2 * linux/drivers/serial/imx.c
4 * Driver for Motorola IMX serial ports
6 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
8 * Author: Sascha Hauer <sascha@saschahauer.de>
9 * Copyright (C) 2004 Pengutronix
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 * [29-Mar-2005] Mike Lee
26 * Added hardware handshake
28 #include <linux/config.h>
30 #if defined(CONFIG_SERIAL_IMX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
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>
47 #include <asm/hardware.h>
49 /* We've been assigned a range on the "Low-density serial ports" major */
50 #define SERIAL_IMX_MAJOR 204
51 #define MINOR_START 41
55 #define IMX_ISR_PASS_LIMIT 256
58 * This is the size of our serial port register set.
60 #define UART_PORT_SIZE 0x100
63 * This determines how often we check the modem status signals
64 * for any change. They generally aren't connected to an IRQ
65 * so we have to poll them. We also check immediately before
66 * filling the TX fifo incase CTS has been dropped.
68 #define MCTRL_TIMEOUT (250*HZ/1000)
70 #define DRIVER_NAME "IMX-uart"
73 struct uart_port port
;
74 struct timer_list timer
;
75 unsigned int old_status
;
76 int txirq
,rxirq
,rtsirq
;
80 * Handle any change of modem status signal since we were last called.
82 static void imx_mctrl_check(struct imx_port
*sport
)
84 unsigned int status
, changed
;
86 status
= sport
->port
.ops
->get_mctrl(&sport
->port
);
87 changed
= status
^ sport
->old_status
;
92 sport
->old_status
= status
;
94 if (changed
& TIOCM_RI
)
95 sport
->port
.icount
.rng
++;
96 if (changed
& TIOCM_DSR
)
97 sport
->port
.icount
.dsr
++;
98 if (changed
& TIOCM_CAR
)
99 uart_handle_dcd_change(&sport
->port
, status
& TIOCM_CAR
);
100 if (changed
& TIOCM_CTS
)
101 uart_handle_cts_change(&sport
->port
, status
& TIOCM_CTS
);
103 wake_up_interruptible(&sport
->port
.info
->delta_msr_wait
);
107 * This is our per-port timeout handler, for checking the
108 * modem status signals.
110 static void imx_timeout(unsigned long data
)
112 struct imx_port
*sport
= (struct imx_port
*)data
;
115 if (sport
->port
.info
) {
116 spin_lock_irqsave(&sport
->port
.lock
, flags
);
117 imx_mctrl_check(sport
);
118 spin_unlock_irqrestore(&sport
->port
.lock
, flags
);
120 mod_timer(&sport
->timer
, jiffies
+ MCTRL_TIMEOUT
);
125 * interrupts disabled on entry
127 static void imx_stop_tx(struct uart_port
*port
)
129 struct imx_port
*sport
= (struct imx_port
*)port
;
130 UCR1((u32
)sport
->port
.membase
) &= ~UCR1_TXMPTYEN
;
134 * interrupts disabled on entry
136 static void imx_stop_rx(struct uart_port
*port
)
138 struct imx_port
*sport
= (struct imx_port
*)port
;
139 UCR2((u32
)sport
->port
.membase
) &= ~UCR2_RXEN
;
143 * Set the modem control timer to fire immediately.
145 static void imx_enable_ms(struct uart_port
*port
)
147 struct imx_port
*sport
= (struct imx_port
*)port
;
149 mod_timer(&sport
->timer
, jiffies
);
152 static inline void imx_transmit_buffer(struct imx_port
*sport
)
154 struct circ_buf
*xmit
= &sport
->port
.info
->xmit
;
157 /* send xmit->buf[xmit->tail]
158 * out the port here */
159 URTX0((u32
)sport
->port
.membase
) = xmit
->buf
[xmit
->tail
];
160 xmit
->tail
= (xmit
->tail
+ 1) &
161 (UART_XMIT_SIZE
- 1);
162 sport
->port
.icount
.tx
++;
163 if (uart_circ_empty(xmit
))
165 } while (!(UTS((u32
)sport
->port
.membase
) & UTS_TXFULL
));
167 if (uart_circ_empty(xmit
))
168 imx_stop_tx(&sport
->port
);
172 * interrupts disabled on entry
174 static void imx_start_tx(struct uart_port
*port
)
176 struct imx_port
*sport
= (struct imx_port
*)port
;
178 UCR1((u32
)sport
->port
.membase
) |= UCR1_TXMPTYEN
;
180 if(UTS((u32
)sport
->port
.membase
) & UTS_TXEMPTY
)
181 imx_transmit_buffer(sport
);
184 static irqreturn_t
imx_rtsint(int irq
, void *dev_id
, struct pt_regs
*regs
)
186 struct imx_port
*sport
= (struct imx_port
*)dev_id
;
187 unsigned int val
= USR1((u32
)sport
->port
.membase
)&USR1_RTSS
;
190 spin_lock_irqsave(&sport
->port
.lock
, flags
);
192 USR1((u32
)sport
->port
.membase
) = USR1_RTSD
;
193 uart_handle_cts_change(&sport
->port
, !!val
);
194 wake_up_interruptible(&sport
->port
.info
->delta_msr_wait
);
196 spin_unlock_irqrestore(&sport
->port
.lock
, flags
);
200 static irqreturn_t
imx_txint(int irq
, void *dev_id
, struct pt_regs
*regs
)
202 struct imx_port
*sport
= (struct imx_port
*)dev_id
;
203 struct circ_buf
*xmit
= &sport
->port
.info
->xmit
;
206 spin_lock_irqsave(&sport
->port
.lock
,flags
);
207 if (sport
->port
.x_char
)
210 URTX0((u32
)sport
->port
.membase
) = sport
->port
.x_char
;
214 if (uart_circ_empty(xmit
) || uart_tx_stopped(&sport
->port
)) {
215 imx_stop_tx(&sport
->port
);
219 imx_transmit_buffer(sport
);
221 if (uart_circ_chars_pending(xmit
) < WAKEUP_CHARS
)
222 uart_write_wakeup(&sport
->port
);
225 spin_unlock_irqrestore(&sport
->port
.lock
,flags
);
229 static irqreturn_t
imx_rxint(int irq
, void *dev_id
, struct pt_regs
*regs
)
231 struct imx_port
*sport
= dev_id
;
232 unsigned int rx
,flg
,ignored
= 0;
233 struct tty_struct
*tty
= sport
->port
.info
->tty
;
236 rx
= URXD0((u32
)sport
->port
.membase
);
237 spin_lock_irqsave(&sport
->port
.lock
,flags
);
241 sport
->port
.icount
.rx
++;
243 if( USR2((u32
)sport
->port
.membase
) & USR2_BRCD
) {
244 USR2((u32
)sport
->port
.membase
) |= USR2_BRCD
;
245 if(uart_handle_break(&sport
->port
))
249 if (uart_handle_sysrq_char
250 (&sport
->port
, (unsigned char)rx
, regs
))
253 if( rx
& (URXD_PRERR
| URXD_OVRRUN
| URXD_FRMERR
) )
257 tty_insert_flip_char(tty
, rx
, flg
);
259 if (tty
->flip
.count
>= TTY_FLIPBUF_SIZE
)
263 rx
= URXD0((u32
)sport
->port
.membase
);
264 } while(rx
& URXD_CHARRDY
);
267 spin_unlock_irqrestore(&sport
->port
.lock
,flags
);
268 tty_flip_buffer_push(tty
);
273 sport
->port
.icount
.parity
++;
274 else if (rx
& URXD_FRMERR
)
275 sport
->port
.icount
.frame
++;
276 if (rx
& URXD_OVRRUN
)
277 sport
->port
.icount
.overrun
++;
279 if (rx
& sport
->port
.ignore_status_mask
) {
285 rx
&= sport
->port
.read_status_mask
;
289 else if (rx
& URXD_FRMERR
)
291 if (rx
& URXD_OVRRUN
)
295 sport
->port
.sysrq
= 0;
301 * Return TIOCSER_TEMT when transmitter is not busy.
303 static unsigned int imx_tx_empty(struct uart_port
*port
)
305 struct imx_port
*sport
= (struct imx_port
*)port
;
307 return USR2((u32
)sport
->port
.membase
) & USR2_TXDC
? TIOCSER_TEMT
: 0;
311 * We have a modem side uart, so the meanings of RTS and CTS are inverted.
313 static unsigned int imx_get_mctrl(struct uart_port
*port
)
315 struct imx_port
*sport
= (struct imx_port
*)port
;
316 unsigned int tmp
= TIOCM_DSR
| TIOCM_CAR
;
318 if (USR1((u32
)sport
->port
.membase
) & USR1_RTSS
)
321 if (UCR2((u32
)sport
->port
.membase
) & UCR2_CTS
)
327 static void imx_set_mctrl(struct uart_port
*port
, unsigned int mctrl
)
329 struct imx_port
*sport
= (struct imx_port
*)port
;
331 if (mctrl
& TIOCM_RTS
)
332 UCR2((u32
)sport
->port
.membase
) |= UCR2_CTS
;
334 UCR2((u32
)sport
->port
.membase
) &= ~UCR2_CTS
;
338 * Interrupts always disabled.
340 static void imx_break_ctl(struct uart_port
*port
, int break_state
)
342 struct imx_port
*sport
= (struct imx_port
*)port
;
345 spin_lock_irqsave(&sport
->port
.lock
, flags
);
347 if ( break_state
!= 0 )
348 UCR1((u32
)sport
->port
.membase
) |= UCR1_SNDBRK
;
350 UCR1((u32
)sport
->port
.membase
) &= ~UCR1_SNDBRK
;
352 spin_unlock_irqrestore(&sport
->port
.lock
, flags
);
355 #define TXTL 2 /* reset default */
356 #define RXTL 1 /* reset default */
358 static int imx_setup_ufcr(struct imx_port
*sport
, unsigned int mode
)
361 unsigned int ufcr_rfdiv
;
363 /* set receiver / transmitter trigger level.
364 * RFDIV is set such way to satisfy requested uartclk value
366 val
= TXTL
<<10 | RXTL
;
367 ufcr_rfdiv
= (imx_get_perclk1() + sport
->port
.uartclk
/ 2) / sport
->port
.uartclk
;
375 ufcr_rfdiv
= 6 - ufcr_rfdiv
;
377 val
|= UFCR_RFDIV
& (ufcr_rfdiv
<< 7);
379 UFCR((u32
)sport
->port
.membase
) = val
;
384 static int imx_startup(struct uart_port
*port
)
386 struct imx_port
*sport
= (struct imx_port
*)port
;
390 imx_setup_ufcr(sport
, 0);
392 /* disable the DREN bit (Data Ready interrupt enable) before
395 UCR4((u32
)sport
->port
.membase
) &= ~UCR4_DREN
;
400 retval
= request_irq(sport
->rxirq
, imx_rxint
, 0,
402 if (retval
) goto error_out1
;
404 retval
= request_irq(sport
->txirq
, imx_txint
, 0,
406 if (retval
) goto error_out2
;
408 retval
= request_irq(sport
->rtsirq
, imx_rtsint
, 0,
410 if (retval
) goto error_out3
;
411 set_irq_type(sport
->rtsirq
, IRQT_BOTHEDGE
);
414 * Finally, clear and enable interrupts
417 USR1((u32
)sport
->port
.membase
) = USR1_RTSD
;
418 UCR1((u32
)sport
->port
.membase
) |=
419 (UCR1_TXMPTYEN
| UCR1_RRDYEN
| UCR1_RTSDEN
| UCR1_UARTEN
);
421 UCR2((u32
)sport
->port
.membase
) |= (UCR2_RXEN
| UCR2_TXEN
);
423 * Enable modem status interrupts
425 spin_lock_irqsave(&sport
->port
.lock
,flags
);
426 imx_enable_ms(&sport
->port
);
427 spin_unlock_irqrestore(&sport
->port
.lock
,flags
);
432 free_irq(sport
->txirq
, sport
);
434 free_irq(sport
->rxirq
, sport
);
439 static void imx_shutdown(struct uart_port
*port
)
441 struct imx_port
*sport
= (struct imx_port
*)port
;
446 del_timer_sync(&sport
->timer
);
449 * Free the interrupts
451 free_irq(sport
->rtsirq
, sport
);
452 free_irq(sport
->txirq
, sport
);
453 free_irq(sport
->rxirq
, sport
);
456 * Disable all interrupts, port and break condition.
459 UCR1((u32
)sport
->port
.membase
) &=
460 ~(UCR1_TXMPTYEN
| UCR1_RRDYEN
| UCR1_RTSDEN
| UCR1_UARTEN
);
464 imx_set_termios(struct uart_port
*port
, struct termios
*termios
,
467 struct imx_port
*sport
= (struct imx_port
*)port
;
469 unsigned int ucr2
, old_ucr1
, old_txrxen
, baud
, quot
;
470 unsigned int old_csize
= old
? old
->c_cflag
& CSIZE
: CS8
;
473 * If we don't support modem control lines, don't allow
477 termios
->c_cflag
&= ~(HUPCL
| CRTSCTS
| CMSPAR
);
478 termios
->c_cflag
|= CLOCAL
;
482 * We only support CS7 and CS8.
484 while ((termios
->c_cflag
& CSIZE
) != CS7
&&
485 (termios
->c_cflag
& CSIZE
) != CS8
) {
486 termios
->c_cflag
&= ~CSIZE
;
487 termios
->c_cflag
|= old_csize
;
491 if ((termios
->c_cflag
& CSIZE
) == CS8
)
492 ucr2
= UCR2_WS
| UCR2_SRST
| UCR2_IRTS
;
494 ucr2
= UCR2_SRST
| UCR2_IRTS
;
496 if (termios
->c_cflag
& CRTSCTS
) {
501 if (termios
->c_cflag
& CSTOPB
)
503 if (termios
->c_cflag
& PARENB
) {
505 if (!(termios
->c_cflag
& PARODD
))
510 * Ask the core to calculate the divisor for us.
512 baud
= uart_get_baud_rate(port
, termios
, old
, 0, port
->uartclk
/16);
513 quot
= uart_get_divisor(port
, baud
);
515 spin_lock_irqsave(&sport
->port
.lock
, flags
);
517 sport
->port
.read_status_mask
= 0;
518 if (termios
->c_iflag
& INPCK
)
519 sport
->port
.read_status_mask
|= (URXD_FRMERR
| URXD_PRERR
);
520 if (termios
->c_iflag
& (BRKINT
| PARMRK
))
521 sport
->port
.read_status_mask
|= URXD_BRK
;
524 * Characters to ignore
526 sport
->port
.ignore_status_mask
= 0;
527 if (termios
->c_iflag
& IGNPAR
)
528 sport
->port
.ignore_status_mask
|= URXD_PRERR
;
529 if (termios
->c_iflag
& IGNBRK
) {
530 sport
->port
.ignore_status_mask
|= URXD_BRK
;
532 * If we're ignoring parity and break indicators,
533 * ignore overruns too (for real raw support).
535 if (termios
->c_iflag
& IGNPAR
)
536 sport
->port
.ignore_status_mask
|= URXD_OVRRUN
;
539 del_timer_sync(&sport
->timer
);
542 * Update the per-port timeout.
544 uart_update_timeout(port
, termios
->c_cflag
, baud
);
547 * disable interrupts and drain transmitter
549 old_ucr1
= UCR1((u32
)sport
->port
.membase
);
550 UCR1((u32
)sport
->port
.membase
) &= ~(UCR1_TXMPTYEN
| UCR1_RRDYEN
| UCR1_RTSDEN
);
552 while ( !(USR2((u32
)sport
->port
.membase
) & USR2_TXDC
))
555 /* then, disable everything */
556 old_txrxen
= UCR2((u32
)sport
->port
.membase
) & ( UCR2_TXEN
| UCR2_RXEN
);
557 UCR2((u32
)sport
->port
.membase
) &= ~( UCR2_TXEN
| UCR2_RXEN
);
559 /* set the parity, stop bits and data size */
560 UCR2((u32
)sport
->port
.membase
) = ucr2
;
562 /* set the baud rate. We assume uartclk = 16 MHz
565 * --------- = --------
568 UBIR((u32
)sport
->port
.membase
) = (baud
/ 100) - 1;
569 UBMR((u32
)sport
->port
.membase
) = 10000 - 1;
571 UCR1((u32
)sport
->port
.membase
) = old_ucr1
;
572 UCR2((u32
)sport
->port
.membase
) |= old_txrxen
;
574 if (UART_ENABLE_MS(&sport
->port
, termios
->c_cflag
))
575 imx_enable_ms(&sport
->port
);
577 spin_unlock_irqrestore(&sport
->port
.lock
, flags
);
580 static const char *imx_type(struct uart_port
*port
)
582 struct imx_port
*sport
= (struct imx_port
*)port
;
584 return sport
->port
.type
== PORT_IMX
? "IMX" : NULL
;
588 * Release the memory region(s) being used by 'port'.
590 static void imx_release_port(struct uart_port
*port
)
592 struct imx_port
*sport
= (struct imx_port
*)port
;
594 release_mem_region(sport
->port
.mapbase
, UART_PORT_SIZE
);
598 * Request the memory region(s) being used by 'port'.
600 static int imx_request_port(struct uart_port
*port
)
602 struct imx_port
*sport
= (struct imx_port
*)port
;
604 return request_mem_region(sport
->port
.mapbase
, UART_PORT_SIZE
,
605 "imx-uart") != NULL
? 0 : -EBUSY
;
609 * Configure/autoconfigure the port.
611 static void imx_config_port(struct uart_port
*port
, int flags
)
613 struct imx_port
*sport
= (struct imx_port
*)port
;
615 if (flags
& UART_CONFIG_TYPE
&&
616 imx_request_port(&sport
->port
) == 0)
617 sport
->port
.type
= PORT_IMX
;
621 * Verify the new serial_struct (for TIOCSSERIAL).
622 * The only change we allow are to the flags and type, and
623 * even then only between PORT_IMX and PORT_UNKNOWN
626 imx_verify_port(struct uart_port
*port
, struct serial_struct
*ser
)
628 struct imx_port
*sport
= (struct imx_port
*)port
;
631 if (ser
->type
!= PORT_UNKNOWN
&& ser
->type
!= PORT_IMX
)
633 if (sport
->port
.irq
!= ser
->irq
)
635 if (ser
->io_type
!= UPIO_MEM
)
637 if (sport
->port
.uartclk
/ 16 != ser
->baud_base
)
639 if ((void *)sport
->port
.mapbase
!= ser
->iomem_base
)
641 if (sport
->port
.iobase
!= ser
->port
)
648 static struct uart_ops imx_pops
= {
649 .tx_empty
= imx_tx_empty
,
650 .set_mctrl
= imx_set_mctrl
,
651 .get_mctrl
= imx_get_mctrl
,
652 .stop_tx
= imx_stop_tx
,
653 .start_tx
= imx_start_tx
,
654 .stop_rx
= imx_stop_rx
,
655 .enable_ms
= imx_enable_ms
,
656 .break_ctl
= imx_break_ctl
,
657 .startup
= imx_startup
,
658 .shutdown
= imx_shutdown
,
659 .set_termios
= imx_set_termios
,
661 .release_port
= imx_release_port
,
662 .request_port
= imx_request_port
,
663 .config_port
= imx_config_port
,
664 .verify_port
= imx_verify_port
,
667 static struct imx_port imx_ports
[] = {
669 .txirq
= UART1_MINT_TX
,
670 .rxirq
= UART1_MINT_RX
,
671 .rtsirq
= UART1_MINT_RTS
,
674 .iotype
= SERIAL_IO_MEM
,
675 .membase
= (void *)IMX_UART1_BASE
,
676 .mapbase
= IMX_UART1_BASE
, /* FIXME */
677 .irq
= UART1_MINT_RX
,
680 .flags
= ASYNC_BOOT_AUTOCONF
,
685 .txirq
= UART2_MINT_TX
,
686 .rxirq
= UART2_MINT_RX
,
687 .rtsirq
= UART2_MINT_RTS
,
690 .iotype
= SERIAL_IO_MEM
,
691 .membase
= (void *)IMX_UART2_BASE
,
692 .mapbase
= IMX_UART2_BASE
, /* FIXME */
693 .irq
= UART2_MINT_RX
,
696 .flags
= ASYNC_BOOT_AUTOCONF
,
704 * Setup the IMX serial ports.
705 * Note also that we support "console=ttySMXx" where "x" is either 0 or 1.
706 * Which serial port this ends up being depends on the machine you're
707 * running this kernel on. I'm not convinced that this is a good idea,
708 * but that's the way it traditionally works.
711 static void __init
imx_init_ports(void)
713 static int first
= 1;
720 for (i
= 0; i
< ARRAY_SIZE(imx_ports
); i
++) {
721 init_timer(&imx_ports
[i
].timer
);
722 imx_ports
[i
].timer
.function
= imx_timeout
;
723 imx_ports
[i
].timer
.data
= (unsigned long)&imx_ports
[i
];
726 imx_gpio_mode(PC9_PF_UART1_CTS
);
727 imx_gpio_mode(PC10_PF_UART1_RTS
);
728 imx_gpio_mode(PC11_PF_UART1_TXD
);
729 imx_gpio_mode(PC12_PF_UART1_RXD
);
730 imx_gpio_mode(PB28_PF_UART2_CTS
);
731 imx_gpio_mode(PB29_PF_UART2_RTS
);
733 imx_gpio_mode(PB30_PF_UART2_TXD
);
734 imx_gpio_mode(PB31_PF_UART2_RXD
);
736 #if 0 /* We don't need these, on the mx1 the _modem_ side of the uart
739 imx_gpio_mode(PD7_AF_UART2_DTR
);
740 imx_gpio_mode(PD8_AF_UART2_DCD
);
741 imx_gpio_mode(PD9_AF_UART2_RI
);
742 imx_gpio_mode(PD10_AF_UART2_DSR
);
748 #ifdef CONFIG_SERIAL_IMX_CONSOLE
751 * Interrupts are disabled on entering
754 imx_console_write(struct console
*co
, const char *s
, unsigned int count
)
756 struct imx_port
*sport
= &imx_ports
[co
->index
];
757 unsigned int old_ucr1
, old_ucr2
, i
;
760 * First, save UCR1/2 and then disable interrupts
762 old_ucr1
= UCR1((u32
)sport
->port
.membase
);
763 old_ucr2
= UCR2((u32
)sport
->port
.membase
);
765 UCR1((u32
)sport
->port
.membase
) =
766 (old_ucr1
| UCR1_UARTCLKEN
| UCR1_UARTEN
)
767 & ~(UCR1_TXMPTYEN
| UCR1_RRDYEN
| UCR1_RTSDEN
);
768 UCR2((u32
)sport
->port
.membase
) = old_ucr2
| UCR2_TXEN
;
771 * Now, do each character
773 for (i
= 0; i
< count
; i
++) {
775 while ((UTS((u32
)sport
->port
.membase
) & UTS_TXFULL
))
778 URTX0((u32
)sport
->port
.membase
) = s
[i
];
781 while ((UTS((u32
)sport
->port
.membase
) & UTS_TXFULL
))
783 URTX0((u32
)sport
->port
.membase
) = '\r';
788 * Finally, wait for transmitter to become empty
791 while (!(USR2((u32
)sport
->port
.membase
) & USR2_TXDC
));
793 UCR1((u32
)sport
->port
.membase
) = old_ucr1
;
794 UCR2((u32
)sport
->port
.membase
) = old_ucr2
;
798 * If the port was already initialised (eg, by a boot loader),
799 * try to determine the current setup.
802 imx_console_get_options(struct imx_port
*sport
, int *baud
,
803 int *parity
, int *bits
)
806 if ( UCR1((u32
)sport
->port
.membase
) | UCR1_UARTEN
) {
807 /* ok, the port was enabled */
808 unsigned int ucr2
, ubir
,ubmr
, uartclk
;
809 unsigned int baud_raw
;
810 unsigned int ucfr_rfdiv
;
812 ucr2
= UCR2((u32
)sport
->port
.membase
);
815 if (ucr2
& UCR2_PREN
) {
816 if (ucr2
& UCR2_PROE
)
827 ubir
= UBIR((u32
)sport
->port
.membase
) & 0xffff;
828 ubmr
= UBMR((u32
)sport
->port
.membase
) & 0xffff;
831 ucfr_rfdiv
= (UFCR((u32
)sport
->port
.membase
) & UFCR_RFDIV
) >> 7;
835 ucfr_rfdiv
= 6 - ucfr_rfdiv
;
837 uartclk
= imx_get_perclk1();
838 uartclk
/= ucfr_rfdiv
;
841 * The next code provides exact computation of
842 * baud_raw = round(((uartclk/16) * (ubir + 1)) / (ubmr + 1))
843 * without need of float support or long long division,
844 * which would be required to prevent 32bit arithmetic overflow
846 unsigned int mul
= ubir
+ 1;
847 unsigned int div
= 16 * (ubmr
+ 1);
848 unsigned int rem
= uartclk
% div
;
850 baud_raw
= (uartclk
/ div
) * mul
;
851 baud_raw
+= (rem
* mul
+ div
/ 2) / div
;
852 *baud
= (baud_raw
+ 50) / 100 * 100;
855 if(*baud
!= baud_raw
)
856 printk(KERN_INFO
"Serial: Console IMX rounded baud rate from %d to %d\n",
862 imx_console_setup(struct console
*co
, char *options
)
864 struct imx_port
*sport
;
871 * Check whether an invalid uart number has been specified, and
872 * if so, search for the first available port that does have
875 if (co
->index
== -1 || co
->index
>= ARRAY_SIZE(imx_ports
))
877 sport
= &imx_ports
[co
->index
];
880 uart_parse_options(options
, &baud
, &parity
, &bits
, &flow
);
882 imx_console_get_options(sport
, &baud
, &parity
, &bits
);
884 imx_setup_ufcr(sport
, 0);
886 return uart_set_options(&sport
->port
, co
, baud
, parity
, bits
, flow
);
889 static struct uart_driver imx_reg
;
890 static struct console imx_console
= {
892 .write
= imx_console_write
,
893 .device
= uart_console_device
,
894 .setup
= imx_console_setup
,
895 .flags
= CON_PRINTBUFFER
,
900 static int __init
imx_rs_console_init(void)
903 register_console(&imx_console
);
906 console_initcall(imx_rs_console_init
);
908 #define IMX_CONSOLE &imx_console
910 #define IMX_CONSOLE NULL
913 static struct uart_driver imx_reg
= {
914 .owner
= THIS_MODULE
,
915 .driver_name
= DRIVER_NAME
,
916 .dev_name
= "ttySMX",
917 .devfs_name
= "ttsmx/",
918 .major
= SERIAL_IMX_MAJOR
,
919 .minor
= MINOR_START
,
920 .nr
= ARRAY_SIZE(imx_ports
),
924 static int serial_imx_suspend(struct platform_device
*dev
, pm_message_t state
)
926 struct imx_port
*sport
= platform_get_drvdata(dev
);
929 uart_suspend_port(&imx_reg
, &sport
->port
);
934 static int serial_imx_resume(struct platform_device
*dev
)
936 struct imx_port
*sport
= platform_get_drvdata(dev
);
939 uart_resume_port(&imx_reg
, &sport
->port
);
944 static int serial_imx_probe(struct platform_device
*dev
)
946 imx_ports
[dev
->id
].port
.dev
= &dev
->dev
;
947 uart_add_one_port(&imx_reg
, &imx_ports
[dev
->id
].port
);
948 platform_set_drvdata(dev
, &imx_ports
[dev
->id
]);
952 static int serial_imx_remove(struct platform_device
*dev
)
954 struct imx_port
*sport
= platform_get_drvdata(dev
);
956 platform_set_drvdata(dev
, NULL
);
959 uart_remove_one_port(&imx_reg
, &sport
->port
);
964 static struct platform_driver serial_imx_driver
= {
965 .probe
= serial_imx_probe
,
966 .remove
= serial_imx_remove
,
968 .suspend
= serial_imx_suspend
,
969 .resume
= serial_imx_resume
,
975 static int __init
imx_serial_init(void)
979 printk(KERN_INFO
"Serial: IMX driver\n");
983 ret
= uart_register_driver(&imx_reg
);
987 ret
= platform_driver_register(&serial_imx_driver
);
989 uart_unregister_driver(&imx_reg
);
994 static void __exit
imx_serial_exit(void)
996 uart_unregister_driver(&imx_reg
);
997 platform_driver_unregister(&serial_imx_driver
);
1000 module_init(imx_serial_init
);
1001 module_exit(imx_serial_exit
);
1003 MODULE_AUTHOR("Sascha Hauer");
1004 MODULE_DESCRIPTION("IMX generic serial port driver");
1005 MODULE_LICENSE("GPL");