2 * drivers/i2c/chips/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/sched.h>
31 #include <linux/mutex.h>
32 #include <linux/delay.h>
33 #include <linux/platform_device.h>
35 #include <linux/hwmon.h>
36 #include <linux/err.h>
41 /* Use this many bits for fraction part. */
42 #define ADC_FRAC_BITS (14)
44 /* Given number of 1/10000's in ADC_FRAC_BITS precision. */
45 #define FRAC10K(f) (((f) * (1L << (ADC_FRAC_BITS))) / (10000))
47 /* Bits used for fraction in calibration coefficients.*/
48 #define CALIB_FRAC_BITS (10)
49 /* 0.5 in CALIB_FRAC_BITS precision */
50 #define CALIB_FRAC_HALF (1 << (CALIB_FRAC_BITS - 1))
51 /* Make a fraction from a number n that was multiplied with b. */
52 #define CALIB_FRAC(n, b) (((n) << CALIB_FRAC_BITS) / (b))
53 /* Decimal 10^(digits in sysfs presentation) */
54 #define CALIB_BASE_SYSFS (1000)
56 #define TSL2563_CMD (0x80)
57 #define TSL2563_CLEARINT (0x40)
59 #define TSL2563_REG_CTRL (0x00)
60 #define TSL2563_REG_TIMING (0x01)
61 #define TSL2563_REG_LOWLOW (0x02) /* data0 low threshold, 2 bytes */
62 #define TSL2563_REG_LOWHIGH (0x03)
63 #define TSL2563_REG_HIGHLOW (0x04) /* data0 high threshold, 2 bytes */
64 #define TSL2563_REG_HIGHHIGH (0x05)
65 #define TSL2563_REG_INT (0x06)
66 #define TSL2563_REG_ID (0x0a)
67 #define TSL2563_REG_DATA0LOW (0x0c) /* broadband sensor value, 2 bytes */
68 #define TSL2563_REG_DATA0HIGH (0x0d)
69 #define TSL2563_REG_DATA1LOW (0x0e) /* infrared sensor value, 2 bytes */
70 #define TSL2563_REG_DATA1HIGH (0x0f)
72 #define TSL2563_CMD_POWER_ON (0x03)
73 #define TSL2563_CMD_POWER_OFF (0x00)
74 #define TSL2563_CTRL_POWER_MASK (0x03)
76 #define TSL2563_TIMING_13MS (0x00)
77 #define TSL2563_TIMING_100MS (0x01)
78 #define TSL2563_TIMING_400MS (0x02)
79 #define TSL2563_TIMING_MASK (0x03)
80 #define TSL2563_TIMING_GAIN16 (0x10)
81 #define TSL2563_TIMING_GAIN1 (0x00)
83 #define TSL2563_INT_DISBLED (0x00)
84 #define TSL2563_INT_LEVEL (0x10)
85 #define TSL2563_INT_PERSIST(n) ((n) & 0x0F)
87 struct tsl2563_gainlevel_coeff {
93 static struct tsl2563_gainlevel_coeff tsl2563_gainlevel_table[] = {
95 .gaintime = TSL2563_TIMING_400MS | TSL2563_TIMING_GAIN16,
99 .gaintime = TSL2563_TIMING_400MS | TSL2563_TIMING_GAIN1,
103 .gaintime = TSL2563_TIMING_100MS | TSL2563_TIMING_GAIN1,
107 .gaintime = TSL2563_TIMING_13MS | TSL2563_TIMING_GAIN1,
113 struct tsl2563_chip {
115 struct i2c_client *client;
116 struct iio_dev *indio_dev;
117 struct delayed_work poweroff_work;
119 /* Remember state for suspend and resume functions */
122 struct tsl2563_gainlevel_coeff *gainlevel;
124 /* Thresholds are in lux */
129 /* Calibration coefficients */
134 /* Cache current values, to be returned while suspended */
139 static int tsl2563_write(struct i2c_client *client, u8 reg, u8 value)
144 buf[0] = TSL2563_CMD | reg;
147 ret = i2c_master_send(client, buf, sizeof(buf));
148 return (ret == sizeof(buf)) ? 0 : ret;
151 static int tsl2563_read(struct i2c_client *client, u8 reg, void *buf, int len)
154 u8 cmd = TSL2563_CMD | reg;
156 ret = i2c_master_send(client, &cmd, sizeof(cmd));
157 if (ret != sizeof(cmd))
160 return i2c_master_recv(client, buf, len);
163 static int tsl2563_set_power(struct tsl2563_chip *chip, int on)
165 struct i2c_client *client = chip->client;
168 cmd = on ? TSL2563_CMD_POWER_ON : TSL2563_CMD_POWER_OFF;
169 return tsl2563_write(client, TSL2563_REG_CTRL, cmd);
173 * Return value is 0 for off, 1 for on, or a negative error
174 * code if reading failed.
176 static int tsl2563_get_power(struct tsl2563_chip *chip)
178 struct i2c_client *client = chip->client;
182 ret = tsl2563_read(client, TSL2563_REG_CTRL, &val, sizeof(val));
183 if (ret != sizeof(val))
186 return (val & TSL2563_CTRL_POWER_MASK) == TSL2563_CMD_POWER_ON;
189 static int tsl2563_configure(struct tsl2563_chip *chip)
191 struct i2c_client *client = chip->client;
194 ret = tsl2563_write(client, TSL2563_REG_TIMING,
195 chip->gainlevel->gaintime);
199 ret = tsl2563_write(client, TSL2563_REG_INT, chip->intr);
205 static void tsl2563_poweroff_work(struct work_struct *work)
207 struct tsl2563_chip *chip =
208 container_of(work, struct tsl2563_chip, poweroff_work.work);
209 tsl2563_set_power(chip, 0);
212 static int tsl2563_detect(struct tsl2563_chip *chip)
216 ret = tsl2563_set_power(chip, 1);
220 ret = tsl2563_get_power(chip);
224 return ret ? 0 : -ENODEV;
227 static int tsl2563_read_id(struct tsl2563_chip *chip, u8 *id)
229 struct i2c_client *client = chip->client;
232 ret = tsl2563_read(client, TSL2563_REG_ID, id, sizeof(*id));
233 if (ret != sizeof(*id))
240 * "Normalized" ADC value is one obtained with 400ms of integration time and
241 * 16x gain. This function returns the number of bits of shift needed to
242 * convert between normalized values and HW values obtained using given
243 * timing and gain settings.
245 static int adc_shiftbits(u8 timing)
249 switch (timing & TSL2563_TIMING_MASK) {
250 case TSL2563_TIMING_13MS:
253 case TSL2563_TIMING_100MS:
256 case TSL2563_TIMING_400MS:
261 if (!(timing & TSL2563_TIMING_GAIN16))
267 /* Convert a HW ADC value to normalized scale. */
268 static u32 normalize_adc(u16 adc, u8 timing)
270 return adc << adc_shiftbits(timing);
273 static void tsl2563_wait_adc(struct tsl2563_chip *chip)
277 switch (chip->gainlevel->gaintime & TSL2563_TIMING_MASK) {
278 case TSL2563_TIMING_13MS:
281 case TSL2563_TIMING_100MS:
288 * TODO: Make sure that we wait at least required delay but why we
289 * have to extend it one tick more?
291 schedule_timeout_interruptible(msecs_to_jiffies(delay) + 2);
294 static int tsl2563_adjust_gainlevel(struct tsl2563_chip *chip, u16 adc)
296 struct i2c_client *client = chip->client;
298 if (adc > chip->gainlevel->max || adc < chip->gainlevel->min) {
300 (adc > chip->gainlevel->max) ?
301 chip->gainlevel++ : chip->gainlevel--;
303 tsl2563_write(client, TSL2563_REG_TIMING,
304 chip->gainlevel->gaintime);
306 tsl2563_wait_adc(chip);
307 tsl2563_wait_adc(chip);
314 static int tsl2563_get_adc(struct tsl2563_chip *chip)
316 struct i2c_client *client = chip->client;
322 if (chip->state.event != PM_EVENT_ON)
325 cancel_delayed_work(&chip->poweroff_work);
327 if (!tsl2563_get_power(chip)) {
328 ret = tsl2563_set_power(chip, 1);
331 ret = tsl2563_configure(chip);
334 tsl2563_wait_adc(chip);
338 ret = tsl2563_read(client,
339 TSL2563_REG_DATA0LOW | TSL2563_CLEARINT,
341 if (ret != sizeof(buf0))
344 ret = tsl2563_read(client, TSL2563_REG_DATA1LOW,
346 if (ret != sizeof(buf1))
349 adc0 = (buf0[1] << 8) + buf0[0];
350 adc1 = (buf1[1] << 8) + buf1[0];
352 retry = tsl2563_adjust_gainlevel(chip, adc0);
355 chip->data0 = normalize_adc(adc0, chip->gainlevel->gaintime);
356 chip->data1 = normalize_adc(adc1, chip->gainlevel->gaintime);
358 schedule_delayed_work(&chip->poweroff_work, 5 * HZ);
365 static inline int calib_to_sysfs(u32 calib)
367 return (int) (((calib * CALIB_BASE_SYSFS) +
368 CALIB_FRAC_HALF) >> CALIB_FRAC_BITS);
371 static inline u32 calib_from_sysfs(int value)
373 return (((u32) value) << CALIB_FRAC_BITS) / CALIB_BASE_SYSFS;
377 * Conversions between lux and ADC values.
379 * The basic formula is lux = c0 * adc0 - c1 * adc1, where c0 and c1 are
380 * appropriate constants. Different constants are needed for different
381 * kinds of light, determined by the ratio adc1/adc0 (basically the ratio
382 * of the intensities in infrared and visible wavelengths). lux_table below
383 * lists the upper threshold of the adc1/adc0 ratio and the corresponding
387 struct tsl2563_lux_coeff {
388 unsigned long ch_ratio;
389 unsigned long ch0_coeff;
390 unsigned long ch1_coeff;
393 static const struct tsl2563_lux_coeff lux_table[] = {
395 .ch_ratio = FRAC10K(1300),
396 .ch0_coeff = FRAC10K(315),
397 .ch1_coeff = FRAC10K(262),
399 .ch_ratio = FRAC10K(2600),
400 .ch0_coeff = FRAC10K(337),
401 .ch1_coeff = FRAC10K(430),
403 .ch_ratio = FRAC10K(3900),
404 .ch0_coeff = FRAC10K(363),
405 .ch1_coeff = FRAC10K(529),
407 .ch_ratio = FRAC10K(5200),
408 .ch0_coeff = FRAC10K(392),
409 .ch1_coeff = FRAC10K(605),
411 .ch_ratio = FRAC10K(6500),
412 .ch0_coeff = FRAC10K(229),
413 .ch1_coeff = FRAC10K(291),
415 .ch_ratio = FRAC10K(8000),
416 .ch0_coeff = FRAC10K(157),
417 .ch1_coeff = FRAC10K(180),
419 .ch_ratio = FRAC10K(13000),
420 .ch0_coeff = FRAC10K(34),
421 .ch1_coeff = FRAC10K(26),
423 .ch_ratio = ULONG_MAX,
430 * Convert normalized, scaled ADC values to lux.
432 static unsigned int adc_to_lux(u32 adc0, u32 adc1)
434 const struct tsl2563_lux_coeff *lp = lux_table;
435 unsigned long ratio, lux, ch0 = adc0, ch1 = adc1;
437 ratio = ch0 ? ((ch1 << ADC_FRAC_BITS) / ch0) : ULONG_MAX;
439 while (lp->ch_ratio < ratio)
442 lux = ch0 * lp->ch0_coeff - ch1 * lp->ch1_coeff;
444 return (unsigned int) (lux >> ADC_FRAC_BITS);
447 /*--------------------------------------------------------------*/
448 /* Sysfs interface */
449 /*--------------------------------------------------------------*/
451 static ssize_t tsl2563_adc0_show(struct device *dev,
452 struct device_attribute *attr, char *buf)
454 struct iio_dev *indio_dev = dev_get_drvdata(dev);
455 struct tsl2563_chip *chip = indio_dev->dev_data;
458 mutex_lock(&chip->lock);
460 ret = tsl2563_get_adc(chip);
464 ret = snprintf(buf, PAGE_SIZE, "%d\n", chip->data0);
466 mutex_unlock(&chip->lock);
470 static ssize_t tsl2563_adc1_show(struct device *dev,
471 struct device_attribute *attr, char *buf)
473 struct iio_dev *indio_dev = dev_get_drvdata(dev);
474 struct tsl2563_chip *chip = indio_dev->dev_data;
477 mutex_lock(&chip->lock);
479 ret = tsl2563_get_adc(chip);
483 ret = snprintf(buf, PAGE_SIZE, "%d\n", chip->data1);
485 mutex_unlock(&chip->lock);
489 /* Apply calibration coefficient to ADC count. */
490 static u32 calib_adc(u32 adc, u32 calib)
492 unsigned long scaled = adc;
495 scaled >>= CALIB_FRAC_BITS;
500 static ssize_t tsl2563_lux_show(struct device *dev,
501 struct device_attribute *attr, char *buf)
503 struct iio_dev *indio_dev = dev_get_drvdata(dev);
504 struct tsl2563_chip *chip = indio_dev->dev_data;
508 mutex_lock(&chip->lock);
510 ret = tsl2563_get_adc(chip);
514 calib0 = calib_adc(chip->data0, chip->calib0) * chip->cover_comp_gain;
515 calib1 = calib_adc(chip->data1, chip->calib1) * chip->cover_comp_gain;
517 ret = snprintf(buf, PAGE_SIZE, "%d\n", adc_to_lux(calib0, calib1));
520 mutex_unlock(&chip->lock);
524 static ssize_t format_calib(char *buf, int len, u32 calib)
526 return snprintf(buf, PAGE_SIZE, "%d\n", calib_to_sysfs(calib));
529 static ssize_t tsl2563_calib0_show(struct device *dev,
530 struct device_attribute *attr, char *buf)
532 struct iio_dev *indio_dev = dev_get_drvdata(dev);
533 struct tsl2563_chip *chip = indio_dev->dev_data;
536 mutex_lock(&chip->lock);
537 ret = format_calib(buf, PAGE_SIZE, chip->calib0);
538 mutex_unlock(&chip->lock);
542 static ssize_t tsl2563_calib1_show(struct device *dev,
543 struct device_attribute *attr, char *buf)
545 struct iio_dev *indio_dev = dev_get_drvdata(dev);
546 struct tsl2563_chip *chip = indio_dev->dev_data;
549 mutex_lock(&chip->lock);
550 ret = format_calib(buf, PAGE_SIZE, chip->calib1);
551 mutex_unlock(&chip->lock);
555 static int do_calib_store(struct device *dev, const char *buf, size_t len,
558 struct iio_dev *indio_dev = dev_get_drvdata(dev);
559 struct tsl2563_chip *chip = indio_dev->dev_data;
563 if (1 != sscanf(buf, "%d", &value))
566 calib = calib_from_sysfs(value);
569 chip->calib1 = calib;
571 chip->calib0 = calib;
576 static ssize_t tsl2563_calib0_store(struct device *dev,
577 struct device_attribute *attr,
578 const char *buf, size_t len)
580 return do_calib_store(dev, buf, len, 0);
583 static ssize_t tsl2563_calib1_store(struct device *dev,
584 struct device_attribute *attr,
585 const char *buf, size_t len)
587 return do_calib_store(dev, buf, len, 1);
590 /* AmitXXXX: Convert to IIO_DEV_ATTR_LIGHT* as in tsl2561
591 * once I understand what they mean */
592 static DEVICE_ATTR(adc0, S_IRUGO, tsl2563_adc0_show, NULL);
593 static DEVICE_ATTR(adc1, S_IRUGO, tsl2563_adc1_show, NULL);
594 static DEVICE_ATTR(lux, S_IRUGO, tsl2563_lux_show, NULL);
595 static DEVICE_ATTR(calib0, S_IRUGO | S_IWUSR,
596 tsl2563_calib0_show, tsl2563_calib0_store);
597 static DEVICE_ATTR(calib1, S_IRUGO | S_IWUSR,
598 tsl2563_calib1_show, tsl2563_calib1_store);
600 static struct attribute *tsl2563_attributes[] = {
604 &dev_attr_calib0.attr,
605 &dev_attr_calib1.attr,
609 static const struct attribute_group tsl2563_group = {
610 .attrs = tsl2563_attributes,
613 /*--------------------------------------------------------------*/
614 /* Probe, Attach, Remove */
615 /*--------------------------------------------------------------*/
616 static struct i2c_driver tsl2563_i2c_driver;
618 static int __devinit tsl2563_probe(struct i2c_client *client,
619 const struct i2c_device_id *device_id)
621 struct tsl2563_chip *chip;
622 struct tsl2563_platform_data *pdata = client->dev.platform_data;
627 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
631 i2c_set_clientdata(client, chip);
632 chip->client = client;
634 err = tsl2563_detect(chip);
636 dev_err(&client->dev, "device not found, error %d \n", -err);
640 err = tsl2563_read_id(chip, &id);
644 mutex_init(&chip->lock);
646 /* Default values used until userspace says otherwise */
647 chip->low_thres = 0x0;
648 chip->high_thres = 0xffff;
649 chip->gainlevel = tsl2563_gainlevel_table;
650 chip->intr = TSL2563_INT_PERSIST(4);
651 chip->calib0 = calib_from_sysfs(CALIB_BASE_SYSFS);
652 chip->calib1 = calib_from_sysfs(CALIB_BASE_SYSFS);
655 chip->cover_comp_gain = pdata->cover_comp_gain;
657 chip->cover_comp_gain = 1;
659 dev_info(&client->dev, "model %d, rev. %d\n", id >> 4, id & 0x0f);
661 chip->indio_dev = iio_allocate_device();
662 if (!chip->indio_dev)
664 chip->indio_dev->attrs = &tsl2563_group;
665 chip->indio_dev->dev.parent = &client->dev;
666 chip->indio_dev->dev_data = (void *)(chip);
667 chip->indio_dev->driver_module = THIS_MODULE;
668 chip->indio_dev->modes = INDIO_DIRECT_MODE;
669 ret = iio_device_register(chip->indio_dev);
673 err = tsl2563_configure(chip);
677 INIT_DELAYED_WORK(&chip->poweroff_work, tsl2563_poweroff_work);
678 schedule_delayed_work(&chip->poweroff_work, 5 * HZ);
682 iio_device_unregister(chip->indio_dev);
688 static int tsl2563_remove(struct i2c_client *client)
690 struct tsl2563_chip *chip = i2c_get_clientdata(client);
692 iio_device_unregister(chip->indio_dev);
698 static int tsl2563_suspend(struct i2c_client *client, pm_message_t state)
700 struct tsl2563_chip *chip = i2c_get_clientdata(client);
703 mutex_lock(&chip->lock);
705 ret = tsl2563_set_power(chip, 0);
712 mutex_unlock(&chip->lock);
716 static int tsl2563_resume(struct i2c_client *client)
718 struct tsl2563_chip *chip = i2c_get_clientdata(client);
721 mutex_lock(&chip->lock);
723 ret = tsl2563_set_power(chip, 1);
727 ret = tsl2563_configure(chip);
731 chip->state.event = PM_EVENT_ON;
734 mutex_unlock(&chip->lock);
738 static const struct i2c_device_id tsl2563_id[] = {
745 MODULE_DEVICE_TABLE(i2c, tsl2563_id);
747 static struct i2c_driver tsl2563_i2c_driver = {
751 .suspend = tsl2563_suspend,
752 .resume = tsl2563_resume,
753 .probe = tsl2563_probe,
754 .remove = __devexit_p(tsl2563_remove),
755 .id_table = tsl2563_id,
758 static int __init tsl2563_init(void)
760 return i2c_add_driver(&tsl2563_i2c_driver);
763 static void __exit tsl2563_exit(void)
765 i2c_del_driver(&tsl2563_i2c_driver);
768 MODULE_AUTHOR("Nokia Corporation");
769 MODULE_DESCRIPTION("tsl2563 light sensor driver");
770 MODULE_LICENSE("GPL");
772 module_init(tsl2563_init);
773 module_exit(tsl2563_exit);