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 const struct usb_device_id id_table[] = { 29 { USB_DEVICE(0x1934, 0x0706) }, 30 { } /* Terminating entry */ 31 }; 32 MODULE_DEVICE_TABLE(usb, id_table); 33 34 #define CONTROL_DTR 0x01 35 #define CONTROL_RTS 0x02 36 37 #define UART_STATE 0x08 38 #define UART_STATE_TRANSIENT_MASK 0x74 39 #define UART_DCD 0x01 40 #define UART_DSR 0x02 41 #define UART_BREAK_ERROR 0x04 42 #define UART_RING 0x08 43 #define UART_FRAME_ERROR 0x10 44 #define UART_PARITY_ERROR 0x20 45 #define UART_OVERRUN_ERROR 0x40 46 #define UART_CTS 0x80 47 48 struct f81232_private { 49 spinlock_t lock; 50 wait_queue_head_t delta_msr_wait; 51 u8 line_control; 52 u8 line_status; 53 }; 54 55 static void f81232_update_line_status(struct usb_serial_port *port, 56 unsigned char *data, 57 unsigned int actual_length) 58 { 59 } 60 61 static void f81232_read_int_callback(struct urb *urb) 62 { 63 struct usb_serial_port *port = urb->context; 64 unsigned char *data = urb->transfer_buffer; 65 unsigned int actual_length = urb->actual_length; 66 int status = urb->status; 67 int retval; 68 69 switch (status) { 70 case 0: 71 /* success */ 72 break; 73 case -ECONNRESET: 74 case -ENOENT: 75 case -ESHUTDOWN: 76 /* this urb is terminated, clean up */ 77 dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n", 78 __func__, status); 79 return; 80 default: 81 dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n", 82 __func__, status); 83 goto exit; 84 } 85 86 usb_serial_debug_data(&port->dev, __func__, 87 urb->actual_length, urb->transfer_buffer); 88 89 f81232_update_line_status(port, data, actual_length); 90 91 exit: 92 retval = usb_submit_urb(urb, GFP_ATOMIC); 93 if (retval) 94 dev_err(&urb->dev->dev, 95 "%s - usb_submit_urb failed with result %d\n", 96 __func__, retval); 97 } 98 99 static void f81232_process_read_urb(struct urb *urb) 100 { 101 struct usb_serial_port *port = urb->context; 102 struct f81232_private *priv = usb_get_serial_port_data(port); 103 struct tty_struct *tty; 104 unsigned char *data = urb->transfer_buffer; 105 char tty_flag = TTY_NORMAL; 106 unsigned long flags; 107 u8 line_status; 108 int i; 109 110 /* update line status */ 111 spin_lock_irqsave(&priv->lock, flags); 112 line_status = priv->line_status; 113 priv->line_status &= ~UART_STATE_TRANSIENT_MASK; 114 spin_unlock_irqrestore(&priv->lock, flags); 115 wake_up_interruptible(&priv->delta_msr_wait); 116 117 if (!urb->actual_length) 118 return; 119 120 tty = tty_port_tty_get(&port->port); 121 if (!tty) 122 return; 123 124 /* break takes precedence over parity, */ 125 /* which takes precedence over framing errors */ 126 if (line_status & UART_BREAK_ERROR) 127 tty_flag = TTY_BREAK; 128 else if (line_status & UART_PARITY_ERROR) 129 tty_flag = TTY_PARITY; 130 else if (line_status & UART_FRAME_ERROR) 131 tty_flag = TTY_FRAME; 132 dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__, tty_flag); 133 134 /* overrun is special, not associated with a char */ 135 if (line_status & UART_OVERRUN_ERROR) 136 tty_insert_flip_char(tty, 0, TTY_OVERRUN); 137 138 if (port->port.console && port->sysrq) { 139 for (i = 0; i < urb->actual_length; ++i) 140 if (!usb_serial_handle_sysrq_char(port, data[i])) 141 tty_insert_flip_char(tty, data[i], tty_flag); 142 } else { 143 tty_insert_flip_string_fixed_flag(tty, data, tty_flag, 144 urb->actual_length); 145 } 146 147 tty_flip_buffer_push(tty); 148 tty_kref_put(tty); 149 } 150 151 static int set_control_lines(struct usb_device *dev, u8 value) 152 { 153 /* FIXME - Stubbed out for now */ 154 return 0; 155 } 156 157 static void f81232_break_ctl(struct tty_struct *tty, int break_state) 158 { 159 /* FIXME - Stubbed out for now */ 160 161 /* 162 * break_state = -1 to turn on break, and 0 to turn off break 163 * see drivers/char/tty_io.c to see it used. 164 * last_set_data_urb_value NEVER has the break bit set in it. 165 */ 166 } 167 168 static void f81232_set_termios(struct tty_struct *tty, 169 struct usb_serial_port *port, struct ktermios *old_termios) 170 { 171 /* FIXME - Stubbed out for now */ 172 173 /* Don't change anything if nothing has changed */ 174 if (!tty_termios_hw_change(&tty->termios, old_termios)) 175 return; 176 177 /* Do the real work here... */ 178 tty_termios_copy_hw(&tty->termios, old_termios); 179 } 180 181 static int f81232_tiocmget(struct tty_struct *tty) 182 { 183 /* FIXME - Stubbed out for now */ 184 return 0; 185 } 186 187 static int f81232_tiocmset(struct tty_struct *tty, 188 unsigned int set, unsigned int clear) 189 { 190 /* FIXME - Stubbed out for now */ 191 return 0; 192 } 193 194 static int f81232_open(struct tty_struct *tty, struct usb_serial_port *port) 195 { 196 struct ktermios tmp_termios; 197 int result; 198 199 /* Setup termios */ 200 if (tty) 201 f81232_set_termios(tty, port, &tmp_termios); 202 203 result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL); 204 if (result) { 205 dev_err(&port->dev, "%s - failed submitting interrupt urb," 206 " error %d\n", __func__, result); 207 return result; 208 } 209 210 result = usb_serial_generic_open(tty, port); 211 if (result) { 212 usb_kill_urb(port->interrupt_in_urb); 213 return result; 214 } 215 216 port->port.drain_delay = 256; 217 return 0; 218 } 219 220 static void f81232_close(struct usb_serial_port *port) 221 { 222 usb_serial_generic_close(port); 223 usb_kill_urb(port->interrupt_in_urb); 224 } 225 226 static void f81232_dtr_rts(struct usb_serial_port *port, int on) 227 { 228 struct f81232_private *priv = usb_get_serial_port_data(port); 229 unsigned long flags; 230 u8 control; 231 232 spin_lock_irqsave(&priv->lock, flags); 233 /* Change DTR and RTS */ 234 if (on) 235 priv->line_control |= (CONTROL_DTR | CONTROL_RTS); 236 else 237 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS); 238 control = priv->line_control; 239 spin_unlock_irqrestore(&priv->lock, flags); 240 set_control_lines(port->serial->dev, control); 241 } 242 243 static int f81232_carrier_raised(struct usb_serial_port *port) 244 { 245 struct f81232_private *priv = usb_get_serial_port_data(port); 246 if (priv->line_status & UART_DCD) 247 return 1; 248 return 0; 249 } 250 251 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg) 252 { 253 struct f81232_private *priv = usb_get_serial_port_data(port); 254 unsigned long flags; 255 unsigned int prevstatus; 256 unsigned int status; 257 unsigned int changed; 258 259 spin_lock_irqsave(&priv->lock, flags); 260 prevstatus = priv->line_status; 261 spin_unlock_irqrestore(&priv->lock, flags); 262 263 while (1) { 264 interruptible_sleep_on(&priv->delta_msr_wait); 265 /* see if a signal did it */ 266 if (signal_pending(current)) 267 return -ERESTARTSYS; 268 269 spin_lock_irqsave(&priv->lock, flags); 270 status = priv->line_status; 271 spin_unlock_irqrestore(&priv->lock, flags); 272 273 changed = prevstatus ^ status; 274 275 if (((arg & TIOCM_RNG) && (changed & UART_RING)) || 276 ((arg & TIOCM_DSR) && (changed & UART_DSR)) || 277 ((arg & TIOCM_CD) && (changed & UART_DCD)) || 278 ((arg & TIOCM_CTS) && (changed & UART_CTS))) { 279 return 0; 280 } 281 prevstatus = status; 282 } 283 /* NOTREACHED */ 284 return 0; 285 } 286 287 static int f81232_ioctl(struct tty_struct *tty, 288 unsigned int cmd, unsigned long arg) 289 { 290 struct serial_struct ser; 291 struct usb_serial_port *port = tty->driver_data; 292 293 dev_dbg(&port->dev, "%s (%d) cmd = 0x%04x\n", __func__, 294 port->number, cmd); 295 296 switch (cmd) { 297 case TIOCGSERIAL: 298 memset(&ser, 0, sizeof ser); 299 ser.type = PORT_16654; 300 ser.line = port->serial->minor; 301 ser.port = port->number; 302 ser.baud_base = 460800; 303 304 if (copy_to_user((void __user *)arg, &ser, sizeof ser)) 305 return -EFAULT; 306 307 return 0; 308 309 case TIOCMIWAIT: 310 dev_dbg(&port->dev, "%s (%d) TIOCMIWAIT\n", __func__, 311 port->number); 312 return wait_modem_info(port, arg); 313 default: 314 dev_dbg(&port->dev, "%s not supported = 0x%04x\n", 315 __func__, cmd); 316 break; 317 } 318 return -ENOIOCTLCMD; 319 } 320 321 static int f81232_port_probe(struct usb_serial_port *port) 322 { 323 struct f81232_private *priv; 324 325 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 326 if (!priv) 327 return -ENOMEM; 328 329 spin_lock_init(&priv->lock); 330 init_waitqueue_head(&priv->delta_msr_wait); 331 332 usb_set_serial_port_data(port, priv); 333 334 return 0; 335 } 336 337 static int f81232_port_remove(struct usb_serial_port *port) 338 { 339 struct f81232_private *priv; 340 341 priv = usb_get_serial_port_data(port); 342 kfree(priv); 343 344 return 0; 345 } 346 347 static struct usb_serial_driver f81232_device = { 348 .driver = { 349 .owner = THIS_MODULE, 350 .name = "f81232", 351 }, 352 .id_table = id_table, 353 .num_ports = 1, 354 .bulk_in_size = 256, 355 .bulk_out_size = 256, 356 .open = f81232_open, 357 .close = f81232_close, 358 .dtr_rts = f81232_dtr_rts, 359 .carrier_raised = f81232_carrier_raised, 360 .ioctl = f81232_ioctl, 361 .break_ctl = f81232_break_ctl, 362 .set_termios = f81232_set_termios, 363 .tiocmget = f81232_tiocmget, 364 .tiocmset = f81232_tiocmset, 365 .process_read_urb = f81232_process_read_urb, 366 .read_int_callback = f81232_read_int_callback, 367 .port_probe = f81232_port_probe, 368 .port_remove = f81232_port_remove, 369 }; 370 371 static struct usb_serial_driver * const serial_drivers[] = { 372 &f81232_device, 373 NULL, 374 }; 375 376 module_usb_serial_driver(serial_drivers, id_table); 377 378 MODULE_DESCRIPTION("Fintek F81232 USB to serial adaptor driver"); 379 MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org"); 380 MODULE_LICENSE("GPL v2"); 381