xref: /linux/drivers/tty/serial/pxa.c (revision 1fc88e5a2d5358c9a8ae9fc992b75d34ed360339)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  Based on drivers/serial/8250.c by Russell King.
4  *
5  *  Author:	Nicolas Pitre
6  *  Created:	Feb 20, 2003
7  *  Copyright:	(C) 2003 Monta Vista Software, Inc.
8  *
9  * Note 1: This driver is made separate from the already too overloaded
10  * 8250.c because it needs some kirks of its own and that'll make it
11  * easier to add DMA support.
12  *
13  * Note 2: I'm too sick of device allocation policies for serial ports.
14  * If someone else wants to request an "official" allocation of major/minor
15  * for this driver please be my guest.  And don't forget that new hardware
16  * to come from Intel might have more than 3 or 4 of those UARTs.  Let's
17  * hope for a better port registration and dynamic device allocation scheme
18  * with the serial core maintainer satisfaction to appear soon.
19  */
20 
21 
22 #include <linux/ioport.h>
23 #include <linux/init.h>
24 #include <linux/console.h>
25 #include <linux/sysrq.h>
26 #include <linux/serial.h>
27 #include <linux/serial_reg.h>
28 #include <linux/circ_buf.h>
29 #include <linux/delay.h>
30 #include <linux/interrupt.h>
31 #include <linux/of.h>
32 #include <linux/platform_device.h>
33 #include <linux/tty.h>
34 #include <linux/tty_flip.h>
35 #include <linux/serial_core.h>
36 #include <linux/clk.h>
37 #include <linux/io.h>
38 #include <linux/slab.h>
39 
40 #define PXA_NAME_LEN		8
41 
42 struct uart_pxa_port {
43 	struct uart_port        port;
44 	unsigned char           ier;
45 	unsigned char           lcr;
46 	unsigned char           mcr;
47 	unsigned int            lsr_break_flag;
48 	struct clk		*clk;
49 	char			name[PXA_NAME_LEN];
50 };
51 
52 static inline unsigned int serial_in(struct uart_pxa_port *up, int offset)
53 {
54 	offset <<= 2;
55 	return readl(up->port.membase + offset);
56 }
57 
58 static inline void serial_out(struct uart_pxa_port *up, int offset, int value)
59 {
60 	offset <<= 2;
61 	writel(value, up->port.membase + offset);
62 }
63 
64 static void serial_pxa_enable_ms(struct uart_port *port)
65 {
66 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
67 
68 	up->ier |= UART_IER_MSI;
69 	serial_out(up, UART_IER, up->ier);
70 }
71 
72 static void serial_pxa_stop_tx(struct uart_port *port)
73 {
74 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
75 
76 	if (up->ier & UART_IER_THRI) {
77 		up->ier &= ~UART_IER_THRI;
78 		serial_out(up, UART_IER, up->ier);
79 	}
80 }
81 
82 static void serial_pxa_stop_rx(struct uart_port *port)
83 {
84 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
85 
86 	up->ier &= ~UART_IER_RLSI;
87 	up->port.read_status_mask &= ~UART_LSR_DR;
88 	serial_out(up, UART_IER, up->ier);
89 }
90 
91 static inline void receive_chars(struct uart_pxa_port *up, int *status)
92 {
93 	unsigned int ch, flag;
94 	int max_count = 256;
95 
96 	do {
97 		/* work around Errata #20 according to
98 		 * Intel(R) PXA27x Processor Family
99 		 * Specification Update (May 2005)
100 		 *
101 		 * Step 2
102 		 * Disable the Reciever Time Out Interrupt via IER[RTOEI]
103 		 */
104 		up->ier &= ~UART_IER_RTOIE;
105 		serial_out(up, UART_IER, up->ier);
106 
107 		ch = serial_in(up, UART_RX);
108 		flag = TTY_NORMAL;
109 		up->port.icount.rx++;
110 
111 		if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
112 				       UART_LSR_FE | UART_LSR_OE))) {
113 			/*
114 			 * For statistics only
115 			 */
116 			if (*status & UART_LSR_BI) {
117 				*status &= ~(UART_LSR_FE | UART_LSR_PE);
118 				up->port.icount.brk++;
119 				/*
120 				 * We do the SysRQ and SAK checking
121 				 * here because otherwise the break
122 				 * may get masked by ignore_status_mask
123 				 * or read_status_mask.
124 				 */
125 				if (uart_handle_break(&up->port))
126 					goto ignore_char;
127 			} else if (*status & UART_LSR_PE)
128 				up->port.icount.parity++;
129 			else if (*status & UART_LSR_FE)
130 				up->port.icount.frame++;
131 			if (*status & UART_LSR_OE)
132 				up->port.icount.overrun++;
133 
134 			/*
135 			 * Mask off conditions which should be ignored.
136 			 */
137 			*status &= up->port.read_status_mask;
138 
139 #ifdef CONFIG_SERIAL_PXA_CONSOLE
140 			if (up->port.line == up->port.cons->index) {
141 				/* Recover the break flag from console xmit */
142 				*status |= up->lsr_break_flag;
143 				up->lsr_break_flag = 0;
144 			}
145 #endif
146 			if (*status & UART_LSR_BI) {
147 				flag = TTY_BREAK;
148 			} else if (*status & UART_LSR_PE)
149 				flag = TTY_PARITY;
150 			else if (*status & UART_LSR_FE)
151 				flag = TTY_FRAME;
152 		}
153 
154 		if (uart_handle_sysrq_char(&up->port, ch))
155 			goto ignore_char;
156 
157 		uart_insert_char(&up->port, *status, UART_LSR_OE, ch, flag);
158 
159 	ignore_char:
160 		*status = serial_in(up, UART_LSR);
161 	} while ((*status & UART_LSR_DR) && (max_count-- > 0));
162 	tty_flip_buffer_push(&up->port.state->port);
163 
164 	/* work around Errata #20 according to
165 	 * Intel(R) PXA27x Processor Family
166 	 * Specification Update (May 2005)
167 	 *
168 	 * Step 6:
169 	 * No more data in FIFO: Re-enable RTO interrupt via IER[RTOIE]
170 	 */
171 	up->ier |= UART_IER_RTOIE;
172 	serial_out(up, UART_IER, up->ier);
173 }
174 
175 static void transmit_chars(struct uart_pxa_port *up)
176 {
177 	u8 ch;
178 
179 	uart_port_tx_limited(&up->port, ch, up->port.fifosize / 2,
180 		true,
181 		serial_out(up, UART_TX, ch),
182 		({}));
183 }
184 
185 static void serial_pxa_start_tx(struct uart_port *port)
186 {
187 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
188 
189 	if (!(up->ier & UART_IER_THRI)) {
190 		up->ier |= UART_IER_THRI;
191 		serial_out(up, UART_IER, up->ier);
192 	}
193 }
194 
195 /* should hold up->port.lock */
196 static inline void check_modem_status(struct uart_pxa_port *up)
197 {
198 	int status;
199 
200 	status = serial_in(up, UART_MSR);
201 
202 	if ((status & UART_MSR_ANY_DELTA) == 0)
203 		return;
204 
205 	if (status & UART_MSR_TERI)
206 		up->port.icount.rng++;
207 	if (status & UART_MSR_DDSR)
208 		up->port.icount.dsr++;
209 	if (status & UART_MSR_DDCD)
210 		uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
211 	if (status & UART_MSR_DCTS)
212 		uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
213 
214 	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
215 }
216 
217 /*
218  * This handles the interrupt from one port.
219  */
220 static inline irqreturn_t serial_pxa_irq(int irq, void *dev_id)
221 {
222 	struct uart_pxa_port *up = dev_id;
223 	unsigned int iir, lsr;
224 
225 	iir = serial_in(up, UART_IIR);
226 	if (iir & UART_IIR_NO_INT)
227 		return IRQ_NONE;
228 	spin_lock(&up->port.lock);
229 	lsr = serial_in(up, UART_LSR);
230 	if (lsr & UART_LSR_DR)
231 		receive_chars(up, &lsr);
232 	check_modem_status(up);
233 	if (lsr & UART_LSR_THRE)
234 		transmit_chars(up);
235 	spin_unlock(&up->port.lock);
236 	return IRQ_HANDLED;
237 }
238 
239 static unsigned int serial_pxa_tx_empty(struct uart_port *port)
240 {
241 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
242 	unsigned long flags;
243 	unsigned int ret;
244 
245 	spin_lock_irqsave(&up->port.lock, flags);
246 	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
247 	spin_unlock_irqrestore(&up->port.lock, flags);
248 
249 	return ret;
250 }
251 
252 static unsigned int serial_pxa_get_mctrl(struct uart_port *port)
253 {
254 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
255 	unsigned char status;
256 	unsigned int ret;
257 
258 	status = serial_in(up, UART_MSR);
259 
260 	ret = 0;
261 	if (status & UART_MSR_DCD)
262 		ret |= TIOCM_CAR;
263 	if (status & UART_MSR_RI)
264 		ret |= TIOCM_RNG;
265 	if (status & UART_MSR_DSR)
266 		ret |= TIOCM_DSR;
267 	if (status & UART_MSR_CTS)
268 		ret |= TIOCM_CTS;
269 	return ret;
270 }
271 
272 static void serial_pxa_set_mctrl(struct uart_port *port, unsigned int mctrl)
273 {
274 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
275 	unsigned char mcr = 0;
276 
277 	if (mctrl & TIOCM_RTS)
278 		mcr |= UART_MCR_RTS;
279 	if (mctrl & TIOCM_DTR)
280 		mcr |= UART_MCR_DTR;
281 	if (mctrl & TIOCM_OUT1)
282 		mcr |= UART_MCR_OUT1;
283 	if (mctrl & TIOCM_OUT2)
284 		mcr |= UART_MCR_OUT2;
285 	if (mctrl & TIOCM_LOOP)
286 		mcr |= UART_MCR_LOOP;
287 
288 	mcr |= up->mcr;
289 
290 	serial_out(up, UART_MCR, mcr);
291 }
292 
293 static void serial_pxa_break_ctl(struct uart_port *port, int break_state)
294 {
295 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
296 	unsigned long flags;
297 
298 	spin_lock_irqsave(&up->port.lock, flags);
299 	if (break_state == -1)
300 		up->lcr |= UART_LCR_SBC;
301 	else
302 		up->lcr &= ~UART_LCR_SBC;
303 	serial_out(up, UART_LCR, up->lcr);
304 	spin_unlock_irqrestore(&up->port.lock, flags);
305 }
306 
307 static int serial_pxa_startup(struct uart_port *port)
308 {
309 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
310 	unsigned long flags;
311 	int retval;
312 
313 	if (port->line == 3) /* HWUART */
314 		up->mcr |= UART_MCR_AFE;
315 	else
316 		up->mcr = 0;
317 
318 	up->port.uartclk = clk_get_rate(up->clk);
319 
320 	/*
321 	 * Allocate the IRQ
322 	 */
323 	retval = request_irq(up->port.irq, serial_pxa_irq, 0, up->name, up);
324 	if (retval)
325 		return retval;
326 
327 	/*
328 	 * Clear the FIFO buffers and disable them.
329 	 * (they will be reenabled in set_termios())
330 	 */
331 	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
332 	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
333 			UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
334 	serial_out(up, UART_FCR, 0);
335 
336 	/*
337 	 * Clear the interrupt registers.
338 	 */
339 	(void) serial_in(up, UART_LSR);
340 	(void) serial_in(up, UART_RX);
341 	(void) serial_in(up, UART_IIR);
342 	(void) serial_in(up, UART_MSR);
343 
344 	/*
345 	 * Now, initialize the UART
346 	 */
347 	serial_out(up, UART_LCR, UART_LCR_WLEN8);
348 
349 	spin_lock_irqsave(&up->port.lock, flags);
350 	up->port.mctrl |= TIOCM_OUT2;
351 	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
352 	spin_unlock_irqrestore(&up->port.lock, flags);
353 
354 	/*
355 	 * Finally, enable interrupts.  Note: Modem status interrupts
356 	 * are set via set_termios(), which will be occurring imminently
357 	 * anyway, so we don't enable them here.
358 	 */
359 	up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE | UART_IER_UUE;
360 	serial_out(up, UART_IER, up->ier);
361 
362 	/*
363 	 * And clear the interrupt registers again for luck.
364 	 */
365 	(void) serial_in(up, UART_LSR);
366 	(void) serial_in(up, UART_RX);
367 	(void) serial_in(up, UART_IIR);
368 	(void) serial_in(up, UART_MSR);
369 
370 	return 0;
371 }
372 
373 static void serial_pxa_shutdown(struct uart_port *port)
374 {
375 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
376 	unsigned long flags;
377 
378 	free_irq(up->port.irq, up);
379 
380 	/*
381 	 * Disable interrupts from this port
382 	 */
383 	up->ier = 0;
384 	serial_out(up, UART_IER, 0);
385 
386 	spin_lock_irqsave(&up->port.lock, flags);
387 	up->port.mctrl &= ~TIOCM_OUT2;
388 	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
389 	spin_unlock_irqrestore(&up->port.lock, flags);
390 
391 	/*
392 	 * Disable break condition and FIFOs
393 	 */
394 	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
395 	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
396 				  UART_FCR_CLEAR_RCVR |
397 				  UART_FCR_CLEAR_XMIT);
398 	serial_out(up, UART_FCR, 0);
399 }
400 
401 static void
402 serial_pxa_set_termios(struct uart_port *port, struct ktermios *termios,
403 		       const struct ktermios *old)
404 {
405 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
406 	unsigned char cval, fcr = 0;
407 	unsigned long flags;
408 	unsigned int baud, quot;
409 	unsigned int dll;
410 
411 	cval = UART_LCR_WLEN(tty_get_char_size(termios->c_cflag));
412 
413 	if (termios->c_cflag & CSTOPB)
414 		cval |= UART_LCR_STOP;
415 	if (termios->c_cflag & PARENB)
416 		cval |= UART_LCR_PARITY;
417 	if (!(termios->c_cflag & PARODD))
418 		cval |= UART_LCR_EPAR;
419 
420 	/*
421 	 * Ask the core to calculate the divisor for us.
422 	 */
423 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
424 	quot = uart_get_divisor(port, baud);
425 
426 	if ((up->port.uartclk / quot) < (2400 * 16))
427 		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR1;
428 	else if ((up->port.uartclk / quot) < (230400 * 16))
429 		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR8;
430 	else
431 		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR32;
432 
433 	/*
434 	 * Ok, we're now changing the port state.  Do it with
435 	 * interrupts disabled.
436 	 */
437 	spin_lock_irqsave(&up->port.lock, flags);
438 
439 	/*
440 	 * Ensure the port will be enabled.
441 	 * This is required especially for serial console.
442 	 */
443 	up->ier |= UART_IER_UUE;
444 
445 	/*
446 	 * Update the per-port timeout.
447 	 */
448 	uart_update_timeout(port, termios->c_cflag, baud);
449 
450 	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
451 	if (termios->c_iflag & INPCK)
452 		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
453 	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
454 		up->port.read_status_mask |= UART_LSR_BI;
455 
456 	/*
457 	 * Characters to ignore
458 	 */
459 	up->port.ignore_status_mask = 0;
460 	if (termios->c_iflag & IGNPAR)
461 		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
462 	if (termios->c_iflag & IGNBRK) {
463 		up->port.ignore_status_mask |= UART_LSR_BI;
464 		/*
465 		 * If we're ignoring parity and break indicators,
466 		 * ignore overruns too (for real raw support).
467 		 */
468 		if (termios->c_iflag & IGNPAR)
469 			up->port.ignore_status_mask |= UART_LSR_OE;
470 	}
471 
472 	/*
473 	 * ignore all characters if CREAD is not set
474 	 */
475 	if ((termios->c_cflag & CREAD) == 0)
476 		up->port.ignore_status_mask |= UART_LSR_DR;
477 
478 	/*
479 	 * CTS flow control flag and modem status interrupts
480 	 */
481 	up->ier &= ~UART_IER_MSI;
482 	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
483 		up->ier |= UART_IER_MSI;
484 
485 	serial_out(up, UART_IER, up->ier);
486 
487 	if (termios->c_cflag & CRTSCTS)
488 		up->mcr |= UART_MCR_AFE;
489 	else
490 		up->mcr &= ~UART_MCR_AFE;
491 
492 	serial_out(up, UART_LCR, cval | UART_LCR_DLAB);	/* set DLAB */
493 	serial_out(up, UART_DLL, quot & 0xff);		/* LS of divisor */
494 
495 	/*
496 	 * work around Errata #75 according to Intel(R) PXA27x Processor Family
497 	 * Specification Update (Nov 2005)
498 	 */
499 	dll = serial_in(up, UART_DLL);
500 	WARN_ON(dll != (quot & 0xff));
501 
502 	serial_out(up, UART_DLM, quot >> 8);		/* MS of divisor */
503 	serial_out(up, UART_LCR, cval);			/* reset DLAB */
504 	up->lcr = cval;					/* Save LCR */
505 	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
506 	serial_out(up, UART_FCR, fcr);
507 	spin_unlock_irqrestore(&up->port.lock, flags);
508 }
509 
510 static void
511 serial_pxa_pm(struct uart_port *port, unsigned int state,
512 	      unsigned int oldstate)
513 {
514 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
515 
516 	if (!state)
517 		clk_prepare_enable(up->clk);
518 	else
519 		clk_disable_unprepare(up->clk);
520 }
521 
522 static void serial_pxa_release_port(struct uart_port *port)
523 {
524 }
525 
526 static int serial_pxa_request_port(struct uart_port *port)
527 {
528 	return 0;
529 }
530 
531 static void serial_pxa_config_port(struct uart_port *port, int flags)
532 {
533 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
534 	up->port.type = PORT_PXA;
535 }
536 
537 static int
538 serial_pxa_verify_port(struct uart_port *port, struct serial_struct *ser)
539 {
540 	/* we don't want the core code to modify any port params */
541 	return -EINVAL;
542 }
543 
544 static const char *
545 serial_pxa_type(struct uart_port *port)
546 {
547 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
548 	return up->name;
549 }
550 
551 static struct uart_pxa_port *serial_pxa_ports[4];
552 static struct uart_driver serial_pxa_reg;
553 
554 #ifdef CONFIG_SERIAL_PXA_CONSOLE
555 
556 /*
557  *	Wait for transmitter & holding register to empty
558  */
559 static void wait_for_xmitr(struct uart_pxa_port *up)
560 {
561 	unsigned int status, tmout = 10000;
562 
563 	/* Wait up to 10ms for the character(s) to be sent. */
564 	do {
565 		status = serial_in(up, UART_LSR);
566 
567 		if (status & UART_LSR_BI)
568 			up->lsr_break_flag = UART_LSR_BI;
569 
570 		if (--tmout == 0)
571 			break;
572 		udelay(1);
573 	} while (!uart_lsr_tx_empty(status));
574 
575 	/* Wait up to 1s for flow control if necessary */
576 	if (up->port.flags & UPF_CONS_FLOW) {
577 		tmout = 1000000;
578 		while (--tmout &&
579 		       ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
580 			udelay(1);
581 	}
582 }
583 
584 static void serial_pxa_console_putchar(struct uart_port *port, unsigned char ch)
585 {
586 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
587 
588 	wait_for_xmitr(up);
589 	serial_out(up, UART_TX, ch);
590 }
591 
592 /*
593  * Print a string to the serial port trying not to disturb
594  * any possible real use of the port...
595  *
596  *	The console_lock must be held when we get here.
597  */
598 static void
599 serial_pxa_console_write(struct console *co, const char *s, unsigned int count)
600 {
601 	struct uart_pxa_port *up = serial_pxa_ports[co->index];
602 	unsigned int ier;
603 	unsigned long flags;
604 	int locked = 1;
605 
606 	clk_enable(up->clk);
607 	local_irq_save(flags);
608 	if (up->port.sysrq)
609 		locked = 0;
610 	else if (oops_in_progress)
611 		locked = spin_trylock(&up->port.lock);
612 	else
613 		spin_lock(&up->port.lock);
614 
615 	/*
616 	 *	First save the IER then disable the interrupts
617 	 */
618 	ier = serial_in(up, UART_IER);
619 	serial_out(up, UART_IER, UART_IER_UUE);
620 
621 	uart_console_write(&up->port, s, count, serial_pxa_console_putchar);
622 
623 	/*
624 	 *	Finally, wait for transmitter to become empty
625 	 *	and restore the IER
626 	 */
627 	wait_for_xmitr(up);
628 	serial_out(up, UART_IER, ier);
629 
630 	if (locked)
631 		spin_unlock(&up->port.lock);
632 	local_irq_restore(flags);
633 	clk_disable(up->clk);
634 
635 }
636 
637 #ifdef CONFIG_CONSOLE_POLL
638 /*
639  * Console polling routines for writing and reading from the uart while
640  * in an interrupt or debug context.
641  */
642 
643 static int serial_pxa_get_poll_char(struct uart_port *port)
644 {
645 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
646 	unsigned char lsr = serial_in(up, UART_LSR);
647 
648 	while (!(lsr & UART_LSR_DR))
649 		lsr = serial_in(up, UART_LSR);
650 
651 	return serial_in(up, UART_RX);
652 }
653 
654 
655 static void serial_pxa_put_poll_char(struct uart_port *port,
656 			 unsigned char c)
657 {
658 	unsigned int ier;
659 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
660 
661 	/*
662 	 *	First save the IER then disable the interrupts
663 	 */
664 	ier = serial_in(up, UART_IER);
665 	serial_out(up, UART_IER, UART_IER_UUE);
666 
667 	wait_for_xmitr(up);
668 	/*
669 	 *	Send the character out.
670 	 */
671 	serial_out(up, UART_TX, c);
672 
673 	/*
674 	 *	Finally, wait for transmitter to become empty
675 	 *	and restore the IER
676 	 */
677 	wait_for_xmitr(up);
678 	serial_out(up, UART_IER, ier);
679 }
680 
681 #endif /* CONFIG_CONSOLE_POLL */
682 
683 static int __init
684 serial_pxa_console_setup(struct console *co, char *options)
685 {
686 	struct uart_pxa_port *up;
687 	int baud = 9600;
688 	int bits = 8;
689 	int parity = 'n';
690 	int flow = 'n';
691 
692 	if (co->index == -1 || co->index >= serial_pxa_reg.nr)
693 		co->index = 0;
694 	up = serial_pxa_ports[co->index];
695 	if (!up)
696 		return -ENODEV;
697 
698 	if (options)
699 		uart_parse_options(options, &baud, &parity, &bits, &flow);
700 
701 	return uart_set_options(&up->port, co, baud, parity, bits, flow);
702 }
703 
704 static struct console serial_pxa_console = {
705 	.name		= "ttyS",
706 	.write		= serial_pxa_console_write,
707 	.device		= uart_console_device,
708 	.setup		= serial_pxa_console_setup,
709 	.flags		= CON_PRINTBUFFER,
710 	.index		= -1,
711 	.data		= &serial_pxa_reg,
712 };
713 
714 #define PXA_CONSOLE	&serial_pxa_console
715 #else
716 #define PXA_CONSOLE	NULL
717 #endif
718 
719 static const struct uart_ops serial_pxa_pops = {
720 	.tx_empty	= serial_pxa_tx_empty,
721 	.set_mctrl	= serial_pxa_set_mctrl,
722 	.get_mctrl	= serial_pxa_get_mctrl,
723 	.stop_tx	= serial_pxa_stop_tx,
724 	.start_tx	= serial_pxa_start_tx,
725 	.stop_rx	= serial_pxa_stop_rx,
726 	.enable_ms	= serial_pxa_enable_ms,
727 	.break_ctl	= serial_pxa_break_ctl,
728 	.startup	= serial_pxa_startup,
729 	.shutdown	= serial_pxa_shutdown,
730 	.set_termios	= serial_pxa_set_termios,
731 	.pm		= serial_pxa_pm,
732 	.type		= serial_pxa_type,
733 	.release_port	= serial_pxa_release_port,
734 	.request_port	= serial_pxa_request_port,
735 	.config_port	= serial_pxa_config_port,
736 	.verify_port	= serial_pxa_verify_port,
737 #if defined(CONFIG_CONSOLE_POLL) && defined(CONFIG_SERIAL_PXA_CONSOLE)
738 	.poll_get_char = serial_pxa_get_poll_char,
739 	.poll_put_char = serial_pxa_put_poll_char,
740 #endif
741 };
742 
743 static struct uart_driver serial_pxa_reg = {
744 	.owner		= THIS_MODULE,
745 	.driver_name	= "PXA serial",
746 	.dev_name	= "ttyS",
747 	.major		= TTY_MAJOR,
748 	.minor		= 64,
749 	.nr		= 4,
750 	.cons		= PXA_CONSOLE,
751 };
752 
753 #ifdef CONFIG_PM
754 static int serial_pxa_suspend(struct device *dev)
755 {
756         struct uart_pxa_port *sport = dev_get_drvdata(dev);
757 
758         if (sport)
759                 uart_suspend_port(&serial_pxa_reg, &sport->port);
760 
761         return 0;
762 }
763 
764 static int serial_pxa_resume(struct device *dev)
765 {
766         struct uart_pxa_port *sport = dev_get_drvdata(dev);
767 
768         if (sport)
769                 uart_resume_port(&serial_pxa_reg, &sport->port);
770 
771         return 0;
772 }
773 
774 static const struct dev_pm_ops serial_pxa_pm_ops = {
775 	.suspend	= serial_pxa_suspend,
776 	.resume		= serial_pxa_resume,
777 };
778 #endif
779 
780 static const struct of_device_id serial_pxa_dt_ids[] = {
781 	{ .compatible = "mrvl,pxa-uart", },
782 	{ .compatible = "mrvl,mmp-uart", },
783 	{}
784 };
785 
786 static int serial_pxa_probe_dt(struct platform_device *pdev,
787 			       struct uart_pxa_port *sport)
788 {
789 	struct device_node *np = pdev->dev.of_node;
790 	int ret;
791 
792 	if (!np)
793 		return 1;
794 
795 	ret = of_alias_get_id(np, "serial");
796 	if (ret < 0) {
797 		dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
798 		return ret;
799 	}
800 	sport->port.line = ret;
801 	return 0;
802 }
803 
804 static int serial_pxa_probe(struct platform_device *dev)
805 {
806 	struct uart_pxa_port *sport;
807 	struct resource *mmres;
808 	int ret;
809 	int irq;
810 
811 	mmres = platform_get_resource(dev, IORESOURCE_MEM, 0);
812 	if (!mmres)
813 		return -ENODEV;
814 
815 	irq = platform_get_irq(dev, 0);
816 	if (irq < 0)
817 		return irq;
818 
819 	sport = kzalloc(sizeof(struct uart_pxa_port), GFP_KERNEL);
820 	if (!sport)
821 		return -ENOMEM;
822 
823 	sport->clk = clk_get(&dev->dev, NULL);
824 	if (IS_ERR(sport->clk)) {
825 		ret = PTR_ERR(sport->clk);
826 		goto err_free;
827 	}
828 
829 	ret = clk_prepare(sport->clk);
830 	if (ret) {
831 		clk_put(sport->clk);
832 		goto err_free;
833 	}
834 
835 	sport->port.type = PORT_PXA;
836 	sport->port.iotype = UPIO_MEM;
837 	sport->port.mapbase = mmres->start;
838 	sport->port.irq = irq;
839 	sport->port.fifosize = 64;
840 	sport->port.ops = &serial_pxa_pops;
841 	sport->port.dev = &dev->dev;
842 	sport->port.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF;
843 	sport->port.uartclk = clk_get_rate(sport->clk);
844 	sport->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_PXA_CONSOLE);
845 
846 	ret = serial_pxa_probe_dt(dev, sport);
847 	if (ret > 0)
848 		sport->port.line = dev->id;
849 	else if (ret < 0)
850 		goto err_clk;
851 	if (sport->port.line >= ARRAY_SIZE(serial_pxa_ports)) {
852 		dev_err(&dev->dev, "serial%d out of range\n", sport->port.line);
853 		ret = -EINVAL;
854 		goto err_clk;
855 	}
856 	snprintf(sport->name, PXA_NAME_LEN - 1, "UART%d", sport->port.line + 1);
857 
858 	sport->port.membase = ioremap(mmres->start, resource_size(mmres));
859 	if (!sport->port.membase) {
860 		ret = -ENOMEM;
861 		goto err_clk;
862 	}
863 
864 	serial_pxa_ports[sport->port.line] = sport;
865 
866 	uart_add_one_port(&serial_pxa_reg, &sport->port);
867 	platform_set_drvdata(dev, sport);
868 
869 	return 0;
870 
871  err_clk:
872 	clk_unprepare(sport->clk);
873 	clk_put(sport->clk);
874  err_free:
875 	kfree(sport);
876 	return ret;
877 }
878 
879 static struct platform_driver serial_pxa_driver = {
880         .probe          = serial_pxa_probe,
881 
882 	.driver		= {
883 	        .name	= "pxa2xx-uart",
884 #ifdef CONFIG_PM
885 		.pm	= &serial_pxa_pm_ops,
886 #endif
887 		.suppress_bind_attrs = true,
888 		.of_match_table = serial_pxa_dt_ids,
889 	},
890 };
891 
892 
893 /* 8250 driver for PXA serial ports should be used */
894 static int __init serial_pxa_init(void)
895 {
896 	int ret;
897 
898 	ret = uart_register_driver(&serial_pxa_reg);
899 	if (ret != 0)
900 		return ret;
901 
902 	ret = platform_driver_register(&serial_pxa_driver);
903 	if (ret != 0)
904 		uart_unregister_driver(&serial_pxa_reg);
905 
906 	return ret;
907 }
908 device_initcall(serial_pxa_init);
909