Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | ** mux.c: |
| 3 | ** serial driver for the Mux console found in some PA-RISC servers. |
| 4 | ** |
| 5 | ** (c) Copyright 2002 Ryan Bradetich |
| 6 | ** (c) Copyright 2002 Hewlett-Packard Company |
| 7 | ** |
| 8 | ** This program is free software; you can redistribute it and/or modify |
| 9 | ** it under the terms of the GNU General Public License as published by |
| 10 | ** the Free Software Foundation; either version 2 of the License, or |
| 11 | ** (at your option) any later version. |
| 12 | ** |
| 13 | ** This Driver currently only supports the console (port 0) on the MUX. |
| 14 | ** Additional work will be needed on this driver to enable the full |
| 15 | ** functionality of the MUX. |
| 16 | ** |
| 17 | */ |
| 18 | |
| 19 | #include <linux/config.h> |
| 20 | #include <linux/module.h> |
| 21 | #include <linux/tty.h> |
| 22 | #include <linux/ioport.h> |
| 23 | #include <linux/init.h> |
| 24 | #include <linux/serial.h> |
| 25 | #include <linux/console.h> |
| 26 | #include <linux/slab.h> |
| 27 | #include <linux/delay.h> /* for udelay */ |
| 28 | #include <linux/device.h> |
| 29 | #include <asm/io.h> |
Matthew Wilcox | ae8c75c | 2005-10-21 22:58:03 -0400 | [diff] [blame] | 30 | #include <asm/irq.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | #include <asm/parisc-device.h> |
| 32 | |
| 33 | #ifdef CONFIG_MAGIC_SYSRQ |
| 34 | #include <linux/sysrq.h> |
| 35 | #define SUPPORT_SYSRQ |
| 36 | #endif |
| 37 | |
| 38 | #include <linux/serial_core.h> |
| 39 | |
| 40 | #define MUX_OFFSET 0x800 |
| 41 | #define MUX_LINE_OFFSET 0x80 |
| 42 | |
| 43 | #define MUX_FIFO_SIZE 255 |
| 44 | #define MUX_POLL_DELAY (30 * HZ / 1000) |
| 45 | |
| 46 | #define IO_DATA_REG_OFFSET 0x3c |
| 47 | #define IO_DCOUNT_REG_OFFSET 0x40 |
| 48 | |
| 49 | #define MUX_EOFIFO(status) ((status & 0xF000) == 0xF000) |
| 50 | #define MUX_STATUS(status) ((status & 0xF000) == 0x8000) |
| 51 | #define MUX_BREAK(status) ((status & 0xF000) == 0x2000) |
| 52 | |
| 53 | #define MUX_NR 256 |
| 54 | static unsigned int port_cnt = 0; |
| 55 | static struct uart_port mux_ports[MUX_NR]; |
| 56 | |
| 57 | static struct uart_driver mux_driver = { |
| 58 | .owner = THIS_MODULE, |
| 59 | .driver_name = "ttyB", |
| 60 | .dev_name = "ttyB", |
| 61 | .major = MUX_MAJOR, |
| 62 | .minor = 0, |
| 63 | .nr = MUX_NR, |
| 64 | }; |
| 65 | |
| 66 | static struct timer_list mux_timer; |
| 67 | |
Ryan Bradetich | 92495c0 | 2005-11-17 16:36:52 -0500 | [diff] [blame] | 68 | #define UART_PUT_CHAR(p, c) __raw_writel((c), (p)->membase + IO_DATA_REG_OFFSET) |
| 69 | #define UART_GET_FIFO_CNT(p) __raw_readl((p)->membase + IO_DCOUNT_REG_OFFSET) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | #define GET_MUX_PORTS(iodc_data) ((((iodc_data)[4] & 0xf0) >> 4) * 8) + 8 |
| 71 | |
| 72 | /** |
| 73 | * mux_tx_empty - Check if the transmitter fifo is empty. |
| 74 | * @port: Ptr to the uart_port. |
| 75 | * |
| 76 | * This function test if the transmitter fifo for the port |
| 77 | * described by 'port' is empty. If it is empty, this function |
| 78 | * should return TIOCSER_TEMT, otherwise return 0. |
| 79 | */ |
| 80 | static unsigned int mux_tx_empty(struct uart_port *port) |
| 81 | { |
Ryan Bradetich | 92495c0 | 2005-11-17 16:36:52 -0500 | [diff] [blame] | 82 | return UART_GET_FIFO_CNT(port) ? 0 : TIOCSER_TEMT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 83 | } |
| 84 | |
| 85 | /** |
| 86 | * mux_set_mctrl - Set the current state of the modem control inputs. |
| 87 | * @ports: Ptr to the uart_port. |
| 88 | * @mctrl: Modem control bits. |
| 89 | * |
| 90 | * The Serial MUX does not support CTS, DCD or DSR so this function |
| 91 | * is ignored. |
| 92 | */ |
| 93 | static void mux_set_mctrl(struct uart_port *port, unsigned int mctrl) |
| 94 | { |
| 95 | } |
| 96 | |
| 97 | /** |
| 98 | * mux_get_mctrl - Returns the current state of modem control inputs. |
| 99 | * @port: Ptr to the uart_port. |
| 100 | * |
| 101 | * The Serial MUX does not support CTS, DCD or DSR so these lines are |
| 102 | * treated as permanently active. |
| 103 | */ |
| 104 | static unsigned int mux_get_mctrl(struct uart_port *port) |
| 105 | { |
| 106 | return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS; |
| 107 | } |
| 108 | |
| 109 | /** |
| 110 | * mux_stop_tx - Stop transmitting characters. |
| 111 | * @port: Ptr to the uart_port. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | * |
| 113 | * The Serial MUX does not support this function. |
| 114 | */ |
Russell King | b129a8c | 2005-08-31 10:12:14 +0100 | [diff] [blame] | 115 | static void mux_stop_tx(struct uart_port *port) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | { |
| 117 | } |
| 118 | |
| 119 | /** |
| 120 | * mux_start_tx - Start transmitting characters. |
| 121 | * @port: Ptr to the uart_port. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | * |
| 123 | * The Serial Mux does not support this function. |
| 124 | */ |
Russell King | b129a8c | 2005-08-31 10:12:14 +0100 | [diff] [blame] | 125 | static void mux_start_tx(struct uart_port *port) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | { |
| 127 | } |
| 128 | |
| 129 | /** |
| 130 | * mux_stop_rx - Stop receiving characters. |
| 131 | * @port: Ptr to the uart_port. |
| 132 | * |
| 133 | * The Serial Mux does not support this function. |
| 134 | */ |
| 135 | static void mux_stop_rx(struct uart_port *port) |
| 136 | { |
| 137 | } |
| 138 | |
| 139 | /** |
| 140 | * mux_enable_ms - Enable modum status interrupts. |
| 141 | * @port: Ptr to the uart_port. |
| 142 | * |
| 143 | * The Serial Mux does not support this function. |
| 144 | */ |
| 145 | static void mux_enable_ms(struct uart_port *port) |
| 146 | { |
| 147 | } |
| 148 | |
| 149 | /** |
| 150 | * mux_break_ctl - Control the transmitssion of a break signal. |
| 151 | * @port: Ptr to the uart_port. |
| 152 | * @break_state: Raise/Lower the break signal. |
| 153 | * |
| 154 | * The Serial Mux does not support this function. |
| 155 | */ |
| 156 | static void mux_break_ctl(struct uart_port *port, int break_state) |
| 157 | { |
| 158 | } |
| 159 | |
| 160 | /** |
| 161 | * mux_write - Write chars to the mux fifo. |
| 162 | * @port: Ptr to the uart_port. |
| 163 | * |
| 164 | * This function writes all the data from the uart buffer to |
| 165 | * the mux fifo. |
| 166 | */ |
| 167 | static void mux_write(struct uart_port *port) |
| 168 | { |
| 169 | int count; |
| 170 | struct circ_buf *xmit = &port->info->xmit; |
| 171 | |
| 172 | if(port->x_char) { |
| 173 | UART_PUT_CHAR(port, port->x_char); |
| 174 | port->icount.tx++; |
| 175 | port->x_char = 0; |
| 176 | return; |
| 177 | } |
| 178 | |
| 179 | if(uart_circ_empty(xmit) || uart_tx_stopped(port)) { |
Russell King | b129a8c | 2005-08-31 10:12:14 +0100 | [diff] [blame] | 180 | mux_stop_tx(port); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 181 | return; |
| 182 | } |
| 183 | |
| 184 | count = (port->fifosize) - UART_GET_FIFO_CNT(port); |
| 185 | do { |
| 186 | UART_PUT_CHAR(port, xmit->buf[xmit->tail]); |
| 187 | xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); |
| 188 | port->icount.tx++; |
| 189 | if(uart_circ_empty(xmit)) |
| 190 | break; |
| 191 | |
| 192 | } while(--count > 0); |
| 193 | |
| 194 | while(UART_GET_FIFO_CNT(port)) |
| 195 | udelay(1); |
| 196 | |
| 197 | if(uart_circ_chars_pending(xmit) < WAKEUP_CHARS) |
| 198 | uart_write_wakeup(port); |
| 199 | |
| 200 | if (uart_circ_empty(xmit)) |
Russell King | b129a8c | 2005-08-31 10:12:14 +0100 | [diff] [blame] | 201 | mux_stop_tx(port); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 202 | } |
| 203 | |
| 204 | /** |
| 205 | * mux_read - Read chars from the mux fifo. |
| 206 | * @port: Ptr to the uart_port. |
| 207 | * |
| 208 | * This reads all available data from the mux's fifo and pushes |
| 209 | * the data to the tty layer. |
| 210 | */ |
| 211 | static void mux_read(struct uart_port *port) |
| 212 | { |
| 213 | int data; |
| 214 | struct tty_struct *tty = port->info->tty; |
| 215 | __u32 start_count = port->icount.rx; |
| 216 | |
| 217 | while(1) { |
Ryan Bradetich | 92495c0 | 2005-11-17 16:36:52 -0500 | [diff] [blame] | 218 | data = __raw_readl(port->membase + IO_DATA_REG_OFFSET); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | |
| 220 | if (MUX_STATUS(data)) |
| 221 | continue; |
| 222 | |
| 223 | if (MUX_EOFIFO(data)) |
| 224 | break; |
| 225 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | port->icount.rx++; |
| 227 | |
| 228 | if (MUX_BREAK(data)) { |
| 229 | port->icount.brk++; |
| 230 | if(uart_handle_break(port)) |
| 231 | continue; |
| 232 | } |
| 233 | |
| 234 | if (uart_handle_sysrq_char(port, data & 0xffu, NULL)) |
| 235 | continue; |
| 236 | |
Alan Cox | 33f0f88 | 2006-01-09 20:54:13 -0800 | [diff] [blame] | 237 | tty_insert_flip_char(tty, data & 0xFF, TTY_NORMAL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | } |
| 239 | |
| 240 | if (start_count != port->icount.rx) { |
| 241 | tty_flip_buffer_push(tty); |
| 242 | } |
| 243 | } |
| 244 | |
| 245 | /** |
| 246 | * mux_startup - Initialize the port. |
| 247 | * @port: Ptr to the uart_port. |
| 248 | * |
| 249 | * Grab any resources needed for this port and start the |
| 250 | * mux timer. |
| 251 | */ |
| 252 | static int mux_startup(struct uart_port *port) |
| 253 | { |
| 254 | mod_timer(&mux_timer, jiffies + MUX_POLL_DELAY); |
| 255 | return 0; |
| 256 | } |
| 257 | |
| 258 | /** |
| 259 | * mux_shutdown - Disable the port. |
| 260 | * @port: Ptr to the uart_port. |
| 261 | * |
| 262 | * Release any resources needed for the port. |
| 263 | */ |
| 264 | static void mux_shutdown(struct uart_port *port) |
| 265 | { |
| 266 | } |
| 267 | |
| 268 | /** |
| 269 | * mux_set_termios - Chane port parameters. |
| 270 | * @port: Ptr to the uart_port. |
| 271 | * @termios: new termios settings. |
| 272 | * @old: old termios settings. |
| 273 | * |
| 274 | * The Serial Mux does not support this function. |
| 275 | */ |
| 276 | static void |
| 277 | mux_set_termios(struct uart_port *port, struct termios *termios, |
| 278 | struct termios *old) |
| 279 | { |
| 280 | } |
| 281 | |
| 282 | /** |
| 283 | * mux_type - Describe the port. |
| 284 | * @port: Ptr to the uart_port. |
| 285 | * |
| 286 | * Return a pointer to a string constant describing the |
| 287 | * specified port. |
| 288 | */ |
| 289 | static const char *mux_type(struct uart_port *port) |
| 290 | { |
| 291 | return "Mux"; |
| 292 | } |
| 293 | |
| 294 | /** |
| 295 | * mux_release_port - Release memory and IO regions. |
| 296 | * @port: Ptr to the uart_port. |
| 297 | * |
| 298 | * Release any memory and IO region resources currently in use by |
| 299 | * the port. |
| 300 | */ |
| 301 | static void mux_release_port(struct uart_port *port) |
| 302 | { |
| 303 | } |
| 304 | |
| 305 | /** |
| 306 | * mux_request_port - Request memory and IO regions. |
| 307 | * @port: Ptr to the uart_port. |
| 308 | * |
| 309 | * Request any memory and IO region resources required by the port. |
| 310 | * If any fail, no resources should be registered when this function |
| 311 | * returns, and it should return -EBUSY on failure. |
| 312 | */ |
| 313 | static int mux_request_port(struct uart_port *port) |
| 314 | { |
| 315 | return 0; |
| 316 | } |
| 317 | |
| 318 | /** |
| 319 | * mux_config_port - Perform port autoconfiguration. |
| 320 | * @port: Ptr to the uart_port. |
| 321 | * @type: Bitmask of required configurations. |
| 322 | * |
| 323 | * Perform any autoconfiguration steps for the port. This functino is |
| 324 | * called if the UPF_BOOT_AUTOCONF flag is specified for the port. |
| 325 | * [Note: This is required for now because of a bug in the Serial core. |
| 326 | * rmk has already submitted a patch to linus, should be available for |
| 327 | * 2.5.47.] |
| 328 | */ |
| 329 | static void mux_config_port(struct uart_port *port, int type) |
| 330 | { |
| 331 | port->type = PORT_MUX; |
| 332 | } |
| 333 | |
| 334 | /** |
| 335 | * mux_verify_port - Verify the port information. |
| 336 | * @port: Ptr to the uart_port. |
| 337 | * @ser: Ptr to the serial information. |
| 338 | * |
| 339 | * Verify the new serial port information contained within serinfo is |
| 340 | * suitable for this port type. |
| 341 | */ |
| 342 | static int mux_verify_port(struct uart_port *port, struct serial_struct *ser) |
| 343 | { |
| 344 | if(port->membase == NULL) |
| 345 | return -EINVAL; |
| 346 | |
| 347 | return 0; |
| 348 | } |
| 349 | |
| 350 | /** |
| 351 | * mux_drv_poll - Mux poll function. |
| 352 | * @unused: Unused variable |
| 353 | * |
| 354 | * This function periodically polls the Serial MUX to check for new data. |
| 355 | */ |
| 356 | static void mux_poll(unsigned long unused) |
| 357 | { |
| 358 | int i; |
| 359 | |
| 360 | for(i = 0; i < port_cnt; ++i) { |
| 361 | if(!mux_ports[i].info) |
| 362 | continue; |
| 363 | |
| 364 | mux_read(&mux_ports[i]); |
| 365 | mux_write(&mux_ports[i]); |
| 366 | } |
| 367 | |
| 368 | mod_timer(&mux_timer, jiffies + MUX_POLL_DELAY); |
| 369 | } |
| 370 | |
| 371 | |
| 372 | #ifdef CONFIG_SERIAL_MUX_CONSOLE |
| 373 | static void mux_console_write(struct console *co, const char *s, unsigned count) |
| 374 | { |
| 375 | while(count--) |
| 376 | pdc_iodc_putc(*s++); |
| 377 | } |
| 378 | |
| 379 | static int mux_console_setup(struct console *co, char *options) |
| 380 | { |
| 381 | return 0; |
| 382 | } |
| 383 | |
| 384 | struct tty_driver *mux_console_device(struct console *co, int *index) |
| 385 | { |
| 386 | *index = co->index; |
| 387 | return mux_driver.tty_driver; |
| 388 | } |
| 389 | |
| 390 | static struct console mux_console = { |
| 391 | .name = "ttyB", |
| 392 | .write = mux_console_write, |
| 393 | .device = mux_console_device, |
| 394 | .setup = mux_console_setup, |
| 395 | .flags = CON_ENABLED | CON_PRINTBUFFER, |
| 396 | .index = 0, |
| 397 | }; |
| 398 | |
| 399 | #define MUX_CONSOLE &mux_console |
| 400 | #else |
| 401 | #define MUX_CONSOLE NULL |
| 402 | #endif |
| 403 | |
| 404 | static struct uart_ops mux_pops = { |
| 405 | .tx_empty = mux_tx_empty, |
| 406 | .set_mctrl = mux_set_mctrl, |
| 407 | .get_mctrl = mux_get_mctrl, |
| 408 | .stop_tx = mux_stop_tx, |
| 409 | .start_tx = mux_start_tx, |
| 410 | .stop_rx = mux_stop_rx, |
| 411 | .enable_ms = mux_enable_ms, |
| 412 | .break_ctl = mux_break_ctl, |
| 413 | .startup = mux_startup, |
| 414 | .shutdown = mux_shutdown, |
| 415 | .set_termios = mux_set_termios, |
| 416 | .type = mux_type, |
| 417 | .release_port = mux_release_port, |
| 418 | .request_port = mux_request_port, |
| 419 | .config_port = mux_config_port, |
| 420 | .verify_port = mux_verify_port, |
| 421 | }; |
| 422 | |
| 423 | /** |
| 424 | * mux_probe - Determine if the Serial Mux should claim this device. |
| 425 | * @dev: The parisc device. |
| 426 | * |
| 427 | * Deterimine if the Serial Mux should claim this chip (return 0) |
| 428 | * or not (return 1). |
| 429 | */ |
| 430 | static int __init mux_probe(struct parisc_device *dev) |
| 431 | { |
| 432 | int i, status, ports; |
| 433 | u8 iodc_data[32]; |
| 434 | unsigned long bytecnt; |
| 435 | struct uart_port *port; |
| 436 | |
Matthew Wilcox | 53f01bb | 2005-10-21 22:36:40 -0400 | [diff] [blame] | 437 | status = pdc_iodc_read(&bytecnt, dev->hpa.start, 0, iodc_data, 32); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 438 | if(status != PDC_OK) { |
| 439 | printk(KERN_ERR "Serial mux: Unable to read IODC.\n"); |
| 440 | return 1; |
| 441 | } |
| 442 | |
| 443 | ports = GET_MUX_PORTS(iodc_data); |
| 444 | printk(KERN_INFO "Serial mux driver (%d ports) Revision: 0.3\n", ports); |
| 445 | |
| 446 | if(!port_cnt) { |
| 447 | mux_driver.cons = MUX_CONSOLE; |
| 448 | |
| 449 | status = uart_register_driver(&mux_driver); |
| 450 | if(status) { |
| 451 | printk(KERN_ERR "Serial mux: Unable to register driver.\n"); |
| 452 | return 1; |
| 453 | } |
| 454 | |
| 455 | init_timer(&mux_timer); |
| 456 | mux_timer.function = mux_poll; |
| 457 | } |
| 458 | |
| 459 | for(i = 0; i < ports; ++i, ++port_cnt) { |
| 460 | port = &mux_ports[port_cnt]; |
| 461 | port->iobase = 0; |
Matthew Wilcox | ae8c75c | 2005-10-21 22:58:03 -0400 | [diff] [blame] | 462 | port->mapbase = dev->hpa.start + MUX_OFFSET + |
| 463 | (i * MUX_LINE_OFFSET); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 464 | port->membase = ioremap(port->mapbase, MUX_LINE_OFFSET); |
Russell King | 9b4a161 | 2006-02-05 10:48:10 +0000 | [diff] [blame^] | 465 | port->iotype = UPIO_MEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | port->type = PORT_MUX; |
Matthew Wilcox | ae8c75c | 2005-10-21 22:58:03 -0400 | [diff] [blame] | 467 | port->irq = NO_IRQ; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 468 | port->uartclk = 0; |
| 469 | port->fifosize = MUX_FIFO_SIZE; |
| 470 | port->ops = &mux_pops; |
| 471 | port->flags = UPF_BOOT_AUTOCONF; |
| 472 | port->line = port_cnt; |
Ryan Bradetich | a137ce8 | 2005-11-17 16:38:28 -0500 | [diff] [blame] | 473 | |
| 474 | /* The port->timeout needs to match what is present in |
| 475 | * uart_wait_until_sent in serial_core.c. Otherwise |
| 476 | * the time spent in msleep_interruptable will be very |
| 477 | * long, causing the appearance of a console hang. |
| 478 | */ |
| 479 | port->timeout = HZ / 50; |
Matthew Wilcox | ae8c75c | 2005-10-21 22:58:03 -0400 | [diff] [blame] | 480 | spin_lock_init(&port->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 481 | status = uart_add_one_port(&mux_driver, port); |
| 482 | BUG_ON(status); |
| 483 | } |
| 484 | |
| 485 | #ifdef CONFIG_SERIAL_MUX_CONSOLE |
| 486 | register_console(&mux_console); |
| 487 | #endif |
| 488 | return 0; |
| 489 | } |
| 490 | |
| 491 | static struct parisc_device_id mux_tbl[] = { |
| 492 | { HPHW_A_DIRECT, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x0000D }, |
| 493 | { 0, } |
| 494 | }; |
| 495 | |
| 496 | MODULE_DEVICE_TABLE(parisc, mux_tbl); |
| 497 | |
| 498 | static struct parisc_driver serial_mux_driver = { |
Matthew Wilcox | bdad1f8 | 2005-10-21 22:36:23 -0400 | [diff] [blame] | 499 | .name = "serial_mux", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 500 | .id_table = mux_tbl, |
| 501 | .probe = mux_probe, |
| 502 | }; |
| 503 | |
| 504 | /** |
| 505 | * mux_init - Serial MUX initalization procedure. |
| 506 | * |
| 507 | * Register the Serial MUX driver. |
| 508 | */ |
| 509 | static int __init mux_init(void) |
| 510 | { |
| 511 | return register_parisc_driver(&serial_mux_driver); |
| 512 | } |
| 513 | |
| 514 | /** |
| 515 | * mux_exit - Serial MUX cleanup procedure. |
| 516 | * |
| 517 | * Unregister the Serial MUX driver from the tty layer. |
| 518 | */ |
| 519 | static void __exit mux_exit(void) |
| 520 | { |
| 521 | int i; |
| 522 | |
| 523 | for (i = 0; i < port_cnt; i++) { |
| 524 | uart_remove_one_port(&mux_driver, &mux_ports[i]); |
| 525 | } |
| 526 | |
| 527 | uart_unregister_driver(&mux_driver); |
| 528 | } |
| 529 | |
| 530 | module_init(mux_init); |
| 531 | module_exit(mux_exit); |
| 532 | |
| 533 | MODULE_AUTHOR("Ryan Bradetich"); |
| 534 | MODULE_DESCRIPTION("Serial MUX driver"); |
| 535 | MODULE_LICENSE("GPL"); |
| 536 | MODULE_ALIAS_CHARDEV_MAJOR(MUX_MAJOR); |