Merge branch 'slabh' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / serial / imx.c
blob4315b23590bd9895ae867f9020446b33b8aae407
1 /*
2 * linux/drivers/serial/imx.c
4 * Driver for Motorola IMX serial ports
6 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
8 * Author: Sascha Hauer <sascha@saschahauer.de>
9 * Copyright (C) 2004 Pengutronix
11 * Copyright (C) 2009 emlix GmbH
12 * Author: Fabian Godehardt (added IrDA support for iMX)
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, write to the Free Software
26 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
28 * [29-Mar-2005] Mike Lee
29 * Added hardware handshake
32 #if defined(CONFIG_SERIAL_IMX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
33 #define SUPPORT_SYSRQ
34 #endif
36 #include <linux/module.h>
37 #include <linux/ioport.h>
38 #include <linux/init.h>
39 #include <linux/console.h>
40 #include <linux/sysrq.h>
41 #include <linux/platform_device.h>
42 #include <linux/tty.h>
43 #include <linux/tty_flip.h>
44 #include <linux/serial_core.h>
45 #include <linux/serial.h>
46 #include <linux/clk.h>
47 #include <linux/delay.h>
48 #include <linux/rational.h>
49 #include <linux/slab.h>
51 #include <asm/io.h>
52 #include <asm/irq.h>
53 #include <mach/hardware.h>
54 #include <mach/imx-uart.h>
56 /* Register definitions */
57 #define URXD0 0x0 /* Receiver Register */
58 #define URTX0 0x40 /* Transmitter Register */
59 #define UCR1 0x80 /* Control Register 1 */
60 #define UCR2 0x84 /* Control Register 2 */
61 #define UCR3 0x88 /* Control Register 3 */
62 #define UCR4 0x8c /* Control Register 4 */
63 #define UFCR 0x90 /* FIFO Control Register */
64 #define USR1 0x94 /* Status Register 1 */
65 #define USR2 0x98 /* Status Register 2 */
66 #define UESC 0x9c /* Escape Character Register */
67 #define UTIM 0xa0 /* Escape Timer Register */
68 #define UBIR 0xa4 /* BRM Incremental Register */
69 #define UBMR 0xa8 /* BRM Modulator Register */
70 #define UBRC 0xac /* Baud Rate Count Register */
71 #define MX2_ONEMS 0xb0 /* One Millisecond register */
72 #define UTS (cpu_is_mx1() ? 0xd0 : 0xb4) /* UART Test Register */
74 /* UART Control Register Bit Fields.*/
75 #define URXD_CHARRDY (1<<15)
76 #define URXD_ERR (1<<14)
77 #define URXD_OVRRUN (1<<13)
78 #define URXD_FRMERR (1<<12)
79 #define URXD_BRK (1<<11)
80 #define URXD_PRERR (1<<10)
81 #define UCR1_ADEN (1<<15) /* Auto dectect interrupt */
82 #define UCR1_ADBR (1<<14) /* Auto detect baud rate */
83 #define UCR1_TRDYEN (1<<13) /* Transmitter ready interrupt enable */
84 #define UCR1_IDEN (1<<12) /* Idle condition interrupt */
85 #define UCR1_RRDYEN (1<<9) /* Recv ready interrupt enable */
86 #define UCR1_RDMAEN (1<<8) /* Recv ready DMA enable */
87 #define UCR1_IREN (1<<7) /* Infrared interface enable */
88 #define UCR1_TXMPTYEN (1<<6) /* Transimitter empty interrupt enable */
89 #define UCR1_RTSDEN (1<<5) /* RTS delta interrupt enable */
90 #define UCR1_SNDBRK (1<<4) /* Send break */
91 #define UCR1_TDMAEN (1<<3) /* Transmitter ready DMA enable */
92 #define MX1_UCR1_UARTCLKEN (1<<2) /* UART clock enabled, mx1 only */
93 #define UCR1_DOZE (1<<1) /* Doze */
94 #define UCR1_UARTEN (1<<0) /* UART enabled */
95 #define UCR2_ESCI (1<<15) /* Escape seq interrupt enable */
96 #define UCR2_IRTS (1<<14) /* Ignore RTS pin */
97 #define UCR2_CTSC (1<<13) /* CTS pin control */
98 #define UCR2_CTS (1<<12) /* Clear to send */
99 #define UCR2_ESCEN (1<<11) /* Escape enable */
100 #define UCR2_PREN (1<<8) /* Parity enable */
101 #define UCR2_PROE (1<<7) /* Parity odd/even */
102 #define UCR2_STPB (1<<6) /* Stop */
103 #define UCR2_WS (1<<5) /* Word size */
104 #define UCR2_RTSEN (1<<4) /* Request to send interrupt enable */
105 #define UCR2_TXEN (1<<2) /* Transmitter enabled */
106 #define UCR2_RXEN (1<<1) /* Receiver enabled */
107 #define UCR2_SRST (1<<0) /* SW reset */
108 #define UCR3_DTREN (1<<13) /* DTR interrupt enable */
109 #define UCR3_PARERREN (1<<12) /* Parity enable */
110 #define UCR3_FRAERREN (1<<11) /* Frame error interrupt enable */
111 #define UCR3_DSR (1<<10) /* Data set ready */
112 #define UCR3_DCD (1<<9) /* Data carrier detect */
113 #define UCR3_RI (1<<8) /* Ring indicator */
114 #define UCR3_TIMEOUTEN (1<<7) /* Timeout interrupt enable */
115 #define UCR3_RXDSEN (1<<6) /* Receive status interrupt enable */
116 #define UCR3_AIRINTEN (1<<5) /* Async IR wake interrupt enable */
117 #define UCR3_AWAKEN (1<<4) /* Async wake interrupt enable */
118 #define MX1_UCR3_REF25 (1<<3) /* Ref freq 25 MHz, only on mx1 */
119 #define MX1_UCR3_REF30 (1<<2) /* Ref Freq 30 MHz, only on mx1 */
120 #define MX2_UCR3_RXDMUXSEL (1<<2) /* RXD Muxed Input Select, on mx2/mx3 */
121 #define UCR3_INVT (1<<1) /* Inverted Infrared transmission */
122 #define UCR3_BPEN (1<<0) /* Preset registers enable */
123 #define UCR4_CTSTL_32 (32<<10) /* CTS trigger level (32 chars) */
124 #define UCR4_INVR (1<<9) /* Inverted infrared reception */
125 #define UCR4_ENIRI (1<<8) /* Serial infrared interrupt enable */
126 #define UCR4_WKEN (1<<7) /* Wake interrupt enable */
127 #define UCR4_REF16 (1<<6) /* Ref freq 16 MHz */
128 #define UCR4_IRSC (1<<5) /* IR special case */
129 #define UCR4_TCEN (1<<3) /* Transmit complete interrupt enable */
130 #define UCR4_BKEN (1<<2) /* Break condition interrupt enable */
131 #define UCR4_OREN (1<<1) /* Receiver overrun interrupt enable */
132 #define UCR4_DREN (1<<0) /* Recv data ready interrupt enable */
133 #define UFCR_RXTL_SHF 0 /* Receiver trigger level shift */
134 #define UFCR_RFDIV (7<<7) /* Reference freq divider mask */
135 #define UFCR_RFDIV_REG(x) (((x) < 7 ? 6 - (x) : 6) << 7)
136 #define UFCR_TXTL_SHF 10 /* Transmitter trigger level shift */
137 #define USR1_PARITYERR (1<<15) /* Parity error interrupt flag */
138 #define USR1_RTSS (1<<14) /* RTS pin status */
139 #define USR1_TRDY (1<<13) /* Transmitter ready interrupt/dma flag */
140 #define USR1_RTSD (1<<12) /* RTS delta */
141 #define USR1_ESCF (1<<11) /* Escape seq interrupt flag */
142 #define USR1_FRAMERR (1<<10) /* Frame error interrupt flag */
143 #define USR1_RRDY (1<<9) /* Receiver ready interrupt/dma flag */
144 #define USR1_TIMEOUT (1<<7) /* Receive timeout interrupt status */
145 #define USR1_RXDS (1<<6) /* Receiver idle interrupt flag */
146 #define USR1_AIRINT (1<<5) /* Async IR wake interrupt flag */
147 #define USR1_AWAKE (1<<4) /* Aysnc wake interrupt flag */
148 #define USR2_ADET (1<<15) /* Auto baud rate detect complete */
149 #define USR2_TXFE (1<<14) /* Transmit buffer FIFO empty */
150 #define USR2_DTRF (1<<13) /* DTR edge interrupt flag */
151 #define USR2_IDLE (1<<12) /* Idle condition */
152 #define USR2_IRINT (1<<8) /* Serial infrared interrupt flag */
153 #define USR2_WAKE (1<<7) /* Wake */
154 #define USR2_RTSF (1<<4) /* RTS edge interrupt flag */
155 #define USR2_TXDC (1<<3) /* Transmitter complete */
156 #define USR2_BRCD (1<<2) /* Break condition */
157 #define USR2_ORE (1<<1) /* Overrun error */
158 #define USR2_RDR (1<<0) /* Recv data ready */
159 #define UTS_FRCPERR (1<<13) /* Force parity error */
160 #define UTS_LOOP (1<<12) /* Loop tx and rx */
161 #define UTS_TXEMPTY (1<<6) /* TxFIFO empty */
162 #define UTS_RXEMPTY (1<<5) /* RxFIFO empty */
163 #define UTS_TXFULL (1<<4) /* TxFIFO full */
164 #define UTS_RXFULL (1<<3) /* RxFIFO full */
165 #define UTS_SOFTRST (1<<0) /* Software reset */
167 /* We've been assigned a range on the "Low-density serial ports" major */
168 #define SERIAL_IMX_MAJOR 207
169 #define MINOR_START 16
170 #define DEV_NAME "ttymxc"
171 #define MAX_INTERNAL_IRQ MXC_INTERNAL_IRQS
174 * This determines how often we check the modem status signals
175 * for any change. They generally aren't connected to an IRQ
176 * so we have to poll them. We also check immediately before
177 * filling the TX fifo incase CTS has been dropped.
179 #define MCTRL_TIMEOUT (250*HZ/1000)
181 #define DRIVER_NAME "IMX-uart"
183 #define UART_NR 8
185 struct imx_port {
186 struct uart_port port;
187 struct timer_list timer;
188 unsigned int old_status;
189 int txirq,rxirq,rtsirq;
190 unsigned int have_rtscts:1;
191 unsigned int use_irda:1;
192 unsigned int irda_inv_rx:1;
193 unsigned int irda_inv_tx:1;
194 unsigned short trcv_delay; /* transceiver delay */
195 struct clk *clk;
198 #ifdef CONFIG_IRDA
199 #define USE_IRDA(sport) ((sport)->use_irda)
200 #else
201 #define USE_IRDA(sport) (0)
202 #endif
205 * Handle any change of modem status signal since we were last called.
207 static void imx_mctrl_check(struct imx_port *sport)
209 unsigned int status, changed;
211 status = sport->port.ops->get_mctrl(&sport->port);
212 changed = status ^ sport->old_status;
214 if (changed == 0)
215 return;
217 sport->old_status = status;
219 if (changed & TIOCM_RI)
220 sport->port.icount.rng++;
221 if (changed & TIOCM_DSR)
222 sport->port.icount.dsr++;
223 if (changed & TIOCM_CAR)
224 uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
225 if (changed & TIOCM_CTS)
226 uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
228 wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
232 * This is our per-port timeout handler, for checking the
233 * modem status signals.
235 static void imx_timeout(unsigned long data)
237 struct imx_port *sport = (struct imx_port *)data;
238 unsigned long flags;
240 if (sport->port.state) {
241 spin_lock_irqsave(&sport->port.lock, flags);
242 imx_mctrl_check(sport);
243 spin_unlock_irqrestore(&sport->port.lock, flags);
245 mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
250 * interrupts disabled on entry
252 static void imx_stop_tx(struct uart_port *port)
254 struct imx_port *sport = (struct imx_port *)port;
255 unsigned long temp;
257 if (USE_IRDA(sport)) {
258 /* half duplex - wait for end of transmission */
259 int n = 256;
260 while ((--n > 0) &&
261 !(readl(sport->port.membase + USR2) & USR2_TXDC)) {
262 udelay(5);
263 barrier();
266 * irda transceiver - wait a bit more to avoid
267 * cutoff, hardware dependent
269 udelay(sport->trcv_delay);
272 * half duplex - reactivate receive mode,
273 * flush receive pipe echo crap
275 if (readl(sport->port.membase + USR2) & USR2_TXDC) {
276 temp = readl(sport->port.membase + UCR1);
277 temp &= ~(UCR1_TXMPTYEN | UCR1_TRDYEN);
278 writel(temp, sport->port.membase + UCR1);
280 temp = readl(sport->port.membase + UCR4);
281 temp &= ~(UCR4_TCEN);
282 writel(temp, sport->port.membase + UCR4);
284 while (readl(sport->port.membase + URXD0) &
285 URXD_CHARRDY)
286 barrier();
288 temp = readl(sport->port.membase + UCR1);
289 temp |= UCR1_RRDYEN;
290 writel(temp, sport->port.membase + UCR1);
292 temp = readl(sport->port.membase + UCR4);
293 temp |= UCR4_DREN;
294 writel(temp, sport->port.membase + UCR4);
296 return;
299 temp = readl(sport->port.membase + UCR1);
300 writel(temp & ~UCR1_TXMPTYEN, sport->port.membase + UCR1);
304 * interrupts disabled on entry
306 static void imx_stop_rx(struct uart_port *port)
308 struct imx_port *sport = (struct imx_port *)port;
309 unsigned long temp;
311 temp = readl(sport->port.membase + UCR2);
312 writel(temp &~ UCR2_RXEN, sport->port.membase + UCR2);
316 * Set the modem control timer to fire immediately.
318 static void imx_enable_ms(struct uart_port *port)
320 struct imx_port *sport = (struct imx_port *)port;
322 mod_timer(&sport->timer, jiffies);
325 static inline void imx_transmit_buffer(struct imx_port *sport)
327 struct circ_buf *xmit = &sport->port.state->xmit;
329 while (!(readl(sport->port.membase + UTS) & UTS_TXFULL)) {
330 /* send xmit->buf[xmit->tail]
331 * out the port here */
332 writel(xmit->buf[xmit->tail], sport->port.membase + URTX0);
333 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
334 sport->port.icount.tx++;
335 if (uart_circ_empty(xmit))
336 break;
339 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
340 uart_write_wakeup(&sport->port);
342 if (uart_circ_empty(xmit))
343 imx_stop_tx(&sport->port);
347 * interrupts disabled on entry
349 static void imx_start_tx(struct uart_port *port)
351 struct imx_port *sport = (struct imx_port *)port;
352 unsigned long temp;
354 if (USE_IRDA(sport)) {
355 /* half duplex in IrDA mode; have to disable receive mode */
356 temp = readl(sport->port.membase + UCR4);
357 temp &= ~(UCR4_DREN);
358 writel(temp, sport->port.membase + UCR4);
360 temp = readl(sport->port.membase + UCR1);
361 temp &= ~(UCR1_RRDYEN);
362 writel(temp, sport->port.membase + UCR1);
365 temp = readl(sport->port.membase + UCR1);
366 writel(temp | UCR1_TXMPTYEN, sport->port.membase + UCR1);
368 if (USE_IRDA(sport)) {
369 temp = readl(sport->port.membase + UCR1);
370 temp |= UCR1_TRDYEN;
371 writel(temp, sport->port.membase + UCR1);
373 temp = readl(sport->port.membase + UCR4);
374 temp |= UCR4_TCEN;
375 writel(temp, sport->port.membase + UCR4);
378 if (readl(sport->port.membase + UTS) & UTS_TXEMPTY)
379 imx_transmit_buffer(sport);
382 static irqreturn_t imx_rtsint(int irq, void *dev_id)
384 struct imx_port *sport = dev_id;
385 unsigned int val = readl(sport->port.membase + USR1) & USR1_RTSS;
386 unsigned long flags;
388 spin_lock_irqsave(&sport->port.lock, flags);
390 writel(USR1_RTSD, sport->port.membase + USR1);
391 uart_handle_cts_change(&sport->port, !!val);
392 wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
394 spin_unlock_irqrestore(&sport->port.lock, flags);
395 return IRQ_HANDLED;
398 static irqreturn_t imx_txint(int irq, void *dev_id)
400 struct imx_port *sport = dev_id;
401 struct circ_buf *xmit = &sport->port.state->xmit;
402 unsigned long flags;
404 spin_lock_irqsave(&sport->port.lock,flags);
405 if (sport->port.x_char)
407 /* Send next char */
408 writel(sport->port.x_char, sport->port.membase + URTX0);
409 goto out;
412 if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
413 imx_stop_tx(&sport->port);
414 goto out;
417 imx_transmit_buffer(sport);
419 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
420 uart_write_wakeup(&sport->port);
422 out:
423 spin_unlock_irqrestore(&sport->port.lock,flags);
424 return IRQ_HANDLED;
427 static irqreturn_t imx_rxint(int irq, void *dev_id)
429 struct imx_port *sport = dev_id;
430 unsigned int rx,flg,ignored = 0;
431 struct tty_struct *tty = sport->port.state->port.tty;
432 unsigned long flags, temp;
434 spin_lock_irqsave(&sport->port.lock,flags);
436 while (readl(sport->port.membase + USR2) & USR2_RDR) {
437 flg = TTY_NORMAL;
438 sport->port.icount.rx++;
440 rx = readl(sport->port.membase + URXD0);
442 temp = readl(sport->port.membase + USR2);
443 if (temp & USR2_BRCD) {
444 writel(USR2_BRCD, sport->port.membase + USR2);
445 if (uart_handle_break(&sport->port))
446 continue;
449 if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx))
450 continue;
452 if (rx & (URXD_PRERR | URXD_OVRRUN | URXD_FRMERR) ) {
453 if (rx & URXD_PRERR)
454 sport->port.icount.parity++;
455 else if (rx & URXD_FRMERR)
456 sport->port.icount.frame++;
457 if (rx & URXD_OVRRUN)
458 sport->port.icount.overrun++;
460 if (rx & sport->port.ignore_status_mask) {
461 if (++ignored > 100)
462 goto out;
463 continue;
466 rx &= sport->port.read_status_mask;
468 if (rx & URXD_PRERR)
469 flg = TTY_PARITY;
470 else if (rx & URXD_FRMERR)
471 flg = TTY_FRAME;
472 if (rx & URXD_OVRRUN)
473 flg = TTY_OVERRUN;
475 #ifdef SUPPORT_SYSRQ
476 sport->port.sysrq = 0;
477 #endif
480 tty_insert_flip_char(tty, rx, flg);
483 out:
484 spin_unlock_irqrestore(&sport->port.lock,flags);
485 tty_flip_buffer_push(tty);
486 return IRQ_HANDLED;
489 static irqreturn_t imx_int(int irq, void *dev_id)
491 struct imx_port *sport = dev_id;
492 unsigned int sts;
494 sts = readl(sport->port.membase + USR1);
496 if (sts & USR1_RRDY)
497 imx_rxint(irq, dev_id);
499 if (sts & USR1_TRDY &&
500 readl(sport->port.membase + UCR1) & UCR1_TXMPTYEN)
501 imx_txint(irq, dev_id);
503 if (sts & USR1_RTSD)
504 imx_rtsint(irq, dev_id);
506 return IRQ_HANDLED;
510 * Return TIOCSER_TEMT when transmitter is not busy.
512 static unsigned int imx_tx_empty(struct uart_port *port)
514 struct imx_port *sport = (struct imx_port *)port;
516 return (readl(sport->port.membase + USR2) & USR2_TXDC) ? TIOCSER_TEMT : 0;
520 * We have a modem side uart, so the meanings of RTS and CTS are inverted.
522 static unsigned int imx_get_mctrl(struct uart_port *port)
524 struct imx_port *sport = (struct imx_port *)port;
525 unsigned int tmp = TIOCM_DSR | TIOCM_CAR;
527 if (readl(sport->port.membase + USR1) & USR1_RTSS)
528 tmp |= TIOCM_CTS;
530 if (readl(sport->port.membase + UCR2) & UCR2_CTS)
531 tmp |= TIOCM_RTS;
533 return tmp;
536 static void imx_set_mctrl(struct uart_port *port, unsigned int mctrl)
538 struct imx_port *sport = (struct imx_port *)port;
539 unsigned long temp;
541 temp = readl(sport->port.membase + UCR2) & ~UCR2_CTS;
543 if (mctrl & TIOCM_RTS)
544 temp |= UCR2_CTS;
546 writel(temp, sport->port.membase + UCR2);
550 * Interrupts always disabled.
552 static void imx_break_ctl(struct uart_port *port, int break_state)
554 struct imx_port *sport = (struct imx_port *)port;
555 unsigned long flags, temp;
557 spin_lock_irqsave(&sport->port.lock, flags);
559 temp = readl(sport->port.membase + UCR1) & ~UCR1_SNDBRK;
561 if ( break_state != 0 )
562 temp |= UCR1_SNDBRK;
564 writel(temp, sport->port.membase + UCR1);
566 spin_unlock_irqrestore(&sport->port.lock, flags);
569 #define TXTL 2 /* reset default */
570 #define RXTL 1 /* reset default */
572 static int imx_setup_ufcr(struct imx_port *sport, unsigned int mode)
574 unsigned int val;
575 unsigned int ufcr_rfdiv;
577 /* set receiver / transmitter trigger level.
578 * RFDIV is set such way to satisfy requested uartclk value
580 val = TXTL << 10 | RXTL;
581 ufcr_rfdiv = (clk_get_rate(sport->clk) + sport->port.uartclk / 2)
582 / sport->port.uartclk;
584 if(!ufcr_rfdiv)
585 ufcr_rfdiv = 1;
587 val |= UFCR_RFDIV_REG(ufcr_rfdiv);
589 writel(val, sport->port.membase + UFCR);
591 return 0;
594 static int imx_startup(struct uart_port *port)
596 struct imx_port *sport = (struct imx_port *)port;
597 int retval;
598 unsigned long flags, temp;
600 imx_setup_ufcr(sport, 0);
602 /* disable the DREN bit (Data Ready interrupt enable) before
603 * requesting IRQs
605 temp = readl(sport->port.membase + UCR4);
607 if (USE_IRDA(sport))
608 temp |= UCR4_IRSC;
610 writel(temp & ~UCR4_DREN, sport->port.membase + UCR4);
612 if (USE_IRDA(sport)) {
613 /* reset fifo's and state machines */
614 int i = 100;
615 temp = readl(sport->port.membase + UCR2);
616 temp &= ~UCR2_SRST;
617 writel(temp, sport->port.membase + UCR2);
618 while (!(readl(sport->port.membase + UCR2) & UCR2_SRST) &&
619 (--i > 0)) {
620 udelay(1);
625 * Allocate the IRQ(s) i.MX1 has three interrupts whereas later
626 * chips only have one interrupt.
628 if (sport->txirq > 0) {
629 retval = request_irq(sport->rxirq, imx_rxint, 0,
630 DRIVER_NAME, sport);
631 if (retval)
632 goto error_out1;
634 retval = request_irq(sport->txirq, imx_txint, 0,
635 DRIVER_NAME, sport);
636 if (retval)
637 goto error_out2;
639 /* do not use RTS IRQ on IrDA */
640 if (!USE_IRDA(sport)) {
641 retval = request_irq(sport->rtsirq, imx_rtsint,
642 (sport->rtsirq < MAX_INTERNAL_IRQ) ? 0 :
643 IRQF_TRIGGER_FALLING |
644 IRQF_TRIGGER_RISING,
645 DRIVER_NAME, sport);
646 if (retval)
647 goto error_out3;
649 } else {
650 retval = request_irq(sport->port.irq, imx_int, 0,
651 DRIVER_NAME, sport);
652 if (retval) {
653 free_irq(sport->port.irq, sport);
654 goto error_out1;
659 * Finally, clear and enable interrupts
661 writel(USR1_RTSD, sport->port.membase + USR1);
663 temp = readl(sport->port.membase + UCR1);
664 temp |= UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN;
666 if (USE_IRDA(sport)) {
667 temp |= UCR1_IREN;
668 temp &= ~(UCR1_RTSDEN);
671 writel(temp, sport->port.membase + UCR1);
673 temp = readl(sport->port.membase + UCR2);
674 temp |= (UCR2_RXEN | UCR2_TXEN);
675 writel(temp, sport->port.membase + UCR2);
677 if (USE_IRDA(sport)) {
678 /* clear RX-FIFO */
679 int i = 64;
680 while ((--i > 0) &&
681 (readl(sport->port.membase + URXD0) & URXD_CHARRDY)) {
682 barrier();
686 if (!cpu_is_mx1()) {
687 temp = readl(sport->port.membase + UCR3);
688 temp |= MX2_UCR3_RXDMUXSEL;
689 writel(temp, sport->port.membase + UCR3);
692 if (USE_IRDA(sport)) {
693 temp = readl(sport->port.membase + UCR4);
694 if (sport->irda_inv_rx)
695 temp |= UCR4_INVR;
696 else
697 temp &= ~(UCR4_INVR);
698 writel(temp | UCR4_DREN, sport->port.membase + UCR4);
700 temp = readl(sport->port.membase + UCR3);
701 if (sport->irda_inv_tx)
702 temp |= UCR3_INVT;
703 else
704 temp &= ~(UCR3_INVT);
705 writel(temp, sport->port.membase + UCR3);
709 * Enable modem status interrupts
711 spin_lock_irqsave(&sport->port.lock,flags);
712 imx_enable_ms(&sport->port);
713 spin_unlock_irqrestore(&sport->port.lock,flags);
715 if (USE_IRDA(sport)) {
716 struct imxuart_platform_data *pdata;
717 pdata = sport->port.dev->platform_data;
718 sport->irda_inv_rx = pdata->irda_inv_rx;
719 sport->irda_inv_tx = pdata->irda_inv_tx;
720 sport->trcv_delay = pdata->transceiver_delay;
721 if (pdata->irda_enable)
722 pdata->irda_enable(1);
725 return 0;
727 error_out3:
728 if (sport->txirq)
729 free_irq(sport->txirq, sport);
730 error_out2:
731 if (sport->rxirq)
732 free_irq(sport->rxirq, sport);
733 error_out1:
734 return retval;
737 static void imx_shutdown(struct uart_port *port)
739 struct imx_port *sport = (struct imx_port *)port;
740 unsigned long temp;
742 temp = readl(sport->port.membase + UCR2);
743 temp &= ~(UCR2_TXEN);
744 writel(temp, sport->port.membase + UCR2);
746 if (USE_IRDA(sport)) {
747 struct imxuart_platform_data *pdata;
748 pdata = sport->port.dev->platform_data;
749 if (pdata->irda_enable)
750 pdata->irda_enable(0);
754 * Stop our timer.
756 del_timer_sync(&sport->timer);
759 * Free the interrupts
761 if (sport->txirq > 0) {
762 if (!USE_IRDA(sport))
763 free_irq(sport->rtsirq, sport);
764 free_irq(sport->txirq, sport);
765 free_irq(sport->rxirq, sport);
766 } else
767 free_irq(sport->port.irq, sport);
770 * Disable all interrupts, port and break condition.
773 temp = readl(sport->port.membase + UCR1);
774 temp &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN);
775 if (USE_IRDA(sport))
776 temp &= ~(UCR1_IREN);
778 writel(temp, sport->port.membase + UCR1);
781 static void
782 imx_set_termios(struct uart_port *port, struct ktermios *termios,
783 struct ktermios *old)
785 struct imx_port *sport = (struct imx_port *)port;
786 unsigned long flags;
787 unsigned int ucr2, old_ucr1, old_txrxen, baud, quot;
788 unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
789 unsigned int div, ufcr;
790 unsigned long num, denom;
791 uint64_t tdiv64;
794 * If we don't support modem control lines, don't allow
795 * these to be set.
797 if (0) {
798 termios->c_cflag &= ~(HUPCL | CRTSCTS | CMSPAR);
799 termios->c_cflag |= CLOCAL;
803 * We only support CS7 and CS8.
805 while ((termios->c_cflag & CSIZE) != CS7 &&
806 (termios->c_cflag & CSIZE) != CS8) {
807 termios->c_cflag &= ~CSIZE;
808 termios->c_cflag |= old_csize;
809 old_csize = CS8;
812 if ((termios->c_cflag & CSIZE) == CS8)
813 ucr2 = UCR2_WS | UCR2_SRST | UCR2_IRTS;
814 else
815 ucr2 = UCR2_SRST | UCR2_IRTS;
817 if (termios->c_cflag & CRTSCTS) {
818 if( sport->have_rtscts ) {
819 ucr2 &= ~UCR2_IRTS;
820 ucr2 |= UCR2_CTSC;
821 } else {
822 termios->c_cflag &= ~CRTSCTS;
826 if (termios->c_cflag & CSTOPB)
827 ucr2 |= UCR2_STPB;
828 if (termios->c_cflag & PARENB) {
829 ucr2 |= UCR2_PREN;
830 if (termios->c_cflag & PARODD)
831 ucr2 |= UCR2_PROE;
835 * Ask the core to calculate the divisor for us.
837 baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
838 quot = uart_get_divisor(port, baud);
840 spin_lock_irqsave(&sport->port.lock, flags);
842 sport->port.read_status_mask = 0;
843 if (termios->c_iflag & INPCK)
844 sport->port.read_status_mask |= (URXD_FRMERR | URXD_PRERR);
845 if (termios->c_iflag & (BRKINT | PARMRK))
846 sport->port.read_status_mask |= URXD_BRK;
849 * Characters to ignore
851 sport->port.ignore_status_mask = 0;
852 if (termios->c_iflag & IGNPAR)
853 sport->port.ignore_status_mask |= URXD_PRERR;
854 if (termios->c_iflag & IGNBRK) {
855 sport->port.ignore_status_mask |= URXD_BRK;
857 * If we're ignoring parity and break indicators,
858 * ignore overruns too (for real raw support).
860 if (termios->c_iflag & IGNPAR)
861 sport->port.ignore_status_mask |= URXD_OVRRUN;
864 del_timer_sync(&sport->timer);
867 * Update the per-port timeout.
869 uart_update_timeout(port, termios->c_cflag, baud);
872 * disable interrupts and drain transmitter
874 old_ucr1 = readl(sport->port.membase + UCR1);
875 writel(old_ucr1 & ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN),
876 sport->port.membase + UCR1);
878 while ( !(readl(sport->port.membase + USR2) & USR2_TXDC))
879 barrier();
881 /* then, disable everything */
882 old_txrxen = readl(sport->port.membase + UCR2);
883 writel(old_txrxen & ~( UCR2_TXEN | UCR2_RXEN),
884 sport->port.membase + UCR2);
885 old_txrxen &= (UCR2_TXEN | UCR2_RXEN);
887 if (USE_IRDA(sport)) {
889 * use maximum available submodule frequency to
890 * avoid missing short pulses due to low sampling rate
892 div = 1;
893 } else {
894 div = sport->port.uartclk / (baud * 16);
895 if (div > 7)
896 div = 7;
897 if (!div)
898 div = 1;
901 rational_best_approximation(16 * div * baud, sport->port.uartclk,
902 1 << 16, 1 << 16, &num, &denom);
904 if (port->state && port->state->port.tty) {
905 tdiv64 = sport->port.uartclk;
906 tdiv64 *= num;
907 do_div(tdiv64, denom * 16 * div);
908 tty_encode_baud_rate(sport->port.state->port.tty,
909 (speed_t)tdiv64, (speed_t)tdiv64);
912 num -= 1;
913 denom -= 1;
915 ufcr = readl(sport->port.membase + UFCR);
916 ufcr = (ufcr & (~UFCR_RFDIV)) | UFCR_RFDIV_REG(div);
917 writel(ufcr, sport->port.membase + UFCR);
919 writel(num, sport->port.membase + UBIR);
920 writel(denom, sport->port.membase + UBMR);
922 if (!cpu_is_mx1())
923 writel(sport->port.uartclk / div / 1000,
924 sport->port.membase + MX2_ONEMS);
926 writel(old_ucr1, sport->port.membase + UCR1);
928 /* set the parity, stop bits and data size */
929 writel(ucr2 | old_txrxen, sport->port.membase + UCR2);
931 if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
932 imx_enable_ms(&sport->port);
934 spin_unlock_irqrestore(&sport->port.lock, flags);
937 static const char *imx_type(struct uart_port *port)
939 struct imx_port *sport = (struct imx_port *)port;
941 return sport->port.type == PORT_IMX ? "IMX" : NULL;
945 * Release the memory region(s) being used by 'port'.
947 static void imx_release_port(struct uart_port *port)
949 struct platform_device *pdev = to_platform_device(port->dev);
950 struct resource *mmres;
952 mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
953 release_mem_region(mmres->start, mmres->end - mmres->start + 1);
957 * Request the memory region(s) being used by 'port'.
959 static int imx_request_port(struct uart_port *port)
961 struct platform_device *pdev = to_platform_device(port->dev);
962 struct resource *mmres;
963 void *ret;
965 mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
966 if (!mmres)
967 return -ENODEV;
969 ret = request_mem_region(mmres->start, mmres->end - mmres->start + 1,
970 "imx-uart");
972 return ret ? 0 : -EBUSY;
976 * Configure/autoconfigure the port.
978 static void imx_config_port(struct uart_port *port, int flags)
980 struct imx_port *sport = (struct imx_port *)port;
982 if (flags & UART_CONFIG_TYPE &&
983 imx_request_port(&sport->port) == 0)
984 sport->port.type = PORT_IMX;
988 * Verify the new serial_struct (for TIOCSSERIAL).
989 * The only change we allow are to the flags and type, and
990 * even then only between PORT_IMX and PORT_UNKNOWN
992 static int
993 imx_verify_port(struct uart_port *port, struct serial_struct *ser)
995 struct imx_port *sport = (struct imx_port *)port;
996 int ret = 0;
998 if (ser->type != PORT_UNKNOWN && ser->type != PORT_IMX)
999 ret = -EINVAL;
1000 if (sport->port.irq != ser->irq)
1001 ret = -EINVAL;
1002 if (ser->io_type != UPIO_MEM)
1003 ret = -EINVAL;
1004 if (sport->port.uartclk / 16 != ser->baud_base)
1005 ret = -EINVAL;
1006 if ((void *)sport->port.mapbase != ser->iomem_base)
1007 ret = -EINVAL;
1008 if (sport->port.iobase != ser->port)
1009 ret = -EINVAL;
1010 if (ser->hub6 != 0)
1011 ret = -EINVAL;
1012 return ret;
1015 static struct uart_ops imx_pops = {
1016 .tx_empty = imx_tx_empty,
1017 .set_mctrl = imx_set_mctrl,
1018 .get_mctrl = imx_get_mctrl,
1019 .stop_tx = imx_stop_tx,
1020 .start_tx = imx_start_tx,
1021 .stop_rx = imx_stop_rx,
1022 .enable_ms = imx_enable_ms,
1023 .break_ctl = imx_break_ctl,
1024 .startup = imx_startup,
1025 .shutdown = imx_shutdown,
1026 .set_termios = imx_set_termios,
1027 .type = imx_type,
1028 .release_port = imx_release_port,
1029 .request_port = imx_request_port,
1030 .config_port = imx_config_port,
1031 .verify_port = imx_verify_port,
1034 static struct imx_port *imx_ports[UART_NR];
1036 #ifdef CONFIG_SERIAL_IMX_CONSOLE
1037 static void imx_console_putchar(struct uart_port *port, int ch)
1039 struct imx_port *sport = (struct imx_port *)port;
1041 while (readl(sport->port.membase + UTS) & UTS_TXFULL)
1042 barrier();
1044 writel(ch, sport->port.membase + URTX0);
1048 * Interrupts are disabled on entering
1050 static void
1051 imx_console_write(struct console *co, const char *s, unsigned int count)
1053 struct imx_port *sport = imx_ports[co->index];
1054 unsigned int old_ucr1, old_ucr2, ucr1;
1057 * First, save UCR1/2 and then disable interrupts
1059 ucr1 = old_ucr1 = readl(sport->port.membase + UCR1);
1060 old_ucr2 = readl(sport->port.membase + UCR2);
1062 if (cpu_is_mx1())
1063 ucr1 |= MX1_UCR1_UARTCLKEN;
1064 ucr1 |= UCR1_UARTEN;
1065 ucr1 &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN);
1067 writel(ucr1, sport->port.membase + UCR1);
1069 writel(old_ucr2 | UCR2_TXEN, sport->port.membase + UCR2);
1071 uart_console_write(&sport->port, s, count, imx_console_putchar);
1074 * Finally, wait for transmitter to become empty
1075 * and restore UCR1/2
1077 while (!(readl(sport->port.membase + USR2) & USR2_TXDC));
1079 writel(old_ucr1, sport->port.membase + UCR1);
1080 writel(old_ucr2, sport->port.membase + UCR2);
1084 * If the port was already initialised (eg, by a boot loader),
1085 * try to determine the current setup.
1087 static void __init
1088 imx_console_get_options(struct imx_port *sport, int *baud,
1089 int *parity, int *bits)
1092 if (readl(sport->port.membase + UCR1) & UCR1_UARTEN) {
1093 /* ok, the port was enabled */
1094 unsigned int ucr2, ubir,ubmr, uartclk;
1095 unsigned int baud_raw;
1096 unsigned int ucfr_rfdiv;
1098 ucr2 = readl(sport->port.membase + UCR2);
1100 *parity = 'n';
1101 if (ucr2 & UCR2_PREN) {
1102 if (ucr2 & UCR2_PROE)
1103 *parity = 'o';
1104 else
1105 *parity = 'e';
1108 if (ucr2 & UCR2_WS)
1109 *bits = 8;
1110 else
1111 *bits = 7;
1113 ubir = readl(sport->port.membase + UBIR) & 0xffff;
1114 ubmr = readl(sport->port.membase + UBMR) & 0xffff;
1116 ucfr_rfdiv = (readl(sport->port.membase + UFCR) & UFCR_RFDIV) >> 7;
1117 if (ucfr_rfdiv == 6)
1118 ucfr_rfdiv = 7;
1119 else
1120 ucfr_rfdiv = 6 - ucfr_rfdiv;
1122 uartclk = clk_get_rate(sport->clk);
1123 uartclk /= ucfr_rfdiv;
1125 { /*
1126 * The next code provides exact computation of
1127 * baud_raw = round(((uartclk/16) * (ubir + 1)) / (ubmr + 1))
1128 * without need of float support or long long division,
1129 * which would be required to prevent 32bit arithmetic overflow
1131 unsigned int mul = ubir + 1;
1132 unsigned int div = 16 * (ubmr + 1);
1133 unsigned int rem = uartclk % div;
1135 baud_raw = (uartclk / div) * mul;
1136 baud_raw += (rem * mul + div / 2) / div;
1137 *baud = (baud_raw + 50) / 100 * 100;
1140 if(*baud != baud_raw)
1141 printk(KERN_INFO "Serial: Console IMX rounded baud rate from %d to %d\n",
1142 baud_raw, *baud);
1146 static int __init
1147 imx_console_setup(struct console *co, char *options)
1149 struct imx_port *sport;
1150 int baud = 9600;
1151 int bits = 8;
1152 int parity = 'n';
1153 int flow = 'n';
1156 * Check whether an invalid uart number has been specified, and
1157 * if so, search for the first available port that does have
1158 * console support.
1160 if (co->index == -1 || co->index >= ARRAY_SIZE(imx_ports))
1161 co->index = 0;
1162 sport = imx_ports[co->index];
1163 if(sport == NULL)
1164 return -ENODEV;
1166 if (options)
1167 uart_parse_options(options, &baud, &parity, &bits, &flow);
1168 else
1169 imx_console_get_options(sport, &baud, &parity, &bits);
1171 imx_setup_ufcr(sport, 0);
1173 return uart_set_options(&sport->port, co, baud, parity, bits, flow);
1176 static struct uart_driver imx_reg;
1177 static struct console imx_console = {
1178 .name = DEV_NAME,
1179 .write = imx_console_write,
1180 .device = uart_console_device,
1181 .setup = imx_console_setup,
1182 .flags = CON_PRINTBUFFER,
1183 .index = -1,
1184 .data = &imx_reg,
1187 #define IMX_CONSOLE &imx_console
1188 #else
1189 #define IMX_CONSOLE NULL
1190 #endif
1192 static struct uart_driver imx_reg = {
1193 .owner = THIS_MODULE,
1194 .driver_name = DRIVER_NAME,
1195 .dev_name = DEV_NAME,
1196 .major = SERIAL_IMX_MAJOR,
1197 .minor = MINOR_START,
1198 .nr = ARRAY_SIZE(imx_ports),
1199 .cons = IMX_CONSOLE,
1202 static int serial_imx_suspend(struct platform_device *dev, pm_message_t state)
1204 struct imx_port *sport = platform_get_drvdata(dev);
1206 if (sport)
1207 uart_suspend_port(&imx_reg, &sport->port);
1209 return 0;
1212 static int serial_imx_resume(struct platform_device *dev)
1214 struct imx_port *sport = platform_get_drvdata(dev);
1216 if (sport)
1217 uart_resume_port(&imx_reg, &sport->port);
1219 return 0;
1222 static int serial_imx_probe(struct platform_device *pdev)
1224 struct imx_port *sport;
1225 struct imxuart_platform_data *pdata;
1226 void __iomem *base;
1227 int ret = 0;
1228 struct resource *res;
1230 sport = kzalloc(sizeof(*sport), GFP_KERNEL);
1231 if (!sport)
1232 return -ENOMEM;
1234 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1235 if (!res) {
1236 ret = -ENODEV;
1237 goto free;
1240 base = ioremap(res->start, PAGE_SIZE);
1241 if (!base) {
1242 ret = -ENOMEM;
1243 goto free;
1246 sport->port.dev = &pdev->dev;
1247 sport->port.mapbase = res->start;
1248 sport->port.membase = base;
1249 sport->port.type = PORT_IMX,
1250 sport->port.iotype = UPIO_MEM;
1251 sport->port.irq = platform_get_irq(pdev, 0);
1252 sport->rxirq = platform_get_irq(pdev, 0);
1253 sport->txirq = platform_get_irq(pdev, 1);
1254 sport->rtsirq = platform_get_irq(pdev, 2);
1255 sport->port.fifosize = 32;
1256 sport->port.ops = &imx_pops;
1257 sport->port.flags = UPF_BOOT_AUTOCONF;
1258 sport->port.line = pdev->id;
1259 init_timer(&sport->timer);
1260 sport->timer.function = imx_timeout;
1261 sport->timer.data = (unsigned long)sport;
1263 sport->clk = clk_get(&pdev->dev, "uart");
1264 if (IS_ERR(sport->clk)) {
1265 ret = PTR_ERR(sport->clk);
1266 goto unmap;
1268 clk_enable(sport->clk);
1270 sport->port.uartclk = clk_get_rate(sport->clk);
1272 imx_ports[pdev->id] = sport;
1274 pdata = pdev->dev.platform_data;
1275 if (pdata && (pdata->flags & IMXUART_HAVE_RTSCTS))
1276 sport->have_rtscts = 1;
1278 #ifdef CONFIG_IRDA
1279 if (pdata && (pdata->flags & IMXUART_IRDA))
1280 sport->use_irda = 1;
1281 #endif
1283 if (pdata && pdata->init) {
1284 ret = pdata->init(pdev);
1285 if (ret)
1286 goto clkput;
1289 ret = uart_add_one_port(&imx_reg, &sport->port);
1290 if (ret)
1291 goto deinit;
1292 platform_set_drvdata(pdev, &sport->port);
1294 return 0;
1295 deinit:
1296 if (pdata && pdata->exit)
1297 pdata->exit(pdev);
1298 clkput:
1299 clk_put(sport->clk);
1300 clk_disable(sport->clk);
1301 unmap:
1302 iounmap(sport->port.membase);
1303 free:
1304 kfree(sport);
1306 return ret;
1309 static int serial_imx_remove(struct platform_device *pdev)
1311 struct imxuart_platform_data *pdata;
1312 struct imx_port *sport = platform_get_drvdata(pdev);
1314 pdata = pdev->dev.platform_data;
1316 platform_set_drvdata(pdev, NULL);
1318 if (sport) {
1319 uart_remove_one_port(&imx_reg, &sport->port);
1320 clk_put(sport->clk);
1323 clk_disable(sport->clk);
1325 if (pdata && pdata->exit)
1326 pdata->exit(pdev);
1328 iounmap(sport->port.membase);
1329 kfree(sport);
1331 return 0;
1334 static struct platform_driver serial_imx_driver = {
1335 .probe = serial_imx_probe,
1336 .remove = serial_imx_remove,
1338 .suspend = serial_imx_suspend,
1339 .resume = serial_imx_resume,
1340 .driver = {
1341 .name = "imx-uart",
1342 .owner = THIS_MODULE,
1346 static int __init imx_serial_init(void)
1348 int ret;
1350 printk(KERN_INFO "Serial: IMX driver\n");
1352 ret = uart_register_driver(&imx_reg);
1353 if (ret)
1354 return ret;
1356 ret = platform_driver_register(&serial_imx_driver);
1357 if (ret != 0)
1358 uart_unregister_driver(&imx_reg);
1360 return 0;
1363 static void __exit imx_serial_exit(void)
1365 platform_driver_unregister(&serial_imx_driver);
1366 uart_unregister_driver(&imx_reg);
1369 module_init(imx_serial_init);
1370 module_exit(imx_serial_exit);
1372 MODULE_AUTHOR("Sascha Hauer");
1373 MODULE_DESCRIPTION("IMX generic serial port driver");
1374 MODULE_LICENSE("GPL");
1375 MODULE_ALIAS("platform:imx-uart");