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v3.1
  1/*
  2 *  Based on drivers/serial/8250.c by Russell King.
  3 *
  4 *  Author:	Nicolas Pitre
  5 *  Created:	Feb 20, 2003
  6 *  Copyright:	(C) 2003 Monta Vista Software, Inc.
  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 * Note 1: This driver is made separate from the already too overloaded
 14 * 8250.c because it needs some kirks of its own and that'll make it
 15 * easier to add DMA support.
 16 *
 17 * Note 2: I'm too sick of device allocation policies for serial ports.
 18 * If someone else wants to request an "official" allocation of major/minor
 19 * for this driver please be my guest.  And don't forget that new hardware
 20 * to come from Intel might have more than 3 or 4 of those UARTs.  Let's
 21 * hope for a better port registration and dynamic device allocation scheme
 22 * with the serial core maintainer satisfaction to appear soon.
 23 */
 24
 25
 26#if defined(CONFIG_SERIAL_PXA_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
 27#define SUPPORT_SYSRQ
 28#endif
 29
 30#include <linux/module.h>
 31#include <linux/ioport.h>
 32#include <linux/init.h>
 33#include <linux/console.h>
 34#include <linux/sysrq.h>
 35#include <linux/serial_reg.h>
 36#include <linux/circ_buf.h>
 37#include <linux/delay.h>
 38#include <linux/interrupt.h>
 
 39#include <linux/platform_device.h>
 40#include <linux/tty.h>
 41#include <linux/tty_flip.h>
 42#include <linux/serial_core.h>
 43#include <linux/clk.h>
 44#include <linux/io.h>
 45#include <linux/slab.h>
 46
 
 
 47struct uart_pxa_port {
 48	struct uart_port        port;
 49	unsigned char           ier;
 50	unsigned char           lcr;
 51	unsigned char           mcr;
 52	unsigned int            lsr_break_flag;
 53	struct clk		*clk;
 54	char			*name;
 55};
 56
 57static inline unsigned int serial_in(struct uart_pxa_port *up, int offset)
 58{
 59	offset <<= 2;
 60	return readl(up->port.membase + offset);
 61}
 62
 63static inline void serial_out(struct uart_pxa_port *up, int offset, int value)
 64{
 65	offset <<= 2;
 66	writel(value, up->port.membase + offset);
 67}
 68
 69static void serial_pxa_enable_ms(struct uart_port *port)
 70{
 71	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
 72
 73	up->ier |= UART_IER_MSI;
 74	serial_out(up, UART_IER, up->ier);
 75}
 76
 77static void serial_pxa_stop_tx(struct uart_port *port)
 78{
 79	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
 80
 81	if (up->ier & UART_IER_THRI) {
 82		up->ier &= ~UART_IER_THRI;
 83		serial_out(up, UART_IER, up->ier);
 84	}
 85}
 86
 87static void serial_pxa_stop_rx(struct uart_port *port)
 88{
 89	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
 90
 91	up->ier &= ~UART_IER_RLSI;
 92	up->port.read_status_mask &= ~UART_LSR_DR;
 93	serial_out(up, UART_IER, up->ier);
 94}
 95
 96static inline void receive_chars(struct uart_pxa_port *up, int *status)
 97{
 98	struct tty_struct *tty = up->port.state->port.tty;
 99	unsigned int ch, flag;
100	int max_count = 256;
101
102	do {
 
 
 
 
 
 
 
 
 
 
103		ch = serial_in(up, UART_RX);
104		flag = TTY_NORMAL;
105		up->port.icount.rx++;
106
107		if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
108				       UART_LSR_FE | UART_LSR_OE))) {
109			/*
110			 * For statistics only
111			 */
112			if (*status & UART_LSR_BI) {
113				*status &= ~(UART_LSR_FE | UART_LSR_PE);
114				up->port.icount.brk++;
115				/*
116				 * We do the SysRQ and SAK checking
117				 * here because otherwise the break
118				 * may get masked by ignore_status_mask
119				 * or read_status_mask.
120				 */
121				if (uart_handle_break(&up->port))
122					goto ignore_char;
123			} else if (*status & UART_LSR_PE)
124				up->port.icount.parity++;
125			else if (*status & UART_LSR_FE)
126				up->port.icount.frame++;
127			if (*status & UART_LSR_OE)
128				up->port.icount.overrun++;
129
130			/*
131			 * Mask off conditions which should be ignored.
132			 */
133			*status &= up->port.read_status_mask;
134
135#ifdef CONFIG_SERIAL_PXA_CONSOLE
136			if (up->port.line == up->port.cons->index) {
137				/* Recover the break flag from console xmit */
138				*status |= up->lsr_break_flag;
139				up->lsr_break_flag = 0;
140			}
141#endif
142			if (*status & UART_LSR_BI) {
143				flag = TTY_BREAK;
144			} else if (*status & UART_LSR_PE)
145				flag = TTY_PARITY;
146			else if (*status & UART_LSR_FE)
147				flag = TTY_FRAME;
148		}
149
150		if (uart_handle_sysrq_char(&up->port, ch))
151			goto ignore_char;
152
153		uart_insert_char(&up->port, *status, UART_LSR_OE, ch, flag);
154
155	ignore_char:
156		*status = serial_in(up, UART_LSR);
157	} while ((*status & UART_LSR_DR) && (max_count-- > 0));
158	tty_flip_buffer_push(tty);
 
 
 
 
 
 
 
 
 
 
159}
160
161static void transmit_chars(struct uart_pxa_port *up)
162{
163	struct circ_buf *xmit = &up->port.state->xmit;
164	int count;
165
166	if (up->port.x_char) {
167		serial_out(up, UART_TX, up->port.x_char);
168		up->port.icount.tx++;
169		up->port.x_char = 0;
170		return;
171	}
172	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
173		serial_pxa_stop_tx(&up->port);
174		return;
175	}
176
177	count = up->port.fifosize / 2;
178	do {
179		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
180		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
181		up->port.icount.tx++;
182		if (uart_circ_empty(xmit))
183			break;
184	} while (--count > 0);
185
186	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
187		uart_write_wakeup(&up->port);
188
189
190	if (uart_circ_empty(xmit))
191		serial_pxa_stop_tx(&up->port);
192}
193
194static void serial_pxa_start_tx(struct uart_port *port)
195{
196	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
197
198	if (!(up->ier & UART_IER_THRI)) {
199		up->ier |= UART_IER_THRI;
200		serial_out(up, UART_IER, up->ier);
201	}
202}
203
 
204static inline void check_modem_status(struct uart_pxa_port *up)
205{
206	int status;
207
208	status = serial_in(up, UART_MSR);
209
210	if ((status & UART_MSR_ANY_DELTA) == 0)
211		return;
212
213	if (status & UART_MSR_TERI)
214		up->port.icount.rng++;
215	if (status & UART_MSR_DDSR)
216		up->port.icount.dsr++;
217	if (status & UART_MSR_DDCD)
218		uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
219	if (status & UART_MSR_DCTS)
220		uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
221
222	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
223}
224
225/*
226 * This handles the interrupt from one port.
227 */
228static inline irqreturn_t serial_pxa_irq(int irq, void *dev_id)
229{
230	struct uart_pxa_port *up = dev_id;
231	unsigned int iir, lsr;
232
233	iir = serial_in(up, UART_IIR);
234	if (iir & UART_IIR_NO_INT)
235		return IRQ_NONE;
 
236	lsr = serial_in(up, UART_LSR);
237	if (lsr & UART_LSR_DR)
238		receive_chars(up, &lsr);
239	check_modem_status(up);
240	if (lsr & UART_LSR_THRE)
241		transmit_chars(up);
 
242	return IRQ_HANDLED;
243}
244
245static unsigned int serial_pxa_tx_empty(struct uart_port *port)
246{
247	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
248	unsigned long flags;
249	unsigned int ret;
250
251	spin_lock_irqsave(&up->port.lock, flags);
252	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
253	spin_unlock_irqrestore(&up->port.lock, flags);
254
255	return ret;
256}
257
258static unsigned int serial_pxa_get_mctrl(struct uart_port *port)
259{
260	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
261	unsigned char status;
262	unsigned int ret;
263
264	status = serial_in(up, UART_MSR);
265
266	ret = 0;
267	if (status & UART_MSR_DCD)
268		ret |= TIOCM_CAR;
269	if (status & UART_MSR_RI)
270		ret |= TIOCM_RNG;
271	if (status & UART_MSR_DSR)
272		ret |= TIOCM_DSR;
273	if (status & UART_MSR_CTS)
274		ret |= TIOCM_CTS;
275	return ret;
276}
277
278static void serial_pxa_set_mctrl(struct uart_port *port, unsigned int mctrl)
279{
280	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
281	unsigned char mcr = 0;
282
283	if (mctrl & TIOCM_RTS)
284		mcr |= UART_MCR_RTS;
285	if (mctrl & TIOCM_DTR)
286		mcr |= UART_MCR_DTR;
287	if (mctrl & TIOCM_OUT1)
288		mcr |= UART_MCR_OUT1;
289	if (mctrl & TIOCM_OUT2)
290		mcr |= UART_MCR_OUT2;
291	if (mctrl & TIOCM_LOOP)
292		mcr |= UART_MCR_LOOP;
293
294	mcr |= up->mcr;
295
296	serial_out(up, UART_MCR, mcr);
297}
298
299static void serial_pxa_break_ctl(struct uart_port *port, int break_state)
300{
301	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
302	unsigned long flags;
303
304	spin_lock_irqsave(&up->port.lock, flags);
305	if (break_state == -1)
306		up->lcr |= UART_LCR_SBC;
307	else
308		up->lcr &= ~UART_LCR_SBC;
309	serial_out(up, UART_LCR, up->lcr);
310	spin_unlock_irqrestore(&up->port.lock, flags);
311}
312
313#if 0
314static void serial_pxa_dma_init(struct pxa_uart *up)
315{
316	up->rxdma =
317		pxa_request_dma(up->name, DMA_PRIO_LOW, pxa_receive_dma, up);
318	if (up->rxdma < 0)
319		goto out;
320	up->txdma =
321		pxa_request_dma(up->name, DMA_PRIO_LOW, pxa_transmit_dma, up);
322	if (up->txdma < 0)
323		goto err_txdma;
324	up->dmadesc = kmalloc(4 * sizeof(pxa_dma_desc), GFP_KERNEL);
325	if (!up->dmadesc)
326		goto err_alloc;
327
328	/* ... */
329err_alloc:
330	pxa_free_dma(up->txdma);
331err_rxdma:
332	pxa_free_dma(up->rxdma);
333out:
334	return;
335}
336#endif
337
338static int serial_pxa_startup(struct uart_port *port)
339{
340	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
341	unsigned long flags;
342	int retval;
343
344	if (port->line == 3) /* HWUART */
345		up->mcr |= UART_MCR_AFE;
346	else
347		up->mcr = 0;
348
349	up->port.uartclk = clk_get_rate(up->clk);
350
351	/*
352	 * Allocate the IRQ
353	 */
354	retval = request_irq(up->port.irq, serial_pxa_irq, 0, up->name, up);
355	if (retval)
356		return retval;
357
358	/*
359	 * Clear the FIFO buffers and disable them.
360	 * (they will be reenabled in set_termios())
361	 */
362	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
363	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
364			UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
365	serial_out(up, UART_FCR, 0);
366
367	/*
368	 * Clear the interrupt registers.
369	 */
370	(void) serial_in(up, UART_LSR);
371	(void) serial_in(up, UART_RX);
372	(void) serial_in(up, UART_IIR);
373	(void) serial_in(up, UART_MSR);
374
375	/*
376	 * Now, initialize the UART
377	 */
378	serial_out(up, UART_LCR, UART_LCR_WLEN8);
379
380	spin_lock_irqsave(&up->port.lock, flags);
381	up->port.mctrl |= TIOCM_OUT2;
382	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
383	spin_unlock_irqrestore(&up->port.lock, flags);
384
385	/*
386	 * Finally, enable interrupts.  Note: Modem status interrupts
387	 * are set via set_termios(), which will be occurring imminently
388	 * anyway, so we don't enable them here.
389	 */
390	up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE | UART_IER_UUE;
391	serial_out(up, UART_IER, up->ier);
392
393	/*
394	 * And clear the interrupt registers again for luck.
395	 */
396	(void) serial_in(up, UART_LSR);
397	(void) serial_in(up, UART_RX);
398	(void) serial_in(up, UART_IIR);
399	(void) serial_in(up, UART_MSR);
400
401	return 0;
402}
403
404static void serial_pxa_shutdown(struct uart_port *port)
405{
406	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
407	unsigned long flags;
408
409	free_irq(up->port.irq, up);
410
411	/*
412	 * Disable interrupts from this port
413	 */
414	up->ier = 0;
415	serial_out(up, UART_IER, 0);
416
417	spin_lock_irqsave(&up->port.lock, flags);
418	up->port.mctrl &= ~TIOCM_OUT2;
419	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
420	spin_unlock_irqrestore(&up->port.lock, flags);
421
422	/*
423	 * Disable break condition and FIFOs
424	 */
425	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
426	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
427				  UART_FCR_CLEAR_RCVR |
428				  UART_FCR_CLEAR_XMIT);
429	serial_out(up, UART_FCR, 0);
430}
431
432static void
433serial_pxa_set_termios(struct uart_port *port, struct ktermios *termios,
434		       struct ktermios *old)
435{
436	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
437	unsigned char cval, fcr = 0;
438	unsigned long flags;
439	unsigned int baud, quot;
440	unsigned int dll;
441
442	switch (termios->c_cflag & CSIZE) {
443	case CS5:
444		cval = UART_LCR_WLEN5;
445		break;
446	case CS6:
447		cval = UART_LCR_WLEN6;
448		break;
449	case CS7:
450		cval = UART_LCR_WLEN7;
451		break;
452	default:
453	case CS8:
454		cval = UART_LCR_WLEN8;
455		break;
456	}
457
458	if (termios->c_cflag & CSTOPB)
459		cval |= UART_LCR_STOP;
460	if (termios->c_cflag & PARENB)
461		cval |= UART_LCR_PARITY;
462	if (!(termios->c_cflag & PARODD))
463		cval |= UART_LCR_EPAR;
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	if ((up->port.uartclk / quot) < (2400 * 16))
472		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR1;
473	else if ((up->port.uartclk / quot) < (230400 * 16))
474		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR8;
475	else
476		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR32;
477
478	/*
479	 * Ok, we're now changing the port state.  Do it with
480	 * interrupts disabled.
481	 */
482	spin_lock_irqsave(&up->port.lock, flags);
483
484	/*
485	 * Ensure the port will be enabled.
486	 * This is required especially for serial console.
487	 */
488	up->ier |= UART_IER_UUE;
489
490	/*
491	 * Update the per-port timeout.
492	 */
493	uart_update_timeout(port, termios->c_cflag, baud);
494
495	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
496	if (termios->c_iflag & INPCK)
497		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
498	if (termios->c_iflag & (BRKINT | PARMRK))
499		up->port.read_status_mask |= UART_LSR_BI;
500
501	/*
502	 * Characters to ignore
503	 */
504	up->port.ignore_status_mask = 0;
505	if (termios->c_iflag & IGNPAR)
506		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
507	if (termios->c_iflag & IGNBRK) {
508		up->port.ignore_status_mask |= UART_LSR_BI;
509		/*
510		 * If we're ignoring parity and break indicators,
511		 * ignore overruns too (for real raw support).
512		 */
513		if (termios->c_iflag & IGNPAR)
514			up->port.ignore_status_mask |= UART_LSR_OE;
515	}
516
517	/*
518	 * ignore all characters if CREAD is not set
519	 */
520	if ((termios->c_cflag & CREAD) == 0)
521		up->port.ignore_status_mask |= UART_LSR_DR;
522
523	/*
524	 * CTS flow control flag and modem status interrupts
525	 */
526	up->ier &= ~UART_IER_MSI;
527	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
528		up->ier |= UART_IER_MSI;
529
530	serial_out(up, UART_IER, up->ier);
531
532	if (termios->c_cflag & CRTSCTS)
533		up->mcr |= UART_MCR_AFE;
534	else
535		up->mcr &= ~UART_MCR_AFE;
536
537	serial_out(up, UART_LCR, cval | UART_LCR_DLAB);	/* set DLAB */
538	serial_out(up, UART_DLL, quot & 0xff);		/* LS of divisor */
539
540	/*
541	 * work around Errata #75 according to Intel(R) PXA27x Processor Family
542	 * Specification Update (Nov 2005)
543	 */
544	dll = serial_in(up, UART_DLL);
545	WARN_ON(dll != (quot & 0xff));
546
547	serial_out(up, UART_DLM, quot >> 8);		/* MS of divisor */
548	serial_out(up, UART_LCR, cval);			/* reset DLAB */
549	up->lcr = cval;					/* Save LCR */
550	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
551	serial_out(up, UART_FCR, fcr);
552	spin_unlock_irqrestore(&up->port.lock, flags);
553}
554
555static void
556serial_pxa_pm(struct uart_port *port, unsigned int state,
557	      unsigned int oldstate)
558{
559	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
560
561	if (!state)
562		clk_enable(up->clk);
563	else
564		clk_disable(up->clk);
565}
566
567static void serial_pxa_release_port(struct uart_port *port)
568{
569}
570
571static int serial_pxa_request_port(struct uart_port *port)
572{
573	return 0;
574}
575
576static void serial_pxa_config_port(struct uart_port *port, int flags)
577{
578	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
579	up->port.type = PORT_PXA;
580}
581
582static int
583serial_pxa_verify_port(struct uart_port *port, struct serial_struct *ser)
584{
585	/* we don't want the core code to modify any port params */
586	return -EINVAL;
587}
588
589static const char *
590serial_pxa_type(struct uart_port *port)
591{
592	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
593	return up->name;
594}
595
596static struct uart_pxa_port *serial_pxa_ports[4];
597static struct uart_driver serial_pxa_reg;
598
599#ifdef CONFIG_SERIAL_PXA_CONSOLE
600
601#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
602
603/*
604 *	Wait for transmitter & holding register to empty
605 */
606static inline void wait_for_xmitr(struct uart_pxa_port *up)
607{
608	unsigned int status, tmout = 10000;
609
610	/* Wait up to 10ms for the character(s) to be sent. */
611	do {
612		status = serial_in(up, UART_LSR);
613
614		if (status & UART_LSR_BI)
615			up->lsr_break_flag = UART_LSR_BI;
616
617		if (--tmout == 0)
618			break;
619		udelay(1);
620	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
621
622	/* Wait up to 1s for flow control if necessary */
623	if (up->port.flags & UPF_CONS_FLOW) {
624		tmout = 1000000;
625		while (--tmout &&
626		       ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
627			udelay(1);
628	}
629}
630
631static void serial_pxa_console_putchar(struct uart_port *port, int ch)
632{
633	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
634
635	wait_for_xmitr(up);
636	serial_out(up, UART_TX, ch);
637}
638
639/*
640 * Print a string to the serial port trying not to disturb
641 * any possible real use of the port...
642 *
643 *	The console_lock must be held when we get here.
644 */
645static void
646serial_pxa_console_write(struct console *co, const char *s, unsigned int count)
647{
648	struct uart_pxa_port *up = serial_pxa_ports[co->index];
649	unsigned int ier;
 
 
650
651	clk_enable(up->clk);
 
 
 
 
 
 
 
652
653	/*
654	 *	First save the IER then disable the interrupts
655	 */
656	ier = serial_in(up, UART_IER);
657	serial_out(up, UART_IER, UART_IER_UUE);
658
659	uart_console_write(&up->port, s, count, serial_pxa_console_putchar);
660
661	/*
662	 *	Finally, wait for transmitter to become empty
663	 *	and restore the IER
664	 */
665	wait_for_xmitr(up);
666	serial_out(up, UART_IER, ier);
667
 
 
 
668	clk_disable(up->clk);
 
669}
670
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
671static int __init
672serial_pxa_console_setup(struct console *co, char *options)
673{
674	struct uart_pxa_port *up;
675	int baud = 9600;
676	int bits = 8;
677	int parity = 'n';
678	int flow = 'n';
679
680	if (co->index == -1 || co->index >= serial_pxa_reg.nr)
681		co->index = 0;
682	up = serial_pxa_ports[co->index];
683	if (!up)
684		return -ENODEV;
685
686	if (options)
687		uart_parse_options(options, &baud, &parity, &bits, &flow);
688
689	return uart_set_options(&up->port, co, baud, parity, bits, flow);
690}
691
692static struct console serial_pxa_console = {
693	.name		= "ttyS",
694	.write		= serial_pxa_console_write,
695	.device		= uart_console_device,
696	.setup		= serial_pxa_console_setup,
697	.flags		= CON_PRINTBUFFER,
698	.index		= -1,
699	.data		= &serial_pxa_reg,
700};
701
702#define PXA_CONSOLE	&serial_pxa_console
703#else
704#define PXA_CONSOLE	NULL
705#endif
706
707struct uart_ops serial_pxa_pops = {
708	.tx_empty	= serial_pxa_tx_empty,
709	.set_mctrl	= serial_pxa_set_mctrl,
710	.get_mctrl	= serial_pxa_get_mctrl,
711	.stop_tx	= serial_pxa_stop_tx,
712	.start_tx	= serial_pxa_start_tx,
713	.stop_rx	= serial_pxa_stop_rx,
714	.enable_ms	= serial_pxa_enable_ms,
715	.break_ctl	= serial_pxa_break_ctl,
716	.startup	= serial_pxa_startup,
717	.shutdown	= serial_pxa_shutdown,
718	.set_termios	= serial_pxa_set_termios,
719	.pm		= serial_pxa_pm,
720	.type		= serial_pxa_type,
721	.release_port	= serial_pxa_release_port,
722	.request_port	= serial_pxa_request_port,
723	.config_port	= serial_pxa_config_port,
724	.verify_port	= serial_pxa_verify_port,
 
 
 
 
725};
726
727static struct uart_driver serial_pxa_reg = {
728	.owner		= THIS_MODULE,
729	.driver_name	= "PXA serial",
730	.dev_name	= "ttyS",
731	.major		= TTY_MAJOR,
732	.minor		= 64,
733	.nr		= 4,
734	.cons		= PXA_CONSOLE,
735};
736
737#ifdef CONFIG_PM
738static int serial_pxa_suspend(struct device *dev)
739{
740        struct uart_pxa_port *sport = dev_get_drvdata(dev);
741
742        if (sport)
743                uart_suspend_port(&serial_pxa_reg, &sport->port);
744
745        return 0;
746}
747
748static int serial_pxa_resume(struct device *dev)
749{
750        struct uart_pxa_port *sport = dev_get_drvdata(dev);
751
752        if (sport)
753                uart_resume_port(&serial_pxa_reg, &sport->port);
754
755        return 0;
756}
757
758static const struct dev_pm_ops serial_pxa_pm_ops = {
759	.suspend	= serial_pxa_suspend,
760	.resume		= serial_pxa_resume,
761};
762#endif
763
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
764static int serial_pxa_probe(struct platform_device *dev)
765{
766	struct uart_pxa_port *sport;
767	struct resource *mmres, *irqres;
768	int ret;
769
770	mmres = platform_get_resource(dev, IORESOURCE_MEM, 0);
771	irqres = platform_get_resource(dev, IORESOURCE_IRQ, 0);
772	if (!mmres || !irqres)
773		return -ENODEV;
774
775	sport = kzalloc(sizeof(struct uart_pxa_port), GFP_KERNEL);
776	if (!sport)
777		return -ENOMEM;
778
779	sport->clk = clk_get(&dev->dev, NULL);
780	if (IS_ERR(sport->clk)) {
781		ret = PTR_ERR(sport->clk);
782		goto err_free;
783	}
784
 
 
 
 
 
 
785	sport->port.type = PORT_PXA;
786	sport->port.iotype = UPIO_MEM;
787	sport->port.mapbase = mmres->start;
788	sport->port.irq = irqres->start;
789	sport->port.fifosize = 64;
790	sport->port.ops = &serial_pxa_pops;
791	sport->port.line = dev->id;
792	sport->port.dev = &dev->dev;
793	sport->port.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF;
794	sport->port.uartclk = clk_get_rate(sport->clk);
795
796	switch (dev->id) {
797	case 0: sport->name = "FFUART"; break;
798	case 1: sport->name = "BTUART"; break;
799	case 2: sport->name = "STUART"; break;
800	case 3: sport->name = "HWUART"; break;
801	default:
802		sport->name = "???";
803		break;
804	}
805
806	sport->port.membase = ioremap(mmres->start, resource_size(mmres));
807	if (!sport->port.membase) {
808		ret = -ENOMEM;
809		goto err_clk;
810	}
811
812	serial_pxa_ports[dev->id] = sport;
813
814	uart_add_one_port(&serial_pxa_reg, &sport->port);
815	platform_set_drvdata(dev, sport);
816
817	return 0;
818
819 err_clk:
 
820	clk_put(sport->clk);
821 err_free:
822	kfree(sport);
823	return ret;
824}
825
826static int serial_pxa_remove(struct platform_device *dev)
827{
828	struct uart_pxa_port *sport = platform_get_drvdata(dev);
829
830	platform_set_drvdata(dev, NULL);
831
832	uart_remove_one_port(&serial_pxa_reg, &sport->port);
833	clk_put(sport->clk);
834	kfree(sport);
835
836	return 0;
837}
838
839static struct platform_driver serial_pxa_driver = {
840        .probe          = serial_pxa_probe,
841        .remove         = serial_pxa_remove,
842
843	.driver		= {
844	        .name	= "pxa2xx-uart",
845		.owner	= THIS_MODULE,
846#ifdef CONFIG_PM
847		.pm	= &serial_pxa_pm_ops,
848#endif
 
 
849	},
850};
851
852int __init serial_pxa_init(void)
 
 
853{
854	int ret;
855
856	ret = uart_register_driver(&serial_pxa_reg);
857	if (ret != 0)
858		return ret;
859
860	ret = platform_driver_register(&serial_pxa_driver);
861	if (ret != 0)
862		uart_unregister_driver(&serial_pxa_reg);
863
864	return ret;
865}
866
867void __exit serial_pxa_exit(void)
868{
869	platform_driver_unregister(&serial_pxa_driver);
870	uart_unregister_driver(&serial_pxa_reg);
871}
872
873module_init(serial_pxa_init);
874module_exit(serial_pxa_exit);
875
876MODULE_LICENSE("GPL");
877MODULE_ALIAS("platform:pxa2xx-uart");
v4.10.11
  1/*
  2 *  Based on drivers/serial/8250.c by Russell King.
  3 *
  4 *  Author:	Nicolas Pitre
  5 *  Created:	Feb 20, 2003
  6 *  Copyright:	(C) 2003 Monta Vista Software, Inc.
  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 * Note 1: This driver is made separate from the already too overloaded
 14 * 8250.c because it needs some kirks of its own and that'll make it
 15 * easier to add DMA support.
 16 *
 17 * Note 2: I'm too sick of device allocation policies for serial ports.
 18 * If someone else wants to request an "official" allocation of major/minor
 19 * for this driver please be my guest.  And don't forget that new hardware
 20 * to come from Intel might have more than 3 or 4 of those UARTs.  Let's
 21 * hope for a better port registration and dynamic device allocation scheme
 22 * with the serial core maintainer satisfaction to appear soon.
 23 */
 24
 25
 26#if defined(CONFIG_SERIAL_PXA_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
 27#define SUPPORT_SYSRQ
 28#endif
 29
 
 30#include <linux/ioport.h>
 31#include <linux/init.h>
 32#include <linux/console.h>
 33#include <linux/sysrq.h>
 34#include <linux/serial_reg.h>
 35#include <linux/circ_buf.h>
 36#include <linux/delay.h>
 37#include <linux/interrupt.h>
 38#include <linux/of.h>
 39#include <linux/platform_device.h>
 40#include <linux/tty.h>
 41#include <linux/tty_flip.h>
 42#include <linux/serial_core.h>
 43#include <linux/clk.h>
 44#include <linux/io.h>
 45#include <linux/slab.h>
 46
 47#define PXA_NAME_LEN		8
 48
 49struct uart_pxa_port {
 50	struct uart_port        port;
 51	unsigned char           ier;
 52	unsigned char           lcr;
 53	unsigned char           mcr;
 54	unsigned int            lsr_break_flag;
 55	struct clk		*clk;
 56	char			name[PXA_NAME_LEN];
 57};
 58
 59static inline unsigned int serial_in(struct uart_pxa_port *up, int offset)
 60{
 61	offset <<= 2;
 62	return readl(up->port.membase + offset);
 63}
 64
 65static inline void serial_out(struct uart_pxa_port *up, int offset, int value)
 66{
 67	offset <<= 2;
 68	writel(value, up->port.membase + offset);
 69}
 70
 71static void serial_pxa_enable_ms(struct uart_port *port)
 72{
 73	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
 74
 75	up->ier |= UART_IER_MSI;
 76	serial_out(up, UART_IER, up->ier);
 77}
 78
 79static void serial_pxa_stop_tx(struct uart_port *port)
 80{
 81	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
 82
 83	if (up->ier & UART_IER_THRI) {
 84		up->ier &= ~UART_IER_THRI;
 85		serial_out(up, UART_IER, up->ier);
 86	}
 87}
 88
 89static void serial_pxa_stop_rx(struct uart_port *port)
 90{
 91	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
 92
 93	up->ier &= ~UART_IER_RLSI;
 94	up->port.read_status_mask &= ~UART_LSR_DR;
 95	serial_out(up, UART_IER, up->ier);
 96}
 97
 98static inline void receive_chars(struct uart_pxa_port *up, int *status)
 99{
 
100	unsigned int ch, flag;
101	int max_count = 256;
102
103	do {
104		/* work around Errata #20 according to
105		 * Intel(R) PXA27x Processor Family
106		 * Specification Update (May 2005)
107		 *
108		 * Step 2
109		 * Disable the Reciever Time Out Interrupt via IER[RTOEI]
110		 */
111		up->ier &= ~UART_IER_RTOIE;
112		serial_out(up, UART_IER, up->ier);
113
114		ch = serial_in(up, UART_RX);
115		flag = TTY_NORMAL;
116		up->port.icount.rx++;
117
118		if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
119				       UART_LSR_FE | UART_LSR_OE))) {
120			/*
121			 * For statistics only
122			 */
123			if (*status & UART_LSR_BI) {
124				*status &= ~(UART_LSR_FE | UART_LSR_PE);
125				up->port.icount.brk++;
126				/*
127				 * We do the SysRQ and SAK checking
128				 * here because otherwise the break
129				 * may get masked by ignore_status_mask
130				 * or read_status_mask.
131				 */
132				if (uart_handle_break(&up->port))
133					goto ignore_char;
134			} else if (*status & UART_LSR_PE)
135				up->port.icount.parity++;
136			else if (*status & UART_LSR_FE)
137				up->port.icount.frame++;
138			if (*status & UART_LSR_OE)
139				up->port.icount.overrun++;
140
141			/*
142			 * Mask off conditions which should be ignored.
143			 */
144			*status &= up->port.read_status_mask;
145
146#ifdef CONFIG_SERIAL_PXA_CONSOLE
147			if (up->port.line == up->port.cons->index) {
148				/* Recover the break flag from console xmit */
149				*status |= up->lsr_break_flag;
150				up->lsr_break_flag = 0;
151			}
152#endif
153			if (*status & UART_LSR_BI) {
154				flag = TTY_BREAK;
155			} else if (*status & UART_LSR_PE)
156				flag = TTY_PARITY;
157			else if (*status & UART_LSR_FE)
158				flag = TTY_FRAME;
159		}
160
161		if (uart_handle_sysrq_char(&up->port, ch))
162			goto ignore_char;
163
164		uart_insert_char(&up->port, *status, UART_LSR_OE, ch, flag);
165
166	ignore_char:
167		*status = serial_in(up, UART_LSR);
168	} while ((*status & UART_LSR_DR) && (max_count-- > 0));
169	tty_flip_buffer_push(&up->port.state->port);
170
171	/* work around Errata #20 according to
172	 * Intel(R) PXA27x Processor Family
173	 * Specification Update (May 2005)
174	 *
175	 * Step 6:
176	 * No more data in FIFO: Re-enable RTO interrupt via IER[RTOIE]
177	 */
178	up->ier |= UART_IER_RTOIE;
179	serial_out(up, UART_IER, up->ier);
180}
181
182static void transmit_chars(struct uart_pxa_port *up)
183{
184	struct circ_buf *xmit = &up->port.state->xmit;
185	int count;
186
187	if (up->port.x_char) {
188		serial_out(up, UART_TX, up->port.x_char);
189		up->port.icount.tx++;
190		up->port.x_char = 0;
191		return;
192	}
193	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
194		serial_pxa_stop_tx(&up->port);
195		return;
196	}
197
198	count = up->port.fifosize / 2;
199	do {
200		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
201		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
202		up->port.icount.tx++;
203		if (uart_circ_empty(xmit))
204			break;
205	} while (--count > 0);
206
207	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
208		uart_write_wakeup(&up->port);
209
210
211	if (uart_circ_empty(xmit))
212		serial_pxa_stop_tx(&up->port);
213}
214
215static void serial_pxa_start_tx(struct uart_port *port)
216{
217	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
218
219	if (!(up->ier & UART_IER_THRI)) {
220		up->ier |= UART_IER_THRI;
221		serial_out(up, UART_IER, up->ier);
222	}
223}
224
225/* should hold up->port.lock */
226static inline void check_modem_status(struct uart_pxa_port *up)
227{
228	int status;
229
230	status = serial_in(up, UART_MSR);
231
232	if ((status & UART_MSR_ANY_DELTA) == 0)
233		return;
234
235	if (status & UART_MSR_TERI)
236		up->port.icount.rng++;
237	if (status & UART_MSR_DDSR)
238		up->port.icount.dsr++;
239	if (status & UART_MSR_DDCD)
240		uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
241	if (status & UART_MSR_DCTS)
242		uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
243
244	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
245}
246
247/*
248 * This handles the interrupt from one port.
249 */
250static inline irqreturn_t serial_pxa_irq(int irq, void *dev_id)
251{
252	struct uart_pxa_port *up = dev_id;
253	unsigned int iir, lsr;
254
255	iir = serial_in(up, UART_IIR);
256	if (iir & UART_IIR_NO_INT)
257		return IRQ_NONE;
258	spin_lock(&up->port.lock);
259	lsr = serial_in(up, UART_LSR);
260	if (lsr & UART_LSR_DR)
261		receive_chars(up, &lsr);
262	check_modem_status(up);
263	if (lsr & UART_LSR_THRE)
264		transmit_chars(up);
265	spin_unlock(&up->port.lock);
266	return IRQ_HANDLED;
267}
268
269static unsigned int serial_pxa_tx_empty(struct uart_port *port)
270{
271	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
272	unsigned long flags;
273	unsigned int ret;
274
275	spin_lock_irqsave(&up->port.lock, flags);
276	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
277	spin_unlock_irqrestore(&up->port.lock, flags);
278
279	return ret;
280}
281
282static unsigned int serial_pxa_get_mctrl(struct uart_port *port)
283{
284	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
285	unsigned char status;
286	unsigned int ret;
287
288	status = serial_in(up, UART_MSR);
289
290	ret = 0;
291	if (status & UART_MSR_DCD)
292		ret |= TIOCM_CAR;
293	if (status & UART_MSR_RI)
294		ret |= TIOCM_RNG;
295	if (status & UART_MSR_DSR)
296		ret |= TIOCM_DSR;
297	if (status & UART_MSR_CTS)
298		ret |= TIOCM_CTS;
299	return ret;
300}
301
302static void serial_pxa_set_mctrl(struct uart_port *port, unsigned int mctrl)
303{
304	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
305	unsigned char mcr = 0;
306
307	if (mctrl & TIOCM_RTS)
308		mcr |= UART_MCR_RTS;
309	if (mctrl & TIOCM_DTR)
310		mcr |= UART_MCR_DTR;
311	if (mctrl & TIOCM_OUT1)
312		mcr |= UART_MCR_OUT1;
313	if (mctrl & TIOCM_OUT2)
314		mcr |= UART_MCR_OUT2;
315	if (mctrl & TIOCM_LOOP)
316		mcr |= UART_MCR_LOOP;
317
318	mcr |= up->mcr;
319
320	serial_out(up, UART_MCR, mcr);
321}
322
323static void serial_pxa_break_ctl(struct uart_port *port, int break_state)
324{
325	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
326	unsigned long flags;
327
328	spin_lock_irqsave(&up->port.lock, flags);
329	if (break_state == -1)
330		up->lcr |= UART_LCR_SBC;
331	else
332		up->lcr &= ~UART_LCR_SBC;
333	serial_out(up, UART_LCR, up->lcr);
334	spin_unlock_irqrestore(&up->port.lock, flags);
335}
336
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
337static int serial_pxa_startup(struct uart_port *port)
338{
339	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
340	unsigned long flags;
341	int retval;
342
343	if (port->line == 3) /* HWUART */
344		up->mcr |= UART_MCR_AFE;
345	else
346		up->mcr = 0;
347
348	up->port.uartclk = clk_get_rate(up->clk);
349
350	/*
351	 * Allocate the IRQ
352	 */
353	retval = request_irq(up->port.irq, serial_pxa_irq, 0, up->name, up);
354	if (retval)
355		return retval;
356
357	/*
358	 * Clear the FIFO buffers and disable them.
359	 * (they will be reenabled in set_termios())
360	 */
361	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
362	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
363			UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
364	serial_out(up, UART_FCR, 0);
365
366	/*
367	 * Clear the interrupt registers.
368	 */
369	(void) serial_in(up, UART_LSR);
370	(void) serial_in(up, UART_RX);
371	(void) serial_in(up, UART_IIR);
372	(void) serial_in(up, UART_MSR);
373
374	/*
375	 * Now, initialize the UART
376	 */
377	serial_out(up, UART_LCR, UART_LCR_WLEN8);
378
379	spin_lock_irqsave(&up->port.lock, flags);
380	up->port.mctrl |= TIOCM_OUT2;
381	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
382	spin_unlock_irqrestore(&up->port.lock, flags);
383
384	/*
385	 * Finally, enable interrupts.  Note: Modem status interrupts
386	 * are set via set_termios(), which will be occurring imminently
387	 * anyway, so we don't enable them here.
388	 */
389	up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE | UART_IER_UUE;
390	serial_out(up, UART_IER, up->ier);
391
392	/*
393	 * And clear the interrupt registers again for luck.
394	 */
395	(void) serial_in(up, UART_LSR);
396	(void) serial_in(up, UART_RX);
397	(void) serial_in(up, UART_IIR);
398	(void) serial_in(up, UART_MSR);
399
400	return 0;
401}
402
403static void serial_pxa_shutdown(struct uart_port *port)
404{
405	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
406	unsigned long flags;
407
408	free_irq(up->port.irq, up);
409
410	/*
411	 * Disable interrupts from this port
412	 */
413	up->ier = 0;
414	serial_out(up, UART_IER, 0);
415
416	spin_lock_irqsave(&up->port.lock, flags);
417	up->port.mctrl &= ~TIOCM_OUT2;
418	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
419	spin_unlock_irqrestore(&up->port.lock, flags);
420
421	/*
422	 * Disable break condition and FIFOs
423	 */
424	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
425	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
426				  UART_FCR_CLEAR_RCVR |
427				  UART_FCR_CLEAR_XMIT);
428	serial_out(up, UART_FCR, 0);
429}
430
431static void
432serial_pxa_set_termios(struct uart_port *port, struct ktermios *termios,
433		       struct ktermios *old)
434{
435	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
436	unsigned char cval, fcr = 0;
437	unsigned long flags;
438	unsigned int baud, quot;
439	unsigned int dll;
440
441	switch (termios->c_cflag & CSIZE) {
442	case CS5:
443		cval = UART_LCR_WLEN5;
444		break;
445	case CS6:
446		cval = UART_LCR_WLEN6;
447		break;
448	case CS7:
449		cval = UART_LCR_WLEN7;
450		break;
451	default:
452	case CS8:
453		cval = UART_LCR_WLEN8;
454		break;
455	}
456
457	if (termios->c_cflag & CSTOPB)
458		cval |= UART_LCR_STOP;
459	if (termios->c_cflag & PARENB)
460		cval |= UART_LCR_PARITY;
461	if (!(termios->c_cflag & PARODD))
462		cval |= UART_LCR_EPAR;
463
464	/*
465	 * Ask the core to calculate the divisor for us.
466	 */
467	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
468	quot = uart_get_divisor(port, baud);
469
470	if ((up->port.uartclk / quot) < (2400 * 16))
471		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR1;
472	else if ((up->port.uartclk / quot) < (230400 * 16))
473		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR8;
474	else
475		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR32;
476
477	/*
478	 * Ok, we're now changing the port state.  Do it with
479	 * interrupts disabled.
480	 */
481	spin_lock_irqsave(&up->port.lock, flags);
482
483	/*
484	 * Ensure the port will be enabled.
485	 * This is required especially for serial console.
486	 */
487	up->ier |= UART_IER_UUE;
488
489	/*
490	 * Update the per-port timeout.
491	 */
492	uart_update_timeout(port, termios->c_cflag, baud);
493
494	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
495	if (termios->c_iflag & INPCK)
496		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
497	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
498		up->port.read_status_mask |= UART_LSR_BI;
499
500	/*
501	 * Characters to ignore
502	 */
503	up->port.ignore_status_mask = 0;
504	if (termios->c_iflag & IGNPAR)
505		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
506	if (termios->c_iflag & IGNBRK) {
507		up->port.ignore_status_mask |= UART_LSR_BI;
508		/*
509		 * If we're ignoring parity and break indicators,
510		 * ignore overruns too (for real raw support).
511		 */
512		if (termios->c_iflag & IGNPAR)
513			up->port.ignore_status_mask |= UART_LSR_OE;
514	}
515
516	/*
517	 * ignore all characters if CREAD is not set
518	 */
519	if ((termios->c_cflag & CREAD) == 0)
520		up->port.ignore_status_mask |= UART_LSR_DR;
521
522	/*
523	 * CTS flow control flag and modem status interrupts
524	 */
525	up->ier &= ~UART_IER_MSI;
526	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
527		up->ier |= UART_IER_MSI;
528
529	serial_out(up, UART_IER, up->ier);
530
531	if (termios->c_cflag & CRTSCTS)
532		up->mcr |= UART_MCR_AFE;
533	else
534		up->mcr &= ~UART_MCR_AFE;
535
536	serial_out(up, UART_LCR, cval | UART_LCR_DLAB);	/* set DLAB */
537	serial_out(up, UART_DLL, quot & 0xff);		/* LS of divisor */
538
539	/*
540	 * work around Errata #75 according to Intel(R) PXA27x Processor Family
541	 * Specification Update (Nov 2005)
542	 */
543	dll = serial_in(up, UART_DLL);
544	WARN_ON(dll != (quot & 0xff));
545
546	serial_out(up, UART_DLM, quot >> 8);		/* MS of divisor */
547	serial_out(up, UART_LCR, cval);			/* reset DLAB */
548	up->lcr = cval;					/* Save LCR */
549	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
550	serial_out(up, UART_FCR, fcr);
551	spin_unlock_irqrestore(&up->port.lock, flags);
552}
553
554static void
555serial_pxa_pm(struct uart_port *port, unsigned int state,
556	      unsigned int oldstate)
557{
558	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
559
560	if (!state)
561		clk_prepare_enable(up->clk);
562	else
563		clk_disable_unprepare(up->clk);
564}
565
566static void serial_pxa_release_port(struct uart_port *port)
567{
568}
569
570static int serial_pxa_request_port(struct uart_port *port)
571{
572	return 0;
573}
574
575static void serial_pxa_config_port(struct uart_port *port, int flags)
576{
577	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
578	up->port.type = PORT_PXA;
579}
580
581static int
582serial_pxa_verify_port(struct uart_port *port, struct serial_struct *ser)
583{
584	/* we don't want the core code to modify any port params */
585	return -EINVAL;
586}
587
588static const char *
589serial_pxa_type(struct uart_port *port)
590{
591	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
592	return up->name;
593}
594
595static struct uart_pxa_port *serial_pxa_ports[4];
596static struct uart_driver serial_pxa_reg;
597
598#ifdef CONFIG_SERIAL_PXA_CONSOLE
599
600#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
601
602/*
603 *	Wait for transmitter & holding register to empty
604 */
605static void wait_for_xmitr(struct uart_pxa_port *up)
606{
607	unsigned int status, tmout = 10000;
608
609	/* Wait up to 10ms for the character(s) to be sent. */
610	do {
611		status = serial_in(up, UART_LSR);
612
613		if (status & UART_LSR_BI)
614			up->lsr_break_flag = UART_LSR_BI;
615
616		if (--tmout == 0)
617			break;
618		udelay(1);
619	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
620
621	/* Wait up to 1s for flow control if necessary */
622	if (up->port.flags & UPF_CONS_FLOW) {
623		tmout = 1000000;
624		while (--tmout &&
625		       ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
626			udelay(1);
627	}
628}
629
630static void serial_pxa_console_putchar(struct uart_port *port, int ch)
631{
632	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
633
634	wait_for_xmitr(up);
635	serial_out(up, UART_TX, ch);
636}
637
638/*
639 * Print a string to the serial port trying not to disturb
640 * any possible real use of the port...
641 *
642 *	The console_lock must be held when we get here.
643 */
644static void
645serial_pxa_console_write(struct console *co, const char *s, unsigned int count)
646{
647	struct uart_pxa_port *up = serial_pxa_ports[co->index];
648	unsigned int ier;
649	unsigned long flags;
650	int locked = 1;
651
652	clk_enable(up->clk);
653	local_irq_save(flags);
654	if (up->port.sysrq)
655		locked = 0;
656	else if (oops_in_progress)
657		locked = spin_trylock(&up->port.lock);
658	else
659		spin_lock(&up->port.lock);
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	uart_console_write(&up->port, s, count, serial_pxa_console_putchar);
668
669	/*
670	 *	Finally, wait for transmitter to become empty
671	 *	and restore the IER
672	 */
673	wait_for_xmitr(up);
674	serial_out(up, UART_IER, ier);
675
676	if (locked)
677		spin_unlock(&up->port.lock);
678	local_irq_restore(flags);
679	clk_disable(up->clk);
680
681}
682
683#ifdef CONFIG_CONSOLE_POLL
684/*
685 * Console polling routines for writing and reading from the uart while
686 * in an interrupt or debug context.
687 */
688
689static int serial_pxa_get_poll_char(struct uart_port *port)
690{
691	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
692	unsigned char lsr = serial_in(up, UART_LSR);
693
694	while (!(lsr & UART_LSR_DR))
695		lsr = serial_in(up, UART_LSR);
696
697	return serial_in(up, UART_RX);
698}
699
700
701static void serial_pxa_put_poll_char(struct uart_port *port,
702			 unsigned char c)
703{
704	unsigned int ier;
705	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
706
707	/*
708	 *	First save the IER then disable the interrupts
709	 */
710	ier = serial_in(up, UART_IER);
711	serial_out(up, UART_IER, UART_IER_UUE);
712
713	wait_for_xmitr(up);
714	/*
715	 *	Send the character out.
716	 */
717	serial_out(up, UART_TX, c);
718
719	/*
720	 *	Finally, wait for transmitter to become empty
721	 *	and restore the IER
722	 */
723	wait_for_xmitr(up);
724	serial_out(up, UART_IER, ier);
725}
726
727#endif /* CONFIG_CONSOLE_POLL */
728
729static int __init
730serial_pxa_console_setup(struct console *co, char *options)
731{
732	struct uart_pxa_port *up;
733	int baud = 9600;
734	int bits = 8;
735	int parity = 'n';
736	int flow = 'n';
737
738	if (co->index == -1 || co->index >= serial_pxa_reg.nr)
739		co->index = 0;
740	up = serial_pxa_ports[co->index];
741	if (!up)
742		return -ENODEV;
743
744	if (options)
745		uart_parse_options(options, &baud, &parity, &bits, &flow);
746
747	return uart_set_options(&up->port, co, baud, parity, bits, flow);
748}
749
750static struct console serial_pxa_console = {
751	.name		= "ttyS",
752	.write		= serial_pxa_console_write,
753	.device		= uart_console_device,
754	.setup		= serial_pxa_console_setup,
755	.flags		= CON_PRINTBUFFER,
756	.index		= -1,
757	.data		= &serial_pxa_reg,
758};
759
760#define PXA_CONSOLE	&serial_pxa_console
761#else
762#define PXA_CONSOLE	NULL
763#endif
764
765static struct uart_ops serial_pxa_pops = {
766	.tx_empty	= serial_pxa_tx_empty,
767	.set_mctrl	= serial_pxa_set_mctrl,
768	.get_mctrl	= serial_pxa_get_mctrl,
769	.stop_tx	= serial_pxa_stop_tx,
770	.start_tx	= serial_pxa_start_tx,
771	.stop_rx	= serial_pxa_stop_rx,
772	.enable_ms	= serial_pxa_enable_ms,
773	.break_ctl	= serial_pxa_break_ctl,
774	.startup	= serial_pxa_startup,
775	.shutdown	= serial_pxa_shutdown,
776	.set_termios	= serial_pxa_set_termios,
777	.pm		= serial_pxa_pm,
778	.type		= serial_pxa_type,
779	.release_port	= serial_pxa_release_port,
780	.request_port	= serial_pxa_request_port,
781	.config_port	= serial_pxa_config_port,
782	.verify_port	= serial_pxa_verify_port,
783#if defined(CONFIG_CONSOLE_POLL) && defined(CONFIG_SERIAL_PXA_CONSOLE)
784	.poll_get_char = serial_pxa_get_poll_char,
785	.poll_put_char = serial_pxa_put_poll_char,
786#endif
787};
788
789static struct uart_driver serial_pxa_reg = {
790	.owner		= THIS_MODULE,
791	.driver_name	= "PXA serial",
792	.dev_name	= "ttyS",
793	.major		= TTY_MAJOR,
794	.minor		= 64,
795	.nr		= 4,
796	.cons		= PXA_CONSOLE,
797};
798
799#ifdef CONFIG_PM
800static int serial_pxa_suspend(struct device *dev)
801{
802        struct uart_pxa_port *sport = dev_get_drvdata(dev);
803
804        if (sport)
805                uart_suspend_port(&serial_pxa_reg, &sport->port);
806
807        return 0;
808}
809
810static int serial_pxa_resume(struct device *dev)
811{
812        struct uart_pxa_port *sport = dev_get_drvdata(dev);
813
814        if (sport)
815                uart_resume_port(&serial_pxa_reg, &sport->port);
816
817        return 0;
818}
819
820static const struct dev_pm_ops serial_pxa_pm_ops = {
821	.suspend	= serial_pxa_suspend,
822	.resume		= serial_pxa_resume,
823};
824#endif
825
826static const struct of_device_id serial_pxa_dt_ids[] = {
827	{ .compatible = "mrvl,pxa-uart", },
828	{ .compatible = "mrvl,mmp-uart", },
829	{}
830};
831
832static int serial_pxa_probe_dt(struct platform_device *pdev,
833			       struct uart_pxa_port *sport)
834{
835	struct device_node *np = pdev->dev.of_node;
836	int ret;
837
838	if (!np)
839		return 1;
840
841	ret = of_alias_get_id(np, "serial");
842	if (ret < 0) {
843		dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
844		return ret;
845	}
846	sport->port.line = ret;
847	return 0;
848}
849
850static int serial_pxa_probe(struct platform_device *dev)
851{
852	struct uart_pxa_port *sport;
853	struct resource *mmres, *irqres;
854	int ret;
855
856	mmres = platform_get_resource(dev, IORESOURCE_MEM, 0);
857	irqres = platform_get_resource(dev, IORESOURCE_IRQ, 0);
858	if (!mmres || !irqres)
859		return -ENODEV;
860
861	sport = kzalloc(sizeof(struct uart_pxa_port), GFP_KERNEL);
862	if (!sport)
863		return -ENOMEM;
864
865	sport->clk = clk_get(&dev->dev, NULL);
866	if (IS_ERR(sport->clk)) {
867		ret = PTR_ERR(sport->clk);
868		goto err_free;
869	}
870
871	ret = clk_prepare(sport->clk);
872	if (ret) {
873		clk_put(sport->clk);
874		goto err_free;
875	}
876
877	sport->port.type = PORT_PXA;
878	sport->port.iotype = UPIO_MEM;
879	sport->port.mapbase = mmres->start;
880	sport->port.irq = irqres->start;
881	sport->port.fifosize = 64;
882	sport->port.ops = &serial_pxa_pops;
 
883	sport->port.dev = &dev->dev;
884	sport->port.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF;
885	sport->port.uartclk = clk_get_rate(sport->clk);
886
887	ret = serial_pxa_probe_dt(dev, sport);
888	if (ret > 0)
889		sport->port.line = dev->id;
890	else if (ret < 0)
891		goto err_clk;
892	snprintf(sport->name, PXA_NAME_LEN - 1, "UART%d", sport->port.line + 1);
 
 
 
893
894	sport->port.membase = ioremap(mmres->start, resource_size(mmres));
895	if (!sport->port.membase) {
896		ret = -ENOMEM;
897		goto err_clk;
898	}
899
900	serial_pxa_ports[sport->port.line] = sport;
901
902	uart_add_one_port(&serial_pxa_reg, &sport->port);
903	platform_set_drvdata(dev, sport);
904
905	return 0;
906
907 err_clk:
908	clk_unprepare(sport->clk);
909	clk_put(sport->clk);
910 err_free:
911	kfree(sport);
912	return ret;
913}
914
 
 
 
 
 
 
 
 
 
 
 
 
 
915static struct platform_driver serial_pxa_driver = {
916        .probe          = serial_pxa_probe,
 
917
918	.driver		= {
919	        .name	= "pxa2xx-uart",
 
920#ifdef CONFIG_PM
921		.pm	= &serial_pxa_pm_ops,
922#endif
923		.suppress_bind_attrs = true,
924		.of_match_table = serial_pxa_dt_ids,
925	},
926};
927
928
929/* 8250 driver for PXA serial ports should be used */
930static int __init serial_pxa_init(void)
931{
932	int ret;
933
934	ret = uart_register_driver(&serial_pxa_reg);
935	if (ret != 0)
936		return ret;
937
938	ret = platform_driver_register(&serial_pxa_driver);
939	if (ret != 0)
940		uart_unregister_driver(&serial_pxa_reg);
941
942	return ret;
943}
944device_initcall(serial_pxa_init);