Xilinx: ARM: adding xylon IP snippet dts file
[linux-2.6-xlnx.git] / drivers / tty / serial / omap-serial.c
blob47cadf474149fe957a179458f24dc66ea6a57f9f
1 /*
2 * Driver for OMAP-UART controller.
3 * Based on drivers/serial/8250.c
5 * Copyright (C) 2010 Texas Instruments.
7 * Authors:
8 * Govindraj R <govindraj.raja@ti.com>
9 * Thara Gopinath <thara@ti.com>
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
16 * Note: This driver is made separate from 8250 driver as we cannot
17 * over load 8250 driver with omap platform specific configuration for
18 * features like DMA, it makes easier to implement features like DMA and
19 * hardware flow control and software flow control configuration with
20 * this driver as required for the omap-platform.
23 #if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
24 #define SUPPORT_SYSRQ
25 #endif
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/console.h>
30 #include <linux/serial_reg.h>
31 #include <linux/delay.h>
32 #include <linux/slab.h>
33 #include <linux/tty.h>
34 #include <linux/tty_flip.h>
35 #include <linux/io.h>
36 #include <linux/dma-mapping.h>
37 #include <linux/clk.h>
38 #include <linux/serial_core.h>
39 #include <linux/irq.h>
41 #include <plat/dma.h>
42 #include <plat/dmtimer.h>
43 #include <plat/omap-serial.h>
45 static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
47 /* Forward declaration of functions */
48 static void uart_tx_dma_callback(int lch, u16 ch_status, void *data);
49 static void serial_omap_rx_timeout(unsigned long uart_no);
50 static int serial_omap_start_rxdma(struct uart_omap_port *up);
52 static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
54 offset <<= up->port.regshift;
55 return readw(up->port.membase + offset);
58 static inline void serial_out(struct uart_omap_port *up, int offset, int value)
60 offset <<= up->port.regshift;
61 writew(value, up->port.membase + offset);
64 static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
66 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
67 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
68 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
69 serial_out(up, UART_FCR, 0);
73 * serial_omap_get_divisor - calculate divisor value
74 * @port: uart port info
75 * @baud: baudrate for which divisor needs to be calculated.
77 * We have written our own function to get the divisor so as to support
78 * 13x mode. 3Mbps Baudrate as an different divisor.
79 * Reference OMAP TRM Chapter 17:
80 * Table 17-1. UART Mode Baud Rates, Divisor Values, and Error Rates
81 * referring to oversampling - divisor value
82 * baudrate 460,800 to 3,686,400 all have divisor 13
83 * except 3,000,000 which has divisor value 16
85 static unsigned int
86 serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
88 unsigned int divisor;
90 if (baud > OMAP_MODE13X_SPEED && baud != 3000000)
91 divisor = 13;
92 else
93 divisor = 16;
94 return port->uartclk/(baud * divisor);
97 static void serial_omap_stop_rxdma(struct uart_omap_port *up)
99 if (up->uart_dma.rx_dma_used) {
100 del_timer(&up->uart_dma.rx_timer);
101 omap_stop_dma(up->uart_dma.rx_dma_channel);
102 omap_free_dma(up->uart_dma.rx_dma_channel);
103 up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE;
104 up->uart_dma.rx_dma_used = false;
108 static void serial_omap_enable_ms(struct uart_port *port)
110 struct uart_omap_port *up = (struct uart_omap_port *)port;
112 dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->pdev->id);
113 up->ier |= UART_IER_MSI;
114 serial_out(up, UART_IER, up->ier);
117 static void serial_omap_stop_tx(struct uart_port *port)
119 struct uart_omap_port *up = (struct uart_omap_port *)port;
121 if (up->use_dma &&
122 up->uart_dma.tx_dma_channel != OMAP_UART_DMA_CH_FREE) {
124 * Check if dma is still active. If yes do nothing,
125 * return. Else stop dma
127 if (omap_get_dma_active_status(up->uart_dma.tx_dma_channel))
128 return;
129 omap_stop_dma(up->uart_dma.tx_dma_channel);
130 omap_free_dma(up->uart_dma.tx_dma_channel);
131 up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
134 if (up->ier & UART_IER_THRI) {
135 up->ier &= ~UART_IER_THRI;
136 serial_out(up, UART_IER, up->ier);
140 static void serial_omap_stop_rx(struct uart_port *port)
142 struct uart_omap_port *up = (struct uart_omap_port *)port;
144 if (up->use_dma)
145 serial_omap_stop_rxdma(up);
146 up->ier &= ~UART_IER_RLSI;
147 up->port.read_status_mask &= ~UART_LSR_DR;
148 serial_out(up, UART_IER, up->ier);
151 static inline void receive_chars(struct uart_omap_port *up, int *status)
153 struct tty_struct *tty = up->port.state->port.tty;
154 unsigned int flag;
155 unsigned char ch, lsr = *status;
156 int max_count = 256;
158 do {
159 if (likely(lsr & UART_LSR_DR))
160 ch = serial_in(up, UART_RX);
161 flag = TTY_NORMAL;
162 up->port.icount.rx++;
164 if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) {
166 * For statistics only
168 if (lsr & UART_LSR_BI) {
169 lsr &= ~(UART_LSR_FE | UART_LSR_PE);
170 up->port.icount.brk++;
172 * We do the SysRQ and SAK checking
173 * here because otherwise the break
174 * may get masked by ignore_status_mask
175 * or read_status_mask.
177 if (uart_handle_break(&up->port))
178 goto ignore_char;
179 } else if (lsr & UART_LSR_PE) {
180 up->port.icount.parity++;
181 } else if (lsr & UART_LSR_FE) {
182 up->port.icount.frame++;
185 if (lsr & UART_LSR_OE)
186 up->port.icount.overrun++;
189 * Mask off conditions which should be ignored.
191 lsr &= up->port.read_status_mask;
193 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
194 if (up->port.line == up->port.cons->index) {
195 /* Recover the break flag from console xmit */
196 lsr |= up->lsr_break_flag;
198 #endif
199 if (lsr & UART_LSR_BI)
200 flag = TTY_BREAK;
201 else if (lsr & UART_LSR_PE)
202 flag = TTY_PARITY;
203 else if (lsr & UART_LSR_FE)
204 flag = TTY_FRAME;
207 if (uart_handle_sysrq_char(&up->port, ch))
208 goto ignore_char;
209 uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
210 ignore_char:
211 lsr = serial_in(up, UART_LSR);
212 } while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (max_count-- > 0));
213 spin_unlock(&up->port.lock);
214 tty_flip_buffer_push(tty);
215 spin_lock(&up->port.lock);
218 static void transmit_chars(struct uart_omap_port *up)
220 struct circ_buf *xmit = &up->port.state->xmit;
221 int count;
223 if (up->port.x_char) {
224 serial_out(up, UART_TX, up->port.x_char);
225 up->port.icount.tx++;
226 up->port.x_char = 0;
227 return;
229 if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
230 serial_omap_stop_tx(&up->port);
231 return;
233 count = up->port.fifosize / 4;
234 do {
235 serial_out(up, UART_TX, xmit->buf[xmit->tail]);
236 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
237 up->port.icount.tx++;
238 if (uart_circ_empty(xmit))
239 break;
240 } while (--count > 0);
242 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
243 uart_write_wakeup(&up->port);
245 if (uart_circ_empty(xmit))
246 serial_omap_stop_tx(&up->port);
249 static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
251 if (!(up->ier & UART_IER_THRI)) {
252 up->ier |= UART_IER_THRI;
253 serial_out(up, UART_IER, up->ier);
257 static void serial_omap_start_tx(struct uart_port *port)
259 struct uart_omap_port *up = (struct uart_omap_port *)port;
260 struct circ_buf *xmit;
261 unsigned int start;
262 int ret = 0;
264 if (!up->use_dma) {
265 serial_omap_enable_ier_thri(up);
266 return;
269 if (up->uart_dma.tx_dma_used)
270 return;
272 xmit = &up->port.state->xmit;
274 if (up->uart_dma.tx_dma_channel == OMAP_UART_DMA_CH_FREE) {
275 ret = omap_request_dma(up->uart_dma.uart_dma_tx,
276 "UART Tx DMA",
277 (void *)uart_tx_dma_callback, up,
278 &(up->uart_dma.tx_dma_channel));
280 if (ret < 0) {
281 serial_omap_enable_ier_thri(up);
282 return;
285 spin_lock(&(up->uart_dma.tx_lock));
286 up->uart_dma.tx_dma_used = true;
287 spin_unlock(&(up->uart_dma.tx_lock));
289 start = up->uart_dma.tx_buf_dma_phys +
290 (xmit->tail & (UART_XMIT_SIZE - 1));
292 up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
294 * It is a circular buffer. See if the buffer has wounded back.
295 * If yes it will have to be transferred in two separate dma
296 * transfers
298 if (start + up->uart_dma.tx_buf_size >=
299 up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
300 up->uart_dma.tx_buf_size =
301 (up->uart_dma.tx_buf_dma_phys +
302 UART_XMIT_SIZE) - start;
304 omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
305 OMAP_DMA_AMODE_CONSTANT,
306 up->uart_dma.uart_base, 0, 0);
307 omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
308 OMAP_DMA_AMODE_POST_INC, start, 0, 0);
309 omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
310 OMAP_DMA_DATA_TYPE_S8,
311 up->uart_dma.tx_buf_size, 1,
312 OMAP_DMA_SYNC_ELEMENT,
313 up->uart_dma.uart_dma_tx, 0);
314 /* FIXME: Cache maintenance needed here? */
315 omap_start_dma(up->uart_dma.tx_dma_channel);
318 static unsigned int check_modem_status(struct uart_omap_port *up)
320 unsigned int status;
322 status = serial_in(up, UART_MSR);
323 status |= up->msr_saved_flags;
324 up->msr_saved_flags = 0;
325 if ((status & UART_MSR_ANY_DELTA) == 0)
326 return status;
328 if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
329 up->port.state != NULL) {
330 if (status & UART_MSR_TERI)
331 up->port.icount.rng++;
332 if (status & UART_MSR_DDSR)
333 up->port.icount.dsr++;
334 if (status & UART_MSR_DDCD)
335 uart_handle_dcd_change
336 (&up->port, status & UART_MSR_DCD);
337 if (status & UART_MSR_DCTS)
338 uart_handle_cts_change
339 (&up->port, status & UART_MSR_CTS);
340 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
343 return status;
347 * serial_omap_irq() - This handles the interrupt from one port
348 * @irq: uart port irq number
349 * @dev_id: uart port info
351 static inline irqreturn_t serial_omap_irq(int irq, void *dev_id)
353 struct uart_omap_port *up = dev_id;
354 unsigned int iir, lsr;
355 unsigned long flags;
357 iir = serial_in(up, UART_IIR);
358 if (iir & UART_IIR_NO_INT)
359 return IRQ_NONE;
361 spin_lock_irqsave(&up->port.lock, flags);
362 lsr = serial_in(up, UART_LSR);
363 if (iir & UART_IIR_RLSI) {
364 if (!up->use_dma) {
365 if (lsr & UART_LSR_DR)
366 receive_chars(up, &lsr);
367 } else {
368 up->ier &= ~(UART_IER_RDI | UART_IER_RLSI);
369 serial_out(up, UART_IER, up->ier);
370 if ((serial_omap_start_rxdma(up) != 0) &&
371 (lsr & UART_LSR_DR))
372 receive_chars(up, &lsr);
376 check_modem_status(up);
377 if ((lsr & UART_LSR_THRE) && (iir & UART_IIR_THRI))
378 transmit_chars(up);
380 spin_unlock_irqrestore(&up->port.lock, flags);
381 up->port_activity = jiffies;
382 return IRQ_HANDLED;
385 static unsigned int serial_omap_tx_empty(struct uart_port *port)
387 struct uart_omap_port *up = (struct uart_omap_port *)port;
388 unsigned long flags = 0;
389 unsigned int ret = 0;
391 dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->pdev->id);
392 spin_lock_irqsave(&up->port.lock, flags);
393 ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
394 spin_unlock_irqrestore(&up->port.lock, flags);
396 return ret;
399 static unsigned int serial_omap_get_mctrl(struct uart_port *port)
401 struct uart_omap_port *up = (struct uart_omap_port *)port;
402 unsigned char status;
403 unsigned int ret = 0;
405 status = check_modem_status(up);
406 dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->pdev->id);
408 if (status & UART_MSR_DCD)
409 ret |= TIOCM_CAR;
410 if (status & UART_MSR_RI)
411 ret |= TIOCM_RNG;
412 if (status & UART_MSR_DSR)
413 ret |= TIOCM_DSR;
414 if (status & UART_MSR_CTS)
415 ret |= TIOCM_CTS;
416 return ret;
419 static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
421 struct uart_omap_port *up = (struct uart_omap_port *)port;
422 unsigned char mcr = 0;
424 dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->pdev->id);
425 if (mctrl & TIOCM_RTS)
426 mcr |= UART_MCR_RTS;
427 if (mctrl & TIOCM_DTR)
428 mcr |= UART_MCR_DTR;
429 if (mctrl & TIOCM_OUT1)
430 mcr |= UART_MCR_OUT1;
431 if (mctrl & TIOCM_OUT2)
432 mcr |= UART_MCR_OUT2;
433 if (mctrl & TIOCM_LOOP)
434 mcr |= UART_MCR_LOOP;
436 mcr |= up->mcr;
437 serial_out(up, UART_MCR, mcr);
440 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
442 struct uart_omap_port *up = (struct uart_omap_port *)port;
443 unsigned long flags = 0;
445 dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->pdev->id);
446 spin_lock_irqsave(&up->port.lock, flags);
447 if (break_state == -1)
448 up->lcr |= UART_LCR_SBC;
449 else
450 up->lcr &= ~UART_LCR_SBC;
451 serial_out(up, UART_LCR, up->lcr);
452 spin_unlock_irqrestore(&up->port.lock, flags);
455 static int serial_omap_startup(struct uart_port *port)
457 struct uart_omap_port *up = (struct uart_omap_port *)port;
458 unsigned long flags = 0;
459 int retval;
462 * Allocate the IRQ
464 retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
465 up->name, up);
466 if (retval)
467 return retval;
469 dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->pdev->id);
472 * Clear the FIFO buffers and disable them.
473 * (they will be reenabled in set_termios())
475 serial_omap_clear_fifos(up);
476 /* For Hardware flow control */
477 serial_out(up, UART_MCR, UART_MCR_RTS);
480 * Clear the interrupt registers.
482 (void) serial_in(up, UART_LSR);
483 if (serial_in(up, UART_LSR) & UART_LSR_DR)
484 (void) serial_in(up, UART_RX);
485 (void) serial_in(up, UART_IIR);
486 (void) serial_in(up, UART_MSR);
489 * Now, initialize the UART
491 serial_out(up, UART_LCR, UART_LCR_WLEN8);
492 spin_lock_irqsave(&up->port.lock, flags);
494 * Most PC uarts need OUT2 raised to enable interrupts.
496 up->port.mctrl |= TIOCM_OUT2;
497 serial_omap_set_mctrl(&up->port, up->port.mctrl);
498 spin_unlock_irqrestore(&up->port.lock, flags);
500 up->msr_saved_flags = 0;
501 if (up->use_dma) {
502 free_page((unsigned long)up->port.state->xmit.buf);
503 up->port.state->xmit.buf = dma_alloc_coherent(NULL,
504 UART_XMIT_SIZE,
505 (dma_addr_t *)&(up->uart_dma.tx_buf_dma_phys),
507 init_timer(&(up->uart_dma.rx_timer));
508 up->uart_dma.rx_timer.function = serial_omap_rx_timeout;
509 up->uart_dma.rx_timer.data = up->pdev->id;
510 /* Currently the buffer size is 4KB. Can increase it */
511 up->uart_dma.rx_buf = dma_alloc_coherent(NULL,
512 up->uart_dma.rx_buf_size,
513 (dma_addr_t *)&(up->uart_dma.rx_buf_dma_phys), 0);
516 * Finally, enable interrupts. Note: Modem status interrupts
517 * are set via set_termios(), which will be occurring imminently
518 * anyway, so we don't enable them here.
520 up->ier = UART_IER_RLSI | UART_IER_RDI;
521 serial_out(up, UART_IER, up->ier);
523 /* Enable module level wake up */
524 serial_out(up, UART_OMAP_WER, OMAP_UART_WER_MOD_WKUP);
526 up->port_activity = jiffies;
527 return 0;
530 static void serial_omap_shutdown(struct uart_port *port)
532 struct uart_omap_port *up = (struct uart_omap_port *)port;
533 unsigned long flags = 0;
535 dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->pdev->id);
537 * Disable interrupts from this port
539 up->ier = 0;
540 serial_out(up, UART_IER, 0);
542 spin_lock_irqsave(&up->port.lock, flags);
543 up->port.mctrl &= ~TIOCM_OUT2;
544 serial_omap_set_mctrl(&up->port, up->port.mctrl);
545 spin_unlock_irqrestore(&up->port.lock, flags);
548 * Disable break condition and FIFOs
550 serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
551 serial_omap_clear_fifos(up);
554 * Read data port to reset things, and then free the irq
556 if (serial_in(up, UART_LSR) & UART_LSR_DR)
557 (void) serial_in(up, UART_RX);
558 if (up->use_dma) {
559 dma_free_coherent(up->port.dev,
560 UART_XMIT_SIZE, up->port.state->xmit.buf,
561 up->uart_dma.tx_buf_dma_phys);
562 up->port.state->xmit.buf = NULL;
563 serial_omap_stop_rx(port);
564 dma_free_coherent(up->port.dev,
565 up->uart_dma.rx_buf_size, up->uart_dma.rx_buf,
566 up->uart_dma.rx_buf_dma_phys);
567 up->uart_dma.rx_buf = NULL;
569 free_irq(up->port.irq, up);
572 static inline void
573 serial_omap_configure_xonxoff
574 (struct uart_omap_port *up, struct ktermios *termios)
576 unsigned char efr = 0;
578 up->lcr = serial_in(up, UART_LCR);
579 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
580 up->efr = serial_in(up, UART_EFR);
581 serial_out(up, UART_EFR, up->efr & ~UART_EFR_ECB);
583 serial_out(up, UART_XON1, termios->c_cc[VSTART]);
584 serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
586 /* clear SW control mode bits */
587 efr = up->efr;
588 efr &= OMAP_UART_SW_CLR;
591 * IXON Flag:
592 * Enable XON/XOFF flow control on output.
593 * Transmit XON1, XOFF1
595 if (termios->c_iflag & IXON)
596 efr |= OMAP_UART_SW_TX;
599 * IXOFF Flag:
600 * Enable XON/XOFF flow control on input.
601 * Receiver compares XON1, XOFF1.
603 if (termios->c_iflag & IXOFF)
604 efr |= OMAP_UART_SW_RX;
606 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
607 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
609 up->mcr = serial_in(up, UART_MCR);
612 * IXANY Flag:
613 * Enable any character to restart output.
614 * Operation resumes after receiving any
615 * character after recognition of the XOFF character
617 if (termios->c_iflag & IXANY)
618 up->mcr |= UART_MCR_XONANY;
620 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
621 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
622 serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
623 /* Enable special char function UARTi.EFR_REG[5] and
624 * load the new software flow control mode IXON or IXOFF
625 * and restore the UARTi.EFR_REG[4] ENHANCED_EN value.
627 serial_out(up, UART_EFR, efr | UART_EFR_SCD);
628 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
630 serial_out(up, UART_MCR, up->mcr & ~UART_MCR_TCRTLR);
631 serial_out(up, UART_LCR, up->lcr);
634 static void
635 serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
636 struct ktermios *old)
638 struct uart_omap_port *up = (struct uart_omap_port *)port;
639 unsigned char cval = 0;
640 unsigned char efr = 0;
641 unsigned long flags = 0;
642 unsigned int baud, quot;
644 switch (termios->c_cflag & CSIZE) {
645 case CS5:
646 cval = UART_LCR_WLEN5;
647 break;
648 case CS6:
649 cval = UART_LCR_WLEN6;
650 break;
651 case CS7:
652 cval = UART_LCR_WLEN7;
653 break;
654 default:
655 case CS8:
656 cval = UART_LCR_WLEN8;
657 break;
660 if (termios->c_cflag & CSTOPB)
661 cval |= UART_LCR_STOP;
662 if (termios->c_cflag & PARENB)
663 cval |= UART_LCR_PARITY;
664 if (!(termios->c_cflag & PARODD))
665 cval |= UART_LCR_EPAR;
668 * Ask the core to calculate the divisor for us.
671 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
672 quot = serial_omap_get_divisor(port, baud);
674 up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
675 UART_FCR_ENABLE_FIFO;
676 if (up->use_dma)
677 up->fcr |= UART_FCR_DMA_SELECT;
680 * Ok, we're now changing the port state. Do it with
681 * interrupts disabled.
683 spin_lock_irqsave(&up->port.lock, flags);
686 * Update the per-port timeout.
688 uart_update_timeout(port, termios->c_cflag, baud);
690 up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
691 if (termios->c_iflag & INPCK)
692 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
693 if (termios->c_iflag & (BRKINT | PARMRK))
694 up->port.read_status_mask |= UART_LSR_BI;
697 * Characters to ignore
699 up->port.ignore_status_mask = 0;
700 if (termios->c_iflag & IGNPAR)
701 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
702 if (termios->c_iflag & IGNBRK) {
703 up->port.ignore_status_mask |= UART_LSR_BI;
705 * If we're ignoring parity and break indicators,
706 * ignore overruns too (for real raw support).
708 if (termios->c_iflag & IGNPAR)
709 up->port.ignore_status_mask |= UART_LSR_OE;
713 * ignore all characters if CREAD is not set
715 if ((termios->c_cflag & CREAD) == 0)
716 up->port.ignore_status_mask |= UART_LSR_DR;
719 * Modem status interrupts
721 up->ier &= ~UART_IER_MSI;
722 if (UART_ENABLE_MS(&up->port, termios->c_cflag))
723 up->ier |= UART_IER_MSI;
724 serial_out(up, UART_IER, up->ier);
725 serial_out(up, UART_LCR, cval); /* reset DLAB */
727 /* FIFOs and DMA Settings */
729 /* FCR can be changed only when the
730 * baud clock is not running
731 * DLL_REG and DLH_REG set to 0.
733 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
734 serial_out(up, UART_DLL, 0);
735 serial_out(up, UART_DLM, 0);
736 serial_out(up, UART_LCR, 0);
738 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
740 up->efr = serial_in(up, UART_EFR);
741 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
743 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
744 up->mcr = serial_in(up, UART_MCR);
745 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
746 /* FIFO ENABLE, DMA MODE */
747 serial_out(up, UART_FCR, up->fcr);
748 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
750 if (up->use_dma) {
751 serial_out(up, UART_TI752_TLR, 0);
752 serial_out(up, UART_OMAP_SCR,
753 (UART_FCR_TRIGGER_4 | UART_FCR_TRIGGER_8));
756 serial_out(up, UART_EFR, up->efr);
757 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
758 serial_out(up, UART_MCR, up->mcr);
760 /* Protocol, Baud Rate, and Interrupt Settings */
762 serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
763 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
765 up->efr = serial_in(up, UART_EFR);
766 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
768 serial_out(up, UART_LCR, 0);
769 serial_out(up, UART_IER, 0);
770 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
772 serial_out(up, UART_DLL, quot & 0xff); /* LS of divisor */
773 serial_out(up, UART_DLM, quot >> 8); /* MS of divisor */
775 serial_out(up, UART_LCR, 0);
776 serial_out(up, UART_IER, up->ier);
777 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
779 serial_out(up, UART_EFR, up->efr);
780 serial_out(up, UART_LCR, cval);
782 if (baud > 230400 && baud != 3000000)
783 serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_13X_MODE);
784 else
785 serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_16X_MODE);
787 /* Hardware Flow Control Configuration */
789 if (termios->c_cflag & CRTSCTS) {
790 efr |= (UART_EFR_CTS | UART_EFR_RTS);
791 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
793 up->mcr = serial_in(up, UART_MCR);
794 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
796 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
797 up->efr = serial_in(up, UART_EFR);
798 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
800 serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
801 serial_out(up, UART_EFR, efr); /* Enable AUTORTS and AUTOCTS */
802 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
803 serial_out(up, UART_MCR, up->mcr | UART_MCR_RTS);
804 serial_out(up, UART_LCR, cval);
807 serial_omap_set_mctrl(&up->port, up->port.mctrl);
808 /* Software Flow Control Configuration */
809 if (termios->c_iflag & (IXON | IXOFF))
810 serial_omap_configure_xonxoff(up, termios);
812 spin_unlock_irqrestore(&up->port.lock, flags);
813 dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->pdev->id);
816 static void
817 serial_omap_pm(struct uart_port *port, unsigned int state,
818 unsigned int oldstate)
820 struct uart_omap_port *up = (struct uart_omap_port *)port;
821 unsigned char efr;
823 dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->pdev->id);
824 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
825 efr = serial_in(up, UART_EFR);
826 serial_out(up, UART_EFR, efr | UART_EFR_ECB);
827 serial_out(up, UART_LCR, 0);
829 serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
830 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
831 serial_out(up, UART_EFR, efr);
832 serial_out(up, UART_LCR, 0);
835 static void serial_omap_release_port(struct uart_port *port)
837 dev_dbg(port->dev, "serial_omap_release_port+\n");
840 static int serial_omap_request_port(struct uart_port *port)
842 dev_dbg(port->dev, "serial_omap_request_port+\n");
843 return 0;
846 static void serial_omap_config_port(struct uart_port *port, int flags)
848 struct uart_omap_port *up = (struct uart_omap_port *)port;
850 dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
851 up->pdev->id);
852 up->port.type = PORT_OMAP;
855 static int
856 serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
858 /* we don't want the core code to modify any port params */
859 dev_dbg(port->dev, "serial_omap_verify_port+\n");
860 return -EINVAL;
863 static const char *
864 serial_omap_type(struct uart_port *port)
866 struct uart_omap_port *up = (struct uart_omap_port *)port;
868 dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->pdev->id);
869 return up->name;
872 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
874 static inline void wait_for_xmitr(struct uart_omap_port *up)
876 unsigned int status, tmout = 10000;
878 /* Wait up to 10ms for the character(s) to be sent. */
879 do {
880 status = serial_in(up, UART_LSR);
882 if (status & UART_LSR_BI)
883 up->lsr_break_flag = UART_LSR_BI;
885 if (--tmout == 0)
886 break;
887 udelay(1);
888 } while ((status & BOTH_EMPTY) != BOTH_EMPTY);
890 /* Wait up to 1s for flow control if necessary */
891 if (up->port.flags & UPF_CONS_FLOW) {
892 tmout = 1000000;
893 for (tmout = 1000000; tmout; tmout--) {
894 unsigned int msr = serial_in(up, UART_MSR);
896 up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
897 if (msr & UART_MSR_CTS)
898 break;
900 udelay(1);
905 #ifdef CONFIG_CONSOLE_POLL
907 static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
909 struct uart_omap_port *up = (struct uart_omap_port *)port;
910 wait_for_xmitr(up);
911 serial_out(up, UART_TX, ch);
914 static int serial_omap_poll_get_char(struct uart_port *port)
916 struct uart_omap_port *up = (struct uart_omap_port *)port;
917 unsigned int status = serial_in(up, UART_LSR);
919 if (!(status & UART_LSR_DR))
920 return NO_POLL_CHAR;
922 return serial_in(up, UART_RX);
925 #endif /* CONFIG_CONSOLE_POLL */
927 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
929 static struct uart_omap_port *serial_omap_console_ports[4];
931 static struct uart_driver serial_omap_reg;
933 static void serial_omap_console_putchar(struct uart_port *port, int ch)
935 struct uart_omap_port *up = (struct uart_omap_port *)port;
937 wait_for_xmitr(up);
938 serial_out(up, UART_TX, ch);
941 static void
942 serial_omap_console_write(struct console *co, const char *s,
943 unsigned int count)
945 struct uart_omap_port *up = serial_omap_console_ports[co->index];
946 unsigned long flags;
947 unsigned int ier;
948 int locked = 1;
950 local_irq_save(flags);
951 if (up->port.sysrq)
952 locked = 0;
953 else if (oops_in_progress)
954 locked = spin_trylock(&up->port.lock);
955 else
956 spin_lock(&up->port.lock);
959 * First save the IER then disable the interrupts
961 ier = serial_in(up, UART_IER);
962 serial_out(up, UART_IER, 0);
964 uart_console_write(&up->port, s, count, serial_omap_console_putchar);
967 * Finally, wait for transmitter to become empty
968 * and restore the IER
970 wait_for_xmitr(up);
971 serial_out(up, UART_IER, ier);
973 * The receive handling will happen properly because the
974 * receive ready bit will still be set; it is not cleared
975 * on read. However, modem control will not, we must
976 * call it if we have saved something in the saved flags
977 * while processing with interrupts off.
979 if (up->msr_saved_flags)
980 check_modem_status(up);
982 if (locked)
983 spin_unlock(&up->port.lock);
984 local_irq_restore(flags);
987 static int __init
988 serial_omap_console_setup(struct console *co, char *options)
990 struct uart_omap_port *up;
991 int baud = 115200;
992 int bits = 8;
993 int parity = 'n';
994 int flow = 'n';
996 if (serial_omap_console_ports[co->index] == NULL)
997 return -ENODEV;
998 up = serial_omap_console_ports[co->index];
1000 if (options)
1001 uart_parse_options(options, &baud, &parity, &bits, &flow);
1003 return uart_set_options(&up->port, co, baud, parity, bits, flow);
1006 static struct console serial_omap_console = {
1007 .name = OMAP_SERIAL_NAME,
1008 .write = serial_omap_console_write,
1009 .device = uart_console_device,
1010 .setup = serial_omap_console_setup,
1011 .flags = CON_PRINTBUFFER,
1012 .index = -1,
1013 .data = &serial_omap_reg,
1016 static void serial_omap_add_console_port(struct uart_omap_port *up)
1018 serial_omap_console_ports[up->pdev->id] = up;
1021 #define OMAP_CONSOLE (&serial_omap_console)
1023 #else
1025 #define OMAP_CONSOLE NULL
1027 static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1030 #endif
1032 static struct uart_ops serial_omap_pops = {
1033 .tx_empty = serial_omap_tx_empty,
1034 .set_mctrl = serial_omap_set_mctrl,
1035 .get_mctrl = serial_omap_get_mctrl,
1036 .stop_tx = serial_omap_stop_tx,
1037 .start_tx = serial_omap_start_tx,
1038 .stop_rx = serial_omap_stop_rx,
1039 .enable_ms = serial_omap_enable_ms,
1040 .break_ctl = serial_omap_break_ctl,
1041 .startup = serial_omap_startup,
1042 .shutdown = serial_omap_shutdown,
1043 .set_termios = serial_omap_set_termios,
1044 .pm = serial_omap_pm,
1045 .type = serial_omap_type,
1046 .release_port = serial_omap_release_port,
1047 .request_port = serial_omap_request_port,
1048 .config_port = serial_omap_config_port,
1049 .verify_port = serial_omap_verify_port,
1050 #ifdef CONFIG_CONSOLE_POLL
1051 .poll_put_char = serial_omap_poll_put_char,
1052 .poll_get_char = serial_omap_poll_get_char,
1053 #endif
1056 static struct uart_driver serial_omap_reg = {
1057 .owner = THIS_MODULE,
1058 .driver_name = "OMAP-SERIAL",
1059 .dev_name = OMAP_SERIAL_NAME,
1060 .nr = OMAP_MAX_HSUART_PORTS,
1061 .cons = OMAP_CONSOLE,
1064 static int
1065 serial_omap_suspend(struct platform_device *pdev, pm_message_t state)
1067 struct uart_omap_port *up = platform_get_drvdata(pdev);
1069 if (up)
1070 uart_suspend_port(&serial_omap_reg, &up->port);
1071 return 0;
1074 static int serial_omap_resume(struct platform_device *dev)
1076 struct uart_omap_port *up = platform_get_drvdata(dev);
1078 if (up)
1079 uart_resume_port(&serial_omap_reg, &up->port);
1080 return 0;
1083 static void serial_omap_rx_timeout(unsigned long uart_no)
1085 struct uart_omap_port *up = ui[uart_no];
1086 unsigned int curr_dma_pos, curr_transmitted_size;
1087 int ret = 0;
1089 curr_dma_pos = omap_get_dma_dst_pos(up->uart_dma.rx_dma_channel);
1090 if ((curr_dma_pos == up->uart_dma.prev_rx_dma_pos) ||
1091 (curr_dma_pos == 0)) {
1092 if (jiffies_to_msecs(jiffies - up->port_activity) <
1093 RX_TIMEOUT) {
1094 mod_timer(&up->uart_dma.rx_timer, jiffies +
1095 usecs_to_jiffies(up->uart_dma.rx_timeout));
1096 } else {
1097 serial_omap_stop_rxdma(up);
1098 up->ier |= (UART_IER_RDI | UART_IER_RLSI);
1099 serial_out(up, UART_IER, up->ier);
1101 return;
1104 curr_transmitted_size = curr_dma_pos -
1105 up->uart_dma.prev_rx_dma_pos;
1106 up->port.icount.rx += curr_transmitted_size;
1107 tty_insert_flip_string(up->port.state->port.tty,
1108 up->uart_dma.rx_buf +
1109 (up->uart_dma.prev_rx_dma_pos -
1110 up->uart_dma.rx_buf_dma_phys),
1111 curr_transmitted_size);
1112 tty_flip_buffer_push(up->port.state->port.tty);
1113 up->uart_dma.prev_rx_dma_pos = curr_dma_pos;
1114 if (up->uart_dma.rx_buf_size +
1115 up->uart_dma.rx_buf_dma_phys == curr_dma_pos) {
1116 ret = serial_omap_start_rxdma(up);
1117 if (ret < 0) {
1118 serial_omap_stop_rxdma(up);
1119 up->ier |= (UART_IER_RDI | UART_IER_RLSI);
1120 serial_out(up, UART_IER, up->ier);
1122 } else {
1123 mod_timer(&up->uart_dma.rx_timer, jiffies +
1124 usecs_to_jiffies(up->uart_dma.rx_timeout));
1126 up->port_activity = jiffies;
1129 static void uart_rx_dma_callback(int lch, u16 ch_status, void *data)
1131 return;
1134 static int serial_omap_start_rxdma(struct uart_omap_port *up)
1136 int ret = 0;
1138 if (up->uart_dma.rx_dma_channel == -1) {
1139 ret = omap_request_dma(up->uart_dma.uart_dma_rx,
1140 "UART Rx DMA",
1141 (void *)uart_rx_dma_callback, up,
1142 &(up->uart_dma.rx_dma_channel));
1143 if (ret < 0)
1144 return ret;
1146 omap_set_dma_src_params(up->uart_dma.rx_dma_channel, 0,
1147 OMAP_DMA_AMODE_CONSTANT,
1148 up->uart_dma.uart_base, 0, 0);
1149 omap_set_dma_dest_params(up->uart_dma.rx_dma_channel, 0,
1150 OMAP_DMA_AMODE_POST_INC,
1151 up->uart_dma.rx_buf_dma_phys, 0, 0);
1152 omap_set_dma_transfer_params(up->uart_dma.rx_dma_channel,
1153 OMAP_DMA_DATA_TYPE_S8,
1154 up->uart_dma.rx_buf_size, 1,
1155 OMAP_DMA_SYNC_ELEMENT,
1156 up->uart_dma.uart_dma_rx, 0);
1158 up->uart_dma.prev_rx_dma_pos = up->uart_dma.rx_buf_dma_phys;
1159 /* FIXME: Cache maintenance needed here? */
1160 omap_start_dma(up->uart_dma.rx_dma_channel);
1161 mod_timer(&up->uart_dma.rx_timer, jiffies +
1162 usecs_to_jiffies(up->uart_dma.rx_timeout));
1163 up->uart_dma.rx_dma_used = true;
1164 return ret;
1167 static void serial_omap_continue_tx(struct uart_omap_port *up)
1169 struct circ_buf *xmit = &up->port.state->xmit;
1170 unsigned int start = up->uart_dma.tx_buf_dma_phys
1171 + (xmit->tail & (UART_XMIT_SIZE - 1));
1173 if (uart_circ_empty(xmit))
1174 return;
1176 up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
1178 * It is a circular buffer. See if the buffer has wounded back.
1179 * If yes it will have to be transferred in two separate dma
1180 * transfers
1182 if (start + up->uart_dma.tx_buf_size >=
1183 up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
1184 up->uart_dma.tx_buf_size =
1185 (up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE) - start;
1186 omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
1187 OMAP_DMA_AMODE_CONSTANT,
1188 up->uart_dma.uart_base, 0, 0);
1189 omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
1190 OMAP_DMA_AMODE_POST_INC, start, 0, 0);
1191 omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
1192 OMAP_DMA_DATA_TYPE_S8,
1193 up->uart_dma.tx_buf_size, 1,
1194 OMAP_DMA_SYNC_ELEMENT,
1195 up->uart_dma.uart_dma_tx, 0);
1196 /* FIXME: Cache maintenance needed here? */
1197 omap_start_dma(up->uart_dma.tx_dma_channel);
1200 static void uart_tx_dma_callback(int lch, u16 ch_status, void *data)
1202 struct uart_omap_port *up = (struct uart_omap_port *)data;
1203 struct circ_buf *xmit = &up->port.state->xmit;
1205 xmit->tail = (xmit->tail + up->uart_dma.tx_buf_size) & \
1206 (UART_XMIT_SIZE - 1);
1207 up->port.icount.tx += up->uart_dma.tx_buf_size;
1209 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1210 uart_write_wakeup(&up->port);
1212 if (uart_circ_empty(xmit)) {
1213 spin_lock(&(up->uart_dma.tx_lock));
1214 serial_omap_stop_tx(&up->port);
1215 up->uart_dma.tx_dma_used = false;
1216 spin_unlock(&(up->uart_dma.tx_lock));
1217 } else {
1218 omap_stop_dma(up->uart_dma.tx_dma_channel);
1219 serial_omap_continue_tx(up);
1221 up->port_activity = jiffies;
1222 return;
1225 static int serial_omap_probe(struct platform_device *pdev)
1227 struct uart_omap_port *up;
1228 struct resource *mem, *irq, *dma_tx, *dma_rx;
1229 struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data;
1230 int ret = -ENOSPC;
1232 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1233 if (!mem) {
1234 dev_err(&pdev->dev, "no mem resource?\n");
1235 return -ENODEV;
1238 irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1239 if (!irq) {
1240 dev_err(&pdev->dev, "no irq resource?\n");
1241 return -ENODEV;
1244 if (!request_mem_region(mem->start, (mem->end - mem->start) + 1,
1245 pdev->dev.driver->name)) {
1246 dev_err(&pdev->dev, "memory region already claimed\n");
1247 return -EBUSY;
1250 dma_rx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "rx");
1251 if (!dma_rx) {
1252 ret = -EINVAL;
1253 goto err;
1256 dma_tx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "tx");
1257 if (!dma_tx) {
1258 ret = -EINVAL;
1259 goto err;
1262 up = kzalloc(sizeof(*up), GFP_KERNEL);
1263 if (up == NULL) {
1264 ret = -ENOMEM;
1265 goto do_release_region;
1267 sprintf(up->name, "OMAP UART%d", pdev->id);
1268 up->pdev = pdev;
1269 up->port.dev = &pdev->dev;
1270 up->port.type = PORT_OMAP;
1271 up->port.iotype = UPIO_MEM;
1272 up->port.irq = irq->start;
1274 up->port.regshift = 2;
1275 up->port.fifosize = 64;
1276 up->port.ops = &serial_omap_pops;
1277 up->port.line = pdev->id;
1279 up->port.membase = omap_up_info->membase;
1280 up->port.mapbase = omap_up_info->mapbase;
1281 up->port.flags = omap_up_info->flags;
1282 up->port.irqflags = omap_up_info->irqflags;
1283 up->port.uartclk = omap_up_info->uartclk;
1284 up->uart_dma.uart_base = mem->start;
1286 if (omap_up_info->dma_enabled) {
1287 up->uart_dma.uart_dma_tx = dma_tx->start;
1288 up->uart_dma.uart_dma_rx = dma_rx->start;
1289 up->use_dma = 1;
1290 up->uart_dma.rx_buf_size = 4096;
1291 up->uart_dma.rx_timeout = 2;
1292 spin_lock_init(&(up->uart_dma.tx_lock));
1293 spin_lock_init(&(up->uart_dma.rx_lock));
1294 up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
1295 up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE;
1298 ui[pdev->id] = up;
1299 serial_omap_add_console_port(up);
1301 ret = uart_add_one_port(&serial_omap_reg, &up->port);
1302 if (ret != 0)
1303 goto do_release_region;
1305 platform_set_drvdata(pdev, up);
1306 return 0;
1307 err:
1308 dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n",
1309 pdev->id, __func__, ret);
1310 do_release_region:
1311 release_mem_region(mem->start, (mem->end - mem->start) + 1);
1312 return ret;
1315 static int serial_omap_remove(struct platform_device *dev)
1317 struct uart_omap_port *up = platform_get_drvdata(dev);
1319 platform_set_drvdata(dev, NULL);
1320 if (up) {
1321 uart_remove_one_port(&serial_omap_reg, &up->port);
1322 kfree(up);
1324 return 0;
1327 static struct platform_driver serial_omap_driver = {
1328 .probe = serial_omap_probe,
1329 .remove = serial_omap_remove,
1331 .suspend = serial_omap_suspend,
1332 .resume = serial_omap_resume,
1333 .driver = {
1334 .name = DRIVER_NAME,
1338 static int __init serial_omap_init(void)
1340 int ret;
1342 ret = uart_register_driver(&serial_omap_reg);
1343 if (ret != 0)
1344 return ret;
1345 ret = platform_driver_register(&serial_omap_driver);
1346 if (ret != 0)
1347 uart_unregister_driver(&serial_omap_reg);
1348 return ret;
1351 static void __exit serial_omap_exit(void)
1353 platform_driver_unregister(&serial_omap_driver);
1354 uart_unregister_driver(&serial_omap_reg);
1357 module_init(serial_omap_init);
1358 module_exit(serial_omap_exit);
1360 MODULE_DESCRIPTION("OMAP High Speed UART driver");
1361 MODULE_LICENSE("GPL");
1362 MODULE_AUTHOR("Texas Instruments Inc");