdev->dev, "invalid gpio for tshut\n");
866 return ERR_CAST(ptr: bgp->tshut_gpiod);
867 }
868 }
869
870 return bgp;
871}
872
873/*
874 * List of SoCs on which the CPU PM notifier can cause erros on the DTEMP
875 * readout.
876 * Enabled notifier on these machines results in erroneous, random values which
877 * could trigger unexpected thermal shutdown.
878 */
879static const struct soc_device_attribute soc_no_cpu_notifier[] = {
880 { .machine = "OMAP4430" },
881 { /* sentinel */ }
882};
883
884/*** Device driver call backs ***/
885
886static
887int ti_bandgap_probe(struct platform_device *pdev)
888{
889 struct ti_bandgap *bgp;
890 int clk_rate, ret, i;
891
892 bgp = ti_bandgap_build(pdev);
893 if (IS_ERR(ptr: bgp)) {
894 dev_err(&pdev->dev, "failed to fetch platform data\n");
895 return PTR_ERR(ptr: bgp);
896 }
897 bgp->dev = &pdev->dev;
898
899 if (TI_BANDGAP_HAS(bgp, UNRELIABLE))
900 dev_warn(&pdev->dev,
901 "This OMAP thermal sensor is unreliable. You've been warned\n");
902
903 if (TI_BANDGAP_HAS(bgp, TSHUT)) {
904 ret = ti_bandgap_tshut_init(bgp, pdev);
905 if (ret) {
906 dev_err(&pdev->dev,
907 "failed to initialize system tshut IRQ\n");
908 return ret;
909 }
910 }
911
912 bgp->fclock = clk_get(NULL, id: bgp->conf->fclock_name);
913 if (IS_ERR(ptr: bgp->fclock)) {
914 dev_err(&pdev->dev, "failed to request fclock reference\n");
915 ret = PTR_ERR(ptr: bgp->fclock);
916 goto free_irqs;
917 }
918
919 bgp->div_clk = clk_get(NULL, id: bgp->conf->div_ck_name);
920 if (IS_ERR(ptr: bgp->div_clk)) {
921 dev_err(&pdev->dev, "failed to request div_ts_ck clock ref\n");
922 ret = PTR_ERR(ptr: bgp->div_clk);
923 goto put_fclock;
924 }
925
926 for (i = 0; i < bgp->conf->sensor_count; i++) {
927 struct temp_sensor_registers *tsr;
928 u32 val;
929
930 tsr = bgp->conf->sensors[i].registers;
931 /*
932 * check if the efuse has a non-zero value if not
933 * it is an untrimmed sample and the temperatures
934 * may not be accurate
935 */
936 val = ti_bandgap_readl(bgp, reg: tsr->bgap_efuse);
937 if (!val)
938 dev_info(&pdev->dev,
939 "Non-trimmed BGAP, Temp not accurate\n");
940 }
941
942 clk_rate = clk_round_rate(clk: bgp->div_clk,
943 rate: bgp->conf->sensors[0].ts_data->max_freq);
944 if (clk_rate < bgp->conf->sensors[0].ts_data->min_freq ||
945 clk_rate <= 0) {
946 ret = -ENODEV;
947 dev_err(&pdev->dev, "wrong clock rate (%d)\n", clk_rate);
948 goto put_clks;
949 }
950
951 ret = clk_set_rate(clk: bgp->div_clk, rate: clk_rate);
952 if (ret)
953 dev_err(&pdev->dev, "Cannot re-set clock rate. Continuing\n");
954
955 bgp->clk_rate = clk_rate;
956 if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
957 clk_prepare_enable(clk: bgp->fclock);
958
959
960 spin_lock_init(&bgp->lock);
961 bgp->dev = &pdev->dev;
962 platform_set_drvdata(pdev, data: bgp);
963
964 ti_bandgap_power(bgp, on: true);
965
966 /* Set default counter to 1 for now */
967 if (TI_BANDGAP_HAS(bgp, COUNTER))
968 for (i = 0; i < bgp->conf->sensor_count; i++)
969 RMW_BITS(bgp, i, bgap_counter, counter_mask, 1);
970
971 /* Set default thresholds for alert and shutdown */
972 for (i = 0; i < bgp->conf->sensor_count; i++) {
973 struct temp_sensor_data *ts_data;
974
975 ts_data = bgp->conf->sensors[i].ts_data;
976
977 if (TI_BANDGAP_HAS(bgp, TALERT)) {
978 /* Set initial Talert thresholds */
979 RMW_BITS(bgp, i, bgap_threshold,
980 threshold_tcold_mask, ts_data->t_cold);
981 RMW_BITS(bgp, i, bgap_threshold,
982 threshold_thot_mask, ts_data->t_hot);
983 /* Enable the alert events */
984 RMW_BITS(bgp, i, bgap_mask_ctrl, mask_hot_mask, 1);
985 RMW_BITS(bgp, i, bgap_mask_ctrl, mask_cold_mask, 1);
986 }
987
988 if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG)) {
989 /* Set initial Tshut thresholds */
990 RMW_BITS(bgp, i, tshut_threshold,
991 tshut_hot_mask, ts_data->tshut_hot);
992 RMW_BITS(bgp, i, tshut_threshold,
993 tshut_cold_mask, ts_data->tshut_cold);
994 }
995 }
996
997 if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
998 ti_bandgap_set_continuous_mode(bgp);
999
1000 /* Set .250 seconds time as default counter */
1001 if (TI_BANDGAP_HAS(bgp, COUNTER))
1002 for (i = 0; i < bgp->conf->sensor_count; i++)
1003 RMW_BITS(bgp, i, bgap_counter, counter_mask,
1004 bgp->clk_rate / 4);
1005
1006 /* Every thing is good? Then expose the sensors */
1007 for (i = 0; i < bgp->conf->sensor_count; i++) {
1008 char *domain;
1009
1010 if (bgp->conf->sensors[i].register_cooling) {
1011 ret = bgp->conf->sensors[i].register_cooling(bgp, i);
1012 if (ret)
1013 goto remove_sensors;
1014 }
1015
1016 if (bgp->conf->expose_sensor) {
1017 domain = bgp->conf->sensors[i].domain;
1018 ret = bgp->conf->expose_sensor(bgp, i, domain);
1019 if (ret)
1020 goto remove_last_cooling;
1021 }
1022 }
1023
1024 /*
1025 * Enable the Interrupts once everything is set. Otherwise irq handler
1026 * might be called as soon as it is enabled where as rest of framework
1027 * is still getting initialised.
1028 */
1029 if (TI_BANDGAP_HAS(bgp, TALERT)) {
1030 ret = ti_bandgap_talert_init(bgp, pdev);
1031 if (ret) {
1032 dev_err(&pdev->dev, "failed to initialize Talert IRQ\n");
1033 i = bgp->conf->sensor_count;
1034 goto disable_clk;
1035 }
1036 }
1037
1038#ifdef CONFIG_PM_SLEEP
1039 bgp->nb.notifier_call = bandgap_omap_cpu_notifier;
1040 if (!soc_device_match(matches: soc_no_cpu_notifier))
1041 cpu_pm_register_notifier(nb: &bgp->nb);
1042#endif
1043
1044 return 0;
1045
1046remove_last_cooling:
1047 if (bgp->conf->sensors[i].unregister_cooling)
1048 bgp->conf->sensors[i].unregister_cooling(bgp, i);
1049remove_sensors:
1050 for (i--; i >= 0; i--) {
1051 if (bgp->conf->sensors[i].unregister_cooling)
1052 bgp->conf->sensors[i].unregister_cooling(bgp, i);
1053 if (bgp->conf->remove_sensor)
1054 bgp->conf->remove_sensor(bgp, i);
1055 }
1056 ti_bandgap_power(bgp, on: false);
1057disable_clk:
1058 if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1059 clk_disable_unprepare(clk: bgp->fclock);
1060put_clks:
1061 clk_put(clk: bgp->div_clk);
1062put_fclock:
1063 clk_put(clk: bgp->fclock);
1064free_irqs:
1065 if (TI_BANDGAP_HAS(bgp, TSHUT))
1066 free_irq(gpiod_to_irq(desc: bgp->tshut_gpiod), NULL);
1067
1068 return ret;
1069}
1070
1071static
1072void ti_bandgap_remove(struct platform_device *pdev)
1073{
1074 struct ti_bandgap *bgp = platform_get_drvdata(pdev);
1075 int i;
1076
1077 if (!soc_device_match(matches: soc_no_cpu_notifier))
1078 cpu_pm_unregister_notifier(nb: &bgp->nb);
1079
1080 /* Remove sensor interfaces */
1081 for (i = 0; i < bgp->conf->sensor_count; i++) {
1082 if (bgp->conf->sensors[i].unregister_cooling)
1083 bgp->conf->sensors[i].unregister_cooling(bgp, i);
1084
1085 if (bgp->conf->remove_sensor)
1086 bgp->conf->remove_sensor(bgp, i);
1087 }
1088
1089 ti_bandgap_power(bgp, on: false);
1090
1091 if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1092 clk_disable_unprepare(clk: bgp->fclock);
1093 clk_put(clk: bgp->fclock);
1094 clk_put(clk: bgp->div_clk);
1095
1096 if (TI_BANDGAP_HAS(bgp, TALERT))
1097 free_irq(bgp->irq, bgp);
1098
1099 if (TI_BANDGAP_HAS(bgp, TSHUT))
1100 free_irq(gpiod_to_irq(desc: bgp->tshut_gpiod), NULL);
1101}
1102
1103#ifdef CONFIG_PM_SLEEP
1104static int ti_bandgap_save_ctxt(struct ti_bandgap *bgp)
1105{
1106 int i;
1107
1108 for (i = 0; i < bgp->conf->sensor_count; i++) {
1109 struct temp_sensor_registers *tsr;
1110 struct temp_sensor_regval *rval;
1111
1112 rval = &bgp->regval[i];
1113 tsr = bgp->conf->sensors[i].registers;
1114
1115 if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
1116 rval->bg_mode_ctrl = ti_bandgap_readl(bgp,
1117 reg: tsr->bgap_mode_ctrl);
1118 if (TI_BANDGAP_HAS(bgp, COUNTER))
1119 rval->bg_counter = ti_bandgap_readl(bgp,
1120 reg: tsr->bgap_counter);
1121 if (TI_BANDGAP_HAS(bgp, TALERT)) {
1122 rval->bg_threshold = ti_bandgap_readl(bgp,
1123 reg: tsr->bgap_threshold);
1124 rval->bg_ctrl = ti_bandgap_readl(bgp,
1125 reg: tsr->bgap_mask_ctrl);
1126 }
1127
1128 if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG))
1129 rval->tshut_threshold = ti_bandgap_readl(bgp,
1130 reg: tsr->tshut_threshold);
1131 }
1132
1133 return 0;
1134}
1135
1136static int ti_bandgap_restore_ctxt(struct ti_bandgap *bgp)
1137{
1138 int i;
1139
1140 for (i = 0; i < bgp->conf->sensor_count; i++) {
1141 struct temp_sensor_registers *tsr;
1142 struct temp_sensor_regval *rval;
1143
1144 rval = &bgp->regval[i];
1145 tsr = bgp->conf->sensors[i].registers;
1146
1147 if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG))
1148 ti_bandgap_writel(bgp, val: rval->tshut_threshold,
1149 reg: tsr->tshut_threshold);
1150 /* Force immediate temperature measurement and update
1151 * of the DTEMP field
1152 */
1153 ti_bandgap_force_single_read(bgp, id: i);
1154
1155 if (TI_BANDGAP_HAS(bgp, COUNTER))
1156 ti_bandgap_writel(bgp, val: rval->bg_counter,
1157 reg: tsr->bgap_counter);
1158 if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
1159 ti_bandgap_writel(bgp, val: rval->bg_mode_ctrl,
1160 reg: tsr->bgap_mode_ctrl);
1161 if (TI_BANDGAP_HAS(bgp, TALERT)) {
1162 ti_bandgap_writel(bgp, val: rval->bg_threshold,
1163 reg: tsr->bgap_threshold);
1164 ti_bandgap_writel(bgp, val: rval->bg_ctrl,
1165 reg: tsr->bgap_mask_ctrl);
1166 }
1167 }
1168
1169 return 0;
1170}
1171
1172static int ti_bandgap_suspend(struct device *dev)
1173{
1174 struct ti_bandgap *bgp = dev_get_drvdata(dev);
1175 int err;
1176
1177 err = ti_bandgap_save_ctxt(bgp);
1178 ti_bandgap_power(bgp, on: false);
1179
1180 if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1181 clk_disable_unprepare(clk: bgp->fclock);
1182
1183 bgp->is_suspended = true;
1184
1185 return err;
1186}
1187
1188static int bandgap_omap_cpu_notifier(struct notifier_block *nb,
1189 unsigned long cmd, void *v)
1190{
1191 struct ti_bandgap *bgp;
1192
1193 bgp = container_of(nb, struct ti_bandgap, nb);
1194
1195 spin_lock(lock: &bgp->lock);
1196 switch (cmd) {
1197 case CPU_CLUSTER_PM_ENTER:
1198 if (bgp->is_suspended)
1199 break;
1200 ti_bandgap_save_ctxt(bgp);
1201 ti_bandgap_power(bgp, on: false);
1202 if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1203 clk_disable(clk: bgp->fclock);
1204 break;
1205 case CPU_CLUSTER_PM_ENTER_FAILED:
1206 case CPU_CLUSTER_PM_EXIT:
1207 if (bgp->is_suspended)
1208 break;
1209 if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1210 clk_enable(clk: bgp->fclock);
1211 ti_bandgap_power(bgp, on: true);
1212 ti_bandgap_restore_ctxt(bgp);
1213 break;
1214 }
1215 spin_unlock(lock: &bgp->lock);
1216
1217 return NOTIFY_OK;
1218}
1219
1220static int ti_bandgap_resume(struct device *dev)
1221{
1222 struct ti_bandgap *bgp = dev_get_drvdata(dev);
1223
1224 if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1225 clk_prepare_enable(clk: bgp->fclock);
1226
1227 ti_bandgap_power(bgp, on: true);
1228 bgp->is_suspended = false;
1229
1230 return ti_bandgap_restore_ctxt(bgp);
1231}
1232static SIMPLE_DEV_PM_OPS(ti_bandgap_dev_pm_ops, ti_bandgap_suspend,
1233 ti_bandgap_resume);
1234
1235#define DEV_PM_OPS (&ti_bandgap_dev_pm_ops)
1236#else
1237#define DEV_PM_OPS NULL
1238#endif
1239
1240static const struct of_device_id of_ti_bandgap_match[] = {
1241#ifdef CONFIG_OMAP3_THERMAL
1242 {
1243 .compatible = "ti,omap34xx-bandgap",
1244 .data = (void *)&omap34xx_data,
1245 },
1246 {
1247 .compatible = "ti,omap36xx-bandgap",
1248 .data = (void *)&omap36xx_data,
1249 },
1250#endif
1251#ifdef CONFIG_OMAP4_THERMAL
1252 {
1253 .compatible = "ti,omap4430-bandgap",
1254 .data = (void *)&omap4430_data,
1255 },
1256 {
1257 .compatible = "ti,omap4460-bandgap",
1258 .data = (void *)&omap4460_data,
1259 },
1260 {
1261 .compatible = "ti,omap4470-bandgap",
1262 .data = (void *)&omap4470_data,
1263 },
1264#endif
1265#ifdef CONFIG_OMAP5_THERMAL
1266 {
1267 .compatible = "ti,omap5430-bandgap",
1268 .data = (void *)&omap5430_data,
1269 },
1270#endif
1271#ifdef CONFIG_DRA752_THERMAL
1272 {
1273 .compatible = "ti,dra752-bandgap",
1274 .data = (void *)&dra752_data,
1275 },
1276#endif
1277 /* Sentinel */
1278 { },
1279};
1280MODULE_DEVICE_TABLE(of, of_ti_bandgap_match);
1281
1282static struct platform_driver ti_bandgap_sensor_driver = {
1283 .probe = ti_bandgap_probe,
1284 .remove_new = ti_bandgap_remove,
1285 .driver = {
1286 .name = "ti-soc-thermal",
1287 .pm = DEV_PM_OPS,
1288 .of_match_table = of_ti_bandgap_match,
1289 },
1290};
1291
1292module_platform_driver(ti_bandgap_sensor_driver);
1293
1294MODULE_DESCRIPTION("OMAP4+ bandgap temperature sensor driver");
1295MODULE_LICENSE("GPL v2");
1296MODULE_ALIAS("platform:ti-soc-thermal");
1297MODULE_AUTHOR("Texas Instrument Inc.");
1298

source code of linux/drivers/thermal/ti-soc-thermal/ti-bandgap.c