sh_eth: fix EESIPR values for SH77{34|63}
[linux/fpc-iii.git] / drivers / tty / serial / mux.c
blob8a4be4b73723381a6bcba7b89cb1137ed3b5ac96
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.
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.
19 #include <linux/module.h>
20 #include <linux/ioport.h>
21 #include <linux/init.h>
22 #include <linux/serial.h>
23 #include <linux/tty.h>
24 #include <linux/tty_flip.h>
25 #include <linux/console.h>
26 #include <linux/delay.h> /* for udelay */
27 #include <linux/device.h>
28 #include <asm/io.h>
29 #include <asm/irq.h>
30 #include <asm/parisc-device.h>
32 #if defined(CONFIG_SERIAL_MUX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
33 #include <linux/sysrq.h>
34 #define SUPPORT_SYSRQ
35 #endif
37 #include <linux/serial_core.h>
39 #define MUX_OFFSET 0x800
40 #define MUX_LINE_OFFSET 0x80
42 #define MUX_FIFO_SIZE 255
43 #define MUX_POLL_DELAY (30 * HZ / 1000)
45 #define IO_DATA_REG_OFFSET 0x3c
46 #define IO_DCOUNT_REG_OFFSET 0x40
48 #define MUX_EOFIFO(status) ((status & 0xF000) == 0xF000)
49 #define MUX_STATUS(status) ((status & 0xF000) == 0x8000)
50 #define MUX_BREAK(status) ((status & 0xF000) == 0x2000)
52 #define MUX_NR 256
53 static unsigned int port_cnt __read_mostly;
54 struct mux_port {
55 struct uart_port port;
56 int enabled;
58 static struct mux_port mux_ports[MUX_NR];
60 static struct uart_driver mux_driver = {
61 .owner = THIS_MODULE,
62 .driver_name = "ttyB",
63 .dev_name = "ttyB",
64 .major = MUX_MAJOR,
65 .minor = 0,
66 .nr = MUX_NR,
69 static struct timer_list mux_timer;
71 #define UART_PUT_CHAR(p, c) __raw_writel((c), (p)->membase + IO_DATA_REG_OFFSET)
72 #define UART_GET_FIFO_CNT(p) __raw_readl((p)->membase + IO_DCOUNT_REG_OFFSET)
74 /**
75 * get_mux_port_count - Get the number of available ports on the Mux.
76 * @dev: The parisc device.
78 * This function is used to determine the number of ports the Mux
79 * supports. The IODC data reports the number of ports the Mux
80 * can support, but there are cases where not all the Mux ports
81 * are connected. This function can override the IODC and
82 * return the true port count.
84 static int __init get_mux_port_count(struct parisc_device *dev)
86 int status;
87 u8 iodc_data[32];
88 unsigned long bytecnt;
90 /* If this is the built-in Mux for the K-Class (Eole CAP/MUX),
91 * we only need to allocate resources for 1 port since the
92 * other 7 ports are not connected.
94 if(dev->id.hversion == 0x15)
95 return 1;
97 status = pdc_iodc_read(&bytecnt, dev->hpa.start, 0, iodc_data, 32);
98 BUG_ON(status != PDC_OK);
100 /* Return the number of ports specified in the iodc data. */
101 return ((((iodc_data)[4] & 0xf0) >> 4) * 8) + 8;
105 * mux_tx_empty - Check if the transmitter fifo is empty.
106 * @port: Ptr to the uart_port.
108 * This function test if the transmitter fifo for the port
109 * described by 'port' is empty. If it is empty, this function
110 * should return TIOCSER_TEMT, otherwise return 0.
112 static unsigned int mux_tx_empty(struct uart_port *port)
114 return UART_GET_FIFO_CNT(port) ? 0 : TIOCSER_TEMT;
118 * mux_set_mctrl - Set the current state of the modem control inputs.
119 * @ports: Ptr to the uart_port.
120 * @mctrl: Modem control bits.
122 * The Serial MUX does not support CTS, DCD or DSR so this function
123 * is ignored.
125 static void mux_set_mctrl(struct uart_port *port, unsigned int mctrl)
130 * mux_get_mctrl - Returns the current state of modem control inputs.
131 * @port: Ptr to the uart_port.
133 * The Serial MUX does not support CTS, DCD or DSR so these lines are
134 * treated as permanently active.
136 static unsigned int mux_get_mctrl(struct uart_port *port)
138 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
142 * mux_stop_tx - Stop transmitting characters.
143 * @port: Ptr to the uart_port.
145 * The Serial MUX does not support this function.
147 static void mux_stop_tx(struct uart_port *port)
152 * mux_start_tx - Start transmitting characters.
153 * @port: Ptr to the uart_port.
155 * The Serial Mux does not support this function.
157 static void mux_start_tx(struct uart_port *port)
162 * mux_stop_rx - Stop receiving characters.
163 * @port: Ptr to the uart_port.
165 * The Serial Mux does not support this function.
167 static void mux_stop_rx(struct uart_port *port)
172 * mux_break_ctl - Control the transmitssion of a break signal.
173 * @port: Ptr to the uart_port.
174 * @break_state: Raise/Lower the break signal.
176 * The Serial Mux does not support this function.
178 static void mux_break_ctl(struct uart_port *port, int break_state)
183 * mux_write - Write chars to the mux fifo.
184 * @port: Ptr to the uart_port.
186 * This function writes all the data from the uart buffer to
187 * the mux fifo.
189 static void mux_write(struct uart_port *port)
191 int count;
192 struct circ_buf *xmit = &port->state->xmit;
194 if(port->x_char) {
195 UART_PUT_CHAR(port, port->x_char);
196 port->icount.tx++;
197 port->x_char = 0;
198 return;
201 if(uart_circ_empty(xmit) || uart_tx_stopped(port)) {
202 mux_stop_tx(port);
203 return;
206 count = (port->fifosize) - UART_GET_FIFO_CNT(port);
207 do {
208 UART_PUT_CHAR(port, xmit->buf[xmit->tail]);
209 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
210 port->icount.tx++;
211 if(uart_circ_empty(xmit))
212 break;
214 } while(--count > 0);
216 while(UART_GET_FIFO_CNT(port))
217 udelay(1);
219 if(uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
220 uart_write_wakeup(port);
222 if (uart_circ_empty(xmit))
223 mux_stop_tx(port);
227 * mux_read - Read chars from the mux fifo.
228 * @port: Ptr to the uart_port.
230 * This reads all available data from the mux's fifo and pushes
231 * the data to the tty layer.
233 static void mux_read(struct uart_port *port)
235 struct tty_port *tport = &port->state->port;
236 int data;
237 __u32 start_count = port->icount.rx;
239 while(1) {
240 data = __raw_readl(port->membase + IO_DATA_REG_OFFSET);
242 if (MUX_STATUS(data))
243 continue;
245 if (MUX_EOFIFO(data))
246 break;
248 port->icount.rx++;
250 if (MUX_BREAK(data)) {
251 port->icount.brk++;
252 if(uart_handle_break(port))
253 continue;
256 if (uart_handle_sysrq_char(port, data & 0xffu))
257 continue;
259 tty_insert_flip_char(tport, data & 0xFF, TTY_NORMAL);
262 if (start_count != port->icount.rx)
263 tty_flip_buffer_push(tport);
267 * mux_startup - Initialize the port.
268 * @port: Ptr to the uart_port.
270 * Grab any resources needed for this port and start the
271 * mux timer.
273 static int mux_startup(struct uart_port *port)
275 mux_ports[port->line].enabled = 1;
276 return 0;
280 * mux_shutdown - Disable the port.
281 * @port: Ptr to the uart_port.
283 * Release any resources needed for the port.
285 static void mux_shutdown(struct uart_port *port)
287 mux_ports[port->line].enabled = 0;
291 * mux_set_termios - Chane port parameters.
292 * @port: Ptr to the uart_port.
293 * @termios: new termios settings.
294 * @old: old termios settings.
296 * The Serial Mux does not support this function.
298 static void
299 mux_set_termios(struct uart_port *port, struct ktermios *termios,
300 struct ktermios *old)
305 * mux_type - Describe the port.
306 * @port: Ptr to the uart_port.
308 * Return a pointer to a string constant describing the
309 * specified port.
311 static const char *mux_type(struct uart_port *port)
313 return "Mux";
317 * mux_release_port - Release memory and IO regions.
318 * @port: Ptr to the uart_port.
320 * Release any memory and IO region resources currently in use by
321 * the port.
323 static void mux_release_port(struct uart_port *port)
328 * mux_request_port - Request memory and IO regions.
329 * @port: Ptr to the uart_port.
331 * Request any memory and IO region resources required by the port.
332 * If any fail, no resources should be registered when this function
333 * returns, and it should return -EBUSY on failure.
335 static int mux_request_port(struct uart_port *port)
337 return 0;
341 * mux_config_port - Perform port autoconfiguration.
342 * @port: Ptr to the uart_port.
343 * @type: Bitmask of required configurations.
345 * Perform any autoconfiguration steps for the port. This function is
346 * called if the UPF_BOOT_AUTOCONF flag is specified for the port.
347 * [Note: This is required for now because of a bug in the Serial core.
348 * rmk has already submitted a patch to linus, should be available for
349 * 2.5.47.]
351 static void mux_config_port(struct uart_port *port, int type)
353 port->type = PORT_MUX;
357 * mux_verify_port - Verify the port information.
358 * @port: Ptr to the uart_port.
359 * @ser: Ptr to the serial information.
361 * Verify the new serial port information contained within serinfo is
362 * suitable for this port type.
364 static int mux_verify_port(struct uart_port *port, struct serial_struct *ser)
366 if(port->membase == NULL)
367 return -EINVAL;
369 return 0;
373 * mux_drv_poll - Mux poll function.
374 * @unused: Unused variable
376 * This function periodically polls the Serial MUX to check for new data.
378 static void mux_poll(unsigned long unused)
380 int i;
382 for(i = 0; i < port_cnt; ++i) {
383 if(!mux_ports[i].enabled)
384 continue;
386 mux_read(&mux_ports[i].port);
387 mux_write(&mux_ports[i].port);
390 mod_timer(&mux_timer, jiffies + MUX_POLL_DELAY);
394 #ifdef CONFIG_SERIAL_MUX_CONSOLE
395 static void mux_console_write(struct console *co, const char *s, unsigned count)
397 /* Wait until the FIFO drains. */
398 while(UART_GET_FIFO_CNT(&mux_ports[0].port))
399 udelay(1);
401 while(count--) {
402 if(*s == '\n') {
403 UART_PUT_CHAR(&mux_ports[0].port, '\r');
405 UART_PUT_CHAR(&mux_ports[0].port, *s++);
410 static int mux_console_setup(struct console *co, char *options)
412 return 0;
415 static struct console mux_console = {
416 .name = "ttyB",
417 .write = mux_console_write,
418 .device = uart_console_device,
419 .setup = mux_console_setup,
420 .flags = CON_ENABLED | CON_PRINTBUFFER,
421 .index = 0,
422 .data = &mux_driver,
425 #define MUX_CONSOLE &mux_console
426 #else
427 #define MUX_CONSOLE NULL
428 #endif
430 static struct uart_ops mux_pops = {
431 .tx_empty = mux_tx_empty,
432 .set_mctrl = mux_set_mctrl,
433 .get_mctrl = mux_get_mctrl,
434 .stop_tx = mux_stop_tx,
435 .start_tx = mux_start_tx,
436 .stop_rx = mux_stop_rx,
437 .break_ctl = mux_break_ctl,
438 .startup = mux_startup,
439 .shutdown = mux_shutdown,
440 .set_termios = mux_set_termios,
441 .type = mux_type,
442 .release_port = mux_release_port,
443 .request_port = mux_request_port,
444 .config_port = mux_config_port,
445 .verify_port = mux_verify_port,
449 * mux_probe - Determine if the Serial Mux should claim this device.
450 * @dev: The parisc device.
452 * Deterimine if the Serial Mux should claim this chip (return 0)
453 * or not (return 1).
455 static int __init mux_probe(struct parisc_device *dev)
457 int i, status;
459 int port_count = get_mux_port_count(dev);
460 printk(KERN_INFO "Serial mux driver (%d ports) Revision: 0.6\n", port_count);
462 dev_set_drvdata(&dev->dev, (void *)(long)port_count);
463 request_mem_region(dev->hpa.start + MUX_OFFSET,
464 port_count * MUX_LINE_OFFSET, "Mux");
466 if(!port_cnt) {
467 mux_driver.cons = MUX_CONSOLE;
469 status = uart_register_driver(&mux_driver);
470 if(status) {
471 printk(KERN_ERR "Serial mux: Unable to register driver.\n");
472 return 1;
476 for(i = 0; i < port_count; ++i, ++port_cnt) {
477 struct uart_port *port = &mux_ports[port_cnt].port;
478 port->iobase = 0;
479 port->mapbase = dev->hpa.start + MUX_OFFSET +
480 (i * MUX_LINE_OFFSET);
481 port->membase = ioremap_nocache(port->mapbase, MUX_LINE_OFFSET);
482 port->iotype = UPIO_MEM;
483 port->type = PORT_MUX;
484 port->irq = 0;
485 port->uartclk = 0;
486 port->fifosize = MUX_FIFO_SIZE;
487 port->ops = &mux_pops;
488 port->flags = UPF_BOOT_AUTOCONF;
489 port->line = port_cnt;
491 /* The port->timeout needs to match what is present in
492 * uart_wait_until_sent in serial_core.c. Otherwise
493 * the time spent in msleep_interruptable will be very
494 * long, causing the appearance of a console hang.
496 port->timeout = HZ / 50;
497 spin_lock_init(&port->lock);
499 status = uart_add_one_port(&mux_driver, port);
500 BUG_ON(status);
503 return 0;
506 static int mux_remove(struct parisc_device *dev)
508 int i, j;
509 int port_count = (long)dev_get_drvdata(&dev->dev);
511 /* Find Port 0 for this card in the mux_ports list. */
512 for(i = 0; i < port_cnt; ++i) {
513 if(mux_ports[i].port.mapbase == dev->hpa.start + MUX_OFFSET)
514 break;
516 BUG_ON(i + port_count > port_cnt);
518 /* Release the resources associated with each port on the device. */
519 for(j = 0; j < port_count; ++j, ++i) {
520 struct uart_port *port = &mux_ports[i].port;
522 uart_remove_one_port(&mux_driver, port);
523 if(port->membase)
524 iounmap(port->membase);
527 release_mem_region(dev->hpa.start + MUX_OFFSET, port_count * MUX_LINE_OFFSET);
528 return 0;
531 /* Hack. This idea was taken from the 8250_gsc.c on how to properly order
532 * the serial port detection in the proper order. The idea is we always
533 * want the builtin mux to be detected before addin mux cards, so we
534 * specifically probe for the builtin mux cards first.
536 * This table only contains the parisc_device_id of known builtin mux
537 * devices. All other mux cards will be detected by the generic mux_tbl.
539 static struct parisc_device_id builtin_mux_tbl[] = {
540 { HPHW_A_DIRECT, HVERSION_REV_ANY_ID, 0x15, 0x0000D }, /* All K-class */
541 { HPHW_A_DIRECT, HVERSION_REV_ANY_ID, 0x44, 0x0000D }, /* E35, E45, and E55 */
542 { 0, }
545 static struct parisc_device_id mux_tbl[] = {
546 { HPHW_A_DIRECT, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x0000D },
547 { 0, }
550 MODULE_DEVICE_TABLE(parisc, builtin_mux_tbl);
551 MODULE_DEVICE_TABLE(parisc, mux_tbl);
553 static struct parisc_driver builtin_serial_mux_driver = {
554 .name = "builtin_serial_mux",
555 .id_table = builtin_mux_tbl,
556 .probe = mux_probe,
557 .remove = mux_remove,
560 static struct parisc_driver serial_mux_driver = {
561 .name = "serial_mux",
562 .id_table = mux_tbl,
563 .probe = mux_probe,
564 .remove = mux_remove,
568 * mux_init - Serial MUX initialization procedure.
570 * Register the Serial MUX driver.
572 static int __init mux_init(void)
574 register_parisc_driver(&builtin_serial_mux_driver);
575 register_parisc_driver(&serial_mux_driver);
577 if(port_cnt > 0) {
578 /* Start the Mux timer */
579 init_timer(&mux_timer);
580 mux_timer.function = mux_poll;
581 mod_timer(&mux_timer, jiffies + MUX_POLL_DELAY);
583 #ifdef CONFIG_SERIAL_MUX_CONSOLE
584 register_console(&mux_console);
585 #endif
588 return 0;
592 * mux_exit - Serial MUX cleanup procedure.
594 * Unregister the Serial MUX driver from the tty layer.
596 static void __exit mux_exit(void)
598 /* Delete the Mux timer. */
599 if(port_cnt > 0) {
600 del_timer_sync(&mux_timer);
601 #ifdef CONFIG_SERIAL_MUX_CONSOLE
602 unregister_console(&mux_console);
603 #endif
606 unregister_parisc_driver(&builtin_serial_mux_driver);
607 unregister_parisc_driver(&serial_mux_driver);
608 uart_unregister_driver(&mux_driver);
611 module_init(mux_init);
612 module_exit(mux_exit);
614 MODULE_AUTHOR("Ryan Bradetich");
615 MODULE_DESCRIPTION("Serial MUX driver");
616 MODULE_LICENSE("GPL");
617 MODULE_ALIAS_CHARDEV_MAJOR(MUX_MAJOR);