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 port->port.drain_delay = 256; 211 return 0; 212 } 213 214 static void f81232_close(struct usb_serial_port *port) 215 { 216 usb_serial_generic_close(port); 217 usb_kill_urb(port->interrupt_in_urb); 218 } 219 220 static void f81232_dtr_rts(struct usb_serial_port *port, int on) 221 { 222 struct f81232_private *priv = usb_get_serial_port_data(port); 223 unsigned long flags; 224 u8 control; 225 226 spin_lock_irqsave(&priv->lock, flags); 227 /* Change DTR and RTS */ 228 if (on) 229 priv->line_control |= (CONTROL_DTR | CONTROL_RTS); 230 else 231 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS); 232 control = priv->line_control; 233 spin_unlock_irqrestore(&priv->lock, flags); 234 set_control_lines(port->serial->dev, control); 235 } 236 237 static int f81232_carrier_raised(struct usb_serial_port *port) 238 { 239 struct f81232_private *priv = usb_get_serial_port_data(port); 240 if (priv->line_status & UART_DCD) 241 return 1; 242 return 0; 243 } 244 245 static int f81232_tiocmiwait(struct tty_struct *tty, unsigned long arg) 246 { 247 struct usb_serial_port *port = tty->driver_data; 248 struct f81232_private *priv = usb_get_serial_port_data(port); 249 unsigned long flags; 250 unsigned int prevstatus; 251 unsigned int status; 252 unsigned int changed; 253 254 spin_lock_irqsave(&priv->lock, flags); 255 prevstatus = priv->line_status; 256 spin_unlock_irqrestore(&priv->lock, flags); 257 258 while (1) { 259 interruptible_sleep_on(&port->port.delta_msr_wait); 260 /* see if a signal did it */ 261 if (signal_pending(current)) 262 return -ERESTARTSYS; 263 264 if (port->serial->disconnected) 265 return -EIO; 266 267 spin_lock_irqsave(&priv->lock, flags); 268 status = priv->line_status; 269 spin_unlock_irqrestore(&priv->lock, flags); 270 271 changed = prevstatus ^ status; 272 273 if (((arg & TIOCM_RNG) && (changed & UART_RING)) || 274 ((arg & TIOCM_DSR) && (changed & UART_DSR)) || 275 ((arg & TIOCM_CD) && (changed & UART_DCD)) || 276 ((arg & TIOCM_CTS) && (changed & UART_CTS))) { 277 return 0; 278 } 279 prevstatus = status; 280 } 281 /* NOTREACHED */ 282 return 0; 283 } 284 285 static int f81232_ioctl(struct tty_struct *tty, 286 unsigned int cmd, unsigned long arg) 287 { 288 struct serial_struct ser; 289 struct usb_serial_port *port = tty->driver_data; 290 291 dev_dbg(&port->dev, "%s cmd = 0x%04x\n", __func__, cmd); 292 293 switch (cmd) { 294 case TIOCGSERIAL: 295 memset(&ser, 0, sizeof ser); 296 ser.type = PORT_16654; 297 ser.line = port->minor; 298 ser.port = port->port_number; 299 ser.baud_base = 460800; 300 301 if (copy_to_user((void __user *)arg, &ser, sizeof ser)) 302 return -EFAULT; 303 304 return 0; 305 default: 306 dev_dbg(&port->dev, "%s not supported = 0x%04x\n", 307 __func__, cmd); 308 break; 309 } 310 return -ENOIOCTLCMD; 311 } 312 313 static int f81232_port_probe(struct usb_serial_port *port) 314 { 315 struct f81232_private *priv; 316 317 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 318 if (!priv) 319 return -ENOMEM; 320 321 spin_lock_init(&priv->lock); 322 323 usb_set_serial_port_data(port, priv); 324 325 return 0; 326 } 327 328 static int f81232_port_remove(struct usb_serial_port *port) 329 { 330 struct f81232_private *priv; 331 332 priv = usb_get_serial_port_data(port); 333 kfree(priv); 334 335 return 0; 336 } 337 338 static struct usb_serial_driver f81232_device = { 339 .driver = { 340 .owner = THIS_MODULE, 341 .name = "f81232", 342 }, 343 .id_table = id_table, 344 .num_ports = 1, 345 .bulk_in_size = 256, 346 .bulk_out_size = 256, 347 .open = f81232_open, 348 .close = f81232_close, 349 .dtr_rts = f81232_dtr_rts, 350 .carrier_raised = f81232_carrier_raised, 351 .ioctl = f81232_ioctl, 352 .break_ctl = f81232_break_ctl, 353 .set_termios = f81232_set_termios, 354 .tiocmget = f81232_tiocmget, 355 .tiocmset = f81232_tiocmset, 356 .tiocmiwait = f81232_tiocmiwait, 357 .process_read_urb = f81232_process_read_urb, 358 .read_int_callback = f81232_read_int_callback, 359 .port_probe = f81232_port_probe, 360 .port_remove = f81232_port_remove, 361 }; 362 363 static struct usb_serial_driver * const serial_drivers[] = { 364 &f81232_device, 365 NULL, 366 }; 367 368 module_usb_serial_driver(serial_drivers, id_table); 369 370 MODULE_DESCRIPTION("Fintek F81232 USB to serial adaptor driver"); 371 MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org"); 372 MODULE_LICENSE("GPL v2"); 373