[coreboot-gerrit] Change in em100[master]: em100: usb reset utility

[Stefan Reinauer (Code Review)]

Stefan Reinauer has uploaded this change for review. ( https://review.coreboot.org/c/em100/+/48547 )

Change subject: em100: usb reset utility
......................................................................

em100: usb reset utility

If youre EM100 hangs because of an incomplete transfer,
you can use this Linux utility to reset the USB port and
get the EM100 working again

Signed-off-by: Stefan Reinauer 
Change-Id: I5cc9c6108dff5d980c97a92a1ac4a209ea77a3ca
---
A usbreset.c
1 file changed, 38 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/em100 refs/changes/47/48547/1

diff --git a/usbreset.c b/usbreset.c
new file mode 100644
index 0000000..d0a5c07
--- /dev/null
+++ b/usbreset.c
@@ -0,0 +1,38 @@
+#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");
+        fprintf(stderr, " device-filename i.e. /dev/bus/usb/001/024\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;
+}