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1/*
2 * Driver for Motorola IMX serial ports
3 *
4 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
5 *
6 * Author: Sascha Hauer <sascha@saschahauer.de>
7 * Copyright (C) 2004 Pengutronix
8 *
9 * Copyright (C) 2009 emlix GmbH
10 * Author: Fabian Godehardt (added IrDA support for iMX)
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 *
26 * [29-Mar-2005] Mike Lee
27 * Added hardware handshake
28 */
29
30#if defined(CONFIG_SERIAL_IMX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
31#define SUPPORT_SYSRQ
32#endif
33
34#include <linux/module.h>
35#include <linux/ioport.h>
36#include <linux/init.h>
37#include <linux/console.h>
38#include <linux/sysrq.h>
39#include <linux/platform_device.h>
40#include <linux/tty.h>
41#include <linux/tty_flip.h>
42#include <linux/serial_core.h>
43#include <linux/serial.h>
44#include <linux/clk.h>
45#include <linux/delay.h>
46#include <linux/rational.h>
47#include <linux/slab.h>
48#include <linux/of.h>
49#include <linux/of_device.h>
50
51#include <asm/io.h>
52#include <asm/irq.h>
53#include <mach/imx-uart.h>
54
55/* Register definitions */
56#define URXD0 0x0 /* Receiver Register */
57#define URTX0 0x40 /* Transmitter Register */
58#define UCR1 0x80 /* Control Register 1 */
59#define UCR2 0x84 /* Control Register 2 */
60#define UCR3 0x88 /* Control Register 3 */
61#define UCR4 0x8c /* Control Register 4 */
62#define UFCR 0x90 /* FIFO Control Register */
63#define USR1 0x94 /* Status Register 1 */
64#define USR2 0x98 /* Status Register 2 */
65#define UESC 0x9c /* Escape Character Register */
66#define UTIM 0xa0 /* Escape Timer Register */
67#define UBIR 0xa4 /* BRM Incremental Register */
68#define UBMR 0xa8 /* BRM Modulator Register */
69#define UBRC 0xac /* Baud Rate Count Register */
70#define IMX21_ONEMS 0xb0 /* One Millisecond register */
71#define IMX1_UTS 0xd0 /* UART Test Register on i.mx1 */
72#define IMX21_UTS 0xb4 /* UART Test Register on all other i.mx*/
73
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 detect 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 IMX1_UCR1_UARTCLKEN (1<<2) /* UART clock enabled, i.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 IMX21_UCR3_RXDMUXSEL (1<<2) /* RXD Muxed Input Select */
119#define UCR3_INVT (1<<1) /* Inverted Infrared transmission */
120#define UCR3_BPEN (1<<0) /* Preset registers enable */
121#define UCR4_CTSTL_SHF 10 /* CTS trigger level shift */
122#define UCR4_CTSTL_MASK 0x3F /* CTS trigger is 6 bits wide */
123#define UCR4_INVR (1<<9) /* Inverted infrared reception */
124#define UCR4_ENIRI (1<<8) /* Serial infrared interrupt enable */
125#define UCR4_WKEN (1<<7) /* Wake interrupt enable */
126#define UCR4_REF16 (1<<6) /* Ref freq 16 MHz */
127#define UCR4_IRSC (1<<5) /* IR special case */
128#define UCR4_TCEN (1<<3) /* Transmit complete interrupt enable */
129#define UCR4_BKEN (1<<2) /* Break condition interrupt enable */
130#define UCR4_OREN (1<<1) /* Receiver overrun interrupt enable */
131#define UCR4_DREN (1<<0) /* Recv data ready interrupt enable */
132#define UFCR_RXTL_SHF 0 /* Receiver trigger level shift */
133#define UFCR_RFDIV (7<<7) /* Reference freq divider mask */
134#define UFCR_RFDIV_REG(x) (((x) < 7 ? 6 - (x) : 6) << 7)
135#define UFCR_TXTL_SHF 10 /* Transmitter trigger level shift */
136#define USR1_PARITYERR (1<<15) /* Parity error interrupt flag */
137#define USR1_RTSS (1<<14) /* RTS pin status */
138#define USR1_TRDY (1<<13) /* Transmitter ready interrupt/dma flag */
139#define USR1_RTSD (1<<12) /* RTS delta */
140#define USR1_ESCF (1<<11) /* Escape seq interrupt flag */
141#define USR1_FRAMERR (1<<10) /* Frame error interrupt flag */
142#define USR1_RRDY (1<<9) /* Receiver ready interrupt/dma flag */
143#define USR1_TIMEOUT (1<<7) /* Receive timeout interrupt status */
144#define USR1_RXDS (1<<6) /* Receiver idle interrupt flag */
145#define USR1_AIRINT (1<<5) /* Async IR wake interrupt flag */
146#define USR1_AWAKE (1<<4) /* Aysnc wake interrupt flag */
147#define USR2_ADET (1<<15) /* Auto baud rate detect complete */
148#define USR2_TXFE (1<<14) /* Transmit buffer FIFO empty */
149#define USR2_DTRF (1<<13) /* DTR edge interrupt flag */
150#define USR2_IDLE (1<<12) /* Idle condition */
151#define USR2_IRINT (1<<8) /* Serial infrared interrupt flag */
152#define USR2_WAKE (1<<7) /* Wake */
153#define USR2_RTSF (1<<4) /* RTS edge interrupt flag */
154#define USR2_TXDC (1<<3) /* Transmitter complete */
155#define USR2_BRCD (1<<2) /* Break condition */
156#define USR2_ORE (1<<1) /* Overrun error */
157#define USR2_RDR (1<<0) /* Recv data ready */
158#define UTS_FRCPERR (1<<13) /* Force parity error */
159#define UTS_LOOP (1<<12) /* Loop tx and rx */
160#define UTS_TXEMPTY (1<<6) /* TxFIFO empty */
161#define UTS_RXEMPTY (1<<5) /* RxFIFO empty */
162#define UTS_TXFULL (1<<4) /* TxFIFO full */
163#define UTS_RXFULL (1<<3) /* RxFIFO full */
164#define UTS_SOFTRST (1<<0) /* Software reset */
165
166/* We've been assigned a range on the "Low-density serial ports" major */
167#define SERIAL_IMX_MAJOR 207
168#define MINOR_START 16
169#define DEV_NAME "ttymxc"
170#define MAX_INTERNAL_IRQ MXC_INTERNAL_IRQS
171
172/*
173 * This determines how often we check the modem status signals
174 * for any change. They generally aren't connected to an IRQ
175 * so we have to poll them. We also check immediately before
176 * filling the TX fifo incase CTS has been dropped.
177 */
178#define MCTRL_TIMEOUT (250*HZ/1000)
179
180#define DRIVER_NAME "IMX-uart"
181
182#define UART_NR 8
183
184/* i.mx21 type uart runs on all i.mx except i.mx1 */
185enum imx_uart_type {
186 IMX1_UART,
187 IMX21_UART,
188};
189
190/* device type dependent stuff */
191struct imx_uart_data {
192 unsigned uts_reg;
193 enum imx_uart_type devtype;
194};
195
196struct imx_port {
197 struct uart_port port;
198 struct timer_list timer;
199 unsigned int old_status;
200 int txirq,rxirq,rtsirq;
201 unsigned int have_rtscts:1;
202 unsigned int use_irda:1;
203 unsigned int irda_inv_rx:1;
204 unsigned int irda_inv_tx:1;
205 unsigned short trcv_delay; /* transceiver delay */
206 struct clk *clk;
207 struct imx_uart_data *devdata;
208};
209
210#ifdef CONFIG_IRDA
211#define USE_IRDA(sport) ((sport)->use_irda)
212#else
213#define USE_IRDA(sport) (0)
214#endif
215
216static struct imx_uart_data imx_uart_devdata[] = {
217 [IMX1_UART] = {
218 .uts_reg = IMX1_UTS,
219 .devtype = IMX1_UART,
220 },
221 [IMX21_UART] = {
222 .uts_reg = IMX21_UTS,
223 .devtype = IMX21_UART,
224 },
225};
226
227static struct platform_device_id imx_uart_devtype[] = {
228 {
229 .name = "imx1-uart",
230 .driver_data = (kernel_ulong_t) &imx_uart_devdata[IMX1_UART],
231 }, {
232 .name = "imx21-uart",
233 .driver_data = (kernel_ulong_t) &imx_uart_devdata[IMX21_UART],
234 }, {
235 /* sentinel */
236 }
237};
238MODULE_DEVICE_TABLE(platform, imx_uart_devtype);
239
240static struct of_device_id imx_uart_dt_ids[] = {
241 { .compatible = "fsl,imx1-uart", .data = &imx_uart_devdata[IMX1_UART], },
242 { .compatible = "fsl,imx21-uart", .data = &imx_uart_devdata[IMX21_UART], },
243 { /* sentinel */ }
244};
245MODULE_DEVICE_TABLE(of, imx_uart_dt_ids);
246
247static inline unsigned uts_reg(struct imx_port *sport)
248{
249 return sport->devdata->uts_reg;
250}
251
252static inline int is_imx1_uart(struct imx_port *sport)
253{
254 return sport->devdata->devtype == IMX1_UART;
255}
256
257static inline int is_imx21_uart(struct imx_port *sport)
258{
259 return sport->devdata->devtype == IMX21_UART;
260}
261
262/*
263 * Handle any change of modem status signal since we were last called.
264 */
265static void imx_mctrl_check(struct imx_port *sport)
266{
267 unsigned int status, changed;
268
269 status = sport->port.ops->get_mctrl(&sport->port);
270 changed = status ^ sport->old_status;
271
272 if (changed == 0)
273 return;
274
275 sport->old_status = status;
276
277 if (changed & TIOCM_RI)
278 sport->port.icount.rng++;
279 if (changed & TIOCM_DSR)
280 sport->port.icount.dsr++;
281 if (changed & TIOCM_CAR)
282 uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
283 if (changed & TIOCM_CTS)
284 uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
285
286 wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
287}
288
289/*
290 * This is our per-port timeout handler, for checking the
291 * modem status signals.
292 */
293static void imx_timeout(unsigned long data)
294{
295 struct imx_port *sport = (struct imx_port *)data;
296 unsigned long flags;
297
298 if (sport->port.state) {
299 spin_lock_irqsave(&sport->port.lock, flags);
300 imx_mctrl_check(sport);
301 spin_unlock_irqrestore(&sport->port.lock, flags);
302
303 mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
304 }
305}
306
307/*
308 * interrupts disabled on entry
309 */
310static void imx_stop_tx(struct uart_port *port)
311{
312 struct imx_port *sport = (struct imx_port *)port;
313 unsigned long temp;
314
315 if (USE_IRDA(sport)) {
316 /* half duplex - wait for end of transmission */
317 int n = 256;
318 while ((--n > 0) &&
319 !(readl(sport->port.membase + USR2) & USR2_TXDC)) {
320 udelay(5);
321 barrier();
322 }
323 /*
324 * irda transceiver - wait a bit more to avoid
325 * cutoff, hardware dependent
326 */
327 udelay(sport->trcv_delay);
328
329 /*
330 * half duplex - reactivate receive mode,
331 * flush receive pipe echo crap
332 */
333 if (readl(sport->port.membase + USR2) & USR2_TXDC) {
334 temp = readl(sport->port.membase + UCR1);
335 temp &= ~(UCR1_TXMPTYEN | UCR1_TRDYEN);
336 writel(temp, sport->port.membase + UCR1);
337
338 temp = readl(sport->port.membase + UCR4);
339 temp &= ~(UCR4_TCEN);
340 writel(temp, sport->port.membase + UCR4);
341
342 while (readl(sport->port.membase + URXD0) &
343 URXD_CHARRDY)
344 barrier();
345
346 temp = readl(sport->port.membase + UCR1);
347 temp |= UCR1_RRDYEN;
348 writel(temp, sport->port.membase + UCR1);
349
350 temp = readl(sport->port.membase + UCR4);
351 temp |= UCR4_DREN;
352 writel(temp, sport->port.membase + UCR4);
353 }
354 return;
355 }
356
357 temp = readl(sport->port.membase + UCR1);
358 writel(temp & ~UCR1_TXMPTYEN, sport->port.membase + UCR1);
359}
360
361/*
362 * interrupts disabled on entry
363 */
364static void imx_stop_rx(struct uart_port *port)
365{
366 struct imx_port *sport = (struct imx_port *)port;
367 unsigned long temp;
368
369 temp = readl(sport->port.membase + UCR2);
370 writel(temp &~ UCR2_RXEN, sport->port.membase + UCR2);
371}
372
373/*
374 * Set the modem control timer to fire immediately.
375 */
376static void imx_enable_ms(struct uart_port *port)
377{
378 struct imx_port *sport = (struct imx_port *)port;
379
380 mod_timer(&sport->timer, jiffies);
381}
382
383static inline void imx_transmit_buffer(struct imx_port *sport)
384{
385 struct circ_buf *xmit = &sport->port.state->xmit;
386
387 while (!uart_circ_empty(xmit) &&
388 !(readl(sport->port.membase + uts_reg(sport))
389 & UTS_TXFULL)) {
390 /* send xmit->buf[xmit->tail]
391 * out the port here */
392 writel(xmit->buf[xmit->tail], sport->port.membase + URTX0);
393 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
394 sport->port.icount.tx++;
395 }
396
397 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
398 uart_write_wakeup(&sport->port);
399
400 if (uart_circ_empty(xmit))
401 imx_stop_tx(&sport->port);
402}
403
404/*
405 * interrupts disabled on entry
406 */
407static void imx_start_tx(struct uart_port *port)
408{
409 struct imx_port *sport = (struct imx_port *)port;
410 unsigned long temp;
411
412 if (USE_IRDA(sport)) {
413 /* half duplex in IrDA mode; have to disable receive mode */
414 temp = readl(sport->port.membase + UCR4);
415 temp &= ~(UCR4_DREN);
416 writel(temp, sport->port.membase + UCR4);
417
418 temp = readl(sport->port.membase + UCR1);
419 temp &= ~(UCR1_RRDYEN);
420 writel(temp, sport->port.membase + UCR1);
421 }
422
423 temp = readl(sport->port.membase + UCR1);
424 writel(temp | UCR1_TXMPTYEN, sport->port.membase + UCR1);
425
426 if (USE_IRDA(sport)) {
427 temp = readl(sport->port.membase + UCR1);
428 temp |= UCR1_TRDYEN;
429 writel(temp, sport->port.membase + UCR1);
430
431 temp = readl(sport->port.membase + UCR4);
432 temp |= UCR4_TCEN;
433 writel(temp, sport->port.membase + UCR4);
434 }
435
436 if (readl(sport->port.membase + uts_reg(sport)) & UTS_TXEMPTY)
437 imx_transmit_buffer(sport);
438}
439
440static irqreturn_t imx_rtsint(int irq, void *dev_id)
441{
442 struct imx_port *sport = dev_id;
443 unsigned int val;
444 unsigned long flags;
445
446 spin_lock_irqsave(&sport->port.lock, flags);
447
448 writel(USR1_RTSD, sport->port.membase + USR1);
449 val = readl(sport->port.membase + USR1) & USR1_RTSS;
450 uart_handle_cts_change(&sport->port, !!val);
451 wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
452
453 spin_unlock_irqrestore(&sport->port.lock, flags);
454 return IRQ_HANDLED;
455}
456
457static irqreturn_t imx_txint(int irq, void *dev_id)
458{
459 struct imx_port *sport = dev_id;
460 struct circ_buf *xmit = &sport->port.state->xmit;
461 unsigned long flags;
462
463 spin_lock_irqsave(&sport->port.lock,flags);
464 if (sport->port.x_char)
465 {
466 /* Send next char */
467 writel(sport->port.x_char, sport->port.membase + URTX0);
468 goto out;
469 }
470
471 if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
472 imx_stop_tx(&sport->port);
473 goto out;
474 }
475
476 imx_transmit_buffer(sport);
477
478 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
479 uart_write_wakeup(&sport->port);
480
481out:
482 spin_unlock_irqrestore(&sport->port.lock,flags);
483 return IRQ_HANDLED;
484}
485
486static irqreturn_t imx_rxint(int irq, void *dev_id)
487{
488 struct imx_port *sport = dev_id;
489 unsigned int rx,flg,ignored = 0;
490 struct tty_struct *tty = sport->port.state->port.tty;
491 unsigned long flags, temp;
492
493 spin_lock_irqsave(&sport->port.lock,flags);
494
495 while (readl(sport->port.membase + USR2) & USR2_RDR) {
496 flg = TTY_NORMAL;
497 sport->port.icount.rx++;
498
499 rx = readl(sport->port.membase + URXD0);
500
501 temp = readl(sport->port.membase + USR2);
502 if (temp & USR2_BRCD) {
503 writel(USR2_BRCD, sport->port.membase + USR2);
504 if (uart_handle_break(&sport->port))
505 continue;
506 }
507
508 if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx))
509 continue;
510
511 if (rx & (URXD_PRERR | URXD_OVRRUN | URXD_FRMERR) ) {
512 if (rx & URXD_PRERR)
513 sport->port.icount.parity++;
514 else if (rx & URXD_FRMERR)
515 sport->port.icount.frame++;
516 if (rx & URXD_OVRRUN)
517 sport->port.icount.overrun++;
518
519 if (rx & sport->port.ignore_status_mask) {
520 if (++ignored > 100)
521 goto out;
522 continue;
523 }
524
525 rx &= sport->port.read_status_mask;
526
527 if (rx & URXD_PRERR)
528 flg = TTY_PARITY;
529 else if (rx & URXD_FRMERR)
530 flg = TTY_FRAME;
531 if (rx & URXD_OVRRUN)
532 flg = TTY_OVERRUN;
533
534#ifdef SUPPORT_SYSRQ
535 sport->port.sysrq = 0;
536#endif
537 }
538
539 tty_insert_flip_char(tty, rx, flg);
540 }
541
542out:
543 spin_unlock_irqrestore(&sport->port.lock,flags);
544 tty_flip_buffer_push(tty);
545 return IRQ_HANDLED;
546}
547
548static irqreturn_t imx_int(int irq, void *dev_id)
549{
550 struct imx_port *sport = dev_id;
551 unsigned int sts;
552
553 sts = readl(sport->port.membase + USR1);
554
555 if (sts & USR1_RRDY)
556 imx_rxint(irq, dev_id);
557
558 if (sts & USR1_TRDY &&
559 readl(sport->port.membase + UCR1) & UCR1_TXMPTYEN)
560 imx_txint(irq, dev_id);
561
562 if (sts & USR1_RTSD)
563 imx_rtsint(irq, dev_id);
564
565 return IRQ_HANDLED;
566}
567
568/*
569 * Return TIOCSER_TEMT when transmitter is not busy.
570 */
571static unsigned int imx_tx_empty(struct uart_port *port)
572{
573 struct imx_port *sport = (struct imx_port *)port;
574
575 return (readl(sport->port.membase + USR2) & USR2_TXDC) ? TIOCSER_TEMT : 0;
576}
577
578/*
579 * We have a modem side uart, so the meanings of RTS and CTS are inverted.
580 */
581static unsigned int imx_get_mctrl(struct uart_port *port)
582{
583 struct imx_port *sport = (struct imx_port *)port;
584 unsigned int tmp = TIOCM_DSR | TIOCM_CAR;
585
586 if (readl(sport->port.membase + USR1) & USR1_RTSS)
587 tmp |= TIOCM_CTS;
588
589 if (readl(sport->port.membase + UCR2) & UCR2_CTS)
590 tmp |= TIOCM_RTS;
591
592 return tmp;
593}
594
595static void imx_set_mctrl(struct uart_port *port, unsigned int mctrl)
596{
597 struct imx_port *sport = (struct imx_port *)port;
598 unsigned long temp;
599
600 temp = readl(sport->port.membase + UCR2) & ~UCR2_CTS;
601
602 if (mctrl & TIOCM_RTS)
603 temp |= UCR2_CTS;
604
605 writel(temp, sport->port.membase + UCR2);
606}
607
608/*
609 * Interrupts always disabled.
610 */
611static void imx_break_ctl(struct uart_port *port, int break_state)
612{
613 struct imx_port *sport = (struct imx_port *)port;
614 unsigned long flags, temp;
615
616 spin_lock_irqsave(&sport->port.lock, flags);
617
618 temp = readl(sport->port.membase + UCR1) & ~UCR1_SNDBRK;
619
620 if ( break_state != 0 )
621 temp |= UCR1_SNDBRK;
622
623 writel(temp, sport->port.membase + UCR1);
624
625 spin_unlock_irqrestore(&sport->port.lock, flags);
626}
627
628#define TXTL 2 /* reset default */
629#define RXTL 1 /* reset default */
630
631static int imx_setup_ufcr(struct imx_port *sport, unsigned int mode)
632{
633 unsigned int val;
634 unsigned int ufcr_rfdiv;
635
636 /* set receiver / transmitter trigger level.
637 * RFDIV is set such way to satisfy requested uartclk value
638 */
639 val = TXTL << 10 | RXTL;
640 ufcr_rfdiv = (clk_get_rate(sport->clk) + sport->port.uartclk / 2)
641 / sport->port.uartclk;
642
643 if(!ufcr_rfdiv)
644 ufcr_rfdiv = 1;
645
646 val |= UFCR_RFDIV_REG(ufcr_rfdiv);
647
648 writel(val, sport->port.membase + UFCR);
649
650 return 0;
651}
652
653/* half the RX buffer size */
654#define CTSTL 16
655
656static int imx_startup(struct uart_port *port)
657{
658 struct imx_port *sport = (struct imx_port *)port;
659 int retval;
660 unsigned long flags, temp;
661
662 imx_setup_ufcr(sport, 0);
663
664 /* disable the DREN bit (Data Ready interrupt enable) before
665 * requesting IRQs
666 */
667 temp = readl(sport->port.membase + UCR4);
668
669 if (USE_IRDA(sport))
670 temp |= UCR4_IRSC;
671
672 /* set the trigger level for CTS */
673 temp &= ~(UCR4_CTSTL_MASK<< UCR4_CTSTL_SHF);
674 temp |= CTSTL<< UCR4_CTSTL_SHF;
675
676 writel(temp & ~UCR4_DREN, sport->port.membase + UCR4);
677
678 if (USE_IRDA(sport)) {
679 /* reset fifo's and state machines */
680 int i = 100;
681 temp = readl(sport->port.membase + UCR2);
682 temp &= ~UCR2_SRST;
683 writel(temp, sport->port.membase + UCR2);
684 while (!(readl(sport->port.membase + UCR2) & UCR2_SRST) &&
685 (--i > 0)) {
686 udelay(1);
687 }
688 }
689
690 /*
691 * Allocate the IRQ(s) i.MX1 has three interrupts whereas later
692 * chips only have one interrupt.
693 */
694 if (sport->txirq > 0) {
695 retval = request_irq(sport->rxirq, imx_rxint, 0,
696 DRIVER_NAME, sport);
697 if (retval)
698 goto error_out1;
699
700 retval = request_irq(sport->txirq, imx_txint, 0,
701 DRIVER_NAME, sport);
702 if (retval)
703 goto error_out2;
704
705 /* do not use RTS IRQ on IrDA */
706 if (!USE_IRDA(sport)) {
707 retval = request_irq(sport->rtsirq, imx_rtsint,
708 (sport->rtsirq < MAX_INTERNAL_IRQ) ? 0 :
709 IRQF_TRIGGER_FALLING |
710 IRQF_TRIGGER_RISING,
711 DRIVER_NAME, sport);
712 if (retval)
713 goto error_out3;
714 }
715 } else {
716 retval = request_irq(sport->port.irq, imx_int, 0,
717 DRIVER_NAME, sport);
718 if (retval) {
719 free_irq(sport->port.irq, sport);
720 goto error_out1;
721 }
722 }
723
724 /*
725 * Finally, clear and enable interrupts
726 */
727 writel(USR1_RTSD, sport->port.membase + USR1);
728
729 temp = readl(sport->port.membase + UCR1);
730 temp |= UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN;
731
732 if (USE_IRDA(sport)) {
733 temp |= UCR1_IREN;
734 temp &= ~(UCR1_RTSDEN);
735 }
736
737 writel(temp, sport->port.membase + UCR1);
738
739 temp = readl(sport->port.membase + UCR2);
740 temp |= (UCR2_RXEN | UCR2_TXEN);
741 writel(temp, sport->port.membase + UCR2);
742
743 if (USE_IRDA(sport)) {
744 /* clear RX-FIFO */
745 int i = 64;
746 while ((--i > 0) &&
747 (readl(sport->port.membase + URXD0) & URXD_CHARRDY)) {
748 barrier();
749 }
750 }
751
752 if (is_imx21_uart(sport)) {
753 temp = readl(sport->port.membase + UCR3);
754 temp |= IMX21_UCR3_RXDMUXSEL;
755 writel(temp, sport->port.membase + UCR3);
756 }
757
758 if (USE_IRDA(sport)) {
759 temp = readl(sport->port.membase + UCR4);
760 if (sport->irda_inv_rx)
761 temp |= UCR4_INVR;
762 else
763 temp &= ~(UCR4_INVR);
764 writel(temp | UCR4_DREN, sport->port.membase + UCR4);
765
766 temp = readl(sport->port.membase + UCR3);
767 if (sport->irda_inv_tx)
768 temp |= UCR3_INVT;
769 else
770 temp &= ~(UCR3_INVT);
771 writel(temp, sport->port.membase + UCR3);
772 }
773
774 /*
775 * Enable modem status interrupts
776 */
777 spin_lock_irqsave(&sport->port.lock,flags);
778 imx_enable_ms(&sport->port);
779 spin_unlock_irqrestore(&sport->port.lock,flags);
780
781 if (USE_IRDA(sport)) {
782 struct imxuart_platform_data *pdata;
783 pdata = sport->port.dev->platform_data;
784 sport->irda_inv_rx = pdata->irda_inv_rx;
785 sport->irda_inv_tx = pdata->irda_inv_tx;
786 sport->trcv_delay = pdata->transceiver_delay;
787 if (pdata->irda_enable)
788 pdata->irda_enable(1);
789 }
790
791 return 0;
792
793error_out3:
794 if (sport->txirq)
795 free_irq(sport->txirq, sport);
796error_out2:
797 if (sport->rxirq)
798 free_irq(sport->rxirq, sport);
799error_out1:
800 return retval;
801}
802
803static void imx_shutdown(struct uart_port *port)
804{
805 struct imx_port *sport = (struct imx_port *)port;
806 unsigned long temp;
807
808 temp = readl(sport->port.membase + UCR2);
809 temp &= ~(UCR2_TXEN);
810 writel(temp, sport->port.membase + UCR2);
811
812 if (USE_IRDA(sport)) {
813 struct imxuart_platform_data *pdata;
814 pdata = sport->port.dev->platform_data;
815 if (pdata->irda_enable)
816 pdata->irda_enable(0);
817 }
818
819 /*
820 * Stop our timer.
821 */
822 del_timer_sync(&sport->timer);
823
824 /*
825 * Free the interrupts
826 */
827 if (sport->txirq > 0) {
828 if (!USE_IRDA(sport))
829 free_irq(sport->rtsirq, sport);
830 free_irq(sport->txirq, sport);
831 free_irq(sport->rxirq, sport);
832 } else
833 free_irq(sport->port.irq, sport);
834
835 /*
836 * Disable all interrupts, port and break condition.
837 */
838
839 temp = readl(sport->port.membase + UCR1);
840 temp &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN);
841 if (USE_IRDA(sport))
842 temp &= ~(UCR1_IREN);
843
844 writel(temp, sport->port.membase + UCR1);
845}
846
847static void
848imx_set_termios(struct uart_port *port, struct ktermios *termios,
849 struct ktermios *old)
850{
851 struct imx_port *sport = (struct imx_port *)port;
852 unsigned long flags;
853 unsigned int ucr2, old_ucr1, old_txrxen, baud, quot;
854 unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
855 unsigned int div, ufcr;
856 unsigned long num, denom;
857 uint64_t tdiv64;
858
859 /*
860 * If we don't support modem control lines, don't allow
861 * these to be set.
862 */
863 if (0) {
864 termios->c_cflag &= ~(HUPCL | CRTSCTS | CMSPAR);
865 termios->c_cflag |= CLOCAL;
866 }
867
868 /*
869 * We only support CS7 and CS8.
870 */
871 while ((termios->c_cflag & CSIZE) != CS7 &&
872 (termios->c_cflag & CSIZE) != CS8) {
873 termios->c_cflag &= ~CSIZE;
874 termios->c_cflag |= old_csize;
875 old_csize = CS8;
876 }
877
878 if ((termios->c_cflag & CSIZE) == CS8)
879 ucr2 = UCR2_WS | UCR2_SRST | UCR2_IRTS;
880 else
881 ucr2 = UCR2_SRST | UCR2_IRTS;
882
883 if (termios->c_cflag & CRTSCTS) {
884 if( sport->have_rtscts ) {
885 ucr2 &= ~UCR2_IRTS;
886 ucr2 |= UCR2_CTSC;
887 } else {
888 termios->c_cflag &= ~CRTSCTS;
889 }
890 }
891
892 if (termios->c_cflag & CSTOPB)
893 ucr2 |= UCR2_STPB;
894 if (termios->c_cflag & PARENB) {
895 ucr2 |= UCR2_PREN;
896 if (termios->c_cflag & PARODD)
897 ucr2 |= UCR2_PROE;
898 }
899
900 /*
901 * Ask the core to calculate the divisor for us.
902 */
903 baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
904 quot = uart_get_divisor(port, baud);
905
906 spin_lock_irqsave(&sport->port.lock, flags);
907
908 sport->port.read_status_mask = 0;
909 if (termios->c_iflag & INPCK)
910 sport->port.read_status_mask |= (URXD_FRMERR | URXD_PRERR);
911 if (termios->c_iflag & (BRKINT | PARMRK))
912 sport->port.read_status_mask |= URXD_BRK;
913
914 /*
915 * Characters to ignore
916 */
917 sport->port.ignore_status_mask = 0;
918 if (termios->c_iflag & IGNPAR)
919 sport->port.ignore_status_mask |= URXD_PRERR;
920 if (termios->c_iflag & IGNBRK) {
921 sport->port.ignore_status_mask |= URXD_BRK;
922 /*
923 * If we're ignoring parity and break indicators,
924 * ignore overruns too (for real raw support).
925 */
926 if (termios->c_iflag & IGNPAR)
927 sport->port.ignore_status_mask |= URXD_OVRRUN;
928 }
929
930 del_timer_sync(&sport->timer);
931
932 /*
933 * Update the per-port timeout.
934 */
935 uart_update_timeout(port, termios->c_cflag, baud);
936
937 /*
938 * disable interrupts and drain transmitter
939 */
940 old_ucr1 = readl(sport->port.membase + UCR1);
941 writel(old_ucr1 & ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN),
942 sport->port.membase + UCR1);
943
944 while ( !(readl(sport->port.membase + USR2) & USR2_TXDC))
945 barrier();
946
947 /* then, disable everything */
948 old_txrxen = readl(sport->port.membase + UCR2);
949 writel(old_txrxen & ~( UCR2_TXEN | UCR2_RXEN),
950 sport->port.membase + UCR2);
951 old_txrxen &= (UCR2_TXEN | UCR2_RXEN);
952
953 if (USE_IRDA(sport)) {
954 /*
955 * use maximum available submodule frequency to
956 * avoid missing short pulses due to low sampling rate
957 */
958 div = 1;
959 } else {
960 div = sport->port.uartclk / (baud * 16);
961 if (div > 7)
962 div = 7;
963 if (!div)
964 div = 1;
965 }
966
967 rational_best_approximation(16 * div * baud, sport->port.uartclk,
968 1 << 16, 1 << 16, &num, &denom);
969
970 tdiv64 = sport->port.uartclk;
971 tdiv64 *= num;
972 do_div(tdiv64, denom * 16 * div);
973 tty_termios_encode_baud_rate(termios,
974 (speed_t)tdiv64, (speed_t)tdiv64);
975
976 num -= 1;
977 denom -= 1;
978
979 ufcr = readl(sport->port.membase + UFCR);
980 ufcr = (ufcr & (~UFCR_RFDIV)) | UFCR_RFDIV_REG(div);
981 writel(ufcr, sport->port.membase + UFCR);
982
983 writel(num, sport->port.membase + UBIR);
984 writel(denom, sport->port.membase + UBMR);
985
986 if (is_imx21_uart(sport))
987 writel(sport->port.uartclk / div / 1000,
988 sport->port.membase + IMX21_ONEMS);
989
990 writel(old_ucr1, sport->port.membase + UCR1);
991
992 /* set the parity, stop bits and data size */
993 writel(ucr2 | old_txrxen, sport->port.membase + UCR2);
994
995 if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
996 imx_enable_ms(&sport->port);
997
998 spin_unlock_irqrestore(&sport->port.lock, flags);
999}
1000
1001static const char *imx_type(struct uart_port *port)
1002{
1003 struct imx_port *sport = (struct imx_port *)port;
1004
1005 return sport->port.type == PORT_IMX ? "IMX" : NULL;
1006}
1007
1008/*
1009 * Release the memory region(s) being used by 'port'.
1010 */
1011static void imx_release_port(struct uart_port *port)
1012{
1013 struct platform_device *pdev = to_platform_device(port->dev);
1014 struct resource *mmres;
1015
1016 mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1017 release_mem_region(mmres->start, resource_size(mmres));
1018}
1019
1020/*
1021 * Request the memory region(s) being used by 'port'.
1022 */
1023static int imx_request_port(struct uart_port *port)
1024{
1025 struct platform_device *pdev = to_platform_device(port->dev);
1026 struct resource *mmres;
1027 void *ret;
1028
1029 mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1030 if (!mmres)
1031 return -ENODEV;
1032
1033 ret = request_mem_region(mmres->start, resource_size(mmres), "imx-uart");
1034
1035 return ret ? 0 : -EBUSY;
1036}
1037
1038/*
1039 * Configure/autoconfigure the port.
1040 */
1041static void imx_config_port(struct uart_port *port, int flags)
1042{
1043 struct imx_port *sport = (struct imx_port *)port;
1044
1045 if (flags & UART_CONFIG_TYPE &&
1046 imx_request_port(&sport->port) == 0)
1047 sport->port.type = PORT_IMX;
1048}
1049
1050/*
1051 * Verify the new serial_struct (for TIOCSSERIAL).
1052 * The only change we allow are to the flags and type, and
1053 * even then only between PORT_IMX and PORT_UNKNOWN
1054 */
1055static int
1056imx_verify_port(struct uart_port *port, struct serial_struct *ser)
1057{
1058 struct imx_port *sport = (struct imx_port *)port;
1059 int ret = 0;
1060
1061 if (ser->type != PORT_UNKNOWN && ser->type != PORT_IMX)
1062 ret = -EINVAL;
1063 if (sport->port.irq != ser->irq)
1064 ret = -EINVAL;
1065 if (ser->io_type != UPIO_MEM)
1066 ret = -EINVAL;
1067 if (sport->port.uartclk / 16 != ser->baud_base)
1068 ret = -EINVAL;
1069 if ((void *)sport->port.mapbase != ser->iomem_base)
1070 ret = -EINVAL;
1071 if (sport->port.iobase != ser->port)
1072 ret = -EINVAL;
1073 if (ser->hub6 != 0)
1074 ret = -EINVAL;
1075 return ret;
1076}
1077
1078static struct uart_ops imx_pops = {
1079 .tx_empty = imx_tx_empty,
1080 .set_mctrl = imx_set_mctrl,
1081 .get_mctrl = imx_get_mctrl,
1082 .stop_tx = imx_stop_tx,
1083 .start_tx = imx_start_tx,
1084 .stop_rx = imx_stop_rx,
1085 .enable_ms = imx_enable_ms,
1086 .break_ctl = imx_break_ctl,
1087 .startup = imx_startup,
1088 .shutdown = imx_shutdown,
1089 .set_termios = imx_set_termios,
1090 .type = imx_type,
1091 .release_port = imx_release_port,
1092 .request_port = imx_request_port,
1093 .config_port = imx_config_port,
1094 .verify_port = imx_verify_port,
1095};
1096
1097static struct imx_port *imx_ports[UART_NR];
1098
1099#ifdef CONFIG_SERIAL_IMX_CONSOLE
1100static void imx_console_putchar(struct uart_port *port, int ch)
1101{
1102 struct imx_port *sport = (struct imx_port *)port;
1103
1104 while (readl(sport->port.membase + uts_reg(sport)) & UTS_TXFULL)
1105 barrier();
1106
1107 writel(ch, sport->port.membase + URTX0);
1108}
1109
1110/*
1111 * Interrupts are disabled on entering
1112 */
1113static void
1114imx_console_write(struct console *co, const char *s, unsigned int count)
1115{
1116 struct imx_port *sport = imx_ports[co->index];
1117 unsigned int old_ucr1, old_ucr2, ucr1;
1118
1119 /*
1120 * First, save UCR1/2 and then disable interrupts
1121 */
1122 ucr1 = old_ucr1 = readl(sport->port.membase + UCR1);
1123 old_ucr2 = readl(sport->port.membase + UCR2);
1124
1125 if (is_imx1_uart(sport))
1126 ucr1 |= IMX1_UCR1_UARTCLKEN;
1127 ucr1 |= UCR1_UARTEN;
1128 ucr1 &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN);
1129
1130 writel(ucr1, sport->port.membase + UCR1);
1131
1132 writel(old_ucr2 | UCR2_TXEN, sport->port.membase + UCR2);
1133
1134 uart_console_write(&sport->port, s, count, imx_console_putchar);
1135
1136 /*
1137 * Finally, wait for transmitter to become empty
1138 * and restore UCR1/2
1139 */
1140 while (!(readl(sport->port.membase + USR2) & USR2_TXDC));
1141
1142 writel(old_ucr1, sport->port.membase + UCR1);
1143 writel(old_ucr2, sport->port.membase + UCR2);
1144}
1145
1146/*
1147 * If the port was already initialised (eg, by a boot loader),
1148 * try to determine the current setup.
1149 */
1150static void __init
1151imx_console_get_options(struct imx_port *sport, int *baud,
1152 int *parity, int *bits)
1153{
1154
1155 if (readl(sport->port.membase + UCR1) & UCR1_UARTEN) {
1156 /* ok, the port was enabled */
1157 unsigned int ucr2, ubir,ubmr, uartclk;
1158 unsigned int baud_raw;
1159 unsigned int ucfr_rfdiv;
1160
1161 ucr2 = readl(sport->port.membase + UCR2);
1162
1163 *parity = 'n';
1164 if (ucr2 & UCR2_PREN) {
1165 if (ucr2 & UCR2_PROE)
1166 *parity = 'o';
1167 else
1168 *parity = 'e';
1169 }
1170
1171 if (ucr2 & UCR2_WS)
1172 *bits = 8;
1173 else
1174 *bits = 7;
1175
1176 ubir = readl(sport->port.membase + UBIR) & 0xffff;
1177 ubmr = readl(sport->port.membase + UBMR) & 0xffff;
1178
1179 ucfr_rfdiv = (readl(sport->port.membase + UFCR) & UFCR_RFDIV) >> 7;
1180 if (ucfr_rfdiv == 6)
1181 ucfr_rfdiv = 7;
1182 else
1183 ucfr_rfdiv = 6 - ucfr_rfdiv;
1184
1185 uartclk = clk_get_rate(sport->clk);
1186 uartclk /= ucfr_rfdiv;
1187
1188 { /*
1189 * The next code provides exact computation of
1190 * baud_raw = round(((uartclk/16) * (ubir + 1)) / (ubmr + 1))
1191 * without need of float support or long long division,
1192 * which would be required to prevent 32bit arithmetic overflow
1193 */
1194 unsigned int mul = ubir + 1;
1195 unsigned int div = 16 * (ubmr + 1);
1196 unsigned int rem = uartclk % div;
1197
1198 baud_raw = (uartclk / div) * mul;
1199 baud_raw += (rem * mul + div / 2) / div;
1200 *baud = (baud_raw + 50) / 100 * 100;
1201 }
1202
1203 if(*baud != baud_raw)
1204 printk(KERN_INFO "Serial: Console IMX rounded baud rate from %d to %d\n",
1205 baud_raw, *baud);
1206 }
1207}
1208
1209static int __init
1210imx_console_setup(struct console *co, char *options)
1211{
1212 struct imx_port *sport;
1213 int baud = 9600;
1214 int bits = 8;
1215 int parity = 'n';
1216 int flow = 'n';
1217
1218 /*
1219 * Check whether an invalid uart number has been specified, and
1220 * if so, search for the first available port that does have
1221 * console support.
1222 */
1223 if (co->index == -1 || co->index >= ARRAY_SIZE(imx_ports))
1224 co->index = 0;
1225 sport = imx_ports[co->index];
1226 if(sport == NULL)
1227 return -ENODEV;
1228
1229 if (options)
1230 uart_parse_options(options, &baud, &parity, &bits, &flow);
1231 else
1232 imx_console_get_options(sport, &baud, &parity, &bits);
1233
1234 imx_setup_ufcr(sport, 0);
1235
1236 return uart_set_options(&sport->port, co, baud, parity, bits, flow);
1237}
1238
1239static struct uart_driver imx_reg;
1240static struct console imx_console = {
1241 .name = DEV_NAME,
1242 .write = imx_console_write,
1243 .device = uart_console_device,
1244 .setup = imx_console_setup,
1245 .flags = CON_PRINTBUFFER,
1246 .index = -1,
1247 .data = &imx_reg,
1248};
1249
1250#define IMX_CONSOLE &imx_console
1251#else
1252#define IMX_CONSOLE NULL
1253#endif
1254
1255static struct uart_driver imx_reg = {
1256 .owner = THIS_MODULE,
1257 .driver_name = DRIVER_NAME,
1258 .dev_name = DEV_NAME,
1259 .major = SERIAL_IMX_MAJOR,
1260 .minor = MINOR_START,
1261 .nr = ARRAY_SIZE(imx_ports),
1262 .cons = IMX_CONSOLE,
1263};
1264
1265static int serial_imx_suspend(struct platform_device *dev, pm_message_t state)
1266{
1267 struct imx_port *sport = platform_get_drvdata(dev);
1268
1269 if (sport)
1270 uart_suspend_port(&imx_reg, &sport->port);
1271
1272 return 0;
1273}
1274
1275static int serial_imx_resume(struct platform_device *dev)
1276{
1277 struct imx_port *sport = platform_get_drvdata(dev);
1278
1279 if (sport)
1280 uart_resume_port(&imx_reg, &sport->port);
1281
1282 return 0;
1283}
1284
1285#ifdef CONFIG_OF
1286static int serial_imx_probe_dt(struct imx_port *sport,
1287 struct platform_device *pdev)
1288{
1289 static int portnum = 0;
1290 struct device_node *np = pdev->dev.of_node;
1291 const struct of_device_id *of_id =
1292 of_match_device(imx_uart_dt_ids, &pdev->dev);
1293
1294 if (!np)
1295 return -ENODEV;
1296
1297 sport->port.line = portnum++;
1298 if (sport->port.line >= UART_NR)
1299 return -EINVAL;
1300
1301 if (of_get_property(np, "fsl,uart-has-rtscts", NULL))
1302 sport->have_rtscts = 1;
1303
1304 if (of_get_property(np, "fsl,irda-mode", NULL))
1305 sport->use_irda = 1;
1306
1307 sport->devdata = of_id->data;
1308
1309 return 0;
1310}
1311#else
1312static inline int serial_imx_probe_dt(struct imx_port *sport,
1313 struct platform_device *pdev)
1314{
1315 return -ENODEV;
1316}
1317#endif
1318
1319static void serial_imx_probe_pdata(struct imx_port *sport,
1320 struct platform_device *pdev)
1321{
1322 struct imxuart_platform_data *pdata = pdev->dev.platform_data;
1323
1324 sport->port.line = pdev->id;
1325 sport->devdata = (struct imx_uart_data *) pdev->id_entry->driver_data;
1326
1327 if (!pdata)
1328 return;
1329
1330 if (pdata->flags & IMXUART_HAVE_RTSCTS)
1331 sport->have_rtscts = 1;
1332
1333 if (pdata->flags & IMXUART_IRDA)
1334 sport->use_irda = 1;
1335}
1336
1337static int serial_imx_probe(struct platform_device *pdev)
1338{
1339 struct imx_port *sport;
1340 struct imxuart_platform_data *pdata;
1341 void __iomem *base;
1342 int ret = 0;
1343 struct resource *res;
1344
1345 sport = kzalloc(sizeof(*sport), GFP_KERNEL);
1346 if (!sport)
1347 return -ENOMEM;
1348
1349 ret = serial_imx_probe_dt(sport, pdev);
1350 if (ret == -ENODEV)
1351 serial_imx_probe_pdata(sport, pdev);
1352
1353 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1354 if (!res) {
1355 ret = -ENODEV;
1356 goto free;
1357 }
1358
1359 base = ioremap(res->start, PAGE_SIZE);
1360 if (!base) {
1361 ret = -ENOMEM;
1362 goto free;
1363 }
1364
1365 sport->port.dev = &pdev->dev;
1366 sport->port.mapbase = res->start;
1367 sport->port.membase = base;
1368 sport->port.type = PORT_IMX,
1369 sport->port.iotype = UPIO_MEM;
1370 sport->port.irq = platform_get_irq(pdev, 0);
1371 sport->rxirq = platform_get_irq(pdev, 0);
1372 sport->txirq = platform_get_irq(pdev, 1);
1373 sport->rtsirq = platform_get_irq(pdev, 2);
1374 sport->port.fifosize = 32;
1375 sport->port.ops = &imx_pops;
1376 sport->port.flags = UPF_BOOT_AUTOCONF;
1377 init_timer(&sport->timer);
1378 sport->timer.function = imx_timeout;
1379 sport->timer.data = (unsigned long)sport;
1380
1381 sport->clk = clk_get(&pdev->dev, "uart");
1382 if (IS_ERR(sport->clk)) {
1383 ret = PTR_ERR(sport->clk);
1384 goto unmap;
1385 }
1386 clk_enable(sport->clk);
1387
1388 sport->port.uartclk = clk_get_rate(sport->clk);
1389
1390 imx_ports[sport->port.line] = sport;
1391
1392 pdata = pdev->dev.platform_data;
1393 if (pdata && pdata->init) {
1394 ret = pdata->init(pdev);
1395 if (ret)
1396 goto clkput;
1397 }
1398
1399 ret = uart_add_one_port(&imx_reg, &sport->port);
1400 if (ret)
1401 goto deinit;
1402 platform_set_drvdata(pdev, &sport->port);
1403
1404 return 0;
1405deinit:
1406 if (pdata && pdata->exit)
1407 pdata->exit(pdev);
1408clkput:
1409 clk_put(sport->clk);
1410 clk_disable(sport->clk);
1411unmap:
1412 iounmap(sport->port.membase);
1413free:
1414 kfree(sport);
1415
1416 return ret;
1417}
1418
1419static int serial_imx_remove(struct platform_device *pdev)
1420{
1421 struct imxuart_platform_data *pdata;
1422 struct imx_port *sport = platform_get_drvdata(pdev);
1423
1424 pdata = pdev->dev.platform_data;
1425
1426 platform_set_drvdata(pdev, NULL);
1427
1428 if (sport) {
1429 uart_remove_one_port(&imx_reg, &sport->port);
1430 clk_put(sport->clk);
1431 }
1432
1433 clk_disable(sport->clk);
1434
1435 if (pdata && pdata->exit)
1436 pdata->exit(pdev);
1437
1438 iounmap(sport->port.membase);
1439 kfree(sport);
1440
1441 return 0;
1442}
1443
1444static struct platform_driver serial_imx_driver = {
1445 .probe = serial_imx_probe,
1446 .remove = serial_imx_remove,
1447
1448 .suspend = serial_imx_suspend,
1449 .resume = serial_imx_resume,
1450 .id_table = imx_uart_devtype,
1451 .driver = {
1452 .name = "imx-uart",
1453 .owner = THIS_MODULE,
1454 .of_match_table = imx_uart_dt_ids,
1455 },
1456};
1457
1458static int __init imx_serial_init(void)
1459{
1460 int ret;
1461
1462 printk(KERN_INFO "Serial: IMX driver\n");
1463
1464 ret = uart_register_driver(&imx_reg);
1465 if (ret)
1466 return ret;
1467
1468 ret = platform_driver_register(&serial_imx_driver);
1469 if (ret != 0)
1470 uart_unregister_driver(&imx_reg);
1471
1472 return 0;
1473}
1474
1475static void __exit imx_serial_exit(void)
1476{
1477 platform_driver_unregister(&serial_imx_driver);
1478 uart_unregister_driver(&imx_reg);
1479}
1480
1481module_init(imx_serial_init);
1482module_exit(imx_serial_exit);
1483
1484MODULE_AUTHOR("Sascha Hauer");
1485MODULE_DESCRIPTION("IMX generic serial port driver");
1486MODULE_LICENSE("GPL");
1487MODULE_ALIAS("platform:imx-uart");
1/*
2 * Driver for Motorola/Freescale IMX serial ports
3 *
4 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
5 *
6 * Author: Sascha Hauer <sascha@saschahauer.de>
7 * Copyright (C) 2004 Pengutronix
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 */
19
20#if defined(CONFIG_SERIAL_IMX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
21#define SUPPORT_SYSRQ
22#endif
23
24#include <linux/module.h>
25#include <linux/ioport.h>
26#include <linux/init.h>
27#include <linux/console.h>
28#include <linux/sysrq.h>
29#include <linux/platform_device.h>
30#include <linux/tty.h>
31#include <linux/tty_flip.h>
32#include <linux/serial_core.h>
33#include <linux/serial.h>
34#include <linux/clk.h>
35#include <linux/delay.h>
36#include <linux/rational.h>
37#include <linux/slab.h>
38#include <linux/of.h>
39#include <linux/of_device.h>
40#include <linux/io.h>
41#include <linux/dma-mapping.h>
42
43#include <asm/irq.h>
44#include <linux/platform_data/serial-imx.h>
45#include <linux/platform_data/dma-imx.h>
46
47#include "serial_mctrl_gpio.h"
48
49/* Register definitions */
50#define URXD0 0x0 /* Receiver Register */
51#define URTX0 0x40 /* Transmitter Register */
52#define UCR1 0x80 /* Control Register 1 */
53#define UCR2 0x84 /* Control Register 2 */
54#define UCR3 0x88 /* Control Register 3 */
55#define UCR4 0x8c /* Control Register 4 */
56#define UFCR 0x90 /* FIFO Control Register */
57#define USR1 0x94 /* Status Register 1 */
58#define USR2 0x98 /* Status Register 2 */
59#define UESC 0x9c /* Escape Character Register */
60#define UTIM 0xa0 /* Escape Timer Register */
61#define UBIR 0xa4 /* BRM Incremental Register */
62#define UBMR 0xa8 /* BRM Modulator Register */
63#define UBRC 0xac /* Baud Rate Count Register */
64#define IMX21_ONEMS 0xb0 /* One Millisecond register */
65#define IMX1_UTS 0xd0 /* UART Test Register on i.mx1 */
66#define IMX21_UTS 0xb4 /* UART Test Register on all other i.mx*/
67
68/* UART Control Register Bit Fields.*/
69#define URXD_DUMMY_READ (1<<16)
70#define URXD_CHARRDY (1<<15)
71#define URXD_ERR (1<<14)
72#define URXD_OVRRUN (1<<13)
73#define URXD_FRMERR (1<<12)
74#define URXD_BRK (1<<11)
75#define URXD_PRERR (1<<10)
76#define URXD_RX_DATA (0xFF<<0)
77#define UCR1_ADEN (1<<15) /* Auto detect interrupt */
78#define UCR1_ADBR (1<<14) /* Auto detect baud rate */
79#define UCR1_TRDYEN (1<<13) /* Transmitter ready interrupt enable */
80#define UCR1_IDEN (1<<12) /* Idle condition interrupt */
81#define UCR1_ICD_REG(x) (((x) & 3) << 10) /* idle condition detect */
82#define UCR1_RRDYEN (1<<9) /* Recv ready interrupt enable */
83#define UCR1_RDMAEN (1<<8) /* Recv ready DMA enable */
84#define UCR1_IREN (1<<7) /* Infrared interface enable */
85#define UCR1_TXMPTYEN (1<<6) /* Transimitter empty interrupt enable */
86#define UCR1_RTSDEN (1<<5) /* RTS delta interrupt enable */
87#define UCR1_SNDBRK (1<<4) /* Send break */
88#define UCR1_TDMAEN (1<<3) /* Transmitter ready DMA enable */
89#define IMX1_UCR1_UARTCLKEN (1<<2) /* UART clock enabled, i.mx1 only */
90#define UCR1_ATDMAEN (1<<2) /* Aging DMA Timer Enable */
91#define UCR1_DOZE (1<<1) /* Doze */
92#define UCR1_UARTEN (1<<0) /* UART enabled */
93#define UCR2_ESCI (1<<15) /* Escape seq interrupt enable */
94#define UCR2_IRTS (1<<14) /* Ignore RTS pin */
95#define UCR2_CTSC (1<<13) /* CTS pin control */
96#define UCR2_CTS (1<<12) /* Clear to send */
97#define UCR2_ESCEN (1<<11) /* Escape enable */
98#define UCR2_PREN (1<<8) /* Parity enable */
99#define UCR2_PROE (1<<7) /* Parity odd/even */
100#define UCR2_STPB (1<<6) /* Stop */
101#define UCR2_WS (1<<5) /* Word size */
102#define UCR2_RTSEN (1<<4) /* Request to send interrupt enable */
103#define UCR2_ATEN (1<<3) /* Aging Timer Enable */
104#define UCR2_TXEN (1<<2) /* Transmitter enabled */
105#define UCR2_RXEN (1<<1) /* Receiver enabled */
106#define UCR2_SRST (1<<0) /* SW reset */
107#define UCR3_DTREN (1<<13) /* DTR interrupt enable */
108#define UCR3_PARERREN (1<<12) /* Parity enable */
109#define UCR3_FRAERREN (1<<11) /* Frame error interrupt enable */
110#define UCR3_DSR (1<<10) /* Data set ready */
111#define UCR3_DCD (1<<9) /* Data carrier detect */
112#define UCR3_RI (1<<8) /* Ring indicator */
113#define UCR3_ADNIMP (1<<7) /* Autobaud Detection Not Improved */
114#define UCR3_RXDSEN (1<<6) /* Receive status interrupt enable */
115#define UCR3_AIRINTEN (1<<5) /* Async IR wake interrupt enable */
116#define UCR3_AWAKEN (1<<4) /* Async wake interrupt enable */
117#define IMX21_UCR3_RXDMUXSEL (1<<2) /* RXD Muxed Input Select */
118#define UCR3_INVT (1<<1) /* Inverted Infrared transmission */
119#define UCR3_BPEN (1<<0) /* Preset registers enable */
120#define UCR4_CTSTL_SHF 10 /* CTS trigger level shift */
121#define UCR4_CTSTL_MASK 0x3F /* CTS trigger is 6 bits wide */
122#define UCR4_INVR (1<<9) /* Inverted infrared reception */
123#define UCR4_ENIRI (1<<8) /* Serial infrared interrupt enable */
124#define UCR4_WKEN (1<<7) /* Wake interrupt enable */
125#define UCR4_REF16 (1<<6) /* Ref freq 16 MHz */
126#define UCR4_IDDMAEN (1<<6) /* DMA IDLE Condition Detected */
127#define UCR4_IRSC (1<<5) /* IR special case */
128#define UCR4_TCEN (1<<3) /* Transmit complete interrupt enable */
129#define UCR4_BKEN (1<<2) /* Break condition interrupt enable */
130#define UCR4_OREN (1<<1) /* Receiver overrun interrupt enable */
131#define UCR4_DREN (1<<0) /* Recv data ready interrupt enable */
132#define UFCR_RXTL_SHF 0 /* Receiver trigger level shift */
133#define UFCR_DCEDTE (1<<6) /* DCE/DTE mode select */
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_AGTIM (1<<8) /* Ageing timer interrupt flag */
145#define USR1_TIMEOUT (1<<7) /* Receive timeout interrupt status */
146#define USR1_RXDS (1<<6) /* Receiver idle interrupt flag */
147#define USR1_AIRINT (1<<5) /* Async IR wake interrupt flag */
148#define USR1_AWAKE (1<<4) /* Aysnc wake interrupt flag */
149#define USR2_ADET (1<<15) /* Auto baud rate detect complete */
150#define USR2_TXFE (1<<14) /* Transmit buffer FIFO empty */
151#define USR2_DTRF (1<<13) /* DTR edge interrupt flag */
152#define USR2_IDLE (1<<12) /* Idle condition */
153#define USR2_RIDELT (1<<10) /* Ring Interrupt Delta */
154#define USR2_RIIN (1<<9) /* Ring Indicator Input */
155#define USR2_IRINT (1<<8) /* Serial infrared interrupt flag */
156#define USR2_WAKE (1<<7) /* Wake */
157#define USR2_DCDIN (1<<5) /* Data Carrier Detect Input */
158#define USR2_RTSF (1<<4) /* RTS edge interrupt flag */
159#define USR2_TXDC (1<<3) /* Transmitter complete */
160#define USR2_BRCD (1<<2) /* Break condition */
161#define USR2_ORE (1<<1) /* Overrun error */
162#define USR2_RDR (1<<0) /* Recv data ready */
163#define UTS_FRCPERR (1<<13) /* Force parity error */
164#define UTS_LOOP (1<<12) /* Loop tx and rx */
165#define UTS_TXEMPTY (1<<6) /* TxFIFO empty */
166#define UTS_RXEMPTY (1<<5) /* RxFIFO empty */
167#define UTS_TXFULL (1<<4) /* TxFIFO full */
168#define UTS_RXFULL (1<<3) /* RxFIFO full */
169#define UTS_SOFTRST (1<<0) /* Software reset */
170
171/* We've been assigned a range on the "Low-density serial ports" major */
172#define SERIAL_IMX_MAJOR 207
173#define MINOR_START 16
174#define DEV_NAME "ttymxc"
175
176/*
177 * This determines how often we check the modem status signals
178 * for any change. They generally aren't connected to an IRQ
179 * so we have to poll them. We also check immediately before
180 * filling the TX fifo incase CTS has been dropped.
181 */
182#define MCTRL_TIMEOUT (250*HZ/1000)
183
184#define DRIVER_NAME "IMX-uart"
185
186#define UART_NR 8
187
188/* i.MX21 type uart runs on all i.mx except i.MX1 and i.MX6q */
189enum imx_uart_type {
190 IMX1_UART,
191 IMX21_UART,
192 IMX6Q_UART,
193};
194
195/* device type dependent stuff */
196struct imx_uart_data {
197 unsigned uts_reg;
198 enum imx_uart_type devtype;
199};
200
201struct imx_port {
202 struct uart_port port;
203 struct timer_list timer;
204 unsigned int old_status;
205 unsigned int have_rtscts:1;
206 unsigned int dte_mode:1;
207 unsigned int irda_inv_rx:1;
208 unsigned int irda_inv_tx:1;
209 unsigned short trcv_delay; /* transceiver delay */
210 struct clk *clk_ipg;
211 struct clk *clk_per;
212 const struct imx_uart_data *devdata;
213
214 struct mctrl_gpios *gpios;
215
216 /* DMA fields */
217 unsigned int dma_is_inited:1;
218 unsigned int dma_is_enabled:1;
219 unsigned int dma_is_rxing:1;
220 unsigned int dma_is_txing:1;
221 struct dma_chan *dma_chan_rx, *dma_chan_tx;
222 struct scatterlist rx_sgl, tx_sgl[2];
223 void *rx_buf;
224 unsigned int tx_bytes;
225 unsigned int dma_tx_nents;
226 wait_queue_head_t dma_wait;
227 unsigned int saved_reg[10];
228 bool context_saved;
229};
230
231struct imx_port_ucrs {
232 unsigned int ucr1;
233 unsigned int ucr2;
234 unsigned int ucr3;
235};
236
237static struct imx_uart_data imx_uart_devdata[] = {
238 [IMX1_UART] = {
239 .uts_reg = IMX1_UTS,
240 .devtype = IMX1_UART,
241 },
242 [IMX21_UART] = {
243 .uts_reg = IMX21_UTS,
244 .devtype = IMX21_UART,
245 },
246 [IMX6Q_UART] = {
247 .uts_reg = IMX21_UTS,
248 .devtype = IMX6Q_UART,
249 },
250};
251
252static const struct platform_device_id imx_uart_devtype[] = {
253 {
254 .name = "imx1-uart",
255 .driver_data = (kernel_ulong_t) &imx_uart_devdata[IMX1_UART],
256 }, {
257 .name = "imx21-uart",
258 .driver_data = (kernel_ulong_t) &imx_uart_devdata[IMX21_UART],
259 }, {
260 .name = "imx6q-uart",
261 .driver_data = (kernel_ulong_t) &imx_uart_devdata[IMX6Q_UART],
262 }, {
263 /* sentinel */
264 }
265};
266MODULE_DEVICE_TABLE(platform, imx_uart_devtype);
267
268static const struct of_device_id imx_uart_dt_ids[] = {
269 { .compatible = "fsl,imx6q-uart", .data = &imx_uart_devdata[IMX6Q_UART], },
270 { .compatible = "fsl,imx1-uart", .data = &imx_uart_devdata[IMX1_UART], },
271 { .compatible = "fsl,imx21-uart", .data = &imx_uart_devdata[IMX21_UART], },
272 { /* sentinel */ }
273};
274MODULE_DEVICE_TABLE(of, imx_uart_dt_ids);
275
276static inline unsigned uts_reg(struct imx_port *sport)
277{
278 return sport->devdata->uts_reg;
279}
280
281static inline int is_imx1_uart(struct imx_port *sport)
282{
283 return sport->devdata->devtype == IMX1_UART;
284}
285
286static inline int is_imx21_uart(struct imx_port *sport)
287{
288 return sport->devdata->devtype == IMX21_UART;
289}
290
291static inline int is_imx6q_uart(struct imx_port *sport)
292{
293 return sport->devdata->devtype == IMX6Q_UART;
294}
295/*
296 * Save and restore functions for UCR1, UCR2 and UCR3 registers
297 */
298#if defined(CONFIG_SERIAL_IMX_CONSOLE)
299static void imx_port_ucrs_save(struct uart_port *port,
300 struct imx_port_ucrs *ucr)
301{
302 /* save control registers */
303 ucr->ucr1 = readl(port->membase + UCR1);
304 ucr->ucr2 = readl(port->membase + UCR2);
305 ucr->ucr3 = readl(port->membase + UCR3);
306}
307
308static void imx_port_ucrs_restore(struct uart_port *port,
309 struct imx_port_ucrs *ucr)
310{
311 /* restore control registers */
312 writel(ucr->ucr1, port->membase + UCR1);
313 writel(ucr->ucr2, port->membase + UCR2);
314 writel(ucr->ucr3, port->membase + UCR3);
315}
316#endif
317
318static void imx_port_rts_active(struct imx_port *sport, unsigned long *ucr2)
319{
320 *ucr2 &= ~UCR2_CTSC;
321 *ucr2 |= UCR2_CTS;
322
323 mctrl_gpio_set(sport->gpios, sport->port.mctrl | TIOCM_RTS);
324}
325
326static void imx_port_rts_inactive(struct imx_port *sport, unsigned long *ucr2)
327{
328 *ucr2 &= ~(UCR2_CTSC | UCR2_CTS);
329
330 mctrl_gpio_set(sport->gpios, sport->port.mctrl & ~TIOCM_RTS);
331}
332
333static void imx_port_rts_auto(struct imx_port *sport, unsigned long *ucr2)
334{
335 *ucr2 |= UCR2_CTSC;
336}
337
338/*
339 * interrupts disabled on entry
340 */
341static void imx_stop_tx(struct uart_port *port)
342{
343 struct imx_port *sport = (struct imx_port *)port;
344 unsigned long temp;
345
346 /*
347 * We are maybe in the SMP context, so if the DMA TX thread is running
348 * on other cpu, we have to wait for it to finish.
349 */
350 if (sport->dma_is_enabled && sport->dma_is_txing)
351 return;
352
353 temp = readl(port->membase + UCR1);
354 writel(temp & ~UCR1_TXMPTYEN, port->membase + UCR1);
355
356 /* in rs485 mode disable transmitter if shifter is empty */
357 if (port->rs485.flags & SER_RS485_ENABLED &&
358 readl(port->membase + USR2) & USR2_TXDC) {
359 temp = readl(port->membase + UCR2);
360 if (port->rs485.flags & SER_RS485_RTS_AFTER_SEND)
361 imx_port_rts_inactive(sport, &temp);
362 else
363 imx_port_rts_active(sport, &temp);
364 writel(temp, port->membase + UCR2);
365
366 temp = readl(port->membase + UCR4);
367 temp &= ~UCR4_TCEN;
368 writel(temp, port->membase + UCR4);
369 }
370}
371
372/*
373 * interrupts disabled on entry
374 */
375static void imx_stop_rx(struct uart_port *port)
376{
377 struct imx_port *sport = (struct imx_port *)port;
378 unsigned long temp;
379
380 if (sport->dma_is_enabled && sport->dma_is_rxing) {
381 if (sport->port.suspended) {
382 dmaengine_terminate_all(sport->dma_chan_rx);
383 sport->dma_is_rxing = 0;
384 } else {
385 return;
386 }
387 }
388
389 temp = readl(sport->port.membase + UCR2);
390 writel(temp & ~UCR2_RXEN, sport->port.membase + UCR2);
391
392 /* disable the `Receiver Ready Interrrupt` */
393 temp = readl(sport->port.membase + UCR1);
394 writel(temp & ~UCR1_RRDYEN, sport->port.membase + UCR1);
395}
396
397/*
398 * Set the modem control timer to fire immediately.
399 */
400static void imx_enable_ms(struct uart_port *port)
401{
402 struct imx_port *sport = (struct imx_port *)port;
403
404 mod_timer(&sport->timer, jiffies);
405
406 mctrl_gpio_enable_ms(sport->gpios);
407}
408
409static void imx_dma_tx(struct imx_port *sport);
410static inline void imx_transmit_buffer(struct imx_port *sport)
411{
412 struct circ_buf *xmit = &sport->port.state->xmit;
413 unsigned long temp;
414
415 if (sport->port.x_char) {
416 /* Send next char */
417 writel(sport->port.x_char, sport->port.membase + URTX0);
418 sport->port.icount.tx++;
419 sport->port.x_char = 0;
420 return;
421 }
422
423 if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
424 imx_stop_tx(&sport->port);
425 return;
426 }
427
428 if (sport->dma_is_enabled) {
429 /*
430 * We've just sent a X-char Ensure the TX DMA is enabled
431 * and the TX IRQ is disabled.
432 **/
433 temp = readl(sport->port.membase + UCR1);
434 temp &= ~UCR1_TXMPTYEN;
435 if (sport->dma_is_txing) {
436 temp |= UCR1_TDMAEN;
437 writel(temp, sport->port.membase + UCR1);
438 } else {
439 writel(temp, sport->port.membase + UCR1);
440 imx_dma_tx(sport);
441 }
442 }
443
444 while (!uart_circ_empty(xmit) &&
445 !(readl(sport->port.membase + uts_reg(sport)) & UTS_TXFULL)) {
446 /* send xmit->buf[xmit->tail]
447 * out the port here */
448 writel(xmit->buf[xmit->tail], sport->port.membase + URTX0);
449 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
450 sport->port.icount.tx++;
451 }
452
453 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
454 uart_write_wakeup(&sport->port);
455
456 if (uart_circ_empty(xmit))
457 imx_stop_tx(&sport->port);
458}
459
460static void dma_tx_callback(void *data)
461{
462 struct imx_port *sport = data;
463 struct scatterlist *sgl = &sport->tx_sgl[0];
464 struct circ_buf *xmit = &sport->port.state->xmit;
465 unsigned long flags;
466 unsigned long temp;
467
468 spin_lock_irqsave(&sport->port.lock, flags);
469
470 dma_unmap_sg(sport->port.dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
471
472 temp = readl(sport->port.membase + UCR1);
473 temp &= ~UCR1_TDMAEN;
474 writel(temp, sport->port.membase + UCR1);
475
476 /* update the stat */
477 xmit->tail = (xmit->tail + sport->tx_bytes) & (UART_XMIT_SIZE - 1);
478 sport->port.icount.tx += sport->tx_bytes;
479
480 dev_dbg(sport->port.dev, "we finish the TX DMA.\n");
481
482 sport->dma_is_txing = 0;
483
484 spin_unlock_irqrestore(&sport->port.lock, flags);
485
486 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
487 uart_write_wakeup(&sport->port);
488
489 if (waitqueue_active(&sport->dma_wait)) {
490 wake_up(&sport->dma_wait);
491 dev_dbg(sport->port.dev, "exit in %s.\n", __func__);
492 return;
493 }
494
495 spin_lock_irqsave(&sport->port.lock, flags);
496 if (!uart_circ_empty(xmit) && !uart_tx_stopped(&sport->port))
497 imx_dma_tx(sport);
498 spin_unlock_irqrestore(&sport->port.lock, flags);
499}
500
501static void imx_dma_tx(struct imx_port *sport)
502{
503 struct circ_buf *xmit = &sport->port.state->xmit;
504 struct scatterlist *sgl = sport->tx_sgl;
505 struct dma_async_tx_descriptor *desc;
506 struct dma_chan *chan = sport->dma_chan_tx;
507 struct device *dev = sport->port.dev;
508 unsigned long temp;
509 int ret;
510
511 if (sport->dma_is_txing)
512 return;
513
514 sport->tx_bytes = uart_circ_chars_pending(xmit);
515
516 if (xmit->tail < xmit->head) {
517 sport->dma_tx_nents = 1;
518 sg_init_one(sgl, xmit->buf + xmit->tail, sport->tx_bytes);
519 } else {
520 sport->dma_tx_nents = 2;
521 sg_init_table(sgl, 2);
522 sg_set_buf(sgl, xmit->buf + xmit->tail,
523 UART_XMIT_SIZE - xmit->tail);
524 sg_set_buf(sgl + 1, xmit->buf, xmit->head);
525 }
526
527 ret = dma_map_sg(dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
528 if (ret == 0) {
529 dev_err(dev, "DMA mapping error for TX.\n");
530 return;
531 }
532 desc = dmaengine_prep_slave_sg(chan, sgl, sport->dma_tx_nents,
533 DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
534 if (!desc) {
535 dma_unmap_sg(dev, sgl, sport->dma_tx_nents,
536 DMA_TO_DEVICE);
537 dev_err(dev, "We cannot prepare for the TX slave dma!\n");
538 return;
539 }
540 desc->callback = dma_tx_callback;
541 desc->callback_param = sport;
542
543 dev_dbg(dev, "TX: prepare to send %lu bytes by DMA.\n",
544 uart_circ_chars_pending(xmit));
545
546 temp = readl(sport->port.membase + UCR1);
547 temp |= UCR1_TDMAEN;
548 writel(temp, sport->port.membase + UCR1);
549
550 /* fire it */
551 sport->dma_is_txing = 1;
552 dmaengine_submit(desc);
553 dma_async_issue_pending(chan);
554 return;
555}
556
557/*
558 * interrupts disabled on entry
559 */
560static void imx_start_tx(struct uart_port *port)
561{
562 struct imx_port *sport = (struct imx_port *)port;
563 unsigned long temp;
564
565 if (port->rs485.flags & SER_RS485_ENABLED) {
566 temp = readl(port->membase + UCR2);
567 if (port->rs485.flags & SER_RS485_RTS_ON_SEND)
568 imx_port_rts_inactive(sport, &temp);
569 else
570 imx_port_rts_active(sport, &temp);
571 writel(temp, port->membase + UCR2);
572
573 /* enable transmitter and shifter empty irq */
574 temp = readl(port->membase + UCR4);
575 temp |= UCR4_TCEN;
576 writel(temp, port->membase + UCR4);
577 }
578
579 if (!sport->dma_is_enabled) {
580 temp = readl(sport->port.membase + UCR1);
581 writel(temp | UCR1_TXMPTYEN, sport->port.membase + UCR1);
582 }
583
584 if (sport->dma_is_enabled) {
585 if (sport->port.x_char) {
586 /* We have X-char to send, so enable TX IRQ and
587 * disable TX DMA to let TX interrupt to send X-char */
588 temp = readl(sport->port.membase + UCR1);
589 temp &= ~UCR1_TDMAEN;
590 temp |= UCR1_TXMPTYEN;
591 writel(temp, sport->port.membase + UCR1);
592 return;
593 }
594
595 if (!uart_circ_empty(&port->state->xmit) &&
596 !uart_tx_stopped(port))
597 imx_dma_tx(sport);
598 return;
599 }
600}
601
602static irqreturn_t imx_rtsint(int irq, void *dev_id)
603{
604 struct imx_port *sport = dev_id;
605 unsigned int val;
606 unsigned long flags;
607
608 spin_lock_irqsave(&sport->port.lock, flags);
609
610 writel(USR1_RTSD, sport->port.membase + USR1);
611 val = readl(sport->port.membase + USR1) & USR1_RTSS;
612 uart_handle_cts_change(&sport->port, !!val);
613 wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
614
615 spin_unlock_irqrestore(&sport->port.lock, flags);
616 return IRQ_HANDLED;
617}
618
619static irqreturn_t imx_txint(int irq, void *dev_id)
620{
621 struct imx_port *sport = dev_id;
622 unsigned long flags;
623
624 spin_lock_irqsave(&sport->port.lock, flags);
625 imx_transmit_buffer(sport);
626 spin_unlock_irqrestore(&sport->port.lock, flags);
627 return IRQ_HANDLED;
628}
629
630static irqreturn_t imx_rxint(int irq, void *dev_id)
631{
632 struct imx_port *sport = dev_id;
633 unsigned int rx, flg, ignored = 0;
634 struct tty_port *port = &sport->port.state->port;
635 unsigned long flags, temp;
636
637 spin_lock_irqsave(&sport->port.lock, flags);
638
639 while (readl(sport->port.membase + USR2) & USR2_RDR) {
640 flg = TTY_NORMAL;
641 sport->port.icount.rx++;
642
643 rx = readl(sport->port.membase + URXD0);
644
645 temp = readl(sport->port.membase + USR2);
646 if (temp & USR2_BRCD) {
647 writel(USR2_BRCD, sport->port.membase + USR2);
648 if (uart_handle_break(&sport->port))
649 continue;
650 }
651
652 if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx))
653 continue;
654
655 if (unlikely(rx & URXD_ERR)) {
656 if (rx & URXD_BRK)
657 sport->port.icount.brk++;
658 else if (rx & URXD_PRERR)
659 sport->port.icount.parity++;
660 else if (rx & URXD_FRMERR)
661 sport->port.icount.frame++;
662 if (rx & URXD_OVRRUN)
663 sport->port.icount.overrun++;
664
665 if (rx & sport->port.ignore_status_mask) {
666 if (++ignored > 100)
667 goto out;
668 continue;
669 }
670
671 rx &= (sport->port.read_status_mask | 0xFF);
672
673 if (rx & URXD_BRK)
674 flg = TTY_BREAK;
675 else if (rx & URXD_PRERR)
676 flg = TTY_PARITY;
677 else if (rx & URXD_FRMERR)
678 flg = TTY_FRAME;
679 if (rx & URXD_OVRRUN)
680 flg = TTY_OVERRUN;
681
682#ifdef SUPPORT_SYSRQ
683 sport->port.sysrq = 0;
684#endif
685 }
686
687 if (sport->port.ignore_status_mask & URXD_DUMMY_READ)
688 goto out;
689
690 if (tty_insert_flip_char(port, rx, flg) == 0)
691 sport->port.icount.buf_overrun++;
692 }
693
694out:
695 spin_unlock_irqrestore(&sport->port.lock, flags);
696 tty_flip_buffer_push(port);
697 return IRQ_HANDLED;
698}
699
700static int start_rx_dma(struct imx_port *sport);
701/*
702 * If the RXFIFO is filled with some data, and then we
703 * arise a DMA operation to receive them.
704 */
705static void imx_dma_rxint(struct imx_port *sport)
706{
707 unsigned long temp;
708 unsigned long flags;
709
710 spin_lock_irqsave(&sport->port.lock, flags);
711
712 temp = readl(sport->port.membase + USR2);
713 if ((temp & USR2_RDR) && !sport->dma_is_rxing) {
714 sport->dma_is_rxing = 1;
715
716 /* disable the receiver ready and aging timer interrupts */
717 temp = readl(sport->port.membase + UCR1);
718 temp &= ~(UCR1_RRDYEN);
719 writel(temp, sport->port.membase + UCR1);
720
721 temp = readl(sport->port.membase + UCR2);
722 temp &= ~(UCR2_ATEN);
723 writel(temp, sport->port.membase + UCR2);
724
725 /* tell the DMA to receive the data. */
726 start_rx_dma(sport);
727 }
728
729 spin_unlock_irqrestore(&sport->port.lock, flags);
730}
731
732static irqreturn_t imx_int(int irq, void *dev_id)
733{
734 struct imx_port *sport = dev_id;
735 unsigned int sts;
736 unsigned int sts2;
737
738 sts = readl(sport->port.membase + USR1);
739 sts2 = readl(sport->port.membase + USR2);
740
741 if (sts & (USR1_RRDY | USR1_AGTIM)) {
742 if (sport->dma_is_enabled)
743 imx_dma_rxint(sport);
744 else
745 imx_rxint(irq, dev_id);
746 }
747
748 if ((sts & USR1_TRDY &&
749 readl(sport->port.membase + UCR1) & UCR1_TXMPTYEN) ||
750 (sts2 & USR2_TXDC &&
751 readl(sport->port.membase + UCR4) & UCR4_TCEN))
752 imx_txint(irq, dev_id);
753
754 if (sts & USR1_RTSD)
755 imx_rtsint(irq, dev_id);
756
757 if (sts & USR1_AWAKE)
758 writel(USR1_AWAKE, sport->port.membase + USR1);
759
760 if (sts2 & USR2_ORE) {
761 sport->port.icount.overrun++;
762 writel(USR2_ORE, sport->port.membase + USR2);
763 }
764
765 return IRQ_HANDLED;
766}
767
768/*
769 * Return TIOCSER_TEMT when transmitter is not busy.
770 */
771static unsigned int imx_tx_empty(struct uart_port *port)
772{
773 struct imx_port *sport = (struct imx_port *)port;
774 unsigned int ret;
775
776 ret = (readl(sport->port.membase + USR2) & USR2_TXDC) ? TIOCSER_TEMT : 0;
777
778 /* If the TX DMA is working, return 0. */
779 if (sport->dma_is_enabled && sport->dma_is_txing)
780 ret = 0;
781
782 return ret;
783}
784
785/*
786 * We have a modem side uart, so the meanings of RTS and CTS are inverted.
787 */
788static unsigned int imx_get_hwmctrl(struct imx_port *sport)
789{
790 unsigned int tmp = TIOCM_DSR;
791 unsigned usr1 = readl(sport->port.membase + USR1);
792
793 if (usr1 & USR1_RTSS)
794 tmp |= TIOCM_CTS;
795
796 /* in DCE mode DCDIN is always 0 */
797 if (!(usr1 & USR2_DCDIN))
798 tmp |= TIOCM_CAR;
799
800 /* in DCE mode RIIN is always 0 */
801 if (readl(sport->port.membase + USR2) & USR2_RIIN)
802 tmp |= TIOCM_RI;
803
804 return tmp;
805}
806
807static unsigned int imx_get_mctrl(struct uart_port *port)
808{
809 struct imx_port *sport = (struct imx_port *)port;
810 unsigned int ret = imx_get_hwmctrl(sport);
811
812 mctrl_gpio_get(sport->gpios, &ret);
813
814 return ret;
815}
816
817static void imx_set_mctrl(struct uart_port *port, unsigned int mctrl)
818{
819 struct imx_port *sport = (struct imx_port *)port;
820 unsigned long temp;
821
822 if (!(port->rs485.flags & SER_RS485_ENABLED)) {
823 temp = readl(sport->port.membase + UCR2);
824 temp &= ~(UCR2_CTS | UCR2_CTSC);
825 if (mctrl & TIOCM_RTS)
826 temp |= UCR2_CTS | UCR2_CTSC;
827 writel(temp, sport->port.membase + UCR2);
828 }
829
830 temp = readl(sport->port.membase + UCR3) & ~UCR3_DSR;
831 if (!(mctrl & TIOCM_DTR))
832 temp |= UCR3_DSR;
833 writel(temp, sport->port.membase + UCR3);
834
835 temp = readl(sport->port.membase + uts_reg(sport)) & ~UTS_LOOP;
836 if (mctrl & TIOCM_LOOP)
837 temp |= UTS_LOOP;
838 writel(temp, sport->port.membase + uts_reg(sport));
839
840 mctrl_gpio_set(sport->gpios, mctrl);
841}
842
843/*
844 * Interrupts always disabled.
845 */
846static void imx_break_ctl(struct uart_port *port, int break_state)
847{
848 struct imx_port *sport = (struct imx_port *)port;
849 unsigned long flags, temp;
850
851 spin_lock_irqsave(&sport->port.lock, flags);
852
853 temp = readl(sport->port.membase + UCR1) & ~UCR1_SNDBRK;
854
855 if (break_state != 0)
856 temp |= UCR1_SNDBRK;
857
858 writel(temp, sport->port.membase + UCR1);
859
860 spin_unlock_irqrestore(&sport->port.lock, flags);
861}
862
863/*
864 * Handle any change of modem status signal since we were last called.
865 */
866static void imx_mctrl_check(struct imx_port *sport)
867{
868 unsigned int status, changed;
869
870 status = imx_get_hwmctrl(sport);
871 changed = status ^ sport->old_status;
872
873 if (changed == 0)
874 return;
875
876 sport->old_status = status;
877
878 if (changed & TIOCM_RI)
879 sport->port.icount.rng++;
880 if (changed & TIOCM_DSR)
881 sport->port.icount.dsr++;
882 if (changed & TIOCM_CAR)
883 uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
884 if (changed & TIOCM_CTS)
885 uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
886
887 wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
888}
889
890/*
891 * This is our per-port timeout handler, for checking the
892 * modem status signals.
893 */
894static void imx_timeout(unsigned long data)
895{
896 struct imx_port *sport = (struct imx_port *)data;
897 unsigned long flags;
898
899 if (sport->port.state) {
900 spin_lock_irqsave(&sport->port.lock, flags);
901 imx_mctrl_check(sport);
902 spin_unlock_irqrestore(&sport->port.lock, flags);
903
904 mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
905 }
906}
907
908#define RX_BUF_SIZE (PAGE_SIZE)
909static void imx_rx_dma_done(struct imx_port *sport)
910{
911 unsigned long temp;
912 unsigned long flags;
913
914 spin_lock_irqsave(&sport->port.lock, flags);
915
916 /* re-enable interrupts to get notified when new symbols are incoming */
917 temp = readl(sport->port.membase + UCR1);
918 temp |= UCR1_RRDYEN;
919 writel(temp, sport->port.membase + UCR1);
920
921 temp = readl(sport->port.membase + UCR2);
922 temp |= UCR2_ATEN;
923 writel(temp, sport->port.membase + UCR2);
924
925 sport->dma_is_rxing = 0;
926
927 /* Is the shutdown waiting for us? */
928 if (waitqueue_active(&sport->dma_wait))
929 wake_up(&sport->dma_wait);
930
931 spin_unlock_irqrestore(&sport->port.lock, flags);
932}
933
934/*
935 * There are two kinds of RX DMA interrupts(such as in the MX6Q):
936 * [1] the RX DMA buffer is full.
937 * [2] the aging timer expires
938 *
939 * Condition [2] is triggered when a character has been sitting in the FIFO
940 * for at least 8 byte durations.
941 */
942static void dma_rx_callback(void *data)
943{
944 struct imx_port *sport = data;
945 struct dma_chan *chan = sport->dma_chan_rx;
946 struct scatterlist *sgl = &sport->rx_sgl;
947 struct tty_port *port = &sport->port.state->port;
948 struct dma_tx_state state;
949 enum dma_status status;
950 unsigned int count;
951
952 /* unmap it first */
953 dma_unmap_sg(sport->port.dev, sgl, 1, DMA_FROM_DEVICE);
954
955 status = dmaengine_tx_status(chan, (dma_cookie_t)0, &state);
956 count = RX_BUF_SIZE - state.residue;
957
958 dev_dbg(sport->port.dev, "We get %d bytes.\n", count);
959
960 if (count) {
961 if (!(sport->port.ignore_status_mask & URXD_DUMMY_READ)) {
962 int bytes = tty_insert_flip_string(port, sport->rx_buf,
963 count);
964
965 if (bytes != count)
966 sport->port.icount.buf_overrun++;
967 }
968 tty_flip_buffer_push(port);
969 sport->port.icount.rx += count;
970 }
971
972 /*
973 * Restart RX DMA directly if more data is available in order to skip
974 * the roundtrip through the IRQ handler. If there is some data already
975 * in the FIFO, DMA needs to be restarted soon anyways.
976 *
977 * Otherwise stop the DMA and reactivate FIFO IRQs to restart DMA once
978 * data starts to arrive again.
979 */
980 if (readl(sport->port.membase + USR2) & USR2_RDR)
981 start_rx_dma(sport);
982 else
983 imx_rx_dma_done(sport);
984}
985
986static int start_rx_dma(struct imx_port *sport)
987{
988 struct scatterlist *sgl = &sport->rx_sgl;
989 struct dma_chan *chan = sport->dma_chan_rx;
990 struct device *dev = sport->port.dev;
991 struct dma_async_tx_descriptor *desc;
992 int ret;
993
994 sg_init_one(sgl, sport->rx_buf, RX_BUF_SIZE);
995 ret = dma_map_sg(dev, sgl, 1, DMA_FROM_DEVICE);
996 if (ret == 0) {
997 dev_err(dev, "DMA mapping error for RX.\n");
998 return -EINVAL;
999 }
1000 desc = dmaengine_prep_slave_sg(chan, sgl, 1, DMA_DEV_TO_MEM,
1001 DMA_PREP_INTERRUPT);
1002 if (!desc) {
1003 dma_unmap_sg(dev, sgl, 1, DMA_FROM_DEVICE);
1004 dev_err(dev, "We cannot prepare for the RX slave dma!\n");
1005 return -EINVAL;
1006 }
1007 desc->callback = dma_rx_callback;
1008 desc->callback_param = sport;
1009
1010 dev_dbg(dev, "RX: prepare for the DMA.\n");
1011 dmaengine_submit(desc);
1012 dma_async_issue_pending(chan);
1013 return 0;
1014}
1015
1016#define TXTL_DEFAULT 2 /* reset default */
1017#define RXTL_DEFAULT 1 /* reset default */
1018#define TXTL_DMA 8 /* DMA burst setting */
1019#define RXTL_DMA 9 /* DMA burst setting */
1020
1021static void imx_setup_ufcr(struct imx_port *sport,
1022 unsigned char txwl, unsigned char rxwl)
1023{
1024 unsigned int val;
1025
1026 /* set receiver / transmitter trigger level */
1027 val = readl(sport->port.membase + UFCR) & (UFCR_RFDIV | UFCR_DCEDTE);
1028 val |= txwl << UFCR_TXTL_SHF | rxwl;
1029 writel(val, sport->port.membase + UFCR);
1030}
1031
1032static void imx_uart_dma_exit(struct imx_port *sport)
1033{
1034 if (sport->dma_chan_rx) {
1035 dma_release_channel(sport->dma_chan_rx);
1036 sport->dma_chan_rx = NULL;
1037
1038 kfree(sport->rx_buf);
1039 sport->rx_buf = NULL;
1040 }
1041
1042 if (sport->dma_chan_tx) {
1043 dma_release_channel(sport->dma_chan_tx);
1044 sport->dma_chan_tx = NULL;
1045 }
1046
1047 sport->dma_is_inited = 0;
1048}
1049
1050static int imx_uart_dma_init(struct imx_port *sport)
1051{
1052 struct dma_slave_config slave_config = {};
1053 struct device *dev = sport->port.dev;
1054 int ret;
1055
1056 /* Prepare for RX : */
1057 sport->dma_chan_rx = dma_request_slave_channel(dev, "rx");
1058 if (!sport->dma_chan_rx) {
1059 dev_dbg(dev, "cannot get the DMA channel.\n");
1060 ret = -EINVAL;
1061 goto err;
1062 }
1063
1064 slave_config.direction = DMA_DEV_TO_MEM;
1065 slave_config.src_addr = sport->port.mapbase + URXD0;
1066 slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1067 /* one byte less than the watermark level to enable the aging timer */
1068 slave_config.src_maxburst = RXTL_DMA - 1;
1069 ret = dmaengine_slave_config(sport->dma_chan_rx, &slave_config);
1070 if (ret) {
1071 dev_err(dev, "error in RX dma configuration.\n");
1072 goto err;
1073 }
1074
1075 sport->rx_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
1076 if (!sport->rx_buf) {
1077 ret = -ENOMEM;
1078 goto err;
1079 }
1080
1081 /* Prepare for TX : */
1082 sport->dma_chan_tx = dma_request_slave_channel(dev, "tx");
1083 if (!sport->dma_chan_tx) {
1084 dev_err(dev, "cannot get the TX DMA channel!\n");
1085 ret = -EINVAL;
1086 goto err;
1087 }
1088
1089 slave_config.direction = DMA_MEM_TO_DEV;
1090 slave_config.dst_addr = sport->port.mapbase + URTX0;
1091 slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1092 slave_config.dst_maxburst = TXTL_DMA;
1093 ret = dmaengine_slave_config(sport->dma_chan_tx, &slave_config);
1094 if (ret) {
1095 dev_err(dev, "error in TX dma configuration.");
1096 goto err;
1097 }
1098
1099 sport->dma_is_inited = 1;
1100
1101 return 0;
1102err:
1103 imx_uart_dma_exit(sport);
1104 return ret;
1105}
1106
1107static void imx_enable_dma(struct imx_port *sport)
1108{
1109 unsigned long temp;
1110
1111 init_waitqueue_head(&sport->dma_wait);
1112
1113 /* set UCR1 */
1114 temp = readl(sport->port.membase + UCR1);
1115 temp |= UCR1_RDMAEN | UCR1_TDMAEN | UCR1_ATDMAEN;
1116 writel(temp, sport->port.membase + UCR1);
1117
1118 temp = readl(sport->port.membase + UCR2);
1119 temp |= UCR2_ATEN;
1120 writel(temp, sport->port.membase + UCR2);
1121
1122 imx_setup_ufcr(sport, TXTL_DMA, RXTL_DMA);
1123
1124 sport->dma_is_enabled = 1;
1125}
1126
1127static void imx_disable_dma(struct imx_port *sport)
1128{
1129 unsigned long temp;
1130
1131 /* clear UCR1 */
1132 temp = readl(sport->port.membase + UCR1);
1133 temp &= ~(UCR1_RDMAEN | UCR1_TDMAEN | UCR1_ATDMAEN);
1134 writel(temp, sport->port.membase + UCR1);
1135
1136 /* clear UCR2 */
1137 temp = readl(sport->port.membase + UCR2);
1138 temp &= ~(UCR2_CTSC | UCR2_CTS | UCR2_ATEN);
1139 writel(temp, sport->port.membase + UCR2);
1140
1141 imx_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT);
1142
1143 sport->dma_is_enabled = 0;
1144}
1145
1146/* half the RX buffer size */
1147#define CTSTL 16
1148
1149static int imx_startup(struct uart_port *port)
1150{
1151 struct imx_port *sport = (struct imx_port *)port;
1152 int retval, i;
1153 unsigned long flags, temp;
1154
1155 retval = clk_prepare_enable(sport->clk_per);
1156 if (retval)
1157 return retval;
1158 retval = clk_prepare_enable(sport->clk_ipg);
1159 if (retval) {
1160 clk_disable_unprepare(sport->clk_per);
1161 return retval;
1162 }
1163
1164 imx_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT);
1165
1166 /* disable the DREN bit (Data Ready interrupt enable) before
1167 * requesting IRQs
1168 */
1169 temp = readl(sport->port.membase + UCR4);
1170
1171 /* set the trigger level for CTS */
1172 temp &= ~(UCR4_CTSTL_MASK << UCR4_CTSTL_SHF);
1173 temp |= CTSTL << UCR4_CTSTL_SHF;
1174
1175 writel(temp & ~UCR4_DREN, sport->port.membase + UCR4);
1176
1177 /* Can we enable the DMA support? */
1178 if (is_imx6q_uart(sport) && !uart_console(port) &&
1179 !sport->dma_is_inited)
1180 imx_uart_dma_init(sport);
1181
1182 spin_lock_irqsave(&sport->port.lock, flags);
1183 /* Reset fifo's and state machines */
1184 i = 100;
1185
1186 temp = readl(sport->port.membase + UCR2);
1187 temp &= ~UCR2_SRST;
1188 writel(temp, sport->port.membase + UCR2);
1189
1190 while (!(readl(sport->port.membase + UCR2) & UCR2_SRST) && (--i > 0))
1191 udelay(1);
1192
1193 /*
1194 * Finally, clear and enable interrupts
1195 */
1196 writel(USR1_RTSD, sport->port.membase + USR1);
1197 writel(USR2_ORE, sport->port.membase + USR2);
1198
1199 if (sport->dma_is_inited && !sport->dma_is_enabled)
1200 imx_enable_dma(sport);
1201
1202 temp = readl(sport->port.membase + UCR1);
1203 temp |= UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN;
1204
1205 writel(temp, sport->port.membase + UCR1);
1206
1207 temp = readl(sport->port.membase + UCR4);
1208 temp |= UCR4_OREN;
1209 writel(temp, sport->port.membase + UCR4);
1210
1211 temp = readl(sport->port.membase + UCR2);
1212 temp |= (UCR2_RXEN | UCR2_TXEN);
1213 if (!sport->have_rtscts)
1214 temp |= UCR2_IRTS;
1215 writel(temp, sport->port.membase + UCR2);
1216
1217 if (!is_imx1_uart(sport)) {
1218 temp = readl(sport->port.membase + UCR3);
1219 temp |= IMX21_UCR3_RXDMUXSEL | UCR3_ADNIMP;
1220 writel(temp, sport->port.membase + UCR3);
1221 }
1222
1223 /*
1224 * Enable modem status interrupts
1225 */
1226 imx_enable_ms(&sport->port);
1227 spin_unlock_irqrestore(&sport->port.lock, flags);
1228
1229 return 0;
1230}
1231
1232static void imx_shutdown(struct uart_port *port)
1233{
1234 struct imx_port *sport = (struct imx_port *)port;
1235 unsigned long temp;
1236 unsigned long flags;
1237
1238 if (sport->dma_is_enabled) {
1239 int ret;
1240
1241 /* We have to wait for the DMA to finish. */
1242 ret = wait_event_interruptible(sport->dma_wait,
1243 !sport->dma_is_rxing && !sport->dma_is_txing);
1244 if (ret != 0) {
1245 sport->dma_is_rxing = 0;
1246 sport->dma_is_txing = 0;
1247 dmaengine_terminate_all(sport->dma_chan_tx);
1248 dmaengine_terminate_all(sport->dma_chan_rx);
1249 }
1250 spin_lock_irqsave(&sport->port.lock, flags);
1251 imx_stop_tx(port);
1252 imx_stop_rx(port);
1253 imx_disable_dma(sport);
1254 spin_unlock_irqrestore(&sport->port.lock, flags);
1255 imx_uart_dma_exit(sport);
1256 }
1257
1258 mctrl_gpio_disable_ms(sport->gpios);
1259
1260 spin_lock_irqsave(&sport->port.lock, flags);
1261 temp = readl(sport->port.membase + UCR2);
1262 temp &= ~(UCR2_TXEN);
1263 writel(temp, sport->port.membase + UCR2);
1264 spin_unlock_irqrestore(&sport->port.lock, flags);
1265
1266 /*
1267 * Stop our timer.
1268 */
1269 del_timer_sync(&sport->timer);
1270
1271 /*
1272 * Disable all interrupts, port and break condition.
1273 */
1274
1275 spin_lock_irqsave(&sport->port.lock, flags);
1276 temp = readl(sport->port.membase + UCR1);
1277 temp &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN);
1278
1279 writel(temp, sport->port.membase + UCR1);
1280 spin_unlock_irqrestore(&sport->port.lock, flags);
1281
1282 clk_disable_unprepare(sport->clk_per);
1283 clk_disable_unprepare(sport->clk_ipg);
1284}
1285
1286static void imx_flush_buffer(struct uart_port *port)
1287{
1288 struct imx_port *sport = (struct imx_port *)port;
1289 struct scatterlist *sgl = &sport->tx_sgl[0];
1290 unsigned long temp;
1291 int i = 100, ubir, ubmr, uts;
1292
1293 if (!sport->dma_chan_tx)
1294 return;
1295
1296 sport->tx_bytes = 0;
1297 dmaengine_terminate_all(sport->dma_chan_tx);
1298 if (sport->dma_is_txing) {
1299 dma_unmap_sg(sport->port.dev, sgl, sport->dma_tx_nents,
1300 DMA_TO_DEVICE);
1301 temp = readl(sport->port.membase + UCR1);
1302 temp &= ~UCR1_TDMAEN;
1303 writel(temp, sport->port.membase + UCR1);
1304 sport->dma_is_txing = false;
1305 }
1306
1307 /*
1308 * According to the Reference Manual description of the UART SRST bit:
1309 * "Reset the transmit and receive state machines,
1310 * all FIFOs and register USR1, USR2, UBIR, UBMR, UBRC, URXD, UTXD
1311 * and UTS[6-3]". As we don't need to restore the old values from
1312 * USR1, USR2, URXD, UTXD, only save/restore the other four registers
1313 */
1314 ubir = readl(sport->port.membase + UBIR);
1315 ubmr = readl(sport->port.membase + UBMR);
1316 uts = readl(sport->port.membase + IMX21_UTS);
1317
1318 temp = readl(sport->port.membase + UCR2);
1319 temp &= ~UCR2_SRST;
1320 writel(temp, sport->port.membase + UCR2);
1321
1322 while (!(readl(sport->port.membase + UCR2) & UCR2_SRST) && (--i > 0))
1323 udelay(1);
1324
1325 /* Restore the registers */
1326 writel(ubir, sport->port.membase + UBIR);
1327 writel(ubmr, sport->port.membase + UBMR);
1328 writel(uts, sport->port.membase + IMX21_UTS);
1329}
1330
1331static void
1332imx_set_termios(struct uart_port *port, struct ktermios *termios,
1333 struct ktermios *old)
1334{
1335 struct imx_port *sport = (struct imx_port *)port;
1336 unsigned long flags;
1337 unsigned long ucr2, old_ucr1, old_ucr2;
1338 unsigned int baud, quot;
1339 unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
1340 unsigned long div, ufcr;
1341 unsigned long num, denom;
1342 uint64_t tdiv64;
1343
1344 /*
1345 * We only support CS7 and CS8.
1346 */
1347 while ((termios->c_cflag & CSIZE) != CS7 &&
1348 (termios->c_cflag & CSIZE) != CS8) {
1349 termios->c_cflag &= ~CSIZE;
1350 termios->c_cflag |= old_csize;
1351 old_csize = CS8;
1352 }
1353
1354 if ((termios->c_cflag & CSIZE) == CS8)
1355 ucr2 = UCR2_WS | UCR2_SRST | UCR2_IRTS;
1356 else
1357 ucr2 = UCR2_SRST | UCR2_IRTS;
1358
1359 if (termios->c_cflag & CRTSCTS) {
1360 if (sport->have_rtscts) {
1361 ucr2 &= ~UCR2_IRTS;
1362
1363 if (port->rs485.flags & SER_RS485_ENABLED) {
1364 /*
1365 * RTS is mandatory for rs485 operation, so keep
1366 * it under manual control and keep transmitter
1367 * disabled.
1368 */
1369 if (port->rs485.flags &
1370 SER_RS485_RTS_AFTER_SEND)
1371 imx_port_rts_inactive(sport, &ucr2);
1372 else
1373 imx_port_rts_active(sport, &ucr2);
1374 } else {
1375 imx_port_rts_auto(sport, &ucr2);
1376 }
1377 } else {
1378 termios->c_cflag &= ~CRTSCTS;
1379 }
1380 } else if (port->rs485.flags & SER_RS485_ENABLED) {
1381 /* disable transmitter */
1382 if (port->rs485.flags & SER_RS485_RTS_AFTER_SEND)
1383 imx_port_rts_inactive(sport, &ucr2);
1384 else
1385 imx_port_rts_active(sport, &ucr2);
1386 }
1387
1388
1389 if (termios->c_cflag & CSTOPB)
1390 ucr2 |= UCR2_STPB;
1391 if (termios->c_cflag & PARENB) {
1392 ucr2 |= UCR2_PREN;
1393 if (termios->c_cflag & PARODD)
1394 ucr2 |= UCR2_PROE;
1395 }
1396
1397 del_timer_sync(&sport->timer);
1398
1399 /*
1400 * Ask the core to calculate the divisor for us.
1401 */
1402 baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
1403 quot = uart_get_divisor(port, baud);
1404
1405 spin_lock_irqsave(&sport->port.lock, flags);
1406
1407 sport->port.read_status_mask = 0;
1408 if (termios->c_iflag & INPCK)
1409 sport->port.read_status_mask |= (URXD_FRMERR | URXD_PRERR);
1410 if (termios->c_iflag & (BRKINT | PARMRK))
1411 sport->port.read_status_mask |= URXD_BRK;
1412
1413 /*
1414 * Characters to ignore
1415 */
1416 sport->port.ignore_status_mask = 0;
1417 if (termios->c_iflag & IGNPAR)
1418 sport->port.ignore_status_mask |= URXD_PRERR | URXD_FRMERR;
1419 if (termios->c_iflag & IGNBRK) {
1420 sport->port.ignore_status_mask |= URXD_BRK;
1421 /*
1422 * If we're ignoring parity and break indicators,
1423 * ignore overruns too (for real raw support).
1424 */
1425 if (termios->c_iflag & IGNPAR)
1426 sport->port.ignore_status_mask |= URXD_OVRRUN;
1427 }
1428
1429 if ((termios->c_cflag & CREAD) == 0)
1430 sport->port.ignore_status_mask |= URXD_DUMMY_READ;
1431
1432 /*
1433 * Update the per-port timeout.
1434 */
1435 uart_update_timeout(port, termios->c_cflag, baud);
1436
1437 /*
1438 * disable interrupts and drain transmitter
1439 */
1440 old_ucr1 = readl(sport->port.membase + UCR1);
1441 writel(old_ucr1 & ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN),
1442 sport->port.membase + UCR1);
1443
1444 while (!(readl(sport->port.membase + USR2) & USR2_TXDC))
1445 barrier();
1446
1447 /* then, disable everything */
1448 old_ucr2 = readl(sport->port.membase + UCR2);
1449 writel(old_ucr2 & ~(UCR2_TXEN | UCR2_RXEN),
1450 sport->port.membase + UCR2);
1451 old_ucr2 &= (UCR2_TXEN | UCR2_RXEN | UCR2_ATEN);
1452
1453 /* custom-baudrate handling */
1454 div = sport->port.uartclk / (baud * 16);
1455 if (baud == 38400 && quot != div)
1456 baud = sport->port.uartclk / (quot * 16);
1457
1458 div = sport->port.uartclk / (baud * 16);
1459 if (div > 7)
1460 div = 7;
1461 if (!div)
1462 div = 1;
1463
1464 rational_best_approximation(16 * div * baud, sport->port.uartclk,
1465 1 << 16, 1 << 16, &num, &denom);
1466
1467 tdiv64 = sport->port.uartclk;
1468 tdiv64 *= num;
1469 do_div(tdiv64, denom * 16 * div);
1470 tty_termios_encode_baud_rate(termios,
1471 (speed_t)tdiv64, (speed_t)tdiv64);
1472
1473 num -= 1;
1474 denom -= 1;
1475
1476 ufcr = readl(sport->port.membase + UFCR);
1477 ufcr = (ufcr & (~UFCR_RFDIV)) | UFCR_RFDIV_REG(div);
1478 if (sport->dte_mode)
1479 ufcr |= UFCR_DCEDTE;
1480 writel(ufcr, sport->port.membase + UFCR);
1481
1482 writel(num, sport->port.membase + UBIR);
1483 writel(denom, sport->port.membase + UBMR);
1484
1485 if (!is_imx1_uart(sport))
1486 writel(sport->port.uartclk / div / 1000,
1487 sport->port.membase + IMX21_ONEMS);
1488
1489 writel(old_ucr1, sport->port.membase + UCR1);
1490
1491 /* set the parity, stop bits and data size */
1492 writel(ucr2 | old_ucr2, sport->port.membase + UCR2);
1493
1494 if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
1495 imx_enable_ms(&sport->port);
1496
1497 spin_unlock_irqrestore(&sport->port.lock, flags);
1498}
1499
1500static const char *imx_type(struct uart_port *port)
1501{
1502 struct imx_port *sport = (struct imx_port *)port;
1503
1504 return sport->port.type == PORT_IMX ? "IMX" : NULL;
1505}
1506
1507/*
1508 * Configure/autoconfigure the port.
1509 */
1510static void imx_config_port(struct uart_port *port, int flags)
1511{
1512 struct imx_port *sport = (struct imx_port *)port;
1513
1514 if (flags & UART_CONFIG_TYPE)
1515 sport->port.type = PORT_IMX;
1516}
1517
1518/*
1519 * Verify the new serial_struct (for TIOCSSERIAL).
1520 * The only change we allow are to the flags and type, and
1521 * even then only between PORT_IMX and PORT_UNKNOWN
1522 */
1523static int
1524imx_verify_port(struct uart_port *port, struct serial_struct *ser)
1525{
1526 struct imx_port *sport = (struct imx_port *)port;
1527 int ret = 0;
1528
1529 if (ser->type != PORT_UNKNOWN && ser->type != PORT_IMX)
1530 ret = -EINVAL;
1531 if (sport->port.irq != ser->irq)
1532 ret = -EINVAL;
1533 if (ser->io_type != UPIO_MEM)
1534 ret = -EINVAL;
1535 if (sport->port.uartclk / 16 != ser->baud_base)
1536 ret = -EINVAL;
1537 if (sport->port.mapbase != (unsigned long)ser->iomem_base)
1538 ret = -EINVAL;
1539 if (sport->port.iobase != ser->port)
1540 ret = -EINVAL;
1541 if (ser->hub6 != 0)
1542 ret = -EINVAL;
1543 return ret;
1544}
1545
1546#if defined(CONFIG_CONSOLE_POLL)
1547
1548static int imx_poll_init(struct uart_port *port)
1549{
1550 struct imx_port *sport = (struct imx_port *)port;
1551 unsigned long flags;
1552 unsigned long temp;
1553 int retval;
1554
1555 retval = clk_prepare_enable(sport->clk_ipg);
1556 if (retval)
1557 return retval;
1558 retval = clk_prepare_enable(sport->clk_per);
1559 if (retval)
1560 clk_disable_unprepare(sport->clk_ipg);
1561
1562 imx_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT);
1563
1564 spin_lock_irqsave(&sport->port.lock, flags);
1565
1566 temp = readl(sport->port.membase + UCR1);
1567 if (is_imx1_uart(sport))
1568 temp |= IMX1_UCR1_UARTCLKEN;
1569 temp |= UCR1_UARTEN | UCR1_RRDYEN;
1570 temp &= ~(UCR1_TXMPTYEN | UCR1_RTSDEN);
1571 writel(temp, sport->port.membase + UCR1);
1572
1573 temp = readl(sport->port.membase + UCR2);
1574 temp |= UCR2_RXEN;
1575 writel(temp, sport->port.membase + UCR2);
1576
1577 spin_unlock_irqrestore(&sport->port.lock, flags);
1578
1579 return 0;
1580}
1581
1582static int imx_poll_get_char(struct uart_port *port)
1583{
1584 if (!(readl_relaxed(port->membase + USR2) & USR2_RDR))
1585 return NO_POLL_CHAR;
1586
1587 return readl_relaxed(port->membase + URXD0) & URXD_RX_DATA;
1588}
1589
1590static void imx_poll_put_char(struct uart_port *port, unsigned char c)
1591{
1592 unsigned int status;
1593
1594 /* drain */
1595 do {
1596 status = readl_relaxed(port->membase + USR1);
1597 } while (~status & USR1_TRDY);
1598
1599 /* write */
1600 writel_relaxed(c, port->membase + URTX0);
1601
1602 /* flush */
1603 do {
1604 status = readl_relaxed(port->membase + USR2);
1605 } while (~status & USR2_TXDC);
1606}
1607#endif
1608
1609static int imx_rs485_config(struct uart_port *port,
1610 struct serial_rs485 *rs485conf)
1611{
1612 struct imx_port *sport = (struct imx_port *)port;
1613
1614 /* unimplemented */
1615 rs485conf->delay_rts_before_send = 0;
1616 rs485conf->delay_rts_after_send = 0;
1617 rs485conf->flags |= SER_RS485_RX_DURING_TX;
1618
1619 /* RTS is required to control the transmitter */
1620 if (!sport->have_rtscts)
1621 rs485conf->flags &= ~SER_RS485_ENABLED;
1622
1623 if (rs485conf->flags & SER_RS485_ENABLED) {
1624 unsigned long temp;
1625
1626 /* disable transmitter */
1627 temp = readl(sport->port.membase + UCR2);
1628 if (rs485conf->flags & SER_RS485_RTS_AFTER_SEND)
1629 imx_port_rts_inactive(sport, &temp);
1630 else
1631 imx_port_rts_active(sport, &temp);
1632 writel(temp, sport->port.membase + UCR2);
1633 }
1634
1635 port->rs485 = *rs485conf;
1636
1637 return 0;
1638}
1639
1640static struct uart_ops imx_pops = {
1641 .tx_empty = imx_tx_empty,
1642 .set_mctrl = imx_set_mctrl,
1643 .get_mctrl = imx_get_mctrl,
1644 .stop_tx = imx_stop_tx,
1645 .start_tx = imx_start_tx,
1646 .stop_rx = imx_stop_rx,
1647 .enable_ms = imx_enable_ms,
1648 .break_ctl = imx_break_ctl,
1649 .startup = imx_startup,
1650 .shutdown = imx_shutdown,
1651 .flush_buffer = imx_flush_buffer,
1652 .set_termios = imx_set_termios,
1653 .type = imx_type,
1654 .config_port = imx_config_port,
1655 .verify_port = imx_verify_port,
1656#if defined(CONFIG_CONSOLE_POLL)
1657 .poll_init = imx_poll_init,
1658 .poll_get_char = imx_poll_get_char,
1659 .poll_put_char = imx_poll_put_char,
1660#endif
1661};
1662
1663static struct imx_port *imx_ports[UART_NR];
1664
1665#ifdef CONFIG_SERIAL_IMX_CONSOLE
1666static void imx_console_putchar(struct uart_port *port, int ch)
1667{
1668 struct imx_port *sport = (struct imx_port *)port;
1669
1670 while (readl(sport->port.membase + uts_reg(sport)) & UTS_TXFULL)
1671 barrier();
1672
1673 writel(ch, sport->port.membase + URTX0);
1674}
1675
1676/*
1677 * Interrupts are disabled on entering
1678 */
1679static void
1680imx_console_write(struct console *co, const char *s, unsigned int count)
1681{
1682 struct imx_port *sport = imx_ports[co->index];
1683 struct imx_port_ucrs old_ucr;
1684 unsigned int ucr1;
1685 unsigned long flags = 0;
1686 int locked = 1;
1687 int retval;
1688
1689 retval = clk_enable(sport->clk_per);
1690 if (retval)
1691 return;
1692 retval = clk_enable(sport->clk_ipg);
1693 if (retval) {
1694 clk_disable(sport->clk_per);
1695 return;
1696 }
1697
1698 if (sport->port.sysrq)
1699 locked = 0;
1700 else if (oops_in_progress)
1701 locked = spin_trylock_irqsave(&sport->port.lock, flags);
1702 else
1703 spin_lock_irqsave(&sport->port.lock, flags);
1704
1705 /*
1706 * First, save UCR1/2/3 and then disable interrupts
1707 */
1708 imx_port_ucrs_save(&sport->port, &old_ucr);
1709 ucr1 = old_ucr.ucr1;
1710
1711 if (is_imx1_uart(sport))
1712 ucr1 |= IMX1_UCR1_UARTCLKEN;
1713 ucr1 |= UCR1_UARTEN;
1714 ucr1 &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN);
1715
1716 writel(ucr1, sport->port.membase + UCR1);
1717
1718 writel(old_ucr.ucr2 | UCR2_TXEN, sport->port.membase + UCR2);
1719
1720 uart_console_write(&sport->port, s, count, imx_console_putchar);
1721
1722 /*
1723 * Finally, wait for transmitter to become empty
1724 * and restore UCR1/2/3
1725 */
1726 while (!(readl(sport->port.membase + USR2) & USR2_TXDC));
1727
1728 imx_port_ucrs_restore(&sport->port, &old_ucr);
1729
1730 if (locked)
1731 spin_unlock_irqrestore(&sport->port.lock, flags);
1732
1733 clk_disable(sport->clk_ipg);
1734 clk_disable(sport->clk_per);
1735}
1736
1737/*
1738 * If the port was already initialised (eg, by a boot loader),
1739 * try to determine the current setup.
1740 */
1741static void __init
1742imx_console_get_options(struct imx_port *sport, int *baud,
1743 int *parity, int *bits)
1744{
1745
1746 if (readl(sport->port.membase + UCR1) & UCR1_UARTEN) {
1747 /* ok, the port was enabled */
1748 unsigned int ucr2, ubir, ubmr, uartclk;
1749 unsigned int baud_raw;
1750 unsigned int ucfr_rfdiv;
1751
1752 ucr2 = readl(sport->port.membase + UCR2);
1753
1754 *parity = 'n';
1755 if (ucr2 & UCR2_PREN) {
1756 if (ucr2 & UCR2_PROE)
1757 *parity = 'o';
1758 else
1759 *parity = 'e';
1760 }
1761
1762 if (ucr2 & UCR2_WS)
1763 *bits = 8;
1764 else
1765 *bits = 7;
1766
1767 ubir = readl(sport->port.membase + UBIR) & 0xffff;
1768 ubmr = readl(sport->port.membase + UBMR) & 0xffff;
1769
1770 ucfr_rfdiv = (readl(sport->port.membase + UFCR) & UFCR_RFDIV) >> 7;
1771 if (ucfr_rfdiv == 6)
1772 ucfr_rfdiv = 7;
1773 else
1774 ucfr_rfdiv = 6 - ucfr_rfdiv;
1775
1776 uartclk = clk_get_rate(sport->clk_per);
1777 uartclk /= ucfr_rfdiv;
1778
1779 { /*
1780 * The next code provides exact computation of
1781 * baud_raw = round(((uartclk/16) * (ubir + 1)) / (ubmr + 1))
1782 * without need of float support or long long division,
1783 * which would be required to prevent 32bit arithmetic overflow
1784 */
1785 unsigned int mul = ubir + 1;
1786 unsigned int div = 16 * (ubmr + 1);
1787 unsigned int rem = uartclk % div;
1788
1789 baud_raw = (uartclk / div) * mul;
1790 baud_raw += (rem * mul + div / 2) / div;
1791 *baud = (baud_raw + 50) / 100 * 100;
1792 }
1793
1794 if (*baud != baud_raw)
1795 pr_info("Console IMX rounded baud rate from %d to %d\n",
1796 baud_raw, *baud);
1797 }
1798}
1799
1800static int __init
1801imx_console_setup(struct console *co, char *options)
1802{
1803 struct imx_port *sport;
1804 int baud = 9600;
1805 int bits = 8;
1806 int parity = 'n';
1807 int flow = 'n';
1808 int retval;
1809
1810 /*
1811 * Check whether an invalid uart number has been specified, and
1812 * if so, search for the first available port that does have
1813 * console support.
1814 */
1815 if (co->index == -1 || co->index >= ARRAY_SIZE(imx_ports))
1816 co->index = 0;
1817 sport = imx_ports[co->index];
1818 if (sport == NULL)
1819 return -ENODEV;
1820
1821 /* For setting the registers, we only need to enable the ipg clock. */
1822 retval = clk_prepare_enable(sport->clk_ipg);
1823 if (retval)
1824 goto error_console;
1825
1826 if (options)
1827 uart_parse_options(options, &baud, &parity, &bits, &flow);
1828 else
1829 imx_console_get_options(sport, &baud, &parity, &bits);
1830
1831 imx_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT);
1832
1833 retval = uart_set_options(&sport->port, co, baud, parity, bits, flow);
1834
1835 clk_disable(sport->clk_ipg);
1836 if (retval) {
1837 clk_unprepare(sport->clk_ipg);
1838 goto error_console;
1839 }
1840
1841 retval = clk_prepare(sport->clk_per);
1842 if (retval)
1843 clk_disable_unprepare(sport->clk_ipg);
1844
1845error_console:
1846 return retval;
1847}
1848
1849static struct uart_driver imx_reg;
1850static struct console imx_console = {
1851 .name = DEV_NAME,
1852 .write = imx_console_write,
1853 .device = uart_console_device,
1854 .setup = imx_console_setup,
1855 .flags = CON_PRINTBUFFER,
1856 .index = -1,
1857 .data = &imx_reg,
1858};
1859
1860#define IMX_CONSOLE &imx_console
1861
1862#ifdef CONFIG_OF
1863static void imx_console_early_putchar(struct uart_port *port, int ch)
1864{
1865 while (readl_relaxed(port->membase + IMX21_UTS) & UTS_TXFULL)
1866 cpu_relax();
1867
1868 writel_relaxed(ch, port->membase + URTX0);
1869}
1870
1871static void imx_console_early_write(struct console *con, const char *s,
1872 unsigned count)
1873{
1874 struct earlycon_device *dev = con->data;
1875
1876 uart_console_write(&dev->port, s, count, imx_console_early_putchar);
1877}
1878
1879static int __init
1880imx_console_early_setup(struct earlycon_device *dev, const char *opt)
1881{
1882 if (!dev->port.membase)
1883 return -ENODEV;
1884
1885 dev->con->write = imx_console_early_write;
1886
1887 return 0;
1888}
1889OF_EARLYCON_DECLARE(ec_imx6q, "fsl,imx6q-uart", imx_console_early_setup);
1890OF_EARLYCON_DECLARE(ec_imx21, "fsl,imx21-uart", imx_console_early_setup);
1891#endif
1892
1893#else
1894#define IMX_CONSOLE NULL
1895#endif
1896
1897static struct uart_driver imx_reg = {
1898 .owner = THIS_MODULE,
1899 .driver_name = DRIVER_NAME,
1900 .dev_name = DEV_NAME,
1901 .major = SERIAL_IMX_MAJOR,
1902 .minor = MINOR_START,
1903 .nr = ARRAY_SIZE(imx_ports),
1904 .cons = IMX_CONSOLE,
1905};
1906
1907#ifdef CONFIG_OF
1908/*
1909 * This function returns 1 iff pdev isn't a device instatiated by dt, 0 iff it
1910 * could successfully get all information from dt or a negative errno.
1911 */
1912static int serial_imx_probe_dt(struct imx_port *sport,
1913 struct platform_device *pdev)
1914{
1915 struct device_node *np = pdev->dev.of_node;
1916 int ret;
1917
1918 sport->devdata = of_device_get_match_data(&pdev->dev);
1919 if (!sport->devdata)
1920 /* no device tree device */
1921 return 1;
1922
1923 ret = of_alias_get_id(np, "serial");
1924 if (ret < 0) {
1925 dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
1926 return ret;
1927 }
1928 sport->port.line = ret;
1929
1930 if (of_get_property(np, "fsl,uart-has-rtscts", NULL))
1931 sport->have_rtscts = 1;
1932
1933 if (of_get_property(np, "fsl,dte-mode", NULL))
1934 sport->dte_mode = 1;
1935
1936 return 0;
1937}
1938#else
1939static inline int serial_imx_probe_dt(struct imx_port *sport,
1940 struct platform_device *pdev)
1941{
1942 return 1;
1943}
1944#endif
1945
1946static void serial_imx_probe_pdata(struct imx_port *sport,
1947 struct platform_device *pdev)
1948{
1949 struct imxuart_platform_data *pdata = dev_get_platdata(&pdev->dev);
1950
1951 sport->port.line = pdev->id;
1952 sport->devdata = (struct imx_uart_data *) pdev->id_entry->driver_data;
1953
1954 if (!pdata)
1955 return;
1956
1957 if (pdata->flags & IMXUART_HAVE_RTSCTS)
1958 sport->have_rtscts = 1;
1959}
1960
1961static int serial_imx_probe(struct platform_device *pdev)
1962{
1963 struct imx_port *sport;
1964 void __iomem *base;
1965 int ret = 0, reg;
1966 struct resource *res;
1967 int txirq, rxirq, rtsirq;
1968
1969 sport = devm_kzalloc(&pdev->dev, sizeof(*sport), GFP_KERNEL);
1970 if (!sport)
1971 return -ENOMEM;
1972
1973 ret = serial_imx_probe_dt(sport, pdev);
1974 if (ret > 0)
1975 serial_imx_probe_pdata(sport, pdev);
1976 else if (ret < 0)
1977 return ret;
1978
1979 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1980 base = devm_ioremap_resource(&pdev->dev, res);
1981 if (IS_ERR(base))
1982 return PTR_ERR(base);
1983
1984 rxirq = platform_get_irq(pdev, 0);
1985 txirq = platform_get_irq(pdev, 1);
1986 rtsirq = platform_get_irq(pdev, 2);
1987
1988 sport->port.dev = &pdev->dev;
1989 sport->port.mapbase = res->start;
1990 sport->port.membase = base;
1991 sport->port.type = PORT_IMX,
1992 sport->port.iotype = UPIO_MEM;
1993 sport->port.irq = rxirq;
1994 sport->port.fifosize = 32;
1995 sport->port.ops = &imx_pops;
1996 sport->port.rs485_config = imx_rs485_config;
1997 sport->port.rs485.flags =
1998 SER_RS485_RTS_ON_SEND | SER_RS485_RX_DURING_TX;
1999 sport->port.flags = UPF_BOOT_AUTOCONF;
2000 init_timer(&sport->timer);
2001 sport->timer.function = imx_timeout;
2002 sport->timer.data = (unsigned long)sport;
2003
2004 sport->gpios = mctrl_gpio_init(&sport->port, 0);
2005 if (IS_ERR(sport->gpios))
2006 return PTR_ERR(sport->gpios);
2007
2008 sport->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
2009 if (IS_ERR(sport->clk_ipg)) {
2010 ret = PTR_ERR(sport->clk_ipg);
2011 dev_err(&pdev->dev, "failed to get ipg clk: %d\n", ret);
2012 return ret;
2013 }
2014
2015 sport->clk_per = devm_clk_get(&pdev->dev, "per");
2016 if (IS_ERR(sport->clk_per)) {
2017 ret = PTR_ERR(sport->clk_per);
2018 dev_err(&pdev->dev, "failed to get per clk: %d\n", ret);
2019 return ret;
2020 }
2021
2022 sport->port.uartclk = clk_get_rate(sport->clk_per);
2023
2024 /* For register access, we only need to enable the ipg clock. */
2025 ret = clk_prepare_enable(sport->clk_ipg);
2026 if (ret)
2027 return ret;
2028
2029 /* Disable interrupts before requesting them */
2030 reg = readl_relaxed(sport->port.membase + UCR1);
2031 reg &= ~(UCR1_ADEN | UCR1_TRDYEN | UCR1_IDEN | UCR1_RRDYEN |
2032 UCR1_TXMPTYEN | UCR1_RTSDEN);
2033 writel_relaxed(reg, sport->port.membase + UCR1);
2034
2035 clk_disable_unprepare(sport->clk_ipg);
2036
2037 /*
2038 * Allocate the IRQ(s) i.MX1 has three interrupts whereas later
2039 * chips only have one interrupt.
2040 */
2041 if (txirq > 0) {
2042 ret = devm_request_irq(&pdev->dev, rxirq, imx_rxint, 0,
2043 dev_name(&pdev->dev), sport);
2044 if (ret)
2045 return ret;
2046
2047 ret = devm_request_irq(&pdev->dev, txirq, imx_txint, 0,
2048 dev_name(&pdev->dev), sport);
2049 if (ret)
2050 return ret;
2051 } else {
2052 ret = devm_request_irq(&pdev->dev, rxirq, imx_int, 0,
2053 dev_name(&pdev->dev), sport);
2054 if (ret)
2055 return ret;
2056 }
2057
2058 imx_ports[sport->port.line] = sport;
2059
2060 platform_set_drvdata(pdev, sport);
2061
2062 return uart_add_one_port(&imx_reg, &sport->port);
2063}
2064
2065static int serial_imx_remove(struct platform_device *pdev)
2066{
2067 struct imx_port *sport = platform_get_drvdata(pdev);
2068
2069 return uart_remove_one_port(&imx_reg, &sport->port);
2070}
2071
2072static void serial_imx_restore_context(struct imx_port *sport)
2073{
2074 if (!sport->context_saved)
2075 return;
2076
2077 writel(sport->saved_reg[4], sport->port.membase + UFCR);
2078 writel(sport->saved_reg[5], sport->port.membase + UESC);
2079 writel(sport->saved_reg[6], sport->port.membase + UTIM);
2080 writel(sport->saved_reg[7], sport->port.membase + UBIR);
2081 writel(sport->saved_reg[8], sport->port.membase + UBMR);
2082 writel(sport->saved_reg[9], sport->port.membase + IMX21_UTS);
2083 writel(sport->saved_reg[0], sport->port.membase + UCR1);
2084 writel(sport->saved_reg[1] | UCR2_SRST, sport->port.membase + UCR2);
2085 writel(sport->saved_reg[2], sport->port.membase + UCR3);
2086 writel(sport->saved_reg[3], sport->port.membase + UCR4);
2087 sport->context_saved = false;
2088}
2089
2090static void serial_imx_save_context(struct imx_port *sport)
2091{
2092 /* Save necessary regs */
2093 sport->saved_reg[0] = readl(sport->port.membase + UCR1);
2094 sport->saved_reg[1] = readl(sport->port.membase + UCR2);
2095 sport->saved_reg[2] = readl(sport->port.membase + UCR3);
2096 sport->saved_reg[3] = readl(sport->port.membase + UCR4);
2097 sport->saved_reg[4] = readl(sport->port.membase + UFCR);
2098 sport->saved_reg[5] = readl(sport->port.membase + UESC);
2099 sport->saved_reg[6] = readl(sport->port.membase + UTIM);
2100 sport->saved_reg[7] = readl(sport->port.membase + UBIR);
2101 sport->saved_reg[8] = readl(sport->port.membase + UBMR);
2102 sport->saved_reg[9] = readl(sport->port.membase + IMX21_UTS);
2103 sport->context_saved = true;
2104}
2105
2106static void serial_imx_enable_wakeup(struct imx_port *sport, bool on)
2107{
2108 unsigned int val;
2109
2110 val = readl(sport->port.membase + UCR3);
2111 if (on)
2112 val |= UCR3_AWAKEN;
2113 else
2114 val &= ~UCR3_AWAKEN;
2115 writel(val, sport->port.membase + UCR3);
2116
2117 val = readl(sport->port.membase + UCR1);
2118 if (on)
2119 val |= UCR1_RTSDEN;
2120 else
2121 val &= ~UCR1_RTSDEN;
2122 writel(val, sport->port.membase + UCR1);
2123}
2124
2125static int imx_serial_port_suspend_noirq(struct device *dev)
2126{
2127 struct platform_device *pdev = to_platform_device(dev);
2128 struct imx_port *sport = platform_get_drvdata(pdev);
2129 int ret;
2130
2131 ret = clk_enable(sport->clk_ipg);
2132 if (ret)
2133 return ret;
2134
2135 serial_imx_save_context(sport);
2136
2137 clk_disable(sport->clk_ipg);
2138
2139 return 0;
2140}
2141
2142static int imx_serial_port_resume_noirq(struct device *dev)
2143{
2144 struct platform_device *pdev = to_platform_device(dev);
2145 struct imx_port *sport = platform_get_drvdata(pdev);
2146 int ret;
2147
2148 ret = clk_enable(sport->clk_ipg);
2149 if (ret)
2150 return ret;
2151
2152 serial_imx_restore_context(sport);
2153
2154 clk_disable(sport->clk_ipg);
2155
2156 return 0;
2157}
2158
2159static int imx_serial_port_suspend(struct device *dev)
2160{
2161 struct platform_device *pdev = to_platform_device(dev);
2162 struct imx_port *sport = platform_get_drvdata(pdev);
2163
2164 /* enable wakeup from i.MX UART */
2165 serial_imx_enable_wakeup(sport, true);
2166
2167 uart_suspend_port(&imx_reg, &sport->port);
2168
2169 /* Needed to enable clock in suspend_noirq */
2170 return clk_prepare(sport->clk_ipg);
2171}
2172
2173static int imx_serial_port_resume(struct device *dev)
2174{
2175 struct platform_device *pdev = to_platform_device(dev);
2176 struct imx_port *sport = platform_get_drvdata(pdev);
2177
2178 /* disable wakeup from i.MX UART */
2179 serial_imx_enable_wakeup(sport, false);
2180
2181 uart_resume_port(&imx_reg, &sport->port);
2182
2183 clk_unprepare(sport->clk_ipg);
2184
2185 return 0;
2186}
2187
2188static const struct dev_pm_ops imx_serial_port_pm_ops = {
2189 .suspend_noirq = imx_serial_port_suspend_noirq,
2190 .resume_noirq = imx_serial_port_resume_noirq,
2191 .suspend = imx_serial_port_suspend,
2192 .resume = imx_serial_port_resume,
2193};
2194
2195static struct platform_driver serial_imx_driver = {
2196 .probe = serial_imx_probe,
2197 .remove = serial_imx_remove,
2198
2199 .id_table = imx_uart_devtype,
2200 .driver = {
2201 .name = "imx-uart",
2202 .of_match_table = imx_uart_dt_ids,
2203 .pm = &imx_serial_port_pm_ops,
2204 },
2205};
2206
2207static int __init imx_serial_init(void)
2208{
2209 int ret = uart_register_driver(&imx_reg);
2210
2211 if (ret)
2212 return ret;
2213
2214 ret = platform_driver_register(&serial_imx_driver);
2215 if (ret != 0)
2216 uart_unregister_driver(&imx_reg);
2217
2218 return ret;
2219}
2220
2221static void __exit imx_serial_exit(void)
2222{
2223 platform_driver_unregister(&serial_imx_driver);
2224 uart_unregister_driver(&imx_reg);
2225}
2226
2227module_init(imx_serial_init);
2228module_exit(imx_serial_exit);
2229
2230MODULE_AUTHOR("Sascha Hauer");
2231MODULE_DESCRIPTION("IMX generic serial port driver");
2232MODULE_LICENSE("GPL");
2233MODULE_ALIAS("platform:imx-uart");