2 * drivers/iio/light/tsl2563.c
4 * Copyright (C) 2008 Nokia Corporation
6 * Written by Timo O. Karjalainen <timo.o.karjalainen@nokia.com>
7 * Contact: Amit Kucheria <amit.kucheria@verdurent.com>
9 * Converted to IIO driver
10 * Amit Kucheria <amit.kucheria@verdurent.com>
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * version 2 as published by the Free Software Foundation.
16 * This program is distributed in the hope that it will be useful, but
17 * WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 * General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
27 #include <linux/module.h>
28 #include <linux/i2c.h>
29 #include <linux/interrupt.h>
30 #include <linux/irq.h>
31 #include <linux/sched.h>
32 #include <linux/mutex.h>
33 #include <linux/delay.h>
35 #include <linux/err.h>
36 #include <linux/slab.h>
38 #include <linux/iio/iio.h>
39 #include <linux/iio/sysfs.h>
40 #include <linux/iio/events.h>
41 #include <linux/platform_data/tsl2563.h>
43 /* Use this many bits for fraction part. */
44 #define ADC_FRAC_BITS 14
46 /* Given number of 1/10000's in ADC_FRAC_BITS precision. */
47 #define FRAC10K(f) (((f) * (1L << (ADC_FRAC_BITS))) / (10000))
49 /* Bits used for fraction in calibration coefficients.*/
50 #define CALIB_FRAC_BITS 10
51 /* 0.5 in CALIB_FRAC_BITS precision */
52 #define CALIB_FRAC_HALF (1 << (CALIB_FRAC_BITS - 1))
53 /* Make a fraction from a number n that was multiplied with b. */
54 #define CALIB_FRAC(n, b) (((n) << CALIB_FRAC_BITS) / (b))
55 /* Decimal 10^(digits in sysfs presentation) */
56 #define CALIB_BASE_SYSFS 1000
58 #define TSL2563_CMD 0x80
59 #define TSL2563_CLEARINT 0x40
61 #define TSL2563_REG_CTRL 0x00
62 #define TSL2563_REG_TIMING 0x01
63 #define TSL2563_REG_LOWLOW 0x02 /* data0 low threshold, 2 bytes */
64 #define TSL2563_REG_LOWHIGH 0x03
65 #define TSL2563_REG_HIGHLOW 0x04 /* data0 high threshold, 2 bytes */
66 #define TSL2563_REG_HIGHHIGH 0x05
67 #define TSL2563_REG_INT 0x06
68 #define TSL2563_REG_ID 0x0a
69 #define TSL2563_REG_DATA0LOW 0x0c /* broadband sensor value, 2 bytes */
70 #define TSL2563_REG_DATA0HIGH 0x0d
71 #define TSL2563_REG_DATA1LOW 0x0e /* infrared sensor value, 2 bytes */
72 #define TSL2563_REG_DATA1HIGH 0x0f
74 #define TSL2563_CMD_POWER_ON 0x03
75 #define TSL2563_CMD_POWER_OFF 0x00
76 #define TSL2563_CTRL_POWER_MASK 0x03
78 #define TSL2563_TIMING_13MS 0x00
79 #define TSL2563_TIMING_100MS 0x01
80 #define TSL2563_TIMING_400MS 0x02
81 #define TSL2563_TIMING_MASK 0x03
82 #define TSL2563_TIMING_GAIN16 0x10
83 #define TSL2563_TIMING_GAIN1 0x00
85 #define TSL2563_INT_DISBLED 0x00
86 #define TSL2563_INT_LEVEL 0x10
87 #define TSL2563_INT_PERSIST(n) ((n) & 0x0F)
89 struct tsl2563_gainlevel_coeff {
95 static const struct tsl2563_gainlevel_coeff tsl2563_gainlevel_table[] = {
97 .gaintime = TSL2563_TIMING_400MS | TSL2563_TIMING_GAIN16,
101 .gaintime = TSL2563_TIMING_400MS | TSL2563_TIMING_GAIN1,
105 .gaintime = TSL2563_TIMING_100MS | TSL2563_TIMING_GAIN1,
109 .gaintime = TSL2563_TIMING_13MS | TSL2563_TIMING_GAIN1,
115 struct tsl2563_chip {
117 struct i2c_client *client;
118 struct delayed_work poweroff_work;
120 /* Remember state for suspend and resume functions */
123 struct tsl2563_gainlevel_coeff const *gainlevel;
130 /* Calibration coefficients */
135 /* Cache current values, to be returned while suspended */
140 static int tsl2563_set_power(struct tsl2563_chip *chip, int on)
142 struct i2c_client *client = chip->client;
145 cmd = on ? TSL2563_CMD_POWER_ON : TSL2563_CMD_POWER_OFF;
146 return i2c_smbus_write_byte_data(client,
147 TSL2563_CMD | TSL2563_REG_CTRL, cmd);
151 * Return value is 0 for off, 1 for on, or a negative error
152 * code if reading failed.
154 static int tsl2563_get_power(struct tsl2563_chip *chip)
156 struct i2c_client *client = chip->client;
159 ret = i2c_smbus_read_byte_data(client, TSL2563_CMD | TSL2563_REG_CTRL);
163 return (ret & TSL2563_CTRL_POWER_MASK) == TSL2563_CMD_POWER_ON;
166 static int tsl2563_configure(struct tsl2563_chip *chip)
170 ret = i2c_smbus_write_byte_data(chip->client,
171 TSL2563_CMD | TSL2563_REG_TIMING,
172 chip->gainlevel->gaintime);
175 ret = i2c_smbus_write_byte_data(chip->client,
176 TSL2563_CMD | TSL2563_REG_HIGHLOW,
177 chip->high_thres & 0xFF);
180 ret = i2c_smbus_write_byte_data(chip->client,
181 TSL2563_CMD | TSL2563_REG_HIGHHIGH,
182 (chip->high_thres >> 8) & 0xFF);
185 ret = i2c_smbus_write_byte_data(chip->client,
186 TSL2563_CMD | TSL2563_REG_LOWLOW,
187 chip->low_thres & 0xFF);
190 ret = i2c_smbus_write_byte_data(chip->client,
191 TSL2563_CMD | TSL2563_REG_LOWHIGH,
192 (chip->low_thres >> 8) & 0xFF);
194 * Interrupt register is automatically written anyway if it is relevant
201 static void tsl2563_poweroff_work(struct work_struct *work)
203 struct tsl2563_chip *chip =
204 container_of(work, struct tsl2563_chip, poweroff_work.work);
205 tsl2563_set_power(chip, 0);
208 static int tsl2563_detect(struct tsl2563_chip *chip)
212 ret = tsl2563_set_power(chip, 1);
216 ret = tsl2563_get_power(chip);
220 return ret ? 0 : -ENODEV;
223 static int tsl2563_read_id(struct tsl2563_chip *chip, u8 *id)
225 struct i2c_client *client = chip->client;
228 ret = i2c_smbus_read_byte_data(client, TSL2563_CMD | TSL2563_REG_ID);
238 * "Normalized" ADC value is one obtained with 400ms of integration time and
239 * 16x gain. This function returns the number of bits of shift needed to
240 * convert between normalized values and HW values obtained using given
241 * timing and gain settings.
243 static int adc_shiftbits(u8 timing)
247 switch (timing & TSL2563_TIMING_MASK) {
248 case TSL2563_TIMING_13MS:
251 case TSL2563_TIMING_100MS:
254 case TSL2563_TIMING_400MS:
259 if (!(timing & TSL2563_TIMING_GAIN16))
265 /* Convert a HW ADC value to normalized scale. */
266 static u32 normalize_adc(u16 adc, u8 timing)
268 return adc << adc_shiftbits(timing);
271 static void tsl2563_wait_adc(struct tsl2563_chip *chip)
275 switch (chip->gainlevel->gaintime & TSL2563_TIMING_MASK) {
276 case TSL2563_TIMING_13MS:
279 case TSL2563_TIMING_100MS:
286 * TODO: Make sure that we wait at least required delay but why we
287 * have to extend it one tick more?
289 schedule_timeout_interruptible(msecs_to_jiffies(delay) + 2);
292 static int tsl2563_adjust_gainlevel(struct tsl2563_chip *chip, u16 adc)
294 struct i2c_client *client = chip->client;
296 if (adc > chip->gainlevel->max || adc < chip->gainlevel->min) {
298 (adc > chip->gainlevel->max) ?
299 chip->gainlevel++ : chip->gainlevel--;
301 i2c_smbus_write_byte_data(client,
302 TSL2563_CMD | TSL2563_REG_TIMING,
303 chip->gainlevel->gaintime);
305 tsl2563_wait_adc(chip);
306 tsl2563_wait_adc(chip);
313 static int tsl2563_get_adc(struct tsl2563_chip *chip)
315 struct i2c_client *client = chip->client;
323 if (!chip->int_enabled) {
324 cancel_delayed_work(&chip->poweroff_work);
326 if (!tsl2563_get_power(chip)) {
327 ret = tsl2563_set_power(chip, 1);
330 ret = tsl2563_configure(chip);
333 tsl2563_wait_adc(chip);
338 ret = i2c_smbus_read_word_data(client,
339 TSL2563_CMD | TSL2563_REG_DATA0LOW);
344 ret = i2c_smbus_read_word_data(client,
345 TSL2563_CMD | TSL2563_REG_DATA1LOW);
350 retry = tsl2563_adjust_gainlevel(chip, adc0);
353 chip->data0 = normalize_adc(adc0, chip->gainlevel->gaintime);
354 chip->data1 = normalize_adc(adc1, chip->gainlevel->gaintime);
356 if (!chip->int_enabled)
357 schedule_delayed_work(&chip->poweroff_work, 5 * HZ);
364 static inline int calib_to_sysfs(u32 calib)
366 return (int) (((calib * CALIB_BASE_SYSFS) +
367 CALIB_FRAC_HALF) >> CALIB_FRAC_BITS);
370 static inline u32 calib_from_sysfs(int value)
372 return (((u32) value) << CALIB_FRAC_BITS) / CALIB_BASE_SYSFS;
376 * Conversions between lux and ADC values.
378 * The basic formula is lux = c0 * adc0 - c1 * adc1, where c0 and c1 are
379 * appropriate constants. Different constants are needed for different
380 * kinds of light, determined by the ratio adc1/adc0 (basically the ratio
381 * of the intensities in infrared and visible wavelengths). lux_table below
382 * lists the upper threshold of the adc1/adc0 ratio and the corresponding
386 struct tsl2563_lux_coeff {
387 unsigned long ch_ratio;
388 unsigned long ch0_coeff;
389 unsigned long ch1_coeff;
392 static const struct tsl2563_lux_coeff lux_table[] = {
394 .ch_ratio = FRAC10K(1300),
395 .ch0_coeff = FRAC10K(315),
396 .ch1_coeff = FRAC10K(262),
398 .ch_ratio = FRAC10K(2600),
399 .ch0_coeff = FRAC10K(337),
400 .ch1_coeff = FRAC10K(430),
402 .ch_ratio = FRAC10K(3900),
403 .ch0_coeff = FRAC10K(363),
404 .ch1_coeff = FRAC10K(529),
406 .ch_ratio = FRAC10K(5200),
407 .ch0_coeff = FRAC10K(392),
408 .ch1_coeff = FRAC10K(605),
410 .ch_ratio = FRAC10K(6500),
411 .ch0_coeff = FRAC10K(229),
412 .ch1_coeff = FRAC10K(291),
414 .ch_ratio = FRAC10K(8000),
415 .ch0_coeff = FRAC10K(157),
416 .ch1_coeff = FRAC10K(180),
418 .ch_ratio = FRAC10K(13000),
419 .ch0_coeff = FRAC10K(34),
420 .ch1_coeff = FRAC10K(26),
422 .ch_ratio = ULONG_MAX,
428 /* Convert normalized, scaled ADC values to lux. */
429 static unsigned int adc_to_lux(u32 adc0, u32 adc1)
431 const struct tsl2563_lux_coeff *lp = lux_table;
432 unsigned long ratio, lux, ch0 = adc0, ch1 = adc1;
434 ratio = ch0 ? ((ch1 << ADC_FRAC_BITS) / ch0) : ULONG_MAX;
436 while (lp->ch_ratio < ratio)
439 lux = ch0 * lp->ch0_coeff - ch1 * lp->ch1_coeff;
441 return (unsigned int) (lux >> ADC_FRAC_BITS);
444 /* Apply calibration coefficient to ADC count. */
445 static u32 calib_adc(u32 adc, u32 calib)
447 unsigned long scaled = adc;
450 scaled >>= CALIB_FRAC_BITS;
455 static int tsl2563_write_raw(struct iio_dev *indio_dev,
456 struct iio_chan_spec const *chan,
461 struct tsl2563_chip *chip = iio_priv(indio_dev);
463 if (chan->channel == IIO_MOD_LIGHT_BOTH)
464 chip->calib0 = calib_from_sysfs(val);
466 chip->calib1 = calib_from_sysfs(val);
471 static int tsl2563_read_raw(struct iio_dev *indio_dev,
472 struct iio_chan_spec const *chan,
479 struct tsl2563_chip *chip = iio_priv(indio_dev);
481 mutex_lock(&chip->lock);
483 case IIO_CHAN_INFO_RAW:
484 case IIO_CHAN_INFO_PROCESSED:
485 switch (chan->type) {
487 ret = tsl2563_get_adc(chip);
490 calib0 = calib_adc(chip->data0, chip->calib0) *
491 chip->cover_comp_gain;
492 calib1 = calib_adc(chip->data1, chip->calib1) *
493 chip->cover_comp_gain;
494 *val = adc_to_lux(calib0, calib1);
498 ret = tsl2563_get_adc(chip);
501 if (chan->channel == 0)
512 case IIO_CHAN_INFO_CALIBSCALE:
513 if (chan->channel == 0)
514 *val = calib_to_sysfs(chip->calib0);
516 *val = calib_to_sysfs(chip->calib1);
525 mutex_unlock(&chip->lock);
529 static const struct iio_chan_spec tsl2563_channels[] = {
533 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
536 .type = IIO_INTENSITY,
538 .channel2 = IIO_MOD_LIGHT_BOTH,
539 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
540 BIT(IIO_CHAN_INFO_CALIBSCALE),
541 .event_mask = (IIO_EV_BIT(IIO_EV_TYPE_THRESH,
543 IIO_EV_BIT(IIO_EV_TYPE_THRESH,
544 IIO_EV_DIR_FALLING)),
546 .type = IIO_INTENSITY,
548 .channel2 = IIO_MOD_LIGHT_IR,
549 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
550 BIT(IIO_CHAN_INFO_CALIBSCALE),
554 static int tsl2563_read_thresh(struct iio_dev *indio_dev,
558 struct tsl2563_chip *chip = iio_priv(indio_dev);
560 switch (IIO_EVENT_CODE_EXTRACT_DIR(event_code)) {
561 case IIO_EV_DIR_RISING:
562 *val = chip->high_thres;
564 case IIO_EV_DIR_FALLING:
565 *val = chip->low_thres;
574 static int tsl2563_write_thresh(struct iio_dev *indio_dev,
578 struct tsl2563_chip *chip = iio_priv(indio_dev);
582 if (IIO_EVENT_CODE_EXTRACT_DIR(event_code) == IIO_EV_DIR_RISING)
583 address = TSL2563_REG_HIGHLOW;
585 address = TSL2563_REG_LOWLOW;
586 mutex_lock(&chip->lock);
587 ret = i2c_smbus_write_byte_data(chip->client, TSL2563_CMD | address,
591 ret = i2c_smbus_write_byte_data(chip->client,
592 TSL2563_CMD | (address + 1),
594 if (IIO_EVENT_CODE_EXTRACT_DIR(event_code) == IIO_EV_DIR_RISING)
595 chip->high_thres = val;
597 chip->low_thres = val;
600 mutex_unlock(&chip->lock);
605 static irqreturn_t tsl2563_event_handler(int irq, void *private)
607 struct iio_dev *dev_info = private;
608 struct tsl2563_chip *chip = iio_priv(dev_info);
610 iio_push_event(dev_info,
611 IIO_UNMOD_EVENT_CODE(IIO_LIGHT,
617 /* clear the interrupt and push the event */
618 i2c_smbus_write_byte(chip->client, TSL2563_CMD | TSL2563_CLEARINT);
622 static int tsl2563_write_interrupt_config(struct iio_dev *indio_dev,
626 struct tsl2563_chip *chip = iio_priv(indio_dev);
629 mutex_lock(&chip->lock);
630 if (state && !(chip->intr & 0x30)) {
633 /* ensure the chip is actually on */
634 cancel_delayed_work(&chip->poweroff_work);
635 if (!tsl2563_get_power(chip)) {
636 ret = tsl2563_set_power(chip, 1);
639 ret = tsl2563_configure(chip);
643 ret = i2c_smbus_write_byte_data(chip->client,
644 TSL2563_CMD | TSL2563_REG_INT,
646 chip->int_enabled = true;
649 if (!state && (chip->intr & 0x30)) {
651 ret = i2c_smbus_write_byte_data(chip->client,
652 TSL2563_CMD | TSL2563_REG_INT,
654 chip->int_enabled = false;
655 /* now the interrupt is not enabled, we can go to sleep */
656 schedule_delayed_work(&chip->poweroff_work, 5 * HZ);
659 mutex_unlock(&chip->lock);
664 static int tsl2563_read_interrupt_config(struct iio_dev *indio_dev,
667 struct tsl2563_chip *chip = iio_priv(indio_dev);
670 mutex_lock(&chip->lock);
671 ret = i2c_smbus_read_byte_data(chip->client,
672 TSL2563_CMD | TSL2563_REG_INT);
673 mutex_unlock(&chip->lock);
677 return !!(ret & 0x30);
680 static const struct iio_info tsl2563_info_no_irq = {
681 .driver_module = THIS_MODULE,
682 .read_raw = &tsl2563_read_raw,
683 .write_raw = &tsl2563_write_raw,
686 static const struct iio_info tsl2563_info = {
687 .driver_module = THIS_MODULE,
688 .read_raw = &tsl2563_read_raw,
689 .write_raw = &tsl2563_write_raw,
690 .read_event_value = &tsl2563_read_thresh,
691 .write_event_value = &tsl2563_write_thresh,
692 .read_event_config = &tsl2563_read_interrupt_config,
693 .write_event_config = &tsl2563_write_interrupt_config,
696 static int tsl2563_probe(struct i2c_client *client,
697 const struct i2c_device_id *device_id)
699 struct iio_dev *indio_dev;
700 struct tsl2563_chip *chip;
701 struct tsl2563_platform_data *pdata = client->dev.platform_data;
705 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
709 chip = iio_priv(indio_dev);
711 i2c_set_clientdata(client, chip);
712 chip->client = client;
714 err = tsl2563_detect(chip);
716 dev_err(&client->dev, "detect error %d\n", -err);
720 err = tsl2563_read_id(chip, &id);
722 dev_err(&client->dev, "read id error %d\n", -err);
726 mutex_init(&chip->lock);
728 /* Default values used until userspace says otherwise */
729 chip->low_thres = 0x0;
730 chip->high_thres = 0xffff;
731 chip->gainlevel = tsl2563_gainlevel_table;
732 chip->intr = TSL2563_INT_PERSIST(4);
733 chip->calib0 = calib_from_sysfs(CALIB_BASE_SYSFS);
734 chip->calib1 = calib_from_sysfs(CALIB_BASE_SYSFS);
737 chip->cover_comp_gain = pdata->cover_comp_gain;
739 chip->cover_comp_gain = 1;
741 dev_info(&client->dev, "model %d, rev. %d\n", id >> 4, id & 0x0f);
742 indio_dev->name = client->name;
743 indio_dev->channels = tsl2563_channels;
744 indio_dev->num_channels = ARRAY_SIZE(tsl2563_channels);
745 indio_dev->dev.parent = &client->dev;
746 indio_dev->modes = INDIO_DIRECT_MODE;
749 indio_dev->info = &tsl2563_info;
751 indio_dev->info = &tsl2563_info_no_irq;
754 err = devm_request_threaded_irq(&client->dev, client->irq,
756 &tsl2563_event_handler,
757 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
761 dev_err(&client->dev, "irq request error %d\n", -err);
766 err = tsl2563_configure(chip);
768 dev_err(&client->dev, "configure error %d\n", -err);
772 INIT_DELAYED_WORK(&chip->poweroff_work, tsl2563_poweroff_work);
774 /* The interrupt cannot yet be enabled so this is fine without lock */
775 schedule_delayed_work(&chip->poweroff_work, 5 * HZ);
777 err = iio_device_register(indio_dev);
779 dev_err(&client->dev, "iio registration error %d\n", -err);
786 cancel_delayed_work(&chip->poweroff_work);
787 flush_scheduled_work();
791 static int tsl2563_remove(struct i2c_client *client)
793 struct tsl2563_chip *chip = i2c_get_clientdata(client);
794 struct iio_dev *indio_dev = iio_priv_to_dev(chip);
796 iio_device_unregister(indio_dev);
797 if (!chip->int_enabled)
798 cancel_delayed_work(&chip->poweroff_work);
799 /* Ensure that interrupts are disabled - then flush any bottom halves */
801 i2c_smbus_write_byte_data(chip->client, TSL2563_CMD | TSL2563_REG_INT,
803 flush_scheduled_work();
804 tsl2563_set_power(chip, 0);
809 #ifdef CONFIG_PM_SLEEP
810 static int tsl2563_suspend(struct device *dev)
812 struct tsl2563_chip *chip = i2c_get_clientdata(to_i2c_client(dev));
815 mutex_lock(&chip->lock);
817 ret = tsl2563_set_power(chip, 0);
821 chip->suspended = true;
824 mutex_unlock(&chip->lock);
828 static int tsl2563_resume(struct device *dev)
830 struct tsl2563_chip *chip = i2c_get_clientdata(to_i2c_client(dev));
833 mutex_lock(&chip->lock);
835 ret = tsl2563_set_power(chip, 1);
839 ret = tsl2563_configure(chip);
843 chip->suspended = false;
846 mutex_unlock(&chip->lock);
850 static SIMPLE_DEV_PM_OPS(tsl2563_pm_ops, tsl2563_suspend, tsl2563_resume);
851 #define TSL2563_PM_OPS (&tsl2563_pm_ops)
853 #define TSL2563_PM_OPS NULL
856 static const struct i2c_device_id tsl2563_id[] = {
863 MODULE_DEVICE_TABLE(i2c, tsl2563_id);
865 static struct i2c_driver tsl2563_i2c_driver = {
868 .pm = TSL2563_PM_OPS,
870 .probe = tsl2563_probe,
871 .remove = tsl2563_remove,
872 .id_table = tsl2563_id,
874 module_i2c_driver(tsl2563_i2c_driver);
876 MODULE_AUTHOR("Nokia Corporation");
877 MODULE_DESCRIPTION("tsl2563 light sensor driver");
878 MODULE_LICENSE("GPL");