1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * UART driver for PNX8XXX SoCs
4 *
5 * Author: Per Hallsmark per.hallsmark@mvista.com
6 * Ported to 2.6 kernel by EmbeddedAlley
7 * Reworked by Vitaly Wool <vitalywool@gmail.com>
8 *
9 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
10 * Copyright (C) 2000 Deep Blue Solutions Ltd.
11 */
12
13 #include <linux/module.h>
14 #include <linux/ioport.h>
15 #include <linux/init.h>
16 #include <linux/console.h>
17 #include <linux/sysrq.h>
18 #include <linux/device.h>
19 #include <linux/platform_device.h>
20 #include <linux/tty.h>
21 #include <linux/tty_flip.h>
22 #include <linux/serial_core.h>
23 #include <linux/serial.h>
24 #include <linux/serial_pnx8xxx.h>
25
26 #include <asm/io.h>
27 #include <asm/irq.h>
28
29 /* We'll be using StrongARM sa1100 serial port major/minor */
30 #define SERIAL_PNX8XXX_MAJOR 204
31 #define MINOR_START 5
32
33 #define NR_PORTS 2
34
35 #define PNX8XXX_ISR_PASS_LIMIT 256
36
37 /*
38 * Convert from ignore_status_mask or read_status_mask to FIFO
39 * and interrupt status bits
40 */
41 #define SM_TO_FIFO(x) ((x) >> 10)
42 #define SM_TO_ISTAT(x) ((x) & 0x000001ff)
43 #define FIFO_TO_SM(x) ((x) << 10)
44 #define ISTAT_TO_SM(x) ((x) & 0x000001ff)
45
46 /*
47 * This is the size of our serial port register set.
48 */
49 #define UART_PORT_SIZE 0x1000
50
51 /*
52 * This determines how often we check the modem status signals
53 * for any change. They generally aren't connected to an IRQ
54 * so we have to poll them. We also check immediately before
55 * filling the TX fifo incase CTS has been dropped.
56 */
57 #define MCTRL_TIMEOUT (250*HZ/1000)
58
59 extern struct pnx8xxx_port pnx8xxx_ports[];
60
serial_in(struct pnx8xxx_port * sport,int offset)61 static inline int serial_in(struct pnx8xxx_port *sport, int offset)
62 {
63 return (__raw_readl(sport->port.membase + offset));
64 }
65
serial_out(struct pnx8xxx_port * sport,int offset,int value)66 static inline void serial_out(struct pnx8xxx_port *sport, int offset, int value)
67 {
68 __raw_writel(value, sport->port.membase + offset);
69 }
70
71 /*
72 * Handle any change of modem status signal since we were last called.
73 */
pnx8xxx_mctrl_check(struct pnx8xxx_port * sport)74 static void pnx8xxx_mctrl_check(struct pnx8xxx_port *sport)
75 {
76 unsigned int status, changed;
77
78 status = sport->port.ops->get_mctrl(&sport->port);
79 changed = status ^ sport->old_status;
80
81 if (changed == 0)
82 return;
83
84 sport->old_status = status;
85
86 if (changed & TIOCM_RI)
87 sport->port.icount.rng++;
88 if (changed & TIOCM_DSR)
89 sport->port.icount.dsr++;
90 if (changed & TIOCM_CAR)
91 uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
92 if (changed & TIOCM_CTS)
93 uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
94
95 wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
96 }
97
98 /*
99 * This is our per-port timeout handler, for checking the
100 * modem status signals.
101 */
pnx8xxx_timeout(struct timer_list * t)102 static void pnx8xxx_timeout(struct timer_list *t)
103 {
104 struct pnx8xxx_port *sport = from_timer(sport, t, timer);
105 unsigned long flags;
106
107 if (sport->port.state) {
108 spin_lock_irqsave(&sport->port.lock, flags);
109 pnx8xxx_mctrl_check(sport);
110 spin_unlock_irqrestore(&sport->port.lock, flags);
111
112 mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
113 }
114 }
115
116 /*
117 * interrupts disabled on entry
118 */
pnx8xxx_stop_tx(struct uart_port * port)119 static void pnx8xxx_stop_tx(struct uart_port *port)
120 {
121 struct pnx8xxx_port *sport =
122 container_of(port, struct pnx8xxx_port, port);
123 u32 ien;
124
125 /* Disable TX intr */
126 ien = serial_in(sport, PNX8XXX_IEN);
127 serial_out(sport, PNX8XXX_IEN, ien & ~PNX8XXX_UART_INT_ALLTX);
128
129 /* Clear all pending TX intr */
130 serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLTX);
131 }
132
133 /*
134 * interrupts may not be disabled on entry
135 */
pnx8xxx_start_tx(struct uart_port * port)136 static void pnx8xxx_start_tx(struct uart_port *port)
137 {
138 struct pnx8xxx_port *sport =
139 container_of(port, struct pnx8xxx_port, port);
140 u32 ien;
141
142 /* Clear all pending TX intr */
143 serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLTX);
144
145 /* Enable TX intr */
146 ien = serial_in(sport, PNX8XXX_IEN);
147 serial_out(sport, PNX8XXX_IEN, ien | PNX8XXX_UART_INT_ALLTX);
148 }
149
150 /*
151 * Interrupts enabled
152 */
pnx8xxx_stop_rx(struct uart_port * port)153 static void pnx8xxx_stop_rx(struct uart_port *port)
154 {
155 struct pnx8xxx_port *sport =
156 container_of(port, struct pnx8xxx_port, port);
157 u32 ien;
158
159 /* Disable RX intr */
160 ien = serial_in(sport, PNX8XXX_IEN);
161 serial_out(sport, PNX8XXX_IEN, ien & ~PNX8XXX_UART_INT_ALLRX);
162
163 /* Clear all pending RX intr */
164 serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLRX);
165 }
166
167 /*
168 * Set the modem control timer to fire immediately.
169 */
pnx8xxx_enable_ms(struct uart_port * port)170 static void pnx8xxx_enable_ms(struct uart_port *port)
171 {
172 struct pnx8xxx_port *sport =
173 container_of(port, struct pnx8xxx_port, port);
174
175 mod_timer(&sport->timer, jiffies);
176 }
177
pnx8xxx_rx_chars(struct pnx8xxx_port * sport)178 static void pnx8xxx_rx_chars(struct pnx8xxx_port *sport)
179 {
180 unsigned int status, ch, flg;
181
182 status = FIFO_TO_SM(serial_in(sport, PNX8XXX_FIFO)) |
183 ISTAT_TO_SM(serial_in(sport, PNX8XXX_ISTAT));
184 while (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFIFO)) {
185 ch = serial_in(sport, PNX8XXX_FIFO) & 0xff;
186
187 sport->port.icount.rx++;
188
189 flg = TTY_NORMAL;
190
191 /*
192 * note that the error handling code is
193 * out of the main execution path
194 */
195 if (status & (FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE |
196 PNX8XXX_UART_FIFO_RXPAR |
197 PNX8XXX_UART_FIFO_RXBRK) |
198 ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN))) {
199 if (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXBRK)) {
200 status &= ~(FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE) |
201 FIFO_TO_SM(PNX8XXX_UART_FIFO_RXPAR));
202 sport->port.icount.brk++;
203 if (uart_handle_break(&sport->port))
204 goto ignore_char;
205 } else if (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXPAR))
206 sport->port.icount.parity++;
207 else if (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE))
208 sport->port.icount.frame++;
209 if (status & ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN))
210 sport->port.icount.overrun++;
211
212 status &= sport->port.read_status_mask;
213
214 if (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXPAR))
215 flg = TTY_PARITY;
216 else if (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE))
217 flg = TTY_FRAME;
218
219 sport->port.sysrq = 0;
220 }
221
222 if (uart_handle_sysrq_char(&sport->port, ch))
223 goto ignore_char;
224
225 uart_insert_char(&sport->port, status,
226 ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN), ch, flg);
227
228 ignore_char:
229 serial_out(sport, PNX8XXX_LCR, serial_in(sport, PNX8XXX_LCR) |
230 PNX8XXX_UART_LCR_RX_NEXT);
231 status = FIFO_TO_SM(serial_in(sport, PNX8XXX_FIFO)) |
232 ISTAT_TO_SM(serial_in(sport, PNX8XXX_ISTAT));
233 }
234
235 spin_unlock(&sport->port.lock);
236 tty_flip_buffer_push(&sport->port.state->port);
237 spin_lock(&sport->port.lock);
238 }
239
pnx8xxx_tx_chars(struct pnx8xxx_port * sport)240 static void pnx8xxx_tx_chars(struct pnx8xxx_port *sport)
241 {
242 struct circ_buf *xmit = &sport->port.state->xmit;
243
244 if (sport->port.x_char) {
245 serial_out(sport, PNX8XXX_FIFO, sport->port.x_char);
246 sport->port.icount.tx++;
247 sport->port.x_char = 0;
248 return;
249 }
250
251 /*
252 * Check the modem control lines before
253 * transmitting anything.
254 */
255 pnx8xxx_mctrl_check(sport);
256
257 if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
258 pnx8xxx_stop_tx(&sport->port);
259 return;
260 }
261
262 /*
263 * TX while bytes available
264 */
265 while (((serial_in(sport, PNX8XXX_FIFO) &
266 PNX8XXX_UART_FIFO_TXFIFO) >> 16) < 16) {
267 serial_out(sport, PNX8XXX_FIFO, xmit->buf[xmit->tail]);
268 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
269 sport->port.icount.tx++;
270 if (uart_circ_empty(xmit))
271 break;
272 }
273
274 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
275 uart_write_wakeup(&sport->port);
276
277 if (uart_circ_empty(xmit))
278 pnx8xxx_stop_tx(&sport->port);
279 }
280
pnx8xxx_int(int irq,void * dev_id)281 static irqreturn_t pnx8xxx_int(int irq, void *dev_id)
282 {
283 struct pnx8xxx_port *sport = dev_id;
284 unsigned int status;
285
286 spin_lock(&sport->port.lock);
287 /* Get the interrupts */
288 status = serial_in(sport, PNX8XXX_ISTAT) & serial_in(sport, PNX8XXX_IEN);
289
290 /* Byte or break signal received */
291 if (status & (PNX8XXX_UART_INT_RX | PNX8XXX_UART_INT_BREAK))
292 pnx8xxx_rx_chars(sport);
293
294 /* TX holding register empty - transmit a byte */
295 if (status & PNX8XXX_UART_INT_TX)
296 pnx8xxx_tx_chars(sport);
297
298 /* Clear the ISTAT register */
299 serial_out(sport, PNX8XXX_ICLR, status);
300
301 spin_unlock(&sport->port.lock);
302 return IRQ_HANDLED;
303 }
304
305 /*
306 * Return TIOCSER_TEMT when transmitter is not busy.
307 */
pnx8xxx_tx_empty(struct uart_port * port)308 static unsigned int pnx8xxx_tx_empty(struct uart_port *port)
309 {
310 struct pnx8xxx_port *sport =
311 container_of(port, struct pnx8xxx_port, port);
312
313 return serial_in(sport, PNX8XXX_FIFO) & PNX8XXX_UART_FIFO_TXFIFO_STA ? 0 : TIOCSER_TEMT;
314 }
315
pnx8xxx_get_mctrl(struct uart_port * port)316 static unsigned int pnx8xxx_get_mctrl(struct uart_port *port)
317 {
318 struct pnx8xxx_port *sport =
319 container_of(port, struct pnx8xxx_port, port);
320 unsigned int mctrl = TIOCM_DSR;
321 unsigned int msr;
322
323 /* REVISIT */
324
325 msr = serial_in(sport, PNX8XXX_MCR);
326
327 mctrl |= msr & PNX8XXX_UART_MCR_CTS ? TIOCM_CTS : 0;
328 mctrl |= msr & PNX8XXX_UART_MCR_DCD ? TIOCM_CAR : 0;
329
330 return mctrl;
331 }
332
pnx8xxx_set_mctrl(struct uart_port * port,unsigned int mctrl)333 static void pnx8xxx_set_mctrl(struct uart_port *port, unsigned int mctrl)
334 {
335 #if 0 /* FIXME */
336 struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
337 unsigned int msr;
338 #endif
339 }
340
341 /*
342 * Interrupts always disabled.
343 */
pnx8xxx_break_ctl(struct uart_port * port,int break_state)344 static void pnx8xxx_break_ctl(struct uart_port *port, int break_state)
345 {
346 struct pnx8xxx_port *sport =
347 container_of(port, struct pnx8xxx_port, port);
348 unsigned long flags;
349 unsigned int lcr;
350
351 spin_lock_irqsave(&sport->port.lock, flags);
352 lcr = serial_in(sport, PNX8XXX_LCR);
353 if (break_state == -1)
354 lcr |= PNX8XXX_UART_LCR_TXBREAK;
355 else
356 lcr &= ~PNX8XXX_UART_LCR_TXBREAK;
357 serial_out(sport, PNX8XXX_LCR, lcr);
358 spin_unlock_irqrestore(&sport->port.lock, flags);
359 }
360
pnx8xxx_startup(struct uart_port * port)361 static int pnx8xxx_startup(struct uart_port *port)
362 {
363 struct pnx8xxx_port *sport =
364 container_of(port, struct pnx8xxx_port, port);
365 int retval;
366
367 /*
368 * Allocate the IRQ
369 */
370 retval = request_irq(sport->port.irq, pnx8xxx_int, 0,
371 "pnx8xxx-uart", sport);
372 if (retval)
373 return retval;
374
375 /*
376 * Finally, clear and enable interrupts
377 */
378
379 serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLRX |
380 PNX8XXX_UART_INT_ALLTX);
381
382 serial_out(sport, PNX8XXX_IEN, serial_in(sport, PNX8XXX_IEN) |
383 PNX8XXX_UART_INT_ALLRX |
384 PNX8XXX_UART_INT_ALLTX);
385
386 /*
387 * Enable modem status interrupts
388 */
389 spin_lock_irq(&sport->port.lock);
390 pnx8xxx_enable_ms(&sport->port);
391 spin_unlock_irq(&sport->port.lock);
392
393 return 0;
394 }
395
pnx8xxx_shutdown(struct uart_port * port)396 static void pnx8xxx_shutdown(struct uart_port *port)
397 {
398 struct pnx8xxx_port *sport =
399 container_of(port, struct pnx8xxx_port, port);
400 int lcr;
401
402 /*
403 * Stop our timer.
404 */
405 del_timer_sync(&sport->timer);
406
407 /*
408 * Disable all interrupts
409 */
410 serial_out(sport, PNX8XXX_IEN, 0);
411
412 /*
413 * Reset the Tx and Rx FIFOS, disable the break condition
414 */
415 lcr = serial_in(sport, PNX8XXX_LCR);
416 lcr &= ~PNX8XXX_UART_LCR_TXBREAK;
417 lcr |= PNX8XXX_UART_LCR_TX_RST | PNX8XXX_UART_LCR_RX_RST;
418 serial_out(sport, PNX8XXX_LCR, lcr);
419
420 /*
421 * Clear all interrupts
422 */
423 serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLRX |
424 PNX8XXX_UART_INT_ALLTX);
425
426 /*
427 * Free the interrupt
428 */
429 free_irq(sport->port.irq, sport);
430 }
431
432 static void
pnx8xxx_set_termios(struct uart_port * port,struct ktermios * termios,struct ktermios * old)433 pnx8xxx_set_termios(struct uart_port *port, struct ktermios *termios,
434 struct ktermios *old)
435 {
436 struct pnx8xxx_port *sport =
437 container_of(port, struct pnx8xxx_port, port);
438 unsigned long flags;
439 unsigned int lcr_fcr, old_ien, baud, quot;
440 unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
441
442 /*
443 * We only support CS7 and CS8.
444 */
445 while ((termios->c_cflag & CSIZE) != CS7 &&
446 (termios->c_cflag & CSIZE) != CS8) {
447 termios->c_cflag &= ~CSIZE;
448 termios->c_cflag |= old_csize;
449 old_csize = CS8;
450 }
451
452 if ((termios->c_cflag & CSIZE) == CS8)
453 lcr_fcr = PNX8XXX_UART_LCR_8BIT;
454 else
455 lcr_fcr = 0;
456
457 if (termios->c_cflag & CSTOPB)
458 lcr_fcr |= PNX8XXX_UART_LCR_2STOPB;
459 if (termios->c_cflag & PARENB) {
460 lcr_fcr |= PNX8XXX_UART_LCR_PAREN;
461 if (!(termios->c_cflag & PARODD))
462 lcr_fcr |= PNX8XXX_UART_LCR_PAREVN;
463 }
464
465 /*
466 * Ask the core to calculate the divisor for us.
467 */
468 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
469 quot = uart_get_divisor(port, baud);
470
471 spin_lock_irqsave(&sport->port.lock, flags);
472
473 sport->port.read_status_mask = ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN) |
474 ISTAT_TO_SM(PNX8XXX_UART_INT_EMPTY) |
475 ISTAT_TO_SM(PNX8XXX_UART_INT_RX);
476 if (termios->c_iflag & INPCK)
477 sport->port.read_status_mask |=
478 FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE) |
479 FIFO_TO_SM(PNX8XXX_UART_FIFO_RXPAR);
480 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
481 sport->port.read_status_mask |=
482 ISTAT_TO_SM(PNX8XXX_UART_INT_BREAK);
483
484 /*
485 * Characters to ignore
486 */
487 sport->port.ignore_status_mask = 0;
488 if (termios->c_iflag & IGNPAR)
489 sport->port.ignore_status_mask |=
490 FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE) |
491 FIFO_TO_SM(PNX8XXX_UART_FIFO_RXPAR);
492 if (termios->c_iflag & IGNBRK) {
493 sport->port.ignore_status_mask |=
494 ISTAT_TO_SM(PNX8XXX_UART_INT_BREAK);
495 /*
496 * If we're ignoring parity and break indicators,
497 * ignore overruns too (for real raw support).
498 */
499 if (termios->c_iflag & IGNPAR)
500 sport->port.ignore_status_mask |=
501 ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN);
502 }
503
504 /*
505 * ignore all characters if CREAD is not set
506 */
507 if ((termios->c_cflag & CREAD) == 0)
508 sport->port.ignore_status_mask |=
509 ISTAT_TO_SM(PNX8XXX_UART_INT_RX);
510
511 del_timer_sync(&sport->timer);
512
513 /*
514 * Update the per-port timeout.
515 */
516 uart_update_timeout(port, termios->c_cflag, baud);
517
518 /*
519 * disable interrupts and drain transmitter
520 */
521 old_ien = serial_in(sport, PNX8XXX_IEN);
522 serial_out(sport, PNX8XXX_IEN, old_ien & ~(PNX8XXX_UART_INT_ALLTX |
523 PNX8XXX_UART_INT_ALLRX));
524
525 while (serial_in(sport, PNX8XXX_FIFO) & PNX8XXX_UART_FIFO_TXFIFO_STA)
526 barrier();
527
528 /* then, disable everything */
529 serial_out(sport, PNX8XXX_IEN, 0);
530
531 /* Reset the Rx and Tx FIFOs too */
532 lcr_fcr |= PNX8XXX_UART_LCR_TX_RST;
533 lcr_fcr |= PNX8XXX_UART_LCR_RX_RST;
534
535 /* set the parity, stop bits and data size */
536 serial_out(sport, PNX8XXX_LCR, lcr_fcr);
537
538 /* set the baud rate */
539 quot -= 1;
540 serial_out(sport, PNX8XXX_BAUD, quot);
541
542 serial_out(sport, PNX8XXX_ICLR, -1);
543
544 serial_out(sport, PNX8XXX_IEN, old_ien);
545
546 if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
547 pnx8xxx_enable_ms(&sport->port);
548
549 spin_unlock_irqrestore(&sport->port.lock, flags);
550 }
551
pnx8xxx_type(struct uart_port * port)552 static const char *pnx8xxx_type(struct uart_port *port)
553 {
554 struct pnx8xxx_port *sport =
555 container_of(port, struct pnx8xxx_port, port);
556
557 return sport->port.type == PORT_PNX8XXX ? "PNX8XXX" : NULL;
558 }
559
560 /*
561 * Release the memory region(s) being used by 'port'.
562 */
pnx8xxx_release_port(struct uart_port * port)563 static void pnx8xxx_release_port(struct uart_port *port)
564 {
565 struct pnx8xxx_port *sport =
566 container_of(port, struct pnx8xxx_port, port);
567
568 release_mem_region(sport->port.mapbase, UART_PORT_SIZE);
569 }
570
571 /*
572 * Request the memory region(s) being used by 'port'.
573 */
pnx8xxx_request_port(struct uart_port * port)574 static int pnx8xxx_request_port(struct uart_port *port)
575 {
576 struct pnx8xxx_port *sport =
577 container_of(port, struct pnx8xxx_port, port);
578 return request_mem_region(sport->port.mapbase, UART_PORT_SIZE,
579 "pnx8xxx-uart") != NULL ? 0 : -EBUSY;
580 }
581
582 /*
583 * Configure/autoconfigure the port.
584 */
pnx8xxx_config_port(struct uart_port * port,int flags)585 static void pnx8xxx_config_port(struct uart_port *port, int flags)
586 {
587 struct pnx8xxx_port *sport =
588 container_of(port, struct pnx8xxx_port, port);
589
590 if (flags & UART_CONFIG_TYPE &&
591 pnx8xxx_request_port(&sport->port) == 0)
592 sport->port.type = PORT_PNX8XXX;
593 }
594
595 /*
596 * Verify the new serial_struct (for TIOCSSERIAL).
597 * The only change we allow are to the flags and type, and
598 * even then only between PORT_PNX8XXX and PORT_UNKNOWN
599 */
600 static int
pnx8xxx_verify_port(struct uart_port * port,struct serial_struct * ser)601 pnx8xxx_verify_port(struct uart_port *port, struct serial_struct *ser)
602 {
603 struct pnx8xxx_port *sport =
604 container_of(port, struct pnx8xxx_port, port);
605 int ret = 0;
606
607 if (ser->type != PORT_UNKNOWN && ser->type != PORT_PNX8XXX)
608 ret = -EINVAL;
609 if (sport->port.irq != ser->irq)
610 ret = -EINVAL;
611 if (ser->io_type != SERIAL_IO_MEM)
612 ret = -EINVAL;
613 if (sport->port.uartclk / 16 != ser->baud_base)
614 ret = -EINVAL;
615 if ((void *)sport->port.mapbase != ser->iomem_base)
616 ret = -EINVAL;
617 if (sport->port.iobase != ser->port)
618 ret = -EINVAL;
619 if (ser->hub6 != 0)
620 ret = -EINVAL;
621 return ret;
622 }
623
624 static const struct uart_ops pnx8xxx_pops = {
625 .tx_empty = pnx8xxx_tx_empty,
626 .set_mctrl = pnx8xxx_set_mctrl,
627 .get_mctrl = pnx8xxx_get_mctrl,
628 .stop_tx = pnx8xxx_stop_tx,
629 .start_tx = pnx8xxx_start_tx,
630 .stop_rx = pnx8xxx_stop_rx,
631 .enable_ms = pnx8xxx_enable_ms,
632 .break_ctl = pnx8xxx_break_ctl,
633 .startup = pnx8xxx_startup,
634 .shutdown = pnx8xxx_shutdown,
635 .set_termios = pnx8xxx_set_termios,
636 .type = pnx8xxx_type,
637 .release_port = pnx8xxx_release_port,
638 .request_port = pnx8xxx_request_port,
639 .config_port = pnx8xxx_config_port,
640 .verify_port = pnx8xxx_verify_port,
641 };
642
643
644 /*
645 * Setup the PNX8XXX serial ports.
646 *
647 * Note also that we support "console=ttySx" where "x" is either 0 or 1.
648 */
pnx8xxx_init_ports(void)649 static void __init pnx8xxx_init_ports(void)
650 {
651 static int first = 1;
652 int i;
653
654 if (!first)
655 return;
656 first = 0;
657
658 for (i = 0; i < NR_PORTS; i++) {
659 timer_setup(&pnx8xxx_ports[i].timer, pnx8xxx_timeout, 0);
660 pnx8xxx_ports[i].port.ops = &pnx8xxx_pops;
661 }
662 }
663
664 #ifdef CONFIG_SERIAL_PNX8XXX_CONSOLE
665
pnx8xxx_console_putchar(struct uart_port * port,int ch)666 static void pnx8xxx_console_putchar(struct uart_port *port, int ch)
667 {
668 struct pnx8xxx_port *sport =
669 container_of(port, struct pnx8xxx_port, port);
670 int status;
671
672 do {
673 /* Wait for UART_TX register to empty */
674 status = serial_in(sport, PNX8XXX_FIFO);
675 } while (status & PNX8XXX_UART_FIFO_TXFIFO);
676 serial_out(sport, PNX8XXX_FIFO, ch);
677 }
678
679 /*
680 * Interrupts are disabled on entering
681 */static void
pnx8xxx_console_write(struct console * co,const char * s,unsigned int count)682 pnx8xxx_console_write(struct console *co, const char *s, unsigned int count)
683 {
684 struct pnx8xxx_port *sport = &pnx8xxx_ports[co->index];
685 unsigned int old_ien, status;
686
687 /*
688 * First, save IEN and then disable interrupts
689 */
690 old_ien = serial_in(sport, PNX8XXX_IEN);
691 serial_out(sport, PNX8XXX_IEN, old_ien & ~(PNX8XXX_UART_INT_ALLTX |
692 PNX8XXX_UART_INT_ALLRX));
693
694 uart_console_write(&sport->port, s, count, pnx8xxx_console_putchar);
695
696 /*
697 * Finally, wait for transmitter to become empty
698 * and restore IEN
699 */
700 do {
701 /* Wait for UART_TX register to empty */
702 status = serial_in(sport, PNX8XXX_FIFO);
703 } while (status & PNX8XXX_UART_FIFO_TXFIFO);
704
705 /* Clear TX and EMPTY interrupt */
706 serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_TX |
707 PNX8XXX_UART_INT_EMPTY);
708
709 serial_out(sport, PNX8XXX_IEN, old_ien);
710 }
711
712 static int __init
pnx8xxx_console_setup(struct console * co,char * options)713 pnx8xxx_console_setup(struct console *co, char *options)
714 {
715 struct pnx8xxx_port *sport;
716 int baud = 38400;
717 int bits = 8;
718 int parity = 'n';
719 int flow = 'n';
720
721 /*
722 * Check whether an invalid uart number has been specified, and
723 * if so, search for the first available port that does have
724 * console support.
725 */
726 if (co->index == -1 || co->index >= NR_PORTS)
727 co->index = 0;
728 sport = &pnx8xxx_ports[co->index];
729
730 if (options)
731 uart_parse_options(options, &baud, &parity, &bits, &flow);
732
733 return uart_set_options(&sport->port, co, baud, parity, bits, flow);
734 }
735
736 static struct uart_driver pnx8xxx_reg;
737 static struct console pnx8xxx_console = {
738 .name = "ttyS",
739 .write = pnx8xxx_console_write,
740 .device = uart_console_device,
741 .setup = pnx8xxx_console_setup,
742 .flags = CON_PRINTBUFFER,
743 .index = -1,
744 .data = &pnx8xxx_reg,
745 };
746
pnx8xxx_rs_console_init(void)747 static int __init pnx8xxx_rs_console_init(void)
748 {
749 pnx8xxx_init_ports();
750 register_console(&pnx8xxx_console);
751 return 0;
752 }
753 console_initcall(pnx8xxx_rs_console_init);
754
755 #define PNX8XXX_CONSOLE &pnx8xxx_console
756 #else
757 #define PNX8XXX_CONSOLE NULL
758 #endif
759
760 static struct uart_driver pnx8xxx_reg = {
761 .owner = THIS_MODULE,
762 .driver_name = "ttyS",
763 .dev_name = "ttyS",
764 .major = SERIAL_PNX8XXX_MAJOR,
765 .minor = MINOR_START,
766 .nr = NR_PORTS,
767 .cons = PNX8XXX_CONSOLE,
768 };
769
pnx8xxx_serial_suspend(struct platform_device * pdev,pm_message_t state)770 static int pnx8xxx_serial_suspend(struct platform_device *pdev, pm_message_t state)
771 {
772 struct pnx8xxx_port *sport = platform_get_drvdata(pdev);
773
774 return uart_suspend_port(&pnx8xxx_reg, &sport->port);
775 }
776
pnx8xxx_serial_resume(struct platform_device * pdev)777 static int pnx8xxx_serial_resume(struct platform_device *pdev)
778 {
779 struct pnx8xxx_port *sport = platform_get_drvdata(pdev);
780
781 return uart_resume_port(&pnx8xxx_reg, &sport->port);
782 }
783
pnx8xxx_serial_probe(struct platform_device * pdev)784 static int pnx8xxx_serial_probe(struct platform_device *pdev)
785 {
786 struct resource *res = pdev->resource;
787 int i;
788
789 for (i = 0; i < pdev->num_resources; i++, res++) {
790 if (!(res->flags & IORESOURCE_MEM))
791 continue;
792
793 for (i = 0; i < NR_PORTS; i++) {
794 if (pnx8xxx_ports[i].port.mapbase != res->start)
795 continue;
796
797 pnx8xxx_ports[i].port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_PNX8XXX_CONSOLE);
798 pnx8xxx_ports[i].port.dev = &pdev->dev;
799 uart_add_one_port(&pnx8xxx_reg, &pnx8xxx_ports[i].port);
800 platform_set_drvdata(pdev, &pnx8xxx_ports[i]);
801 break;
802 }
803 }
804
805 return 0;
806 }
807
pnx8xxx_serial_remove(struct platform_device * pdev)808 static int pnx8xxx_serial_remove(struct platform_device *pdev)
809 {
810 struct pnx8xxx_port *sport = platform_get_drvdata(pdev);
811
812 if (sport)
813 uart_remove_one_port(&pnx8xxx_reg, &sport->port);
814
815 return 0;
816 }
817
818 static struct platform_driver pnx8xxx_serial_driver = {
819 .driver = {
820 .name = "pnx8xxx-uart",
821 },
822 .probe = pnx8xxx_serial_probe,
823 .remove = pnx8xxx_serial_remove,
824 .suspend = pnx8xxx_serial_suspend,
825 .resume = pnx8xxx_serial_resume,
826 };
827
pnx8xxx_serial_init(void)828 static int __init pnx8xxx_serial_init(void)
829 {
830 int ret;
831
832 printk(KERN_INFO "Serial: PNX8XXX driver\n");
833
834 pnx8xxx_init_ports();
835
836 ret = uart_register_driver(&pnx8xxx_reg);
837 if (ret == 0) {
838 ret = platform_driver_register(&pnx8xxx_serial_driver);
839 if (ret)
840 uart_unregister_driver(&pnx8xxx_reg);
841 }
842 return ret;
843 }
844
pnx8xxx_serial_exit(void)845 static void __exit pnx8xxx_serial_exit(void)
846 {
847 platform_driver_unregister(&pnx8xxx_serial_driver);
848 uart_unregister_driver(&pnx8xxx_reg);
849 }
850
851 module_init(pnx8xxx_serial_init);
852 module_exit(pnx8xxx_serial_exit);
853
854 MODULE_AUTHOR("Embedded Alley Solutions, Inc.");
855 MODULE_DESCRIPTION("PNX8XXX SoCs serial port driver");
856 MODULE_LICENSE("GPL");
857 MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_PNX8XXX_MAJOR);
858 MODULE_ALIAS("platform:pnx8xxx-uart");
859