2 * sca3000_core.c -- support VTI sca3000 series accelerometers via SPI
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 as published by
6 * the Free Software Foundation.
8 * Copyright (c) 2009 Jonathan Cameron <jic23@kernel.org>
10 * See industrialio/accels/sca3000.h for comments.
13 #include <linux/interrupt.h>
15 #include <linux/device.h>
16 #include <linux/slab.h>
17 #include <linux/kernel.h>
18 #include <linux/spi/spi.h>
19 #include <linux/sysfs.h>
20 #include <linux/module.h>
21 #include <linux/iio/iio.h>
22 #include <linux/iio/sysfs.h>
23 #include <linux/iio/events.h>
24 #include <linux/iio/buffer.h>
28 enum sca3000_variant {
36 * Note where option modes are not defined, the chip simply does not
38 * Other chips in the sca3000 series use i2c and are not included here.
40 * Some of these devices are only listed in the family data sheet and
41 * do not actually appear to be available.
43 static const struct sca3000_chip_info sca3000_spi_chip_info_tbl[] = {
47 .measurement_mode_freq = 250,
48 .option_mode_1 = SCA3000_OP_MODE_BYPASS,
49 .option_mode_1_freq = 250,
50 .mot_det_mult_xz = {50, 100, 200, 350, 650, 1300},
51 .mot_det_mult_y = {50, 100, 150, 250, 450, 850, 1750},
55 .measurement_mode_freq = 125,
56 .option_mode_1 = SCA3000_OP_MODE_NARROW,
57 .option_mode_1_freq = 63,
58 .mot_det_mult_xz = {100, 150, 300, 550, 1050, 2050},
59 .mot_det_mult_y = {50, 100, 200, 350, 700, 1350, 2700},
63 .measurement_mode_freq = 100,
64 .option_mode_1 = SCA3000_OP_MODE_NARROW,
65 .option_mode_1_freq = 50,
66 .option_mode_2 = SCA3000_OP_MODE_WIDE,
67 .option_mode_2_freq = 400,
68 .mot_det_mult_xz = {200, 300, 600, 1100, 2100, 4100},
69 .mot_det_mult_y = {100, 200, 400, 7000, 1400, 2700, 54000},
73 .measurement_mode_freq = 200,
74 .option_mode_1 = SCA3000_OP_MODE_NARROW,
75 .option_mode_1_freq = 50,
76 .option_mode_2 = SCA3000_OP_MODE_WIDE,
77 .option_mode_2_freq = 400,
78 .mot_det_mult_xz = {600, 900, 1700, 3200, 6100, 11900},
79 .mot_det_mult_y = {300, 600, 1200, 2000, 4100, 7800, 15600},
83 int sca3000_write_reg(struct sca3000_state *st, u8 address, u8 val)
85 st->tx[0] = SCA3000_WRITE_REG(address);
87 return spi_write(st->us, st->tx, 2);
90 int sca3000_read_data_short(struct sca3000_state *st,
94 struct spi_transfer xfer[2] = {
103 st->tx[0] = SCA3000_READ_REG(reg_address_high);
105 return spi_sync_transfer(st->us, xfer, ARRAY_SIZE(xfer));
109 * sca3000_reg_lock_on() test if the ctrl register lock is on
113 static int sca3000_reg_lock_on(struct sca3000_state *st)
117 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_STATUS, 1);
121 return !(st->rx[0] & SCA3000_LOCKED);
125 * __sca3000_unlock_reg_lock() unlock the control registers
127 * Note the device does not appear to support doing this in a single transfer.
128 * This should only ever be used as part of ctrl reg read.
129 * Lock must be held before calling this
131 static int __sca3000_unlock_reg_lock(struct sca3000_state *st)
133 struct spi_transfer xfer[3] = {
141 .tx_buf = st->tx + 2,
144 .tx_buf = st->tx + 4,
147 st->tx[0] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK);
149 st->tx[2] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK);
151 st->tx[4] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK);
154 return spi_sync_transfer(st->us, xfer, ARRAY_SIZE(xfer));
158 * sca3000_write_ctrl_reg() write to a lock protect ctrl register
159 * @sel: selects which registers we wish to write to
160 * @val: the value to be written
162 * Certain control registers are protected against overwriting by the lock
163 * register and use a shared write address. This function allows writing of
167 static int sca3000_write_ctrl_reg(struct sca3000_state *st,
173 ret = sca3000_reg_lock_on(st);
177 ret = __sca3000_unlock_reg_lock(st);
182 /* Set the control select register */
183 ret = sca3000_write_reg(st, SCA3000_REG_ADDR_CTRL_SEL, sel);
187 /* Write the actual value into the register */
188 ret = sca3000_write_reg(st, SCA3000_REG_ADDR_CTRL_DATA, val);
195 * sca3000_read_ctrl_reg() read from lock protected control register.
199 static int sca3000_read_ctrl_reg(struct sca3000_state *st,
204 ret = sca3000_reg_lock_on(st);
208 ret = __sca3000_unlock_reg_lock(st);
212 /* Set the control select register */
213 ret = sca3000_write_reg(st, SCA3000_REG_ADDR_CTRL_SEL, ctrl_reg);
216 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_CTRL_DATA, 1);
225 * sca3000_show_rev() - sysfs interface to read the chip revision number
227 static ssize_t sca3000_show_rev(struct device *dev,
228 struct device_attribute *attr,
232 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
233 struct sca3000_state *st = iio_priv(indio_dev);
235 mutex_lock(&st->lock);
236 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_REVID, 1);
239 len += sprintf(buf + len,
240 "major=%d, minor=%d\n",
241 st->rx[0] & SCA3000_REVID_MAJOR_MASK,
242 st->rx[0] & SCA3000_REVID_MINOR_MASK);
244 mutex_unlock(&st->lock);
246 return ret ? ret : len;
250 * sca3000_show_available_measurement_modes() display available modes
252 * This is all read from chip specific data in the driver. Not all
253 * of the sca3000 series support modes other than normal.
256 sca3000_show_available_measurement_modes(struct device *dev,
257 struct device_attribute *attr,
260 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
261 struct sca3000_state *st = iio_priv(indio_dev);
264 len += sprintf(buf + len, "0 - normal mode");
265 switch (st->info->option_mode_1) {
266 case SCA3000_OP_MODE_NARROW:
267 len += sprintf(buf + len, ", 1 - narrow mode");
269 case SCA3000_OP_MODE_BYPASS:
270 len += sprintf(buf + len, ", 1 - bypass mode");
273 switch (st->info->option_mode_2) {
274 case SCA3000_OP_MODE_WIDE:
275 len += sprintf(buf + len, ", 2 - wide mode");
278 /* always supported */
279 len += sprintf(buf + len, " 3 - motion detection\n");
285 * sca3000_show_measurement_mode() sysfs read of current mode
288 sca3000_show_measurement_mode(struct device *dev,
289 struct device_attribute *attr,
292 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
293 struct sca3000_state *st = iio_priv(indio_dev);
296 mutex_lock(&st->lock);
297 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
300 /* mask bottom 2 bits - only ones that are relevant */
303 case SCA3000_MEAS_MODE_NORMAL:
304 len += sprintf(buf + len, "0 - normal mode\n");
306 case SCA3000_MEAS_MODE_MOT_DET:
307 len += sprintf(buf + len, "3 - motion detection\n");
309 case SCA3000_MEAS_MODE_OP_1:
310 switch (st->info->option_mode_1) {
311 case SCA3000_OP_MODE_NARROW:
312 len += sprintf(buf + len, "1 - narrow mode\n");
314 case SCA3000_OP_MODE_BYPASS:
315 len += sprintf(buf + len, "1 - bypass mode\n");
319 case SCA3000_MEAS_MODE_OP_2:
320 switch (st->info->option_mode_2) {
321 case SCA3000_OP_MODE_WIDE:
322 len += sprintf(buf + len, "2 - wide mode\n");
329 mutex_unlock(&st->lock);
331 return ret ? ret : len;
335 * sca3000_store_measurement_mode() set the current mode
338 sca3000_store_measurement_mode(struct device *dev,
339 struct device_attribute *attr,
343 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
344 struct sca3000_state *st = iio_priv(indio_dev);
349 mutex_lock(&st->lock);
350 ret = kstrtou8(buf, 10, &val);
357 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
361 st->rx[0] |= (val & mask);
362 ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE, st->rx[0]);
365 mutex_unlock(&st->lock);
370 mutex_unlock(&st->lock);
376 * Not even vaguely standard attributes so defined here rather than
377 * in the relevant IIO core headers
379 static IIO_DEVICE_ATTR(measurement_mode_available, S_IRUGO,
380 sca3000_show_available_measurement_modes,
383 static IIO_DEVICE_ATTR(measurement_mode, S_IRUGO | S_IWUSR,
384 sca3000_show_measurement_mode,
385 sca3000_store_measurement_mode,
388 /* More standard attributes */
390 static IIO_DEVICE_ATTR(revision, S_IRUGO, sca3000_show_rev, NULL, 0);
392 static const struct iio_event_spec sca3000_event = {
393 .type = IIO_EV_TYPE_MAG,
394 .dir = IIO_EV_DIR_RISING,
395 .mask_separate = BIT(IIO_EV_INFO_VALUE) | BIT(IIO_EV_INFO_ENABLE),
398 #define SCA3000_CHAN(index, mod) \
403 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
404 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\
405 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
407 .scan_index = index, \
414 .event_spec = &sca3000_event, \
415 .num_event_specs = 1, \
418 static const struct iio_chan_spec sca3000_channels[] = {
419 SCA3000_CHAN(0, IIO_MOD_X),
420 SCA3000_CHAN(1, IIO_MOD_Y),
421 SCA3000_CHAN(2, IIO_MOD_Z),
424 static const struct iio_chan_spec sca3000_channels_with_temp[] = {
425 SCA3000_CHAN(0, IIO_MOD_X),
426 SCA3000_CHAN(1, IIO_MOD_Y),
427 SCA3000_CHAN(2, IIO_MOD_Z),
430 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
431 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |
432 BIT(IIO_CHAN_INFO_OFFSET),
433 /* No buffer support */
438 static u8 sca3000_addresses[3][3] = {
439 [0] = {SCA3000_REG_ADDR_X_MSB, SCA3000_REG_CTRL_SEL_MD_X_TH,
440 SCA3000_MD_CTRL_OR_X},
441 [1] = {SCA3000_REG_ADDR_Y_MSB, SCA3000_REG_CTRL_SEL_MD_Y_TH,
442 SCA3000_MD_CTRL_OR_Y},
443 [2] = {SCA3000_REG_ADDR_Z_MSB, SCA3000_REG_CTRL_SEL_MD_Z_TH,
444 SCA3000_MD_CTRL_OR_Z},
448 * __sca3000_get_base_freq() obtain mode specific base frequency
452 static inline int __sca3000_get_base_freq(struct sca3000_state *st,
453 const struct sca3000_chip_info *info,
458 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
461 switch (0x03 & st->rx[0]) {
462 case SCA3000_MEAS_MODE_NORMAL:
463 *base_freq = info->measurement_mode_freq;
465 case SCA3000_MEAS_MODE_OP_1:
466 *base_freq = info->option_mode_1_freq;
468 case SCA3000_MEAS_MODE_OP_2:
469 *base_freq = info->option_mode_2_freq;
477 * read_raw handler for IIO_CHAN_INFO_SAMP_FREQ
481 static int read_raw_samp_freq(struct sca3000_state *st, int *val)
485 ret = __sca3000_get_base_freq(st, st->info, val);
489 ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL);
494 ret &= SCA3000_OUT_CTRL_BUF_DIV_MASK;
496 case SCA3000_OUT_CTRL_BUF_DIV_2:
499 case SCA3000_OUT_CTRL_BUF_DIV_4:
509 * write_raw handler for IIO_CHAN_INFO_SAMP_FREQ
513 static int write_raw_samp_freq(struct sca3000_state *st, int val)
515 int ret, base_freq, ctrlval;
517 ret = __sca3000_get_base_freq(st, st->info, &base_freq);
521 ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL);
525 ctrlval = ret & ~SCA3000_OUT_CTRL_BUF_DIV_MASK;
527 if (val == base_freq / 2)
528 ctrlval |= SCA3000_OUT_CTRL_BUF_DIV_2;
529 if (val == base_freq / 4)
530 ctrlval |= SCA3000_OUT_CTRL_BUF_DIV_4;
531 else if (val != base_freq)
534 return sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL,
538 static int sca3000_read_raw(struct iio_dev *indio_dev,
539 struct iio_chan_spec const *chan,
544 struct sca3000_state *st = iio_priv(indio_dev);
549 case IIO_CHAN_INFO_RAW:
550 mutex_lock(&st->lock);
551 if (chan->type == IIO_ACCEL) {
552 if (st->mo_det_use_count) {
553 mutex_unlock(&st->lock);
556 address = sca3000_addresses[chan->address][0];
557 ret = sca3000_read_data_short(st, address, 2);
559 mutex_unlock(&st->lock);
562 *val = (be16_to_cpup((__be16 *)st->rx) >> 3) & 0x1FFF;
563 *val = ((*val) << (sizeof(*val) * 8 - 13)) >>
564 (sizeof(*val) * 8 - 13);
566 /* get the temperature when available */
567 ret = sca3000_read_data_short(st,
568 SCA3000_REG_ADDR_TEMP_MSB,
571 mutex_unlock(&st->lock);
574 *val = ((st->rx[0] & 0x3F) << 3) |
575 ((st->rx[1] & 0xE0) >> 5);
577 mutex_unlock(&st->lock);
579 case IIO_CHAN_INFO_SCALE:
581 if (chan->type == IIO_ACCEL)
582 *val2 = st->info->scale;
583 else /* temperature */
585 return IIO_VAL_INT_PLUS_MICRO;
586 case IIO_CHAN_INFO_OFFSET:
589 return IIO_VAL_INT_PLUS_MICRO;
590 case IIO_CHAN_INFO_SAMP_FREQ:
591 mutex_lock(&st->lock);
592 ret = read_raw_samp_freq(st, val);
593 mutex_unlock(&st->lock);
594 return ret ? ret : IIO_VAL_INT;
600 static int sca3000_write_raw(struct iio_dev *indio_dev,
601 struct iio_chan_spec const *chan,
602 int val, int val2, long mask)
604 struct sca3000_state *st = iio_priv(indio_dev);
608 case IIO_CHAN_INFO_SAMP_FREQ:
611 mutex_lock(&st->lock);
612 ret = write_raw_samp_freq(st, val);
613 mutex_unlock(&st->lock);
623 * sca3000_read_av_freq() sysfs function to get available frequencies
625 * The later modes are only relevant to the ring buffer - and depend on current
626 * mode. Note that data sheet gives rather wide tolerances for these so integer
627 * division will give good enough answer and not all chips have them specified
630 static ssize_t sca3000_read_av_freq(struct device *dev,
631 struct device_attribute *attr,
634 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
635 struct sca3000_state *st = iio_priv(indio_dev);
636 int len = 0, ret, val;
638 mutex_lock(&st->lock);
639 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
641 mutex_unlock(&st->lock);
645 switch (val & 0x03) {
646 case SCA3000_MEAS_MODE_NORMAL:
647 len += sprintf(buf + len, "%d %d %d\n",
648 st->info->measurement_mode_freq,
649 st->info->measurement_mode_freq / 2,
650 st->info->measurement_mode_freq / 4);
652 case SCA3000_MEAS_MODE_OP_1:
653 len += sprintf(buf + len, "%d %d %d\n",
654 st->info->option_mode_1_freq,
655 st->info->option_mode_1_freq / 2,
656 st->info->option_mode_1_freq / 4);
658 case SCA3000_MEAS_MODE_OP_2:
659 len += sprintf(buf + len, "%d %d %d\n",
660 st->info->option_mode_2_freq,
661 st->info->option_mode_2_freq / 2,
662 st->info->option_mode_2_freq / 4);
671 * Should only really be registered if ring buffer support is compiled in.
672 * Does no harm however and doing it right would add a fair bit of complexity
674 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(sca3000_read_av_freq);
677 * sca3000_read_thresh() - query of a threshold
679 static int sca3000_read_thresh(struct iio_dev *indio_dev,
680 const struct iio_chan_spec *chan,
681 enum iio_event_type type,
682 enum iio_event_direction dir,
683 enum iio_event_info info,
687 struct sca3000_state *st = iio_priv(indio_dev);
688 int num = chan->channel2;
690 mutex_lock(&st->lock);
691 ret = sca3000_read_ctrl_reg(st, sca3000_addresses[num][1]);
692 mutex_unlock(&st->lock);
697 for_each_set_bit(i, (unsigned long *)&ret,
698 ARRAY_SIZE(st->info->mot_det_mult_y))
699 *val += st->info->mot_det_mult_y[i];
701 for_each_set_bit(i, (unsigned long *)&ret,
702 ARRAY_SIZE(st->info->mot_det_mult_xz))
703 *val += st->info->mot_det_mult_xz[i];
709 * sca3000_write_thresh() control of threshold
711 static int sca3000_write_thresh(struct iio_dev *indio_dev,
712 const struct iio_chan_spec *chan,
713 enum iio_event_type type,
714 enum iio_event_direction dir,
715 enum iio_event_info info,
718 struct sca3000_state *st = iio_priv(indio_dev);
719 int num = chan->channel2;
725 i = ARRAY_SIZE(st->info->mot_det_mult_y);
727 if (val >= st->info->mot_det_mult_y[--i]) {
728 nonlinear |= (1 << i);
729 val -= st->info->mot_det_mult_y[i];
732 i = ARRAY_SIZE(st->info->mot_det_mult_xz);
734 if (val >= st->info->mot_det_mult_xz[--i]) {
735 nonlinear |= (1 << i);
736 val -= st->info->mot_det_mult_xz[i];
740 mutex_lock(&st->lock);
741 ret = sca3000_write_ctrl_reg(st, sca3000_addresses[num][1], nonlinear);
742 mutex_unlock(&st->lock);
747 static struct attribute *sca3000_attributes[] = {
748 &iio_dev_attr_revision.dev_attr.attr,
749 &iio_dev_attr_measurement_mode_available.dev_attr.attr,
750 &iio_dev_attr_measurement_mode.dev_attr.attr,
751 &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
755 static const struct attribute_group sca3000_attribute_group = {
756 .attrs = sca3000_attributes,
760 * sca3000_event_handler() - handling ring and non ring events
762 * Ring related interrupt handler. Depending on event, push to
763 * the ring buffer event chrdev or the event one.
765 * This function is complicated by the fact that the devices can signify ring
766 * and non ring events via the same interrupt line and they can only
767 * be distinguished via a read of the relevant status register.
769 static irqreturn_t sca3000_event_handler(int irq, void *private)
771 struct iio_dev *indio_dev = private;
772 struct sca3000_state *st = iio_priv(indio_dev);
774 s64 last_timestamp = iio_get_time_ns(indio_dev);
777 * Could lead if badly timed to an extra read of status reg,
778 * but ensures no interrupt is missed.
780 mutex_lock(&st->lock);
781 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_STATUS, 1);
783 mutex_unlock(&st->lock);
787 sca3000_ring_int_process(val, indio_dev->buffer);
789 if (val & SCA3000_INT_STATUS_FREE_FALL)
790 iio_push_event(indio_dev,
791 IIO_MOD_EVENT_CODE(IIO_ACCEL,
793 IIO_MOD_X_AND_Y_AND_Z,
798 if (val & SCA3000_INT_STATUS_Y_TRIGGER)
799 iio_push_event(indio_dev,
800 IIO_MOD_EVENT_CODE(IIO_ACCEL,
807 if (val & SCA3000_INT_STATUS_X_TRIGGER)
808 iio_push_event(indio_dev,
809 IIO_MOD_EVENT_CODE(IIO_ACCEL,
816 if (val & SCA3000_INT_STATUS_Z_TRIGGER)
817 iio_push_event(indio_dev,
818 IIO_MOD_EVENT_CODE(IIO_ACCEL,
830 * sca3000_read_event_config() what events are enabled
832 static int sca3000_read_event_config(struct iio_dev *indio_dev,
833 const struct iio_chan_spec *chan,
834 enum iio_event_type type,
835 enum iio_event_direction dir)
837 struct sca3000_state *st = iio_priv(indio_dev);
839 u8 protect_mask = 0x03;
840 int num = chan->channel2;
842 /* read current value of mode register */
843 mutex_lock(&st->lock);
844 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
848 if ((st->rx[0] & protect_mask) != SCA3000_MEAS_MODE_MOT_DET) {
851 ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL);
854 /* only supporting logical or's for now */
855 ret = !!(ret & sca3000_addresses[num][2]);
858 mutex_unlock(&st->lock);
864 * sca3000_query_free_fall_mode() is free fall mode enabled
866 static ssize_t sca3000_query_free_fall_mode(struct device *dev,
867 struct device_attribute *attr,
871 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
872 struct sca3000_state *st = iio_priv(indio_dev);
875 mutex_lock(&st->lock);
876 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
878 mutex_unlock(&st->lock);
881 return sprintf(buf, "%d\n", !!(val & SCA3000_FREE_FALL_DETECT));
885 * sca3000_set_free_fall_mode() simple on off control for free fall int
887 * In these chips the free fall detector should send an interrupt if
888 * the device falls more than 25cm. This has not been tested due
891 static ssize_t sca3000_set_free_fall_mode(struct device *dev,
892 struct device_attribute *attr,
896 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
897 struct sca3000_state *st = iio_priv(indio_dev);
900 u8 protect_mask = SCA3000_FREE_FALL_DETECT;
902 mutex_lock(&st->lock);
903 ret = kstrtou8(buf, 10, &val);
907 /* read current value of mode register */
908 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
912 /* if off and should be on */
913 if (val && !(st->rx[0] & protect_mask))
914 ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
915 (st->rx[0] | SCA3000_FREE_FALL_DETECT));
916 /* if on and should be off */
917 else if (!val && (st->rx[0] & protect_mask))
918 ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
919 (st->rx[0] & ~protect_mask));
921 mutex_unlock(&st->lock);
923 return ret ? ret : len;
927 * sca3000_write_event_config() simple on off control for motion detector
929 * This is a per axis control, but enabling any will result in the
930 * motion detector unit being enabled.
931 * N.B. enabling motion detector stops normal data acquisition.
932 * There is a complexity in knowing which mode to return to when
933 * this mode is disabled. Currently normal mode is assumed.
935 static int sca3000_write_event_config(struct iio_dev *indio_dev,
936 const struct iio_chan_spec *chan,
937 enum iio_event_type type,
938 enum iio_event_direction dir,
941 struct sca3000_state *st = iio_priv(indio_dev);
943 u8 protect_mask = 0x03;
944 int num = chan->channel2;
946 mutex_lock(&st->lock);
948 * First read the motion detector config to find out if
951 ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL);
955 /* if off and should be on */
956 if (state && !(ctrlval & sca3000_addresses[num][2])) {
957 ret = sca3000_write_ctrl_reg(st,
958 SCA3000_REG_CTRL_SEL_MD_CTRL,
960 sca3000_addresses[num][2]);
963 st->mo_det_use_count++;
964 } else if (!state && (ctrlval & sca3000_addresses[num][2])) {
965 ret = sca3000_write_ctrl_reg(st,
966 SCA3000_REG_CTRL_SEL_MD_CTRL,
968 ~(sca3000_addresses[num][2]));
971 st->mo_det_use_count--;
974 /* read current value of mode register */
975 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
978 /* if off and should be on */
979 if ((st->mo_det_use_count) &&
980 ((st->rx[0] & protect_mask) != SCA3000_MEAS_MODE_MOT_DET))
981 ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
982 (st->rx[0] & ~protect_mask)
983 | SCA3000_MEAS_MODE_MOT_DET);
984 /* if on and should be off */
985 else if (!(st->mo_det_use_count) &&
986 ((st->rx[0] & protect_mask) == SCA3000_MEAS_MODE_MOT_DET))
987 ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
988 (st->rx[0] & ~protect_mask));
990 mutex_unlock(&st->lock);
995 /* Free fall detector related event attribute */
996 static IIO_DEVICE_ATTR_NAMED(accel_xayaz_mag_falling_en,
997 in_accel_x & y & z_mag_falling_en,
999 sca3000_query_free_fall_mode,
1000 sca3000_set_free_fall_mode,
1003 static IIO_CONST_ATTR_NAMED(accel_xayaz_mag_falling_period,
1004 in_accel_x & y & z_mag_falling_period,
1007 static struct attribute *sca3000_event_attributes[] = {
1008 &iio_dev_attr_accel_xayaz_mag_falling_en.dev_attr.attr,
1009 &iio_const_attr_accel_xayaz_mag_falling_period.dev_attr.attr,
1013 static struct attribute_group sca3000_event_attribute_group = {
1014 .attrs = sca3000_event_attributes,
1019 * sca3000_clean_setup() get the device into a predictable state
1021 * Devices use flash memory to store many of the register values
1022 * and hence can come up in somewhat unpredictable states.
1023 * Hence reset everything on driver load.
1025 static int sca3000_clean_setup(struct sca3000_state *st)
1029 mutex_lock(&st->lock);
1030 /* Ensure all interrupts have been acknowledged */
1031 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_STATUS, 1);
1035 /* Turn off all motion detection channels */
1036 ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL);
1039 ret = sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL,
1040 ret & SCA3000_MD_CTRL_PROT_MASK);
1044 /* Disable ring buffer */
1045 ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL);
1048 ret = sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL,
1049 (ret & SCA3000_OUT_CTRL_PROT_MASK)
1050 | SCA3000_OUT_CTRL_BUF_X_EN
1051 | SCA3000_OUT_CTRL_BUF_Y_EN
1052 | SCA3000_OUT_CTRL_BUF_Z_EN
1053 | SCA3000_OUT_CTRL_BUF_DIV_4);
1056 /* Enable interrupts, relevant to mode and set up as active low */
1057 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_MASK, 1);
1060 ret = sca3000_write_reg(st,
1061 SCA3000_REG_ADDR_INT_MASK,
1062 (ret & SCA3000_INT_MASK_PROT_MASK)
1063 | SCA3000_INT_MASK_ACTIVE_LOW);
1067 * Select normal measurement mode, free fall off, ring off
1068 * Ring in 12 bit mode - it is fine to overwrite reserved bits 3,5
1069 * as that occurs in one of the example on the datasheet
1071 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
1074 ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
1075 (st->rx[0] & SCA3000_MODE_PROT_MASK));
1079 mutex_unlock(&st->lock);
1083 static const struct iio_info sca3000_info = {
1084 .attrs = &sca3000_attribute_group,
1085 .read_raw = &sca3000_read_raw,
1086 .write_raw = &sca3000_write_raw,
1087 .event_attrs = &sca3000_event_attribute_group,
1088 .read_event_value = &sca3000_read_thresh,
1089 .write_event_value = &sca3000_write_thresh,
1090 .read_event_config = &sca3000_read_event_config,
1091 .write_event_config = &sca3000_write_event_config,
1092 .driver_module = THIS_MODULE,
1095 static int sca3000_probe(struct spi_device *spi)
1098 struct sca3000_state *st;
1099 struct iio_dev *indio_dev;
1101 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
1105 st = iio_priv(indio_dev);
1106 spi_set_drvdata(spi, indio_dev);
1108 mutex_init(&st->lock);
1109 st->info = &sca3000_spi_chip_info_tbl[spi_get_device_id(spi)
1112 indio_dev->dev.parent = &spi->dev;
1113 indio_dev->name = spi_get_device_id(spi)->name;
1114 indio_dev->info = &sca3000_info;
1115 if (st->info->temp_output) {
1116 indio_dev->channels = sca3000_channels_with_temp;
1117 indio_dev->num_channels =
1118 ARRAY_SIZE(sca3000_channels_with_temp);
1120 indio_dev->channels = sca3000_channels;
1121 indio_dev->num_channels = ARRAY_SIZE(sca3000_channels);
1123 indio_dev->modes = INDIO_DIRECT_MODE;
1125 sca3000_configure_ring(indio_dev);
1126 ret = iio_device_register(indio_dev);
1131 ret = request_threaded_irq(spi->irq,
1133 &sca3000_event_handler,
1134 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
1138 goto error_unregister_dev;
1140 sca3000_register_ring_funcs(indio_dev);
1141 ret = sca3000_clean_setup(st);
1143 goto error_free_irq;
1148 free_irq(spi->irq, indio_dev);
1149 error_unregister_dev:
1150 iio_device_unregister(indio_dev);
1154 static int sca3000_stop_all_interrupts(struct sca3000_state *st)
1158 mutex_lock(&st->lock);
1159 ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_MASK, 1);
1162 ret = sca3000_write_reg(st, SCA3000_REG_ADDR_INT_MASK,
1164 ~(SCA3000_INT_MASK_RING_THREE_QUARTER |
1165 SCA3000_INT_MASK_RING_HALF |
1166 SCA3000_INT_MASK_ALL_INTS)));
1168 mutex_unlock(&st->lock);
1172 static int sca3000_remove(struct spi_device *spi)
1174 struct iio_dev *indio_dev = spi_get_drvdata(spi);
1175 struct sca3000_state *st = iio_priv(indio_dev);
1177 /* Must ensure no interrupts can be generated after this! */
1178 sca3000_stop_all_interrupts(st);
1180 free_irq(spi->irq, indio_dev);
1181 iio_device_unregister(indio_dev);
1182 sca3000_unconfigure_ring(indio_dev);
1187 static const struct spi_device_id sca3000_id[] = {
1188 {"sca3000_d01", d01},
1189 {"sca3000_e02", e02},
1190 {"sca3000_e04", e04},
1191 {"sca3000_e05", e05},
1194 MODULE_DEVICE_TABLE(spi, sca3000_id);
1196 static struct spi_driver sca3000_driver = {
1200 .probe = sca3000_probe,
1201 .remove = sca3000_remove,
1202 .id_table = sca3000_id,
1204 module_spi_driver(sca3000_driver);
1206 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1207 MODULE_DESCRIPTION("VTI SCA3000 Series Accelerometers SPI driver");
1208 MODULE_LICENSE("GPL v2");