chiark / gitweb /
import udev repository
[elogind.git] / src / udev / src / accelerometer / accelerometer.c
diff --git a/src/udev/src/accelerometer/accelerometer.c b/src/udev/src/accelerometer/accelerometer.c
new file mode 100644 (file)
index 0000000..bc9715b
--- /dev/null
@@ -0,0 +1,357 @@
+/*
+ * 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 keymap; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#include <stdio.h>
+#include <string.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 (strcmp (orientation, orientations[i]) == 0)
+                        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 = 1; } }
+
+/* accelerometers */
+static void test_orientation(struct udev *udev,
+                             struct udev_device *dev,
+                             const char *devpath)
+{
+        OrientationUp old, new;
+        int fd, r;
+        struct input_event ev[64];
+        int got_syn = 0;
+        int got_x, got_y, got_z;
+        int x = 0, y = 0, z = 0;
+        char text[64];
+
+        old = get_prev_orientation(dev);
+
+        if ((fd = open(devpath, O_RDONLY)) < 0)
+                return;
+
+        got_x = got_y = got_z = 0;
+
+        while (1) {
+                int i;
+
+                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 == 1) {
+                                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 = 1;
+                        }
+                        if (got_x && got_y && got_z)
+                                goto read_dev;
+                }
+        }
+
+read_dev:
+        close(fd);
+
+        if (!got_x || !got_y || !got_z)
+                return;
+
+        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;
+        const char *id_path;
+        struct udev_enumerate *enumerate;
+        struct udev_list_entry *list_entry;
+
+        udev = udev_new();
+        if (udev == NULL)
+                return 1;
+
+        udev_log_init("input_id");
+        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;
+                        if (udev_get_log_priority(udev) < LOG_INFO)
+                                udev_set_log_priority(udev, LOG_INFO);
+                        break;
+                case 'h':
+                        help();
+                        exit(0);
+                default:
+                        exit(1);
+                }
+        }
+
+        if (argv[optind] == NULL) {
+                help();
+                exit(1);
+        }
+
+        /* get the device */
+        snprintf(devpath, sizeof(devpath), "%s/%s", udev_get_sys_path(udev), argv[optind]);
+        dev = udev_device_new_from_syspath(udev, devpath);
+        if (dev == NULL) {
+                fprintf(stderr, "unable to access '%s'\n", devpath);
+                return 1;
+        }
+
+        id_path = udev_device_get_property_value(dev, "ID_PATH");
+        if (id_path == NULL) {
+                fprintf (stderr, "unable to get property ID_PATH for '%s'", devpath);
+                return 0;
+        }
+
+        /* Get the children devices and find the devnode
+         * FIXME: use udev_enumerate_add_match_children() instead
+         * when it's available */
+        devnode = NULL;
+        enumerate = udev_enumerate_new(udev);
+        udev_enumerate_add_match_property(enumerate, "ID_PATH", id_path);
+        udev_enumerate_add_match_subsystem(enumerate, "input");
+        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;
+        }
+
+        info(udev, "Opening accelerometer device %s\n", devnode);
+        test_orientation(udev, dev, devnode);
+        free(devnode);
+
+        return 0;
+}