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 u8 line_control; 51 u8 line_status; 52 }; 53 54 static void f81232_update_line_status(struct usb_serial_port *port, 55 unsigned char *data, 56 unsigned int actual_length) 57 { 58 } 59 60 static void f81232_read_int_callback(struct urb *urb) 61 { 62 struct usb_serial_port *port = urb->context; 63 unsigned char *data = urb->transfer_buffer; 64 unsigned int actual_length = urb->actual_length; 65 int status = urb->status; 66 int retval; 67 68 switch (status) { 69 case 0: 70 /* success */ 71 break; 72 case -ECONNRESET: 73 case -ENOENT: 74 case -ESHUTDOWN: 75 /* this urb is terminated, clean up */ 76 dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n", 77 __func__, status); 78 return; 79 default: 80 dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n", 81 __func__, status); 82 goto exit; 83 } 84 85 usb_serial_debug_data(&port->dev, __func__, 86 urb->actual_length, urb->transfer_buffer); 87 88 f81232_update_line_status(port, data, actual_length); 89 90 exit: 91 retval = usb_submit_urb(urb, GFP_ATOMIC); 92 if (retval) 93 dev_err(&urb->dev->dev, 94 "%s - usb_submit_urb failed with result %d\n", 95 __func__, retval); 96 } 97 98 static void f81232_process_read_urb(struct urb *urb) 99 { 100 struct usb_serial_port *port = urb->context; 101 struct f81232_private *priv = usb_get_serial_port_data(port); 102 unsigned char *data = urb->transfer_buffer; 103 char tty_flag = TTY_NORMAL; 104 unsigned long flags; 105 u8 line_status; 106 int i; 107 108 /* update line status */ 109 spin_lock_irqsave(&priv->lock, flags); 110 line_status = priv->line_status; 111 priv->line_status &= ~UART_STATE_TRANSIENT_MASK; 112 spin_unlock_irqrestore(&priv->lock, flags); 113 wake_up_interruptible(&port->port.delta_msr_wait); 114 115 if (!urb->actual_length) 116 return; 117 118 /* break takes precedence over parity, */ 119 /* which takes precedence over framing errors */ 120 if (line_status & UART_BREAK_ERROR) 121 tty_flag = TTY_BREAK; 122 else if (line_status & UART_PARITY_ERROR) 123 tty_flag = TTY_PARITY; 124 else if (line_status & UART_FRAME_ERROR) 125 tty_flag = TTY_FRAME; 126 dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__, tty_flag); 127 128 /* overrun is special, not associated with a char */ 129 if (line_status & UART_OVERRUN_ERROR) 130 tty_insert_flip_char(&port->port, 0, TTY_OVERRUN); 131 132 if (port->port.console && port->sysrq) { 133 for (i = 0; i < urb->actual_length; ++i) 134 if (!usb_serial_handle_sysrq_char(port, data[i])) 135 tty_insert_flip_char(&port->port, data[i], 136 tty_flag); 137 } else { 138 tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag, 139 urb->actual_length); 140 } 141 142 tty_flip_buffer_push(&port->port); 143 } 144 145 static int set_control_lines(struct usb_device *dev, u8 value) 146 { 147 /* FIXME - Stubbed out for now */ 148 return 0; 149 } 150 151 static void f81232_break_ctl(struct tty_struct *tty, int break_state) 152 { 153 /* FIXME - Stubbed out for now */ 154 155 /* 156 * break_state = -1 to turn on break, and 0 to turn off break 157 * see drivers/char/tty_io.c to see it used. 158 * last_set_data_urb_value NEVER has the break bit set in it. 159 */ 160 } 161 162 static void f81232_set_termios(struct tty_struct *tty, 163 struct usb_serial_port *port, struct ktermios *old_termios) 164 { 165 /* FIXME - Stubbed out for now */ 166 167 /* Don't change anything if nothing has changed */ 168 if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios)) 169 return; 170 171 /* Do the real work here... */ 172 if (old_termios) 173 tty_termios_copy_hw(&tty->termios, old_termios); 174 } 175 176 static int f81232_tiocmget(struct tty_struct *tty) 177 { 178 /* FIXME - Stubbed out for now */ 179 return 0; 180 } 181 182 static int f81232_tiocmset(struct tty_struct *tty, 183 unsigned int set, unsigned int clear) 184 { 185 /* FIXME - Stubbed out for now */ 186 return 0; 187 } 188 189 static int f81232_open(struct tty_struct *tty, struct usb_serial_port *port) 190 { 191 int result; 192 193 /* Setup termios */ 194 if (tty) 195 f81232_set_termios(tty, port, NULL); 196 197 result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL); 198 if (result) { 199 dev_err(&port->dev, "%s - failed submitting interrupt urb," 200 " error %d\n", __func__, result); 201 return result; 202 } 203 204 result = usb_serial_generic_open(tty, port); 205 if (result) { 206 usb_kill_urb(port->interrupt_in_urb); 207 return result; 208 } 209 210 return 0; 211 } 212 213 static void f81232_close(struct usb_serial_port *port) 214 { 215 usb_serial_generic_close(port); 216 usb_kill_urb(port->interrupt_in_urb); 217 } 218 219 static void f81232_dtr_rts(struct usb_serial_port *port, int on) 220 { 221 struct f81232_private *priv = usb_get_serial_port_data(port); 222 unsigned long flags; 223 u8 control; 224 225 spin_lock_irqsave(&priv->lock, flags); 226 /* Change DTR and RTS */ 227 if (on) 228 priv->line_control |= (CONTROL_DTR | CONTROL_RTS); 229 else 230 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS); 231 control = priv->line_control; 232 spin_unlock_irqrestore(&priv->lock, flags); 233 set_control_lines(port->serial->dev, control); 234 } 235 236 static int f81232_carrier_raised(struct usb_serial_port *port) 237 { 238 struct f81232_private *priv = usb_get_serial_port_data(port); 239 if (priv->line_status & UART_DCD) 240 return 1; 241 return 0; 242 } 243 244 static int f81232_tiocmiwait(struct tty_struct *tty, unsigned long arg) 245 { 246 struct usb_serial_port *port = tty->driver_data; 247 struct f81232_private *priv = usb_get_serial_port_data(port); 248 unsigned long flags; 249 unsigned int prevstatus; 250 unsigned int status; 251 unsigned int changed; 252 253 spin_lock_irqsave(&priv->lock, flags); 254 prevstatus = priv->line_status; 255 spin_unlock_irqrestore(&priv->lock, flags); 256 257 while (1) { 258 interruptible_sleep_on(&port->port.delta_msr_wait); 259 /* see if a signal did it */ 260 if (signal_pending(current)) 261 return -ERESTARTSYS; 262 263 if (port->serial->disconnected) 264 return -EIO; 265 266 spin_lock_irqsave(&priv->lock, flags); 267 status = priv->line_status; 268 spin_unlock_irqrestore(&priv->lock, flags); 269 270 changed = prevstatus ^ status; 271 272 if (((arg & TIOCM_RNG) && (changed & UART_RING)) || 273 ((arg & TIOCM_DSR) && (changed & UART_DSR)) || 274 ((arg & TIOCM_CD) && (changed & UART_DCD)) || 275 ((arg & TIOCM_CTS) && (changed & UART_CTS))) { 276 return 0; 277 } 278 prevstatus = status; 279 } 280 /* NOTREACHED */ 281 return 0; 282 } 283 284 static int f81232_ioctl(struct tty_struct *tty, 285 unsigned int cmd, unsigned long arg) 286 { 287 struct serial_struct ser; 288 struct usb_serial_port *port = tty->driver_data; 289 290 dev_dbg(&port->dev, "%s cmd = 0x%04x\n", __func__, cmd); 291 292 switch (cmd) { 293 case TIOCGSERIAL: 294 memset(&ser, 0, sizeof ser); 295 ser.type = PORT_16654; 296 ser.line = port->minor; 297 ser.port = port->port_number; 298 ser.baud_base = 460800; 299 300 if (copy_to_user((void __user *)arg, &ser, sizeof ser)) 301 return -EFAULT; 302 303 return 0; 304 default: 305 dev_dbg(&port->dev, "%s not supported = 0x%04x\n", 306 __func__, cmd); 307 break; 308 } 309 return -ENOIOCTLCMD; 310 } 311 312 static int f81232_port_probe(struct usb_serial_port *port) 313 { 314 struct f81232_private *priv; 315 316 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 317 if (!priv) 318 return -ENOMEM; 319 320 spin_lock_init(&priv->lock); 321 322 usb_set_serial_port_data(port, priv); 323 324 port->port.drain_delay = 256; 325 326 return 0; 327 } 328 329 static int f81232_port_remove(struct usb_serial_port *port) 330 { 331 struct f81232_private *priv; 332 333 priv = usb_get_serial_port_data(port); 334 kfree(priv); 335 336 return 0; 337 } 338 339 static struct usb_serial_driver f81232_device = { 340 .driver = { 341 .owner = THIS_MODULE, 342 .name = "f81232", 343 }, 344 .id_table = id_table, 345 .num_ports = 1, 346 .bulk_in_size = 256, 347 .bulk_out_size = 256, 348 .open = f81232_open, 349 .close = f81232_close, 350 .dtr_rts = f81232_dtr_rts, 351 .carrier_raised = f81232_carrier_raised, 352 .ioctl = f81232_ioctl, 353 .break_ctl = f81232_break_ctl, 354 .set_termios = f81232_set_termios, 355 .tiocmget = f81232_tiocmget, 356 .tiocmset = f81232_tiocmset, 357 .tiocmiwait = f81232_tiocmiwait, 358 .process_read_urb = f81232_process_read_urb, 359 .read_int_callback = f81232_read_int_callback, 360 .port_probe = f81232_port_probe, 361 .port_remove = f81232_port_remove, 362 }; 363 364 static struct usb_serial_driver * const serial_drivers[] = { 365 &f81232_device, 366 NULL, 367 }; 368 369 module_usb_serial_driver(serial_drivers, id_table); 370 371 MODULE_DESCRIPTION("Fintek F81232 USB to serial adaptor driver"); 372 MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org"); 373 MODULE_LICENSE("GPL v2"); 374