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: bytes to allocate for bulk-out buffer (0 = end-point size)
 194  * @calc_num_ports: pointer to a function to determine how many ports this
 195  *      device has dynamically.  It will be called after the probe()
 196  *      callback is called, but before attach()
 197  * @probe: pointer to the driver's probe function.
 198  *      This will be called when the device is inserted into the system,
 199  *      but before the device has been fully initialized by the usb_serial
 200  *      subsystem.  Use this function to download any firmware to the device,
 201  *      or any other early initialization that might be needed.
 202  *      Return 0 to continue on with the initialization sequence.  Anything
 203  *      else will abort it.
 204  * @attach: pointer to the driver's attach function.
 205  *      This will be called when the struct usb_serial structure is fully set
 206  *      set up.  Do any local initialization of the device, or any private
 207  *      memory structure allocation at this point in time.
 208  * @disconnect: pointer to the driver's disconnect function.  This will be
 209  *      called when the device is unplugged or unbound from the driver.
 210  * @release: pointer to the driver's release function.  This will be called
 211  *      when the usb_serial data structure is about to be destroyed.
 212  * @usb_driver: pointer to the struct usb_driver that controls this
 213  *      device.  This is necessary to allow dynamic ids to be added to
 214  *      the driver from sysfs.
 215  *
 216  * This structure is defines a USB Serial driver.  It provides all of
 217  * the information that the USB serial core code needs.  If the function
 218  * pointers are defined, then the USB serial core code will call them when
 219  * the corresponding tty port functions are called.  If they are not
 220  * called, the generic serial function will be used instead.
 221  *
 222  * The driver.owner field should be set to the module owner of this driver.
 223  * The driver.name field should be set to the name of this driver (remember
 224  * it will show up in sysfs, so it needs to be short and to the point.
 225  * Using the module name is a good idea.)
 226  */
 227 struct usb_serial_driver {
 228         const char *description;
 229         const struct usb_device_id *id_table;
 230         char    num_ports;
 231
 232         struct list_head        driver_list;
 233         struct device_driver    driver;
 234         struct usb_driver       *usb_driver;
 235         struct usb_dynids       dynids;
 236
 237         size_t                  bulk_in_size;
 238         size_t                  bulk_out_size;
 239
 240         int (*probe)(struct usb_serial *serial, const struct usb_device_id *id);
 241         int (*attach)(struct usb_serial *serial);
 242         int (*calc_num_ports) (struct usb_serial *serial);
 243
 244         void (*disconnect)(struct usb_serial *serial);
 245         void (*release)(struct usb_serial *serial);
 246
 247         int (*port_probe)(struct usb_serial_port *port);
 248         int (*port_remove)(struct usb_serial_port *port);
 249
 250         int (*suspend)(struct usb_serial *serial, pm_message_t message);
 251         int (*resume)(struct usb_serial *serial);
 252         int (*reset_resume)(struct usb_serial *serial);
 253
 254         /* serial function calls */
 255         /* Called by console and by the tty layer */
 256         int  (*open)(struct tty_struct *tty, struct usb_serial_port *port);
 257         void (*close)(struct usb_serial_port *port);
 258         int  (*write)(struct tty_struct *tty, struct usb_serial_port *port,
 259                         const unsigned char *buf, int count);
 260         /* Called only by the tty layer */
 261         int  (*write_room)(struct tty_struct *tty);
 262         int  (*ioctl)(struct tty_struct *tty,
 263                       unsigned int cmd, unsigned long arg);
 264         void (*set_termios)(struct tty_struct *tty,
 265                         struct usb_serial_port *port, struct ktermios *old);
 266         void (*break_ctl)(struct tty_struct *tty, int break_state);
 267         int  (*chars_in_buffer)(struct tty_struct *tty);
 268         void (*wait_until_sent)(struct tty_struct *tty, long timeout);
 269         bool (*tx_empty)(struct usb_serial_port *port);
 270         void (*throttle)(struct tty_struct *tty);
 271         void (*unthrottle)(struct tty_struct *tty);
 272         int  (*tiocmget)(struct tty_struct *tty);
 273         int  (*tiocmset)(struct tty_struct *tty,
 274                          unsigned int set, unsigned int clear);
 275         int  (*tiocmiwait)(struct tty_struct *tty, unsigned long arg);
 276         int  (*get_icount)(struct tty_struct *tty,
 277                         struct serial_icounter_struct *icount);
 278         /* Called by the tty layer for port level work. There may or may not
 279            be an attached tty at this point */
 280         void (*dtr_rts)(struct usb_serial_port *port, int on);
 281         int  (*carrier_raised)(struct usb_serial_port *port);
 282         /* Called by the usb serial hooks to allow the user to rework the
 283            termios state */
 284         void (*init_termios)(struct tty_struct *tty);
 285         /* USB events */
 286         void (*read_int_callback)(struct urb *urb);
 287         void (*write_int_callback)(struct urb *urb);
 288         void (*read_bulk_callback)(struct urb *urb);
 289         void (*write_bulk_callback)(struct urb *urb);
 290         /* Called by the generic read bulk callback */
 291         void (*process_read_urb)(struct urb *urb);
 292         /* Called by the generic write implementation */
 293         int (*prepare_write_buffer)(struct usb_serial_port *port,
 294                                                 void *dest, size_t size);
 295 };
 296 #define to_usb_serial_driver(d) \
 297         container_of(d, struct usb_serial_driver, driver)
 298
 299 extern int usb_serial_register_drivers(struct usb_serial_driver *const serial_drivers[],
 300                 const char *name, const struct usb_device_id *id_table);
 301 extern void usb_serial_deregister_drivers(struct usb_serial_driver *const serial_drivers[]);
 302 extern void usb_serial_port_softint(struct usb_serial_port *port);
 303
 304 extern int usb_serial_suspend(struct usb_interface *intf, pm_message_t message);
 305 extern int usb_serial_resume(struct usb_interface *intf);
 306
 307 /* USB Serial console functions */
 308 #ifdef CONFIG_USB_SERIAL_CONSOLE
 309 extern void usb_serial_console_init(int minor);
 310 extern void usb_serial_console_exit(void);
 311 extern void usb_serial_console_disconnect(struct usb_serial *serial);
 312 #else
 313 static inline void usb_serial_console_init(int minor) { }
 314 static inline void usb_serial_console_exit(void) { }
 315 static inline void usb_serial_console_disconnect(struct usb_serial *serial) {}
 316 #endif
 317
 318 /* Functions needed by other parts of the usbserial core */
 319 extern struct usb_serial_port *usb_serial_port_get_by_minor(unsigned int minor);
 320 extern void usb_serial_put(struct usb_serial *serial);
 321 extern int usb_serial_generic_open(struct tty_struct *tty,
 322         struct usb_serial_port *port);
 323 extern int usb_serial_generic_write_start(struct usb_serial_port *port,
 324                                                         gfp_t mem_flags);
 325 extern int usb_serial_generic_write(struct tty_struct *tty,
 326         struct usb_serial_port *port, const unsigned char *buf, int count);
 327 extern void usb_serial_generic_close(struct usb_serial_port *port);
 328 extern int usb_serial_generic_resume(struct usb_serial *serial);
 329 extern int usb_serial_generic_write_room(struct tty_struct *tty);
 330 extern int usb_serial_generic_chars_in_buffer(struct tty_struct *tty);
 331 extern void usb_serial_generic_wait_until_sent(struct tty_struct *tty,
 332                                                                 long timeout);
 333 extern void usb_serial_generic_read_bulk_callback(struct urb *urb);
 334 extern void usb_serial_generic_write_bulk_callback(struct urb *urb);
 335 extern void usb_serial_generic_throttle(struct tty_struct *tty);
 336 extern void usb_serial_generic_unthrottle(struct tty_struct *tty);
 337 extern int usb_serial_generic_tiocmiwait(struct tty_struct *tty,
 338                                                         unsigned long arg);
 339 extern int usb_serial_generic_get_icount(struct tty_struct *tty,
 340                                         struct serial_icounter_struct *icount);
 341 extern int usb_serial_generic_register(void);
 342 extern void usb_serial_generic_deregister(void);
 343 extern int usb_serial_generic_submit_read_urbs(struct usb_serial_port *port,
 344                                                  gfp_t mem_flags);
 345 extern void usb_serial_generic_process_read_urb(struct urb *urb);
 346 extern int usb_serial_generic_prepare_write_buffer(struct usb_serial_port *port,
 347                                                 void *dest, size_t size);
 348 extern int usb_serial_handle_sysrq_char(struct usb_serial_port *port,
 349                                         unsigned int ch);
 350 extern int usb_serial_handle_break(struct usb_serial_port *port);
 351 extern void usb_serial_handle_dcd_change(struct usb_serial_port *usb_port,
 352                                          struct tty_struct *tty,
 353                                          unsigned int status);
 354
 355
 356 extern int usb_serial_bus_register(struct usb_serial_driver *device);
 357 extern void usb_serial_bus_deregister(struct usb_serial_driver *device);
 358
 359 extern struct usb_serial_driver usb_serial_generic_device;
 360 extern struct bus_type usb_serial_bus_type;
 361 extern struct tty_driver *usb_serial_tty_driver;
 362
 363 static inline void usb_serial_debug_data(struct device *dev,
 364                                          const char *function, int size,
 365                                          const unsigned char *data)
 366 {
 367         dev_dbg(dev, "%s - length = %d, data = %*ph\n",
 368                 function, size, size, data);
 369 }
 370
 371 /*
 372  * Macro for reporting errors in write path to avoid inifinite loop
 373  * when port is used as a console.
 374  */
 375 #define dev_err_console(usport, fmt, ...)                               \
 376 do {                                                                    \
 377         static bool __print_once;                                       \
 378         struct usb_serial_port *__port = (usport);                      \
 379                                                                         \
 380         if (!__port->port.console || !__print_once) {                   \
 381                 __print_once = true;                                    \
 382                 dev_err(&__port->dev, fmt, ##__VA_ARGS__);              \
 383         }                                                               \
 384 } while (0)
 385
 386 /*
 387  * module_usb_serial_driver() - Helper macro for registering a USB Serial driver
 388  * @__serial_drivers: list of usb_serial drivers to register
 389  * @__ids: all device ids that @__serial_drivers bind to
 390  *
 391  * Helper macro for USB serial drivers which do not do anything special
 392  * in module init/exit. This eliminates a lot of boilerplate. Each
 393  * module may only use this macro once, and calling it replaces
 394  * module_init() and module_exit()
 395  *
 396  */
 397 #define usb_serial_module_driver(__name, __serial_drivers, __ids)       \
 398 static int __init usb_serial_module_init(void)                          \
 399 {                                                                       \
 400         return usb_serial_register_drivers(__serial_drivers,            \
 401                                            __name, __ids);              \
 402 }                                                                       \
 403 module_init(usb_serial_module_init);                                    \
 404 static void __exit usb_serial_module_exit(void)                         \
 405 {                                                                       \
 406         usb_serial_deregister_drivers(__serial_drivers);                \
 407 }                                                                       \
 408 module_exit(usb_serial_module_exit);
 409
 410 #define module_usb_serial_driver(__serial_drivers, __ids)               \
 411         usb_serial_module_driver(KBUILD_MODNAME, __serial_drivers, __ids)
 412
 413 #endif /* __LINUX_USB_SERIAL_H */
 414