1 /* 2 * Fintek F81232 USB to serial adaptor driver 3 * 4 * Copyright (C) 2012 Greg Kroah-Hartman (gregkh@linuxfoundation.org) 5 * Copyright (C) 2012 Linux Foundation 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License version 2 as published by 9 * the Free Software Foundation. 10 * 11 */ 12 13 #include <linux/kernel.h> 14 #include <linux/errno.h> 15 #include <linux/init.h> 16 #include <linux/slab.h> 17 #include <linux/tty.h> 18 #include <linux/tty_driver.h> 19 #include <linux/tty_flip.h> 20 #include <linux/serial.h> 21 #include <linux/module.h> 22 #include <linux/moduleparam.h> 23 #include <linux/spinlock.h> 24 #include <linux/uaccess.h> 25 #include <linux/usb.h> 26 #include <linux/usb/serial.h> 27 28 static bool debug; 29 30 static const struct usb_device_id id_table[] = { 31 { USB_DEVICE(0x1934, 0x0706) }, 32 { } /* Terminating entry */ 33 }; 34 MODULE_DEVICE_TABLE(usb, id_table); 35 36 #define CONTROL_DTR 0x01 37 #define CONTROL_RTS 0x02 38 39 #define UART_STATE 0x08 40 #define UART_STATE_TRANSIENT_MASK 0x74 41 #define UART_DCD 0x01 42 #define UART_DSR 0x02 43 #define UART_BREAK_ERROR 0x04 44 #define UART_RING 0x08 45 #define UART_FRAME_ERROR 0x10 46 #define UART_PARITY_ERROR 0x20 47 #define UART_OVERRUN_ERROR 0x40 48 #define UART_CTS 0x80 49 50 struct f81232_private { 51 spinlock_t lock; 52 wait_queue_head_t delta_msr_wait; 53 u8 line_control; 54 u8 line_status; 55 }; 56 57 static void f81232_update_line_status(struct usb_serial_port *port, 58 unsigned char *data, 59 unsigned int actual_length) 60 { 61 } 62 63 static void f81232_read_int_callback(struct urb *urb) 64 { 65 struct usb_serial_port *port = urb->context; 66 unsigned char *data = urb->transfer_buffer; 67 unsigned int actual_length = urb->actual_length; 68 int status = urb->status; 69 int retval; 70 71 switch (status) { 72 case 0: 73 /* success */ 74 break; 75 case -ECONNRESET: 76 case -ENOENT: 77 case -ESHUTDOWN: 78 /* this urb is terminated, clean up */ 79 dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n", 80 __func__, status); 81 return; 82 default: 83 dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n", 84 __func__, status); 85 goto exit; 86 } 87 88 usb_serial_debug_data(debug, &port->dev, __func__, 89 urb->actual_length, urb->transfer_buffer); 90 91 f81232_update_line_status(port, data, actual_length); 92 93 exit: 94 retval = usb_submit_urb(urb, GFP_ATOMIC); 95 if (retval) 96 dev_err(&urb->dev->dev, 97 "%s - usb_submit_urb failed with result %d\n", 98 __func__, retval); 99 } 100 101 static void f81232_process_read_urb(struct urb *urb) 102 { 103 struct usb_serial_port *port = urb->context; 104 struct f81232_private *priv = usb_get_serial_port_data(port); 105 struct tty_struct *tty; 106 unsigned char *data = urb->transfer_buffer; 107 char tty_flag = TTY_NORMAL; 108 unsigned long flags; 109 u8 line_status; 110 int i; 111 112 /* update line status */ 113 spin_lock_irqsave(&priv->lock, flags); 114 line_status = priv->line_status; 115 priv->line_status &= ~UART_STATE_TRANSIENT_MASK; 116 spin_unlock_irqrestore(&priv->lock, flags); 117 wake_up_interruptible(&priv->delta_msr_wait); 118 119 if (!urb->actual_length) 120 return; 121 122 tty = tty_port_tty_get(&port->port); 123 if (!tty) 124 return; 125 126 /* break takes precedence over parity, */ 127 /* which takes precedence over framing errors */ 128 if (line_status & UART_BREAK_ERROR) 129 tty_flag = TTY_BREAK; 130 else if (line_status & UART_PARITY_ERROR) 131 tty_flag = TTY_PARITY; 132 else if (line_status & UART_FRAME_ERROR) 133 tty_flag = TTY_FRAME; 134 dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__, tty_flag); 135 136 /* overrun is special, not associated with a char */ 137 if (line_status & UART_OVERRUN_ERROR) 138 tty_insert_flip_char(tty, 0, TTY_OVERRUN); 139 140 if (port->port.console && port->sysrq) { 141 for (i = 0; i < urb->actual_length; ++i) 142 if (!usb_serial_handle_sysrq_char(port, data[i])) 143 tty_insert_flip_char(tty, data[i], tty_flag); 144 } else { 145 tty_insert_flip_string_fixed_flag(tty, data, tty_flag, 146 urb->actual_length); 147 } 148 149 tty_flip_buffer_push(tty); 150 tty_kref_put(tty); 151 } 152 153 static int set_control_lines(struct usb_device *dev, u8 value) 154 { 155 /* FIXME - Stubbed out for now */ 156 return 0; 157 } 158 159 static void f81232_break_ctl(struct tty_struct *tty, int break_state) 160 { 161 /* FIXME - Stubbed out for now */ 162 163 /* 164 * break_state = -1 to turn on break, and 0 to turn off break 165 * see drivers/char/tty_io.c to see it used. 166 * last_set_data_urb_value NEVER has the break bit set in it. 167 */ 168 } 169 170 static void f81232_set_termios(struct tty_struct *tty, 171 struct usb_serial_port *port, struct ktermios *old_termios) 172 { 173 /* FIXME - Stubbed out for now */ 174 175 /* Don't change anything if nothing has changed */ 176 if (!tty_termios_hw_change(&tty->termios, old_termios)) 177 return; 178 179 /* Do the real work here... */ 180 tty_termios_copy_hw(&tty->termios, old_termios); 181 } 182 183 static int f81232_tiocmget(struct tty_struct *tty) 184 { 185 /* FIXME - Stubbed out for now */ 186 return 0; 187 } 188 189 static int f81232_tiocmset(struct tty_struct *tty, 190 unsigned int set, unsigned int clear) 191 { 192 /* FIXME - Stubbed out for now */ 193 return 0; 194 } 195 196 static int f81232_open(struct tty_struct *tty, struct usb_serial_port *port) 197 { 198 struct ktermios tmp_termios; 199 int result; 200 201 /* Setup termios */ 202 if (tty) 203 f81232_set_termios(tty, port, &tmp_termios); 204 205 result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL); 206 if (result) { 207 dev_err(&port->dev, "%s - failed submitting interrupt urb," 208 " error %d\n", __func__, result); 209 return result; 210 } 211 212 result = usb_serial_generic_open(tty, port); 213 if (result) { 214 usb_kill_urb(port->interrupt_in_urb); 215 return result; 216 } 217 218 port->port.drain_delay = 256; 219 return 0; 220 } 221 222 static void f81232_close(struct usb_serial_port *port) 223 { 224 usb_serial_generic_close(port); 225 usb_kill_urb(port->interrupt_in_urb); 226 } 227 228 static void f81232_dtr_rts(struct usb_serial_port *port, int on) 229 { 230 struct f81232_private *priv = usb_get_serial_port_data(port); 231 unsigned long flags; 232 u8 control; 233 234 spin_lock_irqsave(&priv->lock, flags); 235 /* Change DTR and RTS */ 236 if (on) 237 priv->line_control |= (CONTROL_DTR | CONTROL_RTS); 238 else 239 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS); 240 control = priv->line_control; 241 spin_unlock_irqrestore(&priv->lock, flags); 242 set_control_lines(port->serial->dev, control); 243 } 244 245 static int f81232_carrier_raised(struct usb_serial_port *port) 246 { 247 struct f81232_private *priv = usb_get_serial_port_data(port); 248 if (priv->line_status & UART_DCD) 249 return 1; 250 return 0; 251 } 252 253 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg) 254 { 255 struct f81232_private *priv = usb_get_serial_port_data(port); 256 unsigned long flags; 257 unsigned int prevstatus; 258 unsigned int status; 259 unsigned int changed; 260 261 spin_lock_irqsave(&priv->lock, flags); 262 prevstatus = priv->line_status; 263 spin_unlock_irqrestore(&priv->lock, flags); 264 265 while (1) { 266 interruptible_sleep_on(&priv->delta_msr_wait); 267 /* see if a signal did it */ 268 if (signal_pending(current)) 269 return -ERESTARTSYS; 270 271 spin_lock_irqsave(&priv->lock, flags); 272 status = priv->line_status; 273 spin_unlock_irqrestore(&priv->lock, flags); 274 275 changed = prevstatus ^ status; 276 277 if (((arg & TIOCM_RNG) && (changed & UART_RING)) || 278 ((arg & TIOCM_DSR) && (changed & UART_DSR)) || 279 ((arg & TIOCM_CD) && (changed & UART_DCD)) || 280 ((arg & TIOCM_CTS) && (changed & UART_CTS))) { 281 return 0; 282 } 283 prevstatus = status; 284 } 285 /* NOTREACHED */ 286 return 0; 287 } 288 289 static int f81232_ioctl(struct tty_struct *tty, 290 unsigned int cmd, unsigned long arg) 291 { 292 struct serial_struct ser; 293 struct usb_serial_port *port = tty->driver_data; 294 295 dev_dbg(&port->dev, "%s (%d) cmd = 0x%04x\n", __func__, 296 port->number, cmd); 297 298 switch (cmd) { 299 case TIOCGSERIAL: 300 memset(&ser, 0, sizeof ser); 301 ser.type = PORT_16654; 302 ser.line = port->serial->minor; 303 ser.port = port->number; 304 ser.baud_base = 460800; 305 306 if (copy_to_user((void __user *)arg, &ser, sizeof ser)) 307 return -EFAULT; 308 309 return 0; 310 311 case TIOCMIWAIT: 312 dev_dbg(&port->dev, "%s (%d) TIOCMIWAIT\n", __func__, 313 port->number); 314 return wait_modem_info(port, arg); 315 default: 316 dev_dbg(&port->dev, "%s not supported = 0x%04x\n", 317 __func__, cmd); 318 break; 319 } 320 return -ENOIOCTLCMD; 321 } 322 323 static int f81232_startup(struct usb_serial *serial) 324 { 325 struct f81232_private *priv; 326 int i; 327 328 for (i = 0; i < serial->num_ports; ++i) { 329 priv = kzalloc(sizeof(struct f81232_private), GFP_KERNEL); 330 if (!priv) 331 goto cleanup; 332 spin_lock_init(&priv->lock); 333 init_waitqueue_head(&priv->delta_msr_wait); 334 usb_set_serial_port_data(serial->port[i], priv); 335 } 336 return 0; 337 338 cleanup: 339 for (--i; i >= 0; --i) { 340 priv = usb_get_serial_port_data(serial->port[i]); 341 kfree(priv); 342 usb_set_serial_port_data(serial->port[i], NULL); 343 } 344 return -ENOMEM; 345 } 346 347 static void f81232_release(struct usb_serial *serial) 348 { 349 int i; 350 struct f81232_private *priv; 351 352 for (i = 0; i < serial->num_ports; ++i) { 353 priv = usb_get_serial_port_data(serial->port[i]); 354 kfree(priv); 355 } 356 } 357 358 static struct usb_serial_driver f81232_device = { 359 .driver = { 360 .owner = THIS_MODULE, 361 .name = "f81232", 362 }, 363 .id_table = id_table, 364 .num_ports = 1, 365 .bulk_in_size = 256, 366 .bulk_out_size = 256, 367 .open = f81232_open, 368 .close = f81232_close, 369 .dtr_rts = f81232_dtr_rts, 370 .carrier_raised = f81232_carrier_raised, 371 .ioctl = f81232_ioctl, 372 .break_ctl = f81232_break_ctl, 373 .set_termios = f81232_set_termios, 374 .tiocmget = f81232_tiocmget, 375 .tiocmset = f81232_tiocmset, 376 .process_read_urb = f81232_process_read_urb, 377 .read_int_callback = f81232_read_int_callback, 378 .attach = f81232_startup, 379 .release = f81232_release, 380 }; 381 382 static struct usb_serial_driver * const serial_drivers[] = { 383 &f81232_device, 384 NULL, 385 }; 386 387 module_usb_serial_driver(serial_drivers, id_table); 388 389 MODULE_DESCRIPTION("Fintek F81232 USB to serial adaptor driver"); 390 MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org"); 391 MODULE_LICENSE("GPL v2"); 392 393 module_param(debug, bool, S_IRUGO | S_IWUSR); 394 MODULE_PARM_DESC(debug, "Debug enabled or not"); 395 396