drivers/usb/gadget/serial.c

   1 /*
   2  * g_serial.c -- USB gadget serial driver
   3  *
   4  * Copyright 2003 (C) Al Borchers (alborchers@steinerpoint.com)
   5  *
   6  * This code is based in part on the Gadget Zero driver, which
   7  * is Copyright (C) 2003 by David Brownell, all rights reserved.
   8  *
   9  * This code also borrows from usbserial.c, which is
  10  * Copyright (C) 1999 - 2002 Greg Kroah-Hartman (greg@kroah.com)
  11  * Copyright (C) 2000 Peter Berger (pberger@brimson.com)
  12  * Copyright (C) 2000 Al Borchers (alborchers@steinerpoint.com)
  13  *
  14  * This software is distributed under the terms of the GNU General
  15  * Public License ("GPL") as published by the Free Software Foundation,
  16  * either version 2 of that License or (at your option) any later version.
  17  *
  18  */
  19
  20 #include <linux/kernel.h>
  21 #include <linux/utsname.h>
  22 #include <linux/device.h>
  23 #include <linux/tty.h>
  24 #include <linux/tty_flip.h>
  25
  26 #include <linux/usb/ch9.h>
  27 #include <linux/usb/cdc.h>
  28 #include <linux/usb/gadget.h>
  29
  30 #include "gadget_chips.h"
  31
  32
  33 /* Defines */
  34
  35 #define GS_VERSION_STR                  "v2.2"
  36 #define GS_VERSION_NUM                  0x0202
  37
  38 #define GS_LONG_NAME                    "Gadget Serial"
  39 #define GS_SHORT_NAME                   "g_serial"
  40
  41 #define GS_MAJOR                        127
  42 #define GS_MINOR_START                  0
  43
  44 #define GS_NUM_PORTS                    16
  45
  46 #define GS_NUM_CONFIGS                  1
  47 #define GS_NO_CONFIG_ID                 0
  48 #define GS_BULK_CONFIG_ID               1
  49 #define GS_ACM_CONFIG_ID                2
  50
  51 #define GS_MAX_NUM_INTERFACES           2
  52 #define GS_BULK_INTERFACE_ID            0
  53 #define GS_CONTROL_INTERFACE_ID         0
  54 #define GS_DATA_INTERFACE_ID            1
  55
  56 #define GS_MAX_DESC_LEN                 256
  57
  58 #define GS_DEFAULT_READ_Q_SIZE          32
  59 #define GS_DEFAULT_WRITE_Q_SIZE         32
  60
  61 #define GS_DEFAULT_WRITE_BUF_SIZE       8192
  62 #define GS_TMP_BUF_SIZE                 8192
  63
  64 #define GS_CLOSE_TIMEOUT                15
  65
  66 #define GS_DEFAULT_USE_ACM              0
  67
  68 #define GS_DEFAULT_DTE_RATE             9600
  69 #define GS_DEFAULT_DATA_BITS            8
  70 #define GS_DEFAULT_PARITY               USB_CDC_NO_PARITY
  71 #define GS_DEFAULT_CHAR_FORMAT          USB_CDC_1_STOP_BITS
  72
  73 /* maxpacket and other transfer characteristics vary by speed. */
  74 static inline struct usb_endpoint_descriptor *
  75 choose_ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *hs,
  76                 struct usb_endpoint_descriptor *fs)
  77 {
  78         if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
  79                 return hs;
  80         return fs;
  81 }
  82
  83
  84 /* debug settings */
  85 #ifdef DEBUG
  86 static int debug = 1;
  87 #else
  88 #define debug 0
  89 #endif
  90
  91 #define gs_debug(format, arg...) \
  92         do { if (debug) pr_debug(format, ## arg); } while (0)
  93 #define gs_debug_level(level, format, arg...) \
  94         do { if (debug >= level) pr_debug(format, ## arg); } while (0)
  95
  96
  97 /* Thanks to NetChip Technologies for donating this product ID.
  98  *
  99  * DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
 100  * Instead:  allocate your own, using normal USB-IF procedures.
 101  */
 102 #define GS_VENDOR_ID                    0x0525  /* NetChip */
 103 #define GS_PRODUCT_ID                   0xa4a6  /* Linux-USB Serial Gadget */
 104 #define GS_CDC_PRODUCT_ID               0xa4a7  /* ... as CDC-ACM */
 105
 106 #define GS_LOG2_NOTIFY_INTERVAL         5       /* 1 << 5 == 32 msec */
 107 #define GS_NOTIFY_MAXPACKET             8
 108
 109
 110 /* Structures */
 111
 112 struct gs_dev;
 113
 114 /* circular buffer */
 115 struct gs_buf {
 116         unsigned int            buf_size;
 117         char                    *buf_buf;
 118         char                    *buf_get;
 119         char                    *buf_put;
 120 };
 121
 122 /* list of requests */
 123 struct gs_req_entry {
 124         struct list_head        re_entry;
 125         struct usb_request      *re_req;
 126 };
 127
 128 /* the port structure holds info for each port, one for each minor number */
 129 struct gs_port {
 130         struct gs_dev           *port_dev;      /* pointer to device struct */
 131         struct tty_struct       *port_tty;      /* pointer to tty struct */
 132         spinlock_t              port_lock;
 133         int                     port_num;
 134         int                     port_open_count;
 135         int                     port_in_use;    /* open/close in progress */
 136         wait_queue_head_t       port_write_wait;/* waiting to write */
 137         struct gs_buf           *port_write_buf;
 138         struct usb_cdc_line_coding port_line_coding;    /* 8-N-1 etc */
 139         u16                     port_handshake_bits;
 140 #define RS232_RTS       (1 << 1)
 141 #define RS232_DTE       (1 << 0)
 142 };
 143
 144 /* the device structure holds info for the USB device */
 145 struct gs_dev {
 146         struct usb_gadget       *dev_gadget;    /* gadget device pointer */
 147         spinlock_t              dev_lock;       /* lock for set/reset config */
 148         int                     dev_config;     /* configuration number */
 149         struct usb_ep           *dev_notify_ep; /* address of notify endpoint */
 150         struct usb_ep           *dev_in_ep;     /* address of in endpoint */
 151         struct usb_ep           *dev_out_ep;    /* address of out endpoint */
 152         struct usb_endpoint_descriptor          /* descriptor of notify ep */
 153                                 *dev_notify_ep_desc;
 154         struct usb_endpoint_descriptor          /* descriptor of in endpoint */
 155                                 *dev_in_ep_desc;
 156         struct usb_endpoint_descriptor          /* descriptor of out endpoint */
 157                                 *dev_out_ep_desc;
 158         struct usb_request      *dev_ctrl_req;  /* control request */
 159         struct list_head        dev_req_list;   /* list of write requests */
 160         int                     dev_sched_port; /* round robin port scheduled */
 161         struct gs_port          *dev_port[GS_NUM_PORTS]; /* the ports */
 162 };
 163
 164
 165 /* Functions */
 166
 167 /* module */
 168 static int __init gs_module_init(void);
 169 static void __exit gs_module_exit(void);
 170
 171 /* tty driver */
 172 static int gs_open(struct tty_struct *tty, struct file *file);
 173 static void gs_close(struct tty_struct *tty, struct file *file);
 174 static int gs_write(struct tty_struct *tty,
 175         const unsigned char *buf, int count);
 176 static int gs_put_char(struct tty_struct *tty, unsigned char ch);
 177 static void gs_flush_chars(struct tty_struct *tty);
 178 static int gs_write_room(struct tty_struct *tty);
 179 static int gs_chars_in_buffer(struct tty_struct *tty);
 180 static void gs_throttle(struct tty_struct * tty);
 181 static void gs_unthrottle(struct tty_struct * tty);
 182 static void gs_break(struct tty_struct *tty, int break_state);
 183 static int  gs_ioctl(struct tty_struct *tty, struct file *file,
 184         unsigned int cmd, unsigned long arg);
 185 static void gs_set_termios(struct tty_struct *tty, struct ktermios *old);
 186
 187 static int gs_send(struct gs_dev *dev);
 188 static int gs_send_packet(struct gs_dev *dev, char *packet,
 189         unsigned int size);
 190 static int gs_recv_packet(struct gs_dev *dev, char *packet,
 191         unsigned int size);
 192 static void gs_read_complete(struct usb_ep *ep, struct usb_request *req);
 193 static void gs_write_complete(struct usb_ep *ep, struct usb_request *req);
 194
 195 /* gadget driver */
 196 static int gs_bind(struct usb_gadget *gadget);
 197 static void gs_unbind(struct usb_gadget *gadget);
 198 static int gs_setup(struct usb_gadget *gadget,
 199         const struct usb_ctrlrequest *ctrl);
 200 static int gs_setup_standard(struct usb_gadget *gadget,
 201         const struct usb_ctrlrequest *ctrl);
 202 static int gs_setup_class(struct usb_gadget *gadget,
 203         const struct usb_ctrlrequest *ctrl);
 204 static void gs_setup_complete(struct usb_ep *ep, struct usb_request *req);
 205 static void gs_setup_complete_set_line_coding(struct usb_ep *ep,
 206         struct usb_request *req);
 207 static void gs_disconnect(struct usb_gadget *gadget);
 208 static int gs_set_config(struct gs_dev *dev, unsigned config);
 209 static void gs_reset_config(struct gs_dev *dev);
 210 static int gs_build_config_buf(u8 *buf, struct usb_gadget *g,
 211                 u8 type, unsigned int index, int is_otg);
 212
 213 static struct usb_request *gs_alloc_req(struct usb_ep *ep, unsigned int len,
 214         gfp_t kmalloc_flags);
 215 static void gs_free_req(struct usb_ep *ep, struct usb_request *req);
 216
 217 static struct gs_req_entry *gs_alloc_req_entry(struct usb_ep *ep, unsigned len,
 218         gfp_t kmalloc_flags);
 219 static void gs_free_req_entry(struct usb_ep *ep, struct gs_req_entry *req);
 220
 221 static int gs_alloc_ports(struct gs_dev *dev, gfp_t kmalloc_flags);
 222 static void gs_free_ports(struct gs_dev *dev);
 223
 224 /* circular buffer */
 225 static struct gs_buf *gs_buf_alloc(unsigned int size, gfp_t kmalloc_flags);
 226 static void gs_buf_free(struct gs_buf *gb);
 227 static void gs_buf_clear(struct gs_buf *gb);
 228 static unsigned int gs_buf_data_avail(struct gs_buf *gb);
 229 static unsigned int gs_buf_space_avail(struct gs_buf *gb);
 230 static unsigned int gs_buf_put(struct gs_buf *gb, const char *buf,
 231         unsigned int count);
 232 static unsigned int gs_buf_get(struct gs_buf *gb, char *buf,
 233         unsigned int count);
 234
 235 /* external functions */
 236 extern int net2280_set_fifo_mode(struct usb_gadget *gadget, int mode);
 237
 238
 239 /* Globals */
 240
 241 static struct gs_dev *gs_device;
 242
 243 static const char *EP_IN_NAME;
 244 static const char *EP_OUT_NAME;
 245 static const char *EP_NOTIFY_NAME;
 246
 247 static struct mutex gs_open_close_lock[GS_NUM_PORTS];
 248
 249 static unsigned int read_q_size = GS_DEFAULT_READ_Q_SIZE;
 250 static unsigned int write_q_size = GS_DEFAULT_WRITE_Q_SIZE;
 251
 252 static unsigned int write_buf_size = GS_DEFAULT_WRITE_BUF_SIZE;
 253
 254 static unsigned int use_acm = GS_DEFAULT_USE_ACM;
 255
 256
 257 /* tty driver struct */
 258 static const struct tty_operations gs_tty_ops = {
 259         .open =                 gs_open,
 260         .close =                gs_close,
 261         .write =                gs_write,
 262         .put_char =             gs_put_char,
 263         .flush_chars =          gs_flush_chars,
 264         .write_room =           gs_write_room,
 265         .ioctl =                gs_ioctl,
 266         .set_termios =          gs_set_termios,
 267         .throttle =             gs_throttle,
 268         .unthrottle =           gs_unthrottle,
 269         .break_ctl =            gs_break,
 270         .chars_in_buffer =      gs_chars_in_buffer,
 271 };
 272 static struct tty_driver *gs_tty_driver;
 273
 274 /* gadget driver struct */
 275 static struct usb_gadget_driver gs_gadget_driver = {
 276 #ifdef CONFIG_USB_GADGET_DUALSPEED
 277         .speed =                USB_SPEED_HIGH,
 278 #else
 279         .speed =                USB_SPEED_FULL,
 280 #endif /* CONFIG_USB_GADGET_DUALSPEED */
 281         .function =             GS_LONG_NAME,
 282         .bind =                 gs_bind,
 283         .unbind =               gs_unbind,
 284         .setup =                gs_setup,
 285         .disconnect =           gs_disconnect,
 286         .driver = {
 287                 .name =         GS_SHORT_NAME,
 288         },
 289 };
 290
 291
 292 /* USB descriptors */
 293
 294 #define GS_MANUFACTURER_STR_ID  1
 295 #define GS_PRODUCT_STR_ID       2
 296 #define GS_SERIAL_STR_ID        3
 297 #define GS_BULK_CONFIG_STR_ID   4
 298 #define GS_ACM_CONFIG_STR_ID    5
 299 #define GS_CONTROL_STR_ID       6
 300 #define GS_DATA_STR_ID          7
 301
 302 /* static strings, in UTF-8 */
 303 static char manufacturer[50];
 304 static struct usb_string gs_strings[] = {
 305         { GS_MANUFACTURER_STR_ID, manufacturer },
 306         { GS_PRODUCT_STR_ID, GS_LONG_NAME },
 307         { GS_SERIAL_STR_ID, "0" },
 308         { GS_BULK_CONFIG_STR_ID, "Gadget Serial Bulk" },
 309         { GS_ACM_CONFIG_STR_ID, "Gadget Serial CDC ACM" },
 310         { GS_CONTROL_STR_ID, "Gadget Serial Control" },
 311         { GS_DATA_STR_ID, "Gadget Serial Data" },
 312         {  } /* end of list */
 313 };
 314
 315 static struct usb_gadget_strings gs_string_table = {
 316         .language =             0x0409, /* en-us */
 317         .strings =              gs_strings,
 318 };
 319
 320 static struct usb_device_descriptor gs_device_desc = {
 321         .bLength =              USB_DT_DEVICE_SIZE,
 322         .bDescriptorType =      USB_DT_DEVICE,
 323         .bcdUSB =               __constant_cpu_to_le16(0x0200),
 324         .bDeviceSubClass =      0,
 325         .bDeviceProtocol =      0,
 326         .idVendor =             __constant_cpu_to_le16(GS_VENDOR_ID),
 327         .idProduct =            __constant_cpu_to_le16(GS_PRODUCT_ID),
 328         .iManufacturer =        GS_MANUFACTURER_STR_ID,
 329         .iProduct =             GS_PRODUCT_STR_ID,
 330         .iSerialNumber =        GS_SERIAL_STR_ID,
 331         .bNumConfigurations =   GS_NUM_CONFIGS,
 332 };
 333
 334 static struct usb_otg_descriptor gs_otg_descriptor = {
 335         .bLength =              sizeof(gs_otg_descriptor),
 336         .bDescriptorType =      USB_DT_OTG,
 337         .bmAttributes =         USB_OTG_SRP,
 338 };
 339
 340 static struct usb_config_descriptor gs_bulk_config_desc = {
 341         .bLength =              USB_DT_CONFIG_SIZE,
 342         .bDescriptorType =      USB_DT_CONFIG,
 343         /* .wTotalLength computed dynamically */
 344         .bNumInterfaces =       1,
 345         .bConfigurationValue =  GS_BULK_CONFIG_ID,
 346         .iConfiguration =       GS_BULK_CONFIG_STR_ID,
 347         .bmAttributes =         USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
 348         .bMaxPower =            1,
 349 };
 350
 351 static struct usb_config_descriptor gs_acm_config_desc = {
 352         .bLength =              USB_DT_CONFIG_SIZE,
 353         .bDescriptorType =      USB_DT_CONFIG,
 354         /* .wTotalLength computed dynamically */
 355         .bNumInterfaces =       2,
 356         .bConfigurationValue =  GS_ACM_CONFIG_ID,
 357         .iConfiguration =       GS_ACM_CONFIG_STR_ID,
 358         .bmAttributes =         USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
 359         .bMaxPower =            1,
 360 };
 361
 362 static const struct usb_interface_descriptor gs_bulk_interface_desc = {
 363         .bLength =              USB_DT_INTERFACE_SIZE,
 364         .bDescriptorType =      USB_DT_INTERFACE,
 365         .bInterfaceNumber =     GS_BULK_INTERFACE_ID,
 366         .bNumEndpoints =        2,
 367         .bInterfaceClass =      USB_CLASS_CDC_DATA,
 368         .bInterfaceSubClass =   0,
 369         .bInterfaceProtocol =   0,
 370         .iInterface =           GS_DATA_STR_ID,
 371 };
 372
 373 static const struct usb_interface_descriptor gs_control_interface_desc = {
 374         .bLength =              USB_DT_INTERFACE_SIZE,
 375         .bDescriptorType =      USB_DT_INTERFACE,
 376         .bInterfaceNumber =     GS_CONTROL_INTERFACE_ID,
 377         .bNumEndpoints =        1,
 378         .bInterfaceClass =      USB_CLASS_COMM,
 379         .bInterfaceSubClass =   USB_CDC_SUBCLASS_ACM,
 380         .bInterfaceProtocol =   USB_CDC_ACM_PROTO_AT_V25TER,
 381         .iInterface =           GS_CONTROL_STR_ID,
 382 };
 383
 384 static const struct usb_interface_descriptor gs_data_interface_desc = {
 385         .bLength =              USB_DT_INTERFACE_SIZE,
 386         .bDescriptorType =      USB_DT_INTERFACE,
 387         .bInterfaceNumber =     GS_DATA_INTERFACE_ID,
 388         .bNumEndpoints =        2,
 389         .bInterfaceClass =      USB_CLASS_CDC_DATA,
 390         .bInterfaceSubClass =   0,
 391         .bInterfaceProtocol =   0,
 392         .iInterface =           GS_DATA_STR_ID,
 393 };
 394
 395 static const struct usb_cdc_header_desc gs_header_desc = {
 396         .bLength =              sizeof(gs_header_desc),
 397         .bDescriptorType =      USB_DT_CS_INTERFACE,
 398         .bDescriptorSubType =   USB_CDC_HEADER_TYPE,
 399         .bcdCDC =               __constant_cpu_to_le16(0x0110),
 400 };
 401
 402 static const struct usb_cdc_call_mgmt_descriptor gs_call_mgmt_descriptor = {
 403         .bLength =              sizeof(gs_call_mgmt_descriptor),
 404         .bDescriptorType =      USB_DT_CS_INTERFACE,
 405         .bDescriptorSubType =   USB_CDC_CALL_MANAGEMENT_TYPE,
 406         .bmCapabilities =       0,
 407         .bDataInterface =       1,      /* index of data interface */
 408 };
 409
 410 static struct usb_cdc_acm_descriptor gs_acm_descriptor = {
 411         .bLength =              sizeof(gs_acm_descriptor),
 412         .bDescriptorType =      USB_DT_CS_INTERFACE,
 413         .bDescriptorSubType =   USB_CDC_ACM_TYPE,
 414         .bmCapabilities =       (1 << 1),
 415 };
 416
 417 static const struct usb_cdc_union_desc gs_union_desc = {
 418         .bLength =              sizeof(gs_union_desc),
 419         .bDescriptorType =      USB_DT_CS_INTERFACE,
 420         .bDescriptorSubType =   USB_CDC_UNION_TYPE,
 421         .bMasterInterface0 =    0,      /* index of control interface */
 422         .bSlaveInterface0 =     1,      /* index of data interface */
 423 };
 424
 425 static struct usb_endpoint_descriptor gs_fullspeed_notify_desc = {
 426         .bLength =              USB_DT_ENDPOINT_SIZE,
 427         .bDescriptorType =      USB_DT_ENDPOINT,
 428         .bEndpointAddress =     USB_DIR_IN,
 429         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 430         .wMaxPacketSize =       __constant_cpu_to_le16(GS_NOTIFY_MAXPACKET),
 431         .bInterval =            1 << GS_LOG2_NOTIFY_INTERVAL,
 432 };
 433
 434 static struct usb_endpoint_descriptor gs_fullspeed_in_desc = {
 435         .bLength =              USB_DT_ENDPOINT_SIZE,
 436         .bDescriptorType =      USB_DT_ENDPOINT,
 437         .bEndpointAddress =     USB_DIR_IN,
 438         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 439 };
 440
 441 static struct usb_endpoint_descriptor gs_fullspeed_out_desc = {
 442         .bLength =              USB_DT_ENDPOINT_SIZE,
 443         .bDescriptorType =      USB_DT_ENDPOINT,
 444         .bEndpointAddress =     USB_DIR_OUT,
 445         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 446 };
 447
 448 static const struct usb_descriptor_header *gs_bulk_fullspeed_function[] = {
 449         (struct usb_descriptor_header *) &gs_otg_descriptor,
 450         (struct usb_descriptor_header *) &gs_bulk_interface_desc,
 451         (struct usb_descriptor_header *) &gs_fullspeed_in_desc,
 452         (struct usb_descriptor_header *) &gs_fullspeed_out_desc,
 453         NULL,
 454 };
 455
 456 static const struct usb_descriptor_header *gs_acm_fullspeed_function[] = {
 457         (struct usb_descriptor_header *) &gs_otg_descriptor,
 458         (struct usb_descriptor_header *) &gs_control_interface_desc,
 459         (struct usb_descriptor_header *) &gs_header_desc,
 460         (struct usb_descriptor_header *) &gs_call_mgmt_descriptor,
 461         (struct usb_descriptor_header *) &gs_acm_descriptor,
 462         (struct usb_descriptor_header *) &gs_union_desc,
 463         (struct usb_descriptor_header *) &gs_fullspeed_notify_desc,
 464         (struct usb_descriptor_header *) &gs_data_interface_desc,
 465         (struct usb_descriptor_header *) &gs_fullspeed_in_desc,
 466         (struct usb_descriptor_header *) &gs_fullspeed_out_desc,
 467         NULL,
 468 };
 469
 470 static struct usb_endpoint_descriptor gs_highspeed_notify_desc = {
 471         .bLength =              USB_DT_ENDPOINT_SIZE,
 472         .bDescriptorType =      USB_DT_ENDPOINT,
 473         .bEndpointAddress =     USB_DIR_IN,
 474         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 475         .wMaxPacketSize =       __constant_cpu_to_le16(GS_NOTIFY_MAXPACKET),
 476         .bInterval =            GS_LOG2_NOTIFY_INTERVAL+4,
 477 };
 478
 479 static struct usb_endpoint_descriptor gs_highspeed_in_desc = {
 480         .bLength =              USB_DT_ENDPOINT_SIZE,
 481         .bDescriptorType =      USB_DT_ENDPOINT,
 482         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 483         .wMaxPacketSize =       __constant_cpu_to_le16(512),
 484 };
 485
 486 static struct usb_endpoint_descriptor gs_highspeed_out_desc = {
 487         .bLength =              USB_DT_ENDPOINT_SIZE,
 488         .bDescriptorType =      USB_DT_ENDPOINT,
 489         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 490         .wMaxPacketSize =       __constant_cpu_to_le16(512),
 491 };
 492
 493 static struct usb_qualifier_descriptor gs_qualifier_desc = {
 494         .bLength =              sizeof(struct usb_qualifier_descriptor),
 495         .bDescriptorType =      USB_DT_DEVICE_QUALIFIER,
 496         .bcdUSB =               __constant_cpu_to_le16 (0x0200),
 497         /* assumes ep0 uses the same value for both speeds ... */
 498         .bNumConfigurations =   GS_NUM_CONFIGS,
 499 };
 500
 501 static const struct usb_descriptor_header *gs_bulk_highspeed_function[] = {
 502         (struct usb_descriptor_header *) &gs_otg_descriptor,
 503         (struct usb_descriptor_header *) &gs_bulk_interface_desc,
 504         (struct usb_descriptor_header *) &gs_highspeed_in_desc,
 505         (struct usb_descriptor_header *) &gs_highspeed_out_desc,
 506         NULL,
 507 };
 508
 509 static const struct usb_descriptor_header *gs_acm_highspeed_function[] = {
 510         (struct usb_descriptor_header *) &gs_otg_descriptor,
 511         (struct usb_descriptor_header *) &gs_control_interface_desc,
 512         (struct usb_descriptor_header *) &gs_header_desc,
 513         (struct usb_descriptor_header *) &gs_call_mgmt_descriptor,
 514         (struct usb_descriptor_header *) &gs_acm_descriptor,
 515         (struct usb_descriptor_header *) &gs_union_desc,
 516         (struct usb_descriptor_header *) &gs_highspeed_notify_desc,
 517         (struct usb_descriptor_header *) &gs_data_interface_desc,
 518         (struct usb_descriptor_header *) &gs_highspeed_in_desc,
 519         (struct usb_descriptor_header *) &gs_highspeed_out_desc,
 520         NULL,
 521 };
 522
 523
 524 /* Module */
 525 MODULE_DESCRIPTION(GS_LONG_NAME);
 526 MODULE_AUTHOR("Al Borchers");
 527 MODULE_LICENSE("GPL");
 528
 529 #ifdef DEBUG
 530 module_param(debug, int, S_IRUGO|S_IWUSR);
 531 MODULE_PARM_DESC(debug, "Enable debugging, 0=off, 1=on");
 532 #endif
 533
 534 module_param(read_q_size, uint, S_IRUGO);
 535 MODULE_PARM_DESC(read_q_size, "Read request queue size, default=32");
 536
 537 module_param(write_q_size, uint, S_IRUGO);
 538 MODULE_PARM_DESC(write_q_size, "Write request queue size, default=32");
 539
 540 module_param(write_buf_size, uint, S_IRUGO);
 541 MODULE_PARM_DESC(write_buf_size, "Write buffer size, default=8192");
 542
 543 module_param(use_acm, uint, S_IRUGO);
 544 MODULE_PARM_DESC(use_acm, "Use CDC ACM, 0=no, 1=yes, default=no");
 545
 546 module_init(gs_module_init);
 547 module_exit(gs_module_exit);
 548
 549 /*
 550 *  gs_module_init
 551 *
 552 *  Register as a USB gadget driver and a tty driver.
 553 */
 554 static int __init gs_module_init(void)
 555 {
 556         int i;
 557         int retval;
 558
 559         retval = usb_gadget_register_driver(&gs_gadget_driver);
 560         if (retval) {
 561                 pr_err("gs_module_init: cannot register gadget driver, "
 562                         "ret=%d\n", retval);
 563                 return retval;
 564         }
 565
 566         gs_tty_driver = alloc_tty_driver(GS_NUM_PORTS);
 567         if (!gs_tty_driver)
 568                 return -ENOMEM;
 569         gs_tty_driver->owner = THIS_MODULE;
 570         gs_tty_driver->driver_name = GS_SHORT_NAME;
 571         gs_tty_driver->name = "ttygs";
 572         gs_tty_driver->major = GS_MAJOR;
 573         gs_tty_driver->minor_start = GS_MINOR_START;
 574         gs_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
 575         gs_tty_driver->subtype = SERIAL_TYPE_NORMAL;
 576         gs_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
 577         gs_tty_driver->init_termios = tty_std_termios;
 578         gs_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
 579         tty_set_operations(gs_tty_driver, &gs_tty_ops);
 580
 581         for (i=0; i < GS_NUM_PORTS; i++)
 582                 mutex_init(&gs_open_close_lock[i]);
 583
 584         retval = tty_register_driver(gs_tty_driver);
 585         if (retval) {
 586                 usb_gadget_unregister_driver(&gs_gadget_driver);
 587                 put_tty_driver(gs_tty_driver);
 588                 pr_err("gs_module_init: cannot register tty driver, "
 589                                 "ret=%d\n", retval);
 590                 return retval;
 591         }
 592
 593         pr_info("gs_module_init: %s %s loaded\n",
 594                         GS_LONG_NAME, GS_VERSION_STR);
 595         return 0;
 596 }
 597
 598 /*
 599 * gs_module_exit
 600 *
 601 * Unregister as a tty driver and a USB gadget driver.
 602 */
 603 static void __exit gs_module_exit(void)
 604 {
 605         tty_unregister_driver(gs_tty_driver);
 606         put_tty_driver(gs_tty_driver);
 607         usb_gadget_unregister_driver(&gs_gadget_driver);
 608
 609         pr_info("gs_module_exit: %s %s unloaded\n",
 610                         GS_LONG_NAME, GS_VERSION_STR);
 611 }
 612
 613 /* TTY Driver */
 614
 615 /*
 616  * gs_open
 617  */
 618 static int gs_open(struct tty_struct *tty, struct file *file)
 619 {
 620         int port_num;
 621         unsigned long flags;
 622         struct gs_port *port;
 623         struct gs_dev *dev;
 624         struct gs_buf *buf;
 625         struct mutex *mtx;
 626         int ret;
 627
 628         port_num = tty->index;
 629
 630         gs_debug("gs_open: (%d,%p,%p)\n", port_num, tty, file);
 631
 632         if (port_num < 0 || port_num >= GS_NUM_PORTS) {
 633                 pr_err("gs_open: (%d,%p,%p) invalid port number\n",
 634                         port_num, tty, file);
 635                 return -ENODEV;
 636         }
 637
 638         dev = gs_device;
 639
 640         if (dev == NULL) {
 641                 pr_err("gs_open: (%d,%p,%p) NULL device pointer\n",
 642                         port_num, tty, file);
 643                 return -ENODEV;
 644         }
 645
 646         mtx = &gs_open_close_lock[port_num];
 647         if (mutex_lock_interruptible(mtx)) {
 648                 pr_err("gs_open: (%d,%p,%p) interrupted waiting for mutex\n",
 649                         port_num, tty, file);
 650                 return -ERESTARTSYS;
 651         }
 652
 653         spin_lock_irqsave(&dev->dev_lock, flags);
 654
 655         if (dev->dev_config == GS_NO_CONFIG_ID) {
 656                 pr_err("gs_open: (%d,%p,%p) device is not connected\n",
 657                         port_num, tty, file);
 658                 ret = -ENODEV;
 659                 goto exit_unlock_dev;
 660         }
 661
 662         port = dev->dev_port[port_num];
 663
 664         if (port == NULL) {
 665                 pr_err("gs_open: (%d,%p,%p) NULL port pointer\n",
 666                         port_num, tty, file);
 667                 ret = -ENODEV;
 668                 goto exit_unlock_dev;
 669         }
 670
 671         spin_lock(&port->port_lock);
 672         spin_unlock(&dev->dev_lock);
 673
 674         if (port->port_dev == NULL) {
 675                 pr_err("gs_open: (%d,%p,%p) port disconnected (1)\n",
 676                         port_num, tty, file);
 677                 ret = -EIO;
 678                 goto exit_unlock_port;
 679         }
 680
 681         if (port->port_open_count > 0) {
 682                 ++port->port_open_count;
 683                 gs_debug("gs_open: (%d,%p,%p) already open\n",
 684                         port_num, tty, file);
 685                 ret = 0;
 686                 goto exit_unlock_port;
 687         }
 688
 689         tty->driver_data = NULL;
 690
 691         /* mark port as in use, we can drop port lock and sleep if necessary */
 692         port->port_in_use = 1;
 693
 694         /* allocate write buffer on first open */
 695         if (port->port_write_buf == NULL) {
 696                 spin_unlock_irqrestore(&port->port_lock, flags);
 697                 buf = gs_buf_alloc(write_buf_size, GFP_KERNEL);
 698                 spin_lock_irqsave(&port->port_lock, flags);
 699
 700                 /* might have been disconnected while asleep, check */
 701                 if (port->port_dev == NULL) {
 702                         pr_err("gs_open: (%d,%p,%p) port disconnected (2)\n",
 703                                 port_num, tty, file);
 704                         port->port_in_use = 0;
 705                         ret = -EIO;
 706                         goto exit_unlock_port;
 707                 }
 708
 709                 if ((port->port_write_buf=buf) == NULL) {
 710                         pr_err("gs_open: (%d,%p,%p) cannot allocate "
 711                                 "port write buffer\n",
 712                                 port_num, tty, file);
 713                         port->port_in_use = 0;
 714                         ret = -ENOMEM;
 715                         goto exit_unlock_port;
 716                 }
 717
 718         }
 719
 720         /* wait for carrier detect (not implemented) */
 721
 722         /* might have been disconnected while asleep, check */
 723         if (port->port_dev == NULL) {
 724                 pr_err("gs_open: (%d,%p,%p) port disconnected (3)\n",
 725                         port_num, tty, file);
 726                 port->port_in_use = 0;
 727                 ret = -EIO;
 728                 goto exit_unlock_port;
 729         }
 730
 731         tty->driver_data = port;
 732         port->port_tty = tty;
 733         port->port_open_count = 1;
 734         port->port_in_use = 0;
 735
 736         gs_debug("gs_open: (%d,%p,%p) completed\n", port_num, tty, file);
 737
 738         ret = 0;
 739
 740 exit_unlock_port:
 741         spin_unlock_irqrestore(&port->port_lock, flags);
 742         mutex_unlock(mtx);
 743         return ret;
 744
 745 exit_unlock_dev:
 746         spin_unlock_irqrestore(&dev->dev_lock, flags);
 747         mutex_unlock(mtx);
 748         return ret;
 749
 750 }
 751
 752 /*
 753  * gs_close
 754  */
 755
 756 #define GS_WRITE_FINISHED_EVENT_SAFELY(p)                       \
 757 ({                                                              \
 758         int cond;                                               \
 759                                                                 \
 760         spin_lock_irq(&(p)->port_lock);                         \
 761         cond = !(p)->port_dev || !gs_buf_data_avail((p)->port_write_buf); \
 762         spin_unlock_irq(&(p)->port_lock);                       \
 763         cond;                                                   \
 764 })
 765
 766 static void gs_close(struct tty_struct *tty, struct file *file)
 767 {
 768         struct gs_port *port = tty->driver_data;
 769         struct mutex *mtx;
 770
 771         if (port == NULL) {
 772                 pr_err("gs_close: NULL port pointer\n");
 773                 return;
 774         }
 775
 776         gs_debug("gs_close: (%d,%p,%p)\n", port->port_num, tty, file);
 777
 778         mtx = &gs_open_close_lock[port->port_num];
 779         mutex_lock(mtx);
 780
 781         spin_lock_irq(&port->port_lock);
 782
 783         if (port->port_open_count == 0) {
 784                 pr_err("gs_close: (%d,%p,%p) port is already closed\n",
 785                         port->port_num, tty, file);
 786                 goto exit;
 787         }
 788
 789         if (port->port_open_count > 1) {
 790                 --port->port_open_count;
 791                 goto exit;
 792         }
 793
 794         /* free disconnected port on final close */
 795         if (port->port_dev == NULL) {
 796                 kfree(port);
 797                 goto exit;
 798         }
 799
 800         /* mark port as closed but in use, we can drop port lock */
 801         /* and sleep if necessary */
 802         port->port_in_use = 1;
 803         port->port_open_count = 0;
 804
 805         /* wait for write buffer to drain, or */
 806         /* at most GS_CLOSE_TIMEOUT seconds */
 807         if (gs_buf_data_avail(port->port_write_buf) > 0) {
 808                 spin_unlock_irq(&port->port_lock);
 809                 wait_event_interruptible_timeout(port->port_write_wait,
 810                                         GS_WRITE_FINISHED_EVENT_SAFELY(port),
 811                                         GS_CLOSE_TIMEOUT * HZ);
 812                 spin_lock_irq(&port->port_lock);
 813         }
 814
 815         /* free disconnected port on final close */
 816         /* (might have happened during the above sleep) */
 817         if (port->port_dev == NULL) {
 818                 kfree(port);
 819                 goto exit;
 820         }
 821
 822         gs_buf_clear(port->port_write_buf);
 823
 824         tty->driver_data = NULL;
 825         port->port_tty = NULL;
 826         port->port_in_use = 0;
 827
 828         gs_debug("gs_close: (%d,%p,%p) completed\n",
 829                 port->port_num, tty, file);
 830
 831 exit:
 832         spin_unlock_irq(&port->port_lock);
 833         mutex_unlock(mtx);
 834 }
 835
 836 /*
 837  * gs_write
 838  */
 839 static int gs_write(struct tty_struct *tty, const unsigned char *buf, int count)
 840 {
 841         unsigned long flags;
 842         struct gs_port *port = tty->driver_data;
 843         int ret;
 844
 845         if (port == NULL) {
 846                 pr_err("gs_write: NULL port pointer\n");
 847                 return -EIO;
 848         }
 849
 850         gs_debug("gs_write: (%d,%p) writing %d bytes\n", port->port_num, tty,
 851                 count);
 852
 853         if (count == 0)
 854                 return 0;
 855
 856         spin_lock_irqsave(&port->port_lock, flags);
 857
 858         if (port->port_dev == NULL) {
 859                 pr_err("gs_write: (%d,%p) port is not connected\n",
 860                         port->port_num, tty);
 861                 ret = -EIO;
 862                 goto exit;
 863         }
 864
 865         if (port->port_open_count == 0) {
 866                 pr_err("gs_write: (%d,%p) port is closed\n",
 867                         port->port_num, tty);
 868                 ret = -EBADF;
 869                 goto exit;
 870         }
 871
 872         count = gs_buf_put(port->port_write_buf, buf, count);
 873
 874         spin_unlock_irqrestore(&port->port_lock, flags);
 875
 876         gs_send(gs_device);
 877
 878         gs_debug("gs_write: (%d,%p) wrote %d bytes\n", port->port_num, tty,
 879                 count);
 880
 881         return count;
 882
 883 exit:
 884         spin_unlock_irqrestore(&port->port_lock, flags);
 885         return ret;
 886 }
 887
 888 /*
 889  * gs_put_char
 890  */
 891 static int gs_put_char(struct tty_struct *tty, unsigned char ch)
 892 {
 893         unsigned long flags;
 894         struct gs_port *port = tty->driver_data;
 895         int ret = 0;
 896
 897         if (port == NULL) {
 898                 pr_err("gs_put_char: NULL port pointer\n");
 899                 return 0;
 900         }
 901
 902         gs_debug("gs_put_char: (%d,%p) char=0x%x, called from %p\n",
 903                 port->port_num, tty, ch, __builtin_return_address(0));
 904
 905         spin_lock_irqsave(&port->port_lock, flags);
 906
 907         if (port->port_dev == NULL) {
 908                 pr_err("gs_put_char: (%d,%p) port is not connected\n",
 909                         port->port_num, tty);
 910                 goto exit;
 911         }
 912
 913         if (port->port_open_count == 0) {
 914                 pr_err("gs_put_char: (%d,%p) port is closed\n",
 915                         port->port_num, tty);
 916                 goto exit;
 917         }
 918
 919         ret = gs_buf_put(port->port_write_buf, &ch, 1);
 920
 921 exit:
 922         spin_unlock_irqrestore(&port->port_lock, flags);
 923         return ret;
 924 }
 925
 926 /*
 927  * gs_flush_chars
 928  */
 929 static void gs_flush_chars(struct tty_struct *tty)
 930 {
 931         unsigned long flags;
 932         struct gs_port *port = tty->driver_data;
 933
 934         if (port == NULL) {
 935                 pr_err("gs_flush_chars: NULL port pointer\n");
 936                 return;
 937         }
 938
 939         gs_debug("gs_flush_chars: (%d,%p)\n", port->port_num, tty);
 940
 941         spin_lock_irqsave(&port->port_lock, flags);
 942
 943         if (port->port_dev == NULL) {
 944                 pr_err("gs_flush_chars: (%d,%p) port is not connected\n",
 945                         port->port_num, tty);
 946                 goto exit;
 947         }
 948
 949         if (port->port_open_count == 0) {
 950                 pr_err("gs_flush_chars: (%d,%p) port is closed\n",
 951                         port->port_num, tty);
 952                 goto exit;
 953         }
 954
 955         spin_unlock_irqrestore(&port->port_lock, flags);
 956
 957         gs_send(gs_device);
 958
 959         return;
 960
 961 exit:
 962         spin_unlock_irqrestore(&port->port_lock, flags);
 963 }
 964
 965 /*
 966  * gs_write_room
 967  */
 968 static int gs_write_room(struct tty_struct *tty)
 969 {
 970
 971         int room = 0;
 972         unsigned long flags;
 973         struct gs_port *port = tty->driver_data;
 974
 975
 976         if (port == NULL)
 977                 return 0;
 978
 979         spin_lock_irqsave(&port->port_lock, flags);
 980
 981         if (port->port_dev != NULL && port->port_open_count > 0
 982         && port->port_write_buf != NULL)
 983                 room = gs_buf_space_avail(port->port_write_buf);
 984
 985         spin_unlock_irqrestore(&port->port_lock, flags);
 986
 987         gs_debug("gs_write_room: (%d,%p) room=%d\n",
 988                 port->port_num, tty, room);
 989
 990         return room;
 991 }
 992
 993 /*
 994  * gs_chars_in_buffer
 995  */
 996 static int gs_chars_in_buffer(struct tty_struct *tty)
 997 {
 998         int chars = 0;
 999         unsigned long flags;
1000         struct gs_port *port = tty->driver_data;
1001
1002         if (port == NULL)
1003                 return 0;
1004
1005         spin_lock_irqsave(&port->port_lock, flags);
1006
1007         if (port->port_dev != NULL && port->port_open_count > 0
1008         && port->port_write_buf != NULL)
1009                 chars = gs_buf_data_avail(port->port_write_buf);
1010
1011         spin_unlock_irqrestore(&port->port_lock, flags);
1012
1013         gs_debug("gs_chars_in_buffer: (%d,%p) chars=%d\n",
1014                 port->port_num, tty, chars);
1015
1016         return chars;
1017 }
1018
1019 /*
1020  * gs_throttle
1021  */
1022 static void gs_throttle(struct tty_struct *tty)
1023 {
1024 }
1025
1026 /*
1027  * gs_unthrottle
1028  */
1029 static void gs_unthrottle(struct tty_struct *tty)
1030 {
1031 }
1032
1033 /*
1034  * gs_break
1035  */
1036 static void gs_break(struct tty_struct *tty, int break_state)
1037 {
1038 }
1039
1040 /*
1041  * gs_ioctl
1042  */
1043 static int gs_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg)
1044 {
1045         struct gs_port *port = tty->driver_data;
1046
1047         if (port == NULL) {
1048                 pr_err("gs_ioctl: NULL port pointer\n");
1049                 return -EIO;
1050         }
1051
1052         gs_debug("gs_ioctl: (%d,%p,%p) cmd=0x%4.4x, arg=%lu\n",
1053                 port->port_num, tty, file, cmd, arg);
1054
1055         /* handle ioctls */
1056
1057         /* could not handle ioctl */
1058         return -ENOIOCTLCMD;
1059 }
1060
1061 /*
1062  * gs_set_termios
1063  */
1064 static void gs_set_termios(struct tty_struct *tty, struct ktermios *old)
1065 {
1066 }
1067
1068 /*
1069 * gs_send
1070 *
1071 * This function finds available write requests, calls
1072 * gs_send_packet to fill these packets with data, and
1073 * continues until either there are no more write requests
1074 * available or no more data to send.  This function is
1075 * run whenever data arrives or write requests are available.
1076 */
1077 static int gs_send(struct gs_dev *dev)
1078 {
1079         int ret,len;
1080         unsigned long flags;
1081         struct usb_ep *ep;
1082         struct usb_request *req;
1083         struct gs_req_entry *req_entry;
1084
1085         if (dev == NULL) {
1086                 pr_err("gs_send: NULL device pointer\n");
1087                 return -ENODEV;
1088         }
1089
1090         spin_lock_irqsave(&dev->dev_lock, flags);
1091
1092         ep = dev->dev_in_ep;
1093
1094         while(!list_empty(&dev->dev_req_list)) {
1095
1096                 req_entry = list_entry(dev->dev_req_list.next,
1097                         struct gs_req_entry, re_entry);
1098
1099                 req = req_entry->re_req;
1100
1101                 len = gs_send_packet(dev, req->buf, ep->maxpacket);
1102
1103                 if (len > 0) {
1104                         gs_debug_level(3, "gs_send: len=%d, 0x%2.2x "
1105                                         "0x%2.2x 0x%2.2x ...\n", len,
1106                                         *((unsigned char *)req->buf),
1107                                         *((unsigned char *)req->buf+1),
1108                                         *((unsigned char *)req->buf+2));
1109                         list_del(&req_entry->re_entry);
1110                         req->length = len;
1111                         spin_unlock_irqrestore(&dev->dev_lock, flags);
1112                         if ((ret=usb_ep_queue(ep, req, GFP_ATOMIC))) {
1113                                 pr_err(
1114                                 "gs_send: cannot queue read request, ret=%d\n",
1115                                         ret);
1116                                 spin_lock_irqsave(&dev->dev_lock, flags);
1117                                 break;
1118                         }
1119                         spin_lock_irqsave(&dev->dev_lock, flags);
1120                 } else {
1121                         break;
1122                 }
1123
1124         }
1125
1126         spin_unlock_irqrestore(&dev->dev_lock, flags);
1127
1128         return 0;
1129 }
1130
1131 /*
1132  * gs_send_packet
1133  *
1134  * If there is data to send, a packet is built in the given
1135  * buffer and the size is returned.  If there is no data to
1136  * send, 0 is returned.  If there is any error a negative
1137  * error number is returned.
1138  *
1139  * Called during USB completion routine, on interrupt time.
1140  *
1141  * We assume that disconnect will not happen until all completion
1142  * routines have completed, so we can assume that the dev_port
1143  * array does not change during the lifetime of this function.
1144  */
1145 static int gs_send_packet(struct gs_dev *dev, char *packet, unsigned int size)
1146 {
1147         unsigned int len;
1148         struct gs_port *port;
1149
1150         /* TEMPORARY -- only port 0 is supported right now */
1151         port = dev->dev_port[0];
1152
1153         if (port == NULL) {
1154                 pr_err("gs_send_packet: port=%d, NULL port pointer\n", 0);
1155                 return -EIO;
1156         }
1157
1158         spin_lock(&port->port_lock);
1159
1160         len = gs_buf_data_avail(port->port_write_buf);
1161         if (len < size)
1162                 size = len;
1163
1164         if (size == 0)
1165                 goto exit;
1166
1167         size = gs_buf_get(port->port_write_buf, packet, size);
1168
1169         if (port->port_tty)
1170                 wake_up_interruptible(&port->port_tty->write_wait);
1171
1172 exit:
1173         spin_unlock(&port->port_lock);
1174         return size;
1175 }
1176
1177 /*
1178  * gs_recv_packet
1179  *
1180  * Called for each USB packet received.  Reads the packet
1181  * header and stuffs the data in the appropriate tty buffer.
1182  * Returns 0 if successful, or a negative error number.
1183  *
1184  * Called during USB completion routine, on interrupt time.
1185  *
1186  * We assume that disconnect will not happen until all completion
1187  * routines have completed, so we can assume that the dev_port
1188  * array does not change during the lifetime of this function.
1189  */
1190 static int gs_recv_packet(struct gs_dev *dev, char *packet, unsigned int size)
1191 {
1192         unsigned int len;
1193         struct gs_port *port;
1194         int ret;
1195         struct tty_struct *tty;
1196
1197         /* TEMPORARY -- only port 0 is supported right now */
1198         port = dev->dev_port[0];
1199
1200         if (port == NULL) {
1201                 pr_err("gs_recv_packet: port=%d, NULL port pointer\n",
1202                         port->port_num);
1203                 return -EIO;
1204         }
1205
1206         spin_lock(&port->port_lock);
1207
1208         if (port->port_open_count == 0) {
1209                 pr_err("gs_recv_packet: port=%d, port is closed\n",
1210                         port->port_num);
1211                 ret = -EIO;
1212                 goto exit;
1213         }
1214
1215
1216         tty = port->port_tty;
1217
1218         if (tty == NULL) {
1219                 pr_err("gs_recv_packet: port=%d, NULL tty pointer\n",
1220                         port->port_num);
1221                 ret = -EIO;
1222                 goto exit;
1223         }
1224
1225         if (port->port_tty->magic != TTY_MAGIC) {
1226                 pr_err("gs_recv_packet: port=%d, bad tty magic\n",
1227                         port->port_num);
1228                 ret = -EIO;
1229                 goto exit;
1230         }
1231
1232         len = tty_buffer_request_room(tty, size);
1233         if (len > 0) {
1234                 tty_insert_flip_string(tty, packet, len);
1235                 tty_flip_buffer_push(port->port_tty);
1236                 wake_up_interruptible(&port->port_tty->read_wait);
1237         }
1238         ret = 0;
1239 exit:
1240         spin_unlock(&port->port_lock);
1241         return ret;
1242 }
1243
1244 /*
1245 * gs_read_complete
1246 */
1247 static void gs_read_complete(struct usb_ep *ep, struct usb_request *req)
1248 {
1249         int ret;
1250         struct gs_dev *dev = ep->driver_data;
1251
1252         if (dev == NULL) {
1253                 pr_err("gs_read_complete: NULL device pointer\n");
1254                 return;
1255         }
1256
1257         switch(req->status) {
1258         case 0:
1259                 /* normal completion */
1260                 gs_recv_packet(dev, req->buf, req->actual);
1261 requeue:
1262                 req->length = ep->maxpacket;
1263                 if ((ret=usb_ep_queue(ep, req, GFP_ATOMIC))) {
1264                         pr_err(
1265                         "gs_read_complete: cannot queue read request, ret=%d\n",
1266                                 ret);
1267                 }
1268                 break;
1269
1270         case -ESHUTDOWN:
1271                 /* disconnect */
1272                 gs_debug("gs_read_complete: shutdown\n");
1273                 gs_free_req(ep, req);
1274                 break;
1275
1276         default:
1277                 /* unexpected */
1278                 pr_err(
1279                 "gs_read_complete: unexpected status error, status=%d\n",
1280                         req->status);
1281                 goto requeue;
1282                 break;
1283         }
1284 }
1285
1286 /*
1287 * gs_write_complete
1288 */
1289 static void gs_write_complete(struct usb_ep *ep, struct usb_request *req)
1290 {
1291         struct gs_dev *dev = ep->driver_data;
1292         struct gs_req_entry *gs_req = req->context;
1293
1294         if (dev == NULL) {
1295                 pr_err("gs_write_complete: NULL device pointer\n");
1296                 return;
1297         }
1298
1299         switch(req->status) {
1300         case 0:
1301                 /* normal completion */
1302 requeue:
1303                 if (gs_req == NULL) {
1304                         pr_err("gs_write_complete: NULL request pointer\n");
1305                         return;
1306                 }
1307
1308                 spin_lock(&dev->dev_lock);
1309                 list_add(&gs_req->re_entry, &dev->dev_req_list);
1310                 spin_unlock(&dev->dev_lock);
1311
1312                 gs_send(dev);
1313
1314                 break;
1315
1316         case -ESHUTDOWN:
1317                 /* disconnect */
1318                 gs_debug("gs_write_complete: shutdown\n");
1319                 gs_free_req(ep, req);
1320                 break;
1321
1322         default:
1323                 pr_err(
1324                 "gs_write_complete: unexpected status error, status=%d\n",
1325                         req->status);
1326                 goto requeue;
1327                 break;
1328         }
1329 }
1330
1331 /* Gadget Driver */
1332
1333 /*
1334  * gs_bind
1335  *
1336  * Called on module load.  Allocates and initializes the device
1337  * structure and a control request.
1338  */
1339 static int __init gs_bind(struct usb_gadget *gadget)
1340 {
1341         int ret;
1342         struct usb_ep *ep;
1343         struct gs_dev *dev;
1344         int gcnum;
1345
1346         /* Some controllers can't support CDC ACM:
1347          * - sh doesn't support multiple interfaces or configs;
1348          * - sa1100 doesn't have a third interrupt endpoint
1349          */
1350         if (gadget_is_sh(gadget) || gadget_is_sa1100(gadget))
1351                 use_acm = 0;
1352
1353         gcnum = usb_gadget_controller_number(gadget);
1354         if (gcnum >= 0)
1355                 gs_device_desc.bcdDevice =
1356                                 cpu_to_le16(GS_VERSION_NUM | gcnum);
1357         else {
1358                 pr_warning("gs_bind: controller '%s' not recognized\n",
1359                         gadget->name);
1360                 /* unrecognized, but safe unless bulk is REALLY quirky */
1361                 gs_device_desc.bcdDevice =
1362                         __constant_cpu_to_le16(GS_VERSION_NUM|0x0099);
1363         }
1364
1365         usb_ep_autoconfig_reset(gadget);
1366
1367         ep = usb_ep_autoconfig(gadget, &gs_fullspeed_in_desc);
1368         if (!ep)
1369                 goto autoconf_fail;
1370         EP_IN_NAME = ep->name;
1371         ep->driver_data = ep;   /* claim the endpoint */
1372
1373         ep = usb_ep_autoconfig(gadget, &gs_fullspeed_out_desc);
1374         if (!ep)
1375                 goto autoconf_fail;
1376         EP_OUT_NAME = ep->name;
1377         ep->driver_data = ep;   /* claim the endpoint */
1378
1379         if (use_acm) {
1380                 ep = usb_ep_autoconfig(gadget, &gs_fullspeed_notify_desc);
1381                 if (!ep) {
1382                         pr_err("gs_bind: cannot run ACM on %s\n", gadget->name);
1383                         goto autoconf_fail;
1384                 }
1385                 gs_device_desc.idProduct = __constant_cpu_to_le16(
1386                                                 GS_CDC_PRODUCT_ID),
1387                 EP_NOTIFY_NAME = ep->name;
1388                 ep->driver_data = ep;   /* claim the endpoint */
1389         }
1390
1391         gs_device_desc.bDeviceClass = use_acm
1392                 ? USB_CLASS_COMM : USB_CLASS_VENDOR_SPEC;
1393         gs_device_desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
1394
1395         if (gadget_is_dualspeed(gadget)) {
1396                 gs_qualifier_desc.bDeviceClass = use_acm
1397                         ? USB_CLASS_COMM : USB_CLASS_VENDOR_SPEC;
1398                 /* assume ep0 uses the same packet size for both speeds */
1399                 gs_qualifier_desc.bMaxPacketSize0 =
1400                         gs_device_desc.bMaxPacketSize0;
1401                 /* assume endpoints are dual-speed */
1402                 gs_highspeed_notify_desc.bEndpointAddress =
1403                         gs_fullspeed_notify_desc.bEndpointAddress;
1404                 gs_highspeed_in_desc.bEndpointAddress =
1405                         gs_fullspeed_in_desc.bEndpointAddress;
1406                 gs_highspeed_out_desc.bEndpointAddress =
1407                         gs_fullspeed_out_desc.bEndpointAddress;
1408         }
1409
1410         usb_gadget_set_selfpowered(gadget);
1411
1412         if (gadget_is_otg(gadget)) {
1413                 gs_otg_descriptor.bmAttributes |= USB_OTG_HNP,
1414                 gs_bulk_config_desc.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
1415                 gs_acm_config_desc.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
1416         }
1417
1418         gs_device = dev = kzalloc(sizeof(struct gs_dev), GFP_KERNEL);
1419         if (dev == NULL)
1420                 return -ENOMEM;
1421
1422         snprintf(manufacturer, sizeof(manufacturer), "%s %s with %s",
1423                 init_utsname()->sysname, init_utsname()->release,
1424                 gadget->name);
1425
1426         dev->dev_gadget = gadget;
1427         spin_lock_init(&dev->dev_lock);
1428         INIT_LIST_HEAD(&dev->dev_req_list);
1429         set_gadget_data(gadget, dev);
1430
1431         if ((ret=gs_alloc_ports(dev, GFP_KERNEL)) != 0) {
1432                 pr_err("gs_bind: cannot allocate ports\n");
1433                 gs_unbind(gadget);
1434                 return ret;
1435         }
1436
1437         /* preallocate control response and buffer */
1438         dev->dev_ctrl_req = gs_alloc_req(gadget->ep0, GS_MAX_DESC_LEN,
1439                 GFP_KERNEL);
1440         if (dev->dev_ctrl_req == NULL) {
1441                 gs_unbind(gadget);
1442                 return -ENOMEM;
1443         }
1444         dev->dev_ctrl_req->complete = gs_setup_complete;
1445
1446         gadget->ep0->driver_data = dev;
1447
1448         pr_info("gs_bind: %s %s bound\n",
1449                 GS_LONG_NAME, GS_VERSION_STR);
1450
1451         return 0;
1452
1453 autoconf_fail:
1454         pr_err("gs_bind: cannot autoconfigure on %s\n", gadget->name);
1455         return -ENODEV;
1456 }
1457
1458 /*
1459  * gs_unbind
1460  *
1461  * Called on module unload.  Frees the control request and device
1462  * structure.
1463  */
1464 static void /* __init_or_exit */ gs_unbind(struct usb_gadget *gadget)
1465 {
1466         struct gs_dev *dev = get_gadget_data(gadget);
1467
1468         gs_device = NULL;
1469
1470         /* read/write requests already freed, only control request remains */
1471         if (dev != NULL) {
1472                 if (dev->dev_ctrl_req != NULL) {
1473                         gs_free_req(gadget->ep0, dev->dev_ctrl_req);
1474                         dev->dev_ctrl_req = NULL;
1475                 }
1476                 gs_free_ports(dev);
1477                 if (dev->dev_notify_ep)
1478                         usb_ep_disable(dev->dev_notify_ep);
1479                 if (dev->dev_in_ep)
1480                         usb_ep_disable(dev->dev_in_ep);
1481                 if (dev->dev_out_ep)
1482                         usb_ep_disable(dev->dev_out_ep);
1483                 kfree(dev);
1484                 set_gadget_data(gadget, NULL);
1485         }
1486
1487         pr_info("gs_unbind: %s %s unbound\n", GS_LONG_NAME,
1488                 GS_VERSION_STR);
1489 }
1490
1491 /*
1492  * gs_setup
1493  *
1494  * Implements all the control endpoint functionality that's not
1495  * handled in hardware or the hardware driver.
1496  *
1497  * Returns the size of the data sent to the host, or a negative
1498  * error number.
1499  */
1500 static int gs_setup(struct usb_gadget *gadget,
1501         const struct usb_ctrlrequest *ctrl)
1502 {
1503         int ret = -EOPNOTSUPP;
1504         struct gs_dev *dev = get_gadget_data(gadget);
1505         struct usb_request *req = dev->dev_ctrl_req;
1506         u16 wIndex = le16_to_cpu(ctrl->wIndex);
1507         u16 wValue = le16_to_cpu(ctrl->wValue);
1508         u16 wLength = le16_to_cpu(ctrl->wLength);
1509
1510         req->complete = gs_setup_complete;
1511
1512         switch (ctrl->bRequestType & USB_TYPE_MASK) {
1513         case USB_TYPE_STANDARD:
1514                 ret = gs_setup_standard(gadget,ctrl);
1515                 break;
1516
1517         case USB_TYPE_CLASS:
1518                 ret = gs_setup_class(gadget,ctrl);
1519                 break;
1520
1521         default:
1522                 pr_err("gs_setup: unknown request, type=%02x, request=%02x, "
1523                         "value=%04x, index=%04x, length=%d\n",
1524                         ctrl->bRequestType, ctrl->bRequest,
1525                         wValue, wIndex, wLength);
1526                 break;
1527         }
1528
1529         /* respond with data transfer before status phase? */
1530         if (ret >= 0) {
1531                 req->length = ret;
1532                 req->zero = ret < wLength
1533                                 && (ret % gadget->ep0->maxpacket) == 0;
1534                 ret = usb_ep_queue(gadget->ep0, req, GFP_ATOMIC);
1535                 if (ret < 0) {
1536                         pr_err("gs_setup: cannot queue response, ret=%d\n",
1537                                 ret);
1538                         req->status = 0;
1539                         gs_setup_complete(gadget->ep0, req);
1540                 }
1541         }
1542
1543         /* device either stalls (ret < 0) or reports success */
1544         return ret;
1545 }
1546
1547 static int gs_setup_standard(struct usb_gadget *gadget,
1548         const struct usb_ctrlrequest *ctrl)
1549 {
1550         int ret = -EOPNOTSUPP;
1551         struct gs_dev *dev = get_gadget_data(gadget);
1552         struct usb_request *req = dev->dev_ctrl_req;
1553         u16 wIndex = le16_to_cpu(ctrl->wIndex);
1554         u16 wValue = le16_to_cpu(ctrl->wValue);
1555         u16 wLength = le16_to_cpu(ctrl->wLength);
1556
1557         switch (ctrl->bRequest) {
1558         case USB_REQ_GET_DESCRIPTOR:
1559                 if (ctrl->bRequestType != USB_DIR_IN)
1560                         break;
1561
1562                 switch (wValue >> 8) {
1563                 case USB_DT_DEVICE:
1564                         ret = min(wLength,
1565                                 (u16)sizeof(struct usb_device_descriptor));
1566                         memcpy(req->buf, &gs_device_desc, ret);
1567                         break;
1568
1569                 case USB_DT_DEVICE_QUALIFIER:
1570                         if (!gadget_is_dualspeed(gadget))
1571                                 break;
1572                         ret = min(wLength,
1573                                 (u16)sizeof(struct usb_qualifier_descriptor));
1574                         memcpy(req->buf, &gs_qualifier_desc, ret);
1575                         break;
1576
1577                 case USB_DT_OTHER_SPEED_CONFIG:
1578                         if (!gadget_is_dualspeed(gadget))
1579                                 break;
1580                         /* fall through */
1581                 case USB_DT_CONFIG:
1582                         ret = gs_build_config_buf(req->buf, gadget,
1583                                 wValue >> 8, wValue & 0xff,
1584                                 gadget_is_otg(gadget));
1585                         if (ret >= 0)
1586                                 ret = min(wLength, (u16)ret);
1587                         break;
1588
1589                 case USB_DT_STRING:
1590                         /* wIndex == language code. */
1591                         ret = usb_gadget_get_string(&gs_string_table,
1592                                 wValue & 0xff, req->buf);
1593                         if (ret >= 0)
1594                                 ret = min(wLength, (u16)ret);
1595                         break;
1596                 }
1597                 break;
1598
1599         case USB_REQ_SET_CONFIGURATION:
1600                 if (ctrl->bRequestType != 0)
1601                         break;
1602                 spin_lock(&dev->dev_lock);
1603                 ret = gs_set_config(dev, wValue);
1604                 spin_unlock(&dev->dev_lock);
1605                 break;
1606
1607         case USB_REQ_GET_CONFIGURATION:
1608                 if (ctrl->bRequestType != USB_DIR_IN)
1609                         break;
1610                 *(u8 *)req->buf = dev->dev_config;
1611                 ret = min(wLength, (u16)1);
1612                 break;
1613
1614         case USB_REQ_SET_INTERFACE:
1615                 if (ctrl->bRequestType != USB_RECIP_INTERFACE
1616                                 || !dev->dev_config
1617                                 || wIndex >= GS_MAX_NUM_INTERFACES)
1618                         break;
1619                 if (dev->dev_config == GS_BULK_CONFIG_ID
1620                                 && wIndex != GS_BULK_INTERFACE_ID)
1621                         break;
1622                 /* no alternate interface settings */
1623                 if (wValue != 0)
1624                         break;
1625                 spin_lock(&dev->dev_lock);
1626                 /* PXA hardware partially handles SET_INTERFACE;
1627                  * we need to kluge around that interference.  */
1628                 if (gadget_is_pxa(gadget)) {
1629                         ret = gs_set_config(dev, use_acm ?
1630                                 GS_ACM_CONFIG_ID : GS_BULK_CONFIG_ID);
1631                         goto set_interface_done;
1632                 }
1633                 if (dev->dev_config != GS_BULK_CONFIG_ID
1634                                 && wIndex == GS_CONTROL_INTERFACE_ID) {
1635                         if (dev->dev_notify_ep) {
1636                                 usb_ep_disable(dev->dev_notify_ep);
1637                                 usb_ep_enable(dev->dev_notify_ep, dev->dev_notify_ep_desc);
1638                         }
1639                 } else {
1640                         usb_ep_disable(dev->dev_in_ep);
1641                         usb_ep_disable(dev->dev_out_ep);
1642                         usb_ep_enable(dev->dev_in_ep, dev->dev_in_ep_desc);
1643                         usb_ep_enable(dev->dev_out_ep, dev->dev_out_ep_desc);
1644                 }
1645                 ret = 0;
1646 set_interface_done:
1647                 spin_unlock(&dev->dev_lock);
1648                 break;
1649
1650         case USB_REQ_GET_INTERFACE:
1651                 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE)
1652                 || dev->dev_config == GS_NO_CONFIG_ID)
1653                         break;
1654                 if (wIndex >= GS_MAX_NUM_INTERFACES
1655                                 || (dev->dev_config == GS_BULK_CONFIG_ID
1656                                 && wIndex != GS_BULK_INTERFACE_ID)) {
1657                         ret = -EDOM;
1658                         break;
1659                 }
1660                 /* no alternate interface settings */
1661                 *(u8 *)req->buf = 0;
1662                 ret = min(wLength, (u16)1);
1663                 break;
1664
1665         default:
1666                 pr_err("gs_setup: unknown standard request, type=%02x, "
1667                         "request=%02x, value=%04x, index=%04x, length=%d\n",
1668                         ctrl->bRequestType, ctrl->bRequest,
1669                         wValue, wIndex, wLength);
1670                 break;
1671         }
1672
1673         return ret;
1674 }
1675
1676 static int gs_setup_class(struct usb_gadget *gadget,
1677         const struct usb_ctrlrequest *ctrl)
1678 {
1679         int ret = -EOPNOTSUPP;
1680         struct gs_dev *dev = get_gadget_data(gadget);
1681         struct gs_port *port = dev->dev_port[0];        /* ACM only has one port */
1682         struct usb_request *req = dev->dev_ctrl_req;
1683         u16 wIndex = le16_to_cpu(ctrl->wIndex);
1684         u16 wValue = le16_to_cpu(ctrl->wValue);
1685         u16 wLength = le16_to_cpu(ctrl->wLength);
1686
1687         switch (ctrl->bRequest) {
1688         case USB_CDC_REQ_SET_LINE_CODING:
1689                 if (wLength != sizeof(struct usb_cdc_line_coding))
1690                         break;
1691                 ret = wLength;
1692                 req->complete = gs_setup_complete_set_line_coding;
1693                 break;
1694
1695         case USB_CDC_REQ_GET_LINE_CODING:
1696                 ret = min_t(int, wLength, sizeof(struct usb_cdc_line_coding));
1697                 if (port) {
1698                         spin_lock(&port->port_lock);
1699                         memcpy(req->buf, &port->port_line_coding, ret);
1700                         spin_unlock(&port->port_lock);
1701                 }
1702                 break;
1703
1704         case USB_CDC_REQ_SET_CONTROL_LINE_STATE:
1705                 if (wLength != 0)
1706                         break;
1707                 ret = 0;
1708                 if (port) {
1709                         /* REVISIT:  we currently just remember this data.
1710                          * If we change that, update whatever hardware needs
1711                          * updating.
1712                          */
1713                         spin_lock(&port->port_lock);
1714                         port->port_handshake_bits = wValue;
1715                         spin_unlock(&port->port_lock);
1716                 }
1717                 break;
1718
1719         default:
1720                 /* NOTE:  strictly speaking, we should accept AT-commands
1721                  * using SEND_ENCPSULATED_COMMAND/GET_ENCAPSULATED_RESPONSE.
1722                  * But our call management descriptor says we don't handle
1723                  * call management, so we should be able to get by without
1724                  * handling those "required" commands (except by stalling).
1725                  */
1726                 pr_err("gs_setup: unknown class request, "
1727                                 "type=%02x, request=%02x, value=%04x, "
1728                                 "index=%04x, length=%d\n",
1729                         ctrl->bRequestType, ctrl->bRequest,
1730                         wValue, wIndex, wLength);
1731                 break;
1732         }
1733
1734         return ret;
1735 }
1736
1737 static void gs_setup_complete_set_line_coding(struct usb_ep *ep,
1738                 struct usb_request *req)
1739 {
1740         struct gs_dev *dev = ep->driver_data;
1741         struct gs_port *port = dev->dev_port[0]; /* ACM only has one port */
1742
1743         switch (req->status) {
1744         case 0:
1745                 /* normal completion */
1746                 if (req->actual != sizeof(port->port_line_coding))
1747                         usb_ep_set_halt(ep);
1748                 else if (port) {
1749                         struct usb_cdc_line_coding      *value = req->buf;
1750
1751                         /* REVISIT:  we currently just remember this data.
1752                          * If we change that, (a) validate it first, then
1753                          * (b) update whatever hardware needs updating.
1754                          */
1755                         spin_lock(&port->port_lock);
1756                         port->port_line_coding = *value;
1757                         spin_unlock(&port->port_lock);
1758                 }
1759                 break;
1760
1761         case -ESHUTDOWN:
1762                 /* disconnect */
1763                 gs_free_req(ep, req);
1764                 break;
1765
1766         default:
1767                 /* unexpected */
1768                 break;
1769         }
1770         return;
1771 }
1772
1773 /*
1774  * gs_setup_complete
1775  */
1776 static void gs_setup_complete(struct usb_ep *ep, struct usb_request *req)
1777 {
1778         if (req->status || req->actual != req->length) {
1779                 pr_err("gs_setup_complete: status error, status=%d, "
1780                         "actual=%d, length=%d\n",
1781                         req->status, req->actual, req->length);
1782         }
1783 }
1784
1785 /*
1786  * gs_disconnect
1787  *
1788  * Called when the device is disconnected.  Frees the closed
1789  * ports and disconnects open ports.  Open ports will be freed
1790  * on close.  Then reallocates the ports for the next connection.
1791  */
1792 static void gs_disconnect(struct usb_gadget *gadget)
1793 {
1794         unsigned long flags;
1795         struct gs_dev *dev = get_gadget_data(gadget);
1796
1797         spin_lock_irqsave(&dev->dev_lock, flags);
1798
1799         gs_reset_config(dev);
1800
1801         /* free closed ports and disconnect open ports */
1802         /* (open ports will be freed when closed) */
1803         gs_free_ports(dev);
1804
1805         /* re-allocate ports for the next connection */
1806         if (gs_alloc_ports(dev, GFP_ATOMIC) != 0)
1807                 pr_err("gs_disconnect: cannot re-allocate ports\n");
1808
1809         spin_unlock_irqrestore(&dev->dev_lock, flags);
1810
1811         pr_info("gs_disconnect: %s disconnected\n", GS_LONG_NAME);
1812 }
1813
1814 /*
1815  * gs_set_config
1816  *
1817  * Configures the device by enabling device specific
1818  * optimizations, setting up the endpoints, allocating
1819  * read and write requests and queuing read requests.
1820  *
1821  * The device lock must be held when calling this function.
1822  */
1823 static int gs_set_config(struct gs_dev *dev, unsigned config)
1824 {
1825         int i;
1826         int ret = 0;
1827         struct usb_gadget *gadget = dev->dev_gadget;
1828         struct usb_ep *ep;
1829         struct usb_endpoint_descriptor *ep_desc;
1830         struct usb_request *req;
1831         struct gs_req_entry *req_entry;
1832
1833         if (dev == NULL) {
1834                 pr_err("gs_set_config: NULL device pointer\n");
1835                 return 0;
1836         }
1837
1838         if (config == dev->dev_config)
1839                 return 0;
1840
1841         gs_reset_config(dev);
1842
1843         switch (config) {
1844         case GS_NO_CONFIG_ID:
1845                 return 0;
1846         case GS_BULK_CONFIG_ID:
1847                 if (use_acm)
1848                         return -EINVAL;
1849                 /* device specific optimizations */
1850                 if (gadget_is_net2280(gadget))
1851                         net2280_set_fifo_mode(gadget, 1);
1852                 break;
1853         case GS_ACM_CONFIG_ID:
1854                 if (!use_acm)
1855                         return -EINVAL;
1856                 /* device specific optimizations */
1857                 if (gadget_is_net2280(gadget))
1858                         net2280_set_fifo_mode(gadget, 1);
1859                 break;
1860         default:
1861                 return -EINVAL;
1862         }
1863
1864         dev->dev_config = config;
1865
1866         gadget_for_each_ep(ep, gadget) {
1867
1868                 if (EP_NOTIFY_NAME
1869                 && strcmp(ep->name, EP_NOTIFY_NAME) == 0) {
1870                         ep_desc = choose_ep_desc(gadget,
1871                                 &gs_highspeed_notify_desc,
1872                                 &gs_fullspeed_notify_desc);
1873                         ret = usb_ep_enable(ep,ep_desc);
1874                         if (ret == 0) {
1875                                 ep->driver_data = dev;
1876                                 dev->dev_notify_ep = ep;
1877                                 dev->dev_notify_ep_desc = ep_desc;
1878                         } else {
1879                                 pr_err("gs_set_config: cannot enable NOTIFY "
1880                                         "endpoint %s, ret=%d\n",
1881                                         ep->name, ret);
1882                                 goto exit_reset_config;
1883                         }
1884                 }
1885
1886                 else if (strcmp(ep->name, EP_IN_NAME) == 0) {
1887                         ep_desc = choose_ep_desc(gadget,
1888                                 &gs_highspeed_in_desc,
1889                                 &gs_fullspeed_in_desc);
1890                         ret = usb_ep_enable(ep,ep_desc);
1891                         if (ret == 0) {
1892                                 ep->driver_data = dev;
1893                                 dev->dev_in_ep = ep;
1894                                 dev->dev_in_ep_desc = ep_desc;
1895                         } else {
1896                                 pr_err("gs_set_config: cannot enable IN "
1897                                         "endpoint %s, ret=%d\n",
1898                                         ep->name, ret);
1899                                 goto exit_reset_config;
1900                         }
1901                 }
1902
1903                 else if (strcmp(ep->name, EP_OUT_NAME) == 0) {
1904                         ep_desc = choose_ep_desc(gadget,
1905                                 &gs_highspeed_out_desc,
1906                                 &gs_fullspeed_out_desc);
1907                         ret = usb_ep_enable(ep,ep_desc);
1908                         if (ret == 0) {
1909                                 ep->driver_data = dev;
1910                                 dev->dev_out_ep = ep;
1911                                 dev->dev_out_ep_desc = ep_desc;
1912                         } else {
1913                                 pr_err("gs_set_config: cannot enable OUT "
1914                                         "endpoint %s, ret=%d\n",
1915                                         ep->name, ret);
1916                                 goto exit_reset_config;
1917                         }
1918                 }
1919
1920         }
1921
1922         if (dev->dev_in_ep == NULL || dev->dev_out_ep == NULL
1923         || (config != GS_BULK_CONFIG_ID && dev->dev_notify_ep == NULL)) {
1924                 pr_err("gs_set_config: cannot find endpoints\n");
1925                 ret = -ENODEV;
1926                 goto exit_reset_config;
1927         }
1928
1929         /* allocate and queue read requests */
1930         ep = dev->dev_out_ep;
1931         for (i=0; i<read_q_size && ret == 0; i++) {
1932                 if ((req=gs_alloc_req(ep, ep->maxpacket, GFP_ATOMIC))) {
1933                         req->complete = gs_read_complete;
1934                         if ((ret=usb_ep_queue(ep, req, GFP_ATOMIC))) {
1935                                 pr_err("gs_set_config: cannot queue read "
1936                                         "request, ret=%d\n", ret);
1937                         }
1938                 } else {
1939                         pr_err("gs_set_config: cannot allocate "
1940                                         "read requests\n");
1941                         ret = -ENOMEM;
1942                         goto exit_reset_config;
1943                 }
1944         }
1945
1946         /* allocate write requests, and put on free list */
1947         ep = dev->dev_in_ep;
1948         for (i=0; i<write_q_size; i++) {
1949                 if ((req_entry=gs_alloc_req_entry(ep, ep->maxpacket, GFP_ATOMIC))) {
1950                         req_entry->re_req->complete = gs_write_complete;
1951                         list_add(&req_entry->re_entry, &dev->dev_req_list);
1952                 } else {
1953                         pr_err("gs_set_config: cannot allocate "
1954                                         "write requests\n");
1955                         ret = -ENOMEM;
1956                         goto exit_reset_config;
1957                 }
1958         }
1959
1960         /* REVISIT the ACM mode should be able to actually *issue* some
1961          * notifications, for at least serial state change events if
1962          * not also for network connection; say so in bmCapabilities.
1963          */
1964
1965         pr_info("gs_set_config: %s configured, %s speed %s config\n",
1966                 GS_LONG_NAME,
1967                 gadget->speed == USB_SPEED_HIGH ? "high" : "full",
1968                 config == GS_BULK_CONFIG_ID ? "BULK" : "CDC-ACM");
1969
1970         return 0;
1971
1972 exit_reset_config:
1973         gs_reset_config(dev);
1974         return ret;
1975 }
1976
1977 /*
1978  * gs_reset_config
1979  *
1980  * Mark the device as not configured, disable all endpoints,
1981  * which forces completion of pending I/O and frees queued
1982  * requests, and free the remaining write requests on the
1983  * free list.
1984  *
1985  * The device lock must be held when calling this function.
1986  */
1987 static void gs_reset_config(struct gs_dev *dev)
1988 {
1989         struct gs_req_entry *req_entry;
1990
1991         if (dev == NULL) {
1992                 pr_err("gs_reset_config: NULL device pointer\n");
1993                 return;
1994         }
1995
1996         if (dev->dev_config == GS_NO_CONFIG_ID)
1997                 return;
1998
1999         dev->dev_config = GS_NO_CONFIG_ID;
2000
2001         /* free write requests on the free list */
2002         while(!list_empty(&dev->dev_req_list)) {
2003                 req_entry = list_entry(dev->dev_req_list.next,
2004                         struct gs_req_entry, re_entry);
2005                 list_del(&req_entry->re_entry);
2006                 gs_free_req_entry(dev->dev_in_ep, req_entry);
2007         }
2008
2009         /* disable endpoints, forcing completion of pending i/o; */
2010         /* completion handlers free their requests in this case */
2011         if (dev->dev_notify_ep) {
2012                 usb_ep_disable(dev->dev_notify_ep);
2013                 dev->dev_notify_ep = NULL;
2014         }
2015         if (dev->dev_in_ep) {
2016                 usb_ep_disable(dev->dev_in_ep);
2017                 dev->dev_in_ep = NULL;
2018         }
2019         if (dev->dev_out_ep) {
2020                 usb_ep_disable(dev->dev_out_ep);
2021                 dev->dev_out_ep = NULL;
2022         }
2023 }
2024
2025 /*
2026  * gs_build_config_buf
2027  *
2028  * Builds the config descriptors in the given buffer and returns the
2029  * length, or a negative error number.
2030  */
2031 static int gs_build_config_buf(u8 *buf, struct usb_gadget *g,
2032         u8 type, unsigned int index, int is_otg)
2033 {
2034         int len;
2035         int high_speed = 0;
2036         const struct usb_config_descriptor *config_desc;
2037         const struct usb_descriptor_header **function;
2038
2039         if (index >= gs_device_desc.bNumConfigurations)
2040                 return -EINVAL;
2041
2042         /* other speed switches high and full speed */
2043         if (gadget_is_dualspeed(g)) {
2044                 high_speed = (g->speed == USB_SPEED_HIGH);
2045                 if (type == USB_DT_OTHER_SPEED_CONFIG)
2046                         high_speed = !high_speed;
2047         }
2048
2049         if (use_acm) {
2050                 config_desc = &gs_acm_config_desc;
2051                 function = high_speed
2052                         ? gs_acm_highspeed_function
2053                         : gs_acm_fullspeed_function;
2054         } else {
2055                 config_desc = &gs_bulk_config_desc;
2056                 function = high_speed
2057                         ? gs_bulk_highspeed_function
2058                         : gs_bulk_fullspeed_function;
2059         }
2060
2061         /* for now, don't advertise srp-only devices */
2062         if (!is_otg)
2063                 function++;
2064
2065         len = usb_gadget_config_buf(config_desc, buf, GS_MAX_DESC_LEN, function);
2066         if (len < 0)
2067                 return len;
2068
2069         ((struct usb_config_descriptor *)buf)->bDescriptorType = type;
2070
2071         return len;
2072 }
2073
2074 /*
2075  * gs_alloc_req
2076  *
2077  * Allocate a usb_request and its buffer.  Returns a pointer to the
2078  * usb_request or NULL if there is an error.
2079  */
2080 static struct usb_request *
2081 gs_alloc_req(struct usb_ep *ep, unsigned int len, gfp_t kmalloc_flags)
2082 {
2083         struct usb_request *req;
2084
2085         if (ep == NULL)
2086                 return NULL;
2087
2088         req = usb_ep_alloc_request(ep, kmalloc_flags);
2089
2090         if (req != NULL) {
2091                 req->length = len;
2092                 req->buf = kmalloc(len, kmalloc_flags);
2093                 if (req->buf == NULL) {
2094                         usb_ep_free_request(ep, req);
2095                         return NULL;
2096                 }
2097         }
2098
2099         return req;
2100 }
2101
2102 /*
2103  * gs_free_req
2104  *
2105  * Free a usb_request and its buffer.
2106  */
2107 static void gs_free_req(struct usb_ep *ep, struct usb_request *req)
2108 {
2109         if (ep != NULL && req != NULL) {
2110                 kfree(req->buf);
2111                 usb_ep_free_request(ep, req);
2112         }
2113 }
2114
2115 /*
2116  * gs_alloc_req_entry
2117  *
2118  * Allocates a request and its buffer, using the given
2119  * endpoint, buffer len, and kmalloc flags.
2120  */
2121 static struct gs_req_entry *
2122 gs_alloc_req_entry(struct usb_ep *ep, unsigned len, gfp_t kmalloc_flags)
2123 {
2124         struct gs_req_entry     *req;
2125
2126         req = kmalloc(sizeof(struct gs_req_entry), kmalloc_flags);
2127         if (req == NULL)
2128                 return NULL;
2129
2130         req->re_req = gs_alloc_req(ep, len, kmalloc_flags);
2131         if (req->re_req == NULL) {
2132                 kfree(req);
2133                 return NULL;
2134         }
2135
2136         req->re_req->context = req;
2137
2138         return req;
2139 }
2140
2141 /*
2142  * gs_free_req_entry
2143  *
2144  * Frees a request and its buffer.
2145  */
2146 static void gs_free_req_entry(struct usb_ep *ep, struct gs_req_entry *req)
2147 {
2148         if (ep != NULL && req != NULL) {
2149                 if (req->re_req != NULL)
2150                         gs_free_req(ep, req->re_req);
2151                 kfree(req);
2152         }
2153 }
2154
2155 /*
2156  * gs_alloc_ports
2157  *
2158  * Allocate all ports and set the gs_dev struct to point to them.
2159  * Return 0 if successful, or a negative error number.
2160  *
2161  * The device lock is normally held when calling this function.
2162  */
2163 static int gs_alloc_ports(struct gs_dev *dev, gfp_t kmalloc_flags)
2164 {
2165         int i;
2166         struct gs_port *port;
2167
2168         if (dev == NULL)
2169                 return -EIO;
2170
2171         for (i=0; i<GS_NUM_PORTS; i++) {
2172                 if ((port=kzalloc(sizeof(struct gs_port), kmalloc_flags)) == NULL)
2173                         return -ENOMEM;
2174
2175                 port->port_dev = dev;
2176                 port->port_num = i;
2177                 port->port_line_coding.dwDTERate = cpu_to_le32(GS_DEFAULT_DTE_RATE);
2178                 port->port_line_coding.bCharFormat = GS_DEFAULT_CHAR_FORMAT;
2179                 port->port_line_coding.bParityType = GS_DEFAULT_PARITY;
2180                 port->port_line_coding.bDataBits = GS_DEFAULT_DATA_BITS;
2181                 spin_lock_init(&port->port_lock);
2182                 init_waitqueue_head(&port->port_write_wait);
2183
2184                 dev->dev_port[i] = port;
2185         }
2186
2187         return 0;
2188 }
2189
2190 /*
2191  * gs_free_ports
2192  *
2193  * Free all closed ports.  Open ports are disconnected by
2194  * freeing their write buffers, setting their device pointers
2195  * and the pointers to them in the device to NULL.  These
2196  * ports will be freed when closed.
2197  *
2198  * The device lock is normally held when calling this function.
2199  */
2200 static void gs_free_ports(struct gs_dev *dev)
2201 {
2202         int i;
2203         unsigned long flags;
2204         struct gs_port *port;
2205
2206         if (dev == NULL)
2207                 return;
2208
2209         for (i=0; i<GS_NUM_PORTS; i++) {
2210                 if ((port=dev->dev_port[i]) != NULL) {
2211                         dev->dev_port[i] = NULL;
2212
2213                         spin_lock_irqsave(&port->port_lock, flags);
2214
2215                         if (port->port_write_buf != NULL) {
2216                                 gs_buf_free(port->port_write_buf);
2217                                 port->port_write_buf = NULL;
2218                         }
2219
2220                         if (port->port_open_count > 0 || port->port_in_use) {
2221                                 port->port_dev = NULL;
2222                                 wake_up_interruptible(&port->port_write_wait);
2223                                 if (port->port_tty) {
2224                                         tty_hangup(port->port_tty);
2225                                 }
2226                                 spin_unlock_irqrestore(&port->port_lock, flags);
2227                         } else {
2228                                 spin_unlock_irqrestore(&port->port_lock, flags);
2229                                 kfree(port);
2230                         }
2231
2232                 }
2233         }
2234 }
2235
2236 /* Circular Buffer */
2237
2238 /*
2239  * gs_buf_alloc
2240  *
2241  * Allocate a circular buffer and all associated memory.
2242  */
2243 static struct gs_buf *gs_buf_alloc(unsigned int size, gfp_t kmalloc_flags)
2244 {
2245         struct gs_buf *gb;
2246
2247         if (size == 0)
2248                 return NULL;
2249
2250         gb = kmalloc(sizeof(struct gs_buf), kmalloc_flags);
2251         if (gb == NULL)
2252                 return NULL;
2253
2254         gb->buf_buf = kmalloc(size, kmalloc_flags);
2255         if (gb->buf_buf == NULL) {
2256                 kfree(gb);
2257                 return NULL;
2258         }
2259
2260         gb->buf_size = size;
2261         gb->buf_get = gb->buf_put = gb->buf_buf;
2262
2263         return gb;
2264 }
2265
2266 /*
2267  * gs_buf_free
2268  *
2269  * Free the buffer and all associated memory.
2270  */
2271 static void gs_buf_free(struct gs_buf *gb)
2272 {
2273         if (gb) {
2274                 kfree(gb->buf_buf);
2275                 kfree(gb);
2276         }
2277 }
2278
2279 /*
2280  * gs_buf_clear
2281  *
2282  * Clear out all data in the circular buffer.
2283  */
2284 static void gs_buf_clear(struct gs_buf *gb)
2285 {
2286         if (gb != NULL)
2287                 gb->buf_get = gb->buf_put;
2288                 /* equivalent to a get of all data available */
2289 }
2290
2291 /*
2292  * gs_buf_data_avail
2293  *
2294  * Return the number of bytes of data available in the circular
2295  * buffer.
2296  */
2297 static unsigned int gs_buf_data_avail(struct gs_buf *gb)
2298 {
2299         if (gb != NULL)
2300                 return (gb->buf_size + gb->buf_put - gb->buf_get) % gb->buf_size;
2301         else
2302                 return 0;
2303 }
2304
2305 /*
2306  * gs_buf_space_avail
2307  *
2308  * Return the number of bytes of space available in the circular
2309  * buffer.
2310  */
2311 static unsigned int gs_buf_space_avail(struct gs_buf *gb)
2312 {
2313         if (gb != NULL)
2314                 return (gb->buf_size + gb->buf_get - gb->buf_put - 1) % gb->buf_size;
2315         else
2316                 return 0;
2317 }
2318
2319 /*
2320  * gs_buf_put
2321  *
2322  * Copy data data from a user buffer and put it into the circular buffer.
2323  * Restrict to the amount of space available.
2324  *
2325  * Return the number of bytes copied.
2326  */
2327 static unsigned int
2328 gs_buf_put(struct gs_buf *gb, const char *buf, unsigned int count)
2329 {
2330         unsigned int len;
2331
2332         if (gb == NULL)
2333                 return 0;
2334
2335         len  = gs_buf_space_avail(gb);
2336         if (count > len)
2337                 count = len;
2338
2339         if (count == 0)
2340                 return 0;
2341
2342         len = gb->buf_buf + gb->buf_size - gb->buf_put;
2343         if (count > len) {
2344                 memcpy(gb->buf_put, buf, len);
2345                 memcpy(gb->buf_buf, buf+len, count - len);
2346                 gb->buf_put = gb->buf_buf + count - len;
2347         } else {
2348                 memcpy(gb->buf_put, buf, count);
2349                 if (count < len)
2350                         gb->buf_put += count;
2351                 else /* count == len */
2352                         gb->buf_put = gb->buf_buf;
2353         }
2354
2355         return count;
2356 }
2357
2358 /*
2359  * gs_buf_get
2360  *
2361  * Get data from the circular buffer and copy to the given buffer.
2362  * Restrict to the amount of data available.
2363  *
2364  * Return the number of bytes copied.
2365  */
2366 static unsigned int
2367 gs_buf_get(struct gs_buf *gb, char *buf, unsigned int count)
2368 {
2369         unsigned int len;
2370
2371         if (gb == NULL)
2372                 return 0;
2373
2374         len = gs_buf_data_avail(gb);
2375         if (count > len)
2376                 count = len;
2377
2378         if (count == 0)
2379                 return 0;
2380
2381         len = gb->buf_buf + gb->buf_size - gb->buf_get;
2382         if (count > len) {
2383                 memcpy(buf, gb->buf_get, len);
2384                 memcpy(buf+len, gb->buf_buf, count - len);
2385                 gb->buf_get = gb->buf_buf + count - len;
2386         } else {
2387                 memcpy(buf, gb->buf_get, count);
2388                 if (count < len)
2389                         gb->buf_get += count;
2390                 else /* count == len */
2391                         gb->buf_get = gb->buf_buf;
2392         }
2393
2394         return count;
2395 }