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-rw-r--r--drivers/staging/iio/Documentation/device.txt2
-rw-r--r--drivers/staging/iio/Documentation/iio_event_monitor.c241
-rw-r--r--drivers/staging/iio/Documentation/inkernel.txt58
3 files changed, 300 insertions, 1 deletions
diff --git a/drivers/staging/iio/Documentation/device.txt b/drivers/staging/iio/Documentation/device.txt
index 1abb80c..8926f24 100644
--- a/drivers/staging/iio/Documentation/device.txt
+++ b/drivers/staging/iio/Documentation/device.txt
@@ -62,7 +62,7 @@ Then fill in the following:
An optional associated buffer.
- indio_dev->pollfunc:
Poll function related elements. This controls what occurs when a trigger
- to which this device is attached sends and event.
+ to which this device is attached sends an event.
- indio_dev->channels:
Specification of device channels. Most attributes etc are built
form this spec.
diff --git a/drivers/staging/iio/Documentation/iio_event_monitor.c b/drivers/staging/iio/Documentation/iio_event_monitor.c
new file mode 100644
index 0000000..0d21a27
--- /dev/null
+++ b/drivers/staging/iio/Documentation/iio_event_monitor.c
@@ -0,0 +1,241 @@
+/* Industrialio event test code.
+ *
+ * Copyright (c) 2011-2012 Lars-Peter Clausen <lars@metafoo.de>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is primarily intended as an example application.
+ * Reads the current buffer setup from sysfs and starts a short capture
+ * from the specified device, pretty printing the result after appropriate
+ * conversion.
+ *
+ * Usage:
+ * iio_event_monitor <device_name>
+ *
+ */
+
+#define _GNU_SOURCE
+
+#include <unistd.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <poll.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include "iio_utils.h"
+#include "../events.h"
+
+static const char * const iio_chan_type_name_spec[] = {
+ [IIO_VOLTAGE] = "voltage",
+ [IIO_CURRENT] = "current",
+ [IIO_POWER] = "power",
+ [IIO_ACCEL] = "accel",
+ [IIO_ANGL_VEL] = "anglvel",
+ [IIO_MAGN] = "magn",
+ [IIO_LIGHT] = "illuminance",
+ [IIO_INTENSITY] = "intensity",
+ [IIO_PROXIMITY] = "proximity",
+ [IIO_TEMP] = "temp",
+ [IIO_INCLI] = "incli",
+ [IIO_ROT] = "rot",
+ [IIO_ANGL] = "angl",
+ [IIO_TIMESTAMP] = "timestamp",
+ [IIO_CAPACITANCE] = "capacitance",
+};
+
+static const char * const iio_ev_type_text[] = {
+ [IIO_EV_TYPE_THRESH] = "thresh",
+ [IIO_EV_TYPE_MAG] = "mag",
+ [IIO_EV_TYPE_ROC] = "roc",
+ [IIO_EV_TYPE_THRESH_ADAPTIVE] = "thresh_adaptive",
+ [IIO_EV_TYPE_MAG_ADAPTIVE] = "mag_adaptive",
+};
+
+static const char * const iio_ev_dir_text[] = {
+ [IIO_EV_DIR_EITHER] = "either",
+ [IIO_EV_DIR_RISING] = "rising",
+ [IIO_EV_DIR_FALLING] = "falling"
+};
+
+static const char * const iio_modifier_names[] = {
+ [IIO_MOD_X] = "x",
+ [IIO_MOD_Y] = "y",
+ [IIO_MOD_Z] = "z",
+ [IIO_MOD_LIGHT_BOTH] = "both",
+ [IIO_MOD_LIGHT_IR] = "ir",
+};
+
+static bool event_is_known(struct iio_event_data *event)
+{
+ enum iio_chan_type type = IIO_EVENT_CODE_EXTRACT_CHAN_TYPE(event->id);
+ enum iio_modifier mod = IIO_EVENT_CODE_EXTRACT_MODIFIER(event->id);
+ enum iio_event_type ev_type = IIO_EVENT_CODE_EXTRACT_TYPE(event->id);
+ enum iio_event_direction dir = IIO_EVENT_CODE_EXTRACT_DIR(event->id);
+
+ switch (type) {
+ case IIO_VOLTAGE:
+ case IIO_CURRENT:
+ case IIO_POWER:
+ case IIO_ACCEL:
+ case IIO_ANGL_VEL:
+ case IIO_MAGN:
+ case IIO_LIGHT:
+ case IIO_INTENSITY:
+ case IIO_PROXIMITY:
+ case IIO_TEMP:
+ case IIO_INCLI:
+ case IIO_ROT:
+ case IIO_ANGL:
+ case IIO_TIMESTAMP:
+ case IIO_CAPACITANCE:
+ break;
+ default:
+ return false;
+ }
+
+ switch (mod) {
+ case IIO_NO_MOD:
+ case IIO_MOD_X:
+ case IIO_MOD_Y:
+ case IIO_MOD_Z:
+ case IIO_MOD_LIGHT_BOTH:
+ case IIO_MOD_LIGHT_IR:
+ break;
+ default:
+ return false;
+ }
+
+ switch (ev_type) {
+ case IIO_EV_TYPE_THRESH:
+ case IIO_EV_TYPE_MAG:
+ case IIO_EV_TYPE_ROC:
+ case IIO_EV_TYPE_THRESH_ADAPTIVE:
+ case IIO_EV_TYPE_MAG_ADAPTIVE:
+ break;
+ default:
+ return false;
+ }
+
+ switch (dir) {
+ case IIO_EV_DIR_EITHER:
+ case IIO_EV_DIR_RISING:
+ case IIO_EV_DIR_FALLING:
+ break;
+ default:
+ return false;
+ }
+
+ return true;
+}
+
+static void print_event(struct iio_event_data *event)
+{
+ enum iio_chan_type type = IIO_EVENT_CODE_EXTRACT_CHAN_TYPE(event->id);
+ enum iio_modifier mod = IIO_EVENT_CODE_EXTRACT_MODIFIER(event->id);
+ enum iio_event_type ev_type = IIO_EVENT_CODE_EXTRACT_TYPE(event->id);
+ enum iio_event_direction dir = IIO_EVENT_CODE_EXTRACT_DIR(event->id);
+ int chan = IIO_EVENT_CODE_EXTRACT_CHAN(event->id);
+ int chan2 = IIO_EVENT_CODE_EXTRACT_CHAN2(event->id);
+ bool diff = IIO_EVENT_CODE_EXTRACT_DIFF(event->id);
+
+ if (!event_is_known(event)) {
+ printf("Unknown event: time: %lld, id: %llx\n",
+ event->timestamp, event->id);
+ return;
+ }
+
+ printf("Event: time: %lld, ", event->timestamp);
+
+ if (mod != IIO_NO_MOD) {
+ printf("type: %s(%s), ",
+ iio_chan_type_name_spec[type],
+ iio_modifier_names[mod]);
+ } else {
+ printf("type: %s, ",
+ iio_chan_type_name_spec[type]);
+ }
+
+ if (diff && chan >= 0 && chan2 >= 0)
+ printf("channel: %d-%d, ", chan, chan2);
+ else if (chan >= 0)
+ printf("channel: %d, ", chan);
+
+ printf("evtype: %s, direction: %s\n",
+ iio_ev_type_text[ev_type],
+ iio_ev_dir_text[dir]);
+}
+
+int main(int argc, char **argv)
+{
+ struct iio_event_data event;
+ const char *device_name;
+ char *chrdev_name;
+ int ret;
+ int dev_num;
+ int fd, event_fd;
+
+ if (argc <= 1) {
+ printf("Usage: %s <device_name>\n", argv[0]);
+ return -1;
+ }
+
+ device_name = argv[1];
+
+ dev_num = find_type_by_name(device_name, "iio:device");
+ if (dev_num >= 0) {
+ printf("Found IIO device with name %s with device number %d\n",
+ device_name, dev_num);
+ ret = asprintf(&chrdev_name, "/dev/iio:device%d", dev_num);
+ if (ret < 0) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+ } else {
+ /* If we can't find a IIO device by name assume device_name is a
+ IIO chrdev */
+ chrdev_name = strdup(device_name);
+ }
+
+ fd = open(chrdev_name, 0);
+ if (fd == -1) {
+ fprintf(stdout, "Failed to open %s\n", chrdev_name);
+ ret = -errno;
+ goto error_free_chrdev_name;
+ }
+
+ ret = ioctl(fd, IIO_GET_EVENT_FD_IOCTL, &event_fd);
+
+ close(fd);
+
+ if (ret == -1 || event_fd == -1) {
+ fprintf(stdout, "Failed to retrieve event fd\n");
+ ret = -errno;
+ goto error_free_chrdev_name;
+ }
+
+ while (true) {
+ ret = read(event_fd, &event, sizeof(event));
+ if (ret == -1) {
+ if (errno == EAGAIN) {
+ printf("nothing available\n");
+ continue;
+ } else {
+ perror("Failed to read event from device");
+ ret = -errno;
+ break;
+ }
+ }
+
+ print_event(&event);
+ }
+
+ close(event_fd);
+error_free_chrdev_name:
+ free(chrdev_name);
+error_ret:
+ return ret;
+}
diff --git a/drivers/staging/iio/Documentation/inkernel.txt b/drivers/staging/iio/Documentation/inkernel.txt
new file mode 100644
index 0000000..a05823e
--- /dev/null
+++ b/drivers/staging/iio/Documentation/inkernel.txt
@@ -0,0 +1,58 @@
+Industrial I/O Subsystem in kernel consumers.
+
+The IIO subsystem can act as a layer under other elements of the kernel
+providing a means of obtaining ADC type readings or of driving DAC type
+signals. The functionality supported will grow as use cases arise.
+
+Describing the channel mapping (iio/machine.h)
+
+Channel associations are described using:
+
+struct iio_map {
+ const char *adc_channel_label;
+ const char *consumer_dev_name;
+ const char *consumer_channel;
+};
+
+adc_channel_label identifies the channel on the IIO device by being
+matched against the datasheet_name field of the iio_chan_spec.
+
+consumer_dev_name allows identification of the consumer device.
+This are then used to find the channel mapping from the consumer device (see
+below).
+
+Finally consumer_channel is a string identifying the channel to the consumer.
+(Perhaps 'battery_voltage' or similar).
+
+An array of these structures is then passed to the IIO driver.
+
+Supporting in kernel interfaces in the driver (driver.h)
+
+The driver must provide datasheet_name values for its channels and
+must pass the iio_map structures and a pointer to its own iio_dev structure
+ on to the core via a call to iio_map_array_register. On removal,
+iio_map_array_unregister reverses this process.
+
+The result of this is that the IIO core now has all the information needed
+to associate a given channel with the consumer requesting it.
+
+Acting as an IIO consumer (consumer.h)
+
+The consumer first has to obtain an iio_channel structure from the core
+by calling iio_channel_get(). The correct channel is identified by:
+
+* matching dev or dev_name against consumer_dev and consumer_dev_name
+* matching consumer_channel against consumer_channel in the map
+
+There are then a number of functions that can be used to get information
+about this channel such as it's current reading.
+
+e.g.
+iio_st_read_channel_raw() - get a reading
+iio_st_read_channel_type() - get the type of channel
+
+There is also provision for retrieving all of the channels associated
+with a given consumer. This is useful for generic drivers such as
+iio_hwmon where the number and naming of channels is not known by the
+consumer driver. To do this, use iio_st_channel_get_all.
+
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