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/utsname.h>
  15 #include <linux/device.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
  33 /*
  34  * Kbuild is not very cooperative with respect to linking separately
  35  * compiled library objects into one module.  So for now we won't use
  36  * separate compilation ... ensuring init/exit sections work to shrink
  37  * the runtime footprint, and giving us at least some parts of what
  38  * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
  39  */
  40 #include "composite.c"
  41 #include "usbstring.c"
  42 #include "config.c"
  43 #include "epautoconf.c"
  44
  45 #include "f_acm.c"
  46 #include "f_obex.c"
  47 #include "f_serial.c"
  48 #include "u_serial.c"
  49
  50 /*-------------------------------------------------------------------------*/
  51
  52 /* Thanks to NetChip Technologies for donating this product ID.
  53 *
  54 * DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
  55 * Instead:  allocate your own, using normal USB-IF procedures.
  56 */
  57 #define GS_VENDOR_ID                    0x0525  /* NetChip */
  58 #define GS_PRODUCT_ID                   0xa4a6  /* Linux-USB Serial Gadget */
  59 #define GS_CDC_PRODUCT_ID               0xa4a7  /* ... as CDC-ACM */
  60 #define GS_CDC_OBEX_PRODUCT_ID          0xa4a9  /* ... as CDC-OBEX */
  61
  62 /* string IDs are assigned dynamically */
  63
  64 #define STRING_MANUFACTURER_IDX         0
  65 #define STRING_PRODUCT_IDX              1
  66 #define STRING_DESCRIPTION_IDX          2
  67
  68 static char manufacturer[50];
  69
  70 static struct usb_string strings_dev[] = {
  71         [STRING_MANUFACTURER_IDX].s = manufacturer,
  72         [STRING_PRODUCT_IDX].s = GS_VERSION_NAME,
  73         [STRING_DESCRIPTION_IDX].s = NULL /* updated; f(use_acm) */,
  74         {  } /* end of list */
  75 };
  76
  77 static struct usb_gadget_strings stringtab_dev = {
  78         .language       = 0x0409,       /* en-us */
  79         .strings        = strings_dev,
  80 };
  81
  82 static struct usb_gadget_strings *dev_strings[] = {
  83         &stringtab_dev,
  84         NULL,
  85 };
  86
  87 static struct usb_device_descriptor device_desc = {
  88         .bLength =              USB_DT_DEVICE_SIZE,
  89         .bDescriptorType =      USB_DT_DEVICE,
  90         .bcdUSB =               cpu_to_le16(0x0200),
  91         /* .bDeviceClass = f(use_acm) */
  92         .bDeviceSubClass =      0,
  93         .bDeviceProtocol =      0,
  94         /* .bMaxPacketSize0 = f(hardware) */
  95         .idVendor =             cpu_to_le16(GS_VENDOR_ID),
  96         /* .idProduct = f(use_acm) */
  97         /* .bcdDevice = f(hardware) */
  98         /* .iManufacturer = DYNAMIC */
  99         /* .iProduct = DYNAMIC */
 100         .bNumConfigurations =   1,
 101 };
 102
 103 static struct usb_otg_descriptor otg_descriptor = {
 104         .bLength =              sizeof otg_descriptor,
 105         .bDescriptorType =      USB_DT_OTG,
 106
 107         /* REVISIT SRP-only hardware is possible, although
 108          * it would not be called "OTG" ...
 109          */
 110         .bmAttributes =         USB_OTG_SRP | USB_OTG_HNP,
 111 };
 112
 113 static const struct usb_descriptor_header *otg_desc[] = {
 114         (struct usb_descriptor_header *) &otg_descriptor,
 115         NULL,
 116 };
 117
 118 /*-------------------------------------------------------------------------*/
 119
 120 /* Module */
 121 MODULE_DESCRIPTION(GS_VERSION_NAME);
 122 MODULE_AUTHOR("Al Borchers");
 123 MODULE_AUTHOR("David Brownell");
 124 MODULE_LICENSE("GPL");
 125
 126 static int use_acm = true;
 127 module_param(use_acm, bool, 0);
 128 MODULE_PARM_DESC(use_acm, "Use CDC ACM, default=yes");
 129
 130 static int use_obex = false;
 131 module_param(use_obex, bool, 0);
 132 MODULE_PARM_DESC(use_obex, "Use CDC OBEX, default=no");
 133
 134 static unsigned n_ports = 1;
 135 module_param(n_ports, uint, 0);
 136 MODULE_PARM_DESC(n_ports, "number of ports to create, default=1");
 137
 138 /*-------------------------------------------------------------------------*/
 139
 140 static int __ref serial_bind_config(struct usb_configuration *c)
 141 {
 142         unsigned i;
 143         int status = 0;
 144
 145         for (i = 0; i < n_ports && status == 0; i++) {
 146                 if (use_acm)
 147                         status = acm_bind_config(c, i);
 148                 else if (use_obex)
 149                         status = obex_bind_config(c, i);
 150                 else
 151                         status = gser_bind_config(c, i);
 152         }
 153         return status;
 154 }
 155
 156 static struct usb_configuration serial_config_driver = {
 157         /* .label = f(use_acm) */
 158         .bind           = serial_bind_config,
 159         /* .bConfigurationValue = f(use_acm) */
 160         /* .iConfiguration = DYNAMIC */
 161         .bmAttributes   = USB_CONFIG_ATT_SELFPOWER,
 162 };
 163
 164 static int __ref gs_bind(struct usb_composite_dev *cdev)
 165 {
 166         int                     gcnum;
 167         struct usb_gadget       *gadget = cdev->gadget;
 168         int                     status;
 169
 170         status = gserial_setup(cdev->gadget, n_ports);
 171         if (status < 0)
 172                 return status;
 173
 174         /* Allocate string descriptor numbers ... note that string
 175          * contents can be overridden by the composite_dev glue.
 176          */
 177
 178         /* device description: manufacturer, product */
 179         snprintf(manufacturer, sizeof manufacturer, "%s %s with %s",
 180                 init_utsname()->sysname, init_utsname()->release,
 181                 gadget->name);
 182         status = usb_string_id(cdev);
 183         if (status < 0)
 184                 goto fail;
 185         strings_dev[STRING_MANUFACTURER_IDX].id = status;
 186
 187         device_desc.iManufacturer = status;
 188
 189         status = usb_string_id(cdev);
 190         if (status < 0)
 191                 goto fail;
 192         strings_dev[STRING_PRODUCT_IDX].id = status;
 193
 194         device_desc.iProduct = status;
 195
 196         /* config description */
 197         status = usb_string_id(cdev);
 198         if (status < 0)
 199                 goto fail;
 200         strings_dev[STRING_DESCRIPTION_IDX].id = status;
 201
 202         serial_config_driver.iConfiguration = status;
 203
 204         /* set up other descriptors */
 205         gcnum = usb_gadget_controller_number(gadget);
 206         if (gcnum >= 0)
 207                 device_desc.bcdDevice = cpu_to_le16(GS_VERSION_NUM | gcnum);
 208         else {
 209                 /* this is so simple (for now, no altsettings) that it
 210                  * SHOULD NOT have problems with bulk-capable hardware.
 211                  * so warn about unrcognized controllers -- don't panic.
 212                  *
 213                  * things like configuration and altsetting numbering
 214                  * can need hardware-specific attention though.
 215                  */
 216                 pr_warning("gs_bind: controller '%s' not recognized\n",
 217                         gadget->name);
 218                 device_desc.bcdDevice =
 219                         cpu_to_le16(GS_VERSION_NUM | 0x0099);
 220         }
 221
 222         if (gadget_is_otg(cdev->gadget)) {
 223                 serial_config_driver.descriptors = otg_desc;
 224                 serial_config_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 225         }
 226
 227         /* register our configuration */
 228         status = usb_add_config(cdev, &serial_config_driver);
 229         if (status < 0)
 230                 goto fail;
 231
 232         INFO(cdev, "%s\n", GS_VERSION_NAME);
 233
 234         return 0;
 235
 236 fail:
 237         gserial_cleanup();
 238         return status;
 239 }
 240
 241 static struct usb_composite_driver gserial_driver = {
 242         .name           = "g_serial",
 243         .dev            = &device_desc,
 244         .strings        = dev_strings,
 245         .bind           = gs_bind,
 246 };
 247
 248 static int __init init(void)
 249 {
 250         /* We *could* export two configs; that'd be much cleaner...
 251          * but neither of these product IDs was defined that way.
 252          */
 253         if (use_acm) {
 254                 serial_config_driver.label = "CDC ACM config";
 255                 serial_config_driver.bConfigurationValue = 2;
 256                 device_desc.bDeviceClass = USB_CLASS_COMM;
 257                 device_desc.idProduct =
 258                                 cpu_to_le16(GS_CDC_PRODUCT_ID);
 259         } else if (use_obex) {
 260                 serial_config_driver.label = "CDC OBEX config";
 261                 serial_config_driver.bConfigurationValue = 3;
 262                 device_desc.bDeviceClass = USB_CLASS_COMM;
 263                 device_desc.idProduct =
 264                         cpu_to_le16(GS_CDC_OBEX_PRODUCT_ID);
 265         } else {
 266                 serial_config_driver.label = "Generic Serial config";
 267                 serial_config_driver.bConfigurationValue = 1;
 268                 device_desc.bDeviceClass = USB_CLASS_VENDOR_SPEC;
 269                 device_desc.idProduct =
 270                                 cpu_to_le16(GS_PRODUCT_ID);
 271         }
 272         strings_dev[STRING_DESCRIPTION_IDX].s = serial_config_driver.label;
 273
 274         return usb_composite_register(&gserial_driver);
 275 }
 276 module_init(init);
 277
 278 static void __exit cleanup(void)
 279 {
 280         usb_composite_unregister(&gserial_driver);
 281         gserial_cleanup();
 282 }
 283 module_exit(cleanup);