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_acm.c"
  40 #include "f_obex.c"
  41 #include "f_serial.c"
  42 #include "u_serial.c"
  43
  44 /*-------------------------------------------------------------------------*/
  45 USB_GADGET_COMPOSITE_OPTIONS();
  46
  47 /* Thanks to NetChip Technologies for donating this product ID.
  48 *
  49 * DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
  50 * Instead:  allocate your own, using normal USB-IF procedures.
  51 */
  52 #define GS_VENDOR_ID                    0x0525  /* NetChip */
  53 #define GS_PRODUCT_ID                   0xa4a6  /* Linux-USB Serial Gadget */
  54 #define GS_CDC_PRODUCT_ID               0xa4a7  /* ... as CDC-ACM */
  55 #define GS_CDC_OBEX_PRODUCT_ID          0xa4a9  /* ... as CDC-OBEX */
  56
  57 /* string IDs are assigned dynamically */
  58
  59 #define STRING_DESCRIPTION_IDX          USB_GADGET_FIRST_AVAIL_IDX
  60
  61 static struct usb_string strings_dev[] = {
  62         [USB_GADGET_MANUFACTURER_IDX].s = "",
  63         [USB_GADGET_PRODUCT_IDX].s = GS_VERSION_NAME,
  64         [USB_GADGET_SERIAL_IDX].s = "",
  65         [STRING_DESCRIPTION_IDX].s = NULL /* updated; f(use_acm) */,
  66         {  } /* end of list */
  67 };
  68
  69 static struct usb_gadget_strings stringtab_dev = {
  70         .language       = 0x0409,       /* en-us */
  71         .strings        = strings_dev,
  72 };
  73
  74 static struct usb_gadget_strings *dev_strings[] = {
  75         &stringtab_dev,
  76         NULL,
  77 };
  78
  79 static struct usb_device_descriptor device_desc = {
  80         .bLength =              USB_DT_DEVICE_SIZE,
  81         .bDescriptorType =      USB_DT_DEVICE,
  82         .bcdUSB =               cpu_to_le16(0x0200),
  83         /* .bDeviceClass = f(use_acm) */
  84         .bDeviceSubClass =      0,
  85         .bDeviceProtocol =      0,
  86         /* .bMaxPacketSize0 = f(hardware) */
  87         .idVendor =             cpu_to_le16(GS_VENDOR_ID),
  88         /* .idProduct = f(use_acm) */
  89         .bcdDevice = cpu_to_le16(GS_VERSION_NUM),
  90         /* .iManufacturer = DYNAMIC */
  91         /* .iProduct = DYNAMIC */
  92         .bNumConfigurations =   1,
  93 };
  94
  95 static struct usb_otg_descriptor otg_descriptor = {
  96         .bLength =              sizeof otg_descriptor,
  97         .bDescriptorType =      USB_DT_OTG,
  98
  99         /* REVISIT SRP-only hardware is possible, although
 100          * it would not be called "OTG" ...
 101          */
 102         .bmAttributes =         USB_OTG_SRP | USB_OTG_HNP,
 103 };
 104
 105 static const struct usb_descriptor_header *otg_desc[] = {
 106         (struct usb_descriptor_header *) &otg_descriptor,
 107         NULL,
 108 };
 109
 110 /*-------------------------------------------------------------------------*/
 111
 112 /* Module */
 113 MODULE_DESCRIPTION(GS_VERSION_NAME);
 114 MODULE_AUTHOR("Al Borchers");
 115 MODULE_AUTHOR("David Brownell");
 116 MODULE_LICENSE("GPL");
 117
 118 static bool use_acm = true;
 119 module_param(use_acm, bool, 0);
 120 MODULE_PARM_DESC(use_acm, "Use CDC ACM, default=yes");
 121
 122 static bool use_obex = false;
 123 module_param(use_obex, bool, 0);
 124 MODULE_PARM_DESC(use_obex, "Use CDC OBEX, default=no");
 125
 126 static unsigned n_ports = 1;
 127 module_param(n_ports, uint, 0);
 128 MODULE_PARM_DESC(n_ports, "number of ports to create, default=1");
 129
 130 /*-------------------------------------------------------------------------*/
 131
 132 static int __init serial_bind_config(struct usb_configuration *c)
 133 {
 134         unsigned i;
 135         int status = 0;
 136
 137         for (i = 0; i < n_ports && status == 0; i++) {
 138                 if (use_acm)
 139                         status = acm_bind_config(c, i);
 140                 else if (use_obex)
 141                         status = obex_bind_config(c, i);
 142                 else
 143                         status = gser_bind_config(c, i);
 144         }
 145         return status;
 146 }
 147
 148 static struct usb_configuration serial_config_driver = {
 149         /* .label = f(use_acm) */
 150         /* .bConfigurationValue = f(use_acm) */
 151         /* .iConfiguration = DYNAMIC */
 152         .bmAttributes   = USB_CONFIG_ATT_SELFPOWER,
 153 };
 154
 155 static int __init gs_bind(struct usb_composite_dev *cdev)
 156 {
 157         int                     status;
 158
 159         status = gserial_setup(cdev->gadget, n_ports);
 160         if (status < 0)
 161                 return status;
 162
 163         /* Allocate string descriptor numbers ... note that string
 164          * contents can be overridden by the composite_dev glue.
 165          */
 166
 167         status = usb_string_ids_tab(cdev, strings_dev);
 168         if (status < 0)
 169                 goto fail;
 170         device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
 171         device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
 172         status = strings_dev[STRING_DESCRIPTION_IDX].id;
 173         serial_config_driver.iConfiguration = status;
 174
 175         if (gadget_is_otg(cdev->gadget)) {
 176                 serial_config_driver.descriptors = otg_desc;
 177                 serial_config_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 178         }
 179
 180         /* register our configuration */
 181         status = usb_add_config(cdev, &serial_config_driver,
 182                         serial_bind_config);
 183         if (status < 0)
 184                 goto fail;
 185
 186         usb_composite_overwrite_options(cdev, &coverwrite);
 187         INFO(cdev, "%s\n", GS_VERSION_NAME);
 188
 189         return 0;
 190
 191 fail:
 192         gserial_cleanup();
 193         return status;
 194 }
 195
 196 static __refdata struct usb_composite_driver gserial_driver = {
 197         .name           = "g_serial",
 198         .dev            = &device_desc,
 199         .strings        = dev_strings,
 200         .max_speed      = USB_SPEED_SUPER,
 201         .bind           = gs_bind,
 202 };
 203
 204 static int __init init(void)
 205 {
 206         /* We *could* export two configs; that'd be much cleaner...
 207          * but neither of these product IDs was defined that way.
 208          */
 209         if (use_acm) {
 210                 serial_config_driver.label = "CDC ACM config";
 211                 serial_config_driver.bConfigurationValue = 2;
 212                 device_desc.bDeviceClass = USB_CLASS_COMM;
 213                 device_desc.idProduct =
 214                                 cpu_to_le16(GS_CDC_PRODUCT_ID);
 215         } else if (use_obex) {
 216                 serial_config_driver.label = "CDC OBEX config";
 217                 serial_config_driver.bConfigurationValue = 3;
 218                 device_desc.bDeviceClass = USB_CLASS_COMM;
 219                 device_desc.idProduct =
 220                         cpu_to_le16(GS_CDC_OBEX_PRODUCT_ID);
 221         } else {
 222                 serial_config_driver.label = "Generic Serial config";
 223                 serial_config_driver.bConfigurationValue = 1;
 224                 device_desc.bDeviceClass = USB_CLASS_VENDOR_SPEC;
 225                 device_desc.idProduct =
 226                                 cpu_to_le16(GS_PRODUCT_ID);
 227         }
 228         strings_dev[STRING_DESCRIPTION_IDX].s = serial_config_driver.label;
 229
 230         return usb_composite_probe(&gserial_driver);
 231 }
 232 module_init(init);
 233
 234 static void __exit cleanup(void)
 235 {
 236         usb_composite_unregister(&gserial_driver);
 237         gserial_cleanup();
 238 }
 239 module_exit(cleanup);