2 * Driver for CLPS711x serial ports
4 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
6 * Copyright 1999 ARM Limited
7 * Copyright (C) 2000 Deep Blue Solutions Ltd.
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 #if defined(CONFIG_SERIAL_CLPS711X_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
28 #include <linux/module.h>
29 #include <linux/ioport.h>
30 #include <linux/init.h>
31 #include <linux/console.h>
32 #include <linux/sysrq.h>
33 #include <linux/spinlock.h>
34 #include <linux/device.h>
35 #include <linux/tty.h>
36 #include <linux/tty_flip.h>
37 #include <linux/serial_core.h>
38 #include <linux/serial.h>
40 #include <linux/platform_device.h>
42 #include <mach/hardware.h>
45 #define UART_CLPS711X_NAME "uart-clps711x"
46 #define UART_CLPS711X_NR 2
47 #define UART_CLPS711X_MAJOR 204
48 #define UART_CLPS711X_MINOR 40
50 #define UBRLCR(port) ((port)->line ? UBRLCR2 : UBRLCR1)
51 #define UARTDR(port) ((port)->line ? UARTDR2 : UARTDR1)
52 #define SYSFLG(port) ((port)->line ? SYSFLG2 : SYSFLG1)
53 #define SYSCON(port) ((port)->line ? SYSCON2 : SYSCON1)
54 #define TX_IRQ(port) ((port)->line ? IRQ_UTXINT2 : IRQ_UTXINT1)
55 #define RX_IRQ(port) ((port)->line ? IRQ_URXINT2 : IRQ_URXINT1)
57 #define UART_ANY_ERR (UARTDR_FRMERR | UARTDR_PARERR | UARTDR_OVERR)
59 #define tx_enabled(port) ((port)->unused[0])
61 struct clps711x_port {
62 struct uart_driver uart;
63 struct uart_port port[UART_CLPS711X_NR];
64 #ifdef CONFIG_SERIAL_CLPS711X_CONSOLE
65 struct console console;
69 static void clps711xuart_stop_tx(struct uart_port *port)
71 if (tx_enabled(port)) {
72 disable_irq(TX_IRQ(port));
77 static void clps711xuart_start_tx(struct uart_port *port)
79 if (!tx_enabled(port)) {
80 enable_irq(TX_IRQ(port));
85 static void clps711xuart_stop_rx(struct uart_port *port)
87 disable_irq(RX_IRQ(port));
90 static void clps711xuart_enable_ms(struct uart_port *port)
94 static irqreturn_t clps711xuart_int_rx(int irq, void *dev_id)
96 struct uart_port *port = dev_id;
97 struct tty_struct *tty = port->state->port.tty;
98 unsigned int status, ch, flg;
100 status = clps_readl(SYSFLG(port));
101 while (!(status & SYSFLG_URXFE)) {
102 ch = clps_readl(UARTDR(port));
109 * Note that the error handling code is
110 * out of the main execution path
112 if (unlikely(ch & UART_ANY_ERR)) {
113 if (ch & UARTDR_PARERR)
114 port->icount.parity++;
115 else if (ch & UARTDR_FRMERR)
116 port->icount.frame++;
117 if (ch & UARTDR_OVERR)
118 port->icount.overrun++;
120 ch &= port->read_status_mask;
122 if (ch & UARTDR_PARERR)
124 else if (ch & UARTDR_FRMERR)
132 if (uart_handle_sysrq_char(port, ch))
136 * CHECK: does overrun affect the current character?
137 * ASSUMPTION: it does not.
139 uart_insert_char(port, ch, UARTDR_OVERR, ch, flg);
142 status = clps_readl(SYSFLG(port));
144 tty_flip_buffer_push(tty);
148 static irqreturn_t clps711xuart_int_tx(int irq, void *dev_id)
150 struct uart_port *port = dev_id;
151 struct circ_buf *xmit = &port->state->xmit;
155 clps_writel(port->x_char, UARTDR(port));
161 if (uart_circ_empty(xmit) || uart_tx_stopped(port))
164 count = port->fifosize >> 1;
166 clps_writel(xmit->buf[xmit->tail], UARTDR(port));
167 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
169 if (uart_circ_empty(xmit))
171 } while (--count > 0);
173 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
174 uart_write_wakeup(port);
176 if (uart_circ_empty(xmit)) {
178 disable_irq_nosync(TX_IRQ(port));
179 tx_enabled(port) = 0;
185 static unsigned int clps711xuart_tx_empty(struct uart_port *port)
187 unsigned int status = clps_readl(SYSFLG(port));
188 return status & SYSFLG_UBUSY ? 0 : TIOCSER_TEMT;
191 static unsigned int clps711xuart_get_mctrl(struct uart_port *port)
193 unsigned int port_addr;
194 unsigned int result = 0;
197 port_addr = SYSFLG(port);
198 if (port_addr == SYSFLG1) {
199 status = clps_readl(SYSFLG1);
200 if (status & SYSFLG1_DCD)
202 if (status & SYSFLG1_DSR)
204 if (status & SYSFLG1_CTS)
212 clps711xuart_set_mctrl_null(struct uart_port *port, unsigned int mctrl)
216 static void clps711xuart_break_ctl(struct uart_port *port, int break_state)
221 spin_lock_irqsave(&port->lock, flags);
222 ubrlcr = clps_readl(UBRLCR(port));
223 if (break_state == -1)
224 ubrlcr |= UBRLCR_BREAK;
226 ubrlcr &= ~UBRLCR_BREAK;
227 clps_writel(ubrlcr, UBRLCR(port));
228 spin_unlock_irqrestore(&port->lock, flags);
231 static int clps711xuart_startup(struct uart_port *port)
236 tx_enabled(port) = 1;
241 retval = request_irq(TX_IRQ(port), clps711xuart_int_tx, 0,
242 "clps711xuart_tx", port);
246 retval = request_irq(RX_IRQ(port), clps711xuart_int_rx, 0,
247 "clps711xuart_rx", port);
249 free_irq(TX_IRQ(port), port);
256 syscon = clps_readl(SYSCON(port));
257 syscon |= SYSCON_UARTEN;
258 clps_writel(syscon, SYSCON(port));
263 static void clps711xuart_shutdown(struct uart_port *port)
265 unsigned int ubrlcr, syscon;
270 free_irq(TX_IRQ(port), port); /* TX interrupt */
271 free_irq(RX_IRQ(port), port); /* RX interrupt */
276 syscon = clps_readl(SYSCON(port));
277 syscon &= ~SYSCON_UARTEN;
278 clps_writel(syscon, SYSCON(port));
281 * disable break condition and fifos
283 ubrlcr = clps_readl(UBRLCR(port));
284 ubrlcr &= ~(UBRLCR_FIFOEN | UBRLCR_BREAK);
285 clps_writel(ubrlcr, UBRLCR(port));
289 clps711xuart_set_termios(struct uart_port *port, struct ktermios *termios,
290 struct ktermios *old)
292 unsigned int ubrlcr, baud, quot;
296 * We don't implement CREAD.
298 termios->c_cflag |= CREAD;
301 * Ask the core to calculate the divisor for us.
303 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
304 quot = uart_get_divisor(port, baud);
306 switch (termios->c_cflag & CSIZE) {
308 ubrlcr = UBRLCR_WRDLEN5;
311 ubrlcr = UBRLCR_WRDLEN6;
314 ubrlcr = UBRLCR_WRDLEN7;
317 ubrlcr = UBRLCR_WRDLEN8;
320 if (termios->c_cflag & CSTOPB)
321 ubrlcr |= UBRLCR_XSTOP;
322 if (termios->c_cflag & PARENB) {
323 ubrlcr |= UBRLCR_PRTEN;
324 if (!(termios->c_cflag & PARODD))
325 ubrlcr |= UBRLCR_EVENPRT;
327 if (port->fifosize > 1)
328 ubrlcr |= UBRLCR_FIFOEN;
330 spin_lock_irqsave(&port->lock, flags);
333 * Update the per-port timeout.
335 uart_update_timeout(port, termios->c_cflag, baud);
337 port->read_status_mask = UARTDR_OVERR;
338 if (termios->c_iflag & INPCK)
339 port->read_status_mask |= UARTDR_PARERR | UARTDR_FRMERR;
342 * Characters to ignore
344 port->ignore_status_mask = 0;
345 if (termios->c_iflag & IGNPAR)
346 port->ignore_status_mask |= UARTDR_FRMERR | UARTDR_PARERR;
347 if (termios->c_iflag & IGNBRK) {
349 * If we're ignoring parity and break indicators,
350 * ignore overruns to (for real raw support).
352 if (termios->c_iflag & IGNPAR)
353 port->ignore_status_mask |= UARTDR_OVERR;
358 clps_writel(ubrlcr | quot, UBRLCR(port));
360 spin_unlock_irqrestore(&port->lock, flags);
363 static const char *clps711xuart_type(struct uart_port *port)
365 return port->type == PORT_CLPS711X ? "CLPS711x" : NULL;
369 * Configure/autoconfigure the port.
371 static void clps711xuart_config_port(struct uart_port *port, int flags)
373 if (flags & UART_CONFIG_TYPE)
374 port->type = PORT_CLPS711X;
377 static void clps711xuart_release_port(struct uart_port *port)
381 static int clps711xuart_request_port(struct uart_port *port)
386 static struct uart_ops uart_clps711x_ops = {
387 .tx_empty = clps711xuart_tx_empty,
388 .set_mctrl = clps711xuart_set_mctrl_null,
389 .get_mctrl = clps711xuart_get_mctrl,
390 .stop_tx = clps711xuart_stop_tx,
391 .start_tx = clps711xuart_start_tx,
392 .stop_rx = clps711xuart_stop_rx,
393 .enable_ms = clps711xuart_enable_ms,
394 .break_ctl = clps711xuart_break_ctl,
395 .startup = clps711xuart_startup,
396 .shutdown = clps711xuart_shutdown,
397 .set_termios = clps711xuart_set_termios,
398 .type = clps711xuart_type,
399 .config_port = clps711xuart_config_port,
400 .release_port = clps711xuart_release_port,
401 .request_port = clps711xuart_request_port,
404 #ifdef CONFIG_SERIAL_CLPS711X_CONSOLE
405 static void uart_clps711x_console_putchar(struct uart_port *port, int ch)
407 while (clps_readl(SYSFLG(port)) & SYSFLG_UTXFF)
410 clps_writew(ch, UARTDR(port));
413 static void uart_clps711x_console_write(struct console *co, const char *c,
416 struct clps711x_port *s = (struct clps711x_port *)co->data;
417 struct uart_port *port = &s->port[co->index];
420 /* Ensure that the port is enabled */
421 syscon = clps_readl(SYSCON(port));
422 clps_writel(syscon | SYSCON_UARTEN, SYSCON(port));
424 uart_console_write(port, c, n, uart_clps711x_console_putchar);
426 /* Wait for transmitter to become empty */
427 while (clps_readl(SYSFLG(port)) & SYSFLG_UBUSY)
430 /* Restore the uart state */
431 clps_writel(syscon, SYSCON(port));
434 static void uart_clps711x_console_get_options(struct uart_port *port,
435 int *baud, int *parity,
438 if (clps_readl(SYSCON(port)) & SYSCON_UARTEN) {
439 unsigned int ubrlcr, quot;
441 ubrlcr = clps_readl(UBRLCR(port));
444 if (ubrlcr & UBRLCR_PRTEN) {
445 if (ubrlcr & UBRLCR_EVENPRT)
451 if ((ubrlcr & UBRLCR_WRDLEN_MASK) == UBRLCR_WRDLEN7)
456 quot = ubrlcr & UBRLCR_BAUD_MASK;
457 *baud = port->uartclk / (16 * (quot + 1));
461 static int uart_clps711x_console_setup(struct console *co, char *options)
463 int baud = 38400, bits = 8, parity = 'n', flow = 'n';
464 struct clps711x_port *s = (struct clps711x_port *)co->data;
465 struct uart_port *port = &s->port[(co->index > 0) ? co->index : 0];
468 uart_parse_options(options, &baud, &parity, &bits, &flow);
470 uart_clps711x_console_get_options(port, &baud, &parity, &bits);
472 return uart_set_options(port, co, baud, parity, bits, flow);
476 static int __devinit uart_clps711x_probe(struct platform_device *pdev)
478 struct clps711x_port *s;
481 s = devm_kzalloc(&pdev->dev, sizeof(struct clps711x_port), GFP_KERNEL);
483 dev_err(&pdev->dev, "Error allocating port structure\n");
486 platform_set_drvdata(pdev, s);
488 s->uart.owner = THIS_MODULE;
489 s->uart.dev_name = "ttyCL";
490 s->uart.major = UART_CLPS711X_MAJOR;
491 s->uart.minor = UART_CLPS711X_MINOR;
492 s->uart.nr = UART_CLPS711X_NR;
493 #ifdef CONFIG_SERIAL_CLPS711X_CONSOLE
494 s->uart.cons = &s->console;
495 s->uart.cons->device = uart_console_device;
496 s->uart.cons->write = uart_clps711x_console_write;
497 s->uart.cons->setup = uart_clps711x_console_setup;
498 s->uart.cons->flags = CON_PRINTBUFFER;
499 s->uart.cons->index = -1;
500 s->uart.cons->data = s;
501 strcpy(s->uart.cons->name, "ttyCL");
503 ret = uart_register_driver(&s->uart);
505 dev_err(&pdev->dev, "Registering UART driver failed\n");
509 for (i = 0; i < UART_CLPS711X_NR; i++) {
511 s->port[i].dev = &pdev->dev;
512 s->port[i].irq = TX_IRQ(&s->port[i]);
513 s->port[i].iobase = SYSCON(&s->port[i]);
514 s->port[i].type = PORT_CLPS711X;
515 s->port[i].fifosize = 16;
516 s->port[i].flags = UPF_SKIP_TEST | UPF_FIXED_TYPE;
517 s->port[i].uartclk = 3686400;
518 s->port[i].ops = &uart_clps711x_ops;
519 WARN_ON(uart_add_one_port(&s->uart, &s->port[i]));
525 platform_set_drvdata(pdev, NULL);
530 static int __devexit uart_clps711x_remove(struct platform_device *pdev)
532 struct clps711x_port *s = platform_get_drvdata(pdev);
535 for (i = 0; i < UART_CLPS711X_NR; i++)
536 uart_remove_one_port(&s->uart, &s->port[i]);
538 uart_unregister_driver(&s->uart);
539 platform_set_drvdata(pdev, NULL);
544 static struct platform_driver clps711x_uart_driver = {
546 .name = UART_CLPS711X_NAME,
547 .owner = THIS_MODULE,
549 .probe = uart_clps711x_probe,
550 .remove = __devexit_p(uart_clps711x_remove),
552 module_platform_driver(clps711x_uart_driver);
554 static struct platform_device clps711x_uart_device = {
555 .name = UART_CLPS711X_NAME,
558 static int __init uart_clps711x_init(void)
560 return platform_device_register(&clps711x_uart_device);
562 module_init(uart_clps711x_init);
564 static void __exit uart_clps711x_exit(void)
566 platform_device_unregister(&clps711x_uart_device);
568 module_exit(uart_clps711x_exit);
570 MODULE_AUTHOR("Deep Blue Solutions Ltd");
571 MODULE_DESCRIPTION("CLPS711X serial driver");
572 MODULE_LICENSE("GPL");