1 #include <linux/interrupt.h>
3 #include <linux/gpio.h>
4 #include <linux/workqueue.h>
5 #include <linux/mutex.h>
6 #include <linux/device.h>
7 #include <linux/kernel.h>
8 #include <linux/spi/spi.h>
9 #include <linux/sysfs.h>
10 #include <linux/list.h>
11 #include <linux/slab.h>
15 #include "../ring_sw.h"
17 #include "../trigger.h"
18 #include "lis3l02dq.h"
21 * combine_8_to_16() utility function to munge to u8s into u16
23 static inline u16 combine_8_to_16(u8 lower, u8 upper)
27 return _lower | (_upper << 8);
31 * lis3l02dq_scan_el_set_state() set whether a scan contains a given channel
32 * @scan_el: associtate iio scan element attribute
33 * @indio_dev: the device structure
34 * @bool: desired state
36 * mlock already held when this is called.
38 static int lis3l02dq_scan_el_set_state(struct iio_scan_el *scan_el,
39 struct iio_dev *indio_dev,
45 ret = lis3l02dq_spi_read_reg_8(&indio_dev->dev,
46 LIS3L02DQ_REG_CTRL_1_ADDR,
50 switch (scan_el->label) {
51 case LIS3L02DQ_REG_OUT_X_L_ADDR:
52 mask = LIS3L02DQ_REG_CTRL_1_AXES_X_ENABLE;
54 case LIS3L02DQ_REG_OUT_Y_L_ADDR:
55 mask = LIS3L02DQ_REG_CTRL_1_AXES_Y_ENABLE;
57 case LIS3L02DQ_REG_OUT_Z_L_ADDR:
58 mask = LIS3L02DQ_REG_CTRL_1_AXES_Z_ENABLE;
65 if (!(mask & t) == state) {
70 ret = lis3l02dq_spi_write_reg_8(&indio_dev->dev,
71 LIS3L02DQ_REG_CTRL_1_ADDR,
78 static IIO_SCAN_EL_C(accel_x, 0, IIO_SIGNED(16),
79 LIS3L02DQ_REG_OUT_X_L_ADDR,
80 &lis3l02dq_scan_el_set_state);
81 static IIO_SCAN_EL_C(accel_y, 1, IIO_SIGNED(16),
82 LIS3L02DQ_REG_OUT_Y_L_ADDR,
83 &lis3l02dq_scan_el_set_state);
84 static IIO_SCAN_EL_C(accel_z, 2, IIO_SIGNED(16),
85 LIS3L02DQ_REG_OUT_Z_L_ADDR,
86 &lis3l02dq_scan_el_set_state);
87 static IIO_SCAN_EL_TIMESTAMP(3);
89 static struct attribute *lis3l02dq_scan_el_attrs[] = {
90 &iio_scan_el_accel_x.dev_attr.attr,
91 &iio_scan_el_accel_y.dev_attr.attr,
92 &iio_scan_el_accel_z.dev_attr.attr,
93 &iio_scan_el_timestamp.dev_attr.attr,
97 static struct attribute_group lis3l02dq_scan_el_group = {
98 .attrs = lis3l02dq_scan_el_attrs,
99 .name = "scan_elements",
103 * lis3l02dq_poll_func_th() top half interrupt handler called by trigger
104 * @private_data: iio_dev
106 static void lis3l02dq_poll_func_th(struct iio_dev *indio_dev)
108 struct lis3l02dq_state *st = iio_dev_get_devdata(indio_dev);
109 st->last_timestamp = indio_dev->trig->timestamp;
110 schedule_work(&st->work_trigger_to_ring);
111 /* Indicate that this interrupt is being handled */
113 /* Technically this is trigger related, but without this
114 * handler running there is currently now way for the interrupt
121 * lis3l02dq_data_rdy_trig_poll() the event handler for the data rdy trig
123 static int lis3l02dq_data_rdy_trig_poll(struct iio_dev *dev_info,
128 struct lis3l02dq_state *st = iio_dev_get_devdata(dev_info);
129 struct iio_trigger *trig = st->trig;
131 trig->timestamp = timestamp;
132 iio_trigger_poll(trig);
137 /* This is an event as it is a response to a physical interrupt */
138 IIO_EVENT_SH(data_rdy_trig, &lis3l02dq_data_rdy_trig_poll);
141 * lis3l02dq_read_accel_from_ring() individual acceleration read from ring
143 ssize_t lis3l02dq_read_accel_from_ring(struct device *dev,
144 struct device_attribute *attr,
147 struct iio_scan_el *el = NULL;
148 int ret, len = 0, i = 0;
149 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
150 struct iio_dev *dev_info = dev_get_drvdata(dev);
153 while (dev_info->scan_el_attrs->attrs[i]) {
154 el = to_iio_scan_el((struct device_attribute *)
155 (dev_info->scan_el_attrs->attrs[i]));
156 /* label is in fact the address */
157 if (el->label == this_attr->address)
161 if (!dev_info->scan_el_attrs->attrs[i]) {
165 /* If this element is in the scan mask */
166 ret = iio_scan_mask_query(dev_info, el->number);
170 data = kmalloc(dev_info->ring->access.get_bpd(dev_info->ring),
174 ret = dev_info->ring->access.read_last(dev_info->ring,
177 goto error_free_data;
182 len = iio_scan_mask_count_to_right(dev_info, el->number);
185 goto error_free_data;
187 len = sprintf(buf, "ring %d\n", data[len]);
191 return ret ? ret : len;
195 static const u8 read_all_tx_array[] = {
196 LIS3L02DQ_READ_REG(LIS3L02DQ_REG_OUT_X_L_ADDR), 0,
197 LIS3L02DQ_READ_REG(LIS3L02DQ_REG_OUT_X_H_ADDR), 0,
198 LIS3L02DQ_READ_REG(LIS3L02DQ_REG_OUT_Y_L_ADDR), 0,
199 LIS3L02DQ_READ_REG(LIS3L02DQ_REG_OUT_Y_H_ADDR), 0,
200 LIS3L02DQ_READ_REG(LIS3L02DQ_REG_OUT_Z_L_ADDR), 0,
201 LIS3L02DQ_READ_REG(LIS3L02DQ_REG_OUT_Z_H_ADDR), 0,
205 * lis3l02dq_read_all() Reads all channels currently selected
206 * @st: device specific state
207 * @rx_array: (dma capable) recieve array, must be at least
208 * 4*number of channels
210 static int lis3l02dq_read_all(struct lis3l02dq_state *st, u8 *rx_array)
212 struct spi_transfer *xfers;
213 struct spi_message msg;
216 xfers = kzalloc((st->indio_dev->scan_count) * 2
217 * sizeof(*xfers), GFP_KERNEL);
221 mutex_lock(&st->buf_lock);
223 for (i = 0; i < ARRAY_SIZE(read_all_tx_array)/4; i++) {
224 if (st->indio_dev->scan_mask & (1 << i)) {
226 xfers[j].tx_buf = st->tx + 2*j;
227 st->tx[2*j] = read_all_tx_array[i*4];
230 xfers[j].rx_buf = rx_array + j*2;
231 xfers[j].bits_per_word = 8;
233 xfers[j].cs_change = 1;
237 xfers[j].tx_buf = st->tx + 2*j;
238 st->tx[2*j] = read_all_tx_array[i*4 + 2];
241 xfers[j].rx_buf = rx_array + j*2;
242 xfers[j].bits_per_word = 8;
244 xfers[j].cs_change = 1;
248 /* After these are transmitted, the rx_buff should have
249 * values in alternate bytes
251 spi_message_init(&msg);
252 for (j = 0; j < st->indio_dev->scan_count * 2; j++)
253 spi_message_add_tail(&xfers[j], &msg);
255 ret = spi_sync(st->us, &msg);
256 mutex_unlock(&st->buf_lock);
263 /* Whilst this makes a lot of calls to iio_sw_ring functions - it is to device
264 * specific to be rolled into the core.
266 static void lis3l02dq_trigger_bh_to_ring(struct work_struct *work_s)
268 struct lis3l02dq_state *st
269 = container_of(work_s, struct lis3l02dq_state,
270 work_trigger_to_ring);
275 size_t datasize = st->indio_dev
276 ->ring->access.get_bpd(st->indio_dev->ring);
278 data = kmalloc(datasize , GFP_KERNEL);
280 dev_err(&st->us->dev, "memory alloc failed in ring bh");
283 /* Due to interleaved nature of transmission this buffer must be
284 * twice the number of bytes, or 4 times the number of channels
286 rx_array = kmalloc(4 * (st->indio_dev->scan_count), GFP_KERNEL);
287 if (rx_array == NULL) {
288 dev_err(&st->us->dev, "memory alloc failed in ring bh");
293 /* whilst trigger specific, if this read does nto occur the data
294 ready interrupt will not be cleared. Need to add a mechanism
295 to provide a dummy read function if this is not triggering on
296 the data ready function but something else is.
300 if (st->indio_dev->scan_count)
301 if (lis3l02dq_read_all(st, rx_array) >= 0)
302 for (; i < st->indio_dev->scan_count; i++)
303 data[i] = combine_8_to_16(rx_array[i*4+1],
305 /* Guaranteed to be aligned with 8 byte boundary */
306 if (st->indio_dev->scan_timestamp)
307 *((s64 *)(data + ((i + 3)/4)*4)) = st->last_timestamp;
309 st->indio_dev->ring->access.store_to(st->indio_dev->ring,
313 iio_trigger_notify_done(st->indio_dev->trig);
319 /* in these circumstances is it better to go with unaligned packing and
320 * deal with the cost?*/
321 static int lis3l02dq_data_rdy_ring_preenable(struct iio_dev *indio_dev)
324 /* Check if there are any scan elements enabled, if not fail*/
325 if (!(indio_dev->scan_count || indio_dev->scan_timestamp))
328 if (indio_dev->ring->access.set_bpd) {
329 if (indio_dev->scan_timestamp)
330 if (indio_dev->scan_count) /* Timestamp and data */
331 size = 2*sizeof(s64);
332 else /* Timestamp only */
335 size = indio_dev->scan_count*sizeof(s16);
336 indio_dev->ring->access.set_bpd(indio_dev->ring, size);
342 static int lis3l02dq_data_rdy_ring_postenable(struct iio_dev *indio_dev)
344 return indio_dev->trig
345 ? iio_trigger_attach_poll_func(indio_dev->trig,
350 static int lis3l02dq_data_rdy_ring_predisable(struct iio_dev *indio_dev)
352 return indio_dev->trig
353 ? iio_trigger_dettach_poll_func(indio_dev->trig,
359 /* Caller responsible for locking as necessary. */
361 __lis3l02dq_write_data_ready_config(struct device *dev,
362 struct iio_event_handler_list *list,
368 struct iio_dev *indio_dev = dev_get_drvdata(dev);
370 /* Get the current event mask register */
371 ret = lis3l02dq_spi_read_reg_8(dev,
372 LIS3L02DQ_REG_CTRL_2_ADDR,
376 /* Find out if data ready is already on */
378 = valold & LIS3L02DQ_REG_CTRL_2_ENABLE_DATA_READY_GENERATION;
380 /* Disable requested */
381 if (!state && currentlyset) {
383 valold &= ~LIS3L02DQ_REG_CTRL_2_ENABLE_DATA_READY_GENERATION;
384 /* The double write is to overcome a hardware bug?*/
385 ret = lis3l02dq_spi_write_reg_8(dev,
386 LIS3L02DQ_REG_CTRL_2_ADDR,
390 ret = lis3l02dq_spi_write_reg_8(dev,
391 LIS3L02DQ_REG_CTRL_2_ADDR,
396 iio_remove_event_from_list(list,
397 &indio_dev->interrupts[0]
400 /* Enable requested */
401 } else if (state && !currentlyset) {
402 /* if not set, enable requested */
403 valold |= LIS3L02DQ_REG_CTRL_2_ENABLE_DATA_READY_GENERATION;
404 iio_add_event_to_list(list, &indio_dev->interrupts[0]->ev_list);
405 ret = lis3l02dq_spi_write_reg_8(dev,
406 LIS3L02DQ_REG_CTRL_2_ADDR,
418 * lis3l02dq_data_rdy_trigger_set_state() set datardy interrupt state
420 * If disabling the interrupt also does a final read to ensure it is clear.
421 * This is only important in some cases where the scan enable elements are
422 * switched before the ring is reenabled.
424 static int lis3l02dq_data_rdy_trigger_set_state(struct iio_trigger *trig,
427 struct lis3l02dq_state *st = trig->private_data;
430 __lis3l02dq_write_data_ready_config(&st->indio_dev->dev,
431 &iio_event_data_rdy_trig,
433 if (state == false) {
434 /* possible quirk with handler currently worked around
435 by ensuring the work queue is empty */
436 flush_scheduled_work();
437 /* Clear any outstanding ready events */
438 ret = lis3l02dq_read_all(st, NULL);
440 lis3l02dq_spi_read_reg_8(&st->indio_dev->dev,
441 LIS3L02DQ_REG_WAKE_UP_SRC_ADDR,
445 static DEVICE_ATTR(name, S_IRUGO, iio_trigger_read_name, NULL);
447 static struct attribute *lis3l02dq_trigger_attrs[] = {
452 static const struct attribute_group lis3l02dq_trigger_attr_group = {
453 .attrs = lis3l02dq_trigger_attrs,
457 * lis3l02dq_trig_try_reen() try renabling irq for data rdy trigger
458 * @trig: the datardy trigger
460 * As the trigger may occur on any data element being updated it is
461 * really rather likely to occur during the read from the previous
462 * trigger event. The only way to discover if this has occured on
463 * boards not supporting level interrupts is to take a look at the line.
464 * If it is indicating another interrupt and we don't seem to have a
465 * handler looking at it, then we need to notify the core that we need
466 * to tell the triggering core to try reading all these again.
468 static int lis3l02dq_trig_try_reen(struct iio_trigger *trig)
470 struct lis3l02dq_state *st = trig->private_data;
471 enable_irq(st->us->irq);
472 /* If gpio still high (or high again) */
473 if (gpio_get_value(irq_to_gpio(st->us->irq)))
474 if (st->inter == 0) {
475 /* already interrupt handler dealing with it */
476 disable_irq_nosync(st->us->irq);
477 if (st->inter == 1) {
478 /* interrupt handler snuck in between test
480 enable_irq(st->us->irq);
485 /* irq reenabled so success! */
489 int lis3l02dq_probe_trigger(struct iio_dev *indio_dev)
492 struct lis3l02dq_state *state = indio_dev->dev_data;
494 state->trig = iio_allocate_trigger();
498 state->trig->name = kmalloc(IIO_TRIGGER_NAME_LENGTH, GFP_KERNEL);
499 if (!state->trig->name) {
501 goto error_free_trig;
503 snprintf((char *)state->trig->name,
504 IIO_TRIGGER_NAME_LENGTH,
505 "lis3l02dq-dev%d", indio_dev->id);
506 state->trig->dev.parent = &state->us->dev;
507 state->trig->owner = THIS_MODULE;
508 state->trig->private_data = state;
509 state->trig->set_trigger_state = &lis3l02dq_data_rdy_trigger_set_state;
510 state->trig->try_reenable = &lis3l02dq_trig_try_reen;
511 state->trig->control_attrs = &lis3l02dq_trigger_attr_group;
512 ret = iio_trigger_register(state->trig);
514 goto error_free_trig_name;
518 error_free_trig_name:
519 kfree(state->trig->name);
521 iio_free_trigger(state->trig);
526 void lis3l02dq_remove_trigger(struct iio_dev *indio_dev)
528 struct lis3l02dq_state *state = indio_dev->dev_data;
530 iio_trigger_unregister(state->trig);
531 kfree(state->trig->name);
532 iio_free_trigger(state->trig);
535 void lis3l02dq_unconfigure_ring(struct iio_dev *indio_dev)
537 kfree(indio_dev->pollfunc);
538 iio_sw_rb_free(indio_dev->ring);
541 int lis3l02dq_configure_ring(struct iio_dev *indio_dev)
544 struct lis3l02dq_state *st = indio_dev->dev_data;
545 struct iio_ring_buffer *ring;
546 INIT_WORK(&st->work_trigger_to_ring, lis3l02dq_trigger_bh_to_ring);
547 /* Set default scan mode */
549 iio_scan_mask_set(indio_dev, iio_scan_el_accel_x.number);
550 iio_scan_mask_set(indio_dev, iio_scan_el_accel_y.number);
551 iio_scan_mask_set(indio_dev, iio_scan_el_accel_z.number);
552 indio_dev->scan_timestamp = true;
554 indio_dev->scan_el_attrs = &lis3l02dq_scan_el_group;
556 ring = iio_sw_rb_allocate(indio_dev);
561 indio_dev->ring = ring;
562 /* Effectively select the ring buffer implementation */
563 iio_ring_sw_register_funcs(&ring->access);
564 ring->preenable = &lis3l02dq_data_rdy_ring_preenable;
565 ring->postenable = &lis3l02dq_data_rdy_ring_postenable;
566 ring->predisable = &lis3l02dq_data_rdy_ring_predisable;
567 ring->owner = THIS_MODULE;
569 indio_dev->pollfunc = kzalloc(sizeof(*indio_dev->pollfunc), GFP_KERNEL);
570 if (indio_dev->pollfunc == NULL) {
572 goto error_iio_sw_rb_free;;
574 indio_dev->pollfunc->poll_func_main = &lis3l02dq_poll_func_th;
575 indio_dev->pollfunc->private_data = indio_dev;
576 indio_dev->modes |= INDIO_RING_TRIGGERED;
579 error_iio_sw_rb_free:
580 iio_sw_rb_free(indio_dev->ring);
584 int lis3l02dq_initialize_ring(struct iio_ring_buffer *ring)
586 return iio_ring_buffer_register(ring, 0);
589 void lis3l02dq_uninitialize_ring(struct iio_ring_buffer *ring)
591 iio_ring_buffer_unregister(ring);
594 int lis3l02dq_set_ring_length(struct iio_dev *indio_dev, int length)
596 /* Set sensible defaults for the ring buffer */
597 if (indio_dev->ring->access.set_length)
598 return indio_dev->ring->access.set_length(indio_dev->ring, 500);