add usbreset - a small simple utility to send port rests to selected usb devices (#10394)

SVN-Revision: 29611

1 files changed, 76 insertions, 0 deletions

diff --git a/package/usbreset/src/usbreset.c b/package/usbreset/src/usbreset.c
new file mode 100644
index 0000000..03d1787
--- /dev/null
+++ b/package/usbreset/src/usbreset.c
@@ -0,0 +1,76 @@
+/* usbreset -- send a USB port reset to a USB device */
+
+/*
+
+http://marc.info/?l=linux-usb-users&m=116827193506484&w=2
+
+and needs mounted usbfs filesystem
+
+	sudo mount -t usbfs none /proc/bus/usb
+
+There is a way to suspend a USB device.  In order to use it, 
+you must have a kernel with CONFIG_PM_SYSFS_DEPRECATED turned on.  To 
+suspend a device, do (as root):
+
+	echo -n 2 >/sys/bus/usb/devices/.../power/state
+
+where the "..." is the ID for your device.  To unsuspend, do the same 
+thing but with a "0" instead of the "2" above.
+
+Note that this mechanism is slated to be removed from the kernel within 
+the next year.  Hopefully some other mechanism will take its place.
+
+> To reset a
+> device?
+
+Here's a program to do it.  You invoke it as either
+
+	usbreset /proc/bus/usb/BBB/DDD
+or
+	usbreset /dev/usbB.D
+
+depending on how your system is set up, where BBB and DDD are the bus and
+device address numbers.
+
+Alan Stern
+
+*/
+
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/ioctl.h>
+
+#include <linux/usbdevice_fs.h>
+
+
+int main(int argc, char **argv)
+{
+	const char *filename;
+	int fd;
+	int rc;
+
+	if (argc != 2) {
+		fprintf(stderr, "Usage: usbreset device-filename\n");
+		return 1;
+	}
+	filename = argv[1];
+
+	fd = open(filename, O_WRONLY);
+	if (fd < 0) {
+		perror("Error opening output file");
+		return 1;
+	}
+
+	printf("Resetting USB device %s\n", filename);
+	rc = ioctl(fd, USBDEVFS_RESET, 0);
+	if (rc < 0) {
+		perror("Error in ioctl");
+		return 1;
+	}
+	printf("Reset successful\n");
+
+	close(fd);
+	return 0;
+}