xref: /openbmc/linux/drivers/tty/serial/omap-serial.c (revision 7b6d864b)
1 /*
2  * Driver for OMAP-UART controller.
3  * Based on drivers/serial/8250.c
4  *
5  * Copyright (C) 2010 Texas Instruments.
6  *
7  * Authors:
8  *	Govindraj R	<govindraj.raja@ti.com>
9  *	Thara Gopinath	<thara@ti.com>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  *
16  * Note: This driver is made separate from 8250 driver as we cannot
17  * over load 8250 driver with omap platform specific configuration for
18  * features like DMA, it makes easier to implement features like DMA and
19  * hardware flow control and software flow control configuration with
20  * this driver as required for the omap-platform.
21  */
22 
23 #if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
24 #define SUPPORT_SYSRQ
25 #endif
26 
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/console.h>
30 #include <linux/serial_reg.h>
31 #include <linux/delay.h>
32 #include <linux/slab.h>
33 #include <linux/tty.h>
34 #include <linux/tty_flip.h>
35 #include <linux/platform_device.h>
36 #include <linux/io.h>
37 #include <linux/clk.h>
38 #include <linux/serial_core.h>
39 #include <linux/irq.h>
40 #include <linux/pm_runtime.h>
41 #include <linux/of.h>
42 #include <linux/gpio.h>
43 #include <linux/pinctrl/consumer.h>
44 #include <linux/platform_data/serial-omap.h>
45 
46 #define OMAP_MAX_HSUART_PORTS	6
47 
48 #define UART_BUILD_REVISION(x, y)	(((x) << 8) | (y))
49 
50 #define OMAP_UART_REV_42 0x0402
51 #define OMAP_UART_REV_46 0x0406
52 #define OMAP_UART_REV_52 0x0502
53 #define OMAP_UART_REV_63 0x0603
54 
55 #define UART_ERRATA_i202_MDR1_ACCESS	BIT(0)
56 #define UART_ERRATA_i291_DMA_FORCEIDLE	BIT(1)
57 
58 #define DEFAULT_CLK_SPEED 48000000 /* 48Mhz*/
59 
60 /* SCR register bitmasks */
61 #define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK		(1 << 7)
62 #define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK		(1 << 6)
63 #define OMAP_UART_SCR_TX_EMPTY			(1 << 3)
64 
65 /* FCR register bitmasks */
66 #define OMAP_UART_FCR_RX_FIFO_TRIG_MASK			(0x3 << 6)
67 #define OMAP_UART_FCR_TX_FIFO_TRIG_MASK			(0x3 << 4)
68 
69 /* MVR register bitmasks */
70 #define OMAP_UART_MVR_SCHEME_SHIFT	30
71 
72 #define OMAP_UART_LEGACY_MVR_MAJ_MASK	0xf0
73 #define OMAP_UART_LEGACY_MVR_MAJ_SHIFT	4
74 #define OMAP_UART_LEGACY_MVR_MIN_MASK	0x0f
75 
76 #define OMAP_UART_MVR_MAJ_MASK		0x700
77 #define OMAP_UART_MVR_MAJ_SHIFT		8
78 #define OMAP_UART_MVR_MIN_MASK		0x3f
79 
80 #define OMAP_UART_DMA_CH_FREE	-1
81 
82 #define MSR_SAVE_FLAGS		UART_MSR_ANY_DELTA
83 #define OMAP_MODE13X_SPEED	230400
84 
85 /* WER = 0x7F
86  * Enable module level wakeup in WER reg
87  */
88 #define OMAP_UART_WER_MOD_WKUP	0X7F
89 
90 /* Enable XON/XOFF flow control on output */
91 #define OMAP_UART_SW_TX		0x08
92 
93 /* Enable XON/XOFF flow control on input */
94 #define OMAP_UART_SW_RX		0x02
95 
96 #define OMAP_UART_SW_CLR	0xF0
97 
98 #define OMAP_UART_TCR_TRIG	0x0F
99 
100 struct uart_omap_dma {
101 	u8			uart_dma_tx;
102 	u8			uart_dma_rx;
103 	int			rx_dma_channel;
104 	int			tx_dma_channel;
105 	dma_addr_t		rx_buf_dma_phys;
106 	dma_addr_t		tx_buf_dma_phys;
107 	unsigned int		uart_base;
108 	/*
109 	 * Buffer for rx dma.It is not required for tx because the buffer
110 	 * comes from port structure.
111 	 */
112 	unsigned char		*rx_buf;
113 	unsigned int		prev_rx_dma_pos;
114 	int			tx_buf_size;
115 	int			tx_dma_used;
116 	int			rx_dma_used;
117 	spinlock_t		tx_lock;
118 	spinlock_t		rx_lock;
119 	/* timer to poll activity on rx dma */
120 	struct timer_list	rx_timer;
121 	unsigned int		rx_buf_size;
122 	unsigned int		rx_poll_rate;
123 	unsigned int		rx_timeout;
124 };
125 
126 struct uart_omap_port {
127 	struct uart_port	port;
128 	struct uart_omap_dma	uart_dma;
129 	struct device		*dev;
130 
131 	unsigned char		ier;
132 	unsigned char		lcr;
133 	unsigned char		mcr;
134 	unsigned char		fcr;
135 	unsigned char		efr;
136 	unsigned char		dll;
137 	unsigned char		dlh;
138 	unsigned char		mdr1;
139 	unsigned char		scr;
140 
141 	int			use_dma;
142 	/*
143 	 * Some bits in registers are cleared on a read, so they must
144 	 * be saved whenever the register is read but the bits will not
145 	 * be immediately processed.
146 	 */
147 	unsigned int		lsr_break_flag;
148 	unsigned char		msr_saved_flags;
149 	char			name[20];
150 	unsigned long		port_activity;
151 	int			context_loss_cnt;
152 	u32			errata;
153 	u8			wakeups_enabled;
154 
155 	int			DTR_gpio;
156 	int			DTR_inverted;
157 	int			DTR_active;
158 
159 	struct pm_qos_request	pm_qos_request;
160 	u32			latency;
161 	u32			calc_latency;
162 	struct work_struct	qos_work;
163 	struct pinctrl		*pins;
164 	bool			is_suspending;
165 };
166 
167 #define to_uart_omap_port(p)	((container_of((p), struct uart_omap_port, port)))
168 
169 static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
170 
171 /* Forward declaration of functions */
172 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
173 
174 static struct workqueue_struct *serial_omap_uart_wq;
175 
176 static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
177 {
178 	offset <<= up->port.regshift;
179 	return readw(up->port.membase + offset);
180 }
181 
182 static inline void serial_out(struct uart_omap_port *up, int offset, int value)
183 {
184 	offset <<= up->port.regshift;
185 	writew(value, up->port.membase + offset);
186 }
187 
188 static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
189 {
190 	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
191 	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
192 		       UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
193 	serial_out(up, UART_FCR, 0);
194 }
195 
196 static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
197 {
198 	struct omap_uart_port_info *pdata = up->dev->platform_data;
199 
200 	if (!pdata || !pdata->get_context_loss_count)
201 		return -EINVAL;
202 
203 	return pdata->get_context_loss_count(up->dev);
204 }
205 
206 static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
207 {
208 	struct omap_uart_port_info *pdata = up->dev->platform_data;
209 
210 	if (!pdata || !pdata->enable_wakeup)
211 		return;
212 
213 	pdata->enable_wakeup(up->dev, enable);
214 }
215 
216 /*
217  * serial_omap_baud_is_mode16 - check if baud rate is MODE16X
218  * @port: uart port info
219  * @baud: baudrate for which mode needs to be determined
220  *
221  * Returns true if baud rate is MODE16X and false if MODE13X
222  * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
223  * and Error Rates" determines modes not for all common baud rates.
224  * E.g. for 1000000 baud rate mode must be 16x, but according to that
225  * table it's determined as 13x.
226  */
227 static bool
228 serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
229 {
230 	unsigned int n13 = port->uartclk / (13 * baud);
231 	unsigned int n16 = port->uartclk / (16 * baud);
232 	int baudAbsDiff13 = baud - (port->uartclk / (13 * n13));
233 	int baudAbsDiff16 = baud - (port->uartclk / (16 * n16));
234 	if(baudAbsDiff13 < 0)
235 		baudAbsDiff13 = -baudAbsDiff13;
236 	if(baudAbsDiff16 < 0)
237 		baudAbsDiff16 = -baudAbsDiff16;
238 
239 	return (baudAbsDiff13 > baudAbsDiff16);
240 }
241 
242 /*
243  * serial_omap_get_divisor - calculate divisor value
244  * @port: uart port info
245  * @baud: baudrate for which divisor needs to be calculated.
246  */
247 static unsigned int
248 serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
249 {
250 	unsigned int divisor;
251 
252 	if (!serial_omap_baud_is_mode16(port, baud))
253 		divisor = 13;
254 	else
255 		divisor = 16;
256 	return port->uartclk/(baud * divisor);
257 }
258 
259 static void serial_omap_enable_ms(struct uart_port *port)
260 {
261 	struct uart_omap_port *up = to_uart_omap_port(port);
262 
263 	dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
264 
265 	pm_runtime_get_sync(up->dev);
266 	up->ier |= UART_IER_MSI;
267 	serial_out(up, UART_IER, up->ier);
268 	pm_runtime_mark_last_busy(up->dev);
269 	pm_runtime_put_autosuspend(up->dev);
270 }
271 
272 static void serial_omap_stop_tx(struct uart_port *port)
273 {
274 	struct uart_omap_port *up = to_uart_omap_port(port);
275 
276 	pm_runtime_get_sync(up->dev);
277 	if (up->ier & UART_IER_THRI) {
278 		up->ier &= ~UART_IER_THRI;
279 		serial_out(up, UART_IER, up->ier);
280 	}
281 
282 	pm_runtime_mark_last_busy(up->dev);
283 	pm_runtime_put_autosuspend(up->dev);
284 }
285 
286 static void serial_omap_stop_rx(struct uart_port *port)
287 {
288 	struct uart_omap_port *up = to_uart_omap_port(port);
289 
290 	pm_runtime_get_sync(up->dev);
291 	up->ier &= ~UART_IER_RLSI;
292 	up->port.read_status_mask &= ~UART_LSR_DR;
293 	serial_out(up, UART_IER, up->ier);
294 	pm_runtime_mark_last_busy(up->dev);
295 	pm_runtime_put_autosuspend(up->dev);
296 }
297 
298 static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
299 {
300 	struct circ_buf *xmit = &up->port.state->xmit;
301 	int count;
302 
303 	if (up->port.x_char) {
304 		serial_out(up, UART_TX, up->port.x_char);
305 		up->port.icount.tx++;
306 		up->port.x_char = 0;
307 		return;
308 	}
309 	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
310 		serial_omap_stop_tx(&up->port);
311 		return;
312 	}
313 	count = up->port.fifosize / 4;
314 	do {
315 		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
316 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
317 		up->port.icount.tx++;
318 		if (uart_circ_empty(xmit))
319 			break;
320 	} while (--count > 0);
321 
322 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) {
323 		spin_unlock(&up->port.lock);
324 		uart_write_wakeup(&up->port);
325 		spin_lock(&up->port.lock);
326 	}
327 
328 	if (uart_circ_empty(xmit))
329 		serial_omap_stop_tx(&up->port);
330 }
331 
332 static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
333 {
334 	if (!(up->ier & UART_IER_THRI)) {
335 		up->ier |= UART_IER_THRI;
336 		serial_out(up, UART_IER, up->ier);
337 	}
338 }
339 
340 static void serial_omap_start_tx(struct uart_port *port)
341 {
342 	struct uart_omap_port *up = to_uart_omap_port(port);
343 
344 	pm_runtime_get_sync(up->dev);
345 	serial_omap_enable_ier_thri(up);
346 	pm_runtime_mark_last_busy(up->dev);
347 	pm_runtime_put_autosuspend(up->dev);
348 }
349 
350 static void serial_omap_throttle(struct uart_port *port)
351 {
352 	struct uart_omap_port *up = to_uart_omap_port(port);
353 	unsigned long flags;
354 
355 	pm_runtime_get_sync(up->dev);
356 	spin_lock_irqsave(&up->port.lock, flags);
357 	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
358 	serial_out(up, UART_IER, up->ier);
359 	spin_unlock_irqrestore(&up->port.lock, flags);
360 	pm_runtime_mark_last_busy(up->dev);
361 	pm_runtime_put_autosuspend(up->dev);
362 }
363 
364 static void serial_omap_unthrottle(struct uart_port *port)
365 {
366 	struct uart_omap_port *up = to_uart_omap_port(port);
367 	unsigned long flags;
368 
369 	pm_runtime_get_sync(up->dev);
370 	spin_lock_irqsave(&up->port.lock, flags);
371 	up->ier |= UART_IER_RLSI | UART_IER_RDI;
372 	serial_out(up, UART_IER, up->ier);
373 	spin_unlock_irqrestore(&up->port.lock, flags);
374 	pm_runtime_mark_last_busy(up->dev);
375 	pm_runtime_put_autosuspend(up->dev);
376 }
377 
378 static unsigned int check_modem_status(struct uart_omap_port *up)
379 {
380 	unsigned int status;
381 
382 	status = serial_in(up, UART_MSR);
383 	status |= up->msr_saved_flags;
384 	up->msr_saved_flags = 0;
385 	if ((status & UART_MSR_ANY_DELTA) == 0)
386 		return status;
387 
388 	if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
389 	    up->port.state != NULL) {
390 		if (status & UART_MSR_TERI)
391 			up->port.icount.rng++;
392 		if (status & UART_MSR_DDSR)
393 			up->port.icount.dsr++;
394 		if (status & UART_MSR_DDCD)
395 			uart_handle_dcd_change
396 				(&up->port, status & UART_MSR_DCD);
397 		if (status & UART_MSR_DCTS)
398 			uart_handle_cts_change
399 				(&up->port, status & UART_MSR_CTS);
400 		wake_up_interruptible(&up->port.state->port.delta_msr_wait);
401 	}
402 
403 	return status;
404 }
405 
406 static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
407 {
408 	unsigned int flag;
409 	unsigned char ch = 0;
410 
411 	if (likely(lsr & UART_LSR_DR))
412 		ch = serial_in(up, UART_RX);
413 
414 	up->port.icount.rx++;
415 	flag = TTY_NORMAL;
416 
417 	if (lsr & UART_LSR_BI) {
418 		flag = TTY_BREAK;
419 		lsr &= ~(UART_LSR_FE | UART_LSR_PE);
420 		up->port.icount.brk++;
421 		/*
422 		 * We do the SysRQ and SAK checking
423 		 * here because otherwise the break
424 		 * may get masked by ignore_status_mask
425 		 * or read_status_mask.
426 		 */
427 		if (uart_handle_break(&up->port))
428 			return;
429 
430 	}
431 
432 	if (lsr & UART_LSR_PE) {
433 		flag = TTY_PARITY;
434 		up->port.icount.parity++;
435 	}
436 
437 	if (lsr & UART_LSR_FE) {
438 		flag = TTY_FRAME;
439 		up->port.icount.frame++;
440 	}
441 
442 	if (lsr & UART_LSR_OE)
443 		up->port.icount.overrun++;
444 
445 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
446 	if (up->port.line == up->port.cons->index) {
447 		/* Recover the break flag from console xmit */
448 		lsr |= up->lsr_break_flag;
449 	}
450 #endif
451 	uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag);
452 }
453 
454 static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
455 {
456 	unsigned char ch = 0;
457 	unsigned int flag;
458 
459 	if (!(lsr & UART_LSR_DR))
460 		return;
461 
462 	ch = serial_in(up, UART_RX);
463 	flag = TTY_NORMAL;
464 	up->port.icount.rx++;
465 
466 	if (uart_handle_sysrq_char(&up->port, ch))
467 		return;
468 
469 	uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
470 }
471 
472 /**
473  * serial_omap_irq() - This handles the interrupt from one port
474  * @irq: uart port irq number
475  * @dev_id: uart port info
476  */
477 static irqreturn_t serial_omap_irq(int irq, void *dev_id)
478 {
479 	struct uart_omap_port *up = dev_id;
480 	unsigned int iir, lsr;
481 	unsigned int type;
482 	irqreturn_t ret = IRQ_NONE;
483 	int max_count = 256;
484 
485 	spin_lock(&up->port.lock);
486 	pm_runtime_get_sync(up->dev);
487 
488 	do {
489 		iir = serial_in(up, UART_IIR);
490 		if (iir & UART_IIR_NO_INT)
491 			break;
492 
493 		ret = IRQ_HANDLED;
494 		lsr = serial_in(up, UART_LSR);
495 
496 		/* extract IRQ type from IIR register */
497 		type = iir & 0x3e;
498 
499 		switch (type) {
500 		case UART_IIR_MSI:
501 			check_modem_status(up);
502 			break;
503 		case UART_IIR_THRI:
504 			transmit_chars(up, lsr);
505 			break;
506 		case UART_IIR_RX_TIMEOUT:
507 			/* FALLTHROUGH */
508 		case UART_IIR_RDI:
509 			serial_omap_rdi(up, lsr);
510 			break;
511 		case UART_IIR_RLSI:
512 			serial_omap_rlsi(up, lsr);
513 			break;
514 		case UART_IIR_CTS_RTS_DSR:
515 			/* simply try again */
516 			break;
517 		case UART_IIR_XOFF:
518 			/* FALLTHROUGH */
519 		default:
520 			break;
521 		}
522 	} while (!(iir & UART_IIR_NO_INT) && max_count--);
523 
524 	spin_unlock(&up->port.lock);
525 
526 	tty_flip_buffer_push(&up->port.state->port);
527 
528 	pm_runtime_mark_last_busy(up->dev);
529 	pm_runtime_put_autosuspend(up->dev);
530 	up->port_activity = jiffies;
531 
532 	return ret;
533 }
534 
535 static unsigned int serial_omap_tx_empty(struct uart_port *port)
536 {
537 	struct uart_omap_port *up = to_uart_omap_port(port);
538 	unsigned long flags = 0;
539 	unsigned int ret = 0;
540 
541 	pm_runtime_get_sync(up->dev);
542 	dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
543 	spin_lock_irqsave(&up->port.lock, flags);
544 	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
545 	spin_unlock_irqrestore(&up->port.lock, flags);
546 	pm_runtime_mark_last_busy(up->dev);
547 	pm_runtime_put_autosuspend(up->dev);
548 	return ret;
549 }
550 
551 static unsigned int serial_omap_get_mctrl(struct uart_port *port)
552 {
553 	struct uart_omap_port *up = to_uart_omap_port(port);
554 	unsigned int status;
555 	unsigned int ret = 0;
556 
557 	pm_runtime_get_sync(up->dev);
558 	status = check_modem_status(up);
559 	pm_runtime_mark_last_busy(up->dev);
560 	pm_runtime_put_autosuspend(up->dev);
561 
562 	dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
563 
564 	if (status & UART_MSR_DCD)
565 		ret |= TIOCM_CAR;
566 	if (status & UART_MSR_RI)
567 		ret |= TIOCM_RNG;
568 	if (status & UART_MSR_DSR)
569 		ret |= TIOCM_DSR;
570 	if (status & UART_MSR_CTS)
571 		ret |= TIOCM_CTS;
572 	return ret;
573 }
574 
575 static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
576 {
577 	struct uart_omap_port *up = to_uart_omap_port(port);
578 	unsigned char mcr = 0, old_mcr;
579 
580 	dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
581 	if (mctrl & TIOCM_RTS)
582 		mcr |= UART_MCR_RTS;
583 	if (mctrl & TIOCM_DTR)
584 		mcr |= UART_MCR_DTR;
585 	if (mctrl & TIOCM_OUT1)
586 		mcr |= UART_MCR_OUT1;
587 	if (mctrl & TIOCM_OUT2)
588 		mcr |= UART_MCR_OUT2;
589 	if (mctrl & TIOCM_LOOP)
590 		mcr |= UART_MCR_LOOP;
591 
592 	pm_runtime_get_sync(up->dev);
593 	old_mcr = serial_in(up, UART_MCR);
594 	old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
595 		     UART_MCR_DTR | UART_MCR_RTS);
596 	up->mcr = old_mcr | mcr;
597 	serial_out(up, UART_MCR, up->mcr);
598 	pm_runtime_mark_last_busy(up->dev);
599 	pm_runtime_put_autosuspend(up->dev);
600 
601 	if (gpio_is_valid(up->DTR_gpio) &&
602 	    !!(mctrl & TIOCM_DTR) != up->DTR_active) {
603 		up->DTR_active = !up->DTR_active;
604 		if (gpio_cansleep(up->DTR_gpio))
605 			schedule_work(&up->qos_work);
606 		else
607 			gpio_set_value(up->DTR_gpio,
608 				       up->DTR_active != up->DTR_inverted);
609 	}
610 }
611 
612 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
613 {
614 	struct uart_omap_port *up = to_uart_omap_port(port);
615 	unsigned long flags = 0;
616 
617 	dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
618 	pm_runtime_get_sync(up->dev);
619 	spin_lock_irqsave(&up->port.lock, flags);
620 	if (break_state == -1)
621 		up->lcr |= UART_LCR_SBC;
622 	else
623 		up->lcr &= ~UART_LCR_SBC;
624 	serial_out(up, UART_LCR, up->lcr);
625 	spin_unlock_irqrestore(&up->port.lock, flags);
626 	pm_runtime_mark_last_busy(up->dev);
627 	pm_runtime_put_autosuspend(up->dev);
628 }
629 
630 static int serial_omap_startup(struct uart_port *port)
631 {
632 	struct uart_omap_port *up = to_uart_omap_port(port);
633 	unsigned long flags = 0;
634 	int retval;
635 
636 	/*
637 	 * Allocate the IRQ
638 	 */
639 	retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
640 				up->name, up);
641 	if (retval)
642 		return retval;
643 
644 	dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
645 
646 	pm_runtime_get_sync(up->dev);
647 	/*
648 	 * Clear the FIFO buffers and disable them.
649 	 * (they will be reenabled in set_termios())
650 	 */
651 	serial_omap_clear_fifos(up);
652 	/* For Hardware flow control */
653 	serial_out(up, UART_MCR, UART_MCR_RTS);
654 
655 	/*
656 	 * Clear the interrupt registers.
657 	 */
658 	(void) serial_in(up, UART_LSR);
659 	if (serial_in(up, UART_LSR) & UART_LSR_DR)
660 		(void) serial_in(up, UART_RX);
661 	(void) serial_in(up, UART_IIR);
662 	(void) serial_in(up, UART_MSR);
663 
664 	/*
665 	 * Now, initialize the UART
666 	 */
667 	serial_out(up, UART_LCR, UART_LCR_WLEN8);
668 	spin_lock_irqsave(&up->port.lock, flags);
669 	/*
670 	 * Most PC uarts need OUT2 raised to enable interrupts.
671 	 */
672 	up->port.mctrl |= TIOCM_OUT2;
673 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
674 	spin_unlock_irqrestore(&up->port.lock, flags);
675 
676 	up->msr_saved_flags = 0;
677 	/*
678 	 * Finally, enable interrupts. Note: Modem status interrupts
679 	 * are set via set_termios(), which will be occurring imminently
680 	 * anyway, so we don't enable them here.
681 	 */
682 	up->ier = UART_IER_RLSI | UART_IER_RDI;
683 	serial_out(up, UART_IER, up->ier);
684 
685 	/* Enable module level wake up */
686 	serial_out(up, UART_OMAP_WER, OMAP_UART_WER_MOD_WKUP);
687 
688 	pm_runtime_mark_last_busy(up->dev);
689 	pm_runtime_put_autosuspend(up->dev);
690 	up->port_activity = jiffies;
691 	return 0;
692 }
693 
694 static void serial_omap_shutdown(struct uart_port *port)
695 {
696 	struct uart_omap_port *up = to_uart_omap_port(port);
697 	unsigned long flags = 0;
698 
699 	dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
700 
701 	pm_runtime_get_sync(up->dev);
702 	/*
703 	 * Disable interrupts from this port
704 	 */
705 	up->ier = 0;
706 	serial_out(up, UART_IER, 0);
707 
708 	spin_lock_irqsave(&up->port.lock, flags);
709 	up->port.mctrl &= ~TIOCM_OUT2;
710 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
711 	spin_unlock_irqrestore(&up->port.lock, flags);
712 
713 	/*
714 	 * Disable break condition and FIFOs
715 	 */
716 	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
717 	serial_omap_clear_fifos(up);
718 
719 	/*
720 	 * Read data port to reset things, and then free the irq
721 	 */
722 	if (serial_in(up, UART_LSR) & UART_LSR_DR)
723 		(void) serial_in(up, UART_RX);
724 
725 	pm_runtime_mark_last_busy(up->dev);
726 	pm_runtime_put_autosuspend(up->dev);
727 	free_irq(up->port.irq, up);
728 }
729 
730 static void serial_omap_uart_qos_work(struct work_struct *work)
731 {
732 	struct uart_omap_port *up = container_of(work, struct uart_omap_port,
733 						qos_work);
734 
735 	pm_qos_update_request(&up->pm_qos_request, up->latency);
736 	if (gpio_is_valid(up->DTR_gpio))
737 		gpio_set_value_cansleep(up->DTR_gpio,
738 					up->DTR_active != up->DTR_inverted);
739 }
740 
741 static void
742 serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
743 			struct ktermios *old)
744 {
745 	struct uart_omap_port *up = to_uart_omap_port(port);
746 	unsigned char cval = 0;
747 	unsigned long flags = 0;
748 	unsigned int baud, quot;
749 
750 	switch (termios->c_cflag & CSIZE) {
751 	case CS5:
752 		cval = UART_LCR_WLEN5;
753 		break;
754 	case CS6:
755 		cval = UART_LCR_WLEN6;
756 		break;
757 	case CS7:
758 		cval = UART_LCR_WLEN7;
759 		break;
760 	default:
761 	case CS8:
762 		cval = UART_LCR_WLEN8;
763 		break;
764 	}
765 
766 	if (termios->c_cflag & CSTOPB)
767 		cval |= UART_LCR_STOP;
768 	if (termios->c_cflag & PARENB)
769 		cval |= UART_LCR_PARITY;
770 	if (!(termios->c_cflag & PARODD))
771 		cval |= UART_LCR_EPAR;
772 	if (termios->c_cflag & CMSPAR)
773 		cval |= UART_LCR_SPAR;
774 
775 	/*
776 	 * Ask the core to calculate the divisor for us.
777 	 */
778 
779 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
780 	quot = serial_omap_get_divisor(port, baud);
781 
782 	/* calculate wakeup latency constraint */
783 	up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
784 	up->latency = up->calc_latency;
785 	schedule_work(&up->qos_work);
786 
787 	up->dll = quot & 0xff;
788 	up->dlh = quot >> 8;
789 	up->mdr1 = UART_OMAP_MDR1_DISABLE;
790 
791 	up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
792 			UART_FCR_ENABLE_FIFO;
793 
794 	/*
795 	 * Ok, we're now changing the port state. Do it with
796 	 * interrupts disabled.
797 	 */
798 	pm_runtime_get_sync(up->dev);
799 	spin_lock_irqsave(&up->port.lock, flags);
800 
801 	/*
802 	 * Update the per-port timeout.
803 	 */
804 	uart_update_timeout(port, termios->c_cflag, baud);
805 
806 	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
807 	if (termios->c_iflag & INPCK)
808 		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
809 	if (termios->c_iflag & (BRKINT | PARMRK))
810 		up->port.read_status_mask |= UART_LSR_BI;
811 
812 	/*
813 	 * Characters to ignore
814 	 */
815 	up->port.ignore_status_mask = 0;
816 	if (termios->c_iflag & IGNPAR)
817 		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
818 	if (termios->c_iflag & IGNBRK) {
819 		up->port.ignore_status_mask |= UART_LSR_BI;
820 		/*
821 		 * If we're ignoring parity and break indicators,
822 		 * ignore overruns too (for real raw support).
823 		 */
824 		if (termios->c_iflag & IGNPAR)
825 			up->port.ignore_status_mask |= UART_LSR_OE;
826 	}
827 
828 	/*
829 	 * ignore all characters if CREAD is not set
830 	 */
831 	if ((termios->c_cflag & CREAD) == 0)
832 		up->port.ignore_status_mask |= UART_LSR_DR;
833 
834 	/*
835 	 * Modem status interrupts
836 	 */
837 	up->ier &= ~UART_IER_MSI;
838 	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
839 		up->ier |= UART_IER_MSI;
840 	serial_out(up, UART_IER, up->ier);
841 	serial_out(up, UART_LCR, cval);		/* reset DLAB */
842 	up->lcr = cval;
843 	up->scr = 0;
844 
845 	/* FIFOs and DMA Settings */
846 
847 	/* FCR can be changed only when the
848 	 * baud clock is not running
849 	 * DLL_REG and DLH_REG set to 0.
850 	 */
851 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
852 	serial_out(up, UART_DLL, 0);
853 	serial_out(up, UART_DLM, 0);
854 	serial_out(up, UART_LCR, 0);
855 
856 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
857 
858 	up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
859 	up->efr &= ~UART_EFR_SCD;
860 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
861 
862 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
863 	up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
864 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
865 	/* FIFO ENABLE, DMA MODE */
866 
867 	up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
868 	/*
869 	 * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
870 	 * sets Enables the granularity of 1 for TRIGGER RX
871 	 * level. Along with setting RX FIFO trigger level
872 	 * to 1 (as noted below, 16 characters) and TLR[3:0]
873 	 * to zero this will result RX FIFO threshold level
874 	 * to 1 character, instead of 16 as noted in comment
875 	 * below.
876 	 */
877 
878 	/* Set receive FIFO threshold to 16 characters and
879 	 * transmit FIFO threshold to 16 spaces
880 	 */
881 	up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
882 	up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
883 	up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
884 		UART_FCR_ENABLE_FIFO;
885 
886 	serial_out(up, UART_FCR, up->fcr);
887 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
888 
889 	serial_out(up, UART_OMAP_SCR, up->scr);
890 
891 	/* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
892 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
893 	serial_out(up, UART_MCR, up->mcr);
894 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
895 	serial_out(up, UART_EFR, up->efr);
896 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
897 
898 	/* Protocol, Baud Rate, and Interrupt Settings */
899 
900 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
901 		serial_omap_mdr1_errataset(up, up->mdr1);
902 	else
903 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
904 
905 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
906 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
907 
908 	serial_out(up, UART_LCR, 0);
909 	serial_out(up, UART_IER, 0);
910 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
911 
912 	serial_out(up, UART_DLL, up->dll);	/* LS of divisor */
913 	serial_out(up, UART_DLM, up->dlh);	/* MS of divisor */
914 
915 	serial_out(up, UART_LCR, 0);
916 	serial_out(up, UART_IER, up->ier);
917 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
918 
919 	serial_out(up, UART_EFR, up->efr);
920 	serial_out(up, UART_LCR, cval);
921 
922 	if (!serial_omap_baud_is_mode16(port, baud))
923 		up->mdr1 = UART_OMAP_MDR1_13X_MODE;
924 	else
925 		up->mdr1 = UART_OMAP_MDR1_16X_MODE;
926 
927 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
928 		serial_omap_mdr1_errataset(up, up->mdr1);
929 	else
930 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
931 
932 	/* Configure flow control */
933 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
934 
935 	/* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
936 	serial_out(up, UART_XON1, termios->c_cc[VSTART]);
937 	serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
938 
939 	/* Enable access to TCR/TLR */
940 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
941 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
942 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
943 
944 	serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
945 
946 	if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
947 		/* Enable AUTORTS and AUTOCTS */
948 		up->efr |= UART_EFR_CTS | UART_EFR_RTS;
949 
950 		/* Ensure MCR RTS is asserted */
951 		up->mcr |= UART_MCR_RTS;
952 	} else {
953 		/* Disable AUTORTS and AUTOCTS */
954 		up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
955 	}
956 
957 	if (up->port.flags & UPF_SOFT_FLOW) {
958 		/* clear SW control mode bits */
959 		up->efr &= OMAP_UART_SW_CLR;
960 
961 		/*
962 		 * IXON Flag:
963 		 * Enable XON/XOFF flow control on input.
964 		 * Receiver compares XON1, XOFF1.
965 		 */
966 		if (termios->c_iflag & IXON)
967 			up->efr |= OMAP_UART_SW_RX;
968 
969 		/*
970 		 * IXOFF Flag:
971 		 * Enable XON/XOFF flow control on output.
972 		 * Transmit XON1, XOFF1
973 		 */
974 		if (termios->c_iflag & IXOFF)
975 			up->efr |= OMAP_UART_SW_TX;
976 
977 		/*
978 		 * IXANY Flag:
979 		 * Enable any character to restart output.
980 		 * Operation resumes after receiving any
981 		 * character after recognition of the XOFF character
982 		 */
983 		if (termios->c_iflag & IXANY)
984 			up->mcr |= UART_MCR_XONANY;
985 		else
986 			up->mcr &= ~UART_MCR_XONANY;
987 	}
988 	serial_out(up, UART_MCR, up->mcr);
989 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
990 	serial_out(up, UART_EFR, up->efr);
991 	serial_out(up, UART_LCR, up->lcr);
992 
993 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
994 
995 	spin_unlock_irqrestore(&up->port.lock, flags);
996 	pm_runtime_mark_last_busy(up->dev);
997 	pm_runtime_put_autosuspend(up->dev);
998 	dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
999 }
1000 
1001 static int serial_omap_set_wake(struct uart_port *port, unsigned int state)
1002 {
1003 	struct uart_omap_port *up = to_uart_omap_port(port);
1004 
1005 	serial_omap_enable_wakeup(up, state);
1006 
1007 	return 0;
1008 }
1009 
1010 static void
1011 serial_omap_pm(struct uart_port *port, unsigned int state,
1012 	       unsigned int oldstate)
1013 {
1014 	struct uart_omap_port *up = to_uart_omap_port(port);
1015 	unsigned char efr;
1016 
1017 	dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
1018 
1019 	pm_runtime_get_sync(up->dev);
1020 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1021 	efr = serial_in(up, UART_EFR);
1022 	serial_out(up, UART_EFR, efr | UART_EFR_ECB);
1023 	serial_out(up, UART_LCR, 0);
1024 
1025 	serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
1026 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1027 	serial_out(up, UART_EFR, efr);
1028 	serial_out(up, UART_LCR, 0);
1029 
1030 	if (!device_may_wakeup(up->dev)) {
1031 		if (!state)
1032 			pm_runtime_forbid(up->dev);
1033 		else
1034 			pm_runtime_allow(up->dev);
1035 	}
1036 
1037 	pm_runtime_mark_last_busy(up->dev);
1038 	pm_runtime_put_autosuspend(up->dev);
1039 }
1040 
1041 static void serial_omap_release_port(struct uart_port *port)
1042 {
1043 	dev_dbg(port->dev, "serial_omap_release_port+\n");
1044 }
1045 
1046 static int serial_omap_request_port(struct uart_port *port)
1047 {
1048 	dev_dbg(port->dev, "serial_omap_request_port+\n");
1049 	return 0;
1050 }
1051 
1052 static void serial_omap_config_port(struct uart_port *port, int flags)
1053 {
1054 	struct uart_omap_port *up = to_uart_omap_port(port);
1055 
1056 	dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
1057 							up->port.line);
1058 	up->port.type = PORT_OMAP;
1059 	up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
1060 }
1061 
1062 static int
1063 serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
1064 {
1065 	/* we don't want the core code to modify any port params */
1066 	dev_dbg(port->dev, "serial_omap_verify_port+\n");
1067 	return -EINVAL;
1068 }
1069 
1070 static const char *
1071 serial_omap_type(struct uart_port *port)
1072 {
1073 	struct uart_omap_port *up = to_uart_omap_port(port);
1074 
1075 	dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
1076 	return up->name;
1077 }
1078 
1079 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1080 
1081 static inline void wait_for_xmitr(struct uart_omap_port *up)
1082 {
1083 	unsigned int status, tmout = 10000;
1084 
1085 	/* Wait up to 10ms for the character(s) to be sent. */
1086 	do {
1087 		status = serial_in(up, UART_LSR);
1088 
1089 		if (status & UART_LSR_BI)
1090 			up->lsr_break_flag = UART_LSR_BI;
1091 
1092 		if (--tmout == 0)
1093 			break;
1094 		udelay(1);
1095 	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
1096 
1097 	/* Wait up to 1s for flow control if necessary */
1098 	if (up->port.flags & UPF_CONS_FLOW) {
1099 		tmout = 1000000;
1100 		for (tmout = 1000000; tmout; tmout--) {
1101 			unsigned int msr = serial_in(up, UART_MSR);
1102 
1103 			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1104 			if (msr & UART_MSR_CTS)
1105 				break;
1106 
1107 			udelay(1);
1108 		}
1109 	}
1110 }
1111 
1112 #ifdef CONFIG_CONSOLE_POLL
1113 
1114 static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
1115 {
1116 	struct uart_omap_port *up = to_uart_omap_port(port);
1117 
1118 	pm_runtime_get_sync(up->dev);
1119 	wait_for_xmitr(up);
1120 	serial_out(up, UART_TX, ch);
1121 	pm_runtime_mark_last_busy(up->dev);
1122 	pm_runtime_put_autosuspend(up->dev);
1123 }
1124 
1125 static int serial_omap_poll_get_char(struct uart_port *port)
1126 {
1127 	struct uart_omap_port *up = to_uart_omap_port(port);
1128 	unsigned int status;
1129 
1130 	pm_runtime_get_sync(up->dev);
1131 	status = serial_in(up, UART_LSR);
1132 	if (!(status & UART_LSR_DR)) {
1133 		status = NO_POLL_CHAR;
1134 		goto out;
1135 	}
1136 
1137 	status = serial_in(up, UART_RX);
1138 
1139 out:
1140 	pm_runtime_mark_last_busy(up->dev);
1141 	pm_runtime_put_autosuspend(up->dev);
1142 
1143 	return status;
1144 }
1145 
1146 #endif /* CONFIG_CONSOLE_POLL */
1147 
1148 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
1149 
1150 static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
1151 
1152 static struct uart_driver serial_omap_reg;
1153 
1154 static void serial_omap_console_putchar(struct uart_port *port, int ch)
1155 {
1156 	struct uart_omap_port *up = to_uart_omap_port(port);
1157 
1158 	wait_for_xmitr(up);
1159 	serial_out(up, UART_TX, ch);
1160 }
1161 
1162 static void
1163 serial_omap_console_write(struct console *co, const char *s,
1164 		unsigned int count)
1165 {
1166 	struct uart_omap_port *up = serial_omap_console_ports[co->index];
1167 	unsigned long flags;
1168 	unsigned int ier;
1169 	int locked = 1;
1170 
1171 	pm_runtime_get_sync(up->dev);
1172 
1173 	local_irq_save(flags);
1174 	if (up->port.sysrq)
1175 		locked = 0;
1176 	else if (oops_in_progress)
1177 		locked = spin_trylock(&up->port.lock);
1178 	else
1179 		spin_lock(&up->port.lock);
1180 
1181 	/*
1182 	 * First save the IER then disable the interrupts
1183 	 */
1184 	ier = serial_in(up, UART_IER);
1185 	serial_out(up, UART_IER, 0);
1186 
1187 	uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1188 
1189 	/*
1190 	 * Finally, wait for transmitter to become empty
1191 	 * and restore the IER
1192 	 */
1193 	wait_for_xmitr(up);
1194 	serial_out(up, UART_IER, ier);
1195 	/*
1196 	 * The receive handling will happen properly because the
1197 	 * receive ready bit will still be set; it is not cleared
1198 	 * on read.  However, modem control will not, we must
1199 	 * call it if we have saved something in the saved flags
1200 	 * while processing with interrupts off.
1201 	 */
1202 	if (up->msr_saved_flags)
1203 		check_modem_status(up);
1204 
1205 	pm_runtime_mark_last_busy(up->dev);
1206 	pm_runtime_put_autosuspend(up->dev);
1207 	if (locked)
1208 		spin_unlock(&up->port.lock);
1209 	local_irq_restore(flags);
1210 }
1211 
1212 static int __init
1213 serial_omap_console_setup(struct console *co, char *options)
1214 {
1215 	struct uart_omap_port *up;
1216 	int baud = 115200;
1217 	int bits = 8;
1218 	int parity = 'n';
1219 	int flow = 'n';
1220 
1221 	if (serial_omap_console_ports[co->index] == NULL)
1222 		return -ENODEV;
1223 	up = serial_omap_console_ports[co->index];
1224 
1225 	if (options)
1226 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1227 
1228 	return uart_set_options(&up->port, co, baud, parity, bits, flow);
1229 }
1230 
1231 static struct console serial_omap_console = {
1232 	.name		= OMAP_SERIAL_NAME,
1233 	.write		= serial_omap_console_write,
1234 	.device		= uart_console_device,
1235 	.setup		= serial_omap_console_setup,
1236 	.flags		= CON_PRINTBUFFER,
1237 	.index		= -1,
1238 	.data		= &serial_omap_reg,
1239 };
1240 
1241 static void serial_omap_add_console_port(struct uart_omap_port *up)
1242 {
1243 	serial_omap_console_ports[up->port.line] = up;
1244 }
1245 
1246 #define OMAP_CONSOLE	(&serial_omap_console)
1247 
1248 #else
1249 
1250 #define OMAP_CONSOLE	NULL
1251 
1252 static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1253 {}
1254 
1255 #endif
1256 
1257 static struct uart_ops serial_omap_pops = {
1258 	.tx_empty	= serial_omap_tx_empty,
1259 	.set_mctrl	= serial_omap_set_mctrl,
1260 	.get_mctrl	= serial_omap_get_mctrl,
1261 	.stop_tx	= serial_omap_stop_tx,
1262 	.start_tx	= serial_omap_start_tx,
1263 	.throttle	= serial_omap_throttle,
1264 	.unthrottle	= serial_omap_unthrottle,
1265 	.stop_rx	= serial_omap_stop_rx,
1266 	.enable_ms	= serial_omap_enable_ms,
1267 	.break_ctl	= serial_omap_break_ctl,
1268 	.startup	= serial_omap_startup,
1269 	.shutdown	= serial_omap_shutdown,
1270 	.set_termios	= serial_omap_set_termios,
1271 	.pm		= serial_omap_pm,
1272 	.set_wake	= serial_omap_set_wake,
1273 	.type		= serial_omap_type,
1274 	.release_port	= serial_omap_release_port,
1275 	.request_port	= serial_omap_request_port,
1276 	.config_port	= serial_omap_config_port,
1277 	.verify_port	= serial_omap_verify_port,
1278 #ifdef CONFIG_CONSOLE_POLL
1279 	.poll_put_char  = serial_omap_poll_put_char,
1280 	.poll_get_char  = serial_omap_poll_get_char,
1281 #endif
1282 };
1283 
1284 static struct uart_driver serial_omap_reg = {
1285 	.owner		= THIS_MODULE,
1286 	.driver_name	= "OMAP-SERIAL",
1287 	.dev_name	= OMAP_SERIAL_NAME,
1288 	.nr		= OMAP_MAX_HSUART_PORTS,
1289 	.cons		= OMAP_CONSOLE,
1290 };
1291 
1292 #ifdef CONFIG_PM_SLEEP
1293 static int serial_omap_prepare(struct device *dev)
1294 {
1295 	struct uart_omap_port *up = dev_get_drvdata(dev);
1296 
1297 	up->is_suspending = true;
1298 
1299 	return 0;
1300 }
1301 
1302 static void serial_omap_complete(struct device *dev)
1303 {
1304 	struct uart_omap_port *up = dev_get_drvdata(dev);
1305 
1306 	up->is_suspending = false;
1307 }
1308 
1309 static int serial_omap_suspend(struct device *dev)
1310 {
1311 	struct uart_omap_port *up = dev_get_drvdata(dev);
1312 
1313 	uart_suspend_port(&serial_omap_reg, &up->port);
1314 	flush_work(&up->qos_work);
1315 
1316 	return 0;
1317 }
1318 
1319 static int serial_omap_resume(struct device *dev)
1320 {
1321 	struct uart_omap_port *up = dev_get_drvdata(dev);
1322 
1323 	uart_resume_port(&serial_omap_reg, &up->port);
1324 
1325 	return 0;
1326 }
1327 #else
1328 #define serial_omap_prepare NULL
1329 #define serial_omap_complete NULL
1330 #endif /* CONFIG_PM_SLEEP */
1331 
1332 static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
1333 {
1334 	u32 mvr, scheme;
1335 	u16 revision, major, minor;
1336 
1337 	mvr = serial_in(up, UART_OMAP_MVER);
1338 
1339 	/* Check revision register scheme */
1340 	scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
1341 
1342 	switch (scheme) {
1343 	case 0: /* Legacy Scheme: OMAP2/3 */
1344 		/* MINOR_REV[0:4], MAJOR_REV[4:7] */
1345 		major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
1346 					OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
1347 		minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
1348 		break;
1349 	case 1:
1350 		/* New Scheme: OMAP4+ */
1351 		/* MINOR_REV[0:5], MAJOR_REV[8:10] */
1352 		major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
1353 					OMAP_UART_MVR_MAJ_SHIFT;
1354 		minor = (mvr & OMAP_UART_MVR_MIN_MASK);
1355 		break;
1356 	default:
1357 		dev_warn(up->dev,
1358 			"Unknown %s revision, defaulting to highest\n",
1359 			up->name);
1360 		/* highest possible revision */
1361 		major = 0xff;
1362 		minor = 0xff;
1363 	}
1364 
1365 	/* normalize revision for the driver */
1366 	revision = UART_BUILD_REVISION(major, minor);
1367 
1368 	switch (revision) {
1369 	case OMAP_UART_REV_46:
1370 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1371 				UART_ERRATA_i291_DMA_FORCEIDLE);
1372 		break;
1373 	case OMAP_UART_REV_52:
1374 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1375 				UART_ERRATA_i291_DMA_FORCEIDLE);
1376 		break;
1377 	case OMAP_UART_REV_63:
1378 		up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
1379 		break;
1380 	default:
1381 		break;
1382 	}
1383 }
1384 
1385 static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1386 {
1387 	struct omap_uart_port_info *omap_up_info;
1388 
1389 	omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1390 	if (!omap_up_info)
1391 		return NULL; /* out of memory */
1392 
1393 	of_property_read_u32(dev->of_node, "clock-frequency",
1394 					 &omap_up_info->uartclk);
1395 	return omap_up_info;
1396 }
1397 
1398 static int serial_omap_probe(struct platform_device *pdev)
1399 {
1400 	struct uart_omap_port	*up;
1401 	struct resource		*mem, *irq;
1402 	struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data;
1403 	int ret;
1404 
1405 	if (pdev->dev.of_node)
1406 		omap_up_info = of_get_uart_port_info(&pdev->dev);
1407 
1408 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1409 	if (!mem) {
1410 		dev_err(&pdev->dev, "no mem resource?\n");
1411 		return -ENODEV;
1412 	}
1413 
1414 	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1415 	if (!irq) {
1416 		dev_err(&pdev->dev, "no irq resource?\n");
1417 		return -ENODEV;
1418 	}
1419 
1420 	if (!devm_request_mem_region(&pdev->dev, mem->start, resource_size(mem),
1421 				pdev->dev.driver->name)) {
1422 		dev_err(&pdev->dev, "memory region already claimed\n");
1423 		return -EBUSY;
1424 	}
1425 
1426 	if (gpio_is_valid(omap_up_info->DTR_gpio) &&
1427 	    omap_up_info->DTR_present) {
1428 		ret = gpio_request(omap_up_info->DTR_gpio, "omap-serial");
1429 		if (ret < 0)
1430 			return ret;
1431 		ret = gpio_direction_output(omap_up_info->DTR_gpio,
1432 					    omap_up_info->DTR_inverted);
1433 		if (ret < 0)
1434 			return ret;
1435 	}
1436 
1437 	up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
1438 	if (!up)
1439 		return -ENOMEM;
1440 
1441 	if (gpio_is_valid(omap_up_info->DTR_gpio) &&
1442 	    omap_up_info->DTR_present) {
1443 		up->DTR_gpio = omap_up_info->DTR_gpio;
1444 		up->DTR_inverted = omap_up_info->DTR_inverted;
1445 	} else
1446 		up->DTR_gpio = -EINVAL;
1447 	up->DTR_active = 0;
1448 
1449 	up->dev = &pdev->dev;
1450 	up->port.dev = &pdev->dev;
1451 	up->port.type = PORT_OMAP;
1452 	up->port.iotype = UPIO_MEM;
1453 	up->port.irq = irq->start;
1454 
1455 	up->port.regshift = 2;
1456 	up->port.fifosize = 64;
1457 	up->port.ops = &serial_omap_pops;
1458 
1459 	if (pdev->dev.of_node)
1460 		up->port.line = of_alias_get_id(pdev->dev.of_node, "serial");
1461 	else
1462 		up->port.line = pdev->id;
1463 
1464 	if (up->port.line < 0) {
1465 		dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1466 								up->port.line);
1467 		ret = -ENODEV;
1468 		goto err_port_line;
1469 	}
1470 
1471 	up->pins = devm_pinctrl_get_select_default(&pdev->dev);
1472 	if (IS_ERR(up->pins)) {
1473 		dev_warn(&pdev->dev, "did not get pins for uart%i error: %li\n",
1474 			 up->port.line, PTR_ERR(up->pins));
1475 		up->pins = NULL;
1476 	}
1477 
1478 	sprintf(up->name, "OMAP UART%d", up->port.line);
1479 	up->port.mapbase = mem->start;
1480 	up->port.membase = devm_ioremap(&pdev->dev, mem->start,
1481 						resource_size(mem));
1482 	if (!up->port.membase) {
1483 		dev_err(&pdev->dev, "can't ioremap UART\n");
1484 		ret = -ENOMEM;
1485 		goto err_ioremap;
1486 	}
1487 
1488 	up->port.flags = omap_up_info->flags;
1489 	up->port.uartclk = omap_up_info->uartclk;
1490 	if (!up->port.uartclk) {
1491 		up->port.uartclk = DEFAULT_CLK_SPEED;
1492 		dev_warn(&pdev->dev, "No clock speed specified: using default:"
1493 						"%d\n", DEFAULT_CLK_SPEED);
1494 	}
1495 
1496 	up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1497 	up->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1498 	pm_qos_add_request(&up->pm_qos_request,
1499 		PM_QOS_CPU_DMA_LATENCY, up->latency);
1500 	serial_omap_uart_wq = create_singlethread_workqueue(up->name);
1501 	INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1502 
1503 	platform_set_drvdata(pdev, up);
1504 	pm_runtime_enable(&pdev->dev);
1505 	if (omap_up_info->autosuspend_timeout == 0)
1506 		omap_up_info->autosuspend_timeout = -1;
1507 	device_init_wakeup(up->dev, true);
1508 	pm_runtime_use_autosuspend(&pdev->dev);
1509 	pm_runtime_set_autosuspend_delay(&pdev->dev,
1510 			omap_up_info->autosuspend_timeout);
1511 
1512 	pm_runtime_irq_safe(&pdev->dev);
1513 	pm_runtime_get_sync(&pdev->dev);
1514 
1515 	omap_serial_fill_features_erratas(up);
1516 
1517 	ui[up->port.line] = up;
1518 	serial_omap_add_console_port(up);
1519 
1520 	ret = uart_add_one_port(&serial_omap_reg, &up->port);
1521 	if (ret != 0)
1522 		goto err_add_port;
1523 
1524 	pm_runtime_mark_last_busy(up->dev);
1525 	pm_runtime_put_autosuspend(up->dev);
1526 	return 0;
1527 
1528 err_add_port:
1529 	pm_runtime_put(&pdev->dev);
1530 	pm_runtime_disable(&pdev->dev);
1531 err_ioremap:
1532 err_port_line:
1533 	dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n",
1534 				pdev->id, __func__, ret);
1535 	return ret;
1536 }
1537 
1538 static int serial_omap_remove(struct platform_device *dev)
1539 {
1540 	struct uart_omap_port *up = platform_get_drvdata(dev);
1541 
1542 	pm_runtime_put_sync(up->dev);
1543 	pm_runtime_disable(up->dev);
1544 	uart_remove_one_port(&serial_omap_reg, &up->port);
1545 	pm_qos_remove_request(&up->pm_qos_request);
1546 
1547 	return 0;
1548 }
1549 
1550 /*
1551  * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1552  * The access to uart register after MDR1 Access
1553  * causes UART to corrupt data.
1554  *
1555  * Need a delay =
1556  * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1557  * give 10 times as much
1558  */
1559 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1560 {
1561 	u8 timeout = 255;
1562 
1563 	serial_out(up, UART_OMAP_MDR1, mdr1);
1564 	udelay(2);
1565 	serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1566 			UART_FCR_CLEAR_RCVR);
1567 	/*
1568 	 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1569 	 * TX_FIFO_E bit is 1.
1570 	 */
1571 	while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1572 				(UART_LSR_THRE | UART_LSR_DR))) {
1573 		timeout--;
1574 		if (!timeout) {
1575 			/* Should *never* happen. we warn and carry on */
1576 			dev_crit(up->dev, "Errata i202: timedout %x\n",
1577 						serial_in(up, UART_LSR));
1578 			break;
1579 		}
1580 		udelay(1);
1581 	}
1582 }
1583 
1584 #ifdef CONFIG_PM_RUNTIME
1585 static void serial_omap_restore_context(struct uart_omap_port *up)
1586 {
1587 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1588 		serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1589 	else
1590 		serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1591 
1592 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1593 	serial_out(up, UART_EFR, UART_EFR_ECB);
1594 	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1595 	serial_out(up, UART_IER, 0x0);
1596 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1597 	serial_out(up, UART_DLL, up->dll);
1598 	serial_out(up, UART_DLM, up->dlh);
1599 	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1600 	serial_out(up, UART_IER, up->ier);
1601 	serial_out(up, UART_FCR, up->fcr);
1602 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1603 	serial_out(up, UART_MCR, up->mcr);
1604 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1605 	serial_out(up, UART_OMAP_SCR, up->scr);
1606 	serial_out(up, UART_EFR, up->efr);
1607 	serial_out(up, UART_LCR, up->lcr);
1608 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1609 		serial_omap_mdr1_errataset(up, up->mdr1);
1610 	else
1611 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1612 }
1613 
1614 static int serial_omap_runtime_suspend(struct device *dev)
1615 {
1616 	struct uart_omap_port *up = dev_get_drvdata(dev);
1617 
1618 	if (!up)
1619 		return -EINVAL;
1620 
1621 	/*
1622 	* When using 'no_console_suspend', the console UART must not be
1623 	* suspended. Since driver suspend is managed by runtime suspend,
1624 	* preventing runtime suspend (by returning error) will keep device
1625 	* active during suspend.
1626 	*/
1627 	if (up->is_suspending && !console_suspend_enabled &&
1628 	    uart_console(&up->port))
1629 		return -EBUSY;
1630 
1631 	up->context_loss_cnt = serial_omap_get_context_loss_count(up);
1632 
1633 	if (device_may_wakeup(dev)) {
1634 		if (!up->wakeups_enabled) {
1635 			serial_omap_enable_wakeup(up, true);
1636 			up->wakeups_enabled = true;
1637 		}
1638 	} else {
1639 		if (up->wakeups_enabled) {
1640 			serial_omap_enable_wakeup(up, false);
1641 			up->wakeups_enabled = false;
1642 		}
1643 	}
1644 
1645 	up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1646 	schedule_work(&up->qos_work);
1647 
1648 	return 0;
1649 }
1650 
1651 static int serial_omap_runtime_resume(struct device *dev)
1652 {
1653 	struct uart_omap_port *up = dev_get_drvdata(dev);
1654 
1655 	int loss_cnt = serial_omap_get_context_loss_count(up);
1656 
1657 	if (loss_cnt < 0) {
1658 		dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
1659 			loss_cnt);
1660 		serial_omap_restore_context(up);
1661 	} else if (up->context_loss_cnt != loss_cnt) {
1662 		serial_omap_restore_context(up);
1663 	}
1664 	up->latency = up->calc_latency;
1665 	schedule_work(&up->qos_work);
1666 
1667 	return 0;
1668 }
1669 #endif
1670 
1671 static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1672 	SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1673 	SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1674 				serial_omap_runtime_resume, NULL)
1675 	.prepare        = serial_omap_prepare,
1676 	.complete       = serial_omap_complete,
1677 };
1678 
1679 #if defined(CONFIG_OF)
1680 static const struct of_device_id omap_serial_of_match[] = {
1681 	{ .compatible = "ti,omap2-uart" },
1682 	{ .compatible = "ti,omap3-uart" },
1683 	{ .compatible = "ti,omap4-uart" },
1684 	{},
1685 };
1686 MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1687 #endif
1688 
1689 static struct platform_driver serial_omap_driver = {
1690 	.probe          = serial_omap_probe,
1691 	.remove         = serial_omap_remove,
1692 	.driver		= {
1693 		.name	= DRIVER_NAME,
1694 		.pm	= &serial_omap_dev_pm_ops,
1695 		.of_match_table = of_match_ptr(omap_serial_of_match),
1696 	},
1697 };
1698 
1699 static int __init serial_omap_init(void)
1700 {
1701 	int ret;
1702 
1703 	ret = uart_register_driver(&serial_omap_reg);
1704 	if (ret != 0)
1705 		return ret;
1706 	ret = platform_driver_register(&serial_omap_driver);
1707 	if (ret != 0)
1708 		uart_unregister_driver(&serial_omap_reg);
1709 	return ret;
1710 }
1711 
1712 static void __exit serial_omap_exit(void)
1713 {
1714 	platform_driver_unregister(&serial_omap_driver);
1715 	uart_unregister_driver(&serial_omap_reg);
1716 }
1717 
1718 module_init(serial_omap_init);
1719 module_exit(serial_omap_exit);
1720 
1721 MODULE_DESCRIPTION("OMAP High Speed UART driver");
1722 MODULE_LICENSE("GPL");
1723 MODULE_AUTHOR("Texas Instruments Inc");
1724