xref: /openbmc/linux/drivers/tty/serial/imx.c (revision 54525552)
1 /*
2  *  Driver for Motorola IMX serial ports
3  *
4  *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
5  *
6  *  Author: Sascha Hauer <sascha@saschahauer.de>
7  *  Copyright (C) 2004 Pengutronix
8  *
9  *  Copyright (C) 2009 emlix GmbH
10  *  Author: Fabian Godehardt (added IrDA support for iMX)
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License as published by
14  * the Free Software Foundation; either version 2 of the License, or
15  * (at your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
25  *
26  * [29-Mar-2005] Mike Lee
27  * Added hardware handshake
28  */
29 
30 #if defined(CONFIG_SERIAL_IMX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
31 #define SUPPORT_SYSRQ
32 #endif
33 
34 #include <linux/module.h>
35 #include <linux/ioport.h>
36 #include <linux/init.h>
37 #include <linux/console.h>
38 #include <linux/sysrq.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/serial.h>
44 #include <linux/clk.h>
45 #include <linux/delay.h>
46 #include <linux/rational.h>
47 #include <linux/slab.h>
48 
49 #include <asm/io.h>
50 #include <asm/irq.h>
51 #include <mach/hardware.h>
52 #include <mach/imx-uart.h>
53 
54 /* Register definitions */
55 #define URXD0 0x0  /* Receiver Register */
56 #define URTX0 0x40 /* Transmitter Register */
57 #define UCR1  0x80 /* Control Register 1 */
58 #define UCR2  0x84 /* Control Register 2 */
59 #define UCR3  0x88 /* Control Register 3 */
60 #define UCR4  0x8c /* Control Register 4 */
61 #define UFCR  0x90 /* FIFO Control Register */
62 #define USR1  0x94 /* Status Register 1 */
63 #define USR2  0x98 /* Status Register 2 */
64 #define UESC  0x9c /* Escape Character Register */
65 #define UTIM  0xa0 /* Escape Timer Register */
66 #define UBIR  0xa4 /* BRM Incremental Register */
67 #define UBMR  0xa8 /* BRM Modulator Register */
68 #define UBRC  0xac /* Baud Rate Count Register */
69 #define MX2_ONEMS 0xb0 /* One Millisecond register */
70 #define UTS (cpu_is_mx1() ? 0xd0 : 0xb4) /* UART Test Register */
71 
72 /* UART Control Register Bit Fields.*/
73 #define  URXD_CHARRDY    (1<<15)
74 #define  URXD_ERR        (1<<14)
75 #define  URXD_OVRRUN     (1<<13)
76 #define  URXD_FRMERR     (1<<12)
77 #define  URXD_BRK        (1<<11)
78 #define  URXD_PRERR      (1<<10)
79 #define  UCR1_ADEN       (1<<15) /* Auto detect interrupt */
80 #define  UCR1_ADBR       (1<<14) /* Auto detect baud rate */
81 #define  UCR1_TRDYEN     (1<<13) /* Transmitter ready interrupt enable */
82 #define  UCR1_IDEN       (1<<12) /* Idle condition interrupt */
83 #define  UCR1_RRDYEN     (1<<9)	 /* Recv ready interrupt enable */
84 #define  UCR1_RDMAEN     (1<<8)	 /* Recv ready DMA enable */
85 #define  UCR1_IREN       (1<<7)	 /* Infrared interface enable */
86 #define  UCR1_TXMPTYEN   (1<<6)	 /* Transimitter empty interrupt enable */
87 #define  UCR1_RTSDEN     (1<<5)	 /* RTS delta interrupt enable */
88 #define  UCR1_SNDBRK     (1<<4)	 /* Send break */
89 #define  UCR1_TDMAEN     (1<<3)	 /* Transmitter ready DMA enable */
90 #define  MX1_UCR1_UARTCLKEN  (1<<2)	 /* UART clock enabled, mx1 only */
91 #define  UCR1_DOZE       (1<<1)	 /* Doze */
92 #define  UCR1_UARTEN     (1<<0)	 /* UART enabled */
93 #define  UCR2_ESCI     	 (1<<15) /* Escape seq interrupt enable */
94 #define  UCR2_IRTS  	 (1<<14) /* Ignore RTS pin */
95 #define  UCR2_CTSC  	 (1<<13) /* CTS pin control */
96 #define  UCR2_CTS        (1<<12) /* Clear to send */
97 #define  UCR2_ESCEN      (1<<11) /* Escape enable */
98 #define  UCR2_PREN       (1<<8)  /* Parity enable */
99 #define  UCR2_PROE       (1<<7)  /* Parity odd/even */
100 #define  UCR2_STPB       (1<<6)	 /* Stop */
101 #define  UCR2_WS         (1<<5)	 /* Word size */
102 #define  UCR2_RTSEN      (1<<4)	 /* Request to send interrupt enable */
103 #define  UCR2_TXEN       (1<<2)	 /* Transmitter enabled */
104 #define  UCR2_RXEN       (1<<1)	 /* Receiver enabled */
105 #define  UCR2_SRST 	 (1<<0)	 /* SW reset */
106 #define  UCR3_DTREN 	 (1<<13) /* DTR interrupt enable */
107 #define  UCR3_PARERREN   (1<<12) /* Parity enable */
108 #define  UCR3_FRAERREN   (1<<11) /* Frame error interrupt enable */
109 #define  UCR3_DSR        (1<<10) /* Data set ready */
110 #define  UCR3_DCD        (1<<9)  /* Data carrier detect */
111 #define  UCR3_RI         (1<<8)  /* Ring indicator */
112 #define  UCR3_TIMEOUTEN  (1<<7)  /* Timeout interrupt enable */
113 #define  UCR3_RXDSEN	 (1<<6)  /* Receive status interrupt enable */
114 #define  UCR3_AIRINTEN   (1<<5)  /* Async IR wake interrupt enable */
115 #define  UCR3_AWAKEN	 (1<<4)  /* Async wake interrupt enable */
116 #define  MX1_UCR3_REF25 	 (1<<3)  /* Ref freq 25 MHz, only on mx1 */
117 #define  MX1_UCR3_REF30 	 (1<<2)  /* Ref Freq 30 MHz, only on mx1 */
118 #define  MX2_UCR3_RXDMUXSEL	 (1<<2)  /* RXD Muxed Input Select, on mx2/mx3 */
119 #define  UCR3_INVT  	 (1<<1)  /* Inverted Infrared transmission */
120 #define  UCR3_BPEN  	 (1<<0)  /* Preset registers enable */
121 #define  UCR4_CTSTL_SHF  10      /* CTS trigger level shift */
122 #define  UCR4_CTSTL_MASK 0x3F    /* CTS trigger is 6 bits wide */
123 #define  UCR4_INVR  	 (1<<9)  /* Inverted infrared reception */
124 #define  UCR4_ENIRI 	 (1<<8)  /* Serial infrared interrupt enable */
125 #define  UCR4_WKEN  	 (1<<7)  /* Wake interrupt enable */
126 #define  UCR4_REF16 	 (1<<6)  /* Ref freq 16 MHz */
127 #define  UCR4_IRSC  	 (1<<5)  /* IR special case */
128 #define  UCR4_TCEN  	 (1<<3)  /* Transmit complete interrupt enable */
129 #define  UCR4_BKEN  	 (1<<2)  /* Break condition interrupt enable */
130 #define  UCR4_OREN  	 (1<<1)  /* Receiver overrun interrupt enable */
131 #define  UCR4_DREN  	 (1<<0)  /* Recv data ready interrupt enable */
132 #define  UFCR_RXTL_SHF   0       /* Receiver trigger level shift */
133 #define  UFCR_RFDIV      (7<<7)  /* Reference freq divider mask */
134 #define  UFCR_RFDIV_REG(x)	(((x) < 7 ? 6 - (x) : 6) << 7)
135 #define  UFCR_TXTL_SHF   10      /* Transmitter trigger level shift */
136 #define  USR1_PARITYERR  (1<<15) /* Parity error interrupt flag */
137 #define  USR1_RTSS  	 (1<<14) /* RTS pin status */
138 #define  USR1_TRDY  	 (1<<13) /* Transmitter ready interrupt/dma flag */
139 #define  USR1_RTSD  	 (1<<12) /* RTS delta */
140 #define  USR1_ESCF  	 (1<<11) /* Escape seq interrupt flag */
141 #define  USR1_FRAMERR    (1<<10) /* Frame error interrupt flag */
142 #define  USR1_RRDY       (1<<9)	 /* Receiver ready interrupt/dma flag */
143 #define  USR1_TIMEOUT    (1<<7)	 /* Receive timeout interrupt status */
144 #define  USR1_RXDS  	 (1<<6)	 /* Receiver idle interrupt flag */
145 #define  USR1_AIRINT	 (1<<5)	 /* Async IR wake interrupt flag */
146 #define  USR1_AWAKE 	 (1<<4)	 /* Aysnc wake interrupt flag */
147 #define  USR2_ADET  	 (1<<15) /* Auto baud rate detect complete */
148 #define  USR2_TXFE  	 (1<<14) /* Transmit buffer FIFO empty */
149 #define  USR2_DTRF  	 (1<<13) /* DTR edge interrupt flag */
150 #define  USR2_IDLE  	 (1<<12) /* Idle condition */
151 #define  USR2_IRINT 	 (1<<8)	 /* Serial infrared interrupt flag */
152 #define  USR2_WAKE  	 (1<<7)	 /* Wake */
153 #define  USR2_RTSF  	 (1<<4)	 /* RTS edge interrupt flag */
154 #define  USR2_TXDC  	 (1<<3)	 /* Transmitter complete */
155 #define  USR2_BRCD  	 (1<<2)	 /* Break condition */
156 #define  USR2_ORE        (1<<1)	 /* Overrun error */
157 #define  USR2_RDR        (1<<0)	 /* Recv data ready */
158 #define  UTS_FRCPERR	 (1<<13) /* Force parity error */
159 #define  UTS_LOOP        (1<<12) /* Loop tx and rx */
160 #define  UTS_TXEMPTY	 (1<<6)	 /* TxFIFO empty */
161 #define  UTS_RXEMPTY	 (1<<5)	 /* RxFIFO empty */
162 #define  UTS_TXFULL 	 (1<<4)	 /* TxFIFO full */
163 #define  UTS_RXFULL 	 (1<<3)	 /* RxFIFO full */
164 #define  UTS_SOFTRST	 (1<<0)	 /* Software reset */
165 
166 /* We've been assigned a range on the "Low-density serial ports" major */
167 #define SERIAL_IMX_MAJOR        207
168 #define MINOR_START	        16
169 #define DEV_NAME		"ttymxc"
170 #define MAX_INTERNAL_IRQ	MXC_INTERNAL_IRQS
171 
172 /*
173  * This determines how often we check the modem status signals
174  * for any change.  They generally aren't connected to an IRQ
175  * so we have to poll them.  We also check immediately before
176  * filling the TX fifo incase CTS has been dropped.
177  */
178 #define MCTRL_TIMEOUT	(250*HZ/1000)
179 
180 #define DRIVER_NAME "IMX-uart"
181 
182 #define UART_NR 8
183 
184 struct imx_port {
185 	struct uart_port	port;
186 	struct timer_list	timer;
187 	unsigned int		old_status;
188 	int			txirq,rxirq,rtsirq;
189 	unsigned int		have_rtscts:1;
190 	unsigned int		use_irda:1;
191 	unsigned int		irda_inv_rx:1;
192 	unsigned int		irda_inv_tx:1;
193 	unsigned short		trcv_delay; /* transceiver delay */
194 	struct clk		*clk;
195 };
196 
197 #ifdef CONFIG_IRDA
198 #define USE_IRDA(sport)	((sport)->use_irda)
199 #else
200 #define USE_IRDA(sport)	(0)
201 #endif
202 
203 /*
204  * Handle any change of modem status signal since we were last called.
205  */
206 static void imx_mctrl_check(struct imx_port *sport)
207 {
208 	unsigned int status, changed;
209 
210 	status = sport->port.ops->get_mctrl(&sport->port);
211 	changed = status ^ sport->old_status;
212 
213 	if (changed == 0)
214 		return;
215 
216 	sport->old_status = status;
217 
218 	if (changed & TIOCM_RI)
219 		sport->port.icount.rng++;
220 	if (changed & TIOCM_DSR)
221 		sport->port.icount.dsr++;
222 	if (changed & TIOCM_CAR)
223 		uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
224 	if (changed & TIOCM_CTS)
225 		uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
226 
227 	wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
228 }
229 
230 /*
231  * This is our per-port timeout handler, for checking the
232  * modem status signals.
233  */
234 static void imx_timeout(unsigned long data)
235 {
236 	struct imx_port *sport = (struct imx_port *)data;
237 	unsigned long flags;
238 
239 	if (sport->port.state) {
240 		spin_lock_irqsave(&sport->port.lock, flags);
241 		imx_mctrl_check(sport);
242 		spin_unlock_irqrestore(&sport->port.lock, flags);
243 
244 		mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
245 	}
246 }
247 
248 /*
249  * interrupts disabled on entry
250  */
251 static void imx_stop_tx(struct uart_port *port)
252 {
253 	struct imx_port *sport = (struct imx_port *)port;
254 	unsigned long temp;
255 
256 	if (USE_IRDA(sport)) {
257 		/* half duplex - wait for end of transmission */
258 		int n = 256;
259 		while ((--n > 0) &&
260 		      !(readl(sport->port.membase + USR2) & USR2_TXDC)) {
261 			udelay(5);
262 			barrier();
263 		}
264 		/*
265 		 * irda transceiver - wait a bit more to avoid
266 		 * cutoff, hardware dependent
267 		 */
268 		udelay(sport->trcv_delay);
269 
270 		/*
271 		 * half duplex - reactivate receive mode,
272 		 * flush receive pipe echo crap
273 		 */
274 		if (readl(sport->port.membase + USR2) & USR2_TXDC) {
275 			temp = readl(sport->port.membase + UCR1);
276 			temp &= ~(UCR1_TXMPTYEN | UCR1_TRDYEN);
277 			writel(temp, sport->port.membase + UCR1);
278 
279 			temp = readl(sport->port.membase + UCR4);
280 			temp &= ~(UCR4_TCEN);
281 			writel(temp, sport->port.membase + UCR4);
282 
283 			while (readl(sport->port.membase + URXD0) &
284 			       URXD_CHARRDY)
285 				barrier();
286 
287 			temp = readl(sport->port.membase + UCR1);
288 			temp |= UCR1_RRDYEN;
289 			writel(temp, sport->port.membase + UCR1);
290 
291 			temp = readl(sport->port.membase + UCR4);
292 			temp |= UCR4_DREN;
293 			writel(temp, sport->port.membase + UCR4);
294 		}
295 		return;
296 	}
297 
298 	temp = readl(sport->port.membase + UCR1);
299 	writel(temp & ~UCR1_TXMPTYEN, sport->port.membase + UCR1);
300 }
301 
302 /*
303  * interrupts disabled on entry
304  */
305 static void imx_stop_rx(struct uart_port *port)
306 {
307 	struct imx_port *sport = (struct imx_port *)port;
308 	unsigned long temp;
309 
310 	temp = readl(sport->port.membase + UCR2);
311 	writel(temp &~ UCR2_RXEN, sport->port.membase + UCR2);
312 }
313 
314 /*
315  * Set the modem control timer to fire immediately.
316  */
317 static void imx_enable_ms(struct uart_port *port)
318 {
319 	struct imx_port *sport = (struct imx_port *)port;
320 
321 	mod_timer(&sport->timer, jiffies);
322 }
323 
324 static inline void imx_transmit_buffer(struct imx_port *sport)
325 {
326 	struct circ_buf *xmit = &sport->port.state->xmit;
327 
328 	while (!uart_circ_empty(xmit) &&
329 			!(readl(sport->port.membase + UTS) & UTS_TXFULL)) {
330 		/* send xmit->buf[xmit->tail]
331 		 * out the port here */
332 		writel(xmit->buf[xmit->tail], sport->port.membase + URTX0);
333 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
334 		sport->port.icount.tx++;
335 	}
336 
337 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
338 		uart_write_wakeup(&sport->port);
339 
340 	if (uart_circ_empty(xmit))
341 		imx_stop_tx(&sport->port);
342 }
343 
344 /*
345  * interrupts disabled on entry
346  */
347 static void imx_start_tx(struct uart_port *port)
348 {
349 	struct imx_port *sport = (struct imx_port *)port;
350 	unsigned long temp;
351 
352 	if (USE_IRDA(sport)) {
353 		/* half duplex in IrDA mode; have to disable receive mode */
354 		temp = readl(sport->port.membase + UCR4);
355 		temp &= ~(UCR4_DREN);
356 		writel(temp, sport->port.membase + UCR4);
357 
358 		temp = readl(sport->port.membase + UCR1);
359 		temp &= ~(UCR1_RRDYEN);
360 		writel(temp, sport->port.membase + UCR1);
361 	}
362 
363 	temp = readl(sport->port.membase + UCR1);
364 	writel(temp | UCR1_TXMPTYEN, sport->port.membase + UCR1);
365 
366 	if (USE_IRDA(sport)) {
367 		temp = readl(sport->port.membase + UCR1);
368 		temp |= UCR1_TRDYEN;
369 		writel(temp, sport->port.membase + UCR1);
370 
371 		temp = readl(sport->port.membase + UCR4);
372 		temp |= UCR4_TCEN;
373 		writel(temp, sport->port.membase + UCR4);
374 	}
375 
376 	if (readl(sport->port.membase + UTS) & UTS_TXEMPTY)
377 		imx_transmit_buffer(sport);
378 }
379 
380 static irqreturn_t imx_rtsint(int irq, void *dev_id)
381 {
382 	struct imx_port *sport = dev_id;
383 	unsigned int val;
384 	unsigned long flags;
385 
386 	spin_lock_irqsave(&sport->port.lock, flags);
387 
388 	writel(USR1_RTSD, sport->port.membase + USR1);
389 	val = readl(sport->port.membase + USR1) & USR1_RTSS;
390 	uart_handle_cts_change(&sport->port, !!val);
391 	wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
392 
393 	spin_unlock_irqrestore(&sport->port.lock, flags);
394 	return IRQ_HANDLED;
395 }
396 
397 static irqreturn_t imx_txint(int irq, void *dev_id)
398 {
399 	struct imx_port *sport = dev_id;
400 	struct circ_buf *xmit = &sport->port.state->xmit;
401 	unsigned long flags;
402 
403 	spin_lock_irqsave(&sport->port.lock,flags);
404 	if (sport->port.x_char)
405 	{
406 		/* Send next char */
407 		writel(sport->port.x_char, sport->port.membase + URTX0);
408 		goto out;
409 	}
410 
411 	if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
412 		imx_stop_tx(&sport->port);
413 		goto out;
414 	}
415 
416 	imx_transmit_buffer(sport);
417 
418 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
419 		uart_write_wakeup(&sport->port);
420 
421 out:
422 	spin_unlock_irqrestore(&sport->port.lock,flags);
423 	return IRQ_HANDLED;
424 }
425 
426 static irqreturn_t imx_rxint(int irq, void *dev_id)
427 {
428 	struct imx_port *sport = dev_id;
429 	unsigned int rx,flg,ignored = 0;
430 	struct tty_struct *tty = sport->port.state->port.tty;
431 	unsigned long flags, temp;
432 
433 	spin_lock_irqsave(&sport->port.lock,flags);
434 
435 	while (readl(sport->port.membase + USR2) & USR2_RDR) {
436 		flg = TTY_NORMAL;
437 		sport->port.icount.rx++;
438 
439 		rx = readl(sport->port.membase + URXD0);
440 
441 		temp = readl(sport->port.membase + USR2);
442 		if (temp & USR2_BRCD) {
443 			writel(USR2_BRCD, sport->port.membase + USR2);
444 			if (uart_handle_break(&sport->port))
445 				continue;
446 		}
447 
448 		if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx))
449 			continue;
450 
451 		if (rx & (URXD_PRERR | URXD_OVRRUN | URXD_FRMERR) ) {
452 			if (rx & URXD_PRERR)
453 				sport->port.icount.parity++;
454 			else if (rx & URXD_FRMERR)
455 				sport->port.icount.frame++;
456 			if (rx & URXD_OVRRUN)
457 				sport->port.icount.overrun++;
458 
459 			if (rx & sport->port.ignore_status_mask) {
460 				if (++ignored > 100)
461 					goto out;
462 				continue;
463 			}
464 
465 			rx &= sport->port.read_status_mask;
466 
467 			if (rx & URXD_PRERR)
468 				flg = TTY_PARITY;
469 			else if (rx & URXD_FRMERR)
470 				flg = TTY_FRAME;
471 			if (rx & URXD_OVRRUN)
472 				flg = TTY_OVERRUN;
473 
474 #ifdef SUPPORT_SYSRQ
475 			sport->port.sysrq = 0;
476 #endif
477 		}
478 
479 		tty_insert_flip_char(tty, rx, flg);
480 	}
481 
482 out:
483 	spin_unlock_irqrestore(&sport->port.lock,flags);
484 	tty_flip_buffer_push(tty);
485 	return IRQ_HANDLED;
486 }
487 
488 static irqreturn_t imx_int(int irq, void *dev_id)
489 {
490 	struct imx_port *sport = dev_id;
491 	unsigned int sts;
492 
493 	sts = readl(sport->port.membase + USR1);
494 
495 	if (sts & USR1_RRDY)
496 		imx_rxint(irq, dev_id);
497 
498 	if (sts & USR1_TRDY &&
499 			readl(sport->port.membase + UCR1) & UCR1_TXMPTYEN)
500 		imx_txint(irq, dev_id);
501 
502 	if (sts & USR1_RTSD)
503 		imx_rtsint(irq, dev_id);
504 
505 	return IRQ_HANDLED;
506 }
507 
508 /*
509  * Return TIOCSER_TEMT when transmitter is not busy.
510  */
511 static unsigned int imx_tx_empty(struct uart_port *port)
512 {
513 	struct imx_port *sport = (struct imx_port *)port;
514 
515 	return (readl(sport->port.membase + USR2) & USR2_TXDC) ?  TIOCSER_TEMT : 0;
516 }
517 
518 /*
519  * We have a modem side uart, so the meanings of RTS and CTS are inverted.
520  */
521 static unsigned int imx_get_mctrl(struct uart_port *port)
522 {
523 	struct imx_port *sport = (struct imx_port *)port;
524 	unsigned int tmp = TIOCM_DSR | TIOCM_CAR;
525 
526 	if (readl(sport->port.membase + USR1) & USR1_RTSS)
527 		tmp |= TIOCM_CTS;
528 
529 	if (readl(sport->port.membase + UCR2) & UCR2_CTS)
530 		tmp |= TIOCM_RTS;
531 
532 	return tmp;
533 }
534 
535 static void imx_set_mctrl(struct uart_port *port, unsigned int mctrl)
536 {
537 	struct imx_port *sport = (struct imx_port *)port;
538 	unsigned long temp;
539 
540 	temp = readl(sport->port.membase + UCR2) & ~UCR2_CTS;
541 
542 	if (mctrl & TIOCM_RTS)
543 		temp |= UCR2_CTS;
544 
545 	writel(temp, sport->port.membase + UCR2);
546 }
547 
548 /*
549  * Interrupts always disabled.
550  */
551 static void imx_break_ctl(struct uart_port *port, int break_state)
552 {
553 	struct imx_port *sport = (struct imx_port *)port;
554 	unsigned long flags, temp;
555 
556 	spin_lock_irqsave(&sport->port.lock, flags);
557 
558 	temp = readl(sport->port.membase + UCR1) & ~UCR1_SNDBRK;
559 
560 	if ( break_state != 0 )
561 		temp |= UCR1_SNDBRK;
562 
563 	writel(temp, sport->port.membase + UCR1);
564 
565 	spin_unlock_irqrestore(&sport->port.lock, flags);
566 }
567 
568 #define TXTL 2 /* reset default */
569 #define RXTL 1 /* reset default */
570 
571 static int imx_setup_ufcr(struct imx_port *sport, unsigned int mode)
572 {
573 	unsigned int val;
574 	unsigned int ufcr_rfdiv;
575 
576 	/* set receiver / transmitter trigger level.
577 	 * RFDIV is set such way to satisfy requested uartclk value
578 	 */
579 	val = TXTL << 10 | RXTL;
580 	ufcr_rfdiv = (clk_get_rate(sport->clk) + sport->port.uartclk / 2)
581 			/ sport->port.uartclk;
582 
583 	if(!ufcr_rfdiv)
584 		ufcr_rfdiv = 1;
585 
586 	val |= UFCR_RFDIV_REG(ufcr_rfdiv);
587 
588 	writel(val, sport->port.membase + UFCR);
589 
590 	return 0;
591 }
592 
593 /* half the RX buffer size */
594 #define CTSTL 16
595 
596 static int imx_startup(struct uart_port *port)
597 {
598 	struct imx_port *sport = (struct imx_port *)port;
599 	int retval;
600 	unsigned long flags, temp;
601 
602 	imx_setup_ufcr(sport, 0);
603 
604 	/* disable the DREN bit (Data Ready interrupt enable) before
605 	 * requesting IRQs
606 	 */
607 	temp = readl(sport->port.membase + UCR4);
608 
609 	if (USE_IRDA(sport))
610 		temp |= UCR4_IRSC;
611 
612 	/* set the trigger level for CTS */
613 	temp &= ~(UCR4_CTSTL_MASK<<  UCR4_CTSTL_SHF);
614 	temp |= CTSTL<<  UCR4_CTSTL_SHF;
615 
616 	writel(temp & ~UCR4_DREN, sport->port.membase + UCR4);
617 
618 	if (USE_IRDA(sport)) {
619 		/* reset fifo's and state machines */
620 		int i = 100;
621 		temp = readl(sport->port.membase + UCR2);
622 		temp &= ~UCR2_SRST;
623 		writel(temp, sport->port.membase + UCR2);
624 		while (!(readl(sport->port.membase + UCR2) & UCR2_SRST) &&
625 		    (--i > 0)) {
626 			udelay(1);
627 		}
628 	}
629 
630 	/*
631 	 * Allocate the IRQ(s) i.MX1 has three interrupts whereas later
632 	 * chips only have one interrupt.
633 	 */
634 	if (sport->txirq > 0) {
635 		retval = request_irq(sport->rxirq, imx_rxint, 0,
636 				DRIVER_NAME, sport);
637 		if (retval)
638 			goto error_out1;
639 
640 		retval = request_irq(sport->txirq, imx_txint, 0,
641 				DRIVER_NAME, sport);
642 		if (retval)
643 			goto error_out2;
644 
645 		/* do not use RTS IRQ on IrDA */
646 		if (!USE_IRDA(sport)) {
647 			retval = request_irq(sport->rtsirq, imx_rtsint,
648 				     (sport->rtsirq < MAX_INTERNAL_IRQ) ? 0 :
649 				       IRQF_TRIGGER_FALLING |
650 				       IRQF_TRIGGER_RISING,
651 					DRIVER_NAME, sport);
652 			if (retval)
653 				goto error_out3;
654 		}
655 	} else {
656 		retval = request_irq(sport->port.irq, imx_int, 0,
657 				DRIVER_NAME, sport);
658 		if (retval) {
659 			free_irq(sport->port.irq, sport);
660 			goto error_out1;
661 		}
662 	}
663 
664 	/*
665 	 * Finally, clear and enable interrupts
666 	 */
667 	writel(USR1_RTSD, sport->port.membase + USR1);
668 
669 	temp = readl(sport->port.membase + UCR1);
670 	temp |= UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN;
671 
672 	if (USE_IRDA(sport)) {
673 		temp |= UCR1_IREN;
674 		temp &= ~(UCR1_RTSDEN);
675 	}
676 
677 	writel(temp, sport->port.membase + UCR1);
678 
679 	temp = readl(sport->port.membase + UCR2);
680 	temp |= (UCR2_RXEN | UCR2_TXEN);
681 	writel(temp, sport->port.membase + UCR2);
682 
683 	if (USE_IRDA(sport)) {
684 		/* clear RX-FIFO */
685 		int i = 64;
686 		while ((--i > 0) &&
687 			(readl(sport->port.membase + URXD0) & URXD_CHARRDY)) {
688 			barrier();
689 		}
690 	}
691 
692 	if (!cpu_is_mx1()) {
693 		temp = readl(sport->port.membase + UCR3);
694 		temp |= MX2_UCR3_RXDMUXSEL;
695 		writel(temp, sport->port.membase + UCR3);
696 	}
697 
698 	if (USE_IRDA(sport)) {
699 		temp = readl(sport->port.membase + UCR4);
700 		if (sport->irda_inv_rx)
701 			temp |= UCR4_INVR;
702 		else
703 			temp &= ~(UCR4_INVR);
704 		writel(temp | UCR4_DREN, sport->port.membase + UCR4);
705 
706 		temp = readl(sport->port.membase + UCR3);
707 		if (sport->irda_inv_tx)
708 			temp |= UCR3_INVT;
709 		else
710 			temp &= ~(UCR3_INVT);
711 		writel(temp, sport->port.membase + UCR3);
712 	}
713 
714 	/*
715 	 * Enable modem status interrupts
716 	 */
717 	spin_lock_irqsave(&sport->port.lock,flags);
718 	imx_enable_ms(&sport->port);
719 	spin_unlock_irqrestore(&sport->port.lock,flags);
720 
721 	if (USE_IRDA(sport)) {
722 		struct imxuart_platform_data *pdata;
723 		pdata = sport->port.dev->platform_data;
724 		sport->irda_inv_rx = pdata->irda_inv_rx;
725 		sport->irda_inv_tx = pdata->irda_inv_tx;
726 		sport->trcv_delay = pdata->transceiver_delay;
727 		if (pdata->irda_enable)
728 			pdata->irda_enable(1);
729 	}
730 
731 	return 0;
732 
733 error_out3:
734 	if (sport->txirq)
735 		free_irq(sport->txirq, sport);
736 error_out2:
737 	if (sport->rxirq)
738 		free_irq(sport->rxirq, sport);
739 error_out1:
740 	return retval;
741 }
742 
743 static void imx_shutdown(struct uart_port *port)
744 {
745 	struct imx_port *sport = (struct imx_port *)port;
746 	unsigned long temp;
747 
748 	temp = readl(sport->port.membase + UCR2);
749 	temp &= ~(UCR2_TXEN);
750 	writel(temp, sport->port.membase + UCR2);
751 
752 	if (USE_IRDA(sport)) {
753 		struct imxuart_platform_data *pdata;
754 		pdata = sport->port.dev->platform_data;
755 		if (pdata->irda_enable)
756 			pdata->irda_enable(0);
757 	}
758 
759 	/*
760 	 * Stop our timer.
761 	 */
762 	del_timer_sync(&sport->timer);
763 
764 	/*
765 	 * Free the interrupts
766 	 */
767 	if (sport->txirq > 0) {
768 		if (!USE_IRDA(sport))
769 			free_irq(sport->rtsirq, sport);
770 		free_irq(sport->txirq, sport);
771 		free_irq(sport->rxirq, sport);
772 	} else
773 		free_irq(sport->port.irq, sport);
774 
775 	/*
776 	 * Disable all interrupts, port and break condition.
777 	 */
778 
779 	temp = readl(sport->port.membase + UCR1);
780 	temp &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN);
781 	if (USE_IRDA(sport))
782 		temp &= ~(UCR1_IREN);
783 
784 	writel(temp, sport->port.membase + UCR1);
785 }
786 
787 static void
788 imx_set_termios(struct uart_port *port, struct ktermios *termios,
789 		   struct ktermios *old)
790 {
791 	struct imx_port *sport = (struct imx_port *)port;
792 	unsigned long flags;
793 	unsigned int ucr2, old_ucr1, old_txrxen, baud, quot;
794 	unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
795 	unsigned int div, ufcr;
796 	unsigned long num, denom;
797 	uint64_t tdiv64;
798 
799 	/*
800 	 * If we don't support modem control lines, don't allow
801 	 * these to be set.
802 	 */
803 	if (0) {
804 		termios->c_cflag &= ~(HUPCL | CRTSCTS | CMSPAR);
805 		termios->c_cflag |= CLOCAL;
806 	}
807 
808 	/*
809 	 * We only support CS7 and CS8.
810 	 */
811 	while ((termios->c_cflag & CSIZE) != CS7 &&
812 	       (termios->c_cflag & CSIZE) != CS8) {
813 		termios->c_cflag &= ~CSIZE;
814 		termios->c_cflag |= old_csize;
815 		old_csize = CS8;
816 	}
817 
818 	if ((termios->c_cflag & CSIZE) == CS8)
819 		ucr2 = UCR2_WS | UCR2_SRST | UCR2_IRTS;
820 	else
821 		ucr2 = UCR2_SRST | UCR2_IRTS;
822 
823 	if (termios->c_cflag & CRTSCTS) {
824 		if( sport->have_rtscts ) {
825 			ucr2 &= ~UCR2_IRTS;
826 			ucr2 |= UCR2_CTSC;
827 		} else {
828 			termios->c_cflag &= ~CRTSCTS;
829 		}
830 	}
831 
832 	if (termios->c_cflag & CSTOPB)
833 		ucr2 |= UCR2_STPB;
834 	if (termios->c_cflag & PARENB) {
835 		ucr2 |= UCR2_PREN;
836 		if (termios->c_cflag & PARODD)
837 			ucr2 |= UCR2_PROE;
838 	}
839 
840 	/*
841 	 * Ask the core to calculate the divisor for us.
842 	 */
843 	baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
844 	quot = uart_get_divisor(port, baud);
845 
846 	spin_lock_irqsave(&sport->port.lock, flags);
847 
848 	sport->port.read_status_mask = 0;
849 	if (termios->c_iflag & INPCK)
850 		sport->port.read_status_mask |= (URXD_FRMERR | URXD_PRERR);
851 	if (termios->c_iflag & (BRKINT | PARMRK))
852 		sport->port.read_status_mask |= URXD_BRK;
853 
854 	/*
855 	 * Characters to ignore
856 	 */
857 	sport->port.ignore_status_mask = 0;
858 	if (termios->c_iflag & IGNPAR)
859 		sport->port.ignore_status_mask |= URXD_PRERR;
860 	if (termios->c_iflag & IGNBRK) {
861 		sport->port.ignore_status_mask |= URXD_BRK;
862 		/*
863 		 * If we're ignoring parity and break indicators,
864 		 * ignore overruns too (for real raw support).
865 		 */
866 		if (termios->c_iflag & IGNPAR)
867 			sport->port.ignore_status_mask |= URXD_OVRRUN;
868 	}
869 
870 	del_timer_sync(&sport->timer);
871 
872 	/*
873 	 * Update the per-port timeout.
874 	 */
875 	uart_update_timeout(port, termios->c_cflag, baud);
876 
877 	/*
878 	 * disable interrupts and drain transmitter
879 	 */
880 	old_ucr1 = readl(sport->port.membase + UCR1);
881 	writel(old_ucr1 & ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN),
882 			sport->port.membase + UCR1);
883 
884 	while ( !(readl(sport->port.membase + USR2) & USR2_TXDC))
885 		barrier();
886 
887 	/* then, disable everything */
888 	old_txrxen = readl(sport->port.membase + UCR2);
889 	writel(old_txrxen & ~( UCR2_TXEN | UCR2_RXEN),
890 			sport->port.membase + UCR2);
891 	old_txrxen &= (UCR2_TXEN | UCR2_RXEN);
892 
893 	if (USE_IRDA(sport)) {
894 		/*
895 		 * use maximum available submodule frequency to
896 		 * avoid missing short pulses due to low sampling rate
897 		 */
898 		div = 1;
899 	} else {
900 		div = sport->port.uartclk / (baud * 16);
901 		if (div > 7)
902 			div = 7;
903 		if (!div)
904 			div = 1;
905 	}
906 
907 	rational_best_approximation(16 * div * baud, sport->port.uartclk,
908 		1 << 16, 1 << 16, &num, &denom);
909 
910 	tdiv64 = sport->port.uartclk;
911 	tdiv64 *= num;
912 	do_div(tdiv64, denom * 16 * div);
913 	tty_termios_encode_baud_rate(termios,
914 				(speed_t)tdiv64, (speed_t)tdiv64);
915 
916 	num -= 1;
917 	denom -= 1;
918 
919 	ufcr = readl(sport->port.membase + UFCR);
920 	ufcr = (ufcr & (~UFCR_RFDIV)) | UFCR_RFDIV_REG(div);
921 	writel(ufcr, sport->port.membase + UFCR);
922 
923 	writel(num, sport->port.membase + UBIR);
924 	writel(denom, sport->port.membase + UBMR);
925 
926 	if (!cpu_is_mx1())
927 		writel(sport->port.uartclk / div / 1000,
928 				sport->port.membase + MX2_ONEMS);
929 
930 	writel(old_ucr1, sport->port.membase + UCR1);
931 
932 	/* set the parity, stop bits and data size */
933 	writel(ucr2 | old_txrxen, sport->port.membase + UCR2);
934 
935 	if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
936 		imx_enable_ms(&sport->port);
937 
938 	spin_unlock_irqrestore(&sport->port.lock, flags);
939 }
940 
941 static const char *imx_type(struct uart_port *port)
942 {
943 	struct imx_port *sport = (struct imx_port *)port;
944 
945 	return sport->port.type == PORT_IMX ? "IMX" : NULL;
946 }
947 
948 /*
949  * Release the memory region(s) being used by 'port'.
950  */
951 static void imx_release_port(struct uart_port *port)
952 {
953 	struct platform_device *pdev = to_platform_device(port->dev);
954 	struct resource *mmres;
955 
956 	mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
957 	release_mem_region(mmres->start, mmres->end - mmres->start + 1);
958 }
959 
960 /*
961  * Request the memory region(s) being used by 'port'.
962  */
963 static int imx_request_port(struct uart_port *port)
964 {
965 	struct platform_device *pdev = to_platform_device(port->dev);
966 	struct resource *mmres;
967 	void *ret;
968 
969 	mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
970 	if (!mmres)
971 		return -ENODEV;
972 
973 	ret = request_mem_region(mmres->start, mmres->end - mmres->start + 1,
974 			"imx-uart");
975 
976 	return  ret ? 0 : -EBUSY;
977 }
978 
979 /*
980  * Configure/autoconfigure the port.
981  */
982 static void imx_config_port(struct uart_port *port, int flags)
983 {
984 	struct imx_port *sport = (struct imx_port *)port;
985 
986 	if (flags & UART_CONFIG_TYPE &&
987 	    imx_request_port(&sport->port) == 0)
988 		sport->port.type = PORT_IMX;
989 }
990 
991 /*
992  * Verify the new serial_struct (for TIOCSSERIAL).
993  * The only change we allow are to the flags and type, and
994  * even then only between PORT_IMX and PORT_UNKNOWN
995  */
996 static int
997 imx_verify_port(struct uart_port *port, struct serial_struct *ser)
998 {
999 	struct imx_port *sport = (struct imx_port *)port;
1000 	int ret = 0;
1001 
1002 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_IMX)
1003 		ret = -EINVAL;
1004 	if (sport->port.irq != ser->irq)
1005 		ret = -EINVAL;
1006 	if (ser->io_type != UPIO_MEM)
1007 		ret = -EINVAL;
1008 	if (sport->port.uartclk / 16 != ser->baud_base)
1009 		ret = -EINVAL;
1010 	if ((void *)sport->port.mapbase != ser->iomem_base)
1011 		ret = -EINVAL;
1012 	if (sport->port.iobase != ser->port)
1013 		ret = -EINVAL;
1014 	if (ser->hub6 != 0)
1015 		ret = -EINVAL;
1016 	return ret;
1017 }
1018 
1019 static struct uart_ops imx_pops = {
1020 	.tx_empty	= imx_tx_empty,
1021 	.set_mctrl	= imx_set_mctrl,
1022 	.get_mctrl	= imx_get_mctrl,
1023 	.stop_tx	= imx_stop_tx,
1024 	.start_tx	= imx_start_tx,
1025 	.stop_rx	= imx_stop_rx,
1026 	.enable_ms	= imx_enable_ms,
1027 	.break_ctl	= imx_break_ctl,
1028 	.startup	= imx_startup,
1029 	.shutdown	= imx_shutdown,
1030 	.set_termios	= imx_set_termios,
1031 	.type		= imx_type,
1032 	.release_port	= imx_release_port,
1033 	.request_port	= imx_request_port,
1034 	.config_port	= imx_config_port,
1035 	.verify_port	= imx_verify_port,
1036 };
1037 
1038 static struct imx_port *imx_ports[UART_NR];
1039 
1040 #ifdef CONFIG_SERIAL_IMX_CONSOLE
1041 static void imx_console_putchar(struct uart_port *port, int ch)
1042 {
1043 	struct imx_port *sport = (struct imx_port *)port;
1044 
1045 	while (readl(sport->port.membase + UTS) & UTS_TXFULL)
1046 		barrier();
1047 
1048 	writel(ch, sport->port.membase + URTX0);
1049 }
1050 
1051 /*
1052  * Interrupts are disabled on entering
1053  */
1054 static void
1055 imx_console_write(struct console *co, const char *s, unsigned int count)
1056 {
1057 	struct imx_port *sport = imx_ports[co->index];
1058 	unsigned int old_ucr1, old_ucr2, ucr1;
1059 
1060 	/*
1061 	 *	First, save UCR1/2 and then disable interrupts
1062 	 */
1063 	ucr1 = old_ucr1 = readl(sport->port.membase + UCR1);
1064 	old_ucr2 = readl(sport->port.membase + UCR2);
1065 
1066 	if (cpu_is_mx1())
1067 		ucr1 |= MX1_UCR1_UARTCLKEN;
1068 	ucr1 |= UCR1_UARTEN;
1069 	ucr1 &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN);
1070 
1071 	writel(ucr1, sport->port.membase + UCR1);
1072 
1073 	writel(old_ucr2 | UCR2_TXEN, sport->port.membase + UCR2);
1074 
1075 	uart_console_write(&sport->port, s, count, imx_console_putchar);
1076 
1077 	/*
1078 	 *	Finally, wait for transmitter to become empty
1079 	 *	and restore UCR1/2
1080 	 */
1081 	while (!(readl(sport->port.membase + USR2) & USR2_TXDC));
1082 
1083 	writel(old_ucr1, sport->port.membase + UCR1);
1084 	writel(old_ucr2, sport->port.membase + UCR2);
1085 }
1086 
1087 /*
1088  * If the port was already initialised (eg, by a boot loader),
1089  * try to determine the current setup.
1090  */
1091 static void __init
1092 imx_console_get_options(struct imx_port *sport, int *baud,
1093 			   int *parity, int *bits)
1094 {
1095 
1096 	if (readl(sport->port.membase + UCR1) & UCR1_UARTEN) {
1097 		/* ok, the port was enabled */
1098 		unsigned int ucr2, ubir,ubmr, uartclk;
1099 		unsigned int baud_raw;
1100 		unsigned int ucfr_rfdiv;
1101 
1102 		ucr2 = readl(sport->port.membase + UCR2);
1103 
1104 		*parity = 'n';
1105 		if (ucr2 & UCR2_PREN) {
1106 			if (ucr2 & UCR2_PROE)
1107 				*parity = 'o';
1108 			else
1109 				*parity = 'e';
1110 		}
1111 
1112 		if (ucr2 & UCR2_WS)
1113 			*bits = 8;
1114 		else
1115 			*bits = 7;
1116 
1117 		ubir = readl(sport->port.membase + UBIR) & 0xffff;
1118 		ubmr = readl(sport->port.membase + UBMR) & 0xffff;
1119 
1120 		ucfr_rfdiv = (readl(sport->port.membase + UFCR) & UFCR_RFDIV) >> 7;
1121 		if (ucfr_rfdiv == 6)
1122 			ucfr_rfdiv = 7;
1123 		else
1124 			ucfr_rfdiv = 6 - ucfr_rfdiv;
1125 
1126 		uartclk = clk_get_rate(sport->clk);
1127 		uartclk /= ucfr_rfdiv;
1128 
1129 		{	/*
1130 			 * The next code provides exact computation of
1131 			 *   baud_raw = round(((uartclk/16) * (ubir + 1)) / (ubmr + 1))
1132 			 * without need of float support or long long division,
1133 			 * which would be required to prevent 32bit arithmetic overflow
1134 			 */
1135 			unsigned int mul = ubir + 1;
1136 			unsigned int div = 16 * (ubmr + 1);
1137 			unsigned int rem = uartclk % div;
1138 
1139 			baud_raw = (uartclk / div) * mul;
1140 			baud_raw += (rem * mul + div / 2) / div;
1141 			*baud = (baud_raw + 50) / 100 * 100;
1142 		}
1143 
1144 		if(*baud != baud_raw)
1145 			printk(KERN_INFO "Serial: Console IMX rounded baud rate from %d to %d\n",
1146 				baud_raw, *baud);
1147 	}
1148 }
1149 
1150 static int __init
1151 imx_console_setup(struct console *co, char *options)
1152 {
1153 	struct imx_port *sport;
1154 	int baud = 9600;
1155 	int bits = 8;
1156 	int parity = 'n';
1157 	int flow = 'n';
1158 
1159 	/*
1160 	 * Check whether an invalid uart number has been specified, and
1161 	 * if so, search for the first available port that does have
1162 	 * console support.
1163 	 */
1164 	if (co->index == -1 || co->index >= ARRAY_SIZE(imx_ports))
1165 		co->index = 0;
1166 	sport = imx_ports[co->index];
1167 	if(sport == NULL)
1168 		return -ENODEV;
1169 
1170 	if (options)
1171 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1172 	else
1173 		imx_console_get_options(sport, &baud, &parity, &bits);
1174 
1175 	imx_setup_ufcr(sport, 0);
1176 
1177 	return uart_set_options(&sport->port, co, baud, parity, bits, flow);
1178 }
1179 
1180 static struct uart_driver imx_reg;
1181 static struct console imx_console = {
1182 	.name		= DEV_NAME,
1183 	.write		= imx_console_write,
1184 	.device		= uart_console_device,
1185 	.setup		= imx_console_setup,
1186 	.flags		= CON_PRINTBUFFER,
1187 	.index		= -1,
1188 	.data		= &imx_reg,
1189 };
1190 
1191 #define IMX_CONSOLE	&imx_console
1192 #else
1193 #define IMX_CONSOLE	NULL
1194 #endif
1195 
1196 static struct uart_driver imx_reg = {
1197 	.owner          = THIS_MODULE,
1198 	.driver_name    = DRIVER_NAME,
1199 	.dev_name       = DEV_NAME,
1200 	.major          = SERIAL_IMX_MAJOR,
1201 	.minor          = MINOR_START,
1202 	.nr             = ARRAY_SIZE(imx_ports),
1203 	.cons           = IMX_CONSOLE,
1204 };
1205 
1206 static int serial_imx_suspend(struct platform_device *dev, pm_message_t state)
1207 {
1208 	struct imx_port *sport = platform_get_drvdata(dev);
1209 
1210 	if (sport)
1211 		uart_suspend_port(&imx_reg, &sport->port);
1212 
1213 	return 0;
1214 }
1215 
1216 static int serial_imx_resume(struct platform_device *dev)
1217 {
1218 	struct imx_port *sport = platform_get_drvdata(dev);
1219 
1220 	if (sport)
1221 		uart_resume_port(&imx_reg, &sport->port);
1222 
1223 	return 0;
1224 }
1225 
1226 static int serial_imx_probe(struct platform_device *pdev)
1227 {
1228 	struct imx_port *sport;
1229 	struct imxuart_platform_data *pdata;
1230 	void __iomem *base;
1231 	int ret = 0;
1232 	struct resource *res;
1233 
1234 	sport = kzalloc(sizeof(*sport), GFP_KERNEL);
1235 	if (!sport)
1236 		return -ENOMEM;
1237 
1238 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1239 	if (!res) {
1240 		ret = -ENODEV;
1241 		goto free;
1242 	}
1243 
1244 	base = ioremap(res->start, PAGE_SIZE);
1245 	if (!base) {
1246 		ret = -ENOMEM;
1247 		goto free;
1248 	}
1249 
1250 	sport->port.dev = &pdev->dev;
1251 	sport->port.mapbase = res->start;
1252 	sport->port.membase = base;
1253 	sport->port.type = PORT_IMX,
1254 	sport->port.iotype = UPIO_MEM;
1255 	sport->port.irq = platform_get_irq(pdev, 0);
1256 	sport->rxirq = platform_get_irq(pdev, 0);
1257 	sport->txirq = platform_get_irq(pdev, 1);
1258 	sport->rtsirq = platform_get_irq(pdev, 2);
1259 	sport->port.fifosize = 32;
1260 	sport->port.ops = &imx_pops;
1261 	sport->port.flags = UPF_BOOT_AUTOCONF;
1262 	sport->port.line = pdev->id;
1263 	init_timer(&sport->timer);
1264 	sport->timer.function = imx_timeout;
1265 	sport->timer.data     = (unsigned long)sport;
1266 
1267 	sport->clk = clk_get(&pdev->dev, "uart");
1268 	if (IS_ERR(sport->clk)) {
1269 		ret = PTR_ERR(sport->clk);
1270 		goto unmap;
1271 	}
1272 	clk_enable(sport->clk);
1273 
1274 	sport->port.uartclk = clk_get_rate(sport->clk);
1275 
1276 	imx_ports[pdev->id] = sport;
1277 
1278 	pdata = pdev->dev.platform_data;
1279 	if (pdata && (pdata->flags & IMXUART_HAVE_RTSCTS))
1280 		sport->have_rtscts = 1;
1281 
1282 #ifdef CONFIG_IRDA
1283 	if (pdata && (pdata->flags & IMXUART_IRDA))
1284 		sport->use_irda = 1;
1285 #endif
1286 
1287 	if (pdata && pdata->init) {
1288 		ret = pdata->init(pdev);
1289 		if (ret)
1290 			goto clkput;
1291 	}
1292 
1293 	ret = uart_add_one_port(&imx_reg, &sport->port);
1294 	if (ret)
1295 		goto deinit;
1296 	platform_set_drvdata(pdev, &sport->port);
1297 
1298 	return 0;
1299 deinit:
1300 	if (pdata && pdata->exit)
1301 		pdata->exit(pdev);
1302 clkput:
1303 	clk_put(sport->clk);
1304 	clk_disable(sport->clk);
1305 unmap:
1306 	iounmap(sport->port.membase);
1307 free:
1308 	kfree(sport);
1309 
1310 	return ret;
1311 }
1312 
1313 static int serial_imx_remove(struct platform_device *pdev)
1314 {
1315 	struct imxuart_platform_data *pdata;
1316 	struct imx_port *sport = platform_get_drvdata(pdev);
1317 
1318 	pdata = pdev->dev.platform_data;
1319 
1320 	platform_set_drvdata(pdev, NULL);
1321 
1322 	if (sport) {
1323 		uart_remove_one_port(&imx_reg, &sport->port);
1324 		clk_put(sport->clk);
1325 	}
1326 
1327 	clk_disable(sport->clk);
1328 
1329 	if (pdata && pdata->exit)
1330 		pdata->exit(pdev);
1331 
1332 	iounmap(sport->port.membase);
1333 	kfree(sport);
1334 
1335 	return 0;
1336 }
1337 
1338 static struct platform_driver serial_imx_driver = {
1339 	.probe		= serial_imx_probe,
1340 	.remove		= serial_imx_remove,
1341 
1342 	.suspend	= serial_imx_suspend,
1343 	.resume		= serial_imx_resume,
1344 	.driver		= {
1345 		.name	= "imx-uart",
1346 		.owner	= THIS_MODULE,
1347 	},
1348 };
1349 
1350 static int __init imx_serial_init(void)
1351 {
1352 	int ret;
1353 
1354 	printk(KERN_INFO "Serial: IMX driver\n");
1355 
1356 	ret = uart_register_driver(&imx_reg);
1357 	if (ret)
1358 		return ret;
1359 
1360 	ret = platform_driver_register(&serial_imx_driver);
1361 	if (ret != 0)
1362 		uart_unregister_driver(&imx_reg);
1363 
1364 	return 0;
1365 }
1366 
1367 static void __exit imx_serial_exit(void)
1368 {
1369 	platform_driver_unregister(&serial_imx_driver);
1370 	uart_unregister_driver(&imx_reg);
1371 }
1372 
1373 module_init(imx_serial_init);
1374 module_exit(imx_serial_exit);
1375 
1376 MODULE_AUTHOR("Sascha Hauer");
1377 MODULE_DESCRIPTION("IMX generic serial port driver");
1378 MODULE_LICENSE("GPL");
1379 MODULE_ALIAS("platform:imx-uart");
1380