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