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 const struct usb_descriptor_header *otg_desc[2];
  83
  84 /*-------------------------------------------------------------------------*/
  85
  86 /* Module */
  87 MODULE_DESCRIPTION(GS_VERSION_NAME);
  88 MODULE_AUTHOR("Al Borchers");
  89 MODULE_AUTHOR("David Brownell");
  90 MODULE_LICENSE("GPL");
  91
  92 static bool use_acm = true;
  93 module_param(use_acm, bool, 0);
  94 MODULE_PARM_DESC(use_acm, "Use CDC ACM, default=yes");
  95
  96 static bool use_obex = false;
  97 module_param(use_obex, bool, 0);
  98 MODULE_PARM_DESC(use_obex, "Use CDC OBEX, default=no");
  99
 100 static unsigned n_ports = 1;
 101 module_param(n_ports, uint, 0);
 102 MODULE_PARM_DESC(n_ports, "number of ports to create, default=1");
 103
 104 /*-------------------------------------------------------------------------*/
 105
 106 static struct usb_configuration serial_config_driver = {
 107         /* .label = f(use_acm) */
 108         /* .bConfigurationValue = f(use_acm) */
 109         /* .iConfiguration = DYNAMIC */
 110         .bmAttributes   = USB_CONFIG_ATT_SELFPOWER,
 111 };
 112
 113 static struct usb_function_instance *fi_serial[MAX_U_SERIAL_PORTS];
 114 static struct usb_function *f_serial[MAX_U_SERIAL_PORTS];
 115
 116 static int serial_register_ports(struct usb_composite_dev *cdev,
 117                 struct usb_configuration *c, const char *f_name)
 118 {
 119         int i;
 120         int ret;
 121
 122         ret = usb_add_config_only(cdev, c);
 123         if (ret)
 124                 goto out;
 125
 126         for (i = 0; i < n_ports; i++) {
 127
 128                 fi_serial[i] = usb_get_function_instance(f_name);
 129                 if (IS_ERR(fi_serial[i])) {
 130                         ret = PTR_ERR(fi_serial[i]);
 131                         goto fail;
 132                 }
 133
 134                 f_serial[i] = usb_get_function(fi_serial[i]);
 135                 if (IS_ERR(f_serial[i])) {
 136                         ret = PTR_ERR(f_serial[i]);
 137                         goto err_get_func;
 138                 }
 139
 140                 ret = usb_add_function(c, f_serial[i]);
 141                 if (ret)
 142                         goto err_add_func;
 143         }
 144
 145         return 0;
 146
 147 err_add_func:
 148         usb_put_function(f_serial[i]);
 149 err_get_func:
 150         usb_put_function_instance(fi_serial[i]);
 151
 152 fail:
 153         i--;
 154         while (i >= 0) {
 155                 usb_remove_function(c, f_serial[i]);
 156                 usb_put_function(f_serial[i]);
 157                 usb_put_function_instance(fi_serial[i]);
 158                 i--;
 159         }
 160 out:
 161         return ret;
 162 }
 163
 164 static int gs_bind(struct usb_composite_dev *cdev)
 165 {
 166         int                     status;
 167
 168         /* Allocate string descriptor numbers ... note that string
 169          * contents can be overridden by the composite_dev glue.
 170          */
 171
 172         status = usb_string_ids_tab(cdev, strings_dev);
 173         if (status < 0)
 174                 goto fail;
 175         device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
 176         device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
 177         status = strings_dev[STRING_DESCRIPTION_IDX].id;
 178         serial_config_driver.iConfiguration = status;
 179
 180         if (gadget_is_otg(cdev->gadget)) {
 181                 if (!otg_desc[0]) {
 182                         struct usb_descriptor_header *usb_desc;
 183
 184                         usb_desc = usb_otg_descriptor_alloc(cdev->gadget);
 185                         if (!usb_desc) {
 186                                 status = -ENOMEM;
 187                                 goto fail;
 188                         }
 189                         usb_otg_descriptor_init(cdev->gadget, usb_desc);
 190                         otg_desc[0] = usb_desc;
 191                         otg_desc[1] = NULL;
 192                 }
 193                 serial_config_driver.descriptors = otg_desc;
 194                 serial_config_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 195         }
 196
 197         /* register our configuration */
 198         if (use_acm) {
 199                 status  = serial_register_ports(cdev, &serial_config_driver,
 200                                 "acm");
 201                 usb_ep_autoconfig_reset(cdev->gadget);
 202         } else if (use_obex)
 203                 status = serial_register_ports(cdev, &serial_config_driver,
 204                                 "obex");
 205         else {
 206                 status = serial_register_ports(cdev, &serial_config_driver,
 207                                 "gser");
 208         }
 209         if (status < 0)
 210                 goto fail1;
 211
 212         usb_composite_overwrite_options(cdev, &coverwrite);
 213         INFO(cdev, "%s\n", GS_VERSION_NAME);
 214
 215         return 0;
 216 fail1:
 217         kfree(otg_desc[0]);
 218         otg_desc[0] = NULL;
 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
 232         kfree(otg_desc[0]);
 233         otg_desc[0] = NULL;
 234
 235         return 0;
 236 }
 237
 238 static struct usb_composite_driver gserial_driver = {
 239         .name           = "g_serial",
 240         .dev            = &device_desc,
 241         .strings        = dev_strings,
 242         .max_speed      = USB_SPEED_SUPER,
 243         .bind           = gs_bind,
 244         .unbind         = gs_unbind,
 245 };
 246
 247 static int __init init(void)
 248 {
 249         /* We *could* export two configs; that'd be much cleaner...
 250          * but neither of these product IDs was defined that way.
 251          */
 252         if (use_acm) {
 253                 serial_config_driver.label = "CDC ACM config";
 254                 serial_config_driver.bConfigurationValue = 2;
 255                 device_desc.bDeviceClass = USB_CLASS_COMM;
 256                 device_desc.idProduct =
 257                                 cpu_to_le16(GS_CDC_PRODUCT_ID);
 258         } else if (use_obex) {
 259                 serial_config_driver.label = "CDC OBEX config";
 260                 serial_config_driver.bConfigurationValue = 3;
 261                 device_desc.bDeviceClass = USB_CLASS_COMM;
 262                 device_desc.idProduct =
 263                         cpu_to_le16(GS_CDC_OBEX_PRODUCT_ID);
 264         } else {
 265                 serial_config_driver.label = "Generic Serial config";
 266                 serial_config_driver.bConfigurationValue = 1;
 267                 device_desc.bDeviceClass = USB_CLASS_VENDOR_SPEC;
 268                 device_desc.idProduct =
 269                                 cpu_to_le16(GS_PRODUCT_ID);
 270         }
 271         strings_dev[STRING_DESCRIPTION_IDX].s = serial_config_driver.label;
 272
 273         return usb_composite_probe(&gserial_driver);
 274 }
 275 module_init(init);
 276
 277 static void __exit cleanup(void)
 278 {
 279         usb_composite_unregister(&gserial_driver);
 280 }
 281 module_exit(cleanup);