2 * SC268xx.c: Serial driver for Philiphs SC2681/SC2692 devices.
4 * Copyright (C) 2006,2007 Thomas Bogendörfer (tsbogend@alpha.franken.de)
7 #include <linux/module.h>
8 #include <linux/kernel.h>
9 #include <linux/errno.h>
10 #include <linux/tty.h>
11 #include <linux/tty_flip.h>
12 #include <linux/major.h>
13 #include <linux/circ_buf.h>
14 #include <linux/serial.h>
15 #include <linux/sysrq.h>
16 #include <linux/console.h>
17 #include <linux/spinlock.h>
18 #include <linux/slab.h>
19 #include <linux/delay.h>
20 #include <linux/init.h>
21 #include <linux/platform_device.h>
22 #include <linux/irq.h>
24 #if defined(CONFIG_MAGIC_SYSRQ)
28 #include <linux/serial_core.h>
30 #define SC26XX_MAJOR 204
31 #define SC26XX_MINOR_START 205
34 struct uart_sc26xx_port
{
35 struct uart_port port
[2];
45 /* register common to both ports */
52 #define WR_OPR_SET 0x38
53 #define WR_OPR_CLR 0x3C
55 /* access common register */
56 #define READ_SC(p, r) readb((p)->membase + RD_##r)
57 #define WRITE_SC(p, r, v) writeb((v), (p)->membase + WR_##r)
59 /* register per port */
60 #define RD_PORT_MRx 0x00
61 #define RD_PORT_SR 0x04
62 #define RD_PORT_RHR 0x0c
64 #define WR_PORT_MRx 0x00
65 #define WR_PORT_CSR 0x04
66 #define WR_PORT_CR 0x08
67 #define WR_PORT_THR 0x0c
70 #define SR_BREAK (1 << 7)
71 #define SR_FRAME (1 << 6)
72 #define SR_PARITY (1 << 5)
73 #define SR_OVERRUN (1 << 4)
74 #define SR_TXRDY (1 << 2)
75 #define SR_RXRDY (1 << 0)
77 #define CR_RES_MR (1 << 4)
78 #define CR_RES_RX (2 << 4)
79 #define CR_RES_TX (3 << 4)
80 #define CR_STRT_BRK (6 << 4)
81 #define CR_STOP_BRK (7 << 4)
82 #define CR_DIS_TX (1 << 3)
83 #define CR_ENA_TX (1 << 2)
84 #define CR_DIS_RX (1 << 1)
85 #define CR_ENA_RX (1 << 0)
88 #define ISR_RXRDYB (1 << 5)
89 #define ISR_TXRDYB (1 << 4)
90 #define ISR_RXRDYA (1 << 1)
91 #define ISR_TXRDYA (1 << 0)
94 #define IMR_RXRDY (1 << 1)
95 #define IMR_TXRDY (1 << 0)
97 /* access port register */
98 static inline u8
read_sc_port(struct uart_port
*p
, u8 reg
)
100 return readb(p
->membase
+ p
->line
* 0x20 + reg
);
103 static inline void write_sc_port(struct uart_port
*p
, u8 reg
, u8 val
)
105 writeb(val
, p
->membase
+ p
->line
* 0x20 + reg
);
108 #define READ_SC_PORT(p, r) read_sc_port(p, RD_PORT_##r)
109 #define WRITE_SC_PORT(p, r, v) write_sc_port(p, WR_PORT_##r, v)
111 static void sc26xx_enable_irq(struct uart_port
*port
, int mask
)
113 struct uart_sc26xx_port
*up
;
114 int line
= port
->line
;
117 up
= container_of(port
, struct uart_sc26xx_port
, port
[0]);
119 up
->imr
|= mask
<< (line
* 4);
120 WRITE_SC(port
, IMR
, up
->imr
);
123 static void sc26xx_disable_irq(struct uart_port
*port
, int mask
)
125 struct uart_sc26xx_port
*up
;
126 int line
= port
->line
;
129 up
= container_of(port
, struct uart_sc26xx_port
, port
[0]);
131 up
->imr
&= ~(mask
<< (line
* 4));
132 WRITE_SC(port
, IMR
, up
->imr
);
135 static struct tty_struct
*receive_chars(struct uart_port
*port
)
137 struct tty_struct
*tty
= NULL
;
143 if (port
->state
!= NULL
) /* Unopened serial console */
144 tty
= port
->state
->port
.tty
;
146 while (limit
-- > 0) {
147 status
= READ_SC_PORT(port
, SR
);
148 if (!(status
& SR_RXRDY
))
150 ch
= READ_SC_PORT(port
, RHR
);
155 if (unlikely(status
& (SR_BREAK
| SR_FRAME
|
156 SR_PARITY
| SR_OVERRUN
))) {
157 if (status
& SR_BREAK
) {
158 status
&= ~(SR_PARITY
| SR_FRAME
);
160 if (uart_handle_break(port
))
162 } else if (status
& SR_PARITY
)
163 port
->icount
.parity
++;
164 else if (status
& SR_FRAME
)
165 port
->icount
.frame
++;
166 if (status
& SR_OVERRUN
)
167 port
->icount
.overrun
++;
169 status
&= port
->read_status_mask
;
170 if (status
& SR_BREAK
)
172 else if (status
& SR_PARITY
)
174 else if (status
& SR_FRAME
)
178 if (uart_handle_sysrq_char(port
, ch
))
181 if (status
& port
->ignore_status_mask
)
184 tty_insert_flip_char(tty
, ch
, flag
);
189 static void transmit_chars(struct uart_port
*port
)
191 struct circ_buf
*xmit
;
196 xmit
= &port
->state
->xmit
;
197 if (uart_circ_empty(xmit
) || uart_tx_stopped(port
)) {
198 sc26xx_disable_irq(port
, IMR_TXRDY
);
201 while (!uart_circ_empty(xmit
)) {
202 if (!(READ_SC_PORT(port
, SR
) & SR_TXRDY
))
205 WRITE_SC_PORT(port
, THR
, xmit
->buf
[xmit
->tail
]);
206 xmit
->tail
= (xmit
->tail
+ 1) & (UART_XMIT_SIZE
- 1);
209 if (uart_circ_chars_pending(xmit
) < WAKEUP_CHARS
)
210 uart_write_wakeup(port
);
213 static irqreturn_t
sc26xx_interrupt(int irq
, void *dev_id
)
215 struct uart_sc26xx_port
*up
= dev_id
;
216 struct tty_struct
*tty
;
220 spin_lock_irqsave(&up
->port
[0].lock
, flags
);
223 isr
= READ_SC(&up
->port
[0], ISR
);
224 if (isr
& ISR_TXRDYA
)
225 transmit_chars(&up
->port
[0]);
226 if (isr
& ISR_RXRDYA
)
227 tty
= receive_chars(&up
->port
[0]);
229 spin_unlock(&up
->port
[0].lock
);
232 tty_flip_buffer_push(tty
);
234 spin_lock(&up
->port
[1].lock
);
237 if (isr
& ISR_TXRDYB
)
238 transmit_chars(&up
->port
[1]);
239 if (isr
& ISR_RXRDYB
)
240 tty
= receive_chars(&up
->port
[1]);
242 spin_unlock_irqrestore(&up
->port
[1].lock
, flags
);
245 tty_flip_buffer_push(tty
);
250 /* port->lock is not held. */
251 static unsigned int sc26xx_tx_empty(struct uart_port
*port
)
253 return (READ_SC_PORT(port
, SR
) & SR_TXRDY
) ? TIOCSER_TEMT
: 0;
256 /* port->lock held by caller. */
257 static void sc26xx_set_mctrl(struct uart_port
*port
, unsigned int mctrl
)
259 struct uart_sc26xx_port
*up
;
260 int line
= port
->line
;
263 up
= container_of(port
, struct uart_sc26xx_port
, port
[0]);
265 if (up
->dtr_mask
[line
]) {
266 if (mctrl
& TIOCM_DTR
)
267 WRITE_SC(port
, OPR_SET
, up
->dtr_mask
[line
]);
269 WRITE_SC(port
, OPR_CLR
, up
->dtr_mask
[line
]);
271 if (up
->rts_mask
[line
]) {
272 if (mctrl
& TIOCM_RTS
)
273 WRITE_SC(port
, OPR_SET
, up
->rts_mask
[line
]);
275 WRITE_SC(port
, OPR_CLR
, up
->rts_mask
[line
]);
279 /* port->lock is held by caller and interrupts are disabled. */
280 static unsigned int sc26xx_get_mctrl(struct uart_port
*port
)
282 struct uart_sc26xx_port
*up
;
283 int line
= port
->line
;
284 unsigned int mctrl
= TIOCM_DSR
| TIOCM_CTS
| TIOCM_CAR
;
288 up
= container_of(port
, struct uart_sc26xx_port
, port
[0]);
289 ipr
= READ_SC(port
, IPR
) ^ 0xff;
291 if (up
->dsr_mask
[line
]) {
293 mctrl
|= ipr
& up
->dsr_mask
[line
] ? TIOCM_DSR
: 0;
295 if (up
->cts_mask
[line
]) {
297 mctrl
|= ipr
& up
->cts_mask
[line
] ? TIOCM_CTS
: 0;
299 if (up
->dcd_mask
[line
]) {
301 mctrl
|= ipr
& up
->dcd_mask
[line
] ? TIOCM_CAR
: 0;
303 if (up
->ri_mask
[line
]) {
305 mctrl
|= ipr
& up
->ri_mask
[line
] ? TIOCM_RNG
: 0;
310 /* port->lock held by caller. */
311 static void sc26xx_stop_tx(struct uart_port
*port
)
316 /* port->lock held by caller. */
317 static void sc26xx_start_tx(struct uart_port
*port
)
319 struct circ_buf
*xmit
= &port
->state
->xmit
;
321 while (!uart_circ_empty(xmit
)) {
322 if (!(READ_SC_PORT(port
, SR
) & SR_TXRDY
)) {
323 sc26xx_enable_irq(port
, IMR_TXRDY
);
326 WRITE_SC_PORT(port
, THR
, xmit
->buf
[xmit
->tail
]);
327 xmit
->tail
= (xmit
->tail
+ 1) & (UART_XMIT_SIZE
- 1);
332 /* port->lock held by caller. */
333 static void sc26xx_stop_rx(struct uart_port
*port
)
337 /* port->lock held by caller. */
338 static void sc26xx_enable_ms(struct uart_port
*port
)
342 /* port->lock is not held. */
343 static void sc26xx_break_ctl(struct uart_port
*port
, int break_state
)
345 if (break_state
== -1)
346 WRITE_SC_PORT(port
, CR
, CR_STRT_BRK
);
348 WRITE_SC_PORT(port
, CR
, CR_STOP_BRK
);
351 /* port->lock is not held. */
352 static int sc26xx_startup(struct uart_port
*port
)
354 sc26xx_disable_irq(port
, IMR_TXRDY
| IMR_RXRDY
);
355 WRITE_SC(port
, OPCR
, 0);
357 /* reset tx and rx */
358 WRITE_SC_PORT(port
, CR
, CR_RES_RX
);
359 WRITE_SC_PORT(port
, CR
, CR_RES_TX
);
362 WRITE_SC_PORT(port
, CR
, CR_ENA_TX
| CR_ENA_RX
);
365 sc26xx_enable_irq(port
, IMR_RXRDY
);
369 /* port->lock is not held. */
370 static void sc26xx_shutdown(struct uart_port
*port
)
372 /* disable interrupst */
373 sc26xx_disable_irq(port
, IMR_TXRDY
| IMR_RXRDY
);
376 WRITE_SC_PORT(port
, CR
, CR_DIS_TX
| CR_DIS_RX
);
379 /* port->lock is not held. */
380 static void sc26xx_set_termios(struct uart_port
*port
, struct ktermios
*termios
,
381 struct ktermios
*old
)
383 unsigned int baud
= uart_get_baud_rate(port
, termios
, old
, 0, 4000000);
384 unsigned int quot
= uart_get_divisor(port
, baud
);
385 unsigned int iflag
, cflag
;
389 spin_lock_irqsave(&port
->lock
, flags
);
391 while ((READ_SC_PORT(port
, SR
) & ((1 << 3) | (1 << 2))) != 0xc)
394 WRITE_SC_PORT(port
, CR
, CR_DIS_TX
| CR_DIS_RX
);
396 iflag
= termios
->c_iflag
;
397 cflag
= termios
->c_cflag
;
399 port
->read_status_mask
= SR_OVERRUN
;
401 port
->read_status_mask
|= SR_PARITY
| SR_FRAME
;
402 if (iflag
& (BRKINT
| PARMRK
))
403 port
->read_status_mask
|= SR_BREAK
;
405 port
->ignore_status_mask
= 0;
407 port
->ignore_status_mask
|= SR_BREAK
;
408 if ((cflag
& CREAD
) == 0)
409 port
->ignore_status_mask
|= SR_BREAK
| SR_FRAME
|
410 SR_PARITY
| SR_OVERRUN
;
412 switch (cflag
& CSIZE
) {
430 if (cflag
& PARENB
) {
473 WRITE_SC_PORT(port
, CR
, CR_RES_MR
);
474 WRITE_SC_PORT(port
, MRx
, mr1
);
475 WRITE_SC_PORT(port
, MRx
, mr2
);
477 WRITE_SC(port
, ACR
, 0x80);
478 WRITE_SC_PORT(port
, CSR
, csr
);
480 /* reset tx and rx */
481 WRITE_SC_PORT(port
, CR
, CR_RES_RX
);
482 WRITE_SC_PORT(port
, CR
, CR_RES_TX
);
484 WRITE_SC_PORT(port
, CR
, CR_ENA_TX
| CR_ENA_RX
);
485 while ((READ_SC_PORT(port
, SR
) & ((1 << 3) | (1 << 2))) != 0xc)
489 uart_update_timeout(port
, cflag
,
490 (port
->uartclk
/ (16 * quot
)));
492 spin_unlock_irqrestore(&port
->lock
, flags
);
495 static const char *sc26xx_type(struct uart_port
*port
)
500 static void sc26xx_release_port(struct uart_port
*port
)
504 static int sc26xx_request_port(struct uart_port
*port
)
509 static void sc26xx_config_port(struct uart_port
*port
, int flags
)
513 static int sc26xx_verify_port(struct uart_port
*port
, struct serial_struct
*ser
)
518 static struct uart_ops sc26xx_ops
= {
519 .tx_empty
= sc26xx_tx_empty
,
520 .set_mctrl
= sc26xx_set_mctrl
,
521 .get_mctrl
= sc26xx_get_mctrl
,
522 .stop_tx
= sc26xx_stop_tx
,
523 .start_tx
= sc26xx_start_tx
,
524 .stop_rx
= sc26xx_stop_rx
,
525 .enable_ms
= sc26xx_enable_ms
,
526 .break_ctl
= sc26xx_break_ctl
,
527 .startup
= sc26xx_startup
,
528 .shutdown
= sc26xx_shutdown
,
529 .set_termios
= sc26xx_set_termios
,
531 .release_port
= sc26xx_release_port
,
532 .request_port
= sc26xx_request_port
,
533 .config_port
= sc26xx_config_port
,
534 .verify_port
= sc26xx_verify_port
,
537 static struct uart_port
*sc26xx_port
;
539 #ifdef CONFIG_SERIAL_SC26XX_CONSOLE
540 static void sc26xx_console_putchar(struct uart_port
*port
, char c
)
545 spin_lock_irqsave(&port
->lock
, flags
);
547 while (limit
-- > 0) {
548 if (READ_SC_PORT(port
, SR
) & SR_TXRDY
) {
549 WRITE_SC_PORT(port
, THR
, c
);
555 spin_unlock_irqrestore(&port
->lock
, flags
);
558 static void sc26xx_console_write(struct console
*con
, const char *s
, unsigned n
)
560 struct uart_port
*port
= sc26xx_port
;
563 for (i
= 0; i
< n
; i
++) {
565 sc26xx_console_putchar(port
, '\r');
566 sc26xx_console_putchar(port
, *s
++);
570 static int __init
sc26xx_console_setup(struct console
*con
, char *options
)
572 struct uart_port
*port
= sc26xx_port
;
578 if (port
->type
!= PORT_SC26XX
)
581 printk(KERN_INFO
"Console: ttySC%d (SC26XX)\n", con
->index
);
583 uart_parse_options(options
, &baud
, &parity
, &bits
, &flow
);
585 return uart_set_options(port
, con
, baud
, parity
, bits
, flow
);
588 static struct uart_driver sc26xx_reg
;
589 static struct console sc26xx_console
= {
591 .write
= sc26xx_console_write
,
592 .device
= uart_console_device
,
593 .setup
= sc26xx_console_setup
,
594 .flags
= CON_PRINTBUFFER
,
598 #define SC26XX_CONSOLE &sc26xx_console
600 #define SC26XX_CONSOLE NULL
603 static struct uart_driver sc26xx_reg
= {
604 .owner
= THIS_MODULE
,
605 .driver_name
= "SC26xx",
607 .major
= SC26XX_MAJOR
,
608 .minor
= SC26XX_MINOR_START
,
610 .cons
= SC26XX_CONSOLE
,
613 static u8
sc26xx_flags2mask(unsigned int flags
, unsigned int bitpos
)
615 unsigned int bit
= (flags
>> bitpos
) & 15;
617 return bit
? (1 << (bit
- 1)) : 0;
620 static void __devinit
sc26xx_init_masks(struct uart_sc26xx_port
*up
,
621 int line
, unsigned int data
)
623 up
->dtr_mask
[line
] = sc26xx_flags2mask(data
, 0);
624 up
->rts_mask
[line
] = sc26xx_flags2mask(data
, 4);
625 up
->dsr_mask
[line
] = sc26xx_flags2mask(data
, 8);
626 up
->cts_mask
[line
] = sc26xx_flags2mask(data
, 12);
627 up
->dcd_mask
[line
] = sc26xx_flags2mask(data
, 16);
628 up
->ri_mask
[line
] = sc26xx_flags2mask(data
, 20);
631 static int __devinit
sc26xx_probe(struct platform_device
*dev
)
633 struct resource
*res
;
634 struct uart_sc26xx_port
*up
;
635 unsigned int *sc26xx_data
= dev
->dev
.platform_data
;
638 res
= platform_get_resource(dev
, IORESOURCE_MEM
, 0);
642 up
= kzalloc(sizeof *up
, GFP_KERNEL
);
646 up
->port
[0].line
= 0;
647 up
->port
[0].ops
= &sc26xx_ops
;
648 up
->port
[0].type
= PORT_SC26XX
;
649 up
->port
[0].uartclk
= (29491200 / 16); /* arbitrary */
651 up
->port
[0].mapbase
= res
->start
;
652 up
->port
[0].membase
= ioremap_nocache(up
->port
[0].mapbase
, 0x40);
653 up
->port
[0].iotype
= UPIO_MEM
;
654 up
->port
[0].irq
= platform_get_irq(dev
, 0);
656 up
->port
[0].dev
= &dev
->dev
;
658 sc26xx_init_masks(up
, 0, sc26xx_data
[0]);
660 sc26xx_port
= &up
->port
[0];
662 up
->port
[1].line
= 1;
663 up
->port
[1].ops
= &sc26xx_ops
;
664 up
->port
[1].type
= PORT_SC26XX
;
665 up
->port
[1].uartclk
= (29491200 / 16); /* arbitrary */
667 up
->port
[1].mapbase
= up
->port
[0].mapbase
;
668 up
->port
[1].membase
= up
->port
[0].membase
;
669 up
->port
[1].iotype
= UPIO_MEM
;
670 up
->port
[1].irq
= up
->port
[0].irq
;
672 up
->port
[1].dev
= &dev
->dev
;
674 sc26xx_init_masks(up
, 1, sc26xx_data
[1]);
676 err
= uart_register_driver(&sc26xx_reg
);
680 sc26xx_reg
.tty_driver
->name_base
= sc26xx_reg
.minor
;
682 err
= uart_add_one_port(&sc26xx_reg
, &up
->port
[0]);
684 goto out_unregister_driver
;
686 err
= uart_add_one_port(&sc26xx_reg
, &up
->port
[1]);
688 goto out_remove_port0
;
690 err
= request_irq(up
->port
[0].irq
, sc26xx_interrupt
, 0, "sc26xx", up
);
692 goto out_remove_ports
;
694 dev_set_drvdata(&dev
->dev
, up
);
698 uart_remove_one_port(&sc26xx_reg
, &up
->port
[1]);
700 uart_remove_one_port(&sc26xx_reg
, &up
->port
[0]);
702 out_unregister_driver
:
703 uart_unregister_driver(&sc26xx_reg
);
712 static int __exit
sc26xx_driver_remove(struct platform_device
*dev
)
714 struct uart_sc26xx_port
*up
= dev_get_drvdata(&dev
->dev
);
716 free_irq(up
->port
[0].irq
, up
);
718 uart_remove_one_port(&sc26xx_reg
, &up
->port
[0]);
719 uart_remove_one_port(&sc26xx_reg
, &up
->port
[1]);
721 uart_unregister_driver(&sc26xx_reg
);
726 dev_set_drvdata(&dev
->dev
, NULL
);
730 static struct platform_driver sc26xx_driver
= {
731 .probe
= sc26xx_probe
,
732 .remove
= __devexit_p(sc26xx_driver_remove
),
735 .owner
= THIS_MODULE
,
739 module_platform_driver(sc26xx_driver
);
741 MODULE_AUTHOR("Thomas Bogendörfer");
742 MODULE_DESCRIPTION("SC681/SC2692 serial driver");
743 MODULE_VERSION("1.0");
744 MODULE_LICENSE("GPL");
745 MODULE_ALIAS("platform:SC26xx");