1 files changed, 103 insertions, 0 deletions

diff --git a/src/caps.c b/src/caps.c
new file mode 100644
index 0000000..1821bd7
--- /dev/null
+++ b/src/caps.c
@@ -0,0 +1,103 @@
+/*****************************************************************************
+ *
+ * mtdev - MT device event converter (MIT license)
+ *
+ * Copyright (C) 2010 Henrik Rydberg <rydberg@euromail.se>
+ * Copyright (C) 2010 Canonical Ltd.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ ****************************************************************************/
+
+#include "common.h"
+
+#define SETABS(c, x, map, key, fd)                                      \
+        (c->has_##x = getbit(map, key) && getabs(&c->x, key, fd))
+
+static const int SN_COORD = 250;        /* coordinate signal-to-noise ratio */
+static const int SN_WIDTH = 100;        /* width signal-to-noise ratio */
+static const int SN_ORIENT = 10;        /* orientation signal-to-noise ratio */
+
+static const int bits_per_long = 8 * sizeof(long);
+
+static inline int nlongs(int nbit)
+{
+        return (nbit + bits_per_long - 1) / bits_per_long;
+}
+
+static inline int getbit(const unsigned long *map, int key)
+{
+        return (map[key / bits_per_long] >> (key % bits_per_long)) & 0x01;
+}
+
+static int getabs(struct input_absinfo *abs, int key, int fd)
+{
+        int rc;
+        SYSCALL(rc = ioctl(fd, EVIOCGABS(key), abs));
+        return rc >= 0;
+}
+
+static int has_mt_data(const struct mtdev_caps *cap)
+{
+        return cap->has_abs[MTDEV_POSITION_X] && cap->has_abs[MTDEV_POSITION_Y];
+}
+
+static void default_fuzz(struct mtdev_caps *cap, int bit, int sn)
+{
+        if (cap->has_abs[bit] && cap->abs[bit].fuzz == 0)
+                cap->abs[bit].fuzz =
+                        (cap->abs[bit].maximum - cap->abs[bit].minimum) / sn;
+}
+
+static int read_caps(struct mtdev_caps *cap, int fd)
+{
+        unsigned long absbits[nlongs(ABS_MAX)];
+        int rc, i;
+
+        memset(cap, 0, sizeof(struct mtdev_caps));
+
+        SYSCALL(rc = ioctl(fd, EVIOCGBIT(EV_ABS, sizeof(absbits)), absbits));
+        if (rc < 0)
+                return rc;
+
+        SETABS(cap, slot, absbits, ABS_MT_SLOT, fd);
+        for (i = 0; i < MT_ABS_SIZE; i++)
+                SETABS(cap, abs[i], absbits, mtdev_mt2abs(i), fd);
+
+        cap->has_mtdata = has_mt_data(cap);
+
+        if (cap->has_abs[MTDEV_TRACKING_ID])
+                cap->nullid = cap->abs[MTDEV_TRACKING_ID].minimum - 1;
+
+        default_fuzz(cap, MTDEV_POSITION_X, SN_COORD);
+        default_fuzz(cap, MTDEV_POSITION_Y, SN_COORD);
+        default_fuzz(cap, MTDEV_TOUCH_MAJOR, SN_WIDTH);
+        default_fuzz(cap, MTDEV_TOUCH_MINOR, SN_WIDTH);
+        default_fuzz(cap, MTDEV_WIDTH_MAJOR, SN_WIDTH);
+        default_fuzz(cap, MTDEV_WIDTH_MINOR, SN_WIDTH);
+        default_fuzz(cap, MTDEV_ORIENTATION, SN_ORIENT);
+
+        return 0;
+}
+
+int mtdev_configure(struct mtdev *dev, int fd)
+{
+        return read_caps(&dev->caps, fd);
+}