include/linux/usb/serial.h

   1 /*
   2  * USB Serial Converter stuff
   3  *
   4  *      Copyright (C) 1999 - 2012
   5  *          Greg Kroah-Hartman (greg@kroah.com)
   6  *
   7  *      This program is free software; you can redistribute it and/or modify
   8  *      it under the terms of the GNU General Public License as published by
   9  *      the Free Software Foundation; version 2 of the License.
  10  *
  11  */
  12
  13 #ifndef __LINUX_USB_SERIAL_H
  14 #define __LINUX_USB_SERIAL_H
  15
  16 #include <linux/kref.h>
  17 #include <linux/mutex.h>
  18 #include <linux/serial.h>
  19 #include <linux/sysrq.h>
  20 #include <linux/kfifo.h>
  21
  22 /* The maximum number of ports one device can grab at once */
  23 #define MAX_NUM_PORTS           8
  24
  25 /* parity check flag */
  26 #define RELEVANT_IFLAG(iflag)   (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
  27
  28 /* USB serial flags */
  29 #define USB_SERIAL_WRITE_BUSY   0
  30
  31 /**
  32  * usb_serial_port: structure for the specific ports of a device.
  33  * @serial: pointer back to the struct usb_serial owner of this port.
  34  * @port: pointer to the corresponding tty_port for this port.
  35  * @lock: spinlock to grab when updating portions of this structure.
  36  * @minor: the minor number of the port
  37  * @port_number: the struct usb_serial port number of this port (starts at 0)
  38  * @interrupt_in_buffer: pointer to the interrupt in buffer for this port.
  39  * @interrupt_in_urb: pointer to the interrupt in struct urb for this port.
  40  * @interrupt_in_endpointAddress: endpoint address for the interrupt in pipe
  41  *      for this port.
  42  * @interrupt_out_buffer: pointer to the interrupt out buffer for this port.
  43  * @interrupt_out_size: the size of the interrupt_out_buffer, in bytes.
  44  * @interrupt_out_urb: pointer to the interrupt out struct urb for this port.
  45  * @interrupt_out_endpointAddress: endpoint address for the interrupt out pipe
  46  *      for this port.
  47  * @bulk_in_buffer: pointer to the bulk in buffer for this port.
  48  * @bulk_in_size: the size of the bulk_in_buffer, in bytes.
  49  * @read_urb: pointer to the bulk in struct urb for this port.
  50  * @bulk_in_endpointAddress: endpoint address for the bulk in pipe for this
  51  *      port.
  52  * @bulk_in_buffers: pointers to the bulk in buffers for this port
  53  * @read_urbs: pointers to the bulk in urbs for this port
  54  * @read_urbs_free: status bitmap the for bulk in urbs
  55  * @bulk_out_buffer: pointer to the bulk out buffer for this port.
  56  * @bulk_out_size: the size of the bulk_out_buffer, in bytes.
  57  * @write_urb: pointer to the bulk out struct urb for this port.
  58  * @write_fifo: kfifo used to buffer outgoing data
  59  * @bulk_out_buffers: pointers to the bulk out buffers for this port
  60  * @write_urbs: pointers to the bulk out urbs for this port
  61  * @write_urbs_free: status bitmap the for bulk out urbs
  62  * @icount: interrupt counters
  63  * @tx_bytes: number of bytes currently in host stack queues
  64  * @bulk_out_endpointAddress: endpoint address for the bulk out pipe for this
  65  *      port.
  66  * @flags: usb serial port flags
  67  * @write_wait: a wait_queue_head_t used by the port.
  68  * @work: work queue entry for the line discipline waking up.
  69  * @throttled: nonzero if the read urb is inactive to throttle the device
  70  * @throttle_req: nonzero if the tty wants to throttle us
  71  * @dev: pointer to the serial device
  72  *
  73  * This structure is used by the usb-serial core and drivers for the specific
  74  * ports of a device.
  75  */
  76 struct usb_serial_port {
  77         struct usb_serial       *serial;
  78         struct tty_port         port;
  79         spinlock_t              lock;
  80         u32                     minor;
  81         u8                      port_number;
  82
  83         unsigned char           *interrupt_in_buffer;
  84         struct urb              *interrupt_in_urb;
  85         __u8                    interrupt_in_endpointAddress;
  86
  87         unsigned char           *interrupt_out_buffer;
  88         int                     interrupt_out_size;
  89         struct urb              *interrupt_out_urb;
  90         __u8                    interrupt_out_endpointAddress;
  91
  92         unsigned char           *bulk_in_buffer;
  93         int                     bulk_in_size;
  94         struct urb              *read_urb;
  95         __u8                    bulk_in_endpointAddress;
  96
  97         unsigned char           *bulk_in_buffers[2];
  98         struct urb              *read_urbs[2];
  99         unsigned long           read_urbs_free;
 100
 101         unsigned char           *bulk_out_buffer;
 102         int                     bulk_out_size;
 103         struct urb              *write_urb;
 104         struct kfifo            write_fifo;
 105
 106         unsigned char           *bulk_out_buffers[2];
 107         struct urb              *write_urbs[2];
 108         unsigned long           write_urbs_free;
 109         __u8                    bulk_out_endpointAddress;
 110
 111         struct async_icount     icount;
 112         int                     tx_bytes;
 113
 114         unsigned long           flags;
 115         wait_queue_head_t       write_wait;
 116         struct work_struct      work;
 117         char                    throttled;
 118         char                    throttle_req;
 119         unsigned long           sysrq; /* sysrq timeout */
 120         struct device           dev;
 121 };
 122 #define to_usb_serial_port(d) container_of(d, struct usb_serial_port, dev)
 123
 124 /* get and set the port private data pointer helper functions */
 125 static inline void *usb_get_serial_port_data(struct usb_serial_port *port)
 126 {
 127         return dev_get_drvdata(&port->dev);
 128 }
 129
 130 static inline void usb_set_serial_port_data(struct usb_serial_port *port,
 131                                             void *data)
 132 {
 133         dev_set_drvdata(&port->dev, data);
 134 }
 135
 136 /**
 137  * usb_serial - structure used by the usb-serial core for a device
 138  * @dev: pointer to the struct usb_device for this device
 139  * @type: pointer to the struct usb_serial_driver for this device
 140  * @interface: pointer to the struct usb_interface for this device
 141  * @num_ports: the number of ports this device has
 142  * @num_interrupt_in: number of interrupt in endpoints we have
 143  * @num_interrupt_out: number of interrupt out endpoints we have
 144  * @num_bulk_in: number of bulk in endpoints we have
 145  * @num_bulk_out: number of bulk out endpoints we have
 146  * @port: array of struct usb_serial_port structures for the different ports.
 147  * @private: place to put any driver specific information that is needed.  The
 148  *      usb-serial driver is required to manage this data, the usb-serial core
 149  *      will not touch this.  Use usb_get_serial_data() and
 150  *      usb_set_serial_data() to access this.
 151  */
 152 struct usb_serial {
 153         struct usb_device               *dev;
 154         struct usb_serial_driver        *type;
 155         struct usb_interface            *interface;
 156         unsigned char                   disconnected:1;
 157         unsigned char                   suspending:1;
 158         unsigned char                   attached:1;
 159         unsigned char                   minors_reserved:1;
 160         unsigned char                   num_ports;
 161         unsigned char                   num_port_pointers;
 162         char                            num_interrupt_in;
 163         char                            num_interrupt_out;
 164         char                            num_bulk_in;
 165         char                            num_bulk_out;
 166         struct usb_serial_port          *port[MAX_NUM_PORTS];
 167         struct kref                     kref;
 168         struct mutex                    disc_mutex;
 169         void                            *private;
 170 };
 171 #define to_usb_serial(d) container_of(d, struct usb_serial, kref)
 172
 173 /* get and set the serial private data pointer helper functions */
 174 static inline void *usb_get_serial_data(struct usb_serial *serial)
 175 {
 176         return serial->private;
 177 }
 178
 179 static inline void usb_set_serial_data(struct usb_serial *serial, void *data)
 180 {
 181         serial->private = data;
 182 }
 183
 184 /**
 185  * usb_serial_driver - describes a usb serial driver
 186  * @description: pointer to a string that describes this driver.  This string
 187  *      used in the syslog messages when a device is inserted or removed.
 188  * @id_table: pointer to a list of usb_device_id structures that define all
 189  *      of the devices this structure can support.
 190  * @num_ports: the number of different ports this device will have.
 191  * @bulk_in_size: minimum number of bytes to allocate for bulk-in buffer
 192  *      (0 = end-point size)
 193  * @bulk_out_size: minimum number of bytes to allocate for bulk-out buffer
 194  *      (0 = end-point size)
 195  * @calc_num_ports: pointer to a function to determine how many ports this
 196  *      device has dynamically.  It will be called after the probe()
 197  *      callback is called, but before attach()
 198  * @probe: pointer to the driver's probe function.
 199  *      This will be called when the device is inserted into the system,
 200  *      but before the device has been fully initialized by the usb_serial
 201  *      subsystem.  Use this function to download any firmware to the device,
 202  *      or any other early initialization that might be needed.
 203  *      Return 0 to continue on with the initialization sequence.  Anything
 204  *      else will abort it.
 205  * @attach: pointer to the driver's attach function.
 206  *      This will be called when the struct usb_serial structure is fully set
 207  *      set up.  Do any local initialization of the device, or any private
 208  *      memory structure allocation at this point in time.
 209  * @disconnect: pointer to the driver's disconnect function.  This will be
 210  *      called when the device is unplugged or unbound from the driver.
 211  * @release: pointer to the driver's release function.  This will be called
 212  *      when the usb_serial data structure is about to be destroyed.
 213  * @usb_driver: pointer to the struct usb_driver that controls this
 214  *      device.  This is necessary to allow dynamic ids to be added to
 215  *      the driver from sysfs.
 216  *
 217  * This structure is defines a USB Serial driver.  It provides all of
 218  * the information that the USB serial core code needs.  If the function
 219  * pointers are defined, then the USB serial core code will call them when
 220  * the corresponding tty port functions are called.  If they are not
 221  * called, the generic serial function will be used instead.
 222  *
 223  * The driver.owner field should be set to the module owner of this driver.
 224  * The driver.name field should be set to the name of this driver (remember
 225  * it will show up in sysfs, so it needs to be short and to the point.
 226  * Using the module name is a good idea.)
 227  */
 228 struct usb_serial_driver {
 229         const char *description;
 230         const struct usb_device_id *id_table;
 231         char    num_ports;
 232
 233         struct list_head        driver_list;
 234         struct device_driver    driver;
 235         struct usb_driver       *usb_driver;
 236         struct usb_dynids       dynids;
 237
 238         size_t                  bulk_in_size;
 239         size_t                  bulk_out_size;
 240
 241         int (*probe)(struct usb_serial *serial, const struct usb_device_id *id);
 242         int (*attach)(struct usb_serial *serial);
 243         int (*calc_num_ports) (struct usb_serial *serial);
 244
 245         void (*disconnect)(struct usb_serial *serial);
 246         void (*release)(struct usb_serial *serial);
 247
 248         int (*port_probe)(struct usb_serial_port *port);
 249         int (*port_remove)(struct usb_serial_port *port);
 250
 251         int (*suspend)(struct usb_serial *serial, pm_message_t message);
 252         int (*resume)(struct usb_serial *serial);
 253         int (*reset_resume)(struct usb_serial *serial);
 254
 255         /* serial function calls */
 256         /* Called by console and by the tty layer */
 257         int  (*open)(struct tty_struct *tty, struct usb_serial_port *port);
 258         void (*close)(struct usb_serial_port *port);
 259         int  (*write)(struct tty_struct *tty, struct usb_serial_port *port,
 260                         const unsigned char *buf, int count);
 261         /* Called only by the tty layer */
 262         int  (*write_room)(struct tty_struct *tty);
 263         int  (*ioctl)(struct tty_struct *tty,
 264                       unsigned int cmd, unsigned long arg);
 265         void (*set_termios)(struct tty_struct *tty,
 266                         struct usb_serial_port *port, struct ktermios *old);
 267         void (*break_ctl)(struct tty_struct *tty, int break_state);
 268         int  (*chars_in_buffer)(struct tty_struct *tty);
 269         void (*wait_until_sent)(struct tty_struct *tty, long timeout);
 270         bool (*tx_empty)(struct usb_serial_port *port);
 271         void (*throttle)(struct tty_struct *tty);
 272         void (*unthrottle)(struct tty_struct *tty);
 273         int  (*tiocmget)(struct tty_struct *tty);
 274         int  (*tiocmset)(struct tty_struct *tty,
 275                          unsigned int set, unsigned int clear);
 276         int  (*tiocmiwait)(struct tty_struct *tty, unsigned long arg);
 277         int  (*get_icount)(struct tty_struct *tty,
 278                         struct serial_icounter_struct *icount);
 279         /* Called by the tty layer for port level work. There may or may not
 280            be an attached tty at this point */
 281         void (*dtr_rts)(struct usb_serial_port *port, int on);
 282         int  (*carrier_raised)(struct usb_serial_port *port);
 283         /* Called by the usb serial hooks to allow the user to rework the
 284            termios state */
 285         void (*init_termios)(struct tty_struct *tty);
 286         /* USB events */
 287         void (*read_int_callback)(struct urb *urb);
 288         void (*write_int_callback)(struct urb *urb);
 289         void (*read_bulk_callback)(struct urb *urb);
 290         void (*write_bulk_callback)(struct urb *urb);
 291         /* Called by the generic read bulk callback */
 292         void (*process_read_urb)(struct urb *urb);
 293         /* Called by the generic write implementation */
 294         int (*prepare_write_buffer)(struct usb_serial_port *port,
 295                                                 void *dest, size_t size);
 296 };
 297 #define to_usb_serial_driver(d) \
 298         container_of(d, struct usb_serial_driver, driver)
 299
 300 extern int usb_serial_register_drivers(struct usb_serial_driver *const serial_drivers[],
 301                 const char *name, const struct usb_device_id *id_table);
 302 extern void usb_serial_deregister_drivers(struct usb_serial_driver *const serial_drivers[]);
 303 extern void usb_serial_port_softint(struct usb_serial_port *port);
 304
 305 extern int usb_serial_suspend(struct usb_interface *intf, pm_message_t message);
 306 extern int usb_serial_resume(struct usb_interface *intf);
 307
 308 /* USB Serial console functions */
 309 #ifdef CONFIG_USB_SERIAL_CONSOLE
 310 extern void usb_serial_console_init(int minor);
 311 extern void usb_serial_console_exit(void);
 312 extern void usb_serial_console_disconnect(struct usb_serial *serial);
 313 #else
 314 static inline void usb_serial_console_init(int minor) { }
 315 static inline void usb_serial_console_exit(void) { }
 316 static inline void usb_serial_console_disconnect(struct usb_serial *serial) {}
 317 #endif
 318
 319 /* Functions needed by other parts of the usbserial core */
 320 extern struct usb_serial_port *usb_serial_port_get_by_minor(unsigned int minor);
 321 extern void usb_serial_put(struct usb_serial *serial);
 322 extern int usb_serial_generic_open(struct tty_struct *tty,
 323         struct usb_serial_port *port);
 324 extern int usb_serial_generic_write_start(struct usb_serial_port *port,
 325                                                         gfp_t mem_flags);
 326 extern int usb_serial_generic_write(struct tty_struct *tty,
 327         struct usb_serial_port *port, const unsigned char *buf, int count);
 328 extern void usb_serial_generic_close(struct usb_serial_port *port);
 329 extern int usb_serial_generic_resume(struct usb_serial *serial);
 330 extern int usb_serial_generic_write_room(struct tty_struct *tty);
 331 extern int usb_serial_generic_chars_in_buffer(struct tty_struct *tty);
 332 extern void usb_serial_generic_wait_until_sent(struct tty_struct *tty,
 333                                                                 long timeout);
 334 extern void usb_serial_generic_read_bulk_callback(struct urb *urb);
 335 extern void usb_serial_generic_write_bulk_callback(struct urb *urb);
 336 extern void usb_serial_generic_throttle(struct tty_struct *tty);
 337 extern void usb_serial_generic_unthrottle(struct tty_struct *tty);
 338 extern int usb_serial_generic_tiocmiwait(struct tty_struct *tty,
 339                                                         unsigned long arg);
 340 extern int usb_serial_generic_get_icount(struct tty_struct *tty,
 341                                         struct serial_icounter_struct *icount);
 342 extern int usb_serial_generic_register(void);
 343 extern void usb_serial_generic_deregister(void);
 344 extern int usb_serial_generic_submit_read_urbs(struct usb_serial_port *port,
 345                                                  gfp_t mem_flags);
 346 extern void usb_serial_generic_process_read_urb(struct urb *urb);
 347 extern int usb_serial_generic_prepare_write_buffer(struct usb_serial_port *port,
 348                                                 void *dest, size_t size);
 349 extern int usb_serial_handle_sysrq_char(struct usb_serial_port *port,
 350                                         unsigned int ch);
 351 extern int usb_serial_handle_break(struct usb_serial_port *port);
 352 extern void usb_serial_handle_dcd_change(struct usb_serial_port *usb_port,
 353                                          struct tty_struct *tty,
 354                                          unsigned int status);
 355
 356
 357 extern int usb_serial_bus_register(struct usb_serial_driver *device);
 358 extern void usb_serial_bus_deregister(struct usb_serial_driver *device);
 359
 360 extern struct usb_serial_driver usb_serial_generic_device;
 361 extern struct bus_type usb_serial_bus_type;
 362 extern struct tty_driver *usb_serial_tty_driver;
 363
 364 static inline void usb_serial_debug_data(struct device *dev,
 365                                          const char *function, int size,
 366                                          const unsigned char *data)
 367 {
 368         dev_dbg(dev, "%s - length = %d, data = %*ph\n",
 369                 function, size, size, data);
 370 }
 371
 372 /*
 373  * Macro for reporting errors in write path to avoid inifinite loop
 374  * when port is used as a console.
 375  */
 376 #define dev_err_console(usport, fmt, ...)                               \
 377 do {                                                                    \
 378         static bool __print_once;                                       \
 379         struct usb_serial_port *__port = (usport);                      \
 380                                                                         \
 381         if (!__port->port.console || !__print_once) {                   \
 382                 __print_once = true;                                    \
 383                 dev_err(&__port->dev, fmt, ##__VA_ARGS__);              \
 384         }                                                               \
 385 } while (0)
 386
 387 /*
 388  * module_usb_serial_driver() - Helper macro for registering a USB Serial driver
 389  * @__serial_drivers: list of usb_serial drivers to register
 390  * @__ids: all device ids that @__serial_drivers bind to
 391  *
 392  * Helper macro for USB serial drivers which do not do anything special
 393  * in module init/exit. This eliminates a lot of boilerplate. Each
 394  * module may only use this macro once, and calling it replaces
 395  * module_init() and module_exit()
 396  *
 397  */
 398 #define usb_serial_module_driver(__name, __serial_drivers, __ids)       \
 399 static int __init usb_serial_module_init(void)                          \
 400 {                                                                       \
 401         return usb_serial_register_drivers(__serial_drivers,            \
 402                                            __name, __ids);              \
 403 }                                                                       \
 404 module_init(usb_serial_module_init);                                    \
 405 static void __exit usb_serial_module_exit(void)                         \
 406 {                                                                       \
 407         usb_serial_deregister_drivers(__serial_drivers);                \
 408 }                                                                       \
 409 module_exit(usb_serial_module_exit);
 410
 411 #define module_usb_serial_driver(__serial_drivers, __ids)               \
 412         usb_serial_module_driver(KBUILD_MODNAME, __serial_drivers, __ids)
 413
 414 #endif /* __LINUX_USB_SERIAL_H */
 415