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