drivers/usb/gadget/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/tty.h>
  16 #include <linux/tty_flip.h>
  17
  18 #include "u_serial.h"
  19 #include "gadget_chips.h"
  20
  21
  22 /* Defines */
  23
  24 #define GS_VERSION_STR                  "v2.4"
  25 #define GS_VERSION_NUM                  0x2400
  26
  27 #define GS_LONG_NAME                    "Gadget Serial"
  28 #define GS_VERSION_NAME                 GS_LONG_NAME " " GS_VERSION_STR
  29
  30 /*-------------------------------------------------------------------------*/
  31
  32 /*
  33  * Kbuild is not very cooperative with respect to linking separately
  34  * compiled library objects into one module.  So for now we won't use
  35  * separate compilation ... ensuring init/exit sections work to shrink
  36  * the runtime footprint, and giving us at least some parts of what
  37  * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
  38  */
  39 #include "f_obex.c"
  40
  41 /*-------------------------------------------------------------------------*/
  42 USB_GADGET_COMPOSITE_OPTIONS();
  43
  44 /* Thanks to NetChip Technologies for donating this product ID.
  45 *
  46 * DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
  47 * Instead:  allocate your own, using normal USB-IF procedures.
  48 */
  49 #define GS_VENDOR_ID                    0x0525  /* NetChip */
  50 #define GS_PRODUCT_ID                   0xa4a6  /* Linux-USB Serial Gadget */
  51 #define GS_CDC_PRODUCT_ID               0xa4a7  /* ... as CDC-ACM */
  52 #define GS_CDC_OBEX_PRODUCT_ID          0xa4a9  /* ... as CDC-OBEX */
  53
  54 /* string IDs are assigned dynamically */
  55
  56 #define STRING_DESCRIPTION_IDX          USB_GADGET_FIRST_AVAIL_IDX
  57
  58 static struct usb_string strings_dev[] = {
  59         [USB_GADGET_MANUFACTURER_IDX].s = "",
  60         [USB_GADGET_PRODUCT_IDX].s = GS_VERSION_NAME,
  61         [USB_GADGET_SERIAL_IDX].s = "",
  62         [STRING_DESCRIPTION_IDX].s = NULL /* updated; f(use_acm) */,
  63         {  } /* end of list */
  64 };
  65
  66 static struct usb_gadget_strings stringtab_dev = {
  67         .language       = 0x0409,       /* en-us */
  68         .strings        = strings_dev,
  69 };
  70
  71 static struct usb_gadget_strings *dev_strings[] = {
  72         &stringtab_dev,
  73         NULL,
  74 };
  75
  76 static struct usb_device_descriptor device_desc = {
  77         .bLength =              USB_DT_DEVICE_SIZE,
  78         .bDescriptorType =      USB_DT_DEVICE,
  79         .bcdUSB =               cpu_to_le16(0x0200),
  80         /* .bDeviceClass = f(use_acm) */
  81         .bDeviceSubClass =      0,
  82         .bDeviceProtocol =      0,
  83         /* .bMaxPacketSize0 = f(hardware) */
  84         .idVendor =             cpu_to_le16(GS_VENDOR_ID),
  85         /* .idProduct = f(use_acm) */
  86         .bcdDevice = cpu_to_le16(GS_VERSION_NUM),
  87         /* .iManufacturer = DYNAMIC */
  88         /* .iProduct = DYNAMIC */
  89         .bNumConfigurations =   1,
  90 };
  91
  92 static struct usb_otg_descriptor otg_descriptor = {
  93         .bLength =              sizeof otg_descriptor,
  94         .bDescriptorType =      USB_DT_OTG,
  95
  96         /* REVISIT SRP-only hardware is possible, although
  97          * it would not be called "OTG" ...
  98          */
  99         .bmAttributes =         USB_OTG_SRP | USB_OTG_HNP,
 100 };
 101
 102 static const struct usb_descriptor_header *otg_desc[] = {
 103         (struct usb_descriptor_header *) &otg_descriptor,
 104         NULL,
 105 };
 106
 107 /*-------------------------------------------------------------------------*/
 108
 109 /* Module */
 110 MODULE_DESCRIPTION(GS_VERSION_NAME);
 111 MODULE_AUTHOR("Al Borchers");
 112 MODULE_AUTHOR("David Brownell");
 113 MODULE_LICENSE("GPL");
 114
 115 static bool use_acm = true;
 116 module_param(use_acm, bool, 0);
 117 MODULE_PARM_DESC(use_acm, "Use CDC ACM, default=yes");
 118
 119 static bool use_obex = false;
 120 module_param(use_obex, bool, 0);
 121 MODULE_PARM_DESC(use_obex, "Use CDC OBEX, default=no");
 122
 123 static unsigned n_ports = 1;
 124 module_param(n_ports, uint, 0);
 125 MODULE_PARM_DESC(n_ports, "number of ports to create, default=1");
 126
 127 /*-------------------------------------------------------------------------*/
 128 static unsigned char tty_lines[MAX_U_SERIAL_PORTS];
 129
 130 static int __init serial_bind_obex_config(struct usb_configuration *c)
 131 {
 132         unsigned i;
 133         int status = 0;
 134
 135         for (i = 0; i < n_ports && status == 0; i++)
 136                 status = obex_bind_config(c, tty_lines[i]);
 137         return status;
 138 }
 139
 140 static struct usb_configuration serial_config_driver = {
 141         /* .label = f(use_acm) */
 142         /* .bConfigurationValue = f(use_acm) */
 143         /* .iConfiguration = DYNAMIC */
 144         .bmAttributes   = USB_CONFIG_ATT_SELFPOWER,
 145 };
 146
 147 static struct usb_function_instance *fi_serial[MAX_U_SERIAL_PORTS];
 148 static struct usb_function *f_serial[MAX_U_SERIAL_PORTS];
 149
 150 static int serial_register_ports(struct usb_composite_dev *cdev,
 151                 struct usb_configuration *c, const char *f_name)
 152 {
 153         int i;
 154         int ret;
 155
 156         ret = usb_add_config_only(cdev, c);
 157         if (ret)
 158                 goto out;
 159
 160         for (i = 0; i < n_ports; i++) {
 161
 162                 fi_serial[i] = usb_get_function_instance(f_name);
 163                 if (IS_ERR(fi_serial[i])) {
 164                         ret = PTR_ERR(fi_serial[i]);
 165                         goto fail;
 166                 }
 167
 168                 f_serial[i] = usb_get_function(fi_serial[i]);
 169                 if (IS_ERR(f_serial[i])) {
 170                         ret = PTR_ERR(f_serial[i]);
 171                         goto err_get_func;
 172                 }
 173
 174                 ret = usb_add_function(c, f_serial[i]);
 175                 if (ret)
 176                         goto err_add_func;
 177         }
 178
 179         return 0;
 180
 181 err_add_func:
 182         usb_put_function(f_serial[i]);
 183 err_get_func:
 184         usb_put_function_instance(fi_serial[i]);
 185
 186 fail:
 187         i--;
 188         while (i >= 0) {
 189                 usb_remove_function(c, f_serial[i]);
 190                 usb_put_function(f_serial[i]);
 191                 usb_put_function_instance(fi_serial[i]);
 192                 i--;
 193         }
 194 out:
 195         return ret;
 196 }
 197
 198 static int __init gs_bind(struct usb_composite_dev *cdev)
 199 {
 200         int                     status;
 201         int                     cur_line = 0;
 202
 203         if (use_obex) {
 204                 for (cur_line = 0; cur_line < n_ports; cur_line++) {
 205                         status = gserial_alloc_line(&tty_lines[cur_line]);
 206                         if (status)
 207                                 goto fail;
 208                 }
 209         }
 210
 211         /* Allocate string descriptor numbers ... note that string
 212          * contents can be overridden by the composite_dev glue.
 213          */
 214
 215         status = usb_string_ids_tab(cdev, strings_dev);
 216         if (status < 0)
 217                 goto fail;
 218         device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
 219         device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
 220         status = strings_dev[STRING_DESCRIPTION_IDX].id;
 221         serial_config_driver.iConfiguration = status;
 222
 223         if (gadget_is_otg(cdev->gadget)) {
 224                 serial_config_driver.descriptors = otg_desc;
 225                 serial_config_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 226         }
 227
 228         /* register our configuration */
 229         if (use_acm) {
 230                 status  = serial_register_ports(cdev, &serial_config_driver,
 231                                 "acm");
 232                 usb_ep_autoconfig_reset(cdev->gadget);
 233         } else if (use_obex)
 234                 status = usb_add_config(cdev, &serial_config_driver,
 235                                 serial_bind_obex_config);
 236         else {
 237                 status = serial_register_ports(cdev, &serial_config_driver,
 238                                 "gser");
 239         }
 240         if (status < 0)
 241                 goto fail;
 242
 243         usb_composite_overwrite_options(cdev, &coverwrite);
 244         INFO(cdev, "%s\n", GS_VERSION_NAME);
 245
 246         return 0;
 247
 248 fail:
 249         cur_line--;
 250         while (cur_line >= 0 && use_obex)
 251                 gserial_free_line(tty_lines[cur_line--]);
 252         return status;
 253 }
 254
 255 static int gs_unbind(struct usb_composite_dev *cdev)
 256 {
 257         int i;
 258
 259         for (i = 0; i < n_ports; i++) {
 260                 usb_put_function(f_serial[i]);
 261                 usb_put_function_instance(fi_serial[i]);
 262                 if (use_obex)
 263                         gserial_free_line(tty_lines[i]);
 264         }
 265         return 0;
 266 }
 267
 268 static __refdata struct usb_composite_driver gserial_driver = {
 269         .name           = "g_serial",
 270         .dev            = &device_desc,
 271         .strings        = dev_strings,
 272         .max_speed      = USB_SPEED_SUPER,
 273         .bind           = gs_bind,
 274         .unbind         = gs_unbind,
 275 };
 276
 277 static int __init init(void)
 278 {
 279         /* We *could* export two configs; that'd be much cleaner...
 280          * but neither of these product IDs was defined that way.
 281          */
 282         if (use_acm) {
 283                 serial_config_driver.label = "CDC ACM config";
 284                 serial_config_driver.bConfigurationValue = 2;
 285                 device_desc.bDeviceClass = USB_CLASS_COMM;
 286                 device_desc.idProduct =
 287                                 cpu_to_le16(GS_CDC_PRODUCT_ID);
 288         } else if (use_obex) {
 289                 serial_config_driver.label = "CDC OBEX config";
 290                 serial_config_driver.bConfigurationValue = 3;
 291                 device_desc.bDeviceClass = USB_CLASS_COMM;
 292                 device_desc.idProduct =
 293                         cpu_to_le16(GS_CDC_OBEX_PRODUCT_ID);
 294         } else {
 295                 serial_config_driver.label = "Generic Serial config";
 296                 serial_config_driver.bConfigurationValue = 1;
 297                 device_desc.bDeviceClass = USB_CLASS_VENDOR_SPEC;
 298                 device_desc.idProduct =
 299                                 cpu_to_le16(GS_PRODUCT_ID);
 300         }
 301         strings_dev[STRING_DESCRIPTION_IDX].s = serial_config_driver.label;
 302
 303         return usb_composite_probe(&gserial_driver);
 304 }
 305 module_init(init);
 306
 307 static void __exit cleanup(void)
 308 {
 309         usb_composite_unregister(&gserial_driver);
 310 }
 311 module_exit(cleanup);