1 // SPDX-License-Identifier: GPL-2.0+
2 /****************************************************************************/
5 * mcf.c -- Freescale ColdFire UART driver
7 * (C) Copyright 2003-2007, Greg Ungerer <gerg@uclinux.org>
10 /****************************************************************************/
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/interrupt.h>
15 #include <linux/module.h>
16 #include <linux/console.h>
17 #include <linux/tty.h>
18 #include <linux/tty_flip.h>
19 #include <linux/serial.h>
20 #include <linux/serial_core.h>
22 #include <linux/uaccess.h>
23 #include <linux/platform_device.h>
24 #include <asm/coldfire.h>
25 #include <asm/mcfsim.h>
26 #include <asm/mcfuart.h>
27 #include <asm/nettel.h>
29 /****************************************************************************/
32 * Some boards implement the DTR/DCD lines using GPIO lines, most
33 * don't. Dummy out the access macros for those that don't. Those
34 * that do should define these macros somewhere in there board
35 * specific inlude files.
37 #if !defined(mcf_getppdcd)
38 #define mcf_getppdcd(p) (1)
40 #if !defined(mcf_getppdtr)
41 #define mcf_getppdtr(p) (1)
43 #if !defined(mcf_setppdtr)
44 #define mcf_setppdtr(p, v) do { } while (0)
47 /****************************************************************************/
50 * Local per-uart structure.
53 struct uart_port port
;
54 unsigned int sigs
; /* Local copy of line sigs */
55 unsigned char imr
; /* Local IMR mirror */
58 /****************************************************************************/
60 static unsigned int mcf_tx_empty(struct uart_port
*port
)
62 return (readb(port
->membase
+ MCFUART_USR
) & MCFUART_USR_TXEMPTY
) ?
66 /****************************************************************************/
68 static unsigned int mcf_get_mctrl(struct uart_port
*port
)
70 struct mcf_uart
*pp
= container_of(port
, struct mcf_uart
, port
);
73 sigs
= (readb(port
->membase
+ MCFUART_UIPR
) & MCFUART_UIPR_CTS
) ?
75 sigs
|= (pp
->sigs
& TIOCM_RTS
);
76 sigs
|= (mcf_getppdcd(port
->line
) ? TIOCM_CD
: 0);
77 sigs
|= (mcf_getppdtr(port
->line
) ? TIOCM_DTR
: 0);
82 /****************************************************************************/
84 static void mcf_set_mctrl(struct uart_port
*port
, unsigned int sigs
)
86 struct mcf_uart
*pp
= container_of(port
, struct mcf_uart
, port
);
89 mcf_setppdtr(port
->line
, (sigs
& TIOCM_DTR
));
91 writeb(MCFUART_UOP_RTS
, port
->membase
+ MCFUART_UOP1
);
93 writeb(MCFUART_UOP_RTS
, port
->membase
+ MCFUART_UOP0
);
96 /****************************************************************************/
98 static void mcf_start_tx(struct uart_port
*port
)
100 struct mcf_uart
*pp
= container_of(port
, struct mcf_uart
, port
);
102 if (port
->rs485
.flags
& SER_RS485_ENABLED
) {
103 /* Enable Transmitter */
104 writeb(MCFUART_UCR_TXENABLE
, port
->membase
+ MCFUART_UCR
);
105 /* Manually assert RTS */
106 writeb(MCFUART_UOP_RTS
, port
->membase
+ MCFUART_UOP1
);
108 pp
->imr
|= MCFUART_UIR_TXREADY
;
109 writeb(pp
->imr
, port
->membase
+ MCFUART_UIMR
);
112 /****************************************************************************/
114 static void mcf_stop_tx(struct uart_port
*port
)
116 struct mcf_uart
*pp
= container_of(port
, struct mcf_uart
, port
);
118 pp
->imr
&= ~MCFUART_UIR_TXREADY
;
119 writeb(pp
->imr
, port
->membase
+ MCFUART_UIMR
);
122 /****************************************************************************/
124 static void mcf_stop_rx(struct uart_port
*port
)
126 struct mcf_uart
*pp
= container_of(port
, struct mcf_uart
, port
);
128 pp
->imr
&= ~MCFUART_UIR_RXREADY
;
129 writeb(pp
->imr
, port
->membase
+ MCFUART_UIMR
);
132 /****************************************************************************/
134 static void mcf_break_ctl(struct uart_port
*port
, int break_state
)
138 spin_lock_irqsave(&port
->lock
, flags
);
139 if (break_state
== -1)
140 writeb(MCFUART_UCR_CMDBREAKSTART
, port
->membase
+ MCFUART_UCR
);
142 writeb(MCFUART_UCR_CMDBREAKSTOP
, port
->membase
+ MCFUART_UCR
);
143 spin_unlock_irqrestore(&port
->lock
, flags
);
146 /****************************************************************************/
148 static int mcf_startup(struct uart_port
*port
)
150 struct mcf_uart
*pp
= container_of(port
, struct mcf_uart
, port
);
153 spin_lock_irqsave(&port
->lock
, flags
);
155 /* Reset UART, get it into known state... */
156 writeb(MCFUART_UCR_CMDRESETRX
, port
->membase
+ MCFUART_UCR
);
157 writeb(MCFUART_UCR_CMDRESETTX
, port
->membase
+ MCFUART_UCR
);
159 /* Enable the UART transmitter and receiver */
160 writeb(MCFUART_UCR_RXENABLE
| MCFUART_UCR_TXENABLE
,
161 port
->membase
+ MCFUART_UCR
);
163 /* Enable RX interrupts now */
164 pp
->imr
= MCFUART_UIR_RXREADY
;
165 writeb(pp
->imr
, port
->membase
+ MCFUART_UIMR
);
167 spin_unlock_irqrestore(&port
->lock
, flags
);
172 /****************************************************************************/
174 static void mcf_shutdown(struct uart_port
*port
)
176 struct mcf_uart
*pp
= container_of(port
, struct mcf_uart
, port
);
179 spin_lock_irqsave(&port
->lock
, flags
);
181 /* Disable all interrupts now */
183 writeb(pp
->imr
, port
->membase
+ MCFUART_UIMR
);
185 /* Disable UART transmitter and receiver */
186 writeb(MCFUART_UCR_CMDRESETRX
, port
->membase
+ MCFUART_UCR
);
187 writeb(MCFUART_UCR_CMDRESETTX
, port
->membase
+ MCFUART_UCR
);
189 spin_unlock_irqrestore(&port
->lock
, flags
);
192 /****************************************************************************/
194 static void mcf_set_termios(struct uart_port
*port
, struct ktermios
*termios
,
195 struct ktermios
*old
)
198 unsigned int baud
, baudclk
;
199 #if defined(CONFIG_M5272)
202 unsigned char mr1
, mr2
;
204 baud
= uart_get_baud_rate(port
, termios
, old
, 0, 230400);
205 #if defined(CONFIG_M5272)
206 baudclk
= (MCF_BUSCLK
/ baud
) / 32;
207 baudfr
= (((MCF_BUSCLK
/ baud
) + 1) / 2) % 16;
209 baudclk
= ((MCF_BUSCLK
/ baud
) + 16) / 32;
212 mr1
= MCFUART_MR1_RXIRQRDY
| MCFUART_MR1_RXERRCHAR
;
215 switch (termios
->c_cflag
& CSIZE
) {
216 case CS5
: mr1
|= MCFUART_MR1_CS5
; break;
217 case CS6
: mr1
|= MCFUART_MR1_CS6
; break;
218 case CS7
: mr1
|= MCFUART_MR1_CS7
; break;
220 default: mr1
|= MCFUART_MR1_CS8
; break;
223 if (termios
->c_cflag
& PARENB
) {
224 if (termios
->c_cflag
& CMSPAR
) {
225 if (termios
->c_cflag
& PARODD
)
226 mr1
|= MCFUART_MR1_PARITYMARK
;
228 mr1
|= MCFUART_MR1_PARITYSPACE
;
230 if (termios
->c_cflag
& PARODD
)
231 mr1
|= MCFUART_MR1_PARITYODD
;
233 mr1
|= MCFUART_MR1_PARITYEVEN
;
236 mr1
|= MCFUART_MR1_PARITYNONE
;
240 * FIXME: port->read_status_mask and port->ignore_status_mask
241 * need to be initialized based on termios settings for
242 * INPCK, IGNBRK, IGNPAR, PARMRK, BRKINT
245 if (termios
->c_cflag
& CSTOPB
)
246 mr2
|= MCFUART_MR2_STOP2
;
248 mr2
|= MCFUART_MR2_STOP1
;
250 if (termios
->c_cflag
& CRTSCTS
) {
251 mr1
|= MCFUART_MR1_RXRTS
;
252 mr2
|= MCFUART_MR2_TXCTS
;
255 spin_lock_irqsave(&port
->lock
, flags
);
256 if (port
->rs485
.flags
& SER_RS485_ENABLED
) {
257 dev_dbg(port
->dev
, "Setting UART to RS485\n");
258 mr2
|= MCFUART_MR2_TXRTS
;
261 uart_update_timeout(port
, termios
->c_cflag
, baud
);
262 writeb(MCFUART_UCR_CMDRESETRX
, port
->membase
+ MCFUART_UCR
);
263 writeb(MCFUART_UCR_CMDRESETTX
, port
->membase
+ MCFUART_UCR
);
264 writeb(MCFUART_UCR_CMDRESETMRPTR
, port
->membase
+ MCFUART_UCR
);
265 writeb(mr1
, port
->membase
+ MCFUART_UMR
);
266 writeb(mr2
, port
->membase
+ MCFUART_UMR
);
267 writeb((baudclk
& 0xff00) >> 8, port
->membase
+ MCFUART_UBG1
);
268 writeb((baudclk
& 0xff), port
->membase
+ MCFUART_UBG2
);
269 #if defined(CONFIG_M5272)
270 writeb((baudfr
& 0x0f), port
->membase
+ MCFUART_UFPD
);
272 writeb(MCFUART_UCSR_RXCLKTIMER
| MCFUART_UCSR_TXCLKTIMER
,
273 port
->membase
+ MCFUART_UCSR
);
274 writeb(MCFUART_UCR_RXENABLE
| MCFUART_UCR_TXENABLE
,
275 port
->membase
+ MCFUART_UCR
);
276 spin_unlock_irqrestore(&port
->lock
, flags
);
279 /****************************************************************************/
281 static void mcf_rx_chars(struct mcf_uart
*pp
)
283 struct uart_port
*port
= &pp
->port
;
284 unsigned char status
, ch
, flag
;
286 while ((status
= readb(port
->membase
+ MCFUART_USR
)) & MCFUART_USR_RXREADY
) {
287 ch
= readb(port
->membase
+ MCFUART_URB
);
291 if (status
& MCFUART_USR_RXERR
) {
292 writeb(MCFUART_UCR_CMDRESETERR
,
293 port
->membase
+ MCFUART_UCR
);
295 if (status
& MCFUART_USR_RXBREAK
) {
297 if (uart_handle_break(port
))
299 } else if (status
& MCFUART_USR_RXPARITY
) {
300 port
->icount
.parity
++;
301 } else if (status
& MCFUART_USR_RXOVERRUN
) {
302 port
->icount
.overrun
++;
303 } else if (status
& MCFUART_USR_RXFRAMING
) {
304 port
->icount
.frame
++;
307 status
&= port
->read_status_mask
;
309 if (status
& MCFUART_USR_RXBREAK
)
311 else if (status
& MCFUART_USR_RXPARITY
)
313 else if (status
& MCFUART_USR_RXFRAMING
)
317 if (uart_handle_sysrq_char(port
, ch
))
319 uart_insert_char(port
, status
, MCFUART_USR_RXOVERRUN
, ch
, flag
);
322 spin_unlock(&port
->lock
);
323 tty_flip_buffer_push(&port
->state
->port
);
324 spin_lock(&port
->lock
);
327 /****************************************************************************/
329 static void mcf_tx_chars(struct mcf_uart
*pp
)
331 struct uart_port
*port
= &pp
->port
;
332 struct circ_buf
*xmit
= &port
->state
->xmit
;
335 /* Send special char - probably flow control */
336 writeb(port
->x_char
, port
->membase
+ MCFUART_UTB
);
342 while (readb(port
->membase
+ MCFUART_USR
) & MCFUART_USR_TXREADY
) {
343 if (xmit
->head
== xmit
->tail
)
345 writeb(xmit
->buf
[xmit
->tail
], port
->membase
+ MCFUART_UTB
);
346 xmit
->tail
= (xmit
->tail
+ 1) & (UART_XMIT_SIZE
-1);
350 if (uart_circ_chars_pending(xmit
) < WAKEUP_CHARS
)
351 uart_write_wakeup(port
);
353 if (xmit
->head
== xmit
->tail
) {
354 pp
->imr
&= ~MCFUART_UIR_TXREADY
;
355 writeb(pp
->imr
, port
->membase
+ MCFUART_UIMR
);
356 /* Disable TX to negate RTS automatically */
357 if (port
->rs485
.flags
& SER_RS485_ENABLED
)
358 writeb(MCFUART_UCR_TXDISABLE
,
359 port
->membase
+ MCFUART_UCR
);
363 /****************************************************************************/
365 static irqreturn_t
mcf_interrupt(int irq
, void *data
)
367 struct uart_port
*port
= data
;
368 struct mcf_uart
*pp
= container_of(port
, struct mcf_uart
, port
);
370 irqreturn_t ret
= IRQ_NONE
;
372 isr
= readb(port
->membase
+ MCFUART_UISR
) & pp
->imr
;
374 spin_lock(&port
->lock
);
375 if (isr
& MCFUART_UIR_RXREADY
) {
379 if (isr
& MCFUART_UIR_TXREADY
) {
383 spin_unlock(&port
->lock
);
388 /****************************************************************************/
390 static void mcf_config_port(struct uart_port
*port
, int flags
)
392 port
->type
= PORT_MCF
;
393 port
->fifosize
= MCFUART_TXFIFOSIZE
;
395 /* Clear mask, so no surprise interrupts. */
396 writeb(0, port
->membase
+ MCFUART_UIMR
);
398 if (request_irq(port
->irq
, mcf_interrupt
, 0, "UART", port
))
399 printk(KERN_ERR
"MCF: unable to attach ColdFire UART %d "
400 "interrupt vector=%d\n", port
->line
, port
->irq
);
403 /****************************************************************************/
405 static const char *mcf_type(struct uart_port
*port
)
407 return (port
->type
== PORT_MCF
) ? "ColdFire UART" : NULL
;
410 /****************************************************************************/
412 static int mcf_request_port(struct uart_port
*port
)
414 /* UARTs always present */
418 /****************************************************************************/
420 static void mcf_release_port(struct uart_port
*port
)
422 /* Nothing to release... */
425 /****************************************************************************/
427 static int mcf_verify_port(struct uart_port
*port
, struct serial_struct
*ser
)
429 if ((ser
->type
!= PORT_UNKNOWN
) && (ser
->type
!= PORT_MCF
))
434 /****************************************************************************/
436 /* Enable or disable the RS485 support */
437 static int mcf_config_rs485(struct uart_port
*port
, struct serial_rs485
*rs485
)
439 unsigned char mr1
, mr2
;
441 /* Get mode registers */
442 mr1
= readb(port
->membase
+ MCFUART_UMR
);
443 mr2
= readb(port
->membase
+ MCFUART_UMR
);
444 if (rs485
->flags
& SER_RS485_ENABLED
) {
445 dev_dbg(port
->dev
, "Setting UART to RS485\n");
446 /* Automatically negate RTS after TX completes */
447 mr2
|= MCFUART_MR2_TXRTS
;
449 dev_dbg(port
->dev
, "Setting UART to RS232\n");
450 mr2
&= ~MCFUART_MR2_TXRTS
;
452 writeb(mr1
, port
->membase
+ MCFUART_UMR
);
453 writeb(mr2
, port
->membase
+ MCFUART_UMR
);
454 port
->rs485
= *rs485
;
459 /****************************************************************************/
462 * Define the basic serial functions we support.
464 static const struct uart_ops mcf_uart_ops
= {
465 .tx_empty
= mcf_tx_empty
,
466 .get_mctrl
= mcf_get_mctrl
,
467 .set_mctrl
= mcf_set_mctrl
,
468 .start_tx
= mcf_start_tx
,
469 .stop_tx
= mcf_stop_tx
,
470 .stop_rx
= mcf_stop_rx
,
471 .break_ctl
= mcf_break_ctl
,
472 .startup
= mcf_startup
,
473 .shutdown
= mcf_shutdown
,
474 .set_termios
= mcf_set_termios
,
476 .request_port
= mcf_request_port
,
477 .release_port
= mcf_release_port
,
478 .config_port
= mcf_config_port
,
479 .verify_port
= mcf_verify_port
,
482 static struct mcf_uart mcf_ports
[4];
484 #define MCF_MAXPORTS ARRAY_SIZE(mcf_ports)
486 /****************************************************************************/
487 #if defined(CONFIG_SERIAL_MCF_CONSOLE)
488 /****************************************************************************/
490 int __init
early_mcf_setup(struct mcf_platform_uart
*platp
)
492 struct uart_port
*port
;
495 for (i
= 0; ((i
< MCF_MAXPORTS
) && (platp
[i
].mapbase
)); i
++) {
496 port
= &mcf_ports
[i
].port
;
499 port
->type
= PORT_MCF
;
500 port
->mapbase
= platp
[i
].mapbase
;
501 port
->membase
= (platp
[i
].membase
) ? platp
[i
].membase
:
502 (unsigned char __iomem
*) port
->mapbase
;
503 port
->iotype
= SERIAL_IO_MEM
;
504 port
->irq
= platp
[i
].irq
;
505 port
->uartclk
= MCF_BUSCLK
;
506 port
->flags
= UPF_BOOT_AUTOCONF
;
507 port
->rs485_config
= mcf_config_rs485
;
508 port
->ops
= &mcf_uart_ops
;
514 /****************************************************************************/
516 static void mcf_console_putc(struct console
*co
, const char c
)
518 struct uart_port
*port
= &(mcf_ports
+ co
->index
)->port
;
521 for (i
= 0; (i
< 0x10000); i
++) {
522 if (readb(port
->membase
+ MCFUART_USR
) & MCFUART_USR_TXREADY
)
525 writeb(c
, port
->membase
+ MCFUART_UTB
);
526 for (i
= 0; (i
< 0x10000); i
++) {
527 if (readb(port
->membase
+ MCFUART_USR
) & MCFUART_USR_TXREADY
)
532 /****************************************************************************/
534 static void mcf_console_write(struct console
*co
, const char *s
, unsigned int count
)
536 for (; (count
); count
--, s
++) {
537 mcf_console_putc(co
, *s
);
539 mcf_console_putc(co
, '\r');
543 /****************************************************************************/
545 static int __init
mcf_console_setup(struct console
*co
, char *options
)
547 struct uart_port
*port
;
548 int baud
= CONFIG_SERIAL_MCF_BAUDRATE
;
553 if ((co
->index
< 0) || (co
->index
>= MCF_MAXPORTS
))
555 port
= &mcf_ports
[co
->index
].port
;
556 if (port
->membase
== 0)
560 uart_parse_options(options
, &baud
, &parity
, &bits
, &flow
);
562 return uart_set_options(port
, co
, baud
, parity
, bits
, flow
);
565 /****************************************************************************/
567 static struct uart_driver mcf_driver
;
569 static struct console mcf_console
= {
571 .write
= mcf_console_write
,
572 .device
= uart_console_device
,
573 .setup
= mcf_console_setup
,
574 .flags
= CON_PRINTBUFFER
,
579 static int __init
mcf_console_init(void)
581 register_console(&mcf_console
);
585 console_initcall(mcf_console_init
);
587 #define MCF_CONSOLE &mcf_console
589 /****************************************************************************/
591 /****************************************************************************/
593 #define MCF_CONSOLE NULL
595 /****************************************************************************/
596 #endif /* CONFIG_SERIAL_MCF_CONSOLE */
597 /****************************************************************************/
600 * Define the mcf UART driver structure.
602 static struct uart_driver mcf_driver
= {
603 .owner
= THIS_MODULE
,
604 .driver_name
= "mcf",
612 /****************************************************************************/
614 static int mcf_probe(struct platform_device
*pdev
)
616 struct mcf_platform_uart
*platp
= dev_get_platdata(&pdev
->dev
);
617 struct uart_port
*port
;
620 for (i
= 0; ((i
< MCF_MAXPORTS
) && (platp
[i
].mapbase
)); i
++) {
621 port
= &mcf_ports
[i
].port
;
624 port
->type
= PORT_MCF
;
625 port
->mapbase
= platp
[i
].mapbase
;
626 port
->membase
= (platp
[i
].membase
) ? platp
[i
].membase
:
627 (unsigned char __iomem
*) platp
[i
].mapbase
;
628 port
->dev
= &pdev
->dev
;
629 port
->iotype
= SERIAL_IO_MEM
;
630 port
->irq
= platp
[i
].irq
;
631 port
->uartclk
= MCF_BUSCLK
;
632 port
->ops
= &mcf_uart_ops
;
633 port
->flags
= UPF_BOOT_AUTOCONF
;
634 port
->rs485_config
= mcf_config_rs485
;
636 uart_add_one_port(&mcf_driver
, port
);
642 /****************************************************************************/
644 static int mcf_remove(struct platform_device
*pdev
)
646 struct uart_port
*port
;
649 for (i
= 0; (i
< MCF_MAXPORTS
); i
++) {
650 port
= &mcf_ports
[i
].port
;
652 uart_remove_one_port(&mcf_driver
, port
);
658 /****************************************************************************/
660 static struct platform_driver mcf_platform_driver
= {
662 .remove
= mcf_remove
,
668 /****************************************************************************/
670 static int __init
mcf_init(void)
674 printk("ColdFire internal UART serial driver\n");
676 rc
= uart_register_driver(&mcf_driver
);
679 rc
= platform_driver_register(&mcf_platform_driver
);
681 uart_unregister_driver(&mcf_driver
);
687 /****************************************************************************/
689 static void __exit
mcf_exit(void)
691 platform_driver_unregister(&mcf_platform_driver
);
692 uart_unregister_driver(&mcf_driver
);
695 /****************************************************************************/
697 module_init(mcf_init
);
698 module_exit(mcf_exit
);
700 MODULE_AUTHOR("Greg Ungerer <gerg@uclinux.org>");
701 MODULE_DESCRIPTION("Freescale ColdFire UART driver");
702 MODULE_LICENSE("GPL");
703 MODULE_ALIAS("platform:mcfuart");
705 /****************************************************************************/