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/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         .bcdOTG =               cpu_to_le16(0x0200),
  91 };
  92
  93 static const struct usb_descriptor_header *otg_desc[] = {
  94         (struct usb_descriptor_header *) &otg_descriptor,
  95         NULL,
  96 };
  97
  98 /*-------------------------------------------------------------------------*/
  99
 100 /* Module */
 101 MODULE_DESCRIPTION(GS_VERSION_NAME);
 102 MODULE_AUTHOR("Al Borchers");
 103 MODULE_AUTHOR("David Brownell");
 104 MODULE_LICENSE("GPL");
 105
 106 static bool use_acm = true;
 107 module_param(use_acm, bool, 0);
 108 MODULE_PARM_DESC(use_acm, "Use CDC ACM, default=yes");
 109
 110 static bool use_obex = false;
 111 module_param(use_obex, bool, 0);
 112 MODULE_PARM_DESC(use_obex, "Use CDC OBEX, default=no");
 113
 114 static unsigned n_ports = 1;
 115 module_param(n_ports, uint, 0);
 116 MODULE_PARM_DESC(n_ports, "number of ports to create, default=1");
 117
 118 /*-------------------------------------------------------------------------*/
 119
 120 static struct usb_configuration serial_config_driver = {
 121         /* .label = f(use_acm) */
 122         /* .bConfigurationValue = f(use_acm) */
 123         /* .iConfiguration = DYNAMIC */
 124         .bmAttributes   = USB_CONFIG_ATT_SELFPOWER,
 125 };
 126
 127 static struct usb_function_instance *fi_serial[MAX_U_SERIAL_PORTS];
 128 static struct usb_function *f_serial[MAX_U_SERIAL_PORTS];
 129
 130 static int serial_register_ports(struct usb_composite_dev *cdev,
 131                 struct usb_configuration *c, const char *f_name)
 132 {
 133         int i;
 134         int ret;
 135
 136         ret = usb_add_config_only(cdev, c);
 137         if (ret)
 138                 goto out;
 139
 140         for (i = 0; i < n_ports; i++) {
 141
 142                 fi_serial[i] = usb_get_function_instance(f_name);
 143                 if (IS_ERR(fi_serial[i])) {
 144                         ret = PTR_ERR(fi_serial[i]);
 145                         goto fail;
 146                 }
 147
 148                 f_serial[i] = usb_get_function(fi_serial[i]);
 149                 if (IS_ERR(f_serial[i])) {
 150                         ret = PTR_ERR(f_serial[i]);
 151                         goto err_get_func;
 152                 }
 153
 154                 ret = usb_add_function(c, f_serial[i]);
 155                 if (ret)
 156                         goto err_add_func;
 157         }
 158
 159         return 0;
 160
 161 err_add_func:
 162         usb_put_function(f_serial[i]);
 163 err_get_func:
 164         usb_put_function_instance(fi_serial[i]);
 165
 166 fail:
 167         i--;
 168         while (i >= 0) {
 169                 usb_remove_function(c, f_serial[i]);
 170                 usb_put_function(f_serial[i]);
 171                 usb_put_function_instance(fi_serial[i]);
 172                 i--;
 173         }
 174 out:
 175         return ret;
 176 }
 177
 178 static int __init gs_bind(struct usb_composite_dev *cdev)
 179 {
 180         int                     status;
 181
 182         /* Allocate string descriptor numbers ... note that string
 183          * contents can be overridden by the composite_dev glue.
 184          */
 185
 186         status = usb_string_ids_tab(cdev, strings_dev);
 187         if (status < 0)
 188                 goto fail;
 189         device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
 190         device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
 191         status = strings_dev[STRING_DESCRIPTION_IDX].id;
 192         serial_config_driver.iConfiguration = status;
 193
 194         if (gadget_is_otg(cdev->gadget)) {
 195                 serial_config_driver.descriptors = otg_desc;
 196                 serial_config_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 197         }
 198
 199         /* register our configuration */
 200         if (use_acm) {
 201                 status  = serial_register_ports(cdev, &serial_config_driver,
 202                                 "acm");
 203                 usb_ep_autoconfig_reset(cdev->gadget);
 204         } else if (use_obex)
 205                 status = serial_register_ports(cdev, &serial_config_driver,
 206                                 "obex");
 207         else {
 208                 status = serial_register_ports(cdev, &serial_config_driver,
 209                                 "gser");
 210         }
 211         if (status < 0)
 212                 goto fail;
 213
 214         usb_composite_overwrite_options(cdev, &coverwrite);
 215         INFO(cdev, "%s\n", GS_VERSION_NAME);
 216
 217         return 0;
 218
 219 fail:
 220         return status;
 221 }
 222
 223 static int gs_unbind(struct usb_composite_dev *cdev)
 224 {
 225         int i;
 226
 227         for (i = 0; i < n_ports; i++) {
 228                 usb_put_function(f_serial[i]);
 229                 usb_put_function_instance(fi_serial[i]);
 230         }
 231         return 0;
 232 }
 233
 234 static __refdata struct usb_composite_driver gserial_driver = {
 235         .name           = "g_serial",
 236         .dev            = &device_desc,
 237         .strings        = dev_strings,
 238         .max_speed      = USB_SPEED_SUPER,
 239         .bind           = gs_bind,
 240         .unbind         = gs_unbind,
 241 };
 242
 243 static int __init init(void)
 244 {
 245         /* We *could* export two configs; that'd be much cleaner...
 246          * but neither of these product IDs was defined that way.
 247          */
 248         if (use_acm) {
 249                 serial_config_driver.label = "CDC ACM config";
 250                 serial_config_driver.bConfigurationValue = 2;
 251                 device_desc.bDeviceClass = USB_CLASS_COMM;
 252                 device_desc.idProduct =
 253                                 cpu_to_le16(GS_CDC_PRODUCT_ID);
 254         } else if (use_obex) {
 255                 serial_config_driver.label = "CDC OBEX config";
 256                 serial_config_driver.bConfigurationValue = 3;
 257                 device_desc.bDeviceClass = USB_CLASS_COMM;
 258                 device_desc.idProduct =
 259                         cpu_to_le16(GS_CDC_OBEX_PRODUCT_ID);
 260         } else {
 261                 serial_config_driver.label = "Generic Serial config";
 262                 serial_config_driver.bConfigurationValue = 1;
 263                 device_desc.bDeviceClass = USB_CLASS_VENDOR_SPEC;
 264                 device_desc.idProduct =
 265                                 cpu_to_le16(GS_PRODUCT_ID);
 266         }
 267         strings_dev[STRING_DESCRIPTION_IDX].s = serial_config_driver.label;
 268
 269         return usb_composite_probe(&gserial_driver);
 270 }
 271 module_init(init);
 272
 273 static void __exit cleanup(void)
 274 {
 275         usb_composite_unregister(&gserial_driver);
 276 }
 277 module_exit(cleanup);