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
serial_in(struct uart_pxa_port * up,int offset)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
serial_out(struct uart_pxa_port * up,int offset,int value)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
serial_pxa_enable_ms(struct uart_port * port)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
serial_pxa_stop_tx(struct uart_port * port)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
serial_pxa_stop_rx(struct uart_port * port)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
receive_chars(struct uart_pxa_port * up,int * status)91 static inline void receive_chars(struct uart_pxa_port *up, int *status)
92 {
93 u8 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
transmit_chars(struct uart_pxa_port * up)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
serial_pxa_start_tx(struct uart_port * port)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 */
check_modem_status(struct uart_pxa_port * up)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 */
serial_pxa_irq(int irq,void * dev_id)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
serial_pxa_tx_empty(struct uart_port * port)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
serial_pxa_get_mctrl(struct uart_port * port)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
serial_pxa_set_mctrl(struct uart_port * port,unsigned int mctrl)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
serial_pxa_break_ctl(struct uart_port * port,int break_state)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
serial_pxa_startup(struct uart_port * port)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
serial_pxa_shutdown(struct uart_port * port)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
serial_pxa_set_termios(struct uart_port * port,struct ktermios * termios,const struct ktermios * old)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
serial_pxa_pm(struct uart_port * port,unsigned int state,unsigned int oldstate)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
serial_pxa_release_port(struct uart_port * port)522 static void serial_pxa_release_port(struct uart_port *port)
523 {
524 }
525
serial_pxa_request_port(struct uart_port * port)526 static int serial_pxa_request_port(struct uart_port *port)
527 {
528 return 0;
529 }
530
serial_pxa_config_port(struct uart_port * port,int flags)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
serial_pxa_verify_port(struct uart_port * port,struct serial_struct * ser)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 *
serial_pxa_type(struct uart_port * port)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 */
wait_for_xmitr(struct uart_pxa_port * up)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
serial_pxa_console_putchar(struct uart_port * port,unsigned char ch)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
serial_pxa_console_write(struct console * co,const char * s,unsigned int count)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
serial_pxa_get_poll_char(struct uart_port * port)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
serial_pxa_put_poll_char(struct uart_port * port,unsigned char c)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
serial_pxa_console_setup(struct console * co,char * options)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
serial_pxa_suspend(struct device * dev)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
serial_pxa_resume(struct device * dev)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
serial_pxa_probe_dt(struct platform_device * pdev,struct uart_pxa_port * sport)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
serial_pxa_probe(struct platform_device * dev)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 */
serial_pxa_init(void)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