twin: add Linux joystick support

Add a simple event layer for joystick devices.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

5 files changed, 204 insertions, 0 deletions

diff --git a/Makefile.am b/Makefile.am
index 3a471ff..10144a0 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -56,6 +56,11 @@ pkginclude_HEADERS += libtwin/twin_linux_mouse.h
 libtwin_libtwin_la_SOURCES += libtwin/twin_linux_mouse.c
 endif
 
+if TWIN_JOYSTICK
+pkginclude_HEADERS += libtwin/twin_linux_js.h
+libtwin_libtwin_la_SOURCES += libtwin/twin_linux_js.c
+endif
+
 if TWIN_PNG
 pkginclude_HEADERS += libtwin/twin_png.h
 libtwin_libtwin_la_SOURCES += libtwin/twin_png.c
diff --git a/configure.ac b/configure.ac
index 5552694..024e93c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -81,6 +81,12 @@ AC_ARG_ENABLE(linux-mouse,
 		[Disable linux mouse support (default=enabled)]),
 	twin_mouse="$enableval", twin_mouse="yes")
 
+# linux joystick
+AC_ARG_ENABLE(linux-joystick,
+	AC_HELP_STRING([--disable-linux-joystick],
+		[Disable linux joystick support (default=enabled)]),
+	twin_joystick="$enableval", twin_joystick="yes")
+
 # zlib
 AC_ARG_ENABLE(zlib,
 	AC_HELP_STRING([--disable-zlib],
@@ -186,6 +192,7 @@ AM_CONDITIONAL(TWIN_PNG, test x$twin_png = xyes)
 AM_CONDITIONAL(TWIN_JPEG, test x$twin_jpeg = xyes)
 AM_CONDITIONAL(TWIN_TTF, test x$twin_ttf = xyes)
 AM_CONDITIONAL(TWIN_MOUSE, test x$twin_mouse = xyes)
+AM_CONDITIONAL(TWIN_JOYSTICK, test x$twin_joystick = xyes)
 
 AC_MSG_NOTICE([x11 support:    $twin_x11])
 AC_MSG_NOTICE([fbdev support:  $twin_fb])
@@ -194,6 +201,7 @@ AC_MSG_NOTICE([png support:    $twin_png])
 AC_MSG_NOTICE([jpeg support:   $twin_jpeg])
 AC_MSG_NOTICE([twin_ttf tool:  $twin_ttf])
 AC_MSG_NOTICE([linux mouse:    $twin_mouse])
+AC_MSG_NOTICE([linux joystick: $twin_joystick])
 AC_MSG_NOTICE([altivec:        $twin_altivec])
 
 AC_OUTPUT([Makefile
diff --git a/libtwin/twin.h b/libtwin/twin.h
index 04a9ac6..1114bc5 100644
--- a/libtwin/twin.h
+++ b/libtwin/twin.h
@@ -35,6 +35,8 @@ typedef int16_t	    twin_coord_t;
 typedef int16_t	    twin_style_t;
 typedef int16_t	    twin_count_t;
 typedef int16_t	    twin_keysym_t;
+typedef uint8_t	    twin_js_number_t;
+typedef int16_t	    twin_js_value_t;
 typedef int32_t	    twin_area_t;
 typedef int32_t	    twin_time_t;
 typedef int16_t	    twin_stretch_t;
@@ -120,6 +122,10 @@ typedef enum _twin_event_kind {
     TwinEventActivate		= 0x0201,
     TwinEventDeactivate		= 0x0202,
 
+    /* Joystick */
+    TwinEventJoyButton		= 0x0401,
+    TwinEventJoyAxis		= 0x0402,
+
     /* Widgets */
     TwinEventPaint		= 0x1001,
     TwinEventQueryGeometry	= 0x1002,
@@ -139,6 +145,10 @@ typedef struct _twin_event {
 	    twin_keysym_t   key;
 	} key;
 	struct {
+	    twin_js_number_t control;
+	    twin_js_value_t  value;
+	} js;
+	struct {
 	    twin_ucs4_t	    ucs4;
 	} ucs4;
 	struct {
diff --git a/libtwin/twin_linux_js.c b/libtwin/twin_linux_js.c
new file mode 100644
index 0000000..3108cb8
--- /dev/null
+++ b/libtwin/twin_linux_js.c
@@ -0,0 +1,144 @@
+/*
+ * Linux joystick driver for Twin
+ *
+ * Copyright 2007 Jeremy Kerr <jk@ozlabs.org>
+ *
+ * This Library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This Library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with the Twin Library; see the file COPYING.  If not,
+ * write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include <dirent.h>
+#include <linux/joystick.h>
+
+#include "twin.h"
+#include "twin_linux_js.h"
+
+#define DEBUG(fmt...)	printf(fmt)
+
+struct twin_js_dev {
+	int fd;
+	twin_screen_t *screen;
+};
+
+static twin_bool_t twin_linux_js_events(int file, twin_file_op_t ops,
+					   void *closure)
+{
+	struct twin_js_dev *js = closure;
+	struct js_event js_event;
+	int rc;
+	twin_event_t tev;
+
+	for (;;) {
+
+		rc = read(js->fd, &js_event, sizeof(js_event));
+		if (rc < 0 && errno == EAGAIN)
+			break;
+
+		if (rc < 0) {
+			DEBUG("Error reading from joystick device: %s\n",
+					strerror(errno));
+			return TWIN_FALSE;
+		}
+
+		if (rc != sizeof(js_event))
+			break;
+
+		if (js_event.type == JS_EVENT_BUTTON)
+			tev.kind = TwinEventJoyButton;
+		else if (js_event.type == JS_EVENT_AXIS)
+			tev.kind = TwinEventJoyAxis;
+		else
+			continue;
+
+		tev.u.js.control = js_event.number;
+		tev.u.js.value = js_event.value;
+		twin_screen_dispatch(js->screen, &tev);
+	}
+
+	return TWIN_TRUE;
+}
+
+
+static int nr_devs;
+struct twin_js_dev *js_devs;
+
+int twin_linux_js_create(twin_screen_t *screen)
+{
+	struct dirent *dirent;
+	DIR *dir;
+
+	dir = opendir("/dev/input");
+	if (dir == NULL) {
+		perror("opendir(/dev/input)");
+		return -1;
+	}
+
+	while ((dirent = readdir(dir))) {
+		/* buffer to hold dir.d_name, plus "/dev/input/" */
+		char dev_name[sizeof(dirent->d_name) + 12];
+		int dev_fd;
+		struct twin_js_dev *js_dev, *tmp;
+
+
+		if (strncmp(dirent->d_name, "js", 2))
+			continue;
+
+		strcpy(dev_name, "/dev/input/");
+		strcat(dev_name, dirent->d_name);
+
+		dev_fd = open(dev_name, O_RDONLY | O_NONBLOCK);
+		if (dev_fd < 0) {
+			perror("open");
+			continue;
+		}
+		DEBUG("Adding joystick device %s\n", dev_name);
+
+		tmp = realloc(js_devs, ++nr_devs * sizeof(*js_devs));
+		if (!tmp) {
+			close(dev_fd);
+			continue;
+		}
+		js_devs = tmp;
+
+		js_dev = js_devs + nr_devs - 1;
+		js_dev->fd = dev_fd;
+		js_dev->screen = screen;
+
+		twin_set_file(twin_linux_js_events, dev_fd, TWIN_READ, js_dev);
+	}
+	closedir(dir);
+
+	return 0;
+}
+
+void twin_linux_js_destroy()
+{
+	int i;
+
+	for (i = 0; i < nr_devs; i++)
+		close(js_devs[i].fd);
+
+	free(js_devs);
+	js_devs = NULL;
+}
+
diff --git a/libtwin/twin_linux_js.h b/libtwin/twin_linux_js.h
new file mode 100644
index 0000000..0fa301d
--- /dev/null
+++ b/libtwin/twin_linux_js.h
@@ -0,0 +1,37 @@
+/*
+ * Linux joystick driver for Twin
+ *
+ * Copyright 2007 Jeremy Kerr <jk@ozlabs.org>
+ *
+ * This Library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This Library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with the Twin Library; see the file COPYING.  If not,
+ * write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+#ifndef _TWIN_LINUX_JS_H_
+#define _TWIN_LINUX_JS_H_
+
+#include <libtwin/twin.h>
+
+/**
+ * twin_linux_js_create - create the linux joystick driver
+ * @file: device file to open, pass NULL for default
+ */
+int twin_linux_js_create(twin_screen_t *screen);
+
+/**
+ * twin_linux_js_destroy - destroy the linux js driver
+ */
+void twin_linux_js_destroy(void);
+
+#endif /* _TWIN_LINUX_JS_H_ */