1 /* Copyright (C) 2010 Texas Instruments
2 Author: Shubhrajyoti Datta <shubhrajyoti@ti.com>
3 Acknowledgement: Jonathan Cameron <jic23@kernel.org> for valuable inputs.
5 Support for HMC5883 and HMC5883L by Peter Meerwald <pmeerw@pmeerw.net>.
7 Split to multiple files by Josef Gajdusek <atx@atx.name> - 2014
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU 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., 675 Mass Ave, Cambridge, MA 02139, USA.
24 #include <linux/module.h>
25 #include <linux/regmap.h>
26 #include <linux/iio/iio.h>
27 #include <linux/iio/sysfs.h>
28 #include <linux/iio/trigger_consumer.h>
29 #include <linux/iio/buffer.h>
30 #include <linux/iio/triggered_buffer.h>
31 #include <linux/delay.h>
36 * Range gain settings in (+-)Ga
37 * Beware: HMC5843 and HMC5883 have different recommended sensor field
38 * ranges; default corresponds to +-1.0 Ga and +-1.3 Ga, respectively
40 #define HMC5843_RANGE_GAIN_OFFSET 0x05
41 #define HMC5843_RANGE_GAIN_DEFAULT 0x01
42 #define HMC5843_RANGE_GAIN_MASK 0xe0
45 #define HMC5843_DATA_READY 0x01
46 #define HMC5843_DATA_OUTPUT_LOCK 0x02
48 /* Mode register configuration */
49 #define HMC5843_MODE_CONVERSION_CONTINUOUS 0x00
50 #define HMC5843_MODE_CONVERSION_SINGLE 0x01
51 #define HMC5843_MODE_IDLE 0x02
52 #define HMC5843_MODE_SLEEP 0x03
53 #define HMC5843_MODE_MASK 0x03
56 * HMC5843: Minimum data output rate
57 * HMC5883: Typical data output rate
59 #define HMC5843_RATE_OFFSET 0x02
60 #define HMC5843_RATE_DEFAULT 0x04
61 #define HMC5843_RATE_MASK 0x1c
63 /* Device measurement configuration */
64 #define HMC5843_MEAS_CONF_NORMAL 0x00
65 #define HMC5843_MEAS_CONF_POSITIVE_BIAS 0x01
66 #define HMC5843_MEAS_CONF_NEGATIVE_BIAS 0x02
67 #define HMC5843_MEAS_CONF_MASK 0x03
69 /* Scaling factors: 10000000/Gain */
70 static const int hmc5843_regval_to_nanoscale[] = {
71 6173, 7692, 10309, 12821, 18868, 21739, 25641, 35714
74 static const int hmc5883_regval_to_nanoscale[] = {
75 7812, 9766, 13021, 16287, 24096, 27701, 32573, 45662
78 static const int hmc5883l_regval_to_nanoscale[] = {
79 7299, 9174, 12195, 15152, 22727, 25641, 30303, 43478
84 * Value | HMC5843 | HMC5883/HMC5883L
85 * | Data output rate (Hz) | Data output rate (Hz)
90 * 4 | 10 (default) | 15
93 * 7 | Not used | Not used
95 static const int hmc5843_regval_to_samp_freq[][2] = {
96 {0, 500000}, {1, 0}, {2, 0}, {5, 0}, {10, 0}, {20, 0}, {50, 0}
99 static const int hmc5883_regval_to_samp_freq[][2] = {
100 {0, 750000}, {1, 500000}, {3, 0}, {7, 500000}, {15, 0}, {30, 0},
104 /* Describe chip variants */
105 struct hmc5843_chip_info {
106 const struct iio_chan_spec *channels;
107 const int (*regval_to_samp_freq)[2];
108 const int n_regval_to_samp_freq;
109 const int *regval_to_nanoscale;
110 const int n_regval_to_nanoscale;
113 /* The lower two bits contain the current conversion mode */
114 static s32 hmc5843_set_mode(struct hmc5843_data *data, u8 operating_mode)
118 mutex_lock(&data->lock);
119 ret = regmap_update_bits(data->regmap, HMC5843_MODE_REG,
120 HMC5843_MODE_MASK, operating_mode);
121 mutex_unlock(&data->lock);
126 static int hmc5843_wait_measurement(struct hmc5843_data *data)
132 while (tries-- > 0) {
133 ret = regmap_read(data->regmap, HMC5843_STATUS_REG, &val);
136 if (val & HMC5843_DATA_READY)
142 dev_err(data->dev, "data not ready\n");
149 /* Return the measurement value from the specified channel */
150 static int hmc5843_read_measurement(struct hmc5843_data *data,
156 mutex_lock(&data->lock);
157 ret = hmc5843_wait_measurement(data);
159 mutex_unlock(&data->lock);
162 ret = regmap_bulk_read(data->regmap, HMC5843_DATA_OUT_MSB_REGS,
163 values, sizeof(values));
164 mutex_unlock(&data->lock);
168 *val = sign_extend32(be16_to_cpu(values[idx]), 15);
173 * API for setting the measurement configuration to
174 * Normal, Positive bias and Negative bias
176 * From the datasheet:
177 * 0 - Normal measurement configuration (default): In normal measurement
178 * configuration the device follows normal measurement flow. Pins BP
179 * and BN are left floating and high impedance.
181 * 1 - Positive bias configuration: In positive bias configuration, a
182 * positive current is forced across the resistive load on pins BP
185 * 2 - Negative bias configuration. In negative bias configuration, a
186 * negative current is forced across the resistive load on pins BP
190 static int hmc5843_set_meas_conf(struct hmc5843_data *data, u8 meas_conf)
194 mutex_lock(&data->lock);
195 ret = regmap_update_bits(data->regmap, HMC5843_CONFIG_REG_A,
196 HMC5843_MEAS_CONF_MASK, meas_conf);
197 mutex_unlock(&data->lock);
202 static ssize_t hmc5843_show_measurement_configuration(struct device *dev,
203 struct device_attribute *attr,
206 struct hmc5843_data *data = iio_priv(dev_to_iio_dev(dev));
210 ret = regmap_read(data->regmap, HMC5843_CONFIG_REG_A, &val);
213 val &= HMC5843_MEAS_CONF_MASK;
215 return sprintf(buf, "%d\n", val);
218 static ssize_t hmc5843_set_measurement_configuration(struct device *dev,
219 struct device_attribute *attr,
223 struct hmc5843_data *data = iio_priv(dev_to_iio_dev(dev));
224 unsigned long meas_conf = 0;
227 ret = kstrtoul(buf, 10, &meas_conf);
230 if (meas_conf >= HMC5843_MEAS_CONF_MASK)
233 ret = hmc5843_set_meas_conf(data, meas_conf);
235 return (ret < 0) ? ret : count;
238 static IIO_DEVICE_ATTR(meas_conf,
240 hmc5843_show_measurement_configuration,
241 hmc5843_set_measurement_configuration,
244 static ssize_t hmc5843_show_samp_freq_avail(struct device *dev,
245 struct device_attribute *attr, char *buf)
247 struct hmc5843_data *data = iio_priv(dev_to_iio_dev(dev));
251 for (i = 0; i < data->variant->n_regval_to_samp_freq; i++)
252 len += scnprintf(buf + len, PAGE_SIZE - len,
253 "%d.%d ", data->variant->regval_to_samp_freq[i][0],
254 data->variant->regval_to_samp_freq[i][1]);
256 /* replace trailing space by newline */
262 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(hmc5843_show_samp_freq_avail);
264 static int hmc5843_set_samp_freq(struct hmc5843_data *data, u8 rate)
268 mutex_lock(&data->lock);
269 ret = regmap_update_bits(data->regmap, HMC5843_CONFIG_REG_A,
270 HMC5843_RATE_MASK, rate << HMC5843_RATE_OFFSET);
271 mutex_unlock(&data->lock);
276 static int hmc5843_get_samp_freq_index(struct hmc5843_data *data,
281 for (i = 0; i < data->variant->n_regval_to_samp_freq; i++)
282 if (val == data->variant->regval_to_samp_freq[i][0] &&
283 val2 == data->variant->regval_to_samp_freq[i][1])
289 static int hmc5843_set_range_gain(struct hmc5843_data *data, u8 range)
293 mutex_lock(&data->lock);
294 ret = regmap_update_bits(data->regmap, HMC5843_CONFIG_REG_B,
295 HMC5843_RANGE_GAIN_MASK,
296 range << HMC5843_RANGE_GAIN_OFFSET);
297 mutex_unlock(&data->lock);
302 static ssize_t hmc5843_show_scale_avail(struct device *dev,
303 struct device_attribute *attr, char *buf)
305 struct hmc5843_data *data = iio_priv(dev_to_iio_dev(dev));
310 for (i = 0; i < data->variant->n_regval_to_nanoscale; i++)
311 len += scnprintf(buf + len, PAGE_SIZE - len,
312 "0.%09d ", data->variant->regval_to_nanoscale[i]);
314 /* replace trailing space by newline */
320 static IIO_DEVICE_ATTR(scale_available, S_IRUGO,
321 hmc5843_show_scale_avail, NULL, 0);
323 static int hmc5843_get_scale_index(struct hmc5843_data *data, int val, int val2)
330 for (i = 0; i < data->variant->n_regval_to_nanoscale; i++)
331 if (val2 == data->variant->regval_to_nanoscale[i])
337 static int hmc5843_read_raw(struct iio_dev *indio_dev,
338 struct iio_chan_spec const *chan,
339 int *val, int *val2, long mask)
341 struct hmc5843_data *data = iio_priv(indio_dev);
346 case IIO_CHAN_INFO_RAW:
347 return hmc5843_read_measurement(data, chan->scan_index, val);
348 case IIO_CHAN_INFO_SCALE:
349 ret = regmap_read(data->regmap, HMC5843_CONFIG_REG_B, &rval);
352 rval >>= HMC5843_RANGE_GAIN_OFFSET;
354 *val2 = data->variant->regval_to_nanoscale[rval];
355 return IIO_VAL_INT_PLUS_NANO;
356 case IIO_CHAN_INFO_SAMP_FREQ:
357 ret = regmap_read(data->regmap, HMC5843_CONFIG_REG_A, &rval);
360 rval >>= HMC5843_RATE_OFFSET;
361 *val = data->variant->regval_to_samp_freq[rval][0];
362 *val2 = data->variant->regval_to_samp_freq[rval][1];
363 return IIO_VAL_INT_PLUS_MICRO;
368 static int hmc5843_write_raw(struct iio_dev *indio_dev,
369 struct iio_chan_spec const *chan,
370 int val, int val2, long mask)
372 struct hmc5843_data *data = iio_priv(indio_dev);
376 case IIO_CHAN_INFO_SAMP_FREQ:
377 rate = hmc5843_get_samp_freq_index(data, val, val2);
381 return hmc5843_set_samp_freq(data, rate);
382 case IIO_CHAN_INFO_SCALE:
383 range = hmc5843_get_scale_index(data, val, val2);
387 return hmc5843_set_range_gain(data, range);
393 static int hmc5843_write_raw_get_fmt(struct iio_dev *indio_dev,
394 struct iio_chan_spec const *chan, long mask)
397 case IIO_CHAN_INFO_SAMP_FREQ:
398 return IIO_VAL_INT_PLUS_MICRO;
399 case IIO_CHAN_INFO_SCALE:
400 return IIO_VAL_INT_PLUS_NANO;
406 static irqreturn_t hmc5843_trigger_handler(int irq, void *p)
408 struct iio_poll_func *pf = p;
409 struct iio_dev *indio_dev = pf->indio_dev;
410 struct hmc5843_data *data = iio_priv(indio_dev);
413 mutex_lock(&data->lock);
414 ret = hmc5843_wait_measurement(data);
416 mutex_unlock(&data->lock);
420 ret = regmap_bulk_read(data->regmap, HMC5843_DATA_OUT_MSB_REGS,
421 data->buffer, 3 * sizeof(__be16));
423 mutex_unlock(&data->lock);
427 iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
431 iio_trigger_notify_done(indio_dev->trig);
436 #define HMC5843_CHANNEL(axis, idx) \
440 .channel2 = IIO_MOD_##axis, \
441 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
442 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
443 BIT(IIO_CHAN_INFO_SAMP_FREQ), \
449 .endianness = IIO_BE, \
453 static const struct iio_chan_spec hmc5843_channels[] = {
454 HMC5843_CHANNEL(X, 0),
455 HMC5843_CHANNEL(Y, 1),
456 HMC5843_CHANNEL(Z, 2),
457 IIO_CHAN_SOFT_TIMESTAMP(3),
460 /* Beware: Y and Z are exchanged on HMC5883 */
461 static const struct iio_chan_spec hmc5883_channels[] = {
462 HMC5843_CHANNEL(X, 0),
463 HMC5843_CHANNEL(Z, 1),
464 HMC5843_CHANNEL(Y, 2),
465 IIO_CHAN_SOFT_TIMESTAMP(3),
468 static struct attribute *hmc5843_attributes[] = {
469 &iio_dev_attr_meas_conf.dev_attr.attr,
470 &iio_dev_attr_scale_available.dev_attr.attr,
471 &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
475 static const struct attribute_group hmc5843_group = {
476 .attrs = hmc5843_attributes,
479 static const struct hmc5843_chip_info hmc5843_chip_info_tbl[] = {
481 .channels = hmc5843_channels,
482 .regval_to_samp_freq = hmc5843_regval_to_samp_freq,
483 .n_regval_to_samp_freq =
484 ARRAY_SIZE(hmc5843_regval_to_samp_freq),
485 .regval_to_nanoscale = hmc5843_regval_to_nanoscale,
486 .n_regval_to_nanoscale =
487 ARRAY_SIZE(hmc5843_regval_to_nanoscale),
490 .channels = hmc5883_channels,
491 .regval_to_samp_freq = hmc5883_regval_to_samp_freq,
492 .n_regval_to_samp_freq =
493 ARRAY_SIZE(hmc5883_regval_to_samp_freq),
494 .regval_to_nanoscale = hmc5883_regval_to_nanoscale,
495 .n_regval_to_nanoscale =
496 ARRAY_SIZE(hmc5883_regval_to_nanoscale),
499 .channels = hmc5883_channels,
500 .regval_to_samp_freq = hmc5883_regval_to_samp_freq,
501 .n_regval_to_samp_freq =
502 ARRAY_SIZE(hmc5883_regval_to_samp_freq),
503 .regval_to_nanoscale = hmc5883l_regval_to_nanoscale,
504 .n_regval_to_nanoscale =
505 ARRAY_SIZE(hmc5883l_regval_to_nanoscale),
509 static int hmc5843_init(struct hmc5843_data *data)
514 ret = regmap_bulk_read(data->regmap, HMC5843_ID_REG,
518 if (id[0] != 'H' || id[1] != '4' || id[2] != '3') {
519 dev_err(data->dev, "no HMC5843/5883/5883L sensor\n");
523 ret = hmc5843_set_meas_conf(data, HMC5843_MEAS_CONF_NORMAL);
526 ret = hmc5843_set_samp_freq(data, HMC5843_RATE_DEFAULT);
529 ret = hmc5843_set_range_gain(data, HMC5843_RANGE_GAIN_DEFAULT);
532 return hmc5843_set_mode(data, HMC5843_MODE_CONVERSION_CONTINUOUS);
535 static const struct iio_info hmc5843_info = {
536 .attrs = &hmc5843_group,
537 .read_raw = &hmc5843_read_raw,
538 .write_raw = &hmc5843_write_raw,
539 .write_raw_get_fmt = &hmc5843_write_raw_get_fmt,
540 .driver_module = THIS_MODULE,
543 static const unsigned long hmc5843_scan_masks[] = {0x7, 0};
546 int hmc5843_common_suspend(struct device *dev)
548 return hmc5843_set_mode(iio_priv(dev_get_drvdata(dev)),
549 HMC5843_MODE_CONVERSION_CONTINUOUS);
551 EXPORT_SYMBOL(hmc5843_common_suspend);
553 int hmc5843_common_resume(struct device *dev)
555 return hmc5843_set_mode(iio_priv(dev_get_drvdata(dev)),
558 EXPORT_SYMBOL(hmc5843_common_resume);
560 int hmc5843_common_probe(struct device *dev, struct regmap *regmap,
563 struct hmc5843_data *data;
564 struct iio_dev *indio_dev;
567 indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
568 if (indio_dev == NULL)
571 dev_set_drvdata(dev, indio_dev);
573 /* default settings at probe */
574 data = iio_priv(indio_dev);
576 data->regmap = regmap;
577 data->variant = &hmc5843_chip_info_tbl[id];
578 mutex_init(&data->lock);
580 indio_dev->dev.parent = dev;
581 indio_dev->info = &hmc5843_info;
582 indio_dev->modes = INDIO_DIRECT_MODE;
583 indio_dev->channels = data->variant->channels;
584 indio_dev->num_channels = 4;
585 indio_dev->available_scan_masks = hmc5843_scan_masks;
587 ret = hmc5843_init(data);
591 ret = iio_triggered_buffer_setup(indio_dev, NULL,
592 hmc5843_trigger_handler, NULL);
596 ret = iio_device_register(indio_dev);
603 iio_triggered_buffer_cleanup(indio_dev);
606 EXPORT_SYMBOL(hmc5843_common_probe);
608 int hmc5843_common_remove(struct device *dev)
610 struct iio_dev *indio_dev = dev_get_drvdata(dev);
612 iio_device_unregister(indio_dev);
613 iio_triggered_buffer_cleanup(indio_dev);
615 /* sleep mode to save power */
616 hmc5843_set_mode(iio_priv(indio_dev), HMC5843_MODE_SLEEP);
620 EXPORT_SYMBOL(hmc5843_common_remove);
622 MODULE_AUTHOR("Shubhrajyoti Datta <shubhrajyoti@ti.com>");
623 MODULE_DESCRIPTION("HMC5843/5883/5883L core driver");
624 MODULE_LICENSE("GPL");