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");
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. */
360 static int __lis3l02dq_write_data_ready_config(struct device
*dev
,
362 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();
495 state
->trig
->name
= kmalloc(IIO_TRIGGER_NAME_LENGTH
, GFP_KERNEL
);
496 if (!state
->trig
->name
) {
498 goto error_free_trig
;
500 snprintf((char *)state
->trig
->name
,
501 IIO_TRIGGER_NAME_LENGTH
,
502 "lis3l02dq-dev%d", indio_dev
->id
);
503 state
->trig
->dev
.parent
= &state
->us
->dev
;
504 state
->trig
->owner
= THIS_MODULE
;
505 state
->trig
->private_data
= state
;
506 state
->trig
->set_trigger_state
= &lis3l02dq_data_rdy_trigger_set_state
;
507 state
->trig
->try_reenable
= &lis3l02dq_trig_try_reen
;
508 state
->trig
->control_attrs
= &lis3l02dq_trigger_attr_group
;
509 ret
= iio_trigger_register(state
->trig
);
511 goto error_free_trig_name
;
515 error_free_trig_name
:
516 kfree(state
->trig
->name
);
518 iio_free_trigger(state
->trig
);
523 void lis3l02dq_remove_trigger(struct iio_dev
*indio_dev
)
525 struct lis3l02dq_state
*state
= indio_dev
->dev_data
;
527 iio_trigger_unregister(state
->trig
);
528 kfree(state
->trig
->name
);
529 iio_free_trigger(state
->trig
);
532 void lis3l02dq_unconfigure_ring(struct iio_dev
*indio_dev
)
534 kfree(indio_dev
->pollfunc
);
535 iio_sw_rb_free(indio_dev
->ring
);
538 int lis3l02dq_configure_ring(struct iio_dev
*indio_dev
)
541 struct lis3l02dq_state
*st
= indio_dev
->dev_data
;
542 struct iio_ring_buffer
*ring
;
543 INIT_WORK(&st
->work_trigger_to_ring
, lis3l02dq_trigger_bh_to_ring
);
544 /* Set default scan mode */
546 iio_scan_mask_set(indio_dev
, iio_scan_el_accel_x
.number
);
547 iio_scan_mask_set(indio_dev
, iio_scan_el_accel_y
.number
);
548 iio_scan_mask_set(indio_dev
, iio_scan_el_accel_z
.number
);
549 indio_dev
->scan_timestamp
= true;
551 indio_dev
->scan_el_attrs
= &lis3l02dq_scan_el_group
;
553 ring
= iio_sw_rb_allocate(indio_dev
);
558 indio_dev
->ring
= ring
;
559 /* Effectively select the ring buffer implementation */
560 iio_ring_sw_register_funcs(&ring
->access
);
561 ring
->preenable
= &lis3l02dq_data_rdy_ring_preenable
;
562 ring
->postenable
= &lis3l02dq_data_rdy_ring_postenable
;
563 ring
->predisable
= &lis3l02dq_data_rdy_ring_predisable
;
564 ring
->owner
= THIS_MODULE
;
566 indio_dev
->pollfunc
= kzalloc(sizeof(*indio_dev
->pollfunc
), GFP_KERNEL
);
567 if (indio_dev
->pollfunc
== NULL
) {
569 goto error_iio_sw_rb_free
;;
571 indio_dev
->pollfunc
->poll_func_main
= &lis3l02dq_poll_func_th
;
572 indio_dev
->pollfunc
->private_data
= indio_dev
;
573 indio_dev
->modes
|= INDIO_RING_TRIGGERED
;
576 error_iio_sw_rb_free
:
577 iio_sw_rb_free(indio_dev
->ring
);
581 int lis3l02dq_initialize_ring(struct iio_ring_buffer
*ring
)
583 return iio_ring_buffer_register(ring
);
586 void lis3l02dq_uninitialize_ring(struct iio_ring_buffer
*ring
)
588 iio_ring_buffer_unregister(ring
);
592 int lis3l02dq_set_ring_length(struct iio_dev
*indio_dev
, int length
)
594 /* Set sensible defaults for the ring buffer */
595 if (indio_dev
->ring
->access
.set_length
)
596 return indio_dev
->ring
->access
.set_length(indio_dev
->ring
, 500);