Loading...
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/module.h>
20#include <linux/tty.h>
21#include <linux/ioport.h>
22#include <linux/init.h>
23#include <linux/serial.h>
24#include <linux/console.h>
25#include <linux/delay.h> /* for udelay */
26#include <linux/device.h>
27#include <asm/io.h>
28#include <asm/irq.h>
29#include <asm/parisc-device.h>
30
31#ifdef CONFIG_MAGIC_SYSRQ
32#include <linux/sysrq.h>
33#define SUPPORT_SYSRQ
34#endif
35
36#include <linux/serial_core.h>
37
38#define MUX_OFFSET 0x800
39#define MUX_LINE_OFFSET 0x80
40
41#define MUX_FIFO_SIZE 255
42#define MUX_POLL_DELAY (30 * HZ / 1000)
43
44#define IO_DATA_REG_OFFSET 0x3c
45#define IO_DCOUNT_REG_OFFSET 0x40
46
47#define MUX_EOFIFO(status) ((status & 0xF000) == 0xF000)
48#define MUX_STATUS(status) ((status & 0xF000) == 0x8000)
49#define MUX_BREAK(status) ((status & 0xF000) == 0x2000)
50
51#define MUX_NR 256
52static unsigned int port_cnt __read_mostly;
53struct mux_port {
54 struct uart_port port;
55 int enabled;
56};
57static struct mux_port mux_ports[MUX_NR];
58
59static struct uart_driver mux_driver = {
60 .owner = THIS_MODULE,
61 .driver_name = "ttyB",
62 .dev_name = "ttyB",
63 .major = MUX_MAJOR,
64 .minor = 0,
65 .nr = MUX_NR,
66};
67
68static struct timer_list mux_timer;
69
70#define UART_PUT_CHAR(p, c) __raw_writel((c), (p)->membase + IO_DATA_REG_OFFSET)
71#define UART_GET_FIFO_CNT(p) __raw_readl((p)->membase + IO_DCOUNT_REG_OFFSET)
72
73/**
74 * get_mux_port_count - Get the number of available ports on the Mux.
75 * @dev: The parisc device.
76 *
77 * This function is used to determine the number of ports the Mux
78 * supports. The IODC data reports the number of ports the Mux
79 * can support, but there are cases where not all the Mux ports
80 * are connected. This function can override the IODC and
81 * return the true port count.
82 */
83static int __init get_mux_port_count(struct parisc_device *dev)
84{
85 int status;
86 u8 iodc_data[32];
87 unsigned long bytecnt;
88
89 /* If this is the built-in Mux for the K-Class (Eole CAP/MUX),
90 * we only need to allocate resources for 1 port since the
91 * other 7 ports are not connected.
92 */
93 if(dev->id.hversion == 0x15)
94 return 1;
95
96 status = pdc_iodc_read(&bytecnt, dev->hpa.start, 0, iodc_data, 32);
97 BUG_ON(status != PDC_OK);
98
99 /* Return the number of ports specified in the iodc data. */
100 return ((((iodc_data)[4] & 0xf0) >> 4) * 8) + 8;
101}
102
103/**
104 * mux_tx_empty - Check if the transmitter fifo is empty.
105 * @port: Ptr to the uart_port.
106 *
107 * This function test if the transmitter fifo for the port
108 * described by 'port' is empty. If it is empty, this function
109 * should return TIOCSER_TEMT, otherwise return 0.
110 */
111static unsigned int mux_tx_empty(struct uart_port *port)
112{
113 return UART_GET_FIFO_CNT(port) ? 0 : TIOCSER_TEMT;
114}
115
116/**
117 * mux_set_mctrl - Set the current state of the modem control inputs.
118 * @ports: Ptr to the uart_port.
119 * @mctrl: Modem control bits.
120 *
121 * The Serial MUX does not support CTS, DCD or DSR so this function
122 * is ignored.
123 */
124static void mux_set_mctrl(struct uart_port *port, unsigned int mctrl)
125{
126}
127
128/**
129 * mux_get_mctrl - Returns the current state of modem control inputs.
130 * @port: Ptr to the uart_port.
131 *
132 * The Serial MUX does not support CTS, DCD or DSR so these lines are
133 * treated as permanently active.
134 */
135static unsigned int mux_get_mctrl(struct uart_port *port)
136{
137 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
138}
139
140/**
141 * mux_stop_tx - Stop transmitting characters.
142 * @port: Ptr to the uart_port.
143 *
144 * The Serial MUX does not support this function.
145 */
146static void mux_stop_tx(struct uart_port *port)
147{
148}
149
150/**
151 * mux_start_tx - Start transmitting characters.
152 * @port: Ptr to the uart_port.
153 *
154 * The Serial Mux does not support this function.
155 */
156static void mux_start_tx(struct uart_port *port)
157{
158}
159
160/**
161 * mux_stop_rx - Stop receiving characters.
162 * @port: Ptr to the uart_port.
163 *
164 * The Serial Mux does not support this function.
165 */
166static void mux_stop_rx(struct uart_port *port)
167{
168}
169
170/**
171 * mux_enable_ms - Enable modum status interrupts.
172 * @port: Ptr to the uart_port.
173 *
174 * The Serial Mux does not support this function.
175 */
176static void mux_enable_ms(struct uart_port *port)
177{
178}
179
180/**
181 * mux_break_ctl - Control the transmitssion of a break signal.
182 * @port: Ptr to the uart_port.
183 * @break_state: Raise/Lower the break signal.
184 *
185 * The Serial Mux does not support this function.
186 */
187static void mux_break_ctl(struct uart_port *port, int break_state)
188{
189}
190
191/**
192 * mux_write - Write chars to the mux fifo.
193 * @port: Ptr to the uart_port.
194 *
195 * This function writes all the data from the uart buffer to
196 * the mux fifo.
197 */
198static void mux_write(struct uart_port *port)
199{
200 int count;
201 struct circ_buf *xmit = &port->state->xmit;
202
203 if(port->x_char) {
204 UART_PUT_CHAR(port, port->x_char);
205 port->icount.tx++;
206 port->x_char = 0;
207 return;
208 }
209
210 if(uart_circ_empty(xmit) || uart_tx_stopped(port)) {
211 mux_stop_tx(port);
212 return;
213 }
214
215 count = (port->fifosize) - UART_GET_FIFO_CNT(port);
216 do {
217 UART_PUT_CHAR(port, xmit->buf[xmit->tail]);
218 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
219 port->icount.tx++;
220 if(uart_circ_empty(xmit))
221 break;
222
223 } while(--count > 0);
224
225 while(UART_GET_FIFO_CNT(port))
226 udelay(1);
227
228 if(uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
229 uart_write_wakeup(port);
230
231 if (uart_circ_empty(xmit))
232 mux_stop_tx(port);
233}
234
235/**
236 * mux_read - Read chars from the mux fifo.
237 * @port: Ptr to the uart_port.
238 *
239 * This reads all available data from the mux's fifo and pushes
240 * the data to the tty layer.
241 */
242static void mux_read(struct uart_port *port)
243{
244 int data;
245 struct tty_struct *tty = port->state->port.tty;
246 __u32 start_count = port->icount.rx;
247
248 while(1) {
249 data = __raw_readl(port->membase + IO_DATA_REG_OFFSET);
250
251 if (MUX_STATUS(data))
252 continue;
253
254 if (MUX_EOFIFO(data))
255 break;
256
257 port->icount.rx++;
258
259 if (MUX_BREAK(data)) {
260 port->icount.brk++;
261 if(uart_handle_break(port))
262 continue;
263 }
264
265 if (uart_handle_sysrq_char(port, data & 0xffu))
266 continue;
267
268 tty_insert_flip_char(tty, data & 0xFF, TTY_NORMAL);
269 }
270
271 if (start_count != port->icount.rx) {
272 tty_flip_buffer_push(tty);
273 }
274}
275
276/**
277 * mux_startup - Initialize the port.
278 * @port: Ptr to the uart_port.
279 *
280 * Grab any resources needed for this port and start the
281 * mux timer.
282 */
283static int mux_startup(struct uart_port *port)
284{
285 mux_ports[port->line].enabled = 1;
286 return 0;
287}
288
289/**
290 * mux_shutdown - Disable the port.
291 * @port: Ptr to the uart_port.
292 *
293 * Release any resources needed for the port.
294 */
295static void mux_shutdown(struct uart_port *port)
296{
297 mux_ports[port->line].enabled = 0;
298}
299
300/**
301 * mux_set_termios - Chane port parameters.
302 * @port: Ptr to the uart_port.
303 * @termios: new termios settings.
304 * @old: old termios settings.
305 *
306 * The Serial Mux does not support this function.
307 */
308static void
309mux_set_termios(struct uart_port *port, struct ktermios *termios,
310 struct ktermios *old)
311{
312}
313
314/**
315 * mux_type - Describe the port.
316 * @port: Ptr to the uart_port.
317 *
318 * Return a pointer to a string constant describing the
319 * specified port.
320 */
321static const char *mux_type(struct uart_port *port)
322{
323 return "Mux";
324}
325
326/**
327 * mux_release_port - Release memory and IO regions.
328 * @port: Ptr to the uart_port.
329 *
330 * Release any memory and IO region resources currently in use by
331 * the port.
332 */
333static void mux_release_port(struct uart_port *port)
334{
335}
336
337/**
338 * mux_request_port - Request memory and IO regions.
339 * @port: Ptr to the uart_port.
340 *
341 * Request any memory and IO region resources required by the port.
342 * If any fail, no resources should be registered when this function
343 * returns, and it should return -EBUSY on failure.
344 */
345static int mux_request_port(struct uart_port *port)
346{
347 return 0;
348}
349
350/**
351 * mux_config_port - Perform port autoconfiguration.
352 * @port: Ptr to the uart_port.
353 * @type: Bitmask of required configurations.
354 *
355 * Perform any autoconfiguration steps for the port. This function is
356 * called if the UPF_BOOT_AUTOCONF flag is specified for the port.
357 * [Note: This is required for now because of a bug in the Serial core.
358 * rmk has already submitted a patch to linus, should be available for
359 * 2.5.47.]
360 */
361static void mux_config_port(struct uart_port *port, int type)
362{
363 port->type = PORT_MUX;
364}
365
366/**
367 * mux_verify_port - Verify the port information.
368 * @port: Ptr to the uart_port.
369 * @ser: Ptr to the serial information.
370 *
371 * Verify the new serial port information contained within serinfo is
372 * suitable for this port type.
373 */
374static int mux_verify_port(struct uart_port *port, struct serial_struct *ser)
375{
376 if(port->membase == NULL)
377 return -EINVAL;
378
379 return 0;
380}
381
382/**
383 * mux_drv_poll - Mux poll function.
384 * @unused: Unused variable
385 *
386 * This function periodically polls the Serial MUX to check for new data.
387 */
388static void mux_poll(unsigned long unused)
389{
390 int i;
391
392 for(i = 0; i < port_cnt; ++i) {
393 if(!mux_ports[i].enabled)
394 continue;
395
396 mux_read(&mux_ports[i].port);
397 mux_write(&mux_ports[i].port);
398 }
399
400 mod_timer(&mux_timer, jiffies + MUX_POLL_DELAY);
401}
402
403
404#ifdef CONFIG_SERIAL_MUX_CONSOLE
405static void mux_console_write(struct console *co, const char *s, unsigned count)
406{
407 /* Wait until the FIFO drains. */
408 while(UART_GET_FIFO_CNT(&mux_ports[0].port))
409 udelay(1);
410
411 while(count--) {
412 if(*s == '\n') {
413 UART_PUT_CHAR(&mux_ports[0].port, '\r');
414 }
415 UART_PUT_CHAR(&mux_ports[0].port, *s++);
416 }
417
418}
419
420static int mux_console_setup(struct console *co, char *options)
421{
422 return 0;
423}
424
425struct tty_driver *mux_console_device(struct console *co, int *index)
426{
427 *index = co->index;
428 return mux_driver.tty_driver;
429}
430
431static struct console mux_console = {
432 .name = "ttyB",
433 .write = mux_console_write,
434 .device = mux_console_device,
435 .setup = mux_console_setup,
436 .flags = CON_ENABLED | CON_PRINTBUFFER,
437 .index = 0,
438};
439
440#define MUX_CONSOLE &mux_console
441#else
442#define MUX_CONSOLE NULL
443#endif
444
445static struct uart_ops mux_pops = {
446 .tx_empty = mux_tx_empty,
447 .set_mctrl = mux_set_mctrl,
448 .get_mctrl = mux_get_mctrl,
449 .stop_tx = mux_stop_tx,
450 .start_tx = mux_start_tx,
451 .stop_rx = mux_stop_rx,
452 .enable_ms = mux_enable_ms,
453 .break_ctl = mux_break_ctl,
454 .startup = mux_startup,
455 .shutdown = mux_shutdown,
456 .set_termios = mux_set_termios,
457 .type = mux_type,
458 .release_port = mux_release_port,
459 .request_port = mux_request_port,
460 .config_port = mux_config_port,
461 .verify_port = mux_verify_port,
462};
463
464/**
465 * mux_probe - Determine if the Serial Mux should claim this device.
466 * @dev: The parisc device.
467 *
468 * Deterimine if the Serial Mux should claim this chip (return 0)
469 * or not (return 1).
470 */
471static int __init mux_probe(struct parisc_device *dev)
472{
473 int i, status;
474
475 int port_count = get_mux_port_count(dev);
476 printk(KERN_INFO "Serial mux driver (%d ports) Revision: 0.6\n", port_count);
477
478 dev_set_drvdata(&dev->dev, (void *)(long)port_count);
479 request_mem_region(dev->hpa.start + MUX_OFFSET,
480 port_count * MUX_LINE_OFFSET, "Mux");
481
482 if(!port_cnt) {
483 mux_driver.cons = MUX_CONSOLE;
484
485 status = uart_register_driver(&mux_driver);
486 if(status) {
487 printk(KERN_ERR "Serial mux: Unable to register driver.\n");
488 return 1;
489 }
490 }
491
492 for(i = 0; i < port_count; ++i, ++port_cnt) {
493 struct uart_port *port = &mux_ports[port_cnt].port;
494 port->iobase = 0;
495 port->mapbase = dev->hpa.start + MUX_OFFSET +
496 (i * MUX_LINE_OFFSET);
497 port->membase = ioremap_nocache(port->mapbase, MUX_LINE_OFFSET);
498 port->iotype = UPIO_MEM;
499 port->type = PORT_MUX;
500 port->irq = NO_IRQ;
501 port->uartclk = 0;
502 port->fifosize = MUX_FIFO_SIZE;
503 port->ops = &mux_pops;
504 port->flags = UPF_BOOT_AUTOCONF;
505 port->line = port_cnt;
506
507 /* The port->timeout needs to match what is present in
508 * uart_wait_until_sent in serial_core.c. Otherwise
509 * the time spent in msleep_interruptable will be very
510 * long, causing the appearance of a console hang.
511 */
512 port->timeout = HZ / 50;
513 spin_lock_init(&port->lock);
514
515 status = uart_add_one_port(&mux_driver, port);
516 BUG_ON(status);
517 }
518
519 return 0;
520}
521
522static int __devexit mux_remove(struct parisc_device *dev)
523{
524 int i, j;
525 int port_count = (long)dev_get_drvdata(&dev->dev);
526
527 /* Find Port 0 for this card in the mux_ports list. */
528 for(i = 0; i < port_cnt; ++i) {
529 if(mux_ports[i].port.mapbase == dev->hpa.start + MUX_OFFSET)
530 break;
531 }
532 BUG_ON(i + port_count > port_cnt);
533
534 /* Release the resources associated with each port on the device. */
535 for(j = 0; j < port_count; ++j, ++i) {
536 struct uart_port *port = &mux_ports[i].port;
537
538 uart_remove_one_port(&mux_driver, port);
539 if(port->membase)
540 iounmap(port->membase);
541 }
542
543 release_mem_region(dev->hpa.start + MUX_OFFSET, port_count * MUX_LINE_OFFSET);
544 return 0;
545}
546
547/* Hack. This idea was taken from the 8250_gsc.c on how to properly order
548 * the serial port detection in the proper order. The idea is we always
549 * want the builtin mux to be detected before addin mux cards, so we
550 * specifically probe for the builtin mux cards first.
551 *
552 * This table only contains the parisc_device_id of known builtin mux
553 * devices. All other mux cards will be detected by the generic mux_tbl.
554 */
555static struct parisc_device_id builtin_mux_tbl[] = {
556 { HPHW_A_DIRECT, HVERSION_REV_ANY_ID, 0x15, 0x0000D }, /* All K-class */
557 { HPHW_A_DIRECT, HVERSION_REV_ANY_ID, 0x44, 0x0000D }, /* E35, E45, and E55 */
558 { 0, }
559};
560
561static struct parisc_device_id mux_tbl[] = {
562 { HPHW_A_DIRECT, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x0000D },
563 { 0, }
564};
565
566MODULE_DEVICE_TABLE(parisc, builtin_mux_tbl);
567MODULE_DEVICE_TABLE(parisc, mux_tbl);
568
569static struct parisc_driver builtin_serial_mux_driver = {
570 .name = "builtin_serial_mux",
571 .id_table = builtin_mux_tbl,
572 .probe = mux_probe,
573 .remove = __devexit_p(mux_remove),
574};
575
576static struct parisc_driver serial_mux_driver = {
577 .name = "serial_mux",
578 .id_table = mux_tbl,
579 .probe = mux_probe,
580 .remove = __devexit_p(mux_remove),
581};
582
583/**
584 * mux_init - Serial MUX initialization procedure.
585 *
586 * Register the Serial MUX driver.
587 */
588static int __init mux_init(void)
589{
590 register_parisc_driver(&builtin_serial_mux_driver);
591 register_parisc_driver(&serial_mux_driver);
592
593 if(port_cnt > 0) {
594 /* Start the Mux timer */
595 init_timer(&mux_timer);
596 mux_timer.function = mux_poll;
597 mod_timer(&mux_timer, jiffies + MUX_POLL_DELAY);
598
599#ifdef CONFIG_SERIAL_MUX_CONSOLE
600 register_console(&mux_console);
601#endif
602 }
603
604 return 0;
605}
606
607/**
608 * mux_exit - Serial MUX cleanup procedure.
609 *
610 * Unregister the Serial MUX driver from the tty layer.
611 */
612static void __exit mux_exit(void)
613{
614 /* Delete the Mux timer. */
615 if(port_cnt > 0) {
616 del_timer(&mux_timer);
617#ifdef CONFIG_SERIAL_MUX_CONSOLE
618 unregister_console(&mux_console);
619#endif
620 }
621
622 unregister_parisc_driver(&builtin_serial_mux_driver);
623 unregister_parisc_driver(&serial_mux_driver);
624 uart_unregister_driver(&mux_driver);
625}
626
627module_init(mux_init);
628module_exit(mux_exit);
629
630MODULE_AUTHOR("Ryan Bradetich");
631MODULE_DESCRIPTION("Serial MUX driver");
632MODULE_LICENSE("GPL");
633MODULE_ALIAS_CHARDEV_MAJOR(MUX_MAJOR);
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/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>
31
32#ifdef CONFIG_MAGIC_SYSRQ
33#include <linux/sysrq.h>
34#define SUPPORT_SYSRQ
35#endif
36
37#include <linux/serial_core.h>
38
39#define MUX_OFFSET 0x800
40#define MUX_LINE_OFFSET 0x80
41
42#define MUX_FIFO_SIZE 255
43#define MUX_POLL_DELAY (30 * HZ / 1000)
44
45#define IO_DATA_REG_OFFSET 0x3c
46#define IO_DCOUNT_REG_OFFSET 0x40
47
48#define MUX_EOFIFO(status) ((status & 0xF000) == 0xF000)
49#define MUX_STATUS(status) ((status & 0xF000) == 0x8000)
50#define MUX_BREAK(status) ((status & 0xF000) == 0x2000)
51
52#define MUX_NR 256
53static unsigned int port_cnt __read_mostly;
54struct mux_port {
55 struct uart_port port;
56 int enabled;
57};
58static struct mux_port mux_ports[MUX_NR];
59
60static 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,
67};
68
69static struct timer_list mux_timer;
70
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)
73
74/**
75 * get_mux_port_count - Get the number of available ports on the Mux.
76 * @dev: The parisc device.
77 *
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.
83 */
84static int __init get_mux_port_count(struct parisc_device *dev)
85{
86 int status;
87 u8 iodc_data[32];
88 unsigned long bytecnt;
89
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.
93 */
94 if(dev->id.hversion == 0x15)
95 return 1;
96
97 status = pdc_iodc_read(&bytecnt, dev->hpa.start, 0, iodc_data, 32);
98 BUG_ON(status != PDC_OK);
99
100 /* Return the number of ports specified in the iodc data. */
101 return ((((iodc_data)[4] & 0xf0) >> 4) * 8) + 8;
102}
103
104/**
105 * mux_tx_empty - Check if the transmitter fifo is empty.
106 * @port: Ptr to the uart_port.
107 *
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.
111 */
112static unsigned int mux_tx_empty(struct uart_port *port)
113{
114 return UART_GET_FIFO_CNT(port) ? 0 : TIOCSER_TEMT;
115}
116
117/**
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.
121 *
122 * The Serial MUX does not support CTS, DCD or DSR so this function
123 * is ignored.
124 */
125static void mux_set_mctrl(struct uart_port *port, unsigned int mctrl)
126{
127}
128
129/**
130 * mux_get_mctrl - Returns the current state of modem control inputs.
131 * @port: Ptr to the uart_port.
132 *
133 * The Serial MUX does not support CTS, DCD or DSR so these lines are
134 * treated as permanently active.
135 */
136static unsigned int mux_get_mctrl(struct uart_port *port)
137{
138 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
139}
140
141/**
142 * mux_stop_tx - Stop transmitting characters.
143 * @port: Ptr to the uart_port.
144 *
145 * The Serial MUX does not support this function.
146 */
147static void mux_stop_tx(struct uart_port *port)
148{
149}
150
151/**
152 * mux_start_tx - Start transmitting characters.
153 * @port: Ptr to the uart_port.
154 *
155 * The Serial Mux does not support this function.
156 */
157static void mux_start_tx(struct uart_port *port)
158{
159}
160
161/**
162 * mux_stop_rx - Stop receiving characters.
163 * @port: Ptr to the uart_port.
164 *
165 * The Serial Mux does not support this function.
166 */
167static void mux_stop_rx(struct uart_port *port)
168{
169}
170
171/**
172 * mux_enable_ms - Enable modum status interrupts.
173 * @port: Ptr to the uart_port.
174 *
175 * The Serial Mux does not support this function.
176 */
177static void mux_enable_ms(struct uart_port *port)
178{
179}
180
181/**
182 * mux_break_ctl - Control the transmitssion of a break signal.
183 * @port: Ptr to the uart_port.
184 * @break_state: Raise/Lower the break signal.
185 *
186 * The Serial Mux does not support this function.
187 */
188static void mux_break_ctl(struct uart_port *port, int break_state)
189{
190}
191
192/**
193 * mux_write - Write chars to the mux fifo.
194 * @port: Ptr to the uart_port.
195 *
196 * This function writes all the data from the uart buffer to
197 * the mux fifo.
198 */
199static void mux_write(struct uart_port *port)
200{
201 int count;
202 struct circ_buf *xmit = &port->state->xmit;
203
204 if(port->x_char) {
205 UART_PUT_CHAR(port, port->x_char);
206 port->icount.tx++;
207 port->x_char = 0;
208 return;
209 }
210
211 if(uart_circ_empty(xmit) || uart_tx_stopped(port)) {
212 mux_stop_tx(port);
213 return;
214 }
215
216 count = (port->fifosize) - UART_GET_FIFO_CNT(port);
217 do {
218 UART_PUT_CHAR(port, xmit->buf[xmit->tail]);
219 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
220 port->icount.tx++;
221 if(uart_circ_empty(xmit))
222 break;
223
224 } while(--count > 0);
225
226 while(UART_GET_FIFO_CNT(port))
227 udelay(1);
228
229 if(uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
230 uart_write_wakeup(port);
231
232 if (uart_circ_empty(xmit))
233 mux_stop_tx(port);
234}
235
236/**
237 * mux_read - Read chars from the mux fifo.
238 * @port: Ptr to the uart_port.
239 *
240 * This reads all available data from the mux's fifo and pushes
241 * the data to the tty layer.
242 */
243static void mux_read(struct uart_port *port)
244{
245 int data;
246 struct tty_struct *tty = port->state->port.tty;
247 __u32 start_count = port->icount.rx;
248
249 while(1) {
250 data = __raw_readl(port->membase + IO_DATA_REG_OFFSET);
251
252 if (MUX_STATUS(data))
253 continue;
254
255 if (MUX_EOFIFO(data))
256 break;
257
258 port->icount.rx++;
259
260 if (MUX_BREAK(data)) {
261 port->icount.brk++;
262 if(uart_handle_break(port))
263 continue;
264 }
265
266 if (uart_handle_sysrq_char(port, data & 0xffu))
267 continue;
268
269 tty_insert_flip_char(tty, data & 0xFF, TTY_NORMAL);
270 }
271
272 if (start_count != port->icount.rx) {
273 tty_flip_buffer_push(tty);
274 }
275}
276
277/**
278 * mux_startup - Initialize the port.
279 * @port: Ptr to the uart_port.
280 *
281 * Grab any resources needed for this port and start the
282 * mux timer.
283 */
284static int mux_startup(struct uart_port *port)
285{
286 mux_ports[port->line].enabled = 1;
287 return 0;
288}
289
290/**
291 * mux_shutdown - Disable the port.
292 * @port: Ptr to the uart_port.
293 *
294 * Release any resources needed for the port.
295 */
296static void mux_shutdown(struct uart_port *port)
297{
298 mux_ports[port->line].enabled = 0;
299}
300
301/**
302 * mux_set_termios - Chane port parameters.
303 * @port: Ptr to the uart_port.
304 * @termios: new termios settings.
305 * @old: old termios settings.
306 *
307 * The Serial Mux does not support this function.
308 */
309static void
310mux_set_termios(struct uart_port *port, struct ktermios *termios,
311 struct ktermios *old)
312{
313}
314
315/**
316 * mux_type - Describe the port.
317 * @port: Ptr to the uart_port.
318 *
319 * Return a pointer to a string constant describing the
320 * specified port.
321 */
322static const char *mux_type(struct uart_port *port)
323{
324 return "Mux";
325}
326
327/**
328 * mux_release_port - Release memory and IO regions.
329 * @port: Ptr to the uart_port.
330 *
331 * Release any memory and IO region resources currently in use by
332 * the port.
333 */
334static void mux_release_port(struct uart_port *port)
335{
336}
337
338/**
339 * mux_request_port - Request memory and IO regions.
340 * @port: Ptr to the uart_port.
341 *
342 * Request any memory and IO region resources required by the port.
343 * If any fail, no resources should be registered when this function
344 * returns, and it should return -EBUSY on failure.
345 */
346static int mux_request_port(struct uart_port *port)
347{
348 return 0;
349}
350
351/**
352 * mux_config_port - Perform port autoconfiguration.
353 * @port: Ptr to the uart_port.
354 * @type: Bitmask of required configurations.
355 *
356 * Perform any autoconfiguration steps for the port. This function is
357 * called if the UPF_BOOT_AUTOCONF flag is specified for the port.
358 * [Note: This is required for now because of a bug in the Serial core.
359 * rmk has already submitted a patch to linus, should be available for
360 * 2.5.47.]
361 */
362static void mux_config_port(struct uart_port *port, int type)
363{
364 port->type = PORT_MUX;
365}
366
367/**
368 * mux_verify_port - Verify the port information.
369 * @port: Ptr to the uart_port.
370 * @ser: Ptr to the serial information.
371 *
372 * Verify the new serial port information contained within serinfo is
373 * suitable for this port type.
374 */
375static int mux_verify_port(struct uart_port *port, struct serial_struct *ser)
376{
377 if(port->membase == NULL)
378 return -EINVAL;
379
380 return 0;
381}
382
383/**
384 * mux_drv_poll - Mux poll function.
385 * @unused: Unused variable
386 *
387 * This function periodically polls the Serial MUX to check for new data.
388 */
389static void mux_poll(unsigned long unused)
390{
391 int i;
392
393 for(i = 0; i < port_cnt; ++i) {
394 if(!mux_ports[i].enabled)
395 continue;
396
397 mux_read(&mux_ports[i].port);
398 mux_write(&mux_ports[i].port);
399 }
400
401 mod_timer(&mux_timer, jiffies + MUX_POLL_DELAY);
402}
403
404
405#ifdef CONFIG_SERIAL_MUX_CONSOLE
406static void mux_console_write(struct console *co, const char *s, unsigned count)
407{
408 /* Wait until the FIFO drains. */
409 while(UART_GET_FIFO_CNT(&mux_ports[0].port))
410 udelay(1);
411
412 while(count--) {
413 if(*s == '\n') {
414 UART_PUT_CHAR(&mux_ports[0].port, '\r');
415 }
416 UART_PUT_CHAR(&mux_ports[0].port, *s++);
417 }
418
419}
420
421static int mux_console_setup(struct console *co, char *options)
422{
423 return 0;
424}
425
426struct tty_driver *mux_console_device(struct console *co, int *index)
427{
428 *index = co->index;
429 return mux_driver.tty_driver;
430}
431
432static struct console mux_console = {
433 .name = "ttyB",
434 .write = mux_console_write,
435 .device = mux_console_device,
436 .setup = mux_console_setup,
437 .flags = CON_ENABLED | CON_PRINTBUFFER,
438 .index = 0,
439};
440
441#define MUX_CONSOLE &mux_console
442#else
443#define MUX_CONSOLE NULL
444#endif
445
446static struct uart_ops mux_pops = {
447 .tx_empty = mux_tx_empty,
448 .set_mctrl = mux_set_mctrl,
449 .get_mctrl = mux_get_mctrl,
450 .stop_tx = mux_stop_tx,
451 .start_tx = mux_start_tx,
452 .stop_rx = mux_stop_rx,
453 .enable_ms = mux_enable_ms,
454 .break_ctl = mux_break_ctl,
455 .startup = mux_startup,
456 .shutdown = mux_shutdown,
457 .set_termios = mux_set_termios,
458 .type = mux_type,
459 .release_port = mux_release_port,
460 .request_port = mux_request_port,
461 .config_port = mux_config_port,
462 .verify_port = mux_verify_port,
463};
464
465/**
466 * mux_probe - Determine if the Serial Mux should claim this device.
467 * @dev: The parisc device.
468 *
469 * Deterimine if the Serial Mux should claim this chip (return 0)
470 * or not (return 1).
471 */
472static int __init mux_probe(struct parisc_device *dev)
473{
474 int i, status;
475
476 int port_count = get_mux_port_count(dev);
477 printk(KERN_INFO "Serial mux driver (%d ports) Revision: 0.6\n", port_count);
478
479 dev_set_drvdata(&dev->dev, (void *)(long)port_count);
480 request_mem_region(dev->hpa.start + MUX_OFFSET,
481 port_count * MUX_LINE_OFFSET, "Mux");
482
483 if(!port_cnt) {
484 mux_driver.cons = MUX_CONSOLE;
485
486 status = uart_register_driver(&mux_driver);
487 if(status) {
488 printk(KERN_ERR "Serial mux: Unable to register driver.\n");
489 return 1;
490 }
491 }
492
493 for(i = 0; i < port_count; ++i, ++port_cnt) {
494 struct uart_port *port = &mux_ports[port_cnt].port;
495 port->iobase = 0;
496 port->mapbase = dev->hpa.start + MUX_OFFSET +
497 (i * MUX_LINE_OFFSET);
498 port->membase = ioremap_nocache(port->mapbase, MUX_LINE_OFFSET);
499 port->iotype = UPIO_MEM;
500 port->type = PORT_MUX;
501 port->irq = 0;
502 port->uartclk = 0;
503 port->fifosize = MUX_FIFO_SIZE;
504 port->ops = &mux_pops;
505 port->flags = UPF_BOOT_AUTOCONF;
506 port->line = port_cnt;
507
508 /* The port->timeout needs to match what is present in
509 * uart_wait_until_sent in serial_core.c. Otherwise
510 * the time spent in msleep_interruptable will be very
511 * long, causing the appearance of a console hang.
512 */
513 port->timeout = HZ / 50;
514 spin_lock_init(&port->lock);
515
516 status = uart_add_one_port(&mux_driver, port);
517 BUG_ON(status);
518 }
519
520 return 0;
521}
522
523static int __devexit mux_remove(struct parisc_device *dev)
524{
525 int i, j;
526 int port_count = (long)dev_get_drvdata(&dev->dev);
527
528 /* Find Port 0 for this card in the mux_ports list. */
529 for(i = 0; i < port_cnt; ++i) {
530 if(mux_ports[i].port.mapbase == dev->hpa.start + MUX_OFFSET)
531 break;
532 }
533 BUG_ON(i + port_count > port_cnt);
534
535 /* Release the resources associated with each port on the device. */
536 for(j = 0; j < port_count; ++j, ++i) {
537 struct uart_port *port = &mux_ports[i].port;
538
539 uart_remove_one_port(&mux_driver, port);
540 if(port->membase)
541 iounmap(port->membase);
542 }
543
544 release_mem_region(dev->hpa.start + MUX_OFFSET, port_count * MUX_LINE_OFFSET);
545 return 0;
546}
547
548/* Hack. This idea was taken from the 8250_gsc.c on how to properly order
549 * the serial port detection in the proper order. The idea is we always
550 * want the builtin mux to be detected before addin mux cards, so we
551 * specifically probe for the builtin mux cards first.
552 *
553 * This table only contains the parisc_device_id of known builtin mux
554 * devices. All other mux cards will be detected by the generic mux_tbl.
555 */
556static struct parisc_device_id builtin_mux_tbl[] = {
557 { HPHW_A_DIRECT, HVERSION_REV_ANY_ID, 0x15, 0x0000D }, /* All K-class */
558 { HPHW_A_DIRECT, HVERSION_REV_ANY_ID, 0x44, 0x0000D }, /* E35, E45, and E55 */
559 { 0, }
560};
561
562static struct parisc_device_id mux_tbl[] = {
563 { HPHW_A_DIRECT, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x0000D },
564 { 0, }
565};
566
567MODULE_DEVICE_TABLE(parisc, builtin_mux_tbl);
568MODULE_DEVICE_TABLE(parisc, mux_tbl);
569
570static struct parisc_driver builtin_serial_mux_driver = {
571 .name = "builtin_serial_mux",
572 .id_table = builtin_mux_tbl,
573 .probe = mux_probe,
574 .remove = __devexit_p(mux_remove),
575};
576
577static struct parisc_driver serial_mux_driver = {
578 .name = "serial_mux",
579 .id_table = mux_tbl,
580 .probe = mux_probe,
581 .remove = __devexit_p(mux_remove),
582};
583
584/**
585 * mux_init - Serial MUX initialization procedure.
586 *
587 * Register the Serial MUX driver.
588 */
589static int __init mux_init(void)
590{
591 register_parisc_driver(&builtin_serial_mux_driver);
592 register_parisc_driver(&serial_mux_driver);
593
594 if(port_cnt > 0) {
595 /* Start the Mux timer */
596 init_timer(&mux_timer);
597 mux_timer.function = mux_poll;
598 mod_timer(&mux_timer, jiffies + MUX_POLL_DELAY);
599
600#ifdef CONFIG_SERIAL_MUX_CONSOLE
601 register_console(&mux_console);
602#endif
603 }
604
605 return 0;
606}
607
608/**
609 * mux_exit - Serial MUX cleanup procedure.
610 *
611 * Unregister the Serial MUX driver from the tty layer.
612 */
613static void __exit mux_exit(void)
614{
615 /* Delete the Mux timer. */
616 if(port_cnt > 0) {
617 del_timer(&mux_timer);
618#ifdef CONFIG_SERIAL_MUX_CONSOLE
619 unregister_console(&mux_console);
620#endif
621 }
622
623 unregister_parisc_driver(&builtin_serial_mux_driver);
624 unregister_parisc_driver(&serial_mux_driver);
625 uart_unregister_driver(&mux_driver);
626}
627
628module_init(mux_init);
629module_exit(mux_exit);
630
631MODULE_AUTHOR("Ryan Bradetich");
632MODULE_DESCRIPTION("Serial MUX driver");
633MODULE_LICENSE("GPL");
634MODULE_ALIAS_CHARDEV_MAJOR(MUX_MAJOR);