USB: add Printer Gadget Driver

G_PRINTER: Adds a USB printer gadget driver for use in printer firmware.

This adds a USB printer gadget driver for use in printer firmware.
The printer gadget channels data between the USB host and a userspace
program driving the print engine. The user space program reads and
writes the device file /dev/g_printer to receive or send printer data.
It can use ioctl calls to the device file to get or set printer status.

Signed-off-by: Craig W. Nadler <craig@nadler.us>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

3 files changed, 37 insertions, 0 deletions

diff --git a/include/linux/usb/Kbuild b/include/linux/usb/Kbuild
index 6ce42bf9f74..74a9ce78e7a 100644
--- a/include/linux/usb/Kbuild
+++ b/include/linux/usb/Kbuild
@@ -3,4 +3,5 @@ unifdef-y += cdc.h
 unifdef-y += ch9.h
 unifdef-y += gadgetfs.h
 unifdef-y += midi.h
+unifdef-y += g_printer.h
 
diff --git a/include/linux/usb/g_printer.h b/include/linux/usb/g_printer.h
new file mode 100644
index 00000000000..0c5ea1e3eb9
--- /dev/null
+++ b/include/linux/usb/g_printer.h
@@ -0,0 +1,31 @@
+/*
+ * g_printer.h -- Header file for USB Printer gadget driver
+ *
+ * Copyright (C) 2007 Craig W. Nadler
+ *
+ * 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+
+#define PRINTER_NOT_ERROR       0x08
+#define PRINTER_SELECTED        0x10
+#define PRINTER_PAPER_EMPTY     0x20
+
+/* The 'g' code is also used by gadgetfs ioctl requests.
+ * Don't add any colliding codes to either driver, and keep
+ * them in unique ranges (size 0x20 for now).
+ */
+#define GADGET_GET_PRINTER_STATUS       _IOR('g', 0x21, unsigned char)
+#define GADGET_SET_PRINTER_STATUS       _IOWR('g', 0x22, unsigned char)
diff --git a/include/linux/usb/gadgetfs.h b/include/linux/usb/gadgetfs.h
index e8654c33872..981e9ceb8fe 100644
--- a/include/linux/usb/gadgetfs.h
+++ b/include/linux/usb/gadgetfs.h
@@ -59,6 +59,11 @@ struct usb_gadgetfs_event {
 };
 
 
+/* The 'g' code is also used by printer gadget ioctl requests.
+ * Don't add any colliding codes to either driver, and keep
+ * them in unique ranges (size 0x20 for now).
+ */
+
 /* endpoint ioctls */
 
 /* IN transfers may be reported to the gadget driver as complete