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>
25 #warning "Please try migrate to use new driver SCCNXP and report the status" \
26 "in the linux-serial mailing list."
28 #if defined(CONFIG_MAGIC_SYSRQ)
32 #include <linux/serial_core.h>
34 #define SC26XX_MAJOR 204
35 #define SC26XX_MINOR_START 205
38 struct uart_sc26xx_port {
39 struct uart_port port[2];
49 /* register common to both ports */
56 #define WR_OPR_SET 0x38
57 #define WR_OPR_CLR 0x3C
59 /* access common register */
60 #define READ_SC(p, r) readb((p)->membase + RD_##r)
61 #define WRITE_SC(p, r, v) writeb((v), (p)->membase + WR_##r)
63 /* register per port */
64 #define RD_PORT_MRx 0x00
65 #define RD_PORT_SR 0x04
66 #define RD_PORT_RHR 0x0c
68 #define WR_PORT_MRx 0x00
69 #define WR_PORT_CSR 0x04
70 #define WR_PORT_CR 0x08
71 #define WR_PORT_THR 0x0c
74 #define SR_BREAK (1 << 7)
75 #define SR_FRAME (1 << 6)
76 #define SR_PARITY (1 << 5)
77 #define SR_OVERRUN (1 << 4)
78 #define SR_TXRDY (1 << 2)
79 #define SR_RXRDY (1 << 0)
81 #define CR_RES_MR (1 << 4)
82 #define CR_RES_RX (2 << 4)
83 #define CR_RES_TX (3 << 4)
84 #define CR_STRT_BRK (6 << 4)
85 #define CR_STOP_BRK (7 << 4)
86 #define CR_DIS_TX (1 << 3)
87 #define CR_ENA_TX (1 << 2)
88 #define CR_DIS_RX (1 << 1)
89 #define CR_ENA_RX (1 << 0)
92 #define ISR_RXRDYB (1 << 5)
93 #define ISR_TXRDYB (1 << 4)
94 #define ISR_RXRDYA (1 << 1)
95 #define ISR_TXRDYA (1 << 0)
98 #define IMR_RXRDY (1 << 1)
99 #define IMR_TXRDY (1 << 0)
101 /* access port register */
102 static inline u8 read_sc_port(struct uart_port *p, u8 reg)
104 return readb(p->membase + p->line * 0x20 + reg);
107 static inline void write_sc_port(struct uart_port *p, u8 reg, u8 val)
109 writeb(val, p->membase + p->line * 0x20 + reg);
112 #define READ_SC_PORT(p, r) read_sc_port(p, RD_PORT_##r)
113 #define WRITE_SC_PORT(p, r, v) write_sc_port(p, WR_PORT_##r, v)
115 static void sc26xx_enable_irq(struct uart_port *port, int mask)
117 struct uart_sc26xx_port *up;
118 int line = port->line;
121 up = container_of(port, struct uart_sc26xx_port, port[0]);
123 up->imr |= mask << (line * 4);
124 WRITE_SC(port, IMR, up->imr);
127 static void sc26xx_disable_irq(struct uart_port *port, int mask)
129 struct uart_sc26xx_port *up;
130 int line = port->line;
133 up = container_of(port, struct uart_sc26xx_port, port[0]);
135 up->imr &= ~(mask << (line * 4));
136 WRITE_SC(port, IMR, up->imr);
139 static bool receive_chars(struct uart_port *port)
141 struct tty_port *tport = NULL;
147 /* FIXME what is this trying to achieve? */
148 if (port->state != NULL) /* Unopened serial console */
149 tport = &port->state->port;
151 while (limit-- > 0) {
152 status = READ_SC_PORT(port, SR);
153 if (!(status & SR_RXRDY))
155 ch = READ_SC_PORT(port, RHR);
160 if (unlikely(status & (SR_BREAK | SR_FRAME |
161 SR_PARITY | SR_OVERRUN))) {
162 if (status & SR_BREAK) {
163 status &= ~(SR_PARITY | SR_FRAME);
165 if (uart_handle_break(port))
167 } else if (status & SR_PARITY)
168 port->icount.parity++;
169 else if (status & SR_FRAME)
170 port->icount.frame++;
171 if (status & SR_OVERRUN)
172 port->icount.overrun++;
174 status &= port->read_status_mask;
175 if (status & SR_BREAK)
177 else if (status & SR_PARITY)
179 else if (status & SR_FRAME)
183 if (uart_handle_sysrq_char(port, ch))
186 if (status & port->ignore_status_mask)
189 tty_insert_flip_char(tport, ch, flag);
194 static void transmit_chars(struct uart_port *port)
196 struct circ_buf *xmit;
201 xmit = &port->state->xmit;
202 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
203 sc26xx_disable_irq(port, IMR_TXRDY);
206 while (!uart_circ_empty(xmit)) {
207 if (!(READ_SC_PORT(port, SR) & SR_TXRDY))
210 WRITE_SC_PORT(port, THR, xmit->buf[xmit->tail]);
211 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
214 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
215 uart_write_wakeup(port);
218 static irqreturn_t sc26xx_interrupt(int irq, void *dev_id)
220 struct uart_sc26xx_port *up = dev_id;
225 spin_lock_irqsave(&up->port[0].lock, flags);
228 isr = READ_SC(&up->port[0], ISR);
229 if (isr & ISR_TXRDYA)
230 transmit_chars(&up->port[0]);
231 if (isr & ISR_RXRDYA)
232 push = receive_chars(&up->port[0]);
234 spin_unlock(&up->port[0].lock);
237 tty_flip_buffer_push(&up->port[0].state->port);
239 spin_lock(&up->port[1].lock);
242 if (isr & ISR_TXRDYB)
243 transmit_chars(&up->port[1]);
244 if (isr & ISR_RXRDYB)
245 push = receive_chars(&up->port[1]);
247 spin_unlock_irqrestore(&up->port[1].lock, flags);
250 tty_flip_buffer_push(&up->port[1].state->port);
255 /* port->lock is not held. */
256 static unsigned int sc26xx_tx_empty(struct uart_port *port)
258 return (READ_SC_PORT(port, SR) & SR_TXRDY) ? TIOCSER_TEMT : 0;
261 /* port->lock held by caller. */
262 static void sc26xx_set_mctrl(struct uart_port *port, unsigned int mctrl)
264 struct uart_sc26xx_port *up;
265 int line = port->line;
268 up = container_of(port, struct uart_sc26xx_port, port[0]);
270 if (up->dtr_mask[line]) {
271 if (mctrl & TIOCM_DTR)
272 WRITE_SC(port, OPR_SET, up->dtr_mask[line]);
274 WRITE_SC(port, OPR_CLR, up->dtr_mask[line]);
276 if (up->rts_mask[line]) {
277 if (mctrl & TIOCM_RTS)
278 WRITE_SC(port, OPR_SET, up->rts_mask[line]);
280 WRITE_SC(port, OPR_CLR, up->rts_mask[line]);
284 /* port->lock is held by caller and interrupts are disabled. */
285 static unsigned int sc26xx_get_mctrl(struct uart_port *port)
287 struct uart_sc26xx_port *up;
288 int line = port->line;
289 unsigned int mctrl = TIOCM_DSR | TIOCM_CTS | TIOCM_CAR;
293 up = container_of(port, struct uart_sc26xx_port, port[0]);
294 ipr = READ_SC(port, IPR) ^ 0xff;
296 if (up->dsr_mask[line]) {
298 mctrl |= ipr & up->dsr_mask[line] ? TIOCM_DSR : 0;
300 if (up->cts_mask[line]) {
302 mctrl |= ipr & up->cts_mask[line] ? TIOCM_CTS : 0;
304 if (up->dcd_mask[line]) {
306 mctrl |= ipr & up->dcd_mask[line] ? TIOCM_CAR : 0;
308 if (up->ri_mask[line]) {
310 mctrl |= ipr & up->ri_mask[line] ? TIOCM_RNG : 0;
315 /* port->lock held by caller. */
316 static void sc26xx_stop_tx(struct uart_port *port)
321 /* port->lock held by caller. */
322 static void sc26xx_start_tx(struct uart_port *port)
324 struct circ_buf *xmit = &port->state->xmit;
326 while (!uart_circ_empty(xmit)) {
327 if (!(READ_SC_PORT(port, SR) & SR_TXRDY)) {
328 sc26xx_enable_irq(port, IMR_TXRDY);
331 WRITE_SC_PORT(port, THR, xmit->buf[xmit->tail]);
332 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
337 /* port->lock held by caller. */
338 static void sc26xx_stop_rx(struct uart_port *port)
342 /* port->lock held by caller. */
343 static void sc26xx_enable_ms(struct uart_port *port)
347 /* port->lock is not held. */
348 static void sc26xx_break_ctl(struct uart_port *port, int break_state)
350 if (break_state == -1)
351 WRITE_SC_PORT(port, CR, CR_STRT_BRK);
353 WRITE_SC_PORT(port, CR, CR_STOP_BRK);
356 /* port->lock is not held. */
357 static int sc26xx_startup(struct uart_port *port)
359 sc26xx_disable_irq(port, IMR_TXRDY | IMR_RXRDY);
360 WRITE_SC(port, OPCR, 0);
362 /* reset tx and rx */
363 WRITE_SC_PORT(port, CR, CR_RES_RX);
364 WRITE_SC_PORT(port, CR, CR_RES_TX);
367 WRITE_SC_PORT(port, CR, CR_ENA_TX | CR_ENA_RX);
370 sc26xx_enable_irq(port, IMR_RXRDY);
374 /* port->lock is not held. */
375 static void sc26xx_shutdown(struct uart_port *port)
377 /* disable interrupst */
378 sc26xx_disable_irq(port, IMR_TXRDY | IMR_RXRDY);
381 WRITE_SC_PORT(port, CR, CR_DIS_TX | CR_DIS_RX);
384 /* port->lock is not held. */
385 static void sc26xx_set_termios(struct uart_port *port, struct ktermios *termios,
386 struct ktermios *old)
388 unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
389 unsigned int quot = uart_get_divisor(port, baud);
390 unsigned int iflag, cflag;
394 spin_lock_irqsave(&port->lock, flags);
396 while ((READ_SC_PORT(port, SR) & ((1 << 3) | (1 << 2))) != 0xc)
399 WRITE_SC_PORT(port, CR, CR_DIS_TX | CR_DIS_RX);
401 iflag = termios->c_iflag;
402 cflag = termios->c_cflag;
404 port->read_status_mask = SR_OVERRUN;
406 port->read_status_mask |= SR_PARITY | SR_FRAME;
407 if (iflag & (BRKINT | PARMRK))
408 port->read_status_mask |= SR_BREAK;
410 port->ignore_status_mask = 0;
412 port->ignore_status_mask |= SR_BREAK;
413 if ((cflag & CREAD) == 0)
414 port->ignore_status_mask |= SR_BREAK | SR_FRAME |
415 SR_PARITY | SR_OVERRUN;
417 switch (cflag & CSIZE) {
435 if (cflag & PARENB) {
478 WRITE_SC_PORT(port, CR, CR_RES_MR);
479 WRITE_SC_PORT(port, MRx, mr1);
480 WRITE_SC_PORT(port, MRx, mr2);
482 WRITE_SC(port, ACR, 0x80);
483 WRITE_SC_PORT(port, CSR, csr);
485 /* reset tx and rx */
486 WRITE_SC_PORT(port, CR, CR_RES_RX);
487 WRITE_SC_PORT(port, CR, CR_RES_TX);
489 WRITE_SC_PORT(port, CR, CR_ENA_TX | CR_ENA_RX);
490 while ((READ_SC_PORT(port, SR) & ((1 << 3) | (1 << 2))) != 0xc)
494 uart_update_timeout(port, cflag,
495 (port->uartclk / (16 * quot)));
497 spin_unlock_irqrestore(&port->lock, flags);
500 static const char *sc26xx_type(struct uart_port *port)
505 static void sc26xx_release_port(struct uart_port *port)
509 static int sc26xx_request_port(struct uart_port *port)
514 static void sc26xx_config_port(struct uart_port *port, int flags)
518 static int sc26xx_verify_port(struct uart_port *port, struct serial_struct *ser)
523 static struct uart_ops sc26xx_ops = {
524 .tx_empty = sc26xx_tx_empty,
525 .set_mctrl = sc26xx_set_mctrl,
526 .get_mctrl = sc26xx_get_mctrl,
527 .stop_tx = sc26xx_stop_tx,
528 .start_tx = sc26xx_start_tx,
529 .stop_rx = sc26xx_stop_rx,
530 .enable_ms = sc26xx_enable_ms,
531 .break_ctl = sc26xx_break_ctl,
532 .startup = sc26xx_startup,
533 .shutdown = sc26xx_shutdown,
534 .set_termios = sc26xx_set_termios,
536 .release_port = sc26xx_release_port,
537 .request_port = sc26xx_request_port,
538 .config_port = sc26xx_config_port,
539 .verify_port = sc26xx_verify_port,
542 static struct uart_port *sc26xx_port;
544 #ifdef CONFIG_SERIAL_SC26XX_CONSOLE
545 static void sc26xx_console_putchar(struct uart_port *port, char c)
550 spin_lock_irqsave(&port->lock, flags);
552 while (limit-- > 0) {
553 if (READ_SC_PORT(port, SR) & SR_TXRDY) {
554 WRITE_SC_PORT(port, THR, c);
560 spin_unlock_irqrestore(&port->lock, flags);
563 static void sc26xx_console_write(struct console *con, const char *s, unsigned n)
565 struct uart_port *port = sc26xx_port;
568 for (i = 0; i < n; i++) {
570 sc26xx_console_putchar(port, '\r');
571 sc26xx_console_putchar(port, *s++);
575 static int __init sc26xx_console_setup(struct console *con, char *options)
577 struct uart_port *port = sc26xx_port;
583 if (port->type != PORT_SC26XX)
586 printk(KERN_INFO "Console: ttySC%d (SC26XX)\n", con->index);
588 uart_parse_options(options, &baud, &parity, &bits, &flow);
590 return uart_set_options(port, con, baud, parity, bits, flow);
593 static struct uart_driver sc26xx_reg;
594 static struct console sc26xx_console = {
596 .write = sc26xx_console_write,
597 .device = uart_console_device,
598 .setup = sc26xx_console_setup,
599 .flags = CON_PRINTBUFFER,
603 #define SC26XX_CONSOLE &sc26xx_console
605 #define SC26XX_CONSOLE NULL
608 static struct uart_driver sc26xx_reg = {
609 .owner = THIS_MODULE,
610 .driver_name = "SC26xx",
612 .major = SC26XX_MAJOR,
613 .minor = SC26XX_MINOR_START,
615 .cons = SC26XX_CONSOLE,
618 static u8 sc26xx_flags2mask(unsigned int flags, unsigned int bitpos)
620 unsigned int bit = (flags >> bitpos) & 15;
622 return bit ? (1 << (bit - 1)) : 0;
625 static void sc26xx_init_masks(struct uart_sc26xx_port *up,
626 int line, unsigned int data)
628 up->dtr_mask[line] = sc26xx_flags2mask(data, 0);
629 up->rts_mask[line] = sc26xx_flags2mask(data, 4);
630 up->dsr_mask[line] = sc26xx_flags2mask(data, 8);
631 up->cts_mask[line] = sc26xx_flags2mask(data, 12);
632 up->dcd_mask[line] = sc26xx_flags2mask(data, 16);
633 up->ri_mask[line] = sc26xx_flags2mask(data, 20);
636 static int sc26xx_probe(struct platform_device *dev)
638 struct resource *res;
639 struct uart_sc26xx_port *up;
640 unsigned int *sc26xx_data = dev->dev.platform_data;
643 res = platform_get_resource(dev, IORESOURCE_MEM, 0);
647 up = kzalloc(sizeof *up, GFP_KERNEL);
651 up->port[0].line = 0;
652 up->port[0].ops = &sc26xx_ops;
653 up->port[0].type = PORT_SC26XX;
654 up->port[0].uartclk = (29491200 / 16); /* arbitrary */
656 up->port[0].mapbase = res->start;
657 up->port[0].membase = ioremap_nocache(up->port[0].mapbase, 0x40);
658 up->port[0].iotype = UPIO_MEM;
659 up->port[0].irq = platform_get_irq(dev, 0);
661 up->port[0].dev = &dev->dev;
663 sc26xx_init_masks(up, 0, sc26xx_data[0]);
665 sc26xx_port = &up->port[0];
667 up->port[1].line = 1;
668 up->port[1].ops = &sc26xx_ops;
669 up->port[1].type = PORT_SC26XX;
670 up->port[1].uartclk = (29491200 / 16); /* arbitrary */
672 up->port[1].mapbase = up->port[0].mapbase;
673 up->port[1].membase = up->port[0].membase;
674 up->port[1].iotype = UPIO_MEM;
675 up->port[1].irq = up->port[0].irq;
677 up->port[1].dev = &dev->dev;
679 sc26xx_init_masks(up, 1, sc26xx_data[1]);
681 err = uart_register_driver(&sc26xx_reg);
685 sc26xx_reg.tty_driver->name_base = sc26xx_reg.minor;
687 err = uart_add_one_port(&sc26xx_reg, &up->port[0]);
689 goto out_unregister_driver;
691 err = uart_add_one_port(&sc26xx_reg, &up->port[1]);
693 goto out_remove_port0;
695 err = request_irq(up->port[0].irq, sc26xx_interrupt, 0, "sc26xx", up);
697 goto out_remove_ports;
699 dev_set_drvdata(&dev->dev, up);
703 uart_remove_one_port(&sc26xx_reg, &up->port[1]);
705 uart_remove_one_port(&sc26xx_reg, &up->port[0]);
707 out_unregister_driver:
708 uart_unregister_driver(&sc26xx_reg);
717 static int __exit sc26xx_driver_remove(struct platform_device *dev)
719 struct uart_sc26xx_port *up = dev_get_drvdata(&dev->dev);
721 free_irq(up->port[0].irq, up);
723 uart_remove_one_port(&sc26xx_reg, &up->port[0]);
724 uart_remove_one_port(&sc26xx_reg, &up->port[1]);
726 uart_unregister_driver(&sc26xx_reg);
731 dev_set_drvdata(&dev->dev, NULL);
735 static struct platform_driver sc26xx_driver = {
736 .probe = sc26xx_probe,
737 .remove = sc26xx_driver_remove,
740 .owner = THIS_MODULE,
744 module_platform_driver(sc26xx_driver);
746 MODULE_AUTHOR("Thomas Bogendörfer");
747 MODULE_DESCRIPTION("SC681/SC2692 serial driver");
748 MODULE_VERSION("1.0");
749 MODULE_LICENSE("GPL");
750 MODULE_ALIAS("platform:SC26xx");