drivers/usb/gadget/legacy/printer.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * printer.c -- Printer gadget driver
   4  *
   5  * Copyright (C) 2003-2005 David Brownell
   6  * Copyright (C) 2006 Craig W. Nadler
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/kernel.h>
  11 #include <asm/byteorder.h>
  12
  13 #include <linux/usb/ch9.h>
  14 #include <linux/usb/composite.h>
  15 #include <linux/usb/gadget.h>
  16 #include <linux/usb/g_printer.h>
  17
  18 USB_GADGET_COMPOSITE_OPTIONS();
  19
  20 #define DRIVER_DESC             "Printer Gadget"
  21 #define DRIVER_VERSION          "2015 FEB 17"
  22
  23 static const char shortname [] = "printer";
  24 static const char driver_desc [] = DRIVER_DESC;
  25
  26 #include "u_printer.h"
  27
  28 /*-------------------------------------------------------------------------*/
  29
  30 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
  31  * Instead:  allocate your own, using normal USB-IF procedures.
  32  */
  33
  34 /* Thanks to NetChip Technologies for donating this product ID.
  35  */
  36 #define PRINTER_VENDOR_NUM      0x0525          /* NetChip */
  37 #define PRINTER_PRODUCT_NUM     0xa4a8          /* Linux-USB Printer Gadget */
  38
  39 /* Some systems will want different product identifiers published in the
  40  * device descriptor, either numbers or strings or both.  These string
  41  * parameters are in UTF-8 (superset of ASCII's 7 bit characters).
  42  */
  43
  44 module_param_named(iSerialNum, coverwrite.serial_number, charp, S_IRUGO);
  45 MODULE_PARM_DESC(iSerialNum, "1");
  46
  47 static char *iPNPstring;
  48 module_param(iPNPstring, charp, S_IRUGO);
  49 MODULE_PARM_DESC(iPNPstring, "MFG:linux;MDL:g_printer;CLS:PRINTER;SN:1;");
  50
  51 /* Number of requests to allocate per endpoint, not used for ep0. */
  52 static unsigned qlen = 10;
  53 module_param(qlen, uint, S_IRUGO|S_IWUSR);
  54
  55 #define QLEN    qlen
  56
  57 static struct usb_function_instance *fi_printer;
  58 static struct usb_function *f_printer;
  59
  60 /*-------------------------------------------------------------------------*/
  61
  62 /*
  63  * DESCRIPTORS ... most are static, but strings and (full) configuration
  64  * descriptors are built on demand.
  65  */
  66
  67 static struct usb_device_descriptor device_desc = {
  68         .bLength =              sizeof device_desc,
  69         .bDescriptorType =      USB_DT_DEVICE,
  70         /* .bcdUSB = DYNAMIC */
  71         .bDeviceClass =         USB_CLASS_PER_INTERFACE,
  72         .bDeviceSubClass =      0,
  73         .bDeviceProtocol =      0,
  74         .idVendor =             cpu_to_le16(PRINTER_VENDOR_NUM),
  75         .idProduct =            cpu_to_le16(PRINTER_PRODUCT_NUM),
  76         .bNumConfigurations =   1
  77 };
  78
  79 static const struct usb_descriptor_header *otg_desc[2];
  80
  81 /*-------------------------------------------------------------------------*/
  82
  83 /* descriptors that are built on-demand */
  84
  85 static char                             product_desc [40] = DRIVER_DESC;
  86 static char                             serial_num [40] = "1";
  87 static char                             *pnp_string =
  88         "MFG:linux;MDL:g_printer;CLS:PRINTER;SN:1;";
  89
  90 /* static strings, in UTF-8 */
  91 static struct usb_string                strings [] = {
  92         [USB_GADGET_MANUFACTURER_IDX].s = "",
  93         [USB_GADGET_PRODUCT_IDX].s = product_desc,
  94         [USB_GADGET_SERIAL_IDX].s =     serial_num,
  95         {  }            /* end of list */
  96 };
  97
  98 static struct usb_gadget_strings        stringtab_dev = {
  99         .language       = 0x0409,       /* en-us */
 100         .strings        = strings,
 101 };
 102
 103 static struct usb_gadget_strings *dev_strings[] = {
 104         &stringtab_dev,
 105         NULL,
 106 };
 107
 108 static struct usb_configuration printer_cfg_driver = {
 109         .label                  = "printer",
 110         .bConfigurationValue    = 1,
 111         .bmAttributes           = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
 112 };
 113
 114 static int printer_do_config(struct usb_configuration *c)
 115 {
 116         struct usb_gadget       *gadget = c->cdev->gadget;
 117         int                     status = 0;
 118
 119         usb_ep_autoconfig_reset(gadget);
 120
 121         usb_gadget_set_selfpowered(gadget);
 122
 123         if (gadget_is_otg(gadget)) {
 124                 printer_cfg_driver.descriptors = otg_desc;
 125                 printer_cfg_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 126         }
 127
 128         f_printer = usb_get_function(fi_printer);
 129         if (IS_ERR(f_printer))
 130                 return PTR_ERR(f_printer);
 131
 132         status = usb_add_function(c, f_printer);
 133         if (status < 0)
 134                 usb_put_function(f_printer);
 135
 136         return status;
 137 }
 138
 139 static int printer_bind(struct usb_composite_dev *cdev)
 140 {
 141         struct f_printer_opts *opts;
 142         int ret;
 143
 144         fi_printer = usb_get_function_instance("printer");
 145         if (IS_ERR(fi_printer))
 146                 return PTR_ERR(fi_printer);
 147
 148         opts = container_of(fi_printer, struct f_printer_opts, func_inst);
 149         opts->minor = 0;
 150         opts->q_len = QLEN;
 151         if (iPNPstring) {
 152                 opts->pnp_string = kstrdup(iPNPstring, GFP_KERNEL);
 153                 if (!opts->pnp_string) {
 154                         ret = -ENOMEM;
 155                         goto fail_put_func_inst;
 156                 }
 157                 opts->pnp_string_allocated = true;
 158                 /*
 159                  * we don't free this memory in case of error
 160                  * as printer cleanup func will do this for us
 161                  */
 162         } else {
 163                 opts->pnp_string = pnp_string;
 164         }
 165
 166         ret = usb_string_ids_tab(cdev, strings);
 167         if (ret < 0)
 168                 goto fail_put_func_inst;
 169
 170         device_desc.iManufacturer = strings[USB_GADGET_MANUFACTURER_IDX].id;
 171         device_desc.iProduct = strings[USB_GADGET_PRODUCT_IDX].id;
 172         device_desc.iSerialNumber = strings[USB_GADGET_SERIAL_IDX].id;
 173
 174         if (gadget_is_otg(cdev->gadget) && !otg_desc[0]) {
 175                 struct usb_descriptor_header *usb_desc;
 176
 177                 usb_desc = usb_otg_descriptor_alloc(cdev->gadget);
 178                 if (!usb_desc) {
 179                         ret = -ENOMEM;
 180                         goto fail_put_func_inst;
 181                 }
 182                 usb_otg_descriptor_init(cdev->gadget, usb_desc);
 183                 otg_desc[0] = usb_desc;
 184                 otg_desc[1] = NULL;
 185         }
 186
 187         ret = usb_add_config(cdev, &printer_cfg_driver, printer_do_config);
 188         if (ret)
 189                 goto fail_free_otg_desc;
 190
 191         usb_composite_overwrite_options(cdev, &coverwrite);
 192         return ret;
 193
 194 fail_free_otg_desc:
 195         kfree(otg_desc[0]);
 196         otg_desc[0] = NULL;
 197 fail_put_func_inst:
 198         usb_put_function_instance(fi_printer);
 199         return ret;
 200 }
 201
 202 static int printer_unbind(struct usb_composite_dev *cdev)
 203 {
 204         usb_put_function(f_printer);
 205         usb_put_function_instance(fi_printer);
 206
 207         kfree(otg_desc[0]);
 208         otg_desc[0] = NULL;
 209
 210         return 0;
 211 }
 212
 213 static struct usb_composite_driver printer_driver = {
 214         .name           = shortname,
 215         .dev            = &device_desc,
 216         .strings        = dev_strings,
 217         .max_speed      = USB_SPEED_SUPER,
 218         .bind           = printer_bind,
 219         .unbind         = printer_unbind,
 220 };
 221
 222 module_usb_composite_driver(printer_driver);
 223
 224 MODULE_DESCRIPTION(DRIVER_DESC);
 225 MODULE_AUTHOR("Craig Nadler");
 226 MODULE_LICENSE("GPL");