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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6/drivers/serial/
1/*
2 *  linux/drivers/serial/imx.c
3 *
4 *  Driver for Motorola IMX serial ports
5 *
6 *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
7 *
8 *  Author: Sascha Hauer <sascha@saschahauer.de>
9 *  Copyright (C) 2004 Pengutronix
10 *
11 *  Copyright (C) 2009 emlix GmbH
12 *  Author: Fabian Godehardt (added IrDA support for iMX)
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
18 *
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22 * GNU General Public License for more details.
23 *
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, write to the Free Software
26 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
27 *
28 * [29-Mar-2005] Mike Lee
29 * Added hardware handshake
30 */
31
32#if defined(CONFIG_SERIAL_IMX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
33#define SUPPORT_SYSRQ
34#endif
35
36#include <linux/module.h>
37#include <linux/ioport.h>
38#include <linux/init.h>
39#include <linux/console.h>
40#include <linux/sysrq.h>
41#include <linux/platform_device.h>
42#include <linux/tty.h>
43#include <linux/tty_flip.h>
44#include <linux/serial_core.h>
45#include <linux/serial.h>
46#include <linux/clk.h>
47#include <linux/delay.h>
48#include <linux/rational.h>
49#include <linux/slab.h>
50
51#include <asm/io.h>
52#include <asm/irq.h>
53#include <mach/hardware.h>
54#include <mach/imx-uart.h>
55
56/* Register definitions */
57#define URXD0 0x0  /* Receiver Register */
58#define URTX0 0x40 /* Transmitter Register */
59#define UCR1  0x80 /* Control Register 1 */
60#define UCR2  0x84 /* Control Register 2 */
61#define UCR3  0x88 /* Control Register 3 */
62#define UCR4  0x8c /* Control Register 4 */
63#define UFCR  0x90 /* FIFO Control Register */
64#define USR1  0x94 /* Status Register 1 */
65#define USR2  0x98 /* Status Register 2 */
66#define UESC  0x9c /* Escape Character Register */
67#define UTIM  0xa0 /* Escape Timer Register */
68#define UBIR  0xa4 /* BRM Incremental Register */
69#define UBMR  0xa8 /* BRM Modulator Register */
70#define UBRC  0xac /* Baud Rate Count Register */
71#define MX2_ONEMS 0xb0 /* One Millisecond register */
72#define UTS (cpu_is_mx1() ? 0xd0 : 0xb4) /* UART Test Register */
73
74/* UART Control Register Bit Fields.*/
75#define  URXD_CHARRDY    (1<<15)
76#define  URXD_ERR        (1<<14)
77#define  URXD_OVRRUN     (1<<13)
78#define  URXD_FRMERR     (1<<12)
79#define  URXD_BRK        (1<<11)
80#define  URXD_PRERR      (1<<10)
81#define  UCR1_ADEN       (1<<15) /* Auto dectect interrupt */
82#define  UCR1_ADBR       (1<<14) /* Auto detect baud rate */
83#define  UCR1_TRDYEN     (1<<13) /* Transmitter ready interrupt enable */
84#define  UCR1_IDEN       (1<<12) /* Idle condition interrupt */
85#define  UCR1_RRDYEN     (1<<9)	 /* Recv ready interrupt enable */
86#define  UCR1_RDMAEN     (1<<8)	 /* Recv ready DMA enable */
87#define  UCR1_IREN       (1<<7)	 /* Infrared interface enable */
88#define  UCR1_TXMPTYEN   (1<<6)	 /* Transimitter empty interrupt enable */
89#define  UCR1_RTSDEN     (1<<5)	 /* RTS delta interrupt enable */
90#define  UCR1_SNDBRK     (1<<4)	 /* Send break */
91#define  UCR1_TDMAEN     (1<<3)	 /* Transmitter ready DMA enable */
92#define  MX1_UCR1_UARTCLKEN  (1<<2)	 /* UART clock enabled, mx1 only */
93#define  UCR1_DOZE       (1<<1)	 /* Doze */
94#define  UCR1_UARTEN     (1<<0)	 /* UART enabled */
95#define  UCR2_ESCI     	 (1<<15) /* Escape seq interrupt enable */
96#define  UCR2_IRTS  	 (1<<14) /* Ignore RTS pin */
97#define  UCR2_CTSC  	 (1<<13) /* CTS pin control */
98#define  UCR2_CTS        (1<<12) /* Clear to send */
99#define  UCR2_ESCEN      (1<<11) /* Escape enable */
100#define  UCR2_PREN       (1<<8)  /* Parity enable */
101#define  UCR2_PROE       (1<<7)  /* Parity odd/even */
102#define  UCR2_STPB       (1<<6)	 /* Stop */
103#define  UCR2_WS         (1<<5)	 /* Word size */
104#define  UCR2_RTSEN      (1<<4)	 /* Request to send interrupt enable */
105#define  UCR2_TXEN       (1<<2)	 /* Transmitter enabled */
106#define  UCR2_RXEN       (1<<1)	 /* Receiver enabled */
107#define  UCR2_SRST 	 (1<<0)	 /* SW reset */
108#define  UCR3_DTREN 	 (1<<13) /* DTR interrupt enable */
109#define  UCR3_PARERREN   (1<<12) /* Parity enable */
110#define  UCR3_FRAERREN   (1<<11) /* Frame error interrupt enable */
111#define  UCR3_DSR        (1<<10) /* Data set ready */
112#define  UCR3_DCD        (1<<9)  /* Data carrier detect */
113#define  UCR3_RI         (1<<8)  /* Ring indicator */
114#define  UCR3_TIMEOUTEN  (1<<7)  /* Timeout interrupt enable */
115#define  UCR3_RXDSEN	 (1<<6)  /* Receive status interrupt enable */
116#define  UCR3_AIRINTEN   (1<<5)  /* Async IR wake interrupt enable */
117#define  UCR3_AWAKEN	 (1<<4)  /* Async wake interrupt enable */
118#define  MX1_UCR3_REF25 	 (1<<3)  /* Ref freq 25 MHz, only on mx1 */
119#define  MX1_UCR3_REF30 	 (1<<2)  /* Ref Freq 30 MHz, only on mx1 */
120#define  MX2_UCR3_RXDMUXSEL	 (1<<2)  /* RXD Muxed Input Select, on mx2/mx3 */
121#define  UCR3_INVT  	 (1<<1)  /* Inverted Infrared transmission */
122#define  UCR3_BPEN  	 (1<<0)  /* Preset registers enable */
123#define  UCR4_CTSTL_SHF  10      /* CTS trigger level shift */
124#define  UCR4_CTSTL_MASK 0x3F    /* CTS trigger is 6 bits wide */
125#define  UCR4_INVR  	 (1<<9)  /* Inverted infrared reception */
126#define  UCR4_ENIRI 	 (1<<8)  /* Serial infrared interrupt enable */
127#define  UCR4_WKEN  	 (1<<7)  /* Wake interrupt enable */
128#define  UCR4_REF16 	 (1<<6)  /* Ref freq 16 MHz */
129#define  UCR4_IRSC  	 (1<<5)  /* IR special case */
130#define  UCR4_TCEN  	 (1<<3)  /* Transmit complete interrupt enable */
131#define  UCR4_BKEN  	 (1<<2)  /* Break condition interrupt enable */
132#define  UCR4_OREN  	 (1<<1)  /* Receiver overrun interrupt enable */
133#define  UCR4_DREN  	 (1<<0)  /* Recv data ready interrupt enable */
134#define  UFCR_RXTL_SHF   0       /* Receiver trigger level shift */
135#define  UFCR_RFDIV      (7<<7)  /* Reference freq divider mask */
136#define  UFCR_RFDIV_REG(x)	(((x) < 7 ? 6 - (x) : 6) << 7)
137#define  UFCR_TXTL_SHF   10      /* Transmitter trigger level shift */
138#define  USR1_PARITYERR  (1<<15) /* Parity error interrupt flag */
139#define  USR1_RTSS  	 (1<<14) /* RTS pin status */
140#define  USR1_TRDY  	 (1<<13) /* Transmitter ready interrupt/dma flag */
141#define  USR1_RTSD  	 (1<<12) /* RTS delta */
142#define  USR1_ESCF  	 (1<<11) /* Escape seq interrupt flag */
143#define  USR1_FRAMERR    (1<<10) /* Frame error interrupt flag */
144#define  USR1_RRDY       (1<<9)	 /* Receiver ready interrupt/dma flag */
145#define  USR1_TIMEOUT    (1<<7)	 /* Receive timeout interrupt status */
146#define  USR1_RXDS  	 (1<<6)	 /* Receiver idle interrupt flag */
147#define  USR1_AIRINT	 (1<<5)	 /* Async IR wake interrupt flag */
148#define  USR1_AWAKE 	 (1<<4)	 /* Aysnc wake interrupt flag */
149#define  USR2_ADET  	 (1<<15) /* Auto baud rate detect complete */
150#define  USR2_TXFE  	 (1<<14) /* Transmit buffer FIFO empty */
151#define  USR2_DTRF  	 (1<<13) /* DTR edge interrupt flag */
152#define  USR2_IDLE  	 (1<<12) /* Idle condition */
153#define  USR2_IRINT 	 (1<<8)	 /* Serial infrared interrupt flag */
154#define  USR2_WAKE  	 (1<<7)	 /* Wake */
155#define  USR2_RTSF  	 (1<<4)	 /* RTS edge interrupt flag */
156#define  USR2_TXDC  	 (1<<3)	 /* Transmitter complete */
157#define  USR2_BRCD  	 (1<<2)	 /* Break condition */
158#define  USR2_ORE        (1<<1)	 /* Overrun error */
159#define  USR2_RDR        (1<<0)	 /* Recv data ready */
160#define  UTS_FRCPERR	 (1<<13) /* Force parity error */
161#define  UTS_LOOP        (1<<12) /* Loop tx and rx */
162#define  UTS_TXEMPTY	 (1<<6)	 /* TxFIFO empty */
163#define  UTS_RXEMPTY	 (1<<5)	 /* RxFIFO empty */
164#define  UTS_TXFULL 	 (1<<4)	 /* TxFIFO full */
165#define  UTS_RXFULL 	 (1<<3)	 /* RxFIFO full */
166#define  UTS_SOFTRST	 (1<<0)	 /* Software reset */
167
168/* We've been assigned a range on the "Low-density serial ports" major */
169#define SERIAL_IMX_MAJOR        207
170#define MINOR_START	        16
171#define DEV_NAME		"ttymxc"
172#define MAX_INTERNAL_IRQ	MXC_INTERNAL_IRQS
173
174/*
175 * This determines how often we check the modem status signals
176 * for any change.  They generally aren't connected to an IRQ
177 * so we have to poll them.  We also check immediately before
178 * filling the TX fifo incase CTS has been dropped.
179 */
180#define MCTRL_TIMEOUT	(250*HZ/1000)
181
182#define DRIVER_NAME "IMX-uart"
183
184#define UART_NR 8
185
186struct imx_port {
187	struct uart_port	port;
188	struct timer_list	timer;
189	unsigned int		old_status;
190	int			txirq,rxirq,rtsirq;
191	unsigned int		have_rtscts:1;
192	unsigned int		use_irda:1;
193	unsigned int		irda_inv_rx:1;
194	unsigned int		irda_inv_tx:1;
195	unsigned short		trcv_delay; /* transceiver delay */
196	struct clk		*clk;
197};
198
199#ifdef CONFIG_IRDA
200#define USE_IRDA(sport)	((sport)->use_irda)
201#else
202#define USE_IRDA(sport)	(0)
203#endif
204
205/*
206 * Handle any change of modem status signal since we were last called.
207 */
208static void imx_mctrl_check(struct imx_port *sport)
209{
210	unsigned int status, changed;
211
212	status = sport->port.ops->get_mctrl(&sport->port);
213	changed = status ^ sport->old_status;
214
215	if (changed == 0)
216		return;
217
218	sport->old_status = status;
219
220	if (changed & TIOCM_RI)
221		sport->port.icount.rng++;
222	if (changed & TIOCM_DSR)
223		sport->port.icount.dsr++;
224	if (changed & TIOCM_CAR)
225		uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
226	if (changed & TIOCM_CTS)
227		uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
228
229	wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
230}
231
232/*
233 * This is our per-port timeout handler, for checking the
234 * modem status signals.
235 */
236static void imx_timeout(unsigned long data)
237{
238	struct imx_port *sport = (struct imx_port *)data;
239	unsigned long flags;
240
241	if (sport->port.state) {
242		spin_lock_irqsave(&sport->port.lock, flags);
243		imx_mctrl_check(sport);
244		spin_unlock_irqrestore(&sport->port.lock, flags);
245
246		mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
247	}
248}
249
250/*
251 * interrupts disabled on entry
252 */
253static void imx_stop_tx(struct uart_port *port)
254{
255	struct imx_port *sport = (struct imx_port *)port;
256	unsigned long temp;
257
258	if (USE_IRDA(sport)) {
259		/* half duplex - wait for end of transmission */
260		int n = 256;
261		while ((--n > 0) &&
262		      !(readl(sport->port.membase + USR2) & USR2_TXDC)) {
263			udelay(5);
264			barrier();
265		}
266		/*
267		 * irda transceiver - wait a bit more to avoid
268		 * cutoff, hardware dependent
269		 */
270		udelay(sport->trcv_delay);
271
272		/*
273		 * half duplex - reactivate receive mode,
274		 * flush receive pipe echo crap
275		 */
276		if (readl(sport->port.membase + USR2) & USR2_TXDC) {
277			temp = readl(sport->port.membase + UCR1);
278			temp &= ~(UCR1_TXMPTYEN | UCR1_TRDYEN);
279			writel(temp, sport->port.membase + UCR1);
280
281			temp = readl(sport->port.membase + UCR4);
282			temp &= ~(UCR4_TCEN);
283			writel(temp, sport->port.membase + UCR4);
284
285			while (readl(sport->port.membase + URXD0) &
286			       URXD_CHARRDY)
287				barrier();
288
289			temp = readl(sport->port.membase + UCR1);
290			temp |= UCR1_RRDYEN;
291			writel(temp, sport->port.membase + UCR1);
292
293			temp = readl(sport->port.membase + UCR4);
294			temp |= UCR4_DREN;
295			writel(temp, sport->port.membase + UCR4);
296		}
297		return;
298	}
299
300	temp = readl(sport->port.membase + UCR1);
301	writel(temp & ~UCR1_TXMPTYEN, sport->port.membase + UCR1);
302}
303
304/*
305 * interrupts disabled on entry
306 */
307static void imx_stop_rx(struct uart_port *port)
308{
309	struct imx_port *sport = (struct imx_port *)port;
310	unsigned long temp;
311
312	temp = readl(sport->port.membase + UCR2);
313	writel(temp &~ UCR2_RXEN, sport->port.membase + UCR2);
314}
315
316/*
317 * Set the modem control timer to fire immediately.
318 */
319static void imx_enable_ms(struct uart_port *port)
320{
321	struct imx_port *sport = (struct imx_port *)port;
322
323	mod_timer(&sport->timer, jiffies);
324}
325
326static inline void imx_transmit_buffer(struct imx_port *sport)
327{
328	struct circ_buf *xmit = &sport->port.state->xmit;
329
330	while (!(readl(sport->port.membase + UTS) & UTS_TXFULL)) {
331		/* send xmit->buf[xmit->tail]
332		 * out the port here */
333		writel(xmit->buf[xmit->tail], sport->port.membase + URTX0);
334		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
335		sport->port.icount.tx++;
336		if (uart_circ_empty(xmit))
337			break;
338	}
339
340	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
341		uart_write_wakeup(&sport->port);
342
343	if (uart_circ_empty(xmit))
344		imx_stop_tx(&sport->port);
345}
346
347/*
348 * interrupts disabled on entry
349 */
350static void imx_start_tx(struct uart_port *port)
351{
352	struct imx_port *sport = (struct imx_port *)port;
353	unsigned long temp;
354
355	if (USE_IRDA(sport)) {
356		/* half duplex in IrDA mode; have to disable receive mode */
357		temp = readl(sport->port.membase + UCR4);
358		temp &= ~(UCR4_DREN);
359		writel(temp, sport->port.membase + UCR4);
360
361		temp = readl(sport->port.membase + UCR1);
362		temp &= ~(UCR1_RRDYEN);
363		writel(temp, sport->port.membase + UCR1);
364	}
365
366	temp = readl(sport->port.membase + UCR1);
367	writel(temp | UCR1_TXMPTYEN, sport->port.membase + UCR1);
368
369	if (USE_IRDA(sport)) {
370		temp = readl(sport->port.membase + UCR1);
371		temp |= UCR1_TRDYEN;
372		writel(temp, sport->port.membase + UCR1);
373
374		temp = readl(sport->port.membase + UCR4);
375		temp |= UCR4_TCEN;
376		writel(temp, sport->port.membase + UCR4);
377	}
378
379	if (readl(sport->port.membase + UTS) & UTS_TXEMPTY)
380		imx_transmit_buffer(sport);
381}
382
383static irqreturn_t imx_rtsint(int irq, void *dev_id)
384{
385	struct imx_port *sport = dev_id;
386	unsigned int val = readl(sport->port.membase + USR1) & USR1_RTSS;
387	unsigned long flags;
388
389	spin_lock_irqsave(&sport->port.lock, flags);
390
391	writel(USR1_RTSD, sport->port.membase + USR1);
392	uart_handle_cts_change(&sport->port, !!val);
393	wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
394
395	spin_unlock_irqrestore(&sport->port.lock, flags);
396	return IRQ_HANDLED;
397}
398
399static irqreturn_t imx_txint(int irq, void *dev_id)
400{
401	struct imx_port *sport = dev_id;
402	struct circ_buf *xmit = &sport->port.state->xmit;
403	unsigned long flags;
404
405	spin_lock_irqsave(&sport->port.lock,flags);
406	if (sport->port.x_char)
407	{
408		/* Send next char */
409		writel(sport->port.x_char, sport->port.membase + URTX0);
410		goto out;
411	}
412
413	if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
414		imx_stop_tx(&sport->port);
415		goto out;
416	}
417
418	imx_transmit_buffer(sport);
419
420	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
421		uart_write_wakeup(&sport->port);
422
423out:
424	spin_unlock_irqrestore(&sport->port.lock,flags);
425	return IRQ_HANDLED;
426}
427
428static irqreturn_t imx_rxint(int irq, void *dev_id)
429{
430	struct imx_port *sport = dev_id;
431	unsigned int rx,flg,ignored = 0;
432	struct tty_struct *tty = sport->port.state->port.tty;
433	unsigned long flags, temp;
434
435	spin_lock_irqsave(&sport->port.lock,flags);
436
437	while (readl(sport->port.membase + USR2) & USR2_RDR) {
438		flg = TTY_NORMAL;
439		sport->port.icount.rx++;
440
441		rx = readl(sport->port.membase + URXD0);
442
443		temp = readl(sport->port.membase + USR2);
444		if (temp & USR2_BRCD) {
445			writel(USR2_BRCD, sport->port.membase + USR2);
446			if (uart_handle_break(&sport->port))
447				continue;
448		}
449
450		if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx))
451			continue;
452
453		if (rx & (URXD_PRERR | URXD_OVRRUN | URXD_FRMERR) ) {
454			if (rx & URXD_PRERR)
455				sport->port.icount.parity++;
456			else if (rx & URXD_FRMERR)
457				sport->port.icount.frame++;
458			if (rx & URXD_OVRRUN)
459				sport->port.icount.overrun++;
460
461			if (rx & sport->port.ignore_status_mask) {
462				if (++ignored > 100)
463					goto out;
464				continue;
465			}
466
467			rx &= sport->port.read_status_mask;
468
469			if (rx & URXD_PRERR)
470				flg = TTY_PARITY;
471			else if (rx & URXD_FRMERR)
472				flg = TTY_FRAME;
473			if (rx & URXD_OVRRUN)
474				flg = TTY_OVERRUN;
475
476#ifdef SUPPORT_SYSRQ
477			sport->port.sysrq = 0;
478#endif
479		}
480
481		tty_insert_flip_char(tty, rx, flg);
482	}
483
484out:
485	spin_unlock_irqrestore(&sport->port.lock,flags);
486	tty_flip_buffer_push(tty);
487	return IRQ_HANDLED;
488}
489
490static irqreturn_t imx_int(int irq, void *dev_id)
491{
492	struct imx_port *sport = dev_id;
493	unsigned int sts;
494
495	sts = readl(sport->port.membase + USR1);
496
497	if (sts & USR1_RRDY)
498		imx_rxint(irq, dev_id);
499
500	if (sts & USR1_TRDY &&
501			readl(sport->port.membase + UCR1) & UCR1_TXMPTYEN)
502		imx_txint(irq, dev_id);
503
504	if (sts & USR1_RTSD)
505		imx_rtsint(irq, dev_id);
506
507	return IRQ_HANDLED;
508}
509
510/*
511 * Return TIOCSER_TEMT when transmitter is not busy.
512 */
513static unsigned int imx_tx_empty(struct uart_port *port)
514{
515	struct imx_port *sport = (struct imx_port *)port;
516
517	return (readl(sport->port.membase + USR2) & USR2_TXDC) ?  TIOCSER_TEMT : 0;
518}
519
520/*
521 * We have a modem side uart, so the meanings of RTS and CTS are inverted.
522 */
523static unsigned int imx_get_mctrl(struct uart_port *port)
524{
525	struct imx_port *sport = (struct imx_port *)port;
526	unsigned int tmp = TIOCM_DSR | TIOCM_CAR;
527
528	if (readl(sport->port.membase + USR1) & USR1_RTSS)
529		tmp |= TIOCM_CTS;
530
531	if (readl(sport->port.membase + UCR2) & UCR2_CTS)
532		tmp |= TIOCM_RTS;
533
534	return tmp;
535}
536
537static void imx_set_mctrl(struct uart_port *port, unsigned int mctrl)
538{
539	struct imx_port *sport = (struct imx_port *)port;
540	unsigned long temp;
541
542	temp = readl(sport->port.membase + UCR2) & ~UCR2_CTS;
543
544	if (mctrl & TIOCM_RTS)
545		temp |= UCR2_CTS;
546
547	writel(temp, sport->port.membase + UCR2);
548}
549
550/*
551 * Interrupts always disabled.
552 */
553static void imx_break_ctl(struct uart_port *port, int break_state)
554{
555	struct imx_port *sport = (struct imx_port *)port;
556	unsigned long flags, temp;
557
558	spin_lock_irqsave(&sport->port.lock, flags);
559
560	temp = readl(sport->port.membase + UCR1) & ~UCR1_SNDBRK;
561
562	if ( break_state != 0 )
563		temp |= UCR1_SNDBRK;
564
565	writel(temp, sport->port.membase + UCR1);
566
567	spin_unlock_irqrestore(&sport->port.lock, flags);
568}
569
570#define TXTL 2 /* reset default */
571#define RXTL 1 /* reset default */
572
573static int imx_setup_ufcr(struct imx_port *sport, unsigned int mode)
574{
575	unsigned int val;
576	unsigned int ufcr_rfdiv;
577
578	/* set receiver / transmitter trigger level.
579	 * RFDIV is set such way to satisfy requested uartclk value
580	 */
581	val = TXTL << 10 | RXTL;
582	ufcr_rfdiv = (clk_get_rate(sport->clk) + sport->port.uartclk / 2)
583			/ sport->port.uartclk;
584
585	if(!ufcr_rfdiv)
586		ufcr_rfdiv = 1;
587
588	val |= UFCR_RFDIV_REG(ufcr_rfdiv);
589
590	writel(val, sport->port.membase + UFCR);
591
592	return 0;
593}
594
595/* half the RX buffer size */
596#define CTSTL 16
597
598static int imx_startup(struct uart_port *port)
599{
600	struct imx_port *sport = (struct imx_port *)port;
601	int retval;
602	unsigned long flags, temp;
603
604	imx_setup_ufcr(sport, 0);
605
606	/* disable the DREN bit (Data Ready interrupt enable) before
607	 * requesting IRQs
608	 */
609	temp = readl(sport->port.membase + UCR4);
610
611	if (USE_IRDA(sport))
612		temp |= UCR4_IRSC;
613
614	/* set the trigger level for CTS */
615	temp &= ~(UCR4_CTSTL_MASK<<  UCR4_CTSTL_SHF);
616	temp |= CTSTL<<  UCR4_CTSTL_SHF;
617
618	writel(temp & ~UCR4_DREN, sport->port.membase + UCR4);
619
620	if (USE_IRDA(sport)) {
621		/* reset fifo's and state machines */
622		int i = 100;
623		temp = readl(sport->port.membase + UCR2);
624		temp &= ~UCR2_SRST;
625		writel(temp, sport->port.membase + UCR2);
626		while (!(readl(sport->port.membase + UCR2) & UCR2_SRST) &&
627		    (--i > 0)) {
628			udelay(1);
629		}
630	}
631
632	/*
633	 * Allocate the IRQ(s) i.MX1 has three interrupts whereas later
634	 * chips only have one interrupt.
635	 */
636	if (sport->txirq > 0) {
637		retval = request_irq(sport->rxirq, imx_rxint, 0,
638				DRIVER_NAME, sport);
639		if (retval)
640			goto error_out1;
641
642		retval = request_irq(sport->txirq, imx_txint, 0,
643				DRIVER_NAME, sport);
644		if (retval)
645			goto error_out2;
646
647		/* do not use RTS IRQ on IrDA */
648		if (!USE_IRDA(sport)) {
649			retval = request_irq(sport->rtsirq, imx_rtsint,
650				     (sport->rtsirq < MAX_INTERNAL_IRQ) ? 0 :
651				       IRQF_TRIGGER_FALLING |
652				       IRQF_TRIGGER_RISING,
653					DRIVER_NAME, sport);
654			if (retval)
655				goto error_out3;
656		}
657	} else {
658		retval = request_irq(sport->port.irq, imx_int, 0,
659				DRIVER_NAME, sport);
660		if (retval) {
661			free_irq(sport->port.irq, sport);
662			goto error_out1;
663		}
664	}
665
666	/*
667	 * Finally, clear and enable interrupts
668	 */
669	writel(USR1_RTSD, sport->port.membase + USR1);
670
671	temp = readl(sport->port.membase + UCR1);
672	temp |= UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN;
673
674	if (USE_IRDA(sport)) {
675		temp |= UCR1_IREN;
676		temp &= ~(UCR1_RTSDEN);
677	}
678
679	writel(temp, sport->port.membase + UCR1);
680
681	temp = readl(sport->port.membase + UCR2);
682	temp |= (UCR2_RXEN | UCR2_TXEN);
683	writel(temp, sport->port.membase + UCR2);
684
685	if (USE_IRDA(sport)) {
686		/* clear RX-FIFO */
687		int i = 64;
688		while ((--i > 0) &&
689			(readl(sport->port.membase + URXD0) & URXD_CHARRDY)) {
690			barrier();
691		}
692	}
693
694	if (!cpu_is_mx1()) {
695		temp = readl(sport->port.membase + UCR3);
696		temp |= MX2_UCR3_RXDMUXSEL;
697		writel(temp, sport->port.membase + UCR3);
698	}
699
700	if (USE_IRDA(sport)) {
701		temp = readl(sport->port.membase + UCR4);
702		if (sport->irda_inv_rx)
703			temp |= UCR4_INVR;
704		else
705			temp &= ~(UCR4_INVR);
706		writel(temp | UCR4_DREN, sport->port.membase + UCR4);
707
708		temp = readl(sport->port.membase + UCR3);
709		if (sport->irda_inv_tx)
710			temp |= UCR3_INVT;
711		else
712			temp &= ~(UCR3_INVT);
713		writel(temp, sport->port.membase + UCR3);
714	}
715
716	/*
717	 * Enable modem status interrupts
718	 */
719	spin_lock_irqsave(&sport->port.lock,flags);
720	imx_enable_ms(&sport->port);
721	spin_unlock_irqrestore(&sport->port.lock,flags);
722
723	if (USE_IRDA(sport)) {
724		struct imxuart_platform_data *pdata;
725		pdata = sport->port.dev->platform_data;
726		sport->irda_inv_rx = pdata->irda_inv_rx;
727		sport->irda_inv_tx = pdata->irda_inv_tx;
728		sport->trcv_delay = pdata->transceiver_delay;
729		if (pdata->irda_enable)
730			pdata->irda_enable(1);
731	}
732
733	return 0;
734
735error_out3:
736	if (sport->txirq)
737		free_irq(sport->txirq, sport);
738error_out2:
739	if (sport->rxirq)
740		free_irq(sport->rxirq, sport);
741error_out1:
742	return retval;
743}
744
745static void imx_shutdown(struct uart_port *port)
746{
747	struct imx_port *sport = (struct imx_port *)port;
748	unsigned long temp;
749
750	temp = readl(sport->port.membase + UCR2);
751	temp &= ~(UCR2_TXEN);
752	writel(temp, sport->port.membase + UCR2);
753
754	if (USE_IRDA(sport)) {
755		struct imxuart_platform_data *pdata;
756		pdata = sport->port.dev->platform_data;
757		if (pdata->irda_enable)
758			pdata->irda_enable(0);
759	}
760
761	/*
762	 * Stop our timer.
763	 */
764	del_timer_sync(&sport->timer);
765
766	/*
767	 * Free the interrupts
768	 */
769	if (sport->txirq > 0) {
770		if (!USE_IRDA(sport))
771			free_irq(sport->rtsirq, sport);
772		free_irq(sport->txirq, sport);
773		free_irq(sport->rxirq, sport);
774	} else
775		free_irq(sport->port.irq, sport);
776
777	/*
778	 * Disable all interrupts, port and break condition.
779	 */
780
781	temp = readl(sport->port.membase + UCR1);
782	temp &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN);
783	if (USE_IRDA(sport))
784		temp &= ~(UCR1_IREN);
785
786	writel(temp, sport->port.membase + UCR1);
787}
788
789static void
790imx_set_termios(struct uart_port *port, struct ktermios *termios,
791		   struct ktermios *old)
792{
793	struct imx_port *sport = (struct imx_port *)port;
794	unsigned long flags;
795	unsigned int ucr2, old_ucr1, old_txrxen, baud, quot;
796	unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
797	unsigned int div, ufcr;
798	unsigned long num, denom;
799	uint64_t tdiv64;
800
801	/*
802	 * If we don't support modem control lines, don't allow
803	 * these to be set.
804	 */
805	if (0) {
806		termios->c_cflag &= ~(HUPCL | CRTSCTS | CMSPAR);
807		termios->c_cflag |= CLOCAL;
808	}
809
810	/*
811	 * We only support CS7 and CS8.
812	 */
813	while ((termios->c_cflag & CSIZE) != CS7 &&
814	       (termios->c_cflag & CSIZE) != CS8) {
815		termios->c_cflag &= ~CSIZE;
816		termios->c_cflag |= old_csize;
817		old_csize = CS8;
818	}
819
820	if ((termios->c_cflag & CSIZE) == CS8)
821		ucr2 = UCR2_WS | UCR2_SRST | UCR2_IRTS;
822	else
823		ucr2 = UCR2_SRST | UCR2_IRTS;
824
825	if (termios->c_cflag & CRTSCTS) {
826		if( sport->have_rtscts ) {
827			ucr2 &= ~UCR2_IRTS;
828			ucr2 |= UCR2_CTSC;
829		} else {
830			termios->c_cflag &= ~CRTSCTS;
831		}
832	}
833
834	if (termios->c_cflag & CSTOPB)
835		ucr2 |= UCR2_STPB;
836	if (termios->c_cflag & PARENB) {
837		ucr2 |= UCR2_PREN;
838		if (termios->c_cflag & PARODD)
839			ucr2 |= UCR2_PROE;
840	}
841
842	/*
843	 * Ask the core to calculate the divisor for us.
844	 */
845	baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
846	quot = uart_get_divisor(port, baud);
847
848	spin_lock_irqsave(&sport->port.lock, flags);
849
850	sport->port.read_status_mask = 0;
851	if (termios->c_iflag & INPCK)
852		sport->port.read_status_mask |= (URXD_FRMERR | URXD_PRERR);
853	if (termios->c_iflag & (BRKINT | PARMRK))
854		sport->port.read_status_mask |= URXD_BRK;
855
856	/*
857	 * Characters to ignore
858	 */
859	sport->port.ignore_status_mask = 0;
860	if (termios->c_iflag & IGNPAR)
861		sport->port.ignore_status_mask |= URXD_PRERR;
862	if (termios->c_iflag & IGNBRK) {
863		sport->port.ignore_status_mask |= URXD_BRK;
864		/*
865		 * If we're ignoring parity and break indicators,
866		 * ignore overruns too (for real raw support).
867		 */
868		if (termios->c_iflag & IGNPAR)
869			sport->port.ignore_status_mask |= URXD_OVRRUN;
870	}
871
872	del_timer_sync(&sport->timer);
873
874	/*
875	 * Update the per-port timeout.
876	 */
877	uart_update_timeout(port, termios->c_cflag, baud);
878
879	/*
880	 * disable interrupts and drain transmitter
881	 */
882	old_ucr1 = readl(sport->port.membase + UCR1);
883	writel(old_ucr1 & ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN),
884			sport->port.membase + UCR1);
885
886	while ( !(readl(sport->port.membase + USR2) & USR2_TXDC))
887		barrier();
888
889	/* then, disable everything */
890	old_txrxen = readl(sport->port.membase + UCR2);
891	writel(old_txrxen & ~( UCR2_TXEN | UCR2_RXEN),
892			sport->port.membase + UCR2);
893	old_txrxen &= (UCR2_TXEN | UCR2_RXEN);
894
895	if (USE_IRDA(sport)) {
896		/*
897		 * use maximum available submodule frequency to
898		 * avoid missing short pulses due to low sampling rate
899		 */
900		div = 1;
901	} else {
902		div = sport->port.uartclk / (baud * 16);
903		if (div > 7)
904			div = 7;
905		if (!div)
906			div = 1;
907	}
908
909	rational_best_approximation(16 * div * baud, sport->port.uartclk,
910		1 << 16, 1 << 16, &num, &denom);
911
912	tdiv64 = sport->port.uartclk;
913	tdiv64 *= num;
914	do_div(tdiv64, denom * 16 * div);
915	tty_termios_encode_baud_rate(termios,
916				(speed_t)tdiv64, (speed_t)tdiv64);
917
918	num -= 1;
919	denom -= 1;
920
921	ufcr = readl(sport->port.membase + UFCR);
922	ufcr = (ufcr & (~UFCR_RFDIV)) | UFCR_RFDIV_REG(div);
923	writel(ufcr, sport->port.membase + UFCR);
924
925	writel(num, sport->port.membase + UBIR);
926	writel(denom, sport->port.membase + UBMR);
927
928	if (!cpu_is_mx1())
929		writel(sport->port.uartclk / div / 1000,
930				sport->port.membase + MX2_ONEMS);
931
932	writel(old_ucr1, sport->port.membase + UCR1);
933
934	/* set the parity, stop bits and data size */
935	writel(ucr2 | old_txrxen, sport->port.membase + UCR2);
936
937	if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
938		imx_enable_ms(&sport->port);
939
940	spin_unlock_irqrestore(&sport->port.lock, flags);
941}
942
943static const char *imx_type(struct uart_port *port)
944{
945	struct imx_port *sport = (struct imx_port *)port;
946
947	return sport->port.type == PORT_IMX ? "IMX" : NULL;
948}
949
950/*
951 * Release the memory region(s) being used by 'port'.
952 */
953static void imx_release_port(struct uart_port *port)
954{
955	struct platform_device *pdev = to_platform_device(port->dev);
956	struct resource *mmres;
957
958	mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
959	release_mem_region(mmres->start, mmres->end - mmres->start + 1);
960}
961
962/*
963 * Request the memory region(s) being used by 'port'.
964 */
965static int imx_request_port(struct uart_port *port)
966{
967	struct platform_device *pdev = to_platform_device(port->dev);
968	struct resource *mmres;
969	void *ret;
970
971	mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
972	if (!mmres)
973		return -ENODEV;
974
975	ret = request_mem_region(mmres->start, mmres->end - mmres->start + 1,
976			"imx-uart");
977
978	return  ret ? 0 : -EBUSY;
979}
980
981/*
982 * Configure/autoconfigure the port.
983 */
984static void imx_config_port(struct uart_port *port, int flags)
985{
986	struct imx_port *sport = (struct imx_port *)port;
987
988	if (flags & UART_CONFIG_TYPE &&
989	    imx_request_port(&sport->port) == 0)
990		sport->port.type = PORT_IMX;
991}
992
993/*
994 * Verify the new serial_struct (for TIOCSSERIAL).
995 * The only change we allow are to the flags and type, and
996 * even then only between PORT_IMX and PORT_UNKNOWN
997 */
998static int
999imx_verify_port(struct uart_port *port, struct serial_struct *ser)
1000{
1001	struct imx_port *sport = (struct imx_port *)port;
1002	int ret = 0;
1003
1004	if (ser->type != PORT_UNKNOWN && ser->type != PORT_IMX)
1005		ret = -EINVAL;
1006	if (sport->port.irq != ser->irq)
1007		ret = -EINVAL;
1008	if (ser->io_type != UPIO_MEM)
1009		ret = -EINVAL;
1010	if (sport->port.uartclk / 16 != ser->baud_base)
1011		ret = -EINVAL;
1012	if ((void *)sport->port.mapbase != ser->iomem_base)
1013		ret = -EINVAL;
1014	if (sport->port.iobase != ser->port)
1015		ret = -EINVAL;
1016	if (ser->hub6 != 0)
1017		ret = -EINVAL;
1018	return ret;
1019}
1020
1021static struct uart_ops imx_pops = {
1022	.tx_empty	= imx_tx_empty,
1023	.set_mctrl	= imx_set_mctrl,
1024	.get_mctrl	= imx_get_mctrl,
1025	.stop_tx	= imx_stop_tx,
1026	.start_tx	= imx_start_tx,
1027	.stop_rx	= imx_stop_rx,
1028	.enable_ms	= imx_enable_ms,
1029	.break_ctl	= imx_break_ctl,
1030	.startup	= imx_startup,
1031	.shutdown	= imx_shutdown,
1032	.set_termios	= imx_set_termios,
1033	.type		= imx_type,
1034	.release_port	= imx_release_port,
1035	.request_port	= imx_request_port,
1036	.config_port	= imx_config_port,
1037	.verify_port	= imx_verify_port,
1038};
1039
1040static struct imx_port *imx_ports[UART_NR];
1041
1042#ifdef CONFIG_SERIAL_IMX_CONSOLE
1043static void imx_console_putchar(struct uart_port *port, int ch)
1044{
1045	struct imx_port *sport = (struct imx_port *)port;
1046
1047	while (readl(sport->port.membase + UTS) & UTS_TXFULL)
1048		barrier();
1049
1050	writel(ch, sport->port.membase + URTX0);
1051}
1052
1053/*
1054 * Interrupts are disabled on entering
1055 */
1056static void
1057imx_console_write(struct console *co, const char *s, unsigned int count)
1058{
1059	struct imx_port *sport = imx_ports[co->index];
1060	unsigned int old_ucr1, old_ucr2, ucr1;
1061
1062	/*
1063	 *	First, save UCR1/2 and then disable interrupts
1064	 */
1065	ucr1 = old_ucr1 = readl(sport->port.membase + UCR1);
1066	old_ucr2 = readl(sport->port.membase + UCR2);
1067
1068	if (cpu_is_mx1())
1069		ucr1 |= MX1_UCR1_UARTCLKEN;
1070	ucr1 |= UCR1_UARTEN;
1071	ucr1 &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN);
1072
1073	writel(ucr1, sport->port.membase + UCR1);
1074
1075	writel(old_ucr2 | UCR2_TXEN, sport->port.membase + UCR2);
1076
1077	uart_console_write(&sport->port, s, count, imx_console_putchar);
1078
1079	/*
1080	 *	Finally, wait for transmitter to become empty
1081	 *	and restore UCR1/2
1082	 */
1083	while (!(readl(sport->port.membase + USR2) & USR2_TXDC));
1084
1085	writel(old_ucr1, sport->port.membase + UCR1);
1086	writel(old_ucr2, sport->port.membase + UCR2);
1087}
1088
1089/*
1090 * If the port was already initialised (eg, by a boot loader),
1091 * try to determine the current setup.
1092 */
1093static void __init
1094imx_console_get_options(struct imx_port *sport, int *baud,
1095			   int *parity, int *bits)
1096{
1097
1098	if (readl(sport->port.membase + UCR1) & UCR1_UARTEN) {
1099		/* ok, the port was enabled */
1100		unsigned int ucr2, ubir,ubmr, uartclk;
1101		unsigned int baud_raw;
1102		unsigned int ucfr_rfdiv;
1103
1104		ucr2 = readl(sport->port.membase + UCR2);
1105
1106		*parity = 'n';
1107		if (ucr2 & UCR2_PREN) {
1108			if (ucr2 & UCR2_PROE)
1109				*parity = 'o';
1110			else
1111				*parity = 'e';
1112		}
1113
1114		if (ucr2 & UCR2_WS)
1115			*bits = 8;
1116		else
1117			*bits = 7;
1118
1119		ubir = readl(sport->port.membase + UBIR) & 0xffff;
1120		ubmr = readl(sport->port.membase + UBMR) & 0xffff;
1121
1122		ucfr_rfdiv = (readl(sport->port.membase + UFCR) & UFCR_RFDIV) >> 7;
1123		if (ucfr_rfdiv == 6)
1124			ucfr_rfdiv = 7;
1125		else
1126			ucfr_rfdiv = 6 - ucfr_rfdiv;
1127
1128		uartclk = clk_get_rate(sport->clk);
1129		uartclk /= ucfr_rfdiv;
1130
1131		{	/*
1132			 * The next code provides exact computation of
1133			 *   baud_raw = round(((uartclk/16) * (ubir + 1)) / (ubmr + 1))
1134			 * without need of float support or long long division,
1135			 * which would be required to prevent 32bit arithmetic overflow
1136			 */
1137			unsigned int mul = ubir + 1;
1138			unsigned int div = 16 * (ubmr + 1);
1139			unsigned int rem = uartclk % div;
1140
1141			baud_raw = (uartclk / div) * mul;
1142			baud_raw += (rem * mul + div / 2) / div;
1143			*baud = (baud_raw + 50) / 100 * 100;
1144		}
1145
1146		if(*baud != baud_raw)
1147			printk(KERN_INFO "Serial: Console IMX rounded baud rate from %d to %d\n",
1148				baud_raw, *baud);
1149	}
1150}
1151
1152static int __init
1153imx_console_setup(struct console *co, char *options)
1154{
1155	struct imx_port *sport;
1156	int baud = 9600;
1157	int bits = 8;
1158	int parity = 'n';
1159	int flow = 'n';
1160
1161	/*
1162	 * Check whether an invalid uart number has been specified, and
1163	 * if so, search for the first available port that does have
1164	 * console support.
1165	 */
1166	if (co->index == -1 || co->index >= ARRAY_SIZE(imx_ports))
1167		co->index = 0;
1168	sport = imx_ports[co->index];
1169	if(sport == NULL)
1170		return -ENODEV;
1171
1172	if (options)
1173		uart_parse_options(options, &baud, &parity, &bits, &flow);
1174	else
1175		imx_console_get_options(sport, &baud, &parity, &bits);
1176
1177	imx_setup_ufcr(sport, 0);
1178
1179	return uart_set_options(&sport->port, co, baud, parity, bits, flow);
1180}
1181
1182static struct uart_driver imx_reg;
1183static struct console imx_console = {
1184	.name		= DEV_NAME,
1185	.write		= imx_console_write,
1186	.device		= uart_console_device,
1187	.setup		= imx_console_setup,
1188	.flags		= CON_PRINTBUFFER,
1189	.index		= -1,
1190	.data		= &imx_reg,
1191};
1192
1193#define IMX_CONSOLE	&imx_console
1194#else
1195#define IMX_CONSOLE	NULL
1196#endif
1197
1198static struct uart_driver imx_reg = {
1199	.owner          = THIS_MODULE,
1200	.driver_name    = DRIVER_NAME,
1201	.dev_name       = DEV_NAME,
1202	.major          = SERIAL_IMX_MAJOR,
1203	.minor          = MINOR_START,
1204	.nr             = ARRAY_SIZE(imx_ports),
1205	.cons           = IMX_CONSOLE,
1206};
1207
1208static int serial_imx_suspend(struct platform_device *dev, pm_message_t state)
1209{
1210	struct imx_port *sport = platform_get_drvdata(dev);
1211
1212	if (sport)
1213		uart_suspend_port(&imx_reg, &sport->port);
1214
1215	return 0;
1216}
1217
1218static int serial_imx_resume(struct platform_device *dev)
1219{
1220	struct imx_port *sport = platform_get_drvdata(dev);
1221
1222	if (sport)
1223		uart_resume_port(&imx_reg, &sport->port);
1224
1225	return 0;
1226}
1227
1228static int serial_imx_probe(struct platform_device *pdev)
1229{
1230	struct imx_port *sport;
1231	struct imxuart_platform_data *pdata;
1232	void __iomem *base;
1233	int ret = 0;
1234	struct resource *res;
1235
1236	sport = kzalloc(sizeof(*sport), GFP_KERNEL);
1237	if (!sport)
1238		return -ENOMEM;
1239
1240	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1241	if (!res) {
1242		ret = -ENODEV;
1243		goto free;
1244	}
1245
1246	base = ioremap(res->start, PAGE_SIZE);
1247	if (!base) {
1248		ret = -ENOMEM;
1249		goto free;
1250	}
1251
1252	sport->port.dev = &pdev->dev;
1253	sport->port.mapbase = res->start;
1254	sport->port.membase = base;
1255	sport->port.type = PORT_IMX,
1256	sport->port.iotype = UPIO_MEM;
1257	sport->port.irq = platform_get_irq(pdev, 0);
1258	sport->rxirq = platform_get_irq(pdev, 0);
1259	sport->txirq = platform_get_irq(pdev, 1);
1260	sport->rtsirq = platform_get_irq(pdev, 2);
1261	sport->port.fifosize = 32;
1262	sport->port.ops = &imx_pops;
1263	sport->port.flags = UPF_BOOT_AUTOCONF;
1264	sport->port.line = pdev->id;
1265	init_timer(&sport->timer);
1266	sport->timer.function = imx_timeout;
1267	sport->timer.data     = (unsigned long)sport;
1268
1269	sport->clk = clk_get(&pdev->dev, "uart");
1270	if (IS_ERR(sport->clk)) {
1271		ret = PTR_ERR(sport->clk);
1272		goto unmap;
1273	}
1274	clk_enable(sport->clk);
1275
1276	sport->port.uartclk = clk_get_rate(sport->clk);
1277
1278	imx_ports[pdev->id] = sport;
1279
1280	pdata = pdev->dev.platform_data;
1281	if (pdata && (pdata->flags & IMXUART_HAVE_RTSCTS))
1282		sport->have_rtscts = 1;
1283
1284#ifdef CONFIG_IRDA
1285	if (pdata && (pdata->flags & IMXUART_IRDA))
1286		sport->use_irda = 1;
1287#endif
1288
1289	if (pdata && pdata->init) {
1290		ret = pdata->init(pdev);
1291		if (ret)
1292			goto clkput;
1293	}
1294
1295	ret = uart_add_one_port(&imx_reg, &sport->port);
1296	if (ret)
1297		goto deinit;
1298	platform_set_drvdata(pdev, &sport->port);
1299
1300	return 0;
1301deinit:
1302	if (pdata && pdata->exit)
1303		pdata->exit(pdev);
1304clkput:
1305	clk_put(sport->clk);
1306	clk_disable(sport->clk);
1307unmap:
1308	iounmap(sport->port.membase);
1309free:
1310	kfree(sport);
1311
1312	return ret;
1313}
1314
1315static int serial_imx_remove(struct platform_device *pdev)
1316{
1317	struct imxuart_platform_data *pdata;
1318	struct imx_port *sport = platform_get_drvdata(pdev);
1319
1320	pdata = pdev->dev.platform_data;
1321
1322	platform_set_drvdata(pdev, NULL);
1323
1324	if (sport) {
1325		uart_remove_one_port(&imx_reg, &sport->port);
1326		clk_put(sport->clk);
1327	}
1328
1329	clk_disable(sport->clk);
1330
1331	if (pdata && pdata->exit)
1332		pdata->exit(pdev);
1333
1334	iounmap(sport->port.membase);
1335	kfree(sport);
1336
1337	return 0;
1338}
1339
1340static struct platform_driver serial_imx_driver = {
1341	.probe		= serial_imx_probe,
1342	.remove		= serial_imx_remove,
1343
1344	.suspend	= serial_imx_suspend,
1345	.resume		= serial_imx_resume,
1346	.driver		= {
1347		.name	= "imx-uart",
1348		.owner	= THIS_MODULE,
1349	},
1350};
1351
1352static int __init imx_serial_init(void)
1353{
1354	int ret;
1355
1356	printk(KERN_INFO "Serial: IMX driver\n");
1357
1358	ret = uart_register_driver(&imx_reg);
1359	if (ret)
1360		return ret;
1361
1362	ret = platform_driver_register(&serial_imx_driver);
1363	if (ret != 0)
1364		uart_unregister_driver(&imx_reg);
1365
1366	return 0;
1367}
1368
1369static void __exit imx_serial_exit(void)
1370{
1371	platform_driver_unregister(&serial_imx_driver);
1372	uart_unregister_driver(&imx_reg);
1373}
1374
1375module_init(imx_serial_init);
1376module_exit(imx_serial_exit);
1377
1378MODULE_AUTHOR("Sascha Hauer");
1379MODULE_DESCRIPTION("IMX generic serial port driver");
1380MODULE_LICENSE("GPL");
1381MODULE_ALIAS("platform:imx-uart");
1382