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authorCraig W. Nadler <craig@nadler.us>2007-11-11 15:00:15 -0800
committerGreg Kroah-Hartman <gregkh@suse.de>2008-02-01 14:34:49 -0800
commit25a010c8c1a5f0cc2e2794adf969e2df2ad1f0b6 (patch)
tree1d2e477e44a2a8122696711bfd2b9aad35a265bf
parent676d3aa16f66d94bf5654781b77d1e070c8b0514 (diff)
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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>
-rw-r--r--Documentation/usb/gadget_printer.txt510
-rw-r--r--drivers/usb/gadget/Kconfig14
-rw-r--r--drivers/usb/gadget/Makefile3
-rw-r--r--drivers/usb/gadget/printer.c1592
-rw-r--r--include/linux/usb/Kbuild1
-rw-r--r--include/linux/usb/g_printer.h31
-rw-r--r--include/linux/usb/gadgetfs.h5
7 files changed, 2156 insertions, 0 deletions
diff --git a/Documentation/usb/gadget_printer.txt b/Documentation/usb/gadget_printer.txt
new file mode 100644
index 000000000000..ad995bf0db41
--- /dev/null
+++ b/Documentation/usb/gadget_printer.txt
@@ -0,0 +1,510 @@
+
+ Linux USB Printer Gadget Driver
+ 06/04/2007
+
+ Copyright (C) 2007 Craig W. Nadler <craig@nadler.us>
+
+
+
+GENERAL
+=======
+
+This driver may be used if you are writing printer firmware using Linux as
+the embedded OS. This driver has nothing to do with using a printer with
+your Linux host system.
+
+You will need a USB device controller and a Linux driver for it that accepts
+a gadget / "device class" driver using the Linux USB Gadget API. After the
+USB device controller driver is loaded then load the printer gadget driver.
+This will present a printer interface to the USB Host that your USB Device
+port is connected to.
+
+This driver is structured for printer firmware that runs in user mode. The
+user mode printer firmware will read and write data from the kernel mode
+printer gadget driver using a device file. The printer returns a printer status
+byte when the USB HOST sends a device request to get the printer status. The
+user space firmware can read or write this status byte using a device file
+/dev/g_printer . Both blocking and non-blocking read/write calls are supported.
+
+
+
+
+HOWTO USE THIS DRIVER
+=====================
+
+To load the USB device controller driver and the printer gadget driver. The
+following example uses the Netchip 2280 USB device controller driver:
+
+modprobe net2280
+modprobe g_printer
+
+
+The follow command line parameter can be used when loading the printer gadget
+(ex: modprobe g_printer idVendor=0x0525 idProduct=0xa4a8 ):
+
+idVendor - This is the Vendor ID used in the device descriptor. The default is
+ the Netchip vendor id 0x0525. YOU MUST CHANGE TO YOUR OWN VENDOR ID
+ BEFORE RELEASING A PRODUCT. If you plan to release a product and don't
+ already have a Vendor ID please see www.usb.org for details on how to
+ get one.
+
+idProduct - This is the Product ID used in the device descriptor. The default
+ is 0xa4a8, you should change this to an ID that's not used by any of
+ your other USB products if you have any. It would be a good idea to
+ start numbering your products starting with say 0x0001.
+
+bcdDevice - This is the version number of your product. It would be a good idea
+ to put your firmware version here.
+
+iManufacturer - A string containing the name of the Vendor.
+
+iProduct - A string containing the Product Name.
+
+iSerialNum - A string containing the Serial Number. This should be changed for
+ each unit of your product.
+
+iPNPstring - The PNP ID string used for this printer. You will want to set
+ either on the command line or hard code the PNP ID string used for
+ your printer product.
+
+qlen - The number of 8k buffers to use per endpoint. The default is 10, you
+ should tune this for your product. You may also want to tune the
+ size of each buffer for your product.
+
+
+
+
+USING THE EXAMPLE CODE
+======================
+
+This example code talks to stdout, instead of a print engine.
+
+To compile the test code below:
+
+1) save it to a file called prn_example.c
+2) compile the code with the follow command:
+ gcc prn_example.c -o prn_example
+
+
+
+To read printer data from the host to stdout:
+
+ # prn_example -read_data
+
+
+To write printer data from a file (data_file) to the host:
+
+ # cat data_file | prn_example -write_data
+
+
+To get the current printer status for the gadget driver:
+
+ # prn_example -get_status
+
+ Printer status is:
+ Printer is NOT Selected
+ Paper is Out
+ Printer OK
+
+
+To set printer to Selected/On-line:
+
+ # prn_example -selected
+
+
+To set printer to Not Selected/Off-line:
+
+ # prn_example -not_selected
+
+
+To set paper status to paper out:
+
+ # prn_example -paper_out
+
+
+To set paper status to paper loaded:
+
+ # prn_example -paper_loaded
+
+
+To set error status to printer OK:
+
+ # prn_example -no_error
+
+
+To set error status to ERROR:
+
+ # prn_example -error
+
+
+
+
+EXAMPLE CODE
+============
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <linux/poll.h>
+#include <sys/ioctl.h>
+#include <linux/usb/g_printer.h>
+
+#define PRINTER_FILE "/dev/g_printer"
+#define BUF_SIZE 512
+
+
+/*
+ * 'usage()' - Show program usage.
+ */
+
+static void
+usage(const char *option) /* I - Option string or NULL */
+{
+ if (option) {
+ fprintf(stderr,"prn_example: Unknown option \"%s\"!\n",
+ option);
+ }
+
+ fputs("\n", stderr);
+ fputs("Usage: prn_example -[options]\n", stderr);
+ fputs("Options:\n", stderr);
+ fputs("\n", stderr);
+ fputs("-get_status Get the current printer status.\n", stderr);
+ fputs("-selected Set the selected status to selected.\n", stderr);
+ fputs("-not_selected Set the selected status to NOT selected.\n",
+ stderr);
+ fputs("-error Set the error status to error.\n", stderr);
+ fputs("-no_error Set the error status to NO error.\n", stderr);
+ fputs("-paper_out Set the paper status to paper out.\n", stderr);
+ fputs("-paper_loaded Set the paper status to paper loaded.\n",
+ stderr);
+ fputs("-read_data Read printer data from driver.\n", stderr);
+ fputs("-write_data Write printer sata to driver.\n", stderr);
+ fputs("-NB_read_data (Non-Blocking) Read printer data from driver.\n",
+ stderr);
+ fputs("\n\n", stderr);
+
+ exit(1);
+}
+
+
+static int
+read_printer_data()
+{
+ struct pollfd fd[1];
+
+ /* Open device file for printer gadget. */
+ fd[0].fd = open(PRINTER_FILE, O_RDWR);
+ if (fd[0].fd < 0) {
+ printf("Error %d opening %s\n", fd[0].fd, PRINTER_FILE);
+ close(fd[0].fd);
+ return(-1);
+ }
+
+ fd[0].events = POLLIN | POLLRDNORM;
+
+ while (1) {
+ static char buf[BUF_SIZE];
+ int bytes_read;
+ int retval;
+
+ /* Wait for up to 1 second for data. */
+ retval = poll(fd, 1, 1000);
+
+ if (retval && (fd[0].revents & POLLRDNORM)) {
+
+ /* Read data from printer gadget driver. */
+ bytes_read = read(fd[0].fd, buf, BUF_SIZE);
+
+ if (bytes_read < 0) {
+ printf("Error %d reading from %s\n",
+ fd[0].fd, PRINTER_FILE);
+ close(fd[0].fd);
+ return(-1);
+ } else if (bytes_read > 0) {
+ /* Write data to standard OUTPUT (stdout). */
+ fwrite(buf, 1, bytes_read, stdout);
+ fflush(stdout);
+ }
+
+ }
+
+ }
+
+ /* Close the device file. */
+ close(fd[0].fd);
+
+ return 0;
+}
+
+
+static int
+write_printer_data()
+{
+ struct pollfd fd[1];
+
+ /* Open device file for printer gadget. */
+ fd[0].fd = open (PRINTER_FILE, O_RDWR);
+ if (fd[0].fd < 0) {
+ printf("Error %d opening %s\n", fd[0].fd, PRINTER_FILE);
+ close(fd[0].fd);
+ return(-1);
+ }
+
+ fd[0].events = POLLOUT | POLLWRNORM;
+
+ while (1) {
+ int retval;
+ static char buf[BUF_SIZE];
+ /* Read data from standard INPUT (stdin). */
+ int bytes_read = fread(buf, 1, BUF_SIZE, stdin);
+
+ if (!bytes_read) {
+ break;
+ }
+
+ while (bytes_read) {
+
+ /* Wait for up to 1 second to sent data. */
+ retval = poll(fd, 1, 1000);
+
+ /* Write data to printer gadget driver. */
+ if (retval && (fd[0].revents & POLLWRNORM)) {
+ retval = write(fd[0].fd, buf, bytes_read);
+ if (retval < 0) {
+ printf("Error %d writing to %s\n",
+ fd[0].fd,
+ PRINTER_FILE);
+ close(fd[0].fd);
+ return(-1);
+ } else {
+ bytes_read -= retval;
+ }
+
+ }
+
+ }
+
+ }
+
+ /* Wait until the data has been sent. */
+ fsync(fd[0].fd);
+
+ /* Close the device file. */
+ close(fd[0].fd);
+
+ return 0;
+}
+
+
+static int
+read_NB_printer_data()
+{
+ int fd;
+ static char buf[BUF_SIZE];
+ int bytes_read;
+
+ /* Open device file for printer gadget. */
+ fd = open(PRINTER_FILE, O_RDWR|O_NONBLOCK);
+ if (fd < 0) {
+ printf("Error %d opening %s\n", fd, PRINTER_FILE);
+ close(fd);
+ return(-1);
+ }
+
+ while (1) {
+ /* Read data from printer gadget driver. */
+ bytes_read = read(fd, buf, BUF_SIZE);
+ if (bytes_read <= 0) {
+ break;
+ }
+
+ /* Write data to standard OUTPUT (stdout). */
+ fwrite(buf, 1, bytes_read, stdout);
+ fflush(stdout);
+ }
+
+ /* Close the device file. */
+ close(fd);
+
+ return 0;
+}
+
+
+static int
+get_printer_status()
+{
+ int retval;
+ int fd;
+
+ /* Open device file for printer gadget. */
+ fd = open(PRINTER_FILE, O_RDWR);
+ if (fd < 0) {
+ printf("Error %d opening %s\n", fd, PRINTER_FILE);
+ close(fd);
+ return(-1);
+ }
+
+ /* Make the IOCTL call. */
+ retval = ioctl(fd, GADGET_GET_PRINTER_STATUS);
+ if (retval < 0) {
+ fprintf(stderr, "ERROR: Failed to set printer status\n");
+ return(-1);
+ }
+
+ /* Close the device file. */
+ close(fd);
+
+ return(retval);
+}
+
+
+static int
+set_printer_status(unsigned char buf, int clear_printer_status_bit)
+{
+ int retval;
+ int fd;
+
+ retval = get_printer_status();
+ if (retval < 0) {
+ fprintf(stderr, "ERROR: Failed to get printer status\n");
+ return(-1);
+ }
+
+ /* Open device file for printer gadget. */
+ fd = open(PRINTER_FILE, O_RDWR);
+
+ if (fd < 0) {
+ printf("Error %d opening %s\n", fd, PRINTER_FILE);
+ close(fd);
+ return(-1);
+ }
+
+ if (clear_printer_status_bit) {
+ retval &= ~buf;
+ } else {
+ retval |= buf;
+ }
+
+ /* Make the IOCTL call. */
+ if (ioctl(fd, GADGET_SET_PRINTER_STATUS, (unsigned char)retval)) {
+ fprintf(stderr, "ERROR: Failed to set printer status\n");
+ return(-1);
+ }
+
+ /* Close the device file. */
+ close(fd);
+
+ return 0;
+}
+
+
+static int
+display_printer_status()
+{
+ char printer_status;
+
+ printer_status = get_printer_status();
+ if (printer_status < 0) {
+ fprintf(stderr, "ERROR: Failed to get printer status\n");
+ return(-1);
+ }
+
+ printf("Printer status is:\n");
+ if (printer_status & PRINTER_SELECTED) {
+ printf(" Printer is Selected\n");
+ } else {
+ printf(" Printer is NOT Selected\n");
+ }
+ if (printer_status & PRINTER_PAPER_EMPTY) {
+ printf(" Paper is Out\n");
+ } else {
+ printf(" Paper is Loaded\n");
+ }
+ if (printer_status & PRINTER_NOT_ERROR) {
+ printf(" Printer OK\n");
+ } else {
+ printf(" Printer ERROR\n");
+ }
+
+ return(0);
+}
+
+
+int
+main(int argc, char *argv[])
+{
+ int i; /* Looping var */
+ int retval = 0;
+
+ /* No Args */
+ if (argc == 1) {
+ usage(0);
+ exit(0);
+ }
+
+ for (i = 1; i < argc && !retval; i ++) {
+
+ if (argv[i][0] != '-') {
+ continue;
+ }
+
+ if (!strcmp(argv[i], "-get_status")) {
+ if (display_printer_status()) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-paper_loaded")) {
+ if (set_printer_status(PRINTER_PAPER_EMPTY, 1)) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-paper_out")) {
+ if (set_printer_status(PRINTER_PAPER_EMPTY, 0)) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-selected")) {
+ if (set_printer_status(PRINTER_SELECTED, 0)) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-not_selected")) {
+ if (set_printer_status(PRINTER_SELECTED, 1)) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-error")) {
+ if (set_printer_status(PRINTER_NOT_ERROR, 1)) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-no_error")) {
+ if (set_printer_status(PRINTER_NOT_ERROR, 0)) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-read_data")) {
+ if (read_printer_data()) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-write_data")) {
+ if (write_printer_data()) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-NB_read_data")) {
+ if (read_NB_printer_data()) {
+ retval = 1;
+ }
+
+ } else {
+ usage(argv[i]);
+ retval = 1;
+ }
+ }
+
+ exit(retval);
+}
diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
index e706882a8e6f..8a88f24270be 100644
--- a/drivers/usb/gadget/Kconfig
+++ b/drivers/usb/gadget/Kconfig
@@ -548,6 +548,20 @@ config USB_MIDI_GADGET
Say "y" to link the driver statically, or "m" to build a
dynamically linked module called "g_midi".
+config USB_G_PRINTER
+ tristate "Printer Gadget"
+ help
+ 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.
+
+ Say "y" to link the driver statically, or "m" to build a
+ dynamically linked module called "g_printer".
+
+ For more information, see Documentation/usb/gadget_printer.txt
+ which includes sample code for accessing the device file.
# put drivers that need isochronous transfer support (for audio
# or video class gadget drivers), or specific hardware, here.
diff --git a/drivers/usb/gadget/Makefile b/drivers/usb/gadget/Makefile
index 904e57bf6112..c3aab80b6c76 100644
--- a/drivers/usb/gadget/Makefile
+++ b/drivers/usb/gadget/Makefile
@@ -28,6 +28,8 @@ g_midi-objs := gmidi.o usbstring.o config.o epautoconf.o
gadgetfs-objs := inode.o
g_file_storage-objs := file_storage.o usbstring.o config.o \
epautoconf.o
+g_printer-objs := printer.o usbstring.o config.o \
+ epautoconf.o
ifeq ($(CONFIG_USB_ETH_RNDIS),y)
g_ether-objs += rndis.o
@@ -38,5 +40,6 @@ obj-$(CONFIG_USB_ETH) += g_ether.o
obj-$(CONFIG_USB_GADGETFS) += gadgetfs.o
obj-$(CONFIG_USB_FILE_STORAGE) += g_file_storage.o
obj-$(CONFIG_USB_G_SERIAL) += g_serial.o
+obj-$(CONFIG_USB_G_PRINTER) += g_printer.o
obj-$(CONFIG_USB_MIDI_GADGET) += g_midi.o
diff --git a/drivers/usb/gadget/printer.c b/drivers/usb/gadget/printer.c
new file mode 100644
index 000000000000..9fdabc8fcac4
--- /dev/null
+++ b/drivers/usb/gadget/printer.c
@@ -0,0 +1,1592 @@
+/*
+ * printer.c -- Printer gadget driver
+ *
+ * Copyright (C) 2003-2005 David Brownell
+ * Copyright (C) 2006 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
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/ioport.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/smp_lock.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/timer.h>
+#include <linux/list.h>
+#include <linux/interrupt.h>
+#include <linux/utsname.h>
+#include <linux/device.h>
+#include <linux/moduleparam.h>
+#include <linux/fs.h>
+#include <linux/poll.h>
+#include <linux/types.h>
+#include <linux/ctype.h>
+#include <linux/cdev.h>
+
+#include <asm/byteorder.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <asm/system.h>
+#include <linux/uaccess.h>
+#include <asm/unaligned.h>
+
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+#include <linux/usb/g_printer.h>
+
+#include "gadget_chips.h"
+
+#define DRIVER_DESC "Printer Gadget"
+#define DRIVER_VERSION "2007 OCT 06"
+
+static const char shortname [] = "printer";
+static const char driver_desc [] = DRIVER_DESC;
+
+static dev_t g_printer_devno;
+
+static struct class *usb_gadget_class;
+
+/*-------------------------------------------------------------------------*/
+
+struct printer_dev {
+ spinlock_t lock; /* lock this structure */
+ /* lock buffer lists during read/write calls */
+ spinlock_t lock_printer_io;
+ struct usb_gadget *gadget;
+ struct usb_request *req; /* for control responses */
+ u8 config;
+ s8 interface;
+ struct usb_ep *in_ep, *out_ep;
+ const struct usb_endpoint_descriptor
+ *in, *out;
+ struct list_head rx_reqs; /* List of free RX structs */
+ struct list_head rx_reqs_active; /* List of Active RX xfers */
+ struct list_head rx_buffers; /* List of completed xfers */
+ /* wait until there is data to be read. */
+ wait_queue_head_t rx_wait;
+ struct list_head tx_reqs; /* List of free TX structs */
+ struct list_head tx_reqs_active; /* List of Active TX xfers */
+ /* Wait until there are write buffers available to use. */
+ wait_queue_head_t tx_wait;
+ /* Wait until all write buffers have been sent. */
+ wait_queue_head_t tx_flush_wait;
+ struct usb_request *current_rx_req;
+ size_t current_rx_bytes;
+ u8 *current_rx_buf;
+ u8 printer_status;
+ u8 reset_printer;
+ struct class_device *printer_class_dev;
+ struct cdev printer_cdev;
+ struct device *pdev;
+ u8 printer_cdev_open;
+ wait_queue_head_t wait;
+};
+
+static struct printer_dev usb_printer_gadget;
+
+/*-------------------------------------------------------------------------*/
+
+/* DO NOT REUSE THESE IDs with a protocol-incompatible driver!! Ever!!
+ * Instead: allocate your own, using normal USB-IF procedures.
+ */
+
+/* Thanks to NetChip Technologies for donating this product ID.
+ */
+#define PRINTER_VENDOR_NUM 0x0525 /* NetChip */
+#define PRINTER_PRODUCT_NUM 0xa4a8 /* Linux-USB Printer Gadget */
+
+/* Some systems will want different product identifers published in the
+ * device descriptor, either numbers or strings or both. These string
+ * parameters are in UTF-8 (superset of ASCII's 7 bit characters).
+ */
+
+static ushort __initdata idVendor;
+module_param(idVendor, ushort, S_IRUGO);
+MODULE_PARM_DESC(idVendor, "USB Vendor ID");
+
+static ushort __initdata idProduct;
+module_param(idProduct, ushort, S_IRUGO);
+MODULE_PARM_DESC(idProduct, "USB Product ID");
+
+static ushort __initdata bcdDevice;
+module_param(bcdDevice, ushort, S_IRUGO);
+MODULE_PARM_DESC(bcdDevice, "USB Device version (BCD)");
+
+static char *__initdata iManufacturer;
+module_param(iManufacturer, charp, S_IRUGO);
+MODULE_PARM_DESC(iManufacturer, "USB Manufacturer string");
+
+static char *__initdata iProduct;
+module_param(iProduct, charp, S_IRUGO);
+MODULE_PARM_DESC(iProduct, "USB Product string");
+
+static char *__initdata iSerialNum;
+module_param(iSerialNum, charp, S_IRUGO);
+MODULE_PARM_DESC(iSerialNum, "1");
+
+static char *__initdata iPNPstring;
+module_param(iPNPstring, charp, S_IRUGO);
+MODULE_PARM_DESC(iPNPstring, "MFG:linux;MDL:g_printer;CLS:PRINTER;SN:1;");
+
+/* Number of requests to allocate per endpoint, not used for ep0. */
+static unsigned qlen = 10;
+module_param(qlen, uint, S_IRUGO|S_IWUSR);
+
+#define QLEN qlen
+
+#ifdef CONFIG_USB_GADGET_DUALSPEED
+#define DEVSPEED USB_SPEED_HIGH
+#else /* full speed (low speed doesn't do bulk) */
+#define DEVSPEED USB_SPEED_FULL
+#endif
+
+/*-------------------------------------------------------------------------*/
+
+#define xprintk(d, level, fmt, args...) \
+ printk(level "%s: " fmt, DRIVER_DESC, ## args)
+
+#ifdef DEBUG
+#define DBG(dev, fmt, args...) \
+ xprintk(dev, KERN_DEBUG, fmt, ## args)
+#else
+#define DBG(dev, fmt, args...) \
+ do { } while (0)
+#endif /* DEBUG */
+
+#ifdef VERBOSE
+#define VDBG(dev, fmt, args...) \
+ xprintk(dev, KERN_DEBUG, fmt, ## args)
+#else
+#define VDBG(dev, fmt, args...) \
+ do { } while (0)
+#endif /* VERBOSE */
+
+#define ERROR(dev, fmt, args...) \
+ xprintk(dev, KERN_ERR, fmt, ## args)
+#define WARN(dev, fmt, args...) \
+ xprintk(dev, KERN_WARNING, fmt, ## args)
+#define INFO(dev, fmt, args...) \
+ xprintk(dev, KERN_INFO, fmt, ## args)
+
+/*-------------------------------------------------------------------------*/
+
+/* USB DRIVER HOOKUP (to the hardware driver, below us), mostly
+ * ep0 implementation: descriptors, config management, setup().
+ * also optional class-specific notification interrupt transfer.
+ */
+
+/*
+ * DESCRIPTORS ... most are static, but strings and (full) configuration
+ * descriptors are built on demand.
+ */
+
+#define STRING_MANUFACTURER 1
+#define STRING_PRODUCT 2
+#define STRING_SERIALNUM 3
+
+/* holds our biggest descriptor */
+#define USB_DESC_BUFSIZE 256
+#define USB_BUFSIZE 8192
+
+/* This device advertises one configuration. */
+#define DEV_CONFIG_VALUE 1
+#define PRINTER_INTERFACE 0
+
+static struct usb_device_descriptor device_desc = {
+ .bLength = sizeof device_desc,
+ .bDescriptorType = USB_DT_DEVICE,
+ .bcdUSB = __constant_cpu_to_le16(0x0200),
+ .bDeviceClass = USB_CLASS_PER_INTERFACE,
+ .bDeviceSubClass = 0,
+ .bDeviceProtocol = 0,
+ .idVendor = __constant_cpu_to_le16(PRINTER_VENDOR_NUM),
+ .idProduct = __constant_cpu_to_le16(PRINTER_PRODUCT_NUM),
+ .iManufacturer = STRING_MANUFACTURER,
+ .iProduct = STRING_PRODUCT,
+ .iSerialNumber = STRING_SERIALNUM,
+ .bNumConfigurations = 1
+};
+
+static struct usb_otg_descriptor otg_desc = {
+ .bLength = sizeof otg_desc,
+ .bDescriptorType = USB_DT_OTG,
+ .bmAttributes = USB_OTG_SRP
+};
+
+static struct usb_config_descriptor config_desc = {
+ .bLength = sizeof config_desc,
+ .bDescriptorType = USB_DT_CONFIG,
+
+ /* compute wTotalLength on the fly */
+ .bNumInterfaces = 1,
+ .bConfigurationValue = DEV_CONFIG_VALUE,
+ .iConfiguration = 0,
+ .bmAttributes = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
+ .bMaxPower = 1 /* Self-Powered */
+};
+
+static struct usb_interface_descriptor intf_desc = {
+ .bLength = sizeof intf_desc,
+ .bDescriptorType = USB_DT_INTERFACE,
+ .bInterfaceNumber = PRINTER_INTERFACE,
+ .bNumEndpoints = 2,
+ .bInterfaceClass = USB_CLASS_PRINTER,
+ .bInterfaceSubClass = 1, /* Printer Sub-Class */
+ .bInterfaceProtocol = 2, /* Bi-Directional */
+ .iInterface = 0
+};
+
+static struct usb_endpoint_descriptor fs_ep_in_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK
+};
+
+static struct usb_endpoint_descriptor fs_ep_out_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_OUT,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK
+};
+
+static const struct usb_descriptor_header *fs_printer_function [11] = {
+ (struct usb_descriptor_header *) &otg_desc,
+ (struct usb_descriptor_header *) &intf_desc,
+ (struct usb_descriptor_header *) &fs_ep_in_desc,
+ (struct usb_descriptor_header *) &fs_ep_out_desc,
+ NULL
+};
+
+#ifdef CONFIG_USB_GADGET_DUALSPEED
+
+/*
+ * usb 2.0 devices need to expose both high speed and full speed
+ * descriptors, unless they only run at full speed.
+ */
+
+static struct usb_endpoint_descriptor hs_ep_in_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+ .wMaxPacketSize = __constant_cpu_to_le16(512)
+};
+
+static struct usb_endpoint_descriptor hs_ep_out_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+ .wMaxPacketSize = __constant_cpu_to_le16(512)
+};
+
+static struct usb_qualifier_descriptor dev_qualifier = {
+ .bLength = sizeof dev_qualifier,
+ .bDescriptorType = USB_DT_DEVICE_QUALIFIER,
+ .bcdUSB = __constant_cpu_to_le16(0x0200),
+ .bDeviceClass = USB_CLASS_PRINTER,
+ .bNumConfigurations = 1
+};
+
+static const struct usb_descriptor_header *hs_printer_function [11] = {
+ (struct usb_descriptor_header *) &otg_desc,
+ (struct usb_descriptor_header *) &intf_desc,
+ (struct usb_descriptor_header *) &hs_ep_in_desc,
+ (struct usb_descriptor_header *) &hs_ep_out_desc,
+ NULL
+};
+
+/* maxpacket and other transfer characteristics vary by speed. */
+#define ep_desc(g, hs, fs) (((g)->speed == USB_SPEED_HIGH)?(hs):(fs))
+
+#else
+
+/* if there's no high speed support, maxpacket doesn't change. */
+#define ep_desc(g, hs, fs) (((void)(g)), (fs))
+
+#endif /* !CONFIG_USB_GADGET_DUALSPEED */
+
+/*-------------------------------------------------------------------------*/
+
+/* descriptors that are built on-demand */
+
+static char manufacturer [50];
+static char product_desc [40] = DRIVER_DESC;
+static char serial_num [40] = "1";
+static char pnp_string [1024] =
+ "XXMFG:linux;MDL:g_printer;CLS:PRINTER;SN:1;";
+
+/* static strings, in UTF-8 */
+static struct usb_string strings [] = {
+ { STRING_MANUFACTURER, manufacturer, },
+ { STRING_PRODUCT, product_desc, },
+ { STRING_SERIALNUM, serial_num, },
+ { } /* end of list */
+};
+
+static struct usb_gadget_strings stringtab = {
+ .language = 0x0409, /* en-us */
+ .strings = strings,
+};
+
+/*-------------------------------------------------------------------------*/
+
+static struct usb_request *
+printer_req_alloc(struct usb_ep *ep, unsigned len, gfp_t gfp_flags)
+{
+ struct usb_request *req;
+
+ req = usb_ep_alloc_request(ep, gfp_flags);
+
+ if (req != NULL) {
+ req->length = len;
+ req->buf = kmalloc(len, gfp_flags);
+ if (req->buf == NULL) {
+ usb_ep_free_request(ep, req);
+ return NULL;
+ }
+ }
+
+ return req;
+}
+
+static void
+printer_req_free(struct usb_ep *ep, struct usb_request *req)
+{
+ if (ep != NULL && req != NULL) {
+ kfree(req->buf);
+ usb_ep_free_request(ep, req);
+ }
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void rx_complete(struct usb_ep *ep, struct usb_request *req)
+{
+ struct printer_dev *dev = ep->driver_data;
+ int status = req->status;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dev->lock, flags);
+
+ list_del_init(&req->list); /* Remode from Active List */
+
+ switch (status) {
+
+ /* normal completion */
+ case 0:
+ list_add_tail(&req->list, &dev->rx_buffers);
+ wake_up_interruptible(&dev->rx_wait);
+ DBG(dev, "G_Printer : rx length %d\n", req->actual);
+ break;
+
+ /* software-driven interface shutdown */
+ case -ECONNRESET: /* unlink */
+ case -ESHUTDOWN: /* disconnect etc */
+ VDBG(dev, "rx shutdown, code %d\n", status);
+ list_add(&req->list, &dev->rx_reqs);
+ break;
+
+ /* for hardware automagic (such as pxa) */
+ case -ECONNABORTED: /* endpoint reset */
+ DBG(dev, "rx %s reset\n", ep->name);
+ list_add(&req->list, &dev->rx_reqs);
+ break;
+
+ /* data overrun */
+ case -EOVERFLOW:
+ /* FALLTHROUGH */
+
+ default:
+ DBG(dev, "rx status %d\n", status);
+ list_add(&req->list, &dev->rx_reqs);
+ break;
+ }
+ spin_unlock_irqrestore(&dev->lock, flags);
+}
+
+static void tx_complete(struct usb_ep *ep, struct usb_request *req)
+{
+ struct printer_dev *dev = ep->driver_data;
+
+ switch (req->status) {
+ default:
+ VDBG(dev, "tx err %d\n", req->status);
+ /* FALLTHROUGH */
+ case -ECONNRESET: /* unlink */
+ case -ESHUTDOWN: /* disconnect etc */
+ break;
+ case 0:
+ break;
+ }
+
+ spin_lock(&dev->lock);
+ /* Take the request struct off the active list and put it on the
+ * free list.
+ */
+ list_del_init(&req->list);
+ list_add(&req->list, &dev->tx_reqs);
+ wake_up_interruptible(&dev->tx_wait);
+ if (likely(list_empty(&dev->tx_reqs_active)))
+ wake_up_interruptible(&dev->tx_flush_wait);
+
+ spin_unlock(&dev->lock);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int
+printer_open(struct inode *inode, struct file *fd)
+{
+ struct printer_dev *dev;
+ unsigned long flags;
+ int ret = -EBUSY;
+
+ dev = container_of(inode->i_cdev, struct printer_dev, printer_cdev);
+
+ spin_lock_irqsave(&dev->lock, flags);
+
+ if (!dev->printer_cdev_open) {
+ dev->printer_cdev_open = 1;
+ fd->private_data = dev;
+ ret = 0;
+ /* Change the printer status to show that it's on-line. */
+ dev->printer_status |= PRINTER_SELECTED;
+ }
+
+ spin_unlock_irqrestore(&dev->lock, flags);
+
+ DBG(dev, "printer_open returned %x\n", ret);
+
+ return ret;
+}
+
+static int
+printer_close(struct inode *inode, struct file *fd)
+{
+ struct printer_dev *dev = fd->private_data;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dev->lock, flags);
+ dev->printer_cdev_open = 0;
+ fd->private_data = NULL;
+ /* Change printer status to show that the printer is off-line. */
+ dev->printer_status &= ~PRINTER_SELECTED;
+ spin_unlock_irqrestore(&dev->lock, flags);
+
+ DBG(dev, "printer_close\n");
+
+ return 0;
+}
+
+static ssize_t
+printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
+{
+ struct printer_dev *dev = fd->private_data;
+ unsigned long flags;
+ size_t size;
+ size_t bytes_copied;
+ struct usb_request *req;
+ /* This is a pointer to the current USB rx request. */
+ struct usb_request *current_rx_req;
+ /* This is the number of bytes in the current rx buffer. */
+ size_t current_rx_bytes;
+ /* This is a pointer to the current rx buffer. */
+ u8 *current_rx_buf;
+
+ if (len == 0)
+ return -EINVAL;
+
+ DBG(dev, "printer_read trying to read %d bytes\n", (int)len);
+
+ spin_lock(&dev->lock_printer_io);
+ spin_lock_irqsave(&dev->lock, flags);
+
+ /* We will use this flag later to check if a printer reset happened
+ * after we turn interrupts back on.
+ */
+ dev->reset_printer = 0;
+
+ while (likely(!list_empty(&dev->rx_reqs))) {
+ int error;
+
+ req = container_of(dev->rx_reqs.next,
+ struct usb_request, list);
+ list_del_init(&req->list);
+
+ /* The USB Host sends us whatever amount of data it wants to
+ * so we always set the length field to the full USB_BUFSIZE.
+ * If the amount of data is more than the read() caller asked
+ * for it will be stored in the request buffer until it is
+ * asked for by read().
+ */
+ req->length = USB_BUFSIZE;
+ req->complete = rx_complete;
+
+ error = usb_ep_queue(dev->out_ep, req, GFP_ATOMIC);
+ if (error) {
+ DBG(dev, "rx submit --> %d\n", error);
+ list_add(&req->list, &dev->rx_reqs);
+ break;
+ } else {
+ list_add(&req->list, &dev->rx_reqs_active);
+ }
+ }
+
+ bytes_copied = 0;
+ current_rx_req = dev->current_rx_req;
+ current_rx_bytes = dev->current_rx_bytes;
+ current_rx_buf = dev->current_rx_buf;
+ dev->current_rx_req = NULL;
+ dev->current_rx_bytes = 0;
+ dev->current_rx_buf = NULL;
+
+ /* Check if there is any data in the read buffers. Please note that
+ * current_rx_bytes is the number of bytes in the current rx buffer.
+ * If it is zero then check if there are any other rx_buffers that
+ * are on the completed list. We are only out of data if all rx
+ * buffers are empty.
+ */
+ if ((current_rx_bytes == 0) &&
+ (likely(list_empty(&dev->rx_buffers)))) {
+ /* Turn interrupts back on before sleeping. */
+ spin_unlock_irqrestore(&dev->lock, flags);
+
+ /*
+ * If no data is available check if this is a NON-Blocking
+ * call or not.
+ */
+ if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
+ spin_unlock(&dev->lock_printer_io);
+ return -EAGAIN;
+ }
+
+ /* Sleep until data is available */
+ wait_event_interruptible(dev->rx_wait,
+ (likely(!list_empty(&dev->rx_buffers))));
+ spin_lock_irqsave(&dev->lock, flags);
+ }
+
+ /* We have data to return then copy it to the caller's buffer.*/
+ while ((current_rx_bytes || likely(!list_empty(&dev->rx_buffers)))
+ && len) {
+ if (current_rx_bytes == 0) {
+ req = container_of(dev->rx_buffers.next,
+ struct usb_request, list);
+ list_del_init(&req->list);
+
+ if (req->actual && req->buf) {
+ current_rx_req = req;
+ current_rx_bytes = req->actual;
+ current_rx_buf = req->buf;
+ } else {
+ list_add(&req->list, &dev->rx_reqs);
+ continue;
+ }
+ }
+
+ /* Don't leave irqs off while doing memory copies */
+ spin_unlock_irqrestore(&dev->lock, flags);
+
+ if (len > current_rx_bytes)
+ size = current_rx_bytes;
+ else
+ size = len;
+
+ size -= copy_to_user(buf, current_rx_buf, size);
+ bytes_copied += size;
+ len -= size;
+ buf += size;
+
+ spin_lock_irqsave(&dev->lock, flags);
+
+ /* We've disconnected or reset free the req and buffer */
+ if (dev->reset_printer) {
+ printer_req_free(dev->out_ep, current_rx_req);
+ spin_unlock_irqrestore(&dev->lock, flags);
+ spin_unlock(&dev->lock_printer_io);
+ return -EAGAIN;
+ }
+
+ /* If we not returning all the data left in this RX request
+ * buffer then adjust the amount of data left in the buffer.
+ * Othewise if we are done with this RX request buffer then
+ * requeue it to get any incoming data from the USB host.
+ */
+ if (size < current_rx_bytes) {
+ current_rx_bytes -= size;
+ current_rx_buf += size;
+ } else {
+ list_add(&current_rx_req->list, &dev->rx_reqs);
+ current_rx_bytes = 0;
+ current_rx_buf = NULL;
+ current_rx_req = NULL;
+ }
+ }
+
+ dev->current_rx_req = current_rx_req;
+ dev->current_rx_bytes = current_rx_bytes;
+ dev->current_rx_buf = current_rx_buf;
+
+ spin_unlock_irqrestore(&dev->lock, flags);
+ spin_unlock(&dev->lock_printer_io);
+
+ DBG(dev, "printer_read returned %d bytes\n", (int)bytes_copied);
+
+ if (bytes_copied)
+ return bytes_copied;
+ else
+ return -EAGAIN;
+}
+
+static ssize_t
+printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
+{
+ struct printer_dev *dev = fd->private_data;
+ unsigned long flags;
+ size_t size; /* Amount of data in a TX request. */
+ size_t bytes_copied = 0;
+ struct usb_request *req;
+
+ DBG(dev, "printer_write trying to send %d bytes\n", (int)len);
+
+ if (len == 0)
+ return -EINVAL;
+
+ spin_lock(&dev->lock_printer_io);
+ spin_lock_irqsave(&dev->lock, flags);
+
+ /* Check if a printer reset happens while we have interrupts on */
+ dev->reset_printer = 0;
+
+ /* Check if there is any available write buffers */
+ if (likely(list_empty(&dev->tx_reqs))) {
+ /* Turn interrupts back on before sleeping. */
+ spin_unlock_irqrestore(&dev->lock, flags);
+
+ /*
+ * If write buffers are available check if this is
+ * a NON-Blocking call or not.
+ */
+ if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
+ spin_unlock(&dev->lock_printer_io);
+ return -EAGAIN;
+ }
+
+ /* Sleep until a write buffer is available */
+ wait_event_interruptible(dev->tx_wait,
+ (likely(!list_empty(&dev->tx_reqs))));
+ spin_lock_irqsave(&dev->lock, flags);
+ }
+
+ while (likely(!list_empty(&dev->tx_reqs)) && len) {
+
+ if (len > USB_BUFSIZE)
+ size = USB_BUFSIZE;
+ else
+ size = len;
+
+ req = container_of(dev->tx_reqs.next, struct usb_request,
+ list);
+ list_del_init(&req->list);
+
+ req->complete = tx_complete;
+ req->length = size;
+
+ /* Check if we need to send a zero length packet. */
+ if (len > size)
+ /* They will be more TX requests so no yet. */
+ req->zero = 0;
+ else
+ /* If the data amount is not a multple of the
+ * maxpacket size then send a zero length packet.
+ */
+ req->zero = ((len % dev->in_ep->maxpacket) == 0);
+
+ /* Don't leave irqs off while doing memory copies */
+ spin_unlock_irqrestore(&dev->lock, flags);
+
+ if (copy_from_user(req->buf, buf, size)) {
+ list_add(&req->list, &dev->tx_reqs);
+ spin_unlock(&dev->lock_printer_io);
+ return bytes_copied;
+ }
+
+ bytes_copied += size;
+ len -= size;
+ buf += size;
+
+ spin_lock_irqsave(&dev->lock, flags);
+
+ /* We've disconnected or reset so free the req and buffer */
+ if (dev->reset_printer) {
+ printer_req_free(dev->in_ep, req);
+ spin_unlock_irqrestore(&dev->lock, flags);
+ spin_unlock(&dev->lock_printer_io);
+ return -EAGAIN;
+ }
+
+ if (usb_ep_queue(dev->in_ep, req, GFP_ATOMIC)) {
+ list_add(&req->list, &dev->tx_reqs);
+ spin_unlock_irqrestore(&dev->lock, flags);
+ spin_unlock(&dev->lock_printer_io);
+ return -EAGAIN;
+ }
+
+ list_add(&req->list, &dev->tx_reqs_active);
+
+ }
+
+ spin_unlock_irqrestore(&dev->lock, flags);
+ spin_unlock(&dev->lock_printer_io);
+
+ DBG(dev, "printer_write sent %d bytes\n", (int)bytes_copied);
+
+ if (bytes_copied) {
+ return bytes_copied;
+ } else {
+ return -EAGAIN;
+ }
+}
+
+static int
+printer_fsync(struct file *fd, struct dentry *dentry, int datasync)
+{
+ struct printer_dev *dev = fd->private_data;
+ unsigned long flags;
+ int tx_list_empty;
+
+ spin_lock_irqsave(&dev->lock, flags);
+ tx_list_empty = (likely(list_empty(&dev->tx_reqs)));
+ spin_unlock_irqrestore(&dev->lock, flags);
+
+ if (!tx_list_empty) {
+ /* Sleep until all data has been sent */
+ wait_event_interruptible(dev->tx_flush_wait,
+ (likely(list_empty(&dev->tx_reqs_active))));
+ }
+
+ return 0;
+}
+
+static unsigned int
+printer_poll(struct file *fd, poll_table *wait)
+{
+ struct printer_dev *dev = fd->private_data;
+ unsigned long flags;
+ int status = 0;
+
+ poll_wait(fd, &dev->rx_wait, wait);
+ poll_wait(fd, &dev->tx_wait, wait);
+
+ spin_lock_irqsave(&dev->lock, flags);
+ if (likely(!list_empty(&dev->tx_reqs)))
+ status |= POLLOUT | POLLWRNORM;
+
+ if (likely(!list_empty(&dev->rx_buffers)))
+ status |= POLLIN | POLLRDNORM;
+
+ spin_unlock_irqrestore(&dev->lock, flags);
+
+ return status;
+}
+
+static int
+printer_ioctl(struct inode *inode, struct file *fd, unsigned int code,
+ unsigned long arg)
+{
+ struct printer_dev *dev = fd->private_data;
+ unsigned long flags;
+ int status = 0;
+
+ DBG(dev, "printer_ioctl: cmd=0x%4.4x, arg=%lu\n", code, arg);
+
+ /* handle ioctls */
+
+ spin_lock_irqsave(&dev->lock, flags);
+
+ switch (code) {
+ case GADGET_GET_PRINTER_STATUS:
+ status = (int)dev->printer_status;
+ break;
+ case GADGET_SET_PRINTER_STATUS:
+ dev->printer_status = (u8)arg;
+ break;
+ default:
+ /* could not handle ioctl */
+ DBG(dev, "printer_ioctl: ERROR cmd=0x%4.4xis not supported\n",
+ code);
+ status = -ENOTTY;
+ }
+
+ spin_unlock_irqrestore(&dev->lock, flags);
+
+ return status;
+}
+
+/* used after endpoint configuration */
+static struct file_operations printer_io_operations = {
+ .owner = THIS_MODULE,
+ .open = printer_open,
+ .read = printer_read,
+ .write = printer_write,
+ .fsync = printer_fsync,
+ .poll = printer_poll,
+ .ioctl = printer_ioctl,
+ .release = printer_close
+};
+
+/*-------------------------------------------------------------------------*/
+
+static int
+set_printer_interface(struct printer_dev *dev)
+{
+ int result = 0;
+
+ dev->in = ep_desc(dev->gadget, &hs_ep_in_desc, &fs_ep_in_desc);
+ dev->in_ep->driver_data = dev;
+
+ dev->out = ep_desc(dev->gadget, &hs_ep_out_desc, &fs_ep_out_desc);
+ dev->out_ep->driver_data = dev;
+
+ result = usb_ep_enable(dev->in_ep, dev->in);
+ if (result != 0) {
+ DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
+ goto done;
+ }
+
+ result = usb_ep_enable(dev->out_ep, dev->out);
+ if (result != 0) {
+ DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
+ goto done;
+ }
+
+done:
+ /* on error, disable any endpoints */
+ if (result != 0) {
+ (void) usb_ep_disable(dev->in_ep);
+ (void) usb_ep_disable(dev->out_ep);
+ dev->in = NULL;
+ dev->out = NULL;
+ }
+
+ /* caller is responsible for cleanup on error */
+ return result;
+}
+
+static void printer_reset_interface(struct printer_dev *dev)
+{
+ if (dev->interface < 0)
+ return;
+
+ DBG(dev, "%s\n", __FUNCTION__);
+
+ if (dev->in)
+ usb_ep_disable(dev->in_ep);
+
+ if (dev->out)
+ usb_ep_disable(dev->out_ep);
+
+ dev->interface = -1;
+}
+
+/* change our operational config. must agree with the code
+ * that returns config descriptors, and altsetting code.
+ */
+static int
+printer_set_config(struct printer_dev *dev, unsigned number)
+{
+ int result = 0;
+ struct usb_gadget *gadget = dev->gadget;
+
+ if (gadget_is_sa1100(gadget) && dev->config) {
+ /* tx fifo is full, but we can't clear it...*/
+ INFO(dev, "can't change configurations\n");
+ return -ESPIPE;
+ }
+
+ switch (number) {
+ case DEV_CONFIG_VALUE:
+ result = 0;
+ break;
+ default:
+ result = -EINVAL;
+ /* FALL THROUGH */
+ case 0:
+ break;
+ }
+
+ if (result) {
+ usb_gadget_vbus_draw(dev->gadget,
+ dev->gadget->is_otg ? 8 : 100);
+ } else {
+ char *speed;
+ unsigned power;
+
+ power = 2 * config_desc.bMaxPower;
+ usb_gadget_vbus_draw(dev->gadget, power);
+
+ switch (gadget->speed) {
+ case USB_SPEED_FULL: speed = "full"; break;
+#ifdef CONFIG_USB_GADGET_DUALSPEED
+ case USB_SPEED_HIGH: speed = "high"; break;
+#endif
+ default: speed = "?"; break;
+ }
+
+ dev->config = number;
+ INFO(dev, "%s speed config #%d: %d mA, %s\n",
+ speed, number, power, driver_desc);
+ }
+ return result;
+}
+
+static int
+config_buf(enum usb_device_speed speed, u8 *buf, u8 type, unsigned index,
+ int is_otg)
+{
+ int len;
+ const struct usb_descriptor_header **function;
+#ifdef CONFIG_USB_GADGET_DUALSPEED
+ int hs = (speed == USB_SPEED_HIGH);
+
+ if (type == USB_DT_OTHER_SPEED_CONFIG)
+ hs = !hs;
+
+ if (hs) {
+ function = hs_printer_function;
+ } else {
+ function = fs_printer_function;
+ }
+#else
+ function = fs_printer_function;
+#endif
+
+ if (index >= device_desc.bNumConfigurations)
+ return -EINVAL;
+
+ /* for now, don't advertise srp-only devices */
+ if (!is_otg)
+ function++;
+
+ len = usb_gadget_config_buf(&config_desc, buf, USB_DESC_BUFSIZE,
+ function);
+ if (len < 0)
+ return len;
+ ((struct usb_config_descriptor *) buf)->bDescriptorType = type;
+ return len;
+}
+
+/* Change our operational Interface. */
+static int
+set_interface(struct printer_dev *dev, unsigned number)
+{
+ int result = 0;
+
+ if (gadget_is_sa1100(dev->gadget) && dev->interface < 0) {
+ /* tx fifo is full, but we can't clear it...*/
+ INFO(dev, "can't change interfaces\n");
+ return -ESPIPE;
+ }
+
+ /* Free the current interface */
+ switch (dev->interface) {
+ case PRINTER_INTERFACE:
+ printer_reset_interface(dev);
+ break;
+ }
+
+ switch (number) {
+ case PRINTER_INTERFACE:
+ result = set_printer_interface(dev);
+ if (result) {
+ printer_reset_interface(dev);
+ } else {
+ dev->interface = PRINTER_INTERFACE;
+ }
+ break;
+ default:
+ result = -EINVAL;
+ /* FALL THROUGH */
+ }
+
+ if (!result)
+ INFO(dev, "Using interface %x\n", number);
+
+ return result;
+}
+
+static void printer_setup_complete(struct usb_ep *ep, struct usb_request *req)
+{
+ if (req->status || req->actual != req->length)
+ DBG((struct printer_dev *) ep->driver_data,
+ "setup complete --> %d, %d/%d\n",
+ req->status, req->actual, req->length);
+}
+
+static void printer_soft_reset(struct printer_dev *dev)
+{
+ struct usb_request *req;
+
+ INFO(dev, "Received Printer Reset Request\n");
+
+ if (usb_ep_disable(dev->in_ep))
+ DBG(dev, "Failed to disable USB in_ep\n");
+ if (usb_ep_disable(dev->out_ep))
+ DBG(dev, "Failed to disable USB out_ep\n");
+
+ if (dev->current_rx_req != NULL) {
+ list_add(&dev->current_rx_req->list, &dev->rx_reqs);
+ dev->current_rx_req = NULL;
+ }
+ dev->current_rx_bytes = 0;
+ dev->current_rx_buf = NULL;
+ dev->reset_printer = 1;
+
+ while (likely(!(list_empty(&dev->rx_buffers)))) {
+ req = container_of(dev->rx_buffers.next, struct usb_request,
+ list);
+ list_del_init(&req->list);
+ list_add(&req->list, &dev->rx_reqs);
+ }
+
+ while (likely(!(list_empty(&dev->rx_reqs_active)))) {
+ req = container_of(dev->rx_buffers.next, struct usb_request,
+ list);
+ list_del_init(&req->list);
+ list_add(&req->list, &dev->rx_reqs);
+ }
+
+ while (likely(!(list_empty(&dev->tx_reqs_active)))) {
+ req = container_of(dev->tx_reqs_active.next,
+ struct usb_request, list);
+ list_del_init(&req->list);
+ list_add(&req->list, &dev->tx_reqs);
+ }
+
+ if (usb_ep_enable(dev->in_ep, dev->in))
+ DBG(dev, "Failed to enable USB in_ep\n");
+ if (usb_ep_enable(dev->out_ep, dev->out))
+ DBG(dev, "Failed to enable USB out_ep\n");
+
+ wake_up_interruptible(&dev->tx_wait);
+ wake_up_interruptible(&dev->tx_flush_wait);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * The setup() callback implements all the ep0 functionality that's not
+ * handled lower down.
+ */
+static int
+printer_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
+{
+ struct printer_dev *dev = get_gadget_data(gadget);
+ struct usb_request *req = dev->req;
+ int value = -EOPNOTSUPP;
+ u16 wIndex = le16_to_cpu(ctrl->wIndex);
+ u16 wValue = le16_to_cpu(ctrl->wValue);
+ u16 wLength = le16_to_cpu(ctrl->wLength);
+
+ DBG(dev, "ctrl req%02x.%02x v%04x i%04x l%d\n",
+ ctrl->bRequestType, ctrl->bRequest, wValue, wIndex, wLength);
+
+ req->complete = printer_setup_complete;
+
+ switch (ctrl->bRequestType&USB_TYPE_MASK) {
+
+ case USB_TYPE_STANDARD:
+ switch (ctrl->bRequest) {
+
+ case USB_REQ_GET_DESCRIPTOR:
+ if (ctrl->bRequestType != USB_DIR_IN)
+ break;
+ switch (wValue >> 8) {
+
+ case USB_DT_DEVICE:
+ value = min(wLength, (u16) sizeof device_desc);
+ memcpy(req->buf, &device_desc, value);
+ break;
+#ifdef CONFIG_USB_GADGET_DUALSPEED
+ case USB_DT_DEVICE_QUALIFIER:
+ if (!gadget->is_dualspeed)
+ break;
+ value = min(wLength,
+ (u16) sizeof dev_qualifier);
+ memcpy(req->buf, &dev_qualifier, value);
+ break;
+
+ case USB_DT_OTHER_SPEED_CONFIG:
+ if (!gadget->is_dualspeed)
+ break;
+ /* FALLTHROUGH */
+#endif /* CONFIG_USB_GADGET_DUALSPEED */
+ case USB_DT_CONFIG:
+ value = config_buf(gadget->speed, req->buf,
+ wValue >> 8,
+ wValue & 0xff,
+ gadget->is_otg);
+ if (value >= 0)
+ value = min(wLength, (u16) value);
+ break;
+
+ case USB_DT_STRING:
+ value = usb_gadget_get_string(&stringtab,
+ wValue & 0xff, req->buf);
+ if (value >= 0)
+ value = min(wLength, (u16) value);
+ break;
+ }
+ break;
+
+ case USB_REQ_SET_CONFIGURATION:
+ if (ctrl->bRequestType != 0)
+ break;
+ if (gadget->a_hnp_support)
+ DBG(dev, "HNP available\n");
+ else if (gadget->a_alt_hnp_support)
+ DBG(dev, "HNP needs a different root port\n");
+ value = printer_set_config(dev, wValue);
+ break;
+ case USB_REQ_GET_CONFIGURATION:
+ if (ctrl->bRequestType != USB_DIR_IN)
+ break;
+ *(u8 *)req->buf = dev->config;
+ value = min(wLength, (u16) 1);
+ break;
+
+ case USB_REQ_SET_INTERFACE:
+ if (ctrl->bRequestType != USB_RECIP_INTERFACE ||
+ !dev->config)
+ break;
+
+ value = set_interface(dev, PRINTER_INTERFACE);
+ break;
+ case USB_REQ_GET_INTERFACE:
+ if (ctrl->bRequestType !=
+ (USB_DIR_IN|USB_RECIP_INTERFACE)
+ || !dev->config)
+ break;
+
+ *(u8 *)req->buf = dev->interface;
+ value = min(wLength, (u16) 1);
+ break;
+
+ default:
+ goto unknown;
+ }
+ break;
+
+ case USB_TYPE_CLASS:
+ switch (ctrl->bRequest) {
+ case 0: /* Get the IEEE-1284 PNP String */
+ /* Only one printer interface is supported. */
+ if ((wIndex>>8) != PRINTER_INTERFACE)
+ break;
+
+ value = (pnp_string[0]<<8)|pnp_string[1];
+ memcpy(req->buf, pnp_string, value);
+ DBG(dev, "1284 PNP String: %x %s\n", value,
+ &pnp_string[2]);
+ break;
+
+ case 1: /* Get Port Status */
+ /* Only one printer interface is supported. */
+ if (wIndex != PRINTER_INTERFACE)
+ break;
+
+ *(u8 *)req->buf = dev->printer_status;
+ value = min(wLength, (u16) 1);
+ break;
+
+ case 2: /* Soft Reset */
+ /* Only one printer interface is supported. */
+ if (wIndex != PRINTER_INTERFACE)
+ break;
+
+ printer_soft_reset(dev);
+
+ value = 0;
+ break;
+
+ default:
+ goto unknown;
+ }
+ break;
+
+ default:
+unknown:
+ VDBG(dev,
+ "unknown ctrl req%02x.%02x v%04x i%04x l%d\n",
+ ctrl->bRequestType, ctrl->bRequest,
+ wValue, wIndex, wLength);
+ break;
+ }
+
+ /* respond with data transfer before status phase? */
+ if (value >= 0) {
+ req->length = value;
+ req->zero = value < wLength
+ && (value % gadget->ep0->maxpacket) == 0;
+ value = usb_ep_queue(gadget->ep0, req, GFP_ATOMIC);
+ if (value < 0) {
+ DBG(dev, "ep_queue --> %d\n", value);
+ req->status = 0;
+ printer_setup_complete(gadget->ep0, req);
+ }
+ }
+
+ /* host either stalls (value < 0) or reports success */
+ return value;
+}
+
+static void
+printer_disconnect(struct usb_gadget *gadget)
+{
+ struct printer_dev *dev = get_gadget_data(gadget);
+ unsigned long flags;
+
+ DBG(dev, "%s\n", __FUNCTION__);
+
+ spin_lock_irqsave(&dev->lock, flags);
+
+ printer_reset_interface(dev);
+
+ spin_unlock_irqrestore(&dev->lock, flags);
+}
+
+static void
+printer_unbind(struct usb_gadget *gadget)
+{
+ struct printer_dev *dev = get_gadget_data(gadget);
+ struct usb_request *req;
+
+
+ DBG(dev, "%s\n", __FUNCTION__);
+
+ /* Remove sysfs files */
+ device_destroy(usb_gadget_class, g_printer_devno);
+
+ /* Remove Character Device */
+ cdev_del(&dev->printer_cdev);
+
+ /* we must already have been disconnected ... no i/o may be active */
+ WARN_ON(!list_empty(&dev->tx_reqs_active));
+ WARN_ON(!list_empty(&dev->rx_reqs_active));
+
+ /* Free all memory for this driver. */
+ while (!list_empty(&dev->tx_reqs)) {
+ req = container_of(dev->tx_reqs.next, struct usb_request,
+ list);
+ list_del(&req->list);
+ printer_req_free(dev->in_ep, req);
+ }
+
+ if (dev->current_rx_req != NULL);
+ printer_req_free(dev->out_ep, dev->current_rx_req);
+
+ while (!list_empty(&dev->rx_reqs)) {
+ req = container_of(dev->rx_reqs.next,
+ struct usb_request, list);
+ list_del(&req->list);
+ printer_req_free(dev->out_ep, req);
+ }
+
+ while (!list_empty(&dev->rx_buffers)) {
+ req = container_of(dev->rx_buffers.next,
+ struct usb_request, list);
+ list_del(&req->list);
+ printer_req_free(dev->out_ep, req);
+ }
+
+ if (dev->req) {
+ printer_req_free(gadget->ep0, dev->req);
+ dev->req = NULL;
+ }
+
+ set_gadget_data(gadget, NULL);
+}
+
+static int __init
+printer_bind(struct usb_gadget *gadget)
+{
+ struct printer_dev *dev;
+ struct usb_ep *in_ep, *out_ep;
+ int status = -ENOMEM;
+ int gcnum;
+ size_t len;
+ u32 i;
+ struct usb_request *req;
+
+ dev = &usb_printer_gadget;
+
+
+ /* Setup the sysfs files for the printer gadget. */
+ dev->pdev = device_create(usb_gadget_class, NULL, g_printer_devno,
+ "g_printer");
+ if (IS_ERR(dev->pdev)) {
+ ERROR(dev, "Failed to create device: g_printer\n");
+ goto fail;
+ }
+
+ /*
+ * Register a character device as an interface to a user mode
+ * program that handles the printer specific functionality.
+ */
+ cdev_init(&dev->printer_cdev, &printer_io_operations);
+ dev->printer_cdev.owner = THIS_MODULE;
+ status = cdev_add(&dev->printer_cdev, g_printer_devno, 1);
+ if (status) {
+ ERROR(dev, "Failed to open char device\n");
+ goto fail;
+ }
+
+ if (gadget_is_sa1100(gadget)) {
+ /* hardware can't write zero length packets. */
+ ERROR(dev, "SA1100 controller is unsupport by this driver\n");
+ goto fail;
+ }
+
+ gcnum = usb_gadget_controller_number(gadget);
+ if (gcnum >= 0) {
+ device_desc.bcdDevice = cpu_to_le16(0x0200 + gcnum);
+ } else {
+ dev_warn(&gadget->dev, "controller '%s' not recognized\n",
+ gadget->name);
+ /* unrecognized, but safe unless bulk is REALLY quirky */
+ device_desc.bcdDevice =
+ __constant_cpu_to_le16(0xFFFF);
+ }
+ snprintf(manufacturer, sizeof(manufacturer), "%s %s with %s",
+ init_utsname()->sysname, init_utsname()->release,
+ gadget->name);
+
+ device_desc.idVendor =
+ __constant_cpu_to_le16(PRINTER_VENDOR_NUM);
+ device_desc.idProduct =
+ __constant_cpu_to_le16(PRINTER_PRODUCT_NUM);
+
+ /* support optional vendor/distro customization */
+ if (idVendor) {
+ if (!idProduct) {
+ dev_err(&gadget->dev, "idVendor needs idProduct!\n");
+ return -ENODEV;
+ }
+ device_desc.idVendor = cpu_to_le16(idVendor);
+ device_desc.idProduct = cpu_to_le16(idProduct);
+ if (bcdDevice)
+ device_desc.bcdDevice = cpu_to_le16(bcdDevice);
+ }
+
+ if (iManufacturer)
+ strlcpy(manufacturer, iManufacturer, sizeof manufacturer);
+
+ if (iProduct)
+ strlcpy(product_desc, iProduct, sizeof product_desc);
+
+ if (iSerialNum)
+ strlcpy(serial_num, iSerialNum, sizeof serial_num);
+
+ if (iPNPstring)
+ strlcpy(&pnp_string[2], iPNPstring, (sizeof pnp_string)-2);
+
+ len = strlen(pnp_string);
+ pnp_string[0] = (len >> 8) & 0xFF;
+ pnp_string[1] = len & 0xFF;
+
+ /* all we really need is bulk IN/OUT */
+ usb_ep_autoconfig_reset(gadget);
+ in_ep = usb_ep_autoconfig(gadget, &fs_ep_in_desc);
+ if (!in_ep) {
+autoconf_fail:
+ dev_err(&gadget->dev, "can't autoconfigure on %s\n",
+ gadget->name);
+ return -ENODEV;
+ }
+ in_ep->driver_data = in_ep; /* claim */
+
+ out_ep = usb_ep_autoconfig(gadget, &fs_ep_out_desc);
+ if (!out_ep)
+ goto autoconf_fail;
+ out_ep->driver_data = out_ep; /* claim */
+
+#ifdef CONFIG_USB_GADGET_DUALSPEED
+ /* assumes ep0 uses the same value for both speeds ... */
+ dev_qualifier.bMaxPacketSize0 = device_desc.bMaxPacketSize0;
+
+ /* and that all endpoints are dual-speed */
+ hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
+ hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
+#endif /* DUALSPEED */
+
+ device_desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
+ usb_gadget_set_selfpowered(gadget);
+
+ if (gadget->is_otg) {
+ otg_desc.bmAttributes |= USB_OTG_HNP,
+ config_desc.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
+ config_desc.bMaxPower = 4;
+ }
+
+ spin_lock_init(&dev->lock);
+ spin_lock_init(&dev->lock_printer_io);
+ INIT_LIST_HEAD(&dev->tx_reqs);
+ INIT_LIST_HEAD(&dev->tx_reqs_active);
+ INIT_LIST_HEAD(&dev->rx_reqs);
+ INIT_LIST_HEAD(&dev->rx_reqs_active);
+ INIT_LIST_HEAD(&dev->rx_buffers);
+ init_waitqueue_head(&dev->rx_wait);
+ init_waitqueue_head(&dev->tx_wait);
+ init_waitqueue_head(&dev->tx_flush_wait);
+
+ dev->config = 0;
+ dev->interface = -1;
+ dev->printer_cdev_open = 0;
+ dev->printer_status = PRINTER_NOT_ERROR;
+ dev->current_rx_req = NULL;
+ dev->current_rx_bytes = 0;
+ dev->current_rx_buf = NULL;
+
+ dev->in_ep = in_ep;
+ dev->out_ep = out_ep;
+
+ /* preallocate control message data and buffer */
+ dev->req = printer_req_alloc(gadget->ep0, USB_DESC_BUFSIZE,
+ GFP_KERNEL);
+ if (!dev->req) {
+ status = -ENOMEM;
+ goto fail;
+ }
+
+ for (i = 0; i < QLEN; i++) {
+ req = printer_req_alloc(dev->in_ep, USB_BUFSIZE, GFP_KERNEL);
+ if (!req) {
+ while (!list_empty(&dev->tx_reqs)) {
+ req = container_of(dev->tx_reqs.next,
+ struct usb_request, list);
+ list_del(&req->list);
+ printer_req_free(dev->in_ep, req);
+ }
+ return -ENOMEM;
+ }
+ list_add(&req->list, &dev->tx_reqs);
+ }
+
+ for (i = 0; i < QLEN; i++) {
+ req = printer_req_alloc(dev->out_ep, USB_BUFSIZE, GFP_KERNEL);
+ if (!req) {
+ while (!list_empty(&dev->rx_reqs)) {
+ req = container_of(dev->rx_reqs.next,
+ struct usb_request, list);
+ list_del(&req->list);
+ printer_req_free(dev->out_ep, req);
+ }
+ return -ENOMEM;
+ }
+ list_add(&req->list, &dev->rx_reqs);
+ }
+
+ dev->req->complete = printer_setup_complete;
+
+ /* finish hookup to lower layer ... */
+ dev->gadget = gadget;
+ set_gadget_data(gadget, dev);
+ gadget->ep0->driver_data = dev;
+
+ INFO(dev, "%s, version: " DRIVER_VERSION "\n", driver_desc);
+ INFO(dev, "using %s, OUT %s IN %s\n", gadget->name, out_ep->name,
+ in_ep->name);
+
+ return 0;
+
+fail:
+ printer_unbind(gadget);
+ return status;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static struct usb_gadget_driver printer_driver = {
+ .speed = DEVSPEED,
+
+ .function = (char *) driver_desc,
+ .bind = printer_bind,
+ .unbind = printer_unbind,
+
+ .setup = printer_setup,
+ .disconnect = printer_disconnect,
+
+ .driver = {
+ .name = (char *) shortname,
+ .owner = THIS_MODULE,
+ },
+};
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR("Craig Nadler");
+MODULE_LICENSE("GPL");
+
+static int __init
+init(void)
+{
+ int status;
+
+ usb_gadget_class = class_create(THIS_MODULE, "usb_printer_gadget");
+ if (IS_ERR(usb_gadget_class)) {
+ status = PTR_ERR(usb_gadget_class);
+ ERROR(dev, "unable to create usb_gadget class %d\n", status);
+ return status;
+ }
+
+ status = alloc_chrdev_region(&g_printer_devno, 0, 1,
+ "USB printer gadget");
+ if (status) {
+ ERROR(dev, "alloc_chrdev_region %d\n", status);
+ class_destroy(usb_gadget_class);
+ return status;
+ }
+
+ status = usb_gadget_register_driver(&printer_driver);
+ if (status) {
+ class_destroy(usb_gadget_class);
+ unregister_chrdev_region(g_printer_devno, 1);
+ DBG(dev, "usb_gadget_register_driver %x\n", status);
+ }
+
+ return status;
+}
+module_init(init);
+
+static void __exit
+cleanup(void)
+{
+ int status;
+
+ spin_lock(&usb_printer_gadget.lock_printer_io);
+ class_destroy(usb_gadget_class);
+ unregister_chrdev_region(g_printer_devno, 2);
+
+ status = usb_gadget_unregister_driver(&printer_driver);
+ if (status)
+ ERROR(dev, "usb_gadget_unregister_driver %x\n", status);
+
+ spin_unlock(&usb_printer_gadget.lock_printer_io);
+}
+module_exit(cleanup);
diff --git a/include/linux/usb/Kbuild b/include/linux/usb/Kbuild
index 6ce42bf9f743..74a9ce78e7a9 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 000000000000..0c5ea1e3eb98
--- /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 e8654c338729..981e9ceb8fe7 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