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Diffstat (limited to 'src/udev/accelerometer/accelerometer.c')
-rw-r--r--src/udev/accelerometer/accelerometer.c342
1 files changed, 342 insertions, 0 deletions
diff --git a/src/udev/accelerometer/accelerometer.c b/src/udev/accelerometer/accelerometer.c
new file mode 100644
index 0000000000..e611b48a42
--- /dev/null
+++ b/src/udev/accelerometer/accelerometer.c
@@ -0,0 +1,342 @@
+/*
+ * accelerometer - exports device orientation through property
+ *
+ * When an "change" event is received on an accelerometer,
+ * open its device node, and from the value, as well as the previous
+ * value of the property, calculate the device's new orientation,
+ * and export it as ID_INPUT_ACCELEROMETER_ORIENTATION.
+ *
+ * Possible values are:
+ * undefined
+ * * normal
+ * * bottom-up
+ * * left-up
+ * * right-up
+ *
+ * The property will be persistent across sessions, and the new
+ * orientations can be deducted from the previous one (it allows
+ * for a threshold for switching between opposite ends of the
+ * orientation).
+ *
+ * Copyright (C) 2011 Red Hat, Inc.
+ * Author:
+ * Bastien Nocera <hadess@hadess.net>
+ *
+ * orientation_calc() from the sensorfw package
+ * Copyright (C) 2009-2010 Nokia Corporation
+ * Authors:
+ * Üstün Ergenoglu <ext-ustun.ergenoglu@nokia.com>
+ * Timo Rongas <ext-timo.2.rongas@nokia.com>
+ * Lihan Guo <lihan.guo@digia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdbool.h>
+#include <math.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <getopt.h>
+#include <limits.h>
+#include <linux/limits.h>
+#include <linux/input.h>
+
+#include "libudev.h"
+#include "libudev-private.h"
+
+/* we must use this kernel-compatible implementation */
+#define BITS_PER_LONG (sizeof(unsigned long) * 8)
+#define NBITS(x) ((((x)-1)/BITS_PER_LONG)+1)
+#define OFF(x) ((x)%BITS_PER_LONG)
+#define BIT(x) (1UL<<OFF(x))
+#define LONG(x) ((x)/BITS_PER_LONG)
+#define test_bit(bit, array) ((array[LONG(bit)] >> OFF(bit)) & 1)
+
+static int debug = 0;
+
+static void log_fn(struct udev *udev, int priority,
+ const char *file, int line, const char *fn,
+ const char *format, va_list args)
+{
+ if (debug) {
+ fprintf(stderr, "%s: ", fn);
+ vfprintf(stderr, format, args);
+ } else {
+ vsyslog(priority, format, args);
+ }
+}
+
+typedef enum {
+ ORIENTATION_UNDEFINED,
+ ORIENTATION_NORMAL,
+ ORIENTATION_BOTTOM_UP,
+ ORIENTATION_LEFT_UP,
+ ORIENTATION_RIGHT_UP
+} OrientationUp;
+
+static const char *orientations[] = {
+ "undefined",
+ "normal",
+ "bottom-up",
+ "left-up",
+ "right-up",
+ NULL
+};
+
+#define ORIENTATION_UP_UP ORIENTATION_NORMAL
+
+#define DEFAULT_THRESHOLD 250
+#define RADIANS_TO_DEGREES 180.0/M_PI
+#define SAME_AXIS_LIMIT 5
+
+#define THRESHOLD_LANDSCAPE 25
+#define THRESHOLD_PORTRAIT 20
+
+static const char *
+orientation_to_string (OrientationUp o)
+{
+ return orientations[o];
+}
+
+static OrientationUp
+string_to_orientation (const char *orientation)
+{
+ int i;
+
+ if (orientation == NULL)
+ return ORIENTATION_UNDEFINED;
+ for (i = 0; orientations[i] != NULL; i++) {
+ if (streq (orientation, orientations[i]))
+ return i;
+ }
+ return ORIENTATION_UNDEFINED;
+}
+
+static OrientationUp
+orientation_calc (OrientationUp prev,
+ int x, int y, int z)
+{
+ int rotation;
+ OrientationUp ret = prev;
+
+ /* Portrait check */
+ rotation = round(atan((double) x / sqrt(y * y + z * z)) * RADIANS_TO_DEGREES);
+
+ if (abs(rotation) > THRESHOLD_PORTRAIT) {
+ ret = (rotation < 0) ? ORIENTATION_LEFT_UP : ORIENTATION_RIGHT_UP;
+
+ /* Some threshold to switching between portrait modes */
+ if (prev == ORIENTATION_LEFT_UP || prev == ORIENTATION_RIGHT_UP) {
+ if (abs(rotation) < SAME_AXIS_LIMIT) {
+ ret = prev;
+ }
+ }
+
+ } else {
+ /* Landscape check */
+ rotation = round(atan((double) y / sqrt(x * x + z * z)) * RADIANS_TO_DEGREES);
+
+ if (abs(rotation) > THRESHOLD_LANDSCAPE) {
+ ret = (rotation < 0) ? ORIENTATION_BOTTOM_UP : ORIENTATION_NORMAL;
+
+ /* Some threshold to switching between landscape modes */
+ if (prev == ORIENTATION_BOTTOM_UP || prev == ORIENTATION_NORMAL) {
+ if (abs(rotation) < SAME_AXIS_LIMIT) {
+ ret = prev;
+ }
+ }
+ }
+ }
+
+ return ret;
+}
+
+static OrientationUp
+get_prev_orientation(struct udev_device *dev)
+{
+ const char *value;
+
+ value = udev_device_get_property_value(dev, "ID_INPUT_ACCELEROMETER_ORIENTATION");
+ if (value == NULL)
+ return ORIENTATION_UNDEFINED;
+ return string_to_orientation(value);
+}
+
+#define SET_AXIS(axis, code_) if (ev[i].code == code_) { if (got_##axis == 0) { axis = ev[i].value; got_##axis = true; } }
+
+/* accelerometers */
+static void test_orientation(struct udev *udev,
+ struct udev_device *dev,
+ const char *devpath)
+{
+ OrientationUp old, new;
+ _cleanup_close_ int fd = -1;
+ struct input_event ev[64];
+ bool got_syn = false;
+ bool got_x = false, got_y = false, got_z = false;
+ int x = 0, y = 0, z = 0;
+ char text[64];
+
+ old = get_prev_orientation(dev);
+
+ fd = open(devpath, O_RDONLY);
+ if (fd < 0)
+ return;
+
+ while (1) {
+ int i, r;
+
+ r = read(fd, ev, sizeof(struct input_event) * 64);
+
+ if (r < (int) sizeof(struct input_event))
+ return;
+
+ for (i = 0; i < r / (int) sizeof(struct input_event); i++) {
+ if (got_syn) {
+ if (ev[i].type == EV_ABS) {
+ SET_AXIS(x, ABS_X);
+ SET_AXIS(y, ABS_Y);
+ SET_AXIS(z, ABS_Z);
+ }
+ }
+ if (ev[i].type == EV_SYN && ev[i].code == SYN_REPORT)
+ got_syn = true;
+ if (got_x && got_y && got_z)
+ goto read_dev;
+ }
+ }
+
+read_dev:
+ new = orientation_calc(old, x, y, z);
+ snprintf(text, sizeof(text),
+ "ID_INPUT_ACCELEROMETER_ORIENTATION=%s", orientation_to_string(new));
+ puts(text);
+}
+
+static void help(void)
+{
+ printf("Usage: accelerometer [options] <device path>\n"
+ " --debug debug to stderr\n"
+ " --help print this help text\n\n");
+}
+
+int main (int argc, char** argv)
+{
+ struct udev *udev;
+ struct udev_device *dev;
+
+ static const struct option options[] = {
+ { "debug", no_argument, NULL, 'd' },
+ { "help", no_argument, NULL, 'h' },
+ {}
+ };
+
+ char devpath[PATH_MAX];
+ char *devnode;
+ struct udev_enumerate *enumerate;
+ struct udev_list_entry *list_entry;
+
+ udev = udev_new();
+ if (udev == NULL)
+ return 1;
+
+ log_open();
+ udev_set_log_fn(udev, log_fn);
+
+ /* CLI argument parsing */
+ while (1) {
+ int option;
+
+ option = getopt_long(argc, argv, "dxh", options, NULL);
+ if (option == -1)
+ break;
+
+ switch (option) {
+ case 'd':
+ debug = 1;
+ log_set_max_level(LOG_DEBUG);
+ udev_set_log_priority(udev, LOG_DEBUG);
+ break;
+ case 'h':
+ help();
+ exit(0);
+ default:
+ exit(1);
+ }
+ }
+
+ if (argv[optind] == NULL) {
+ help();
+ exit(1);
+ }
+
+ /* get the device */
+ snprintf(devpath, sizeof(devpath), "/sys/%s", argv[optind]);
+ dev = udev_device_new_from_syspath(udev, devpath);
+ if (dev == NULL) {
+ fprintf(stderr, "unable to access '%s'\n", devpath);
+ return 1;
+ }
+
+ /* Get the children devices and find the devnode */
+ devnode = NULL;
+ enumerate = udev_enumerate_new(udev);
+ udev_enumerate_add_match_parent(enumerate, dev);
+ udev_enumerate_scan_devices(enumerate);
+ udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(enumerate)) {
+ struct udev_device *device;
+ const char *node;
+
+ device = udev_device_new_from_syspath(udev_enumerate_get_udev(enumerate),
+ udev_list_entry_get_name(list_entry));
+ if (device == NULL)
+ continue;
+ /* Already found it */
+ if (devnode != NULL) {
+ udev_device_unref(device);
+ continue;
+ }
+
+ node = udev_device_get_devnode(device);
+ if (node == NULL) {
+ udev_device_unref(device);
+ continue;
+ }
+ /* Use the event sub-device */
+ if (strstr(node, "/event") == NULL) {
+ udev_device_unref(device);
+ continue;
+ }
+
+ devnode = strdup(node);
+ udev_device_unref(device);
+ }
+
+ if (devnode == NULL) {
+ fprintf(stderr, "unable to get device node for '%s'\n", devpath);
+ return 0;
+ }
+
+ log_debug("opening accelerometer device %s\n", devnode);
+ test_orientation(udev, dev, devnode);
+ free(devnode);
+ log_close();
+ return 0;
+}
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