Linux 3.12.39
[linux/fpc-iii.git] / drivers / tty / serial / ar933x_uart.c
blobacd03af7cd52287759a5b06275119f0856325fc0
1 /*
2 * Atheros AR933X SoC built-in UART driver
4 * Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
6 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 as published
10 * by the Free Software Foundation.
13 #include <linux/module.h>
14 #include <linux/ioport.h>
15 #include <linux/init.h>
16 #include <linux/console.h>
17 #include <linux/sysrq.h>
18 #include <linux/delay.h>
19 #include <linux/platform_device.h>
20 #include <linux/of.h>
21 #include <linux/of_platform.h>
22 #include <linux/tty.h>
23 #include <linux/tty_flip.h>
24 #include <linux/serial_core.h>
25 #include <linux/serial.h>
26 #include <linux/slab.h>
27 #include <linux/io.h>
28 #include <linux/irq.h>
29 #include <linux/clk.h>
31 #include <asm/div64.h>
33 #include <asm/mach-ath79/ar933x_uart.h>
35 #define DRIVER_NAME "ar933x-uart"
37 #define AR933X_UART_MAX_SCALE 0xff
38 #define AR933X_UART_MAX_STEP 0xffff
40 #define AR933X_UART_MIN_BAUD 300
41 #define AR933X_UART_MAX_BAUD 3000000
43 #define AR933X_DUMMY_STATUS_RD 0x01
45 static struct uart_driver ar933x_uart_driver;
47 struct ar933x_uart_port {
48 struct uart_port port;
49 unsigned int ier; /* shadow Interrupt Enable Register */
50 unsigned int min_baud;
51 unsigned int max_baud;
52 struct clk *clk;
55 static inline bool ar933x_uart_console_enabled(void)
57 return config_enabled(CONFIG_SERIAL_AR933X_CONSOLE);
60 static inline unsigned int ar933x_uart_read(struct ar933x_uart_port *up,
61 int offset)
63 return readl(up->port.membase + offset);
66 static inline void ar933x_uart_write(struct ar933x_uart_port *up,
67 int offset, unsigned int value)
69 writel(value, up->port.membase + offset);
72 static inline void ar933x_uart_rmw(struct ar933x_uart_port *up,
73 unsigned int offset,
74 unsigned int mask,
75 unsigned int val)
77 unsigned int t;
79 t = ar933x_uart_read(up, offset);
80 t &= ~mask;
81 t |= val;
82 ar933x_uart_write(up, offset, t);
85 static inline void ar933x_uart_rmw_set(struct ar933x_uart_port *up,
86 unsigned int offset,
87 unsigned int val)
89 ar933x_uart_rmw(up, offset, 0, val);
92 static inline void ar933x_uart_rmw_clear(struct ar933x_uart_port *up,
93 unsigned int offset,
94 unsigned int val)
96 ar933x_uart_rmw(up, offset, val, 0);
99 static inline void ar933x_uart_start_tx_interrupt(struct ar933x_uart_port *up)
101 up->ier |= AR933X_UART_INT_TX_EMPTY;
102 ar933x_uart_write(up, AR933X_UART_INT_EN_REG, up->ier);
105 static inline void ar933x_uart_stop_tx_interrupt(struct ar933x_uart_port *up)
107 up->ier &= ~AR933X_UART_INT_TX_EMPTY;
108 ar933x_uart_write(up, AR933X_UART_INT_EN_REG, up->ier);
111 static inline void ar933x_uart_putc(struct ar933x_uart_port *up, int ch)
113 unsigned int rdata;
115 rdata = ch & AR933X_UART_DATA_TX_RX_MASK;
116 rdata |= AR933X_UART_DATA_TX_CSR;
117 ar933x_uart_write(up, AR933X_UART_DATA_REG, rdata);
120 static unsigned int ar933x_uart_tx_empty(struct uart_port *port)
122 struct ar933x_uart_port *up = (struct ar933x_uart_port *) port;
123 unsigned long flags;
124 unsigned int rdata;
126 spin_lock_irqsave(&up->port.lock, flags);
127 rdata = ar933x_uart_read(up, AR933X_UART_DATA_REG);
128 spin_unlock_irqrestore(&up->port.lock, flags);
130 return (rdata & AR933X_UART_DATA_TX_CSR) ? 0 : TIOCSER_TEMT;
133 static unsigned int ar933x_uart_get_mctrl(struct uart_port *port)
135 return TIOCM_CAR;
138 static void ar933x_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
142 static void ar933x_uart_start_tx(struct uart_port *port)
144 struct ar933x_uart_port *up = (struct ar933x_uart_port *) port;
146 ar933x_uart_start_tx_interrupt(up);
149 static void ar933x_uart_stop_tx(struct uart_port *port)
151 struct ar933x_uart_port *up = (struct ar933x_uart_port *) port;
153 ar933x_uart_stop_tx_interrupt(up);
156 static void ar933x_uart_stop_rx(struct uart_port *port)
158 struct ar933x_uart_port *up = (struct ar933x_uart_port *) port;
160 up->ier &= ~AR933X_UART_INT_RX_VALID;
161 ar933x_uart_write(up, AR933X_UART_INT_EN_REG, up->ier);
164 static void ar933x_uart_break_ctl(struct uart_port *port, int break_state)
166 struct ar933x_uart_port *up = (struct ar933x_uart_port *) port;
167 unsigned long flags;
169 spin_lock_irqsave(&up->port.lock, flags);
170 if (break_state == -1)
171 ar933x_uart_rmw_set(up, AR933X_UART_CS_REG,
172 AR933X_UART_CS_TX_BREAK);
173 else
174 ar933x_uart_rmw_clear(up, AR933X_UART_CS_REG,
175 AR933X_UART_CS_TX_BREAK);
176 spin_unlock_irqrestore(&up->port.lock, flags);
179 static void ar933x_uart_enable_ms(struct uart_port *port)
184 * baudrate = (clk / (scale + 1)) * (step * (1 / 2^17))
186 static unsigned long ar933x_uart_get_baud(unsigned int clk,
187 unsigned int scale,
188 unsigned int step)
190 u64 t;
191 u32 div;
193 div = (2 << 16) * (scale + 1);
194 t = clk;
195 t *= step;
196 t += (div / 2);
197 do_div(t, div);
199 return t;
202 static void ar933x_uart_get_scale_step(unsigned int clk,
203 unsigned int baud,
204 unsigned int *scale,
205 unsigned int *step)
207 unsigned int tscale;
208 long min_diff;
210 *scale = 0;
211 *step = 0;
213 min_diff = baud;
214 for (tscale = 0; tscale < AR933X_UART_MAX_SCALE; tscale++) {
215 u64 tstep;
216 int diff;
218 tstep = baud * (tscale + 1);
219 tstep *= (2 << 16);
220 do_div(tstep, clk);
222 if (tstep > AR933X_UART_MAX_STEP)
223 break;
225 diff = abs(ar933x_uart_get_baud(clk, tscale, tstep) - baud);
226 if (diff < min_diff) {
227 min_diff = diff;
228 *scale = tscale;
229 *step = tstep;
234 static void ar933x_uart_set_termios(struct uart_port *port,
235 struct ktermios *new,
236 struct ktermios *old)
238 struct ar933x_uart_port *up = (struct ar933x_uart_port *) port;
239 unsigned int cs;
240 unsigned long flags;
241 unsigned int baud, scale, step;
243 /* Only CS8 is supported */
244 new->c_cflag &= ~CSIZE;
245 new->c_cflag |= CS8;
247 /* Only one stop bit is supported */
248 new->c_cflag &= ~CSTOPB;
250 cs = 0;
251 if (new->c_cflag & PARENB) {
252 if (!(new->c_cflag & PARODD))
253 cs |= AR933X_UART_CS_PARITY_EVEN;
254 else
255 cs |= AR933X_UART_CS_PARITY_ODD;
256 } else {
257 cs |= AR933X_UART_CS_PARITY_NONE;
260 /* Mark/space parity is not supported */
261 new->c_cflag &= ~CMSPAR;
263 baud = uart_get_baud_rate(port, new, old, up->min_baud, up->max_baud);
264 ar933x_uart_get_scale_step(port->uartclk, baud, &scale, &step);
267 * Ok, we're now changing the port state. Do it with
268 * interrupts disabled.
270 spin_lock_irqsave(&up->port.lock, flags);
272 /* disable the UART */
273 ar933x_uart_rmw_clear(up, AR933X_UART_CS_REG,
274 AR933X_UART_CS_IF_MODE_M << AR933X_UART_CS_IF_MODE_S);
276 /* Update the per-port timeout. */
277 uart_update_timeout(port, new->c_cflag, baud);
279 up->port.ignore_status_mask = 0;
281 /* ignore all characters if CREAD is not set */
282 if ((new->c_cflag & CREAD) == 0)
283 up->port.ignore_status_mask |= AR933X_DUMMY_STATUS_RD;
285 ar933x_uart_write(up, AR933X_UART_CLOCK_REG,
286 scale << AR933X_UART_CLOCK_SCALE_S | step);
288 /* setup configuration register */
289 ar933x_uart_rmw(up, AR933X_UART_CS_REG, AR933X_UART_CS_PARITY_M, cs);
291 /* enable host interrupt */
292 ar933x_uart_rmw_set(up, AR933X_UART_CS_REG,
293 AR933X_UART_CS_HOST_INT_EN);
295 /* reenable the UART */
296 ar933x_uart_rmw(up, AR933X_UART_CS_REG,
297 AR933X_UART_CS_IF_MODE_M << AR933X_UART_CS_IF_MODE_S,
298 AR933X_UART_CS_IF_MODE_DCE << AR933X_UART_CS_IF_MODE_S);
300 spin_unlock_irqrestore(&up->port.lock, flags);
302 if (tty_termios_baud_rate(new))
303 tty_termios_encode_baud_rate(new, baud, baud);
306 static void ar933x_uart_rx_chars(struct ar933x_uart_port *up)
308 struct tty_port *port = &up->port.state->port;
309 int max_count = 256;
311 do {
312 unsigned int rdata;
313 unsigned char ch;
315 rdata = ar933x_uart_read(up, AR933X_UART_DATA_REG);
316 if ((rdata & AR933X_UART_DATA_RX_CSR) == 0)
317 break;
319 /* remove the character from the FIFO */
320 ar933x_uart_write(up, AR933X_UART_DATA_REG,
321 AR933X_UART_DATA_RX_CSR);
323 up->port.icount.rx++;
324 ch = rdata & AR933X_UART_DATA_TX_RX_MASK;
326 if (uart_handle_sysrq_char(&up->port, ch))
327 continue;
329 if ((up->port.ignore_status_mask & AR933X_DUMMY_STATUS_RD) == 0)
330 tty_insert_flip_char(port, ch, TTY_NORMAL);
331 } while (max_count-- > 0);
333 spin_unlock(&up->port.lock);
334 tty_flip_buffer_push(port);
335 spin_lock(&up->port.lock);
338 static void ar933x_uart_tx_chars(struct ar933x_uart_port *up)
340 struct circ_buf *xmit = &up->port.state->xmit;
341 int count;
343 if (uart_tx_stopped(&up->port))
344 return;
346 count = up->port.fifosize;
347 do {
348 unsigned int rdata;
350 rdata = ar933x_uart_read(up, AR933X_UART_DATA_REG);
351 if ((rdata & AR933X_UART_DATA_TX_CSR) == 0)
352 break;
354 if (up->port.x_char) {
355 ar933x_uart_putc(up, up->port.x_char);
356 up->port.icount.tx++;
357 up->port.x_char = 0;
358 continue;
361 if (uart_circ_empty(xmit))
362 break;
364 ar933x_uart_putc(up, xmit->buf[xmit->tail]);
366 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
367 up->port.icount.tx++;
368 } while (--count > 0);
370 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
371 uart_write_wakeup(&up->port);
373 if (!uart_circ_empty(xmit))
374 ar933x_uart_start_tx_interrupt(up);
377 static irqreturn_t ar933x_uart_interrupt(int irq, void *dev_id)
379 struct ar933x_uart_port *up = dev_id;
380 unsigned int status;
382 status = ar933x_uart_read(up, AR933X_UART_CS_REG);
383 if ((status & AR933X_UART_CS_HOST_INT) == 0)
384 return IRQ_NONE;
386 spin_lock(&up->port.lock);
388 status = ar933x_uart_read(up, AR933X_UART_INT_REG);
389 status &= ar933x_uart_read(up, AR933X_UART_INT_EN_REG);
391 if (status & AR933X_UART_INT_RX_VALID) {
392 ar933x_uart_write(up, AR933X_UART_INT_REG,
393 AR933X_UART_INT_RX_VALID);
394 ar933x_uart_rx_chars(up);
397 if (status & AR933X_UART_INT_TX_EMPTY) {
398 ar933x_uart_write(up, AR933X_UART_INT_REG,
399 AR933X_UART_INT_TX_EMPTY);
400 ar933x_uart_stop_tx_interrupt(up);
401 ar933x_uart_tx_chars(up);
404 spin_unlock(&up->port.lock);
406 return IRQ_HANDLED;
409 static int ar933x_uart_startup(struct uart_port *port)
411 struct ar933x_uart_port *up = (struct ar933x_uart_port *) port;
412 unsigned long flags;
413 int ret;
415 ret = request_irq(up->port.irq, ar933x_uart_interrupt,
416 up->port.irqflags, dev_name(up->port.dev), up);
417 if (ret)
418 return ret;
420 spin_lock_irqsave(&up->port.lock, flags);
422 /* Enable HOST interrupts */
423 ar933x_uart_rmw_set(up, AR933X_UART_CS_REG,
424 AR933X_UART_CS_HOST_INT_EN);
426 /* Enable RX interrupts */
427 up->ier = AR933X_UART_INT_RX_VALID;
428 ar933x_uart_write(up, AR933X_UART_INT_EN_REG, up->ier);
430 spin_unlock_irqrestore(&up->port.lock, flags);
432 return 0;
435 static void ar933x_uart_shutdown(struct uart_port *port)
437 struct ar933x_uart_port *up = (struct ar933x_uart_port *) port;
439 /* Disable all interrupts */
440 up->ier = 0;
441 ar933x_uart_write(up, AR933X_UART_INT_EN_REG, up->ier);
443 /* Disable break condition */
444 ar933x_uart_rmw_clear(up, AR933X_UART_CS_REG,
445 AR933X_UART_CS_TX_BREAK);
447 free_irq(up->port.irq, up);
450 static const char *ar933x_uart_type(struct uart_port *port)
452 return (port->type == PORT_AR933X) ? "AR933X UART" : NULL;
455 static void ar933x_uart_release_port(struct uart_port *port)
457 /* Nothing to release ... */
460 static int ar933x_uart_request_port(struct uart_port *port)
462 /* UARTs always present */
463 return 0;
466 static void ar933x_uart_config_port(struct uart_port *port, int flags)
468 if (flags & UART_CONFIG_TYPE)
469 port->type = PORT_AR933X;
472 static int ar933x_uart_verify_port(struct uart_port *port,
473 struct serial_struct *ser)
475 struct ar933x_uart_port *up = (struct ar933x_uart_port *) port;
477 if (ser->type != PORT_UNKNOWN &&
478 ser->type != PORT_AR933X)
479 return -EINVAL;
481 if (ser->irq < 0 || ser->irq >= NR_IRQS)
482 return -EINVAL;
484 if (ser->baud_base < up->min_baud ||
485 ser->baud_base > up->max_baud)
486 return -EINVAL;
488 return 0;
491 static struct uart_ops ar933x_uart_ops = {
492 .tx_empty = ar933x_uart_tx_empty,
493 .set_mctrl = ar933x_uart_set_mctrl,
494 .get_mctrl = ar933x_uart_get_mctrl,
495 .stop_tx = ar933x_uart_stop_tx,
496 .start_tx = ar933x_uart_start_tx,
497 .stop_rx = ar933x_uart_stop_rx,
498 .enable_ms = ar933x_uart_enable_ms,
499 .break_ctl = ar933x_uart_break_ctl,
500 .startup = ar933x_uart_startup,
501 .shutdown = ar933x_uart_shutdown,
502 .set_termios = ar933x_uart_set_termios,
503 .type = ar933x_uart_type,
504 .release_port = ar933x_uart_release_port,
505 .request_port = ar933x_uart_request_port,
506 .config_port = ar933x_uart_config_port,
507 .verify_port = ar933x_uart_verify_port,
510 static struct ar933x_uart_port *
511 ar933x_console_ports[CONFIG_SERIAL_AR933X_NR_UARTS];
513 static void ar933x_uart_wait_xmitr(struct ar933x_uart_port *up)
515 unsigned int status;
516 unsigned int timeout = 60000;
518 /* Wait up to 60ms for the character(s) to be sent. */
519 do {
520 status = ar933x_uart_read(up, AR933X_UART_DATA_REG);
521 if (--timeout == 0)
522 break;
523 udelay(1);
524 } while ((status & AR933X_UART_DATA_TX_CSR) == 0);
527 static void ar933x_uart_console_putchar(struct uart_port *port, int ch)
529 struct ar933x_uart_port *up = (struct ar933x_uart_port *) port;
531 ar933x_uart_wait_xmitr(up);
532 ar933x_uart_putc(up, ch);
535 static void ar933x_uart_console_write(struct console *co, const char *s,
536 unsigned int count)
538 struct ar933x_uart_port *up = ar933x_console_ports[co->index];
539 unsigned long flags;
540 unsigned int int_en;
541 int locked = 1;
543 local_irq_save(flags);
545 if (up->port.sysrq)
546 locked = 0;
547 else if (oops_in_progress)
548 locked = spin_trylock(&up->port.lock);
549 else
550 spin_lock(&up->port.lock);
553 * First save the IER then disable the interrupts
555 int_en = ar933x_uart_read(up, AR933X_UART_INT_EN_REG);
556 ar933x_uart_write(up, AR933X_UART_INT_EN_REG, 0);
558 uart_console_write(&up->port, s, count, ar933x_uart_console_putchar);
561 * Finally, wait for transmitter to become empty
562 * and restore the IER
564 ar933x_uart_wait_xmitr(up);
565 ar933x_uart_write(up, AR933X_UART_INT_EN_REG, int_en);
567 ar933x_uart_write(up, AR933X_UART_INT_REG, AR933X_UART_INT_ALLINTS);
569 if (locked)
570 spin_unlock(&up->port.lock);
572 local_irq_restore(flags);
575 static int ar933x_uart_console_setup(struct console *co, char *options)
577 struct ar933x_uart_port *up;
578 int baud = 115200;
579 int bits = 8;
580 int parity = 'n';
581 int flow = 'n';
583 if (co->index < 0 || co->index >= CONFIG_SERIAL_AR933X_NR_UARTS)
584 return -EINVAL;
586 up = ar933x_console_ports[co->index];
587 if (!up)
588 return -ENODEV;
590 if (options)
591 uart_parse_options(options, &baud, &parity, &bits, &flow);
593 return uart_set_options(&up->port, co, baud, parity, bits, flow);
596 static struct console ar933x_uart_console = {
597 .name = "ttyATH",
598 .write = ar933x_uart_console_write,
599 .device = uart_console_device,
600 .setup = ar933x_uart_console_setup,
601 .flags = CON_PRINTBUFFER,
602 .index = -1,
603 .data = &ar933x_uart_driver,
606 static void ar933x_uart_add_console_port(struct ar933x_uart_port *up)
608 if (!ar933x_uart_console_enabled())
609 return;
611 ar933x_console_ports[up->port.line] = up;
614 static struct uart_driver ar933x_uart_driver = {
615 .owner = THIS_MODULE,
616 .driver_name = DRIVER_NAME,
617 .dev_name = "ttyATH",
618 .nr = CONFIG_SERIAL_AR933X_NR_UARTS,
619 .cons = NULL, /* filled in runtime */
622 static int ar933x_uart_probe(struct platform_device *pdev)
624 struct ar933x_uart_port *up;
625 struct uart_port *port;
626 struct resource *mem_res;
627 struct resource *irq_res;
628 struct device_node *np;
629 unsigned int baud;
630 int id;
631 int ret;
633 np = pdev->dev.of_node;
634 if (config_enabled(CONFIG_OF) && np) {
635 id = of_alias_get_id(np, "serial");
636 if (id < 0) {
637 dev_err(&pdev->dev, "unable to get alias id, err=%d\n",
638 id);
639 return id;
641 } else {
642 id = pdev->id;
643 if (id == -1)
644 id = 0;
647 if (id > CONFIG_SERIAL_AR933X_NR_UARTS)
648 return -EINVAL;
650 irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
651 if (!irq_res) {
652 dev_err(&pdev->dev, "no IRQ resource\n");
653 return -EINVAL;
656 up = devm_kzalloc(&pdev->dev, sizeof(struct ar933x_uart_port),
657 GFP_KERNEL);
658 if (!up)
659 return -ENOMEM;
661 up->clk = devm_clk_get(&pdev->dev, "uart");
662 if (IS_ERR(up->clk)) {
663 dev_err(&pdev->dev, "unable to get UART clock\n");
664 return PTR_ERR(up->clk);
667 port = &up->port;
669 mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
670 port->membase = devm_ioremap_resource(&pdev->dev, mem_res);
671 if (IS_ERR(port->membase))
672 return PTR_ERR(port->membase);
674 ret = clk_prepare_enable(up->clk);
675 if (ret)
676 return ret;
678 port->uartclk = clk_get_rate(up->clk);
679 if (!port->uartclk) {
680 ret = -EINVAL;
681 goto err_disable_clk;
684 port->mapbase = mem_res->start;
685 port->line = id;
686 port->irq = irq_res->start;
687 port->dev = &pdev->dev;
688 port->type = PORT_AR933X;
689 port->iotype = UPIO_MEM32;
691 port->regshift = 2;
692 port->fifosize = AR933X_UART_FIFO_SIZE;
693 port->ops = &ar933x_uart_ops;
695 baud = ar933x_uart_get_baud(port->uartclk, AR933X_UART_MAX_SCALE, 1);
696 up->min_baud = max_t(unsigned int, baud, AR933X_UART_MIN_BAUD);
698 baud = ar933x_uart_get_baud(port->uartclk, 0, AR933X_UART_MAX_STEP);
699 up->max_baud = min_t(unsigned int, baud, AR933X_UART_MAX_BAUD);
701 ar933x_uart_add_console_port(up);
703 ret = uart_add_one_port(&ar933x_uart_driver, &up->port);
704 if (ret)
705 goto err_disable_clk;
707 platform_set_drvdata(pdev, up);
708 return 0;
710 err_disable_clk:
711 clk_disable_unprepare(up->clk);
712 return ret;
715 static int ar933x_uart_remove(struct platform_device *pdev)
717 struct ar933x_uart_port *up;
719 up = platform_get_drvdata(pdev);
721 if (up) {
722 uart_remove_one_port(&ar933x_uart_driver, &up->port);
723 clk_disable_unprepare(up->clk);
726 return 0;
729 #ifdef CONFIG_OF
730 static const struct of_device_id ar933x_uart_of_ids[] = {
731 { .compatible = "qca,ar9330-uart" },
734 MODULE_DEVICE_TABLE(of, ar933x_uart_of_ids);
735 #endif
737 static struct platform_driver ar933x_uart_platform_driver = {
738 .probe = ar933x_uart_probe,
739 .remove = ar933x_uart_remove,
740 .driver = {
741 .name = DRIVER_NAME,
742 .owner = THIS_MODULE,
743 .of_match_table = of_match_ptr(ar933x_uart_of_ids),
747 static int __init ar933x_uart_init(void)
749 int ret;
751 if (ar933x_uart_console_enabled())
752 ar933x_uart_driver.cons = &ar933x_uart_console;
754 ret = uart_register_driver(&ar933x_uart_driver);
755 if (ret)
756 goto err_out;
758 ret = platform_driver_register(&ar933x_uart_platform_driver);
759 if (ret)
760 goto err_unregister_uart_driver;
762 return 0;
764 err_unregister_uart_driver:
765 uart_unregister_driver(&ar933x_uart_driver);
766 err_out:
767 return ret;
770 static void __exit ar933x_uart_exit(void)
772 platform_driver_unregister(&ar933x_uart_platform_driver);
773 uart_unregister_driver(&ar933x_uart_driver);
776 module_init(ar933x_uart_init);
777 module_exit(ar933x_uart_exit);
779 MODULE_DESCRIPTION("Atheros AR933X UART driver");
780 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
781 MODULE_LICENSE("GPL v2");
782 MODULE_ALIAS("platform:" DRIVER_NAME);