2 * TI Bandgap temperature sensor driver
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>
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.
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.
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
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>
44 #include "ti-bandgap.h"
46 /*** Helper functions to access registers and their bitfields ***/
49 * ti_bandgap_readl() - simple read helper function
50 * @bgp: pointer to ti_bandgap structure
51 * @reg: desired register (offset) to be read
53 * Helper function to read bandgap registers. It uses the io remapped area.
54 * Return: the register value.
56 static u32 ti_bandgap_readl(struct ti_bandgap *bgp, u32 reg)
58 return readl(bgp->base + reg);
62 * ti_bandgap_writel() - simple write helper function
63 * @bgp: pointer to ti_bandgap structure
64 * @val: desired register value to be written
65 * @reg: desired register (offset) to be written
67 * Helper function to write bandgap registers. It uses the io remapped area.
69 static void ti_bandgap_writel(struct ti_bandgap *bgp, u32 val, u32 reg)
71 writel(val, bgp->base + reg);
75 * DOC: macro to update bits.
77 * RMW_BITS() - used to read, modify and update bandgap bitfields.
78 * The value passed will be shifted.
80 #define RMW_BITS(bgp, id, reg, mask, val) \
82 struct temp_sensor_registers *t; \
85 t = bgp->conf->sensors[(id)].registers; \
86 r = ti_bandgap_readl(bgp, t->reg); \
88 r |= (val) << __ffs(t->mask); \
89 ti_bandgap_writel(bgp, r, t->reg); \
92 /*** Basic helper functions ***/
95 * ti_bandgap_power() - controls the power state of a bandgap device
96 * @bgp: pointer to ti_bandgap structure
97 * @on: desired power state (1 - on, 0 - off)
99 * Used to power on/off a bandgap device instance. Only used on those
100 * that features tempsoff bit.
102 * Return: 0 on success, -ENOTSUPP if tempsoff is not supported.
104 static int ti_bandgap_power(struct ti_bandgap *bgp, bool on)
108 if (!TI_BANDGAP_HAS(bgp, POWER_SWITCH)) {
113 for (i = 0; i < bgp->conf->sensor_count; i++)
115 RMW_BITS(bgp, i, temp_sensor_ctrl, bgap_tempsoff_mask, !on);
122 * ti_bandgap_read_temp() - helper function to read sensor temperature
123 * @bgp: pointer to ti_bandgap structure
124 * @id: bandgap sensor id
126 * Function to concentrate the steps to read sensor temperature register.
127 * This function is desired because, depending on bandgap device version,
128 * it might be needed to freeze the bandgap state machine, before fetching
129 * the register value.
131 * Return: temperature in ADC values.
133 static u32 ti_bandgap_read_temp(struct ti_bandgap *bgp, int id)
135 struct temp_sensor_registers *tsr;
138 tsr = bgp->conf->sensors[id].registers;
139 reg = tsr->temp_sensor_ctrl;
141 if (TI_BANDGAP_HAS(bgp, FREEZE_BIT)) {
142 RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 1);
144 * In case we cannot read from cur_dtemp / dtemp_0,
145 * then we read from the last valid temp read
147 reg = tsr->ctrl_dtemp_1;
150 /* read temperature */
151 temp = ti_bandgap_readl(bgp, reg);
152 temp &= tsr->bgap_dtemp_mask;
154 if (TI_BANDGAP_HAS(bgp, FREEZE_BIT))
155 RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 0);
160 /*** IRQ handlers ***/
163 * ti_bandgap_talert_irq_handler() - handles Temperature alert IRQs
165 * @data: private data (struct ti_bandgap *)
167 * This is the Talert handler. Use it only if bandgap device features
168 * HAS(TALERT). This handler goes over all sensors and checks their
169 * conditions and acts accordingly. In case there are events pending,
170 * it will reset the event mask to wait for the opposite event (next event).
171 * Every time there is a new event, it will be reported to thermal layer.
173 * Return: IRQ_HANDLED
175 static irqreturn_t ti_bandgap_talert_irq_handler(int irq, void *data)
177 struct ti_bandgap *bgp = data;
178 struct temp_sensor_registers *tsr;
179 u32 t_hot = 0, t_cold = 0, ctrl;
182 spin_lock(&bgp->lock);
183 for (i = 0; i < bgp->conf->sensor_count; i++) {
184 tsr = bgp->conf->sensors[i].registers;
185 ctrl = ti_bandgap_readl(bgp, tsr->bgap_status);
187 /* Read the status of t_hot */
188 t_hot = ctrl & tsr->status_hot_mask;
190 /* Read the status of t_cold */
191 t_cold = ctrl & tsr->status_cold_mask;
193 if (!t_cold && !t_hot)
196 ctrl = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
198 * One TALERT interrupt: Two sources
199 * If the interrupt is due to t_hot then mask t_hot and
200 * and unmask t_cold else mask t_cold and unmask t_hot
203 ctrl &= ~tsr->mask_hot_mask;
204 ctrl |= tsr->mask_cold_mask;
206 ctrl &= ~tsr->mask_cold_mask;
207 ctrl |= tsr->mask_hot_mask;
210 ti_bandgap_writel(bgp, ctrl, tsr->bgap_mask_ctrl);
213 "%s: IRQ from %s sensor: hotevent %d coldevent %d\n",
214 __func__, bgp->conf->sensors[i].domain,
217 /* report temperature to whom may concern */
218 if (bgp->conf->report_temperature)
219 bgp->conf->report_temperature(bgp, i);
221 spin_unlock(&bgp->lock);
227 * ti_bandgap_tshut_irq_handler() - handles Temperature shutdown signal
229 * @data: private data (unused)
231 * This is the Tshut handler. Use it only if bandgap device features
232 * HAS(TSHUT). If any sensor fires the Tshut signal, we simply shutdown
235 * Return: IRQ_HANDLED
237 static irqreturn_t ti_bandgap_tshut_irq_handler(int irq, void *data)
239 pr_emerg("%s: TSHUT temperature reached. Needs shut down...\n",
242 orderly_poweroff(true);
247 /*** Helper functions which manipulate conversion ADC <-> mi Celsius ***/
250 * ti_bandgap_adc_to_mcelsius() - converts an ADC value to mCelsius scale
251 * @bgp: struct ti_bandgap pointer
252 * @adc_val: value in ADC representation
253 * @t: address where to write the resulting temperature in mCelsius
255 * Simple conversion from ADC representation to mCelsius. In case the ADC value
256 * is out of the ADC conv table range, it returns -ERANGE, 0 on success.
257 * The conversion table is indexed by the ADC values.
259 * Return: 0 if conversion was successful, else -ERANGE in case the @adc_val
260 * argument is out of the ADC conv table range.
263 int ti_bandgap_adc_to_mcelsius(struct ti_bandgap *bgp, int adc_val, int *t)
265 const struct ti_bandgap_data *conf = bgp->conf;
268 /* look up for temperature in the table and return the temperature */
269 if (adc_val < conf->adc_start_val || adc_val > conf->adc_end_val) {
274 *t = bgp->conf->conv_table[adc_val - conf->adc_start_val];
281 * ti_bandgap_mcelsius_to_adc() - converts a mCelsius value to ADC scale
282 * @bgp: struct ti_bandgap pointer
283 * @temp: value in mCelsius
284 * @adc: address where to write the resulting temperature in ADC representation
286 * Simple conversion from mCelsius to ADC values. In case the temp value
287 * is out of the ADC conv table range, it returns -ERANGE, 0 on success.
288 * The conversion table is indexed by the ADC values.
290 * Return: 0 if conversion was successful, else -ERANGE in case the @temp
291 * argument is out of the ADC conv table range.
294 int ti_bandgap_mcelsius_to_adc(struct ti_bandgap *bgp, long temp, int *adc)
296 const struct ti_bandgap_data *conf = bgp->conf;
297 const int *conv_table = bgp->conf->conv_table;
298 int high, low, mid, ret = 0;
301 high = conf->adc_end_val - conf->adc_start_val;
302 mid = (high + low) / 2;
304 if (temp < conv_table[low] || temp > conv_table[high]) {
310 if (temp < conv_table[mid])
314 mid = (low + high) / 2;
317 *adc = conf->adc_start_val + low;
324 * ti_bandgap_add_hyst() - add hysteresis (in mCelsius) to an ADC value
325 * @bgp: struct ti_bandgap pointer
326 * @adc_val: temperature value in ADC representation
327 * @hyst_val: hysteresis value in mCelsius
328 * @sum: address where to write the resulting temperature (in ADC scale)
330 * Adds an hysteresis value (in mCelsius) to a ADC temperature value.
332 * Return: 0 on success, -ERANGE otherwise.
335 int ti_bandgap_add_hyst(struct ti_bandgap *bgp, int adc_val, int hyst_val,
341 * Need to add in the mcelsius domain, so we have a temperature
342 * the conv_table range
344 ret = ti_bandgap_adc_to_mcelsius(bgp, adc_val, &temp);
350 ret = ti_bandgap_mcelsius_to_adc(bgp, temp, sum);
356 /*** Helper functions handling device Alert/Shutdown signals ***/
359 * ti_bandgap_unmask_interrupts() - unmasks the events of thot & tcold
360 * @bgp: struct ti_bandgap pointer
361 * @id: bandgap sensor id
362 * @t_hot: hot temperature value to trigger alert signal
363 * @t_cold: cold temperature value to trigger alert signal
365 * Checks the requested t_hot and t_cold values and configures the IRQ event
366 * masks accordingly. Call this function only if bandgap features HAS(TALERT).
368 static void ti_bandgap_unmask_interrupts(struct ti_bandgap *bgp, int id,
369 u32 t_hot, u32 t_cold)
371 struct temp_sensor_registers *tsr;
374 /* Read the current on die temperature */
375 temp = ti_bandgap_read_temp(bgp, id);
377 tsr = bgp->conf->sensors[id].registers;
378 reg_val = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
381 reg_val |= tsr->mask_hot_mask;
383 reg_val &= ~tsr->mask_hot_mask;
386 reg_val |= tsr->mask_cold_mask;
388 reg_val &= ~tsr->mask_cold_mask;
389 ti_bandgap_writel(bgp, reg_val, tsr->bgap_mask_ctrl);
393 * ti_bandgap_update_alert_threshold() - sequence to update thresholds
394 * @bgp: struct ti_bandgap pointer
395 * @id: bandgap sensor id
396 * @val: value (ADC) of a new threshold
397 * @hot: desired threshold to be updated. true if threshold hot, false if
400 * It will program the required thresholds (hot and cold) for TALERT signal.
401 * This function can be used to update t_hot or t_cold, depending on @hot value.
402 * It checks the resulting t_hot and t_cold values, based on the new passed @val
403 * and configures the thresholds so that t_hot is always greater than t_cold.
404 * Call this function only if bandgap features HAS(TALERT).
406 * Return: 0 if no error, else corresponding error
408 static int ti_bandgap_update_alert_threshold(struct ti_bandgap *bgp, int id,
411 struct temp_sensor_data *ts_data = bgp->conf->sensors[id].ts_data;
412 struct temp_sensor_registers *tsr;
413 u32 thresh_val, reg_val, t_hot, t_cold;
416 tsr = bgp->conf->sensors[id].registers;
418 /* obtain the current value */
419 thresh_val = ti_bandgap_readl(bgp, tsr->bgap_threshold);
420 t_cold = (thresh_val & tsr->threshold_tcold_mask) >>
421 __ffs(tsr->threshold_tcold_mask);
422 t_hot = (thresh_val & tsr->threshold_thot_mask) >>
423 __ffs(tsr->threshold_thot_mask);
429 if (t_cold > t_hot) {
431 err = ti_bandgap_add_hyst(bgp, t_hot,
435 err = ti_bandgap_add_hyst(bgp, t_cold,
440 /* write the new threshold values */
441 reg_val = thresh_val &
442 ~(tsr->threshold_thot_mask | tsr->threshold_tcold_mask);
443 reg_val |= (t_hot << __ffs(tsr->threshold_thot_mask)) |
444 (t_cold << __ffs(tsr->threshold_tcold_mask));
445 ti_bandgap_writel(bgp, reg_val, tsr->bgap_threshold);
448 dev_err(bgp->dev, "failed to reprogram thot threshold\n");
453 ti_bandgap_unmask_interrupts(bgp, id, t_hot, t_cold);
459 * ti_bandgap_validate() - helper to check the sanity of a struct ti_bandgap
460 * @bgp: struct ti_bandgap pointer
461 * @id: bandgap sensor id
463 * Checks if the bandgap pointer is valid and if the sensor id is also
466 * Return: 0 if no errors, -EINVAL for invalid @bgp pointer or -ERANGE if
467 * @id cannot index @bgp sensors.
469 static inline int ti_bandgap_validate(struct ti_bandgap *bgp, int id)
473 if (!bgp || IS_ERR(bgp)) {
474 pr_err("%s: invalid bandgap pointer\n", __func__);
479 if ((id < 0) || (id >= bgp->conf->sensor_count)) {
480 dev_err(bgp->dev, "%s: sensor id out of range (%d)\n",
490 * _ti_bandgap_write_threshold() - helper to update TALERT t_cold or t_hot
491 * @bgp: struct ti_bandgap pointer
492 * @id: bandgap sensor id
493 * @val: value (mCelsius) of a new threshold
494 * @hot: desired threshold to be updated. true if threshold hot, false if
497 * It will update the required thresholds (hot and cold) for TALERT signal.
498 * This function can be used to update t_hot or t_cold, depending on @hot value.
499 * Validates the mCelsius range and update the requested threshold.
500 * Call this function only if bandgap features HAS(TALERT).
502 * Return: 0 if no error, else corresponding error value.
504 static int _ti_bandgap_write_threshold(struct ti_bandgap *bgp, int id, int val,
507 struct temp_sensor_data *ts_data;
508 struct temp_sensor_registers *tsr;
512 ret = ti_bandgap_validate(bgp, id);
516 if (!TI_BANDGAP_HAS(bgp, TALERT)) {
521 ts_data = bgp->conf->sensors[id].ts_data;
522 tsr = bgp->conf->sensors[id].registers;
524 if (val < ts_data->min_temp + ts_data->hyst_val)
527 if (val > ts_data->max_temp + ts_data->hyst_val)
534 ret = ti_bandgap_mcelsius_to_adc(bgp, val, &adc_val);
538 spin_lock(&bgp->lock);
539 ret = ti_bandgap_update_alert_threshold(bgp, id, adc_val, hot);
540 spin_unlock(&bgp->lock);
547 * _ti_bandgap_read_threshold() - helper to read TALERT t_cold or t_hot
548 * @bgp: struct ti_bandgap pointer
549 * @id: bandgap sensor id
550 * @val: value (mCelsius) of a threshold
551 * @hot: desired threshold to be read. true if threshold hot, false if
554 * It will fetch the required thresholds (hot and cold) for TALERT signal.
555 * This function can be used to read t_hot or t_cold, depending on @hot value.
556 * Call this function only if bandgap features HAS(TALERT).
558 * Return: 0 if no error, -ENOTSUPP if it has no TALERT support, or the
559 * corresponding error value if some operation fails.
561 static int _ti_bandgap_read_threshold(struct ti_bandgap *bgp, int id,
564 struct temp_sensor_registers *tsr;
568 ret = ti_bandgap_validate(bgp, id);
572 if (!TI_BANDGAP_HAS(bgp, TALERT)) {
577 tsr = bgp->conf->sensors[id].registers;
579 mask = tsr->threshold_thot_mask;
581 mask = tsr->threshold_tcold_mask;
583 temp = ti_bandgap_readl(bgp, tsr->bgap_threshold);
584 temp = (temp & mask) >> __ffs(mask);
585 ret |= ti_bandgap_adc_to_mcelsius(bgp, temp, &temp);
587 dev_err(bgp->dev, "failed to read thot\n");
598 /*** Exposed APIs ***/
601 * ti_bandgap_read_thot() - reads sensor current thot
602 * @bgp: pointer to bandgap instance
604 * @thot: resulting current thot value
606 * Return: 0 on success or the proper error code
608 int ti_bandgap_read_thot(struct ti_bandgap *bgp, int id, int *thot)
610 return _ti_bandgap_read_threshold(bgp, id, thot, true);
614 * ti_bandgap_write_thot() - sets sensor current thot
615 * @bgp: pointer to bandgap instance
617 * @val: desired thot value
619 * Return: 0 on success or the proper error code
621 int ti_bandgap_write_thot(struct ti_bandgap *bgp, int id, int val)
623 return _ti_bandgap_write_threshold(bgp, id, val, true);
627 * ti_bandgap_read_tcold() - reads sensor current tcold
628 * @bgp: pointer to bandgap instance
630 * @tcold: resulting current tcold value
632 * Return: 0 on success or the proper error code
634 int ti_bandgap_read_tcold(struct ti_bandgap *bgp, int id, int *tcold)
636 return _ti_bandgap_read_threshold(bgp, id, tcold, false);
640 * ti_bandgap_write_tcold() - sets the sensor tcold
641 * @bgp: pointer to bandgap instance
643 * @val: desired tcold value
645 * Return: 0 on success or the proper error code
647 int ti_bandgap_write_tcold(struct ti_bandgap *bgp, int id, int val)
649 return _ti_bandgap_write_threshold(bgp, id, val, false);
653 * ti_bandgap_read_counter() - read the sensor counter
654 * @bgp: pointer to bandgap instance
656 * @interval: resulting update interval in miliseconds
658 static void ti_bandgap_read_counter(struct ti_bandgap *bgp, int id,
661 struct temp_sensor_registers *tsr;
664 tsr = bgp->conf->sensors[id].registers;
665 time = ti_bandgap_readl(bgp, tsr->bgap_counter);
666 time = (time & tsr->counter_mask) >>
667 __ffs(tsr->counter_mask);
668 time = time * 1000 / bgp->clk_rate;
673 * ti_bandgap_read_counter_delay() - read the sensor counter delay
674 * @bgp: pointer to bandgap instance
676 * @interval: resulting update interval in miliseconds
678 static void ti_bandgap_read_counter_delay(struct ti_bandgap *bgp, int id,
681 struct temp_sensor_registers *tsr;
684 tsr = bgp->conf->sensors[id].registers;
686 reg_val = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
687 reg_val = (reg_val & tsr->mask_counter_delay_mask) >>
688 __ffs(tsr->mask_counter_delay_mask);
709 dev_warn(bgp->dev, "Wrong counter delay value read from register %X",
715 * ti_bandgap_read_update_interval() - read the sensor update interval
716 * @bgp: pointer to bandgap instance
718 * @interval: resulting update interval in miliseconds
720 * Return: 0 on success or the proper error code
722 int ti_bandgap_read_update_interval(struct ti_bandgap *bgp, int id,
727 ret = ti_bandgap_validate(bgp, id);
731 if (!TI_BANDGAP_HAS(bgp, COUNTER) &&
732 !TI_BANDGAP_HAS(bgp, COUNTER_DELAY)) {
737 if (TI_BANDGAP_HAS(bgp, COUNTER)) {
738 ti_bandgap_read_counter(bgp, id, interval);
742 ti_bandgap_read_counter_delay(bgp, id, interval);
748 * ti_bandgap_write_counter_delay() - set the counter_delay
749 * @bgp: pointer to bandgap instance
751 * @interval: desired update interval in miliseconds
753 * Return: 0 on success or the proper error code
755 static int ti_bandgap_write_counter_delay(struct ti_bandgap *bgp, int id,
761 case 0: /* Immediate conversion */
764 case 1: /* Conversion after ever 1ms */
767 case 10: /* Conversion after ever 10ms */
770 case 100: /* Conversion after ever 100ms */
773 case 250: /* Conversion after ever 250ms */
776 case 500: /* Conversion after ever 500ms */
780 dev_warn(bgp->dev, "Delay %d ms is not supported\n", interval);
784 spin_lock(&bgp->lock);
785 RMW_BITS(bgp, id, bgap_mask_ctrl, mask_counter_delay_mask, rval);
786 spin_unlock(&bgp->lock);
792 * ti_bandgap_write_counter() - set the bandgap sensor counter
793 * @bgp: pointer to bandgap instance
795 * @interval: desired update interval in miliseconds
797 static void ti_bandgap_write_counter(struct ti_bandgap *bgp, int id,
800 interval = interval * bgp->clk_rate / 1000;
801 spin_lock(&bgp->lock);
802 RMW_BITS(bgp, id, bgap_counter, counter_mask, interval);
803 spin_unlock(&bgp->lock);
807 * ti_bandgap_write_update_interval() - set the update interval
808 * @bgp: pointer to bandgap instance
810 * @interval: desired update interval in miliseconds
812 * Return: 0 on success or the proper error code
814 int ti_bandgap_write_update_interval(struct ti_bandgap *bgp,
815 int id, u32 interval)
817 int ret = ti_bandgap_validate(bgp, id);
821 if (!TI_BANDGAP_HAS(bgp, COUNTER) &&
822 !TI_BANDGAP_HAS(bgp, COUNTER_DELAY)) {
827 if (TI_BANDGAP_HAS(bgp, COUNTER)) {
828 ti_bandgap_write_counter(bgp, id, interval);
832 ret = ti_bandgap_write_counter_delay(bgp, id, interval);
838 * ti_bandgap_read_temperature() - report current temperature
839 * @bgp: pointer to bandgap instance
841 * @temperature: resulting temperature
843 * Return: 0 on success or the proper error code
845 int ti_bandgap_read_temperature(struct ti_bandgap *bgp, int id,
851 ret = ti_bandgap_validate(bgp, id);
855 spin_lock(&bgp->lock);
856 temp = ti_bandgap_read_temp(bgp, id);
857 spin_unlock(&bgp->lock);
859 ret |= ti_bandgap_adc_to_mcelsius(bgp, temp, &temp);
869 * ti_bandgap_set_sensor_data() - helper function to store thermal
870 * framework related data.
871 * @bgp: pointer to bandgap instance
873 * @data: thermal framework related data to be stored
875 * Return: 0 on success or the proper error code
877 int ti_bandgap_set_sensor_data(struct ti_bandgap *bgp, int id, void *data)
879 int ret = ti_bandgap_validate(bgp, id);
883 bgp->regval[id].data = data;
889 * ti_bandgap_get_sensor_data() - helper function to get thermal
890 * framework related data.
891 * @bgp: pointer to bandgap instance
894 * Return: data stored by set function with sensor id on success or NULL
896 void *ti_bandgap_get_sensor_data(struct ti_bandgap *bgp, int id)
898 int ret = ti_bandgap_validate(bgp, id);
902 return bgp->regval[id].data;
905 /*** Helper functions used during device initialization ***/
908 * ti_bandgap_force_single_read() - executes 1 single ADC conversion
909 * @bgp: pointer to struct ti_bandgap
910 * @id: sensor id which it is desired to read 1 temperature
912 * Used to initialize the conversion state machine and set it to a valid
913 * state. Called during device initialization and context restore events.
918 ti_bandgap_force_single_read(struct ti_bandgap *bgp, int id)
920 u32 temp = 0, counter = 1000;
922 /* Select single conversion mode */
923 if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
924 RMW_BITS(bgp, id, bgap_mode_ctrl, mode_ctrl_mask, 0);
926 /* Start of Conversion = 1 */
927 RMW_BITS(bgp, id, temp_sensor_ctrl, bgap_soc_mask, 1);
928 /* Wait until DTEMP is updated */
929 temp = ti_bandgap_read_temp(bgp, id);
931 while ((temp == 0) && --counter)
932 temp = ti_bandgap_read_temp(bgp, id);
933 /* REVISIT: Check correct condition for end of conversion */
935 /* Start of Conversion = 0 */
936 RMW_BITS(bgp, id, temp_sensor_ctrl, bgap_soc_mask, 0);
942 * ti_bandgap_set_continous_mode() - One time enabling of continuous mode
943 * @bgp: pointer to struct ti_bandgap
945 * Call this function only if HAS(MODE_CONFIG) is set. As this driver may
946 * be used for junction temperature monitoring, it is desirable that the
947 * sensors are operational all the time, so that alerts are generated
952 static int ti_bandgap_set_continuous_mode(struct ti_bandgap *bgp)
956 for (i = 0; i < bgp->conf->sensor_count; i++) {
957 /* Perform a single read just before enabling continuous */
958 ti_bandgap_force_single_read(bgp, i);
959 RMW_BITS(bgp, i, bgap_mode_ctrl, mode_ctrl_mask, 1);
966 * ti_bandgap_get_trend() - To fetch the temperature trend of a sensor
967 * @bgp: pointer to struct ti_bandgap
968 * @id: id of the individual sensor
969 * @trend: Pointer to trend.
971 * This function needs to be called to fetch the temperature trend of a
972 * Particular sensor. The function computes the difference in temperature
973 * w.r.t time. For the bandgaps with built in history buffer the temperatures
974 * are read from the buffer and for those without the Buffer -ENOTSUPP is
977 * Return: 0 if no error, else return corresponding error. If no
978 * error then the trend value is passed on to trend parameter
980 int ti_bandgap_get_trend(struct ti_bandgap *bgp, int id, int *trend)
982 struct temp_sensor_registers *tsr;
983 u32 temp1, temp2, reg1, reg2;
984 int t1, t2, interval, ret = 0;
986 ret = ti_bandgap_validate(bgp, id);
990 if (!TI_BANDGAP_HAS(bgp, HISTORY_BUFFER) ||
991 !TI_BANDGAP_HAS(bgp, FREEZE_BIT)) {
996 spin_lock(&bgp->lock);
998 tsr = bgp->conf->sensors[id].registers;
1000 /* Freeze and read the last 2 valid readings */
1001 RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 1);
1002 reg1 = tsr->ctrl_dtemp_1;
1003 reg2 = tsr->ctrl_dtemp_2;
1005 /* read temperature from history buffer */
1006 temp1 = ti_bandgap_readl(bgp, reg1);
1007 temp1 &= tsr->bgap_dtemp_mask;
1009 temp2 = ti_bandgap_readl(bgp, reg2);
1010 temp2 &= tsr->bgap_dtemp_mask;
1012 /* Convert from adc values to mCelsius temperature */
1013 ret = ti_bandgap_adc_to_mcelsius(bgp, temp1, &t1);
1017 ret = ti_bandgap_adc_to_mcelsius(bgp, temp2, &t2);
1021 /* Fetch the update interval */
1022 ret = ti_bandgap_read_update_interval(bgp, id, &interval);
1023 if (ret || !interval)
1026 *trend = (t1 - t2) / interval;
1028 dev_dbg(bgp->dev, "The temperatures are t1 = %d and t2 = %d and trend =%d\n",
1032 RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 0);
1033 spin_unlock(&bgp->lock);
1039 * ti_bandgap_tshut_init() - setup and initialize tshut handling
1040 * @bgp: pointer to struct ti_bandgap
1041 * @pdev: pointer to device struct platform_device
1043 * Call this function only in case the bandgap features HAS(TSHUT).
1044 * In this case, the driver needs to handle the TSHUT signal as an IRQ.
1045 * The IRQ is wired as a GPIO, and for this purpose, it is required
1046 * to specify which GPIO line is used. TSHUT IRQ is fired anytime
1047 * one of the bandgap sensors violates the TSHUT high/hot threshold.
1048 * And in that case, the system must go off.
1050 * Return: 0 if no error, else error status
1052 static int ti_bandgap_tshut_init(struct ti_bandgap *bgp,
1053 struct platform_device *pdev)
1055 int gpio_nr = bgp->tshut_gpio;
1058 /* Request for gpio_86 line */
1059 status = gpio_request(gpio_nr, "tshut");
1061 dev_err(bgp->dev, "Could not request for TSHUT GPIO:%i\n", 86);
1064 status = gpio_direction_input(gpio_nr);
1066 dev_err(bgp->dev, "Cannot set input TSHUT GPIO %d\n", gpio_nr);
1070 status = request_irq(gpio_to_irq(gpio_nr), ti_bandgap_tshut_irq_handler,
1071 IRQF_TRIGGER_RISING, "tshut", NULL);
1074 dev_err(bgp->dev, "request irq failed for TSHUT");
1081 * ti_bandgap_alert_init() - setup and initialize talert handling
1082 * @bgp: pointer to struct ti_bandgap
1083 * @pdev: pointer to device struct platform_device
1085 * Call this function only in case the bandgap features HAS(TALERT).
1086 * In this case, the driver needs to handle the TALERT signals as an IRQs.
1087 * TALERT is a normal IRQ and it is fired any time thresholds (hot or cold)
1088 * are violated. In these situation, the driver must reprogram the thresholds,
1089 * accordingly to specified policy.
1091 * Return: 0 if no error, else return corresponding error.
1093 static int ti_bandgap_talert_init(struct ti_bandgap *bgp,
1094 struct platform_device *pdev)
1098 bgp->irq = platform_get_irq(pdev, 0);
1100 dev_err(&pdev->dev, "get_irq failed\n");
1103 ret = request_threaded_irq(bgp->irq, NULL,
1104 ti_bandgap_talert_irq_handler,
1105 IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
1108 dev_err(&pdev->dev, "Request threaded irq failed.\n");
1115 static const struct of_device_id of_ti_bandgap_match[];
1117 * ti_bandgap_build() - parse DT and setup a struct ti_bandgap
1118 * @pdev: pointer to device struct platform_device
1120 * Used to read the device tree properties accordingly to the bandgap
1121 * matching version. Based on bandgap version and its capabilities it
1122 * will build a struct ti_bandgap out of the required DT entries.
1124 * Return: valid bandgap structure if successful, else returns ERR_PTR
1125 * return value must be verified with IS_ERR.
1127 static struct ti_bandgap *ti_bandgap_build(struct platform_device *pdev)
1129 struct device_node *node = pdev->dev.of_node;
1130 const struct of_device_id *of_id;
1131 struct ti_bandgap *bgp;
1132 struct resource *res;
1135 /* just for the sake */
1137 dev_err(&pdev->dev, "no platform information available\n");
1138 return ERR_PTR(-EINVAL);
1141 bgp = devm_kzalloc(&pdev->dev, sizeof(*bgp), GFP_KERNEL);
1143 dev_err(&pdev->dev, "Unable to allocate mem for driver ref\n");
1144 return ERR_PTR(-ENOMEM);
1147 of_id = of_match_device(of_ti_bandgap_match, &pdev->dev);
1149 bgp->conf = of_id->data;
1151 /* register shadow for context save and restore */
1152 bgp->regval = devm_kzalloc(&pdev->dev, sizeof(*bgp->regval) *
1153 bgp->conf->sensor_count, GFP_KERNEL);
1155 dev_err(&pdev->dev, "Unable to allocate mem for driver ref\n");
1156 return ERR_PTR(-ENOMEM);
1161 void __iomem *chunk;
1163 res = platform_get_resource(pdev, IORESOURCE_MEM, i);
1166 chunk = devm_ioremap_resource(&pdev->dev, res);
1170 return ERR_CAST(chunk);
1175 if (TI_BANDGAP_HAS(bgp, TSHUT)) {
1176 bgp->tshut_gpio = of_get_gpio(node, 0);
1177 if (!gpio_is_valid(bgp->tshut_gpio)) {
1178 dev_err(&pdev->dev, "invalid gpio for tshut (%d)\n",
1180 return ERR_PTR(-EINVAL);
1187 /*** Device driver call backs ***/
1190 int ti_bandgap_probe(struct platform_device *pdev)
1192 struct ti_bandgap *bgp;
1193 int clk_rate, ret = 0, i;
1195 bgp = ti_bandgap_build(pdev);
1197 dev_err(&pdev->dev, "failed to fetch platform data\n");
1198 return PTR_ERR(bgp);
1200 bgp->dev = &pdev->dev;
1202 if (TI_BANDGAP_HAS(bgp, TSHUT)) {
1203 ret = ti_bandgap_tshut_init(bgp, pdev);
1206 "failed to initialize system tshut IRQ\n");
1211 bgp->fclock = clk_get(NULL, bgp->conf->fclock_name);
1212 ret = IS_ERR(bgp->fclock);
1214 dev_err(&pdev->dev, "failed to request fclock reference\n");
1215 ret = PTR_ERR(bgp->fclock);
1219 bgp->div_clk = clk_get(NULL, bgp->conf->div_ck_name);
1220 ret = IS_ERR(bgp->div_clk);
1223 "failed to request div_ts_ck clock ref\n");
1224 ret = PTR_ERR(bgp->div_clk);
1228 for (i = 0; i < bgp->conf->sensor_count; i++) {
1229 struct temp_sensor_registers *tsr;
1232 tsr = bgp->conf->sensors[i].registers;
1234 * check if the efuse has a non-zero value if not
1235 * it is an untrimmed sample and the temperatures
1236 * may not be accurate
1238 val = ti_bandgap_readl(bgp, tsr->bgap_efuse);
1240 dev_info(&pdev->dev,
1241 "Non-trimmed BGAP, Temp not accurate\n");
1244 clk_rate = clk_round_rate(bgp->div_clk,
1245 bgp->conf->sensors[0].ts_data->max_freq);
1246 if (clk_rate < bgp->conf->sensors[0].ts_data->min_freq ||
1247 clk_rate == 0xffffffff) {
1249 dev_err(&pdev->dev, "wrong clock rate (%d)\n", clk_rate);
1253 ret = clk_set_rate(bgp->div_clk, clk_rate);
1255 dev_err(&pdev->dev, "Cannot re-set clock rate. Continuing\n");
1257 bgp->clk_rate = clk_rate;
1258 if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1259 clk_prepare_enable(bgp->fclock);
1262 spin_lock_init(&bgp->lock);
1263 bgp->dev = &pdev->dev;
1264 platform_set_drvdata(pdev, bgp);
1266 ti_bandgap_power(bgp, true);
1268 /* Set default counter to 1 for now */
1269 if (TI_BANDGAP_HAS(bgp, COUNTER))
1270 for (i = 0; i < bgp->conf->sensor_count; i++)
1271 RMW_BITS(bgp, i, bgap_counter, counter_mask, 1);
1273 /* Set default thresholds for alert and shutdown */
1274 for (i = 0; i < bgp->conf->sensor_count; i++) {
1275 struct temp_sensor_data *ts_data;
1277 ts_data = bgp->conf->sensors[i].ts_data;
1279 if (TI_BANDGAP_HAS(bgp, TALERT)) {
1280 /* Set initial Talert thresholds */
1281 RMW_BITS(bgp, i, bgap_threshold,
1282 threshold_tcold_mask, ts_data->t_cold);
1283 RMW_BITS(bgp, i, bgap_threshold,
1284 threshold_thot_mask, ts_data->t_hot);
1285 /* Enable the alert events */
1286 RMW_BITS(bgp, i, bgap_mask_ctrl, mask_hot_mask, 1);
1287 RMW_BITS(bgp, i, bgap_mask_ctrl, mask_cold_mask, 1);
1290 if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG)) {
1291 /* Set initial Tshut thresholds */
1292 RMW_BITS(bgp, i, tshut_threshold,
1293 tshut_hot_mask, ts_data->tshut_hot);
1294 RMW_BITS(bgp, i, tshut_threshold,
1295 tshut_cold_mask, ts_data->tshut_cold);
1299 if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
1300 ti_bandgap_set_continuous_mode(bgp);
1302 /* Set .250 seconds time as default counter */
1303 if (TI_BANDGAP_HAS(bgp, COUNTER))
1304 for (i = 0; i < bgp->conf->sensor_count; i++)
1305 RMW_BITS(bgp, i, bgap_counter, counter_mask,
1308 /* Every thing is good? Then expose the sensors */
1309 for (i = 0; i < bgp->conf->sensor_count; i++) {
1312 if (bgp->conf->sensors[i].register_cooling) {
1313 ret = bgp->conf->sensors[i].register_cooling(bgp, i);
1315 goto remove_sensors;
1318 if (bgp->conf->expose_sensor) {
1319 domain = bgp->conf->sensors[i].domain;
1320 ret = bgp->conf->expose_sensor(bgp, i, domain);
1322 goto remove_last_cooling;
1327 * Enable the Interrupts once everything is set. Otherwise irq handler
1328 * might be called as soon as it is enabled where as rest of framework
1329 * is still getting initialised.
1331 if (TI_BANDGAP_HAS(bgp, TALERT)) {
1332 ret = ti_bandgap_talert_init(bgp, pdev);
1334 dev_err(&pdev->dev, "failed to initialize Talert IRQ\n");
1335 i = bgp->conf->sensor_count;
1342 remove_last_cooling:
1343 if (bgp->conf->sensors[i].unregister_cooling)
1344 bgp->conf->sensors[i].unregister_cooling(bgp, i);
1346 for (i--; i >= 0; i--) {
1347 if (bgp->conf->sensors[i].unregister_cooling)
1348 bgp->conf->sensors[i].unregister_cooling(bgp, i);
1349 if (bgp->conf->remove_sensor)
1350 bgp->conf->remove_sensor(bgp, i);
1352 ti_bandgap_power(bgp, false);
1354 if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1355 clk_disable_unprepare(bgp->fclock);
1357 clk_put(bgp->fclock);
1358 clk_put(bgp->div_clk);
1360 if (TI_BANDGAP_HAS(bgp, TSHUT)) {
1361 free_irq(gpio_to_irq(bgp->tshut_gpio), NULL);
1362 gpio_free(bgp->tshut_gpio);
1369 int ti_bandgap_remove(struct platform_device *pdev)
1371 struct ti_bandgap *bgp = platform_get_drvdata(pdev);
1374 /* First thing is to remove sensor interfaces */
1375 for (i = 0; i < bgp->conf->sensor_count; i++) {
1376 if (bgp->conf->sensors[i].unregister_cooling)
1377 bgp->conf->sensors[i].unregister_cooling(bgp, i);
1379 if (bgp->conf->remove_sensor)
1380 bgp->conf->remove_sensor(bgp, i);
1383 ti_bandgap_power(bgp, false);
1385 if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1386 clk_disable_unprepare(bgp->fclock);
1387 clk_put(bgp->fclock);
1388 clk_put(bgp->div_clk);
1390 if (TI_BANDGAP_HAS(bgp, TALERT))
1391 free_irq(bgp->irq, bgp);
1393 if (TI_BANDGAP_HAS(bgp, TSHUT)) {
1394 free_irq(gpio_to_irq(bgp->tshut_gpio), NULL);
1395 gpio_free(bgp->tshut_gpio);
1402 static int ti_bandgap_save_ctxt(struct ti_bandgap *bgp)
1406 for (i = 0; i < bgp->conf->sensor_count; i++) {
1407 struct temp_sensor_registers *tsr;
1408 struct temp_sensor_regval *rval;
1410 rval = &bgp->regval[i];
1411 tsr = bgp->conf->sensors[i].registers;
1413 if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
1414 rval->bg_mode_ctrl = ti_bandgap_readl(bgp,
1415 tsr->bgap_mode_ctrl);
1416 if (TI_BANDGAP_HAS(bgp, COUNTER))
1417 rval->bg_counter = ti_bandgap_readl(bgp,
1419 if (TI_BANDGAP_HAS(bgp, TALERT)) {
1420 rval->bg_threshold = ti_bandgap_readl(bgp,
1421 tsr->bgap_threshold);
1422 rval->bg_ctrl = ti_bandgap_readl(bgp,
1423 tsr->bgap_mask_ctrl);
1426 if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG))
1427 rval->tshut_threshold = ti_bandgap_readl(bgp,
1428 tsr->tshut_threshold);
1434 static int ti_bandgap_restore_ctxt(struct ti_bandgap *bgp)
1438 for (i = 0; i < bgp->conf->sensor_count; i++) {
1439 struct temp_sensor_registers *tsr;
1440 struct temp_sensor_regval *rval;
1443 rval = &bgp->regval[i];
1444 tsr = bgp->conf->sensors[i].registers;
1446 if (TI_BANDGAP_HAS(bgp, COUNTER))
1447 val = ti_bandgap_readl(bgp, tsr->bgap_counter);
1449 if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG))
1450 ti_bandgap_writel(bgp, rval->tshut_threshold,
1451 tsr->tshut_threshold);
1452 /* Force immediate temperature measurement and update
1453 * of the DTEMP field
1455 ti_bandgap_force_single_read(bgp, i);
1457 if (TI_BANDGAP_HAS(bgp, COUNTER))
1458 ti_bandgap_writel(bgp, rval->bg_counter,
1460 if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
1461 ti_bandgap_writel(bgp, rval->bg_mode_ctrl,
1462 tsr->bgap_mode_ctrl);
1463 if (TI_BANDGAP_HAS(bgp, TALERT)) {
1464 ti_bandgap_writel(bgp, rval->bg_threshold,
1465 tsr->bgap_threshold);
1466 ti_bandgap_writel(bgp, rval->bg_ctrl,
1467 tsr->bgap_mask_ctrl);
1474 static int ti_bandgap_suspend(struct device *dev)
1476 struct ti_bandgap *bgp = dev_get_drvdata(dev);
1479 err = ti_bandgap_save_ctxt(bgp);
1480 ti_bandgap_power(bgp, false);
1482 if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1483 clk_disable_unprepare(bgp->fclock);
1488 static int ti_bandgap_resume(struct device *dev)
1490 struct ti_bandgap *bgp = dev_get_drvdata(dev);
1492 if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
1493 clk_prepare_enable(bgp->fclock);
1495 ti_bandgap_power(bgp, true);
1497 return ti_bandgap_restore_ctxt(bgp);
1499 static const struct dev_pm_ops ti_bandgap_dev_pm_ops = {
1500 SET_SYSTEM_SLEEP_PM_OPS(ti_bandgap_suspend,
1504 #define DEV_PM_OPS (&ti_bandgap_dev_pm_ops)
1506 #define DEV_PM_OPS NULL
1509 static const struct of_device_id of_ti_bandgap_match[] = {
1510 #ifdef CONFIG_OMAP4_THERMAL
1512 .compatible = "ti,omap4430-bandgap",
1513 .data = (void *)&omap4430_data,
1516 .compatible = "ti,omap4460-bandgap",
1517 .data = (void *)&omap4460_data,
1520 .compatible = "ti,omap4470-bandgap",
1521 .data = (void *)&omap4470_data,
1524 #ifdef CONFIG_OMAP5_THERMAL
1526 .compatible = "ti,omap5430-bandgap",
1527 .data = (void *)&omap5430_data,
1530 #ifdef CONFIG_DRA752_THERMAL
1532 .compatible = "ti,dra752-bandgap",
1533 .data = (void *)&dra752_data,
1539 MODULE_DEVICE_TABLE(of, of_ti_bandgap_match);
1541 static struct platform_driver ti_bandgap_sensor_driver = {
1542 .probe = ti_bandgap_probe,
1543 .remove = ti_bandgap_remove,
1545 .name = "ti-soc-thermal",
1547 .of_match_table = of_ti_bandgap_match,
1551 module_platform_driver(ti_bandgap_sensor_driver);
1553 MODULE_DESCRIPTION("OMAP4+ bandgap temperature sensor driver");
1554 MODULE_LICENSE("GPL v2");
1555 MODULE_ALIAS("platform:ti-soc-thermal");
1556 MODULE_AUTHOR("Texas Instrument Inc.");