Root/
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 |
52 | static unsigned int port_cnt __read_mostly; |
53 | struct mux_port { |
54 | struct uart_port port; |
55 | int enabled; |
56 | }; |
57 | static struct mux_port mux_ports[MUX_NR]; |
58 | |
59 | static 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 | |
68 | static 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 | */ |
83 | static 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 | */ |
111 | static 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 | */ |
124 | static 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 | */ |
135 | static 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 | */ |
146 | static 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 | */ |
156 | static 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 | */ |
166 | static 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 | */ |
176 | static 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 | */ |
187 | static 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 | */ |
198 | static 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 | */ |
242 | static 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 | */ |
283 | static 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 | */ |
295 | static 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 | */ |
308 | static void |
309 | mux_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 | */ |
321 | static 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 | */ |
333 | static 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 | */ |
345 | static 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 | */ |
361 | static 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 | */ |
374 | static 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 | */ |
388 | static 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 |
405 | static 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 | |
420 | static int mux_console_setup(struct console *co, char *options) |
421 | { |
422 | return 0; |
423 | } |
424 | |
425 | struct tty_driver *mux_console_device(struct console *co, int *index) |
426 | { |
427 | *index = co->index; |
428 | return mux_driver.tty_driver; |
429 | } |
430 | |
431 | static 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 | |
445 | static 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 | */ |
471 | static 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 | |
522 | static 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 | */ |
555 | static 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 | |
561 | static struct parisc_device_id mux_tbl[] = { |
562 | { HPHW_A_DIRECT, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x0000D }, |
563 | { 0, } |
564 | }; |
565 | |
566 | MODULE_DEVICE_TABLE(parisc, builtin_mux_tbl); |
567 | MODULE_DEVICE_TABLE(parisc, mux_tbl); |
568 | |
569 | static 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 | |
576 | static 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 | */ |
588 | static 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 | */ |
612 | static 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 | |
627 | module_init(mux_init); |
628 | module_exit(mux_exit); |
629 | |
630 | MODULE_AUTHOR("Ryan Bradetich"); |
631 | MODULE_DESCRIPTION("Serial MUX driver"); |
632 | MODULE_LICENSE("GPL"); |
633 | MODULE_ALIAS_CHARDEV_MAJOR(MUX_MAJOR); |
634 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9