drivers/usb/gadget/legacy/serial.c

   1 /*
   2  * serial.c -- USB gadget serial driver
   3  *
   4  * Copyright (C) 2003 Al Borchers (alborchers@steinerpoint.com)
   5  * Copyright (C) 2008 by David Brownell
   6  * Copyright (C) 2008 by Nokia Corporation
   7  *
   8  * This software is distributed under the terms of the GNU General
   9  * Public License ("GPL") as published by the Free Software Foundation,
  10  * either version 2 of that License or (at your option) any later version.
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/device.h>
  15 #include <linux/module.h>
  16 #include <linux/tty.h>
  17 #include <linux/tty_flip.h>
  18
  19 #include "u_serial.h"
  20 #include "gadget_chips.h"
  21
  22
  23 /* Defines */
  24
  25 #define GS_VERSION_STR                  "v2.4"
  26 #define GS_VERSION_NUM                  0x2400
  27
  28 #define GS_LONG_NAME                    "Gadget Serial"
  29 #define GS_VERSION_NAME                 GS_LONG_NAME " " GS_VERSION_STR
  30
  31 /*-------------------------------------------------------------------------*/
  32 USB_GADGET_COMPOSITE_OPTIONS();
  33
  34 /* Thanks to NetChip Technologies for donating this product ID.
  35 *
  36 * DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
  37 * Instead:  allocate your own, using normal USB-IF procedures.
  38 */
  39 #define GS_VENDOR_ID                    0x0525  /* NetChip */
  40 #define GS_PRODUCT_ID                   0xa4a6  /* Linux-USB Serial Gadget */
  41 #define GS_CDC_PRODUCT_ID               0xa4a7  /* ... as CDC-ACM */
  42 #define GS_CDC_OBEX_PRODUCT_ID          0xa4a9  /* ... as CDC-OBEX */
  43
  44 /* string IDs are assigned dynamically */
  45
  46 #define STRING_DESCRIPTION_IDX          USB_GADGET_FIRST_AVAIL_IDX
  47
  48 static struct usb_string strings_dev[] = {
  49         [USB_GADGET_MANUFACTURER_IDX].s = "",
  50         [USB_GADGET_PRODUCT_IDX].s = GS_VERSION_NAME,
  51         [USB_GADGET_SERIAL_IDX].s = "",
  52         [STRING_DESCRIPTION_IDX].s = NULL /* updated; f(use_acm) */,
  53         {  } /* end of list */
  54 };
  55
  56 static struct usb_gadget_strings stringtab_dev = {
  57         .language       = 0x0409,       /* en-us */
  58         .strings        = strings_dev,
  59 };
  60
  61 static struct usb_gadget_strings *dev_strings[] = {
  62         &stringtab_dev,
  63         NULL,
  64 };
  65
  66 static struct usb_device_descriptor device_desc = {
  67         .bLength =              USB_DT_DEVICE_SIZE,
  68         .bDescriptorType =      USB_DT_DEVICE,
  69         .bcdUSB =               cpu_to_le16(0x0200),
  70         /* .bDeviceClass = f(use_acm) */
  71         .bDeviceSubClass =      0,
  72         .bDeviceProtocol =      0,
  73         /* .bMaxPacketSize0 = f(hardware) */
  74         .idVendor =             cpu_to_le16(GS_VENDOR_ID),
  75         /* .idProduct = f(use_acm) */
  76         .bcdDevice = cpu_to_le16(GS_VERSION_NUM),
  77         /* .iManufacturer = DYNAMIC */
  78         /* .iProduct = DYNAMIC */
  79         .bNumConfigurations =   1,
  80 };
  81
  82 static struct usb_otg_descriptor otg_descriptor = {
  83         .bLength =              sizeof otg_descriptor,
  84         .bDescriptorType =      USB_DT_OTG,
  85
  86         /* REVISIT SRP-only hardware is possible, although
  87          * it would not be called "OTG" ...
  88          */
  89         .bmAttributes =         USB_OTG_SRP | USB_OTG_HNP,
  90 };
  91
  92 static const struct usb_descriptor_header *otg_desc[] = {
  93         (struct usb_descriptor_header *) &otg_descriptor,
  94         NULL,
  95 };
  96
  97 /*-------------------------------------------------------------------------*/
  98
  99 /* Module */
 100 MODULE_DESCRIPTION(GS_VERSION_NAME);
 101 MODULE_AUTHOR("Al Borchers");
 102 MODULE_AUTHOR("David Brownell");
 103 MODULE_LICENSE("GPL");
 104
 105 static bool use_acm = true;
 106 module_param(use_acm, bool, 0);
 107 MODULE_PARM_DESC(use_acm, "Use CDC ACM, default=yes");
 108
 109 static bool use_obex = false;
 110 module_param(use_obex, bool, 0);
 111 MODULE_PARM_DESC(use_obex, "Use CDC OBEX, default=no");
 112
 113 static unsigned n_ports = 1;
 114 module_param(n_ports, uint, 0);
 115 MODULE_PARM_DESC(n_ports, "number of ports to create, default=1");
 116
 117 /*-------------------------------------------------------------------------*/
 118
 119 static struct usb_configuration serial_config_driver = {
 120         /* .label = f(use_acm) */
 121         /* .bConfigurationValue = f(use_acm) */
 122         /* .iConfiguration = DYNAMIC */
 123         .bmAttributes   = USB_CONFIG_ATT_SELFPOWER,
 124 };
 125
 126 static struct usb_function_instance *fi_serial[MAX_U_SERIAL_PORTS];
 127 static struct usb_function *f_serial[MAX_U_SERIAL_PORTS];
 128
 129 static int serial_register_ports(struct usb_composite_dev *cdev,
 130                 struct usb_configuration *c, const char *f_name)
 131 {
 132         int i;
 133         int ret;
 134
 135         ret = usb_add_config_only(cdev, c);
 136         if (ret)
 137                 goto out;
 138
 139         for (i = 0; i < n_ports; i++) {
 140
 141                 fi_serial[i] = usb_get_function_instance(f_name);
 142                 if (IS_ERR(fi_serial[i])) {
 143                         ret = PTR_ERR(fi_serial[i]);
 144                         goto fail;
 145                 }
 146
 147                 f_serial[i] = usb_get_function(fi_serial[i]);
 148                 if (IS_ERR(f_serial[i])) {
 149                         ret = PTR_ERR(f_serial[i]);
 150                         goto err_get_func;
 151                 }
 152
 153                 ret = usb_add_function(c, f_serial[i]);
 154                 if (ret)
 155                         goto err_add_func;
 156         }
 157
 158         return 0;
 159
 160 err_add_func:
 161         usb_put_function(f_serial[i]);
 162 err_get_func:
 163         usb_put_function_instance(fi_serial[i]);
 164
 165 fail:
 166         i--;
 167         while (i >= 0) {
 168                 usb_remove_function(c, f_serial[i]);
 169                 usb_put_function(f_serial[i]);
 170                 usb_put_function_instance(fi_serial[i]);
 171                 i--;
 172         }
 173 out:
 174         return ret;
 175 }
 176
 177 static int gs_bind(struct usb_composite_dev *cdev)
 178 {
 179         int                     status;
 180
 181         /* Allocate string descriptor numbers ... note that string
 182          * contents can be overridden by the composite_dev glue.
 183          */
 184
 185         status = usb_string_ids_tab(cdev, strings_dev);
 186         if (status < 0)
 187                 goto fail;
 188         device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
 189         device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
 190         status = strings_dev[STRING_DESCRIPTION_IDX].id;
 191         serial_config_driver.iConfiguration = status;
 192
 193         if (gadget_is_otg(cdev->gadget)) {
 194                 serial_config_driver.descriptors = otg_desc;
 195                 serial_config_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 196         }
 197
 198         /* register our configuration */
 199         if (use_acm) {
 200                 status  = serial_register_ports(cdev, &serial_config_driver,
 201                                 "acm");
 202                 usb_ep_autoconfig_reset(cdev->gadget);
 203         } else if (use_obex)
 204                 status = serial_register_ports(cdev, &serial_config_driver,
 205                                 "obex");
 206         else {
 207                 status = serial_register_ports(cdev, &serial_config_driver,
 208                                 "gser");
 209         }
 210         if (status < 0)
 211                 goto fail;
 212
 213         usb_composite_overwrite_options(cdev, &coverwrite);
 214         INFO(cdev, "%s\n", GS_VERSION_NAME);
 215
 216         return 0;
 217
 218 fail:
 219         return status;
 220 }
 221
 222 static int gs_unbind(struct usb_composite_dev *cdev)
 223 {
 224         int i;
 225
 226         for (i = 0; i < n_ports; i++) {
 227                 usb_put_function(f_serial[i]);
 228                 usb_put_function_instance(fi_serial[i]);
 229         }
 230         return 0;
 231 }
 232
 233 static struct usb_composite_driver gserial_driver = {
 234         .name           = "g_serial",
 235         .dev            = &device_desc,
 236         .strings        = dev_strings,
 237         .max_speed      = USB_SPEED_SUPER,
 238         .bind           = gs_bind,
 239         .unbind         = gs_unbind,
 240 };
 241
 242 static int __init init(void)
 243 {
 244         /* We *could* export two configs; that'd be much cleaner...
 245          * but neither of these product IDs was defined that way.
 246          */
 247         if (use_acm) {
 248                 serial_config_driver.label = "CDC ACM config";
 249                 serial_config_driver.bConfigurationValue = 2;
 250                 device_desc.bDeviceClass = USB_CLASS_COMM;
 251                 device_desc.idProduct =
 252                                 cpu_to_le16(GS_CDC_PRODUCT_ID);
 253         } else if (use_obex) {
 254                 serial_config_driver.label = "CDC OBEX config";
 255                 serial_config_driver.bConfigurationValue = 3;
 256                 device_desc.bDeviceClass = USB_CLASS_COMM;
 257                 device_desc.idProduct =
 258                         cpu_to_le16(GS_CDC_OBEX_PRODUCT_ID);
 259         } else {
 260                 serial_config_driver.label = "Generic Serial config";
 261                 serial_config_driver.bConfigurationValue = 1;
 262                 device_desc.bDeviceClass = USB_CLASS_VENDOR_SPEC;
 263                 device_desc.idProduct =
 264                                 cpu_to_le16(GS_PRODUCT_ID);
 265         }
 266         strings_dev[STRING_DESCRIPTION_IDX].s = serial_config_driver.label;
 267
 268         return usb_composite_probe(&gserial_driver);
 269 }
 270 module_init(init);
 271
 272 static void __exit cleanup(void)
 273 {
 274         usb_composite_unregister(&gserial_driver);
 275 }
 276 module_exit(cleanup);