drivers/usb/gadget/legacy/zero.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * zero.c -- Gadget Zero, for USB development
   4  *
   5  * Copyright (C) 2003-2008 David Brownell
   6  * Copyright (C) 2008 by Nokia Corporation
   7  */
   8
   9 /*
  10  * Gadget Zero only needs two bulk endpoints, and is an example of how you
  11  * can write a hardware-agnostic gadget driver running inside a USB device.
  12  * Some hardware details are visible, but don't affect most of the driver.
  13  *
  14  * Use it with the Linux host/master side "usbtest" driver to get a basic
  15  * functional test of your device-side usb stack, or with "usb-skeleton".
  16  *
  17  * It supports two similar configurations.  One sinks whatever the usb host
  18  * writes, and in return sources zeroes.  The other loops whatever the host
  19  * writes back, so the host can read it.
  20  *
  21  * Many drivers will only have one configuration, letting them be much
  22  * simpler if they also don't support high speed operation (like this
  23  * driver does).
  24  *
  25  * Why is *this* driver using two configurations, rather than setting up
  26  * two interfaces with different functions?  To help verify that multiple
  27  * configuration infrastructure is working correctly; also, so that it can
  28  * work with low capability USB controllers without four bulk endpoints.
  29  */
  30
  31 /*
  32  * driver assumes self-powered hardware, and
  33  * has no way for users to trigger remote wakeup.
  34  */
  35
  36 /* #define VERBOSE_DEBUG */
  37
  38 #include <linux/kernel.h>
  39 #include <linux/slab.h>
  40 #include <linux/device.h>
  41 #include <linux/module.h>
  42 #include <linux/err.h>
  43 #include <linux/usb/composite.h>
  44
  45 #include "g_zero.h"
  46 /*-------------------------------------------------------------------------*/
  47 USB_GADGET_COMPOSITE_OPTIONS();
  48
  49 #define DRIVER_VERSION          "Cinco de Mayo 2008"
  50
  51 static const char longname[] = "Gadget Zero";
  52
  53 /*
  54  * Normally the "loopback" configuration is second (index 1) so
  55  * it's not the default.  Here's where to change that order, to
  56  * work better with hosts where config changes are problematic or
  57  * controllers (like original superh) that only support one config.
  58  */
  59 static bool loopdefault = 0;
  60 module_param(loopdefault, bool, S_IRUGO|S_IWUSR);
  61
  62 static struct usb_zero_options gzero_options = {
  63         .isoc_interval = GZERO_ISOC_INTERVAL,
  64         .isoc_maxpacket = GZERO_ISOC_MAXPACKET,
  65         .bulk_buflen = GZERO_BULK_BUFLEN,
  66         .qlen = GZERO_QLEN,
  67         .ss_bulk_qlen = GZERO_SS_BULK_QLEN,
  68         .ss_iso_qlen = GZERO_SS_ISO_QLEN,
  69 };
  70
  71 /*-------------------------------------------------------------------------*/
  72
  73 /* Thanks to NetChip Technologies for donating this product ID.
  74  *
  75  * DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
  76  * Instead:  allocate your own, using normal USB-IF procedures.
  77  */
  78 #ifndef CONFIG_USB_ZERO_HNPTEST
  79 #define DRIVER_VENDOR_NUM       0x0525          /* NetChip */
  80 #define DRIVER_PRODUCT_NUM      0xa4a0          /* Linux-USB "Gadget Zero" */
  81 #define DEFAULT_AUTORESUME      0
  82 #else
  83 #define DRIVER_VENDOR_NUM       0x1a0a          /* OTG test device IDs */
  84 #define DRIVER_PRODUCT_NUM      0xbadd
  85 #define DEFAULT_AUTORESUME      5
  86 #endif
  87
  88 /* If the optional "autoresume" mode is enabled, it provides good
  89  * functional coverage for the "USBCV" test harness from USB-IF.
  90  * It's always set if OTG mode is enabled.
  91  */
  92 static unsigned autoresume = DEFAULT_AUTORESUME;
  93 module_param(autoresume, uint, S_IRUGO);
  94 MODULE_PARM_DESC(autoresume, "zero, or seconds before remote wakeup");
  95
  96 /* Maximum Autoresume time */
  97 static unsigned max_autoresume;
  98 module_param(max_autoresume, uint, S_IRUGO);
  99 MODULE_PARM_DESC(max_autoresume, "maximum seconds before remote wakeup");
 100
 101 /* Interval between two remote wakeups */
 102 static unsigned autoresume_interval_ms;
 103 module_param(autoresume_interval_ms, uint, S_IRUGO);
 104 MODULE_PARM_DESC(autoresume_interval_ms,
 105                 "milliseconds to increase successive wakeup delays");
 106
 107 static unsigned autoresume_step_ms;
 108 /*-------------------------------------------------------------------------*/
 109
 110 static struct usb_device_descriptor device_desc = {
 111         .bLength =              sizeof device_desc,
 112         .bDescriptorType =      USB_DT_DEVICE,
 113
 114         /* .bcdUSB = DYNAMIC */
 115         .bDeviceClass =         USB_CLASS_VENDOR_SPEC,
 116
 117         .idVendor =             cpu_to_le16(DRIVER_VENDOR_NUM),
 118         .idProduct =            cpu_to_le16(DRIVER_PRODUCT_NUM),
 119         .bNumConfigurations =   2,
 120 };
 121
 122 static const struct usb_descriptor_header *otg_desc[2];
 123
 124 /* string IDs are assigned dynamically */
 125 /* default serial number takes at least two packets */
 126 static char serial[] = "0123456789.0123456789.0123456789";
 127
 128 #define USB_GZERO_SS_DESC       (USB_GADGET_FIRST_AVAIL_IDX + 0)
 129 #define USB_GZERO_LB_DESC       (USB_GADGET_FIRST_AVAIL_IDX + 1)
 130
 131 static struct usb_string strings_dev[] = {
 132         [USB_GADGET_MANUFACTURER_IDX].s = "",
 133         [USB_GADGET_PRODUCT_IDX].s = longname,
 134         [USB_GADGET_SERIAL_IDX].s = serial,
 135         [USB_GZERO_SS_DESC].s   = "source and sink data",
 136         [USB_GZERO_LB_DESC].s   = "loop input to output",
 137         {  }                    /* end of list */
 138 };
 139
 140 static struct usb_gadget_strings stringtab_dev = {
 141         .language       = 0x0409,       /* en-us */
 142         .strings        = strings_dev,
 143 };
 144
 145 static struct usb_gadget_strings *dev_strings[] = {
 146         &stringtab_dev,
 147         NULL,
 148 };
 149
 150 /*-------------------------------------------------------------------------*/
 151
 152 static struct timer_list        autoresume_timer;
 153 static struct usb_composite_dev *autoresume_cdev;
 154
 155 static void zero_autoresume(struct timer_list *unused)
 156 {
 157         struct usb_composite_dev        *cdev = autoresume_cdev;
 158         struct usb_gadget               *g = cdev->gadget;
 159
 160         /* unconfigured devices can't issue wakeups */
 161         if (!cdev->config)
 162                 return;
 163
 164         /* Normally the host would be woken up for something
 165          * more significant than just a timer firing; likely
 166          * because of some direct user request.
 167          */
 168         if (g->speed != USB_SPEED_UNKNOWN) {
 169                 int status = usb_gadget_wakeup(g);
 170                 INFO(cdev, "%s --> %d\n", __func__, status);
 171         }
 172 }
 173
 174 static void zero_suspend(struct usb_composite_dev *cdev)
 175 {
 176         if (cdev->gadget->speed == USB_SPEED_UNKNOWN)
 177                 return;
 178
 179         if (autoresume) {
 180                 if (max_autoresume &&
 181                         (autoresume_step_ms > max_autoresume * 1000))
 182                                 autoresume_step_ms = autoresume * 1000;
 183
 184                 mod_timer(&autoresume_timer, jiffies +
 185                         msecs_to_jiffies(autoresume_step_ms));
 186                 DBG(cdev, "suspend, wakeup in %d milliseconds\n",
 187                         autoresume_step_ms);
 188
 189                 autoresume_step_ms += autoresume_interval_ms;
 190         } else
 191                 DBG(cdev, "%s\n", __func__);
 192 }
 193
 194 static void zero_resume(struct usb_composite_dev *cdev)
 195 {
 196         DBG(cdev, "%s\n", __func__);
 197         del_timer(&autoresume_timer);
 198 }
 199
 200 /*-------------------------------------------------------------------------*/
 201
 202 static struct usb_configuration loopback_driver = {
 203         .label          = "loopback",
 204         .bConfigurationValue = 2,
 205         .bmAttributes   = USB_CONFIG_ATT_SELFPOWER,
 206         /* .iConfiguration = DYNAMIC */
 207 };
 208
 209 static struct usb_function *func_ss;
 210 static struct usb_function_instance *func_inst_ss;
 211
 212 static int ss_config_setup(struct usb_configuration *c,
 213                 const struct usb_ctrlrequest *ctrl)
 214 {
 215         switch (ctrl->bRequest) {
 216         case 0x5b:
 217         case 0x5c:
 218                 return func_ss->setup(func_ss, ctrl);
 219         default:
 220                 return -EOPNOTSUPP;
 221         }
 222 }
 223
 224 static struct usb_configuration sourcesink_driver = {
 225         .label                  = "source/sink",
 226         .setup                  = ss_config_setup,
 227         .bConfigurationValue    = 3,
 228         .bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
 229         /* .iConfiguration      = DYNAMIC */
 230 };
 231
 232 module_param_named(buflen, gzero_options.bulk_buflen, uint, 0);
 233 module_param_named(pattern, gzero_options.pattern, uint, S_IRUGO|S_IWUSR);
 234 MODULE_PARM_DESC(pattern, "0 = all zeroes, 1 = mod63, 2 = none");
 235
 236 module_param_named(isoc_interval, gzero_options.isoc_interval, uint,
 237                 S_IRUGO|S_IWUSR);
 238 MODULE_PARM_DESC(isoc_interval, "1 - 16");
 239
 240 module_param_named(isoc_maxpacket, gzero_options.isoc_maxpacket, uint,
 241                 S_IRUGO|S_IWUSR);
 242 MODULE_PARM_DESC(isoc_maxpacket, "0 - 1023 (fs), 0 - 1024 (hs/ss)");
 243
 244 module_param_named(isoc_mult, gzero_options.isoc_mult, uint, S_IRUGO|S_IWUSR);
 245 MODULE_PARM_DESC(isoc_mult, "0 - 2 (hs/ss only)");
 246
 247 module_param_named(isoc_maxburst, gzero_options.isoc_maxburst, uint,
 248                 S_IRUGO|S_IWUSR);
 249 MODULE_PARM_DESC(isoc_maxburst, "0 - 15 (ss only)");
 250
 251 static struct usb_function *func_lb;
 252 static struct usb_function_instance *func_inst_lb;
 253
 254 module_param_named(qlen, gzero_options.qlen, uint, S_IRUGO|S_IWUSR);
 255 MODULE_PARM_DESC(qlen, "depth of loopback queue");
 256
 257 module_param_named(ss_bulk_qlen, gzero_options.ss_bulk_qlen, uint,
 258                 S_IRUGO|S_IWUSR);
 259 MODULE_PARM_DESC(bulk_qlen, "depth of sourcesink queue for bulk transfer");
 260
 261 module_param_named(ss_iso_qlen, gzero_options.ss_iso_qlen, uint,
 262                 S_IRUGO|S_IWUSR);
 263 MODULE_PARM_DESC(iso_qlen, "depth of sourcesink queue for iso transfer");
 264
 265 static int zero_bind(struct usb_composite_dev *cdev)
 266 {
 267         struct f_ss_opts        *ss_opts;
 268         struct f_lb_opts        *lb_opts;
 269         int                     status;
 270
 271         /* Allocate string descriptor numbers ... note that string
 272          * contents can be overridden by the composite_dev glue.
 273          */
 274         status = usb_string_ids_tab(cdev, strings_dev);
 275         if (status < 0)
 276                 return status;
 277
 278         device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
 279         device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
 280         device_desc.iSerialNumber = strings_dev[USB_GADGET_SERIAL_IDX].id;
 281
 282         autoresume_cdev = cdev;
 283         timer_setup(&autoresume_timer, zero_autoresume, 0);
 284
 285         func_inst_ss = usb_get_function_instance("SourceSink");
 286         if (IS_ERR(func_inst_ss))
 287                 return PTR_ERR(func_inst_ss);
 288
 289         ss_opts =  container_of(func_inst_ss, struct f_ss_opts, func_inst);
 290         ss_opts->pattern = gzero_options.pattern;
 291         ss_opts->isoc_interval = gzero_options.isoc_interval;
 292         ss_opts->isoc_maxpacket = gzero_options.isoc_maxpacket;
 293         ss_opts->isoc_mult = gzero_options.isoc_mult;
 294         ss_opts->isoc_maxburst = gzero_options.isoc_maxburst;
 295         ss_opts->bulk_buflen = gzero_options.bulk_buflen;
 296         ss_opts->bulk_qlen = gzero_options.ss_bulk_qlen;
 297         ss_opts->iso_qlen = gzero_options.ss_iso_qlen;
 298
 299         func_ss = usb_get_function(func_inst_ss);
 300         if (IS_ERR(func_ss)) {
 301                 status = PTR_ERR(func_ss);
 302                 goto err_put_func_inst_ss;
 303         }
 304
 305         func_inst_lb = usb_get_function_instance("Loopback");
 306         if (IS_ERR(func_inst_lb)) {
 307                 status = PTR_ERR(func_inst_lb);
 308                 goto err_put_func_ss;
 309         }
 310
 311         lb_opts = container_of(func_inst_lb, struct f_lb_opts, func_inst);
 312         lb_opts->bulk_buflen = gzero_options.bulk_buflen;
 313         lb_opts->qlen = gzero_options.qlen;
 314
 315         func_lb = usb_get_function(func_inst_lb);
 316         if (IS_ERR(func_lb)) {
 317                 status = PTR_ERR(func_lb);
 318                 goto err_put_func_inst_lb;
 319         }
 320
 321         sourcesink_driver.iConfiguration = strings_dev[USB_GZERO_SS_DESC].id;
 322         loopback_driver.iConfiguration = strings_dev[USB_GZERO_LB_DESC].id;
 323
 324         /* support autoresume for remote wakeup testing */
 325         sourcesink_driver.bmAttributes &= ~USB_CONFIG_ATT_WAKEUP;
 326         loopback_driver.bmAttributes &= ~USB_CONFIG_ATT_WAKEUP;
 327         sourcesink_driver.descriptors = NULL;
 328         loopback_driver.descriptors = NULL;
 329         if (autoresume) {
 330                 sourcesink_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 331                 loopback_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 332                 autoresume_step_ms = autoresume * 1000;
 333         }
 334
 335         /* support OTG systems */
 336         if (gadget_is_otg(cdev->gadget)) {
 337                 if (!otg_desc[0]) {
 338                         struct usb_descriptor_header *usb_desc;
 339
 340                         usb_desc = usb_otg_descriptor_alloc(cdev->gadget);
 341                         if (!usb_desc) {
 342                                 status = -ENOMEM;
 343                                 goto err_conf_flb;
 344                         }
 345                         usb_otg_descriptor_init(cdev->gadget, usb_desc);
 346                         otg_desc[0] = usb_desc;
 347                         otg_desc[1] = NULL;
 348                 }
 349                 sourcesink_driver.descriptors = otg_desc;
 350                 sourcesink_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 351                 loopback_driver.descriptors = otg_desc;
 352                 loopback_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 353         }
 354
 355         /* Register primary, then secondary configuration.  Note that
 356          * SH3 only allows one config...
 357          */
 358         if (loopdefault) {
 359                 usb_add_config_only(cdev, &loopback_driver);
 360                 usb_add_config_only(cdev, &sourcesink_driver);
 361         } else {
 362                 usb_add_config_only(cdev, &sourcesink_driver);
 363                 usb_add_config_only(cdev, &loopback_driver);
 364         }
 365         status = usb_add_function(&sourcesink_driver, func_ss);
 366         if (status)
 367                 goto err_free_otg_desc;
 368
 369         usb_ep_autoconfig_reset(cdev->gadget);
 370         status = usb_add_function(&loopback_driver, func_lb);
 371         if (status)
 372                 goto err_free_otg_desc;
 373
 374         usb_ep_autoconfig_reset(cdev->gadget);
 375         usb_composite_overwrite_options(cdev, &coverwrite);
 376
 377         INFO(cdev, "%s, version: " DRIVER_VERSION "\n", longname);
 378
 379         return 0;
 380
 381 err_free_otg_desc:
 382         kfree(otg_desc[0]);
 383         otg_desc[0] = NULL;
 384 err_conf_flb:
 385         usb_put_function(func_lb);
 386         func_lb = NULL;
 387 err_put_func_inst_lb:
 388         usb_put_function_instance(func_inst_lb);
 389         func_inst_lb = NULL;
 390 err_put_func_ss:
 391         usb_put_function(func_ss);
 392         func_ss = NULL;
 393 err_put_func_inst_ss:
 394         usb_put_function_instance(func_inst_ss);
 395         func_inst_ss = NULL;
 396         return status;
 397 }
 398
 399 static int zero_unbind(struct usb_composite_dev *cdev)
 400 {
 401         del_timer_sync(&autoresume_timer);
 402         if (!IS_ERR_OR_NULL(func_ss))
 403                 usb_put_function(func_ss);
 404         usb_put_function_instance(func_inst_ss);
 405         if (!IS_ERR_OR_NULL(func_lb))
 406                 usb_put_function(func_lb);
 407         usb_put_function_instance(func_inst_lb);
 408         kfree(otg_desc[0]);
 409         otg_desc[0] = NULL;
 410
 411         return 0;
 412 }
 413
 414 static struct usb_composite_driver zero_driver = {
 415         .name           = "zero",
 416         .dev            = &device_desc,
 417         .strings        = dev_strings,
 418         .max_speed      = USB_SPEED_SUPER,
 419         .bind           = zero_bind,
 420         .unbind         = zero_unbind,
 421         .suspend        = zero_suspend,
 422         .resume         = zero_resume,
 423 };
 424
 425 module_usb_composite_driver(zero_driver);
 426
 427 MODULE_AUTHOR("David Brownell");
 428 MODULE_LICENSE("GPL");