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>
14 #include "../ring_sw.h"
16 #include "../trigger.h"
17 #include "lis3l02dq.h"
20 * combine_8_to_16() utility function to munge to u8s into u16
22 static inline u16 combine_8_to_16(u8 lower, u8 upper)
26 return _lower | (_upper << 8);
30 * lis3l02dq_scan_el_set_state() set whether a scan contains a given channel
31 * @scan_el: associtate iio scan element attribute
32 * @indio_dev: the device structure
33 * @bool: desired state
35 * mlock already held when this is called.
37 static int lis3l02dq_scan_el_set_state(struct iio_scan_el *scan_el,
38 struct iio_dev *indio_dev,
44 ret = lis3l02dq_spi_read_reg_8(&indio_dev->dev,
45 LIS3L02DQ_REG_CTRL_1_ADDR,
49 switch (scan_el->label) {
50 case LIS3L02DQ_REG_OUT_X_L_ADDR:
51 mask = LIS3L02DQ_REG_CTRL_1_AXES_X_ENABLE;
53 case LIS3L02DQ_REG_OUT_Y_L_ADDR:
54 mask = LIS3L02DQ_REG_CTRL_1_AXES_Y_ENABLE;
56 case LIS3L02DQ_REG_OUT_Z_L_ADDR:
57 mask = LIS3L02DQ_REG_CTRL_1_AXES_Z_ENABLE;
64 if (!(mask & t) == state) {
69 ret = lis3l02dq_spi_write_reg_8(&indio_dev->dev,
70 LIS3L02DQ_REG_CTRL_1_ADDR,
77 static IIO_SCAN_EL_C(accel_x, LIS3L02DQ_SCAN_ACC_X, IIO_SIGNED(16),
78 LIS3L02DQ_REG_OUT_X_L_ADDR,
79 &lis3l02dq_scan_el_set_state);
80 static IIO_SCAN_EL_C(accel_y, LIS3L02DQ_SCAN_ACC_Y, IIO_SIGNED(16),
81 LIS3L02DQ_REG_OUT_Y_L_ADDR,
82 &lis3l02dq_scan_el_set_state);
83 static IIO_SCAN_EL_C(accel_z, LIS3L02DQ_SCAN_ACC_Z, IIO_SIGNED(16),
84 LIS3L02DQ_REG_OUT_Z_L_ADDR,
85 &lis3l02dq_scan_el_set_state);
86 static IIO_SCAN_EL_TIMESTAMP;
88 static struct attribute *lis3l02dq_scan_el_attrs[] = {
89 &iio_scan_el_accel_x.dev_attr.attr,
90 &iio_scan_el_accel_y.dev_attr.attr,
91 &iio_scan_el_accel_z.dev_attr.attr,
92 &iio_scan_el_timestamp.dev_attr.attr,
96 static struct attribute_group lis3l02dq_scan_el_group = {
97 .attrs = lis3l02dq_scan_el_attrs,
98 .name = "scan_elements",
102 * lis3l02dq_poll_func_th() top half interrupt handler called by trigger
103 * @private_data: iio_dev
105 static void lis3l02dq_poll_func_th(struct iio_dev *indio_dev)
107 struct lis3l02dq_state *st = iio_dev_get_devdata(indio_dev);
108 st->last_timestamp = indio_dev->trig->timestamp;
109 schedule_work(&st->work_trigger_to_ring);
110 /* Indicate that this interrupt is being handled */
112 /* Technically this is trigger related, but without this
113 * handler running there is currently now way for the interrupt
120 * lis3l02dq_data_rdy_trig_poll() the event handler for the data rdy trig
122 static int lis3l02dq_data_rdy_trig_poll(struct iio_dev *dev_info,
127 struct lis3l02dq_state *st = iio_dev_get_devdata(dev_info);
128 struct iio_trigger *trig = st->trig;
130 trig->timestamp = timestamp;
131 iio_trigger_poll(trig);
136 /* This is an event as it is a response to a physical interrupt */
137 IIO_EVENT_SH(data_rdy_trig, &lis3l02dq_data_rdy_trig_poll);
140 * lis3l02dq_read_accel_from_ring() individual acceleration read from ring
142 ssize_t lis3l02dq_read_accel_from_ring(struct device *dev,
143 struct device_attribute *attr,
146 struct iio_scan_el *el = NULL;
147 int ret, len = 0, i = 0;
148 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
149 struct iio_dev *dev_info = dev_get_drvdata(dev);
152 while (dev_info->scan_el_attrs->attrs[i]) {
153 el = to_iio_scan_el((struct device_attribute *)
154 (dev_info->scan_el_attrs->attrs[i]));
155 /* label is in fact the address */
156 if (el->label == this_attr->address)
160 if (!dev_info->scan_el_attrs->attrs[i]) {
164 /* If this element is in the scan mask */
165 ret = iio_scan_mask_query(dev_info, el->number);
169 data = kmalloc(dev_info->ring->access.get_bpd(dev_info->ring),
173 ret = dev_info->ring->access.read_last(dev_info->ring,
176 goto error_free_data;
181 len = iio_scan_mask_count_to_right(dev_info, el->number);
184 goto error_free_data;
186 len = sprintf(buf, "ring %d\n", data[len]);
190 return ret ? ret : len;
194 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 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");
292 /* whilst trigger specific, if this read does nto occur the data
293 ready interrupt will not be cleared. Need to add a mechanism
294 to provide a dummy read function if this is not triggering on
295 the data ready function but something else is.
299 if (st->indio_dev->scan_count)
300 if (lis3l02dq_read_all(st, rx_array) >= 0)
301 for (; i < st->indio_dev->scan_count; i++)
302 data[i] = combine_8_to_16(rx_array[i*4+1],
304 /* Guaranteed to be aligned with 8 byte boundary */
305 if (st->indio_dev->scan_timestamp)
306 *((s64 *)(data + ((i + 3)/4)*4)) = st->last_timestamp;
308 st->indio_dev->ring->access.store_to(st->indio_dev->ring,
312 iio_trigger_notify_done(st->indio_dev->trig);
318 /* in these circumstances is it better to go with unaligned packing and
319 * deal with the cost?*/
320 static int lis3l02dq_data_rdy_ring_preenable(struct iio_dev *indio_dev)
323 /* Check if there are any scan elements enabled, if not fail*/
324 if (!(indio_dev->scan_count || indio_dev->scan_timestamp))
327 if (indio_dev->ring->access.set_bpd) {
328 if (indio_dev->scan_timestamp)
329 if (indio_dev->scan_count) /* Timestamp and data */
330 size = 2*sizeof(s64);
331 else /* Timestamp only */
334 size = indio_dev->scan_count*sizeof(s16);
335 indio_dev->ring->access.set_bpd(indio_dev->ring, size);
341 static int lis3l02dq_data_rdy_ring_postenable(struct iio_dev *indio_dev)
343 return indio_dev->trig
344 ? iio_trigger_attach_poll_func(indio_dev->trig,
349 static int lis3l02dq_data_rdy_ring_predisable(struct iio_dev *indio_dev)
351 return indio_dev->trig
352 ? iio_trigger_dettach_poll_func(indio_dev->trig,
358 /* Caller responsible for locking as necessary. */
359 static int __lis3l02dq_write_data_ready_config(struct device *dev,
361 iio_event_handler_list *list,
367 struct iio_dev *indio_dev = dev_get_drvdata(dev);
369 /* Get the current event mask register */
370 ret = lis3l02dq_spi_read_reg_8(dev,
371 LIS3L02DQ_REG_CTRL_2_ADDR,
375 /* Find out if data ready is already on */
377 = valold & LIS3L02DQ_REG_CTRL_2_ENABLE_DATA_READY_GENERATION;
379 /* Disable requested */
380 if (!state && currentlyset) {
382 valold &= ~LIS3L02DQ_REG_CTRL_2_ENABLE_DATA_READY_GENERATION;
383 /* The double write is to overcome a hardware bug?*/
384 ret = lis3l02dq_spi_write_reg_8(dev,
385 LIS3L02DQ_REG_CTRL_2_ADDR,
389 ret = lis3l02dq_spi_write_reg_8(dev,
390 LIS3L02DQ_REG_CTRL_2_ADDR,
395 iio_remove_event_from_list(list,
396 &indio_dev->interrupts[0]
399 /* Enable requested */
400 } else if (state && !currentlyset) {
401 /* if not set, enable requested */
402 valold |= LIS3L02DQ_REG_CTRL_2_ENABLE_DATA_READY_GENERATION;
403 iio_add_event_to_list(list, &indio_dev->interrupts[0]->ev_list);
404 ret = lis3l02dq_spi_write_reg_8(dev,
405 LIS3L02DQ_REG_CTRL_2_ADDR,
417 * lis3l02dq_data_rdy_trigger_set_state() set datardy interrupt state
419 * If disabling the interrupt also does a final read to ensure it is clear.
420 * This is only important in some cases where the scan enable elements are
421 * switched before the ring is reenabled.
423 static int lis3l02dq_data_rdy_trigger_set_state(struct iio_trigger *trig,
426 struct lis3l02dq_state *st = trig->private_data;
429 __lis3l02dq_write_data_ready_config(&st->indio_dev->dev,
430 &iio_event_data_rdy_trig,
432 if (state == false) {
433 /* possible quirk with handler currently worked around
434 by ensuring the work queue is empty */
435 flush_scheduled_work();
436 /* Clear any outstanding ready events */
437 ret = lis3l02dq_read_all(st, NULL);
439 lis3l02dq_spi_read_reg_8(&st->indio_dev->dev,
440 LIS3L02DQ_REG_WAKE_UP_SRC_ADDR,
444 DEVICE_ATTR(name, S_IRUGO, iio_trigger_read_name, NULL);
446 static struct attribute *lis3l02dq_trigger_attrs[] = {
451 static const struct attribute_group lis3l02dq_trigger_attr_group = {
452 .attrs = lis3l02dq_trigger_attrs,
456 * lis3l02dq_trig_try_reen() try renabling irq for data rdy trigger
457 * @trig: the datardy trigger
459 * As the trigger may occur on any data element being updated it is
460 * really rather likely to occur during the read from the previous
461 * trigger event. The only way to discover if this has occured on
462 * boards not supporting level interrupts is to take a look at the line.
463 * If it is indicating another interrupt and we don't seem to have a
464 * handler looking at it, then we need to notify the core that we need
465 * to tell the triggering core to try reading all these again.
467 static int lis3l02dq_trig_try_reen(struct iio_trigger *trig)
469 struct lis3l02dq_state *st = trig->private_data;
470 enable_irq(st->us->irq);
471 /* If gpio still high (or high again) */
472 if (gpio_get_value(irq_to_gpio(st->us->irq)))
473 if (st->inter == 0) {
474 /* already interrupt handler dealing with it */
475 disable_irq_nosync(st->us->irq);
476 if (st->inter == 1) {
477 /* interrupt handler snuck in between test
479 enable_irq(st->us->irq);
484 /* irq reenabled so success! */
488 int lis3l02dq_probe_trigger(struct iio_dev *indio_dev)
491 struct lis3l02dq_state *state = indio_dev->dev_data;
493 state->trig = iio_allocate_trigger();
494 state->trig->name = kmalloc(IIO_TRIGGER_NAME_LENGTH, GFP_KERNEL);
495 if (!state->trig->name) {
497 goto error_free_trig;
499 snprintf((char *)state->trig->name,
500 IIO_TRIGGER_NAME_LENGTH,
501 "lis3l02dq-dev%d", indio_dev->id);
502 state->trig->dev.parent = &state->us->dev;
503 state->trig->owner = THIS_MODULE;
504 state->trig->private_data = state;
505 state->trig->set_trigger_state = &lis3l02dq_data_rdy_trigger_set_state;
506 state->trig->try_reenable = &lis3l02dq_trig_try_reen;
507 state->trig->control_attrs = &lis3l02dq_trigger_attr_group;
508 ret = iio_trigger_register(state->trig);
510 goto error_free_trig_name;
514 error_free_trig_name:
515 kfree(state->trig->name);
517 iio_free_trigger(state->trig);
522 void lis3l02dq_remove_trigger(struct iio_dev *indio_dev)
524 struct lis3l02dq_state *state = indio_dev->dev_data;
526 iio_trigger_unregister(state->trig);
527 kfree(state->trig->name);
528 iio_free_trigger(state->trig);
531 void lis3l02dq_unconfigure_ring(struct iio_dev *indio_dev)
533 kfree(indio_dev->pollfunc);
534 iio_sw_rb_free(indio_dev->ring);
537 int lis3l02dq_configure_ring(struct iio_dev *indio_dev)
540 struct lis3l02dq_state *st = indio_dev->dev_data;
541 struct iio_ring_buffer *ring;
542 INIT_WORK(&st->work_trigger_to_ring, lis3l02dq_trigger_bh_to_ring);
543 /* Set default scan mode */
545 iio_scan_mask_set(indio_dev, iio_scan_el_accel_x.number);
546 iio_scan_mask_set(indio_dev, iio_scan_el_accel_y.number);
547 iio_scan_mask_set(indio_dev, iio_scan_el_accel_z.number);
548 indio_dev->scan_timestamp = true;
550 indio_dev->scan_el_attrs = &lis3l02dq_scan_el_group;
552 ring = iio_sw_rb_allocate(indio_dev);
557 indio_dev->ring = ring;
558 /* Effectively select the ring buffer implementation */
559 iio_ring_sw_register_funcs(&ring->access);
560 ring->preenable = &lis3l02dq_data_rdy_ring_preenable;
561 ring->postenable = &lis3l02dq_data_rdy_ring_postenable;
562 ring->predisable = &lis3l02dq_data_rdy_ring_predisable;
563 ring->owner = THIS_MODULE;
565 indio_dev->pollfunc = kzalloc(sizeof(*indio_dev->pollfunc), GFP_KERNEL);
566 if (indio_dev->pollfunc == NULL) {
568 goto error_iio_sw_rb_free;;
570 indio_dev->pollfunc->poll_func_main = &lis3l02dq_poll_func_th;
571 indio_dev->pollfunc->private_data = indio_dev;
572 indio_dev->modes |= INDIO_RING_TRIGGERED;
575 error_iio_sw_rb_free:
576 iio_sw_rb_free(indio_dev->ring);
580 int lis3l02dq_initialize_ring(struct iio_ring_buffer *ring)
582 return iio_ring_buffer_register(ring);
585 void lis3l02dq_uninitialize_ring(struct iio_ring_buffer *ring)
587 iio_ring_buffer_unregister(ring);
591 int lis3l02dq_set_ring_length(struct iio_dev *indio_dev, int length)
593 /* Set sensible defaults for the ring buffer */
594 if (indio_dev->ring->access.set_length)
595 return indio_dev->ring->access.set_length(indio_dev->ring, 500);