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>
37 #include <linux/slab.h>
42 /* Use this many bits for fraction part. */
43 #define ADC_FRAC_BITS (14)
45 /* Given number of 1/10000's in ADC_FRAC_BITS precision. */
46 #define FRAC10K(f) (((f) * (1L << (ADC_FRAC_BITS))) / (10000))
48 /* Bits used for fraction in calibration coefficients.*/
49 #define CALIB_FRAC_BITS (10)
50 /* 0.5 in CALIB_FRAC_BITS precision */
51 #define CALIB_FRAC_HALF (1 << (CALIB_FRAC_BITS - 1))
52 /* Make a fraction from a number n that was multiplied with b. */
53 #define CALIB_FRAC(n, b) (((n) << CALIB_FRAC_BITS) / (b))
54 /* Decimal 10^(digits in sysfs presentation) */
55 #define CALIB_BASE_SYSFS (1000)
57 #define TSL2563_CMD (0x80)
58 #define TSL2563_CLEARINT (0x40)
60 #define TSL2563_REG_CTRL (0x00)
61 #define TSL2563_REG_TIMING (0x01)
62 #define TSL2563_REG_LOWLOW (0x02) /* data0 low threshold, 2 bytes */
63 #define TSL2563_REG_LOWHIGH (0x03)
64 #define TSL2563_REG_HIGHLOW (0x04) /* data0 high threshold, 2 bytes */
65 #define TSL2563_REG_HIGHHIGH (0x05)
66 #define TSL2563_REG_INT (0x06)
67 #define TSL2563_REG_ID (0x0a)
68 #define TSL2563_REG_DATA0LOW (0x0c) /* broadband sensor value, 2 bytes */
69 #define TSL2563_REG_DATA0HIGH (0x0d)
70 #define TSL2563_REG_DATA1LOW (0x0e) /* infrared sensor value, 2 bytes */
71 #define TSL2563_REG_DATA1HIGH (0x0f)
73 #define TSL2563_CMD_POWER_ON (0x03)
74 #define TSL2563_CMD_POWER_OFF (0x00)
75 #define TSL2563_CTRL_POWER_MASK (0x03)
77 #define TSL2563_TIMING_13MS (0x00)
78 #define TSL2563_TIMING_100MS (0x01)
79 #define TSL2563_TIMING_400MS (0x02)
80 #define TSL2563_TIMING_MASK (0x03)
81 #define TSL2563_TIMING_GAIN16 (0x10)
82 #define TSL2563_TIMING_GAIN1 (0x00)
84 #define TSL2563_INT_DISBLED (0x00)
85 #define TSL2563_INT_LEVEL (0x10)
86 #define TSL2563_INT_PERSIST(n) ((n) & 0x0F)
88 struct tsl2563_gainlevel_coeff
{
94 static struct tsl2563_gainlevel_coeff tsl2563_gainlevel_table
[] = {
96 .gaintime
= TSL2563_TIMING_400MS
| TSL2563_TIMING_GAIN16
,
100 .gaintime
= TSL2563_TIMING_400MS
| TSL2563_TIMING_GAIN1
,
104 .gaintime
= TSL2563_TIMING_100MS
| TSL2563_TIMING_GAIN1
,
108 .gaintime
= TSL2563_TIMING_13MS
| TSL2563_TIMING_GAIN1
,
114 struct tsl2563_chip
{
116 struct i2c_client
*client
;
117 struct iio_dev
*indio_dev
;
118 struct delayed_work poweroff_work
;
120 /* Remember state for suspend and resume functions */
123 struct tsl2563_gainlevel_coeff
*gainlevel
;
125 /* Thresholds are in lux */
130 /* Calibration coefficients */
135 /* Cache current values, to be returned while suspended */
140 static int tsl2563_write(struct i2c_client
*client
, u8 reg
, u8 value
)
145 buf
[0] = TSL2563_CMD
| reg
;
148 ret
= i2c_master_send(client
, buf
, sizeof(buf
));
149 return (ret
== sizeof(buf
)) ? 0 : ret
;
152 static int tsl2563_read(struct i2c_client
*client
, u8 reg
, void *buf
, int len
)
155 u8 cmd
= TSL2563_CMD
| reg
;
157 ret
= i2c_master_send(client
, &cmd
, sizeof(cmd
));
158 if (ret
!= sizeof(cmd
))
161 return i2c_master_recv(client
, buf
, len
);
164 static int tsl2563_set_power(struct tsl2563_chip
*chip
, int on
)
166 struct i2c_client
*client
= chip
->client
;
169 cmd
= on
? TSL2563_CMD_POWER_ON
: TSL2563_CMD_POWER_OFF
;
170 return tsl2563_write(client
, TSL2563_REG_CTRL
, cmd
);
174 * Return value is 0 for off, 1 for on, or a negative error
175 * code if reading failed.
177 static int tsl2563_get_power(struct tsl2563_chip
*chip
)
179 struct i2c_client
*client
= chip
->client
;
183 ret
= tsl2563_read(client
, TSL2563_REG_CTRL
, &val
, sizeof(val
));
184 if (ret
!= sizeof(val
))
187 return (val
& TSL2563_CTRL_POWER_MASK
) == TSL2563_CMD_POWER_ON
;
190 static int tsl2563_configure(struct tsl2563_chip
*chip
)
192 struct i2c_client
*client
= chip
->client
;
195 ret
= tsl2563_write(client
, TSL2563_REG_TIMING
,
196 chip
->gainlevel
->gaintime
);
200 ret
= tsl2563_write(client
, TSL2563_REG_INT
, chip
->intr
);
206 static void tsl2563_poweroff_work(struct work_struct
*work
)
208 struct tsl2563_chip
*chip
=
209 container_of(work
, struct tsl2563_chip
, poweroff_work
.work
);
210 tsl2563_set_power(chip
, 0);
213 static int tsl2563_detect(struct tsl2563_chip
*chip
)
217 ret
= tsl2563_set_power(chip
, 1);
221 ret
= tsl2563_get_power(chip
);
225 return ret
? 0 : -ENODEV
;
228 static int tsl2563_read_id(struct tsl2563_chip
*chip
, u8
*id
)
230 struct i2c_client
*client
= chip
->client
;
233 ret
= tsl2563_read(client
, TSL2563_REG_ID
, id
, sizeof(*id
));
234 if (ret
!= sizeof(*id
))
241 * "Normalized" ADC value is one obtained with 400ms of integration time and
242 * 16x gain. This function returns the number of bits of shift needed to
243 * convert between normalized values and HW values obtained using given
244 * timing and gain settings.
246 static int adc_shiftbits(u8 timing
)
250 switch (timing
& TSL2563_TIMING_MASK
) {
251 case TSL2563_TIMING_13MS
:
254 case TSL2563_TIMING_100MS
:
257 case TSL2563_TIMING_400MS
:
262 if (!(timing
& TSL2563_TIMING_GAIN16
))
268 /* Convert a HW ADC value to normalized scale. */
269 static u32
normalize_adc(u16 adc
, u8 timing
)
271 return adc
<< adc_shiftbits(timing
);
274 static void tsl2563_wait_adc(struct tsl2563_chip
*chip
)
278 switch (chip
->gainlevel
->gaintime
& TSL2563_TIMING_MASK
) {
279 case TSL2563_TIMING_13MS
:
282 case TSL2563_TIMING_100MS
:
289 * TODO: Make sure that we wait at least required delay but why we
290 * have to extend it one tick more?
292 schedule_timeout_interruptible(msecs_to_jiffies(delay
) + 2);
295 static int tsl2563_adjust_gainlevel(struct tsl2563_chip
*chip
, u16 adc
)
297 struct i2c_client
*client
= chip
->client
;
299 if (adc
> chip
->gainlevel
->max
|| adc
< chip
->gainlevel
->min
) {
301 (adc
> chip
->gainlevel
->max
) ?
302 chip
->gainlevel
++ : chip
->gainlevel
--;
304 tsl2563_write(client
, TSL2563_REG_TIMING
,
305 chip
->gainlevel
->gaintime
);
307 tsl2563_wait_adc(chip
);
308 tsl2563_wait_adc(chip
);
315 static int tsl2563_get_adc(struct tsl2563_chip
*chip
)
317 struct i2c_client
*client
= chip
->client
;
323 if (chip
->state
.event
!= PM_EVENT_ON
)
326 cancel_delayed_work(&chip
->poweroff_work
);
328 if (!tsl2563_get_power(chip
)) {
329 ret
= tsl2563_set_power(chip
, 1);
332 ret
= tsl2563_configure(chip
);
335 tsl2563_wait_adc(chip
);
339 ret
= tsl2563_read(client
,
340 TSL2563_REG_DATA0LOW
| TSL2563_CLEARINT
,
342 if (ret
!= sizeof(buf0
))
345 ret
= tsl2563_read(client
, TSL2563_REG_DATA1LOW
,
347 if (ret
!= sizeof(buf1
))
350 adc0
= (buf0
[1] << 8) + buf0
[0];
351 adc1
= (buf1
[1] << 8) + buf1
[0];
353 retry
= tsl2563_adjust_gainlevel(chip
, adc0
);
356 chip
->data0
= normalize_adc(adc0
, chip
->gainlevel
->gaintime
);
357 chip
->data1
= normalize_adc(adc1
, chip
->gainlevel
->gaintime
);
359 schedule_delayed_work(&chip
->poweroff_work
, 5 * HZ
);
366 static inline int calib_to_sysfs(u32 calib
)
368 return (int) (((calib
* CALIB_BASE_SYSFS
) +
369 CALIB_FRAC_HALF
) >> CALIB_FRAC_BITS
);
372 static inline u32
calib_from_sysfs(int value
)
374 return (((u32
) value
) << CALIB_FRAC_BITS
) / CALIB_BASE_SYSFS
;
378 * Conversions between lux and ADC values.
380 * The basic formula is lux = c0 * adc0 - c1 * adc1, where c0 and c1 are
381 * appropriate constants. Different constants are needed for different
382 * kinds of light, determined by the ratio adc1/adc0 (basically the ratio
383 * of the intensities in infrared and visible wavelengths). lux_table below
384 * lists the upper threshold of the adc1/adc0 ratio and the corresponding
388 struct tsl2563_lux_coeff
{
389 unsigned long ch_ratio
;
390 unsigned long ch0_coeff
;
391 unsigned long ch1_coeff
;
394 static const struct tsl2563_lux_coeff lux_table
[] = {
396 .ch_ratio
= FRAC10K(1300),
397 .ch0_coeff
= FRAC10K(315),
398 .ch1_coeff
= FRAC10K(262),
400 .ch_ratio
= FRAC10K(2600),
401 .ch0_coeff
= FRAC10K(337),
402 .ch1_coeff
= FRAC10K(430),
404 .ch_ratio
= FRAC10K(3900),
405 .ch0_coeff
= FRAC10K(363),
406 .ch1_coeff
= FRAC10K(529),
408 .ch_ratio
= FRAC10K(5200),
409 .ch0_coeff
= FRAC10K(392),
410 .ch1_coeff
= FRAC10K(605),
412 .ch_ratio
= FRAC10K(6500),
413 .ch0_coeff
= FRAC10K(229),
414 .ch1_coeff
= FRAC10K(291),
416 .ch_ratio
= FRAC10K(8000),
417 .ch0_coeff
= FRAC10K(157),
418 .ch1_coeff
= FRAC10K(180),
420 .ch_ratio
= FRAC10K(13000),
421 .ch0_coeff
= FRAC10K(34),
422 .ch1_coeff
= FRAC10K(26),
424 .ch_ratio
= ULONG_MAX
,
431 * Convert normalized, scaled ADC values to lux.
433 static unsigned int adc_to_lux(u32 adc0
, u32 adc1
)
435 const struct tsl2563_lux_coeff
*lp
= lux_table
;
436 unsigned long ratio
, lux
, ch0
= adc0
, ch1
= adc1
;
438 ratio
= ch0
? ((ch1
<< ADC_FRAC_BITS
) / ch0
) : ULONG_MAX
;
440 while (lp
->ch_ratio
< ratio
)
443 lux
= ch0
* lp
->ch0_coeff
- ch1
* lp
->ch1_coeff
;
445 return (unsigned int) (lux
>> ADC_FRAC_BITS
);
448 /*--------------------------------------------------------------*/
449 /* Sysfs interface */
450 /*--------------------------------------------------------------*/
452 static ssize_t
tsl2563_adc0_show(struct device
*dev
,
453 struct device_attribute
*attr
, char *buf
)
455 struct iio_dev
*indio_dev
= dev_get_drvdata(dev
);
456 struct tsl2563_chip
*chip
= indio_dev
->dev_data
;
459 mutex_lock(&chip
->lock
);
461 ret
= tsl2563_get_adc(chip
);
465 ret
= snprintf(buf
, PAGE_SIZE
, "%d\n", chip
->data0
);
467 mutex_unlock(&chip
->lock
);
471 static ssize_t
tsl2563_adc1_show(struct device
*dev
,
472 struct device_attribute
*attr
, char *buf
)
474 struct iio_dev
*indio_dev
= dev_get_drvdata(dev
);
475 struct tsl2563_chip
*chip
= indio_dev
->dev_data
;
478 mutex_lock(&chip
->lock
);
480 ret
= tsl2563_get_adc(chip
);
484 ret
= snprintf(buf
, PAGE_SIZE
, "%d\n", chip
->data1
);
486 mutex_unlock(&chip
->lock
);
490 /* Apply calibration coefficient to ADC count. */
491 static u32
calib_adc(u32 adc
, u32 calib
)
493 unsigned long scaled
= adc
;
496 scaled
>>= CALIB_FRAC_BITS
;
501 static ssize_t
tsl2563_lux_show(struct device
*dev
,
502 struct device_attribute
*attr
, char *buf
)
504 struct iio_dev
*indio_dev
= dev_get_drvdata(dev
);
505 struct tsl2563_chip
*chip
= indio_dev
->dev_data
;
509 mutex_lock(&chip
->lock
);
511 ret
= tsl2563_get_adc(chip
);
515 calib0
= calib_adc(chip
->data0
, chip
->calib0
) * chip
->cover_comp_gain
;
516 calib1
= calib_adc(chip
->data1
, chip
->calib1
) * chip
->cover_comp_gain
;
518 ret
= snprintf(buf
, PAGE_SIZE
, "%d\n", adc_to_lux(calib0
, calib1
));
521 mutex_unlock(&chip
->lock
);
525 static ssize_t
format_calib(char *buf
, int len
, u32 calib
)
527 return snprintf(buf
, PAGE_SIZE
, "%d\n", calib_to_sysfs(calib
));
530 static ssize_t
tsl2563_calib0_show(struct device
*dev
,
531 struct device_attribute
*attr
, char *buf
)
533 struct iio_dev
*indio_dev
= dev_get_drvdata(dev
);
534 struct tsl2563_chip
*chip
= indio_dev
->dev_data
;
537 mutex_lock(&chip
->lock
);
538 ret
= format_calib(buf
, PAGE_SIZE
, chip
->calib0
);
539 mutex_unlock(&chip
->lock
);
543 static ssize_t
tsl2563_calib1_show(struct device
*dev
,
544 struct device_attribute
*attr
, char *buf
)
546 struct iio_dev
*indio_dev
= dev_get_drvdata(dev
);
547 struct tsl2563_chip
*chip
= indio_dev
->dev_data
;
550 mutex_lock(&chip
->lock
);
551 ret
= format_calib(buf
, PAGE_SIZE
, chip
->calib1
);
552 mutex_unlock(&chip
->lock
);
556 static int do_calib_store(struct device
*dev
, const char *buf
, size_t len
,
559 struct iio_dev
*indio_dev
= dev_get_drvdata(dev
);
560 struct tsl2563_chip
*chip
= indio_dev
->dev_data
;
564 if (1 != sscanf(buf
, "%d", &value
))
567 calib
= calib_from_sysfs(value
);
570 chip
->calib1
= calib
;
572 chip
->calib0
= calib
;
577 static ssize_t
tsl2563_calib0_store(struct device
*dev
,
578 struct device_attribute
*attr
,
579 const char *buf
, size_t len
)
581 return do_calib_store(dev
, buf
, len
, 0);
584 static ssize_t
tsl2563_calib1_store(struct device
*dev
,
585 struct device_attribute
*attr
,
586 const char *buf
, size_t len
)
588 return do_calib_store(dev
, buf
, len
, 1);
591 /* AmitXXXX: Convert to IIO_DEV_ATTR_LIGHT* as in tsl2561
592 * once I understand what they mean */
593 static DEVICE_ATTR(adc0
, S_IRUGO
, tsl2563_adc0_show
, NULL
);
594 static DEVICE_ATTR(adc1
, S_IRUGO
, tsl2563_adc1_show
, NULL
);
595 static DEVICE_ATTR(lux
, S_IRUGO
, tsl2563_lux_show
, NULL
);
596 static DEVICE_ATTR(calib0
, S_IRUGO
| S_IWUSR
,
597 tsl2563_calib0_show
, tsl2563_calib0_store
);
598 static DEVICE_ATTR(calib1
, S_IRUGO
| S_IWUSR
,
599 tsl2563_calib1_show
, tsl2563_calib1_store
);
601 static struct attribute
*tsl2563_attributes
[] = {
605 &dev_attr_calib0
.attr
,
606 &dev_attr_calib1
.attr
,
610 static const struct attribute_group tsl2563_group
= {
611 .attrs
= tsl2563_attributes
,
614 /*--------------------------------------------------------------*/
615 /* Probe, Attach, Remove */
616 /*--------------------------------------------------------------*/
617 static struct i2c_driver tsl2563_i2c_driver
;
619 static int __devinit
tsl2563_probe(struct i2c_client
*client
,
620 const struct i2c_device_id
*device_id
)
622 struct tsl2563_chip
*chip
;
623 struct tsl2563_platform_data
*pdata
= client
->dev
.platform_data
;
628 chip
= kzalloc(sizeof(*chip
), GFP_KERNEL
);
632 i2c_set_clientdata(client
, chip
);
633 chip
->client
= client
;
635 err
= tsl2563_detect(chip
);
637 dev_err(&client
->dev
, "device not found, error %d \n", -err
);
641 err
= tsl2563_read_id(chip
, &id
);
645 mutex_init(&chip
->lock
);
647 /* Default values used until userspace says otherwise */
648 chip
->low_thres
= 0x0;
649 chip
->high_thres
= 0xffff;
650 chip
->gainlevel
= tsl2563_gainlevel_table
;
651 chip
->intr
= TSL2563_INT_PERSIST(4);
652 chip
->calib0
= calib_from_sysfs(CALIB_BASE_SYSFS
);
653 chip
->calib1
= calib_from_sysfs(CALIB_BASE_SYSFS
);
656 chip
->cover_comp_gain
= pdata
->cover_comp_gain
;
658 chip
->cover_comp_gain
= 1;
660 dev_info(&client
->dev
, "model %d, rev. %d\n", id
>> 4, id
& 0x0f);
662 chip
->indio_dev
= iio_allocate_device();
663 if (!chip
->indio_dev
)
665 chip
->indio_dev
->attrs
= &tsl2563_group
;
666 chip
->indio_dev
->dev
.parent
= &client
->dev
;
667 chip
->indio_dev
->dev_data
= (void *)(chip
);
668 chip
->indio_dev
->driver_module
= THIS_MODULE
;
669 chip
->indio_dev
->modes
= INDIO_DIRECT_MODE
;
670 ret
= iio_device_register(chip
->indio_dev
);
674 err
= tsl2563_configure(chip
);
678 INIT_DELAYED_WORK(&chip
->poweroff_work
, tsl2563_poweroff_work
);
679 schedule_delayed_work(&chip
->poweroff_work
, 5 * HZ
);
683 iio_device_unregister(chip
->indio_dev
);
689 static int tsl2563_remove(struct i2c_client
*client
)
691 struct tsl2563_chip
*chip
= i2c_get_clientdata(client
);
693 iio_device_unregister(chip
->indio_dev
);
699 static int tsl2563_suspend(struct i2c_client
*client
, pm_message_t state
)
701 struct tsl2563_chip
*chip
= i2c_get_clientdata(client
);
704 mutex_lock(&chip
->lock
);
706 ret
= tsl2563_set_power(chip
, 0);
713 mutex_unlock(&chip
->lock
);
717 static int tsl2563_resume(struct i2c_client
*client
)
719 struct tsl2563_chip
*chip
= i2c_get_clientdata(client
);
722 mutex_lock(&chip
->lock
);
724 ret
= tsl2563_set_power(chip
, 1);
728 ret
= tsl2563_configure(chip
);
732 chip
->state
.event
= PM_EVENT_ON
;
735 mutex_unlock(&chip
->lock
);
739 static const struct i2c_device_id tsl2563_id
[] = {
746 MODULE_DEVICE_TABLE(i2c
, tsl2563_id
);
748 static struct i2c_driver tsl2563_i2c_driver
= {
752 .suspend
= tsl2563_suspend
,
753 .resume
= tsl2563_resume
,
754 .probe
= tsl2563_probe
,
755 .remove
= __devexit_p(tsl2563_remove
),
756 .id_table
= tsl2563_id
,
759 static int __init
tsl2563_init(void)
761 return i2c_add_driver(&tsl2563_i2c_driver
);
764 static void __exit
tsl2563_exit(void)
766 i2c_del_driver(&tsl2563_i2c_driver
);
769 MODULE_AUTHOR("Nokia Corporation");
770 MODULE_DESCRIPTION("tsl2563 light sensor driver");
771 MODULE_LICENSE("GPL");
773 module_init(tsl2563_init
);
774 module_exit(tsl2563_exit
);