xref: /openbmc/linux/drivers/tty/serial/omap-serial.c (revision f3539c12)
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/pm_wakeirq.h>
42 #include <linux/of.h>
43 #include <linux/of_irq.h>
44 #include <linux/gpio.h>
45 #include <linux/of_gpio.h>
46 #include <linux/platform_data/serial-omap.h>
47 
48 #include <dt-bindings/gpio/gpio.h>
49 
50 #define OMAP_MAX_HSUART_PORTS	10
51 
52 #define UART_BUILD_REVISION(x, y)	(((x) << 8) | (y))
53 
54 #define OMAP_UART_REV_42 0x0402
55 #define OMAP_UART_REV_46 0x0406
56 #define OMAP_UART_REV_52 0x0502
57 #define OMAP_UART_REV_63 0x0603
58 
59 #define OMAP_UART_TX_WAKEUP_EN		BIT(7)
60 
61 /* Feature flags */
62 #define OMAP_UART_WER_HAS_TX_WAKEUP	BIT(0)
63 
64 #define UART_ERRATA_i202_MDR1_ACCESS	BIT(0)
65 #define UART_ERRATA_i291_DMA_FORCEIDLE	BIT(1)
66 
67 #define DEFAULT_CLK_SPEED 48000000 /* 48Mhz */
68 
69 /* SCR register bitmasks */
70 #define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK		(1 << 7)
71 #define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK		(1 << 6)
72 #define OMAP_UART_SCR_TX_EMPTY			(1 << 3)
73 
74 /* FCR register bitmasks */
75 #define OMAP_UART_FCR_RX_FIFO_TRIG_MASK			(0x3 << 6)
76 #define OMAP_UART_FCR_TX_FIFO_TRIG_MASK			(0x3 << 4)
77 
78 /* MVR register bitmasks */
79 #define OMAP_UART_MVR_SCHEME_SHIFT	30
80 
81 #define OMAP_UART_LEGACY_MVR_MAJ_MASK	0xf0
82 #define OMAP_UART_LEGACY_MVR_MAJ_SHIFT	4
83 #define OMAP_UART_LEGACY_MVR_MIN_MASK	0x0f
84 
85 #define OMAP_UART_MVR_MAJ_MASK		0x700
86 #define OMAP_UART_MVR_MAJ_SHIFT		8
87 #define OMAP_UART_MVR_MIN_MASK		0x3f
88 
89 #define OMAP_UART_DMA_CH_FREE	-1
90 
91 #define MSR_SAVE_FLAGS		UART_MSR_ANY_DELTA
92 #define OMAP_MODE13X_SPEED	230400
93 
94 /* WER = 0x7F
95  * Enable module level wakeup in WER reg
96  */
97 #define OMAP_UART_WER_MOD_WKUP	0x7F
98 
99 /* Enable XON/XOFF flow control on output */
100 #define OMAP_UART_SW_TX		0x08
101 
102 /* Enable XON/XOFF flow control on input */
103 #define OMAP_UART_SW_RX		0x02
104 
105 #define OMAP_UART_SW_CLR	0xF0
106 
107 #define OMAP_UART_TCR_TRIG	0x0F
108 
109 struct uart_omap_dma {
110 	u8			uart_dma_tx;
111 	u8			uart_dma_rx;
112 	int			rx_dma_channel;
113 	int			tx_dma_channel;
114 	dma_addr_t		rx_buf_dma_phys;
115 	dma_addr_t		tx_buf_dma_phys;
116 	unsigned int		uart_base;
117 	/*
118 	 * Buffer for rx dma. It is not required for tx because the buffer
119 	 * comes from port structure.
120 	 */
121 	unsigned char		*rx_buf;
122 	unsigned int		prev_rx_dma_pos;
123 	int			tx_buf_size;
124 	int			tx_dma_used;
125 	int			rx_dma_used;
126 	spinlock_t		tx_lock;
127 	spinlock_t		rx_lock;
128 	/* timer to poll activity on rx dma */
129 	struct timer_list	rx_timer;
130 	unsigned int		rx_buf_size;
131 	unsigned int		rx_poll_rate;
132 	unsigned int		rx_timeout;
133 };
134 
135 struct uart_omap_port {
136 	struct uart_port	port;
137 	struct uart_omap_dma	uart_dma;
138 	struct device		*dev;
139 	int			wakeirq;
140 
141 	unsigned char		ier;
142 	unsigned char		lcr;
143 	unsigned char		mcr;
144 	unsigned char		fcr;
145 	unsigned char		efr;
146 	unsigned char		dll;
147 	unsigned char		dlh;
148 	unsigned char		mdr1;
149 	unsigned char		scr;
150 	unsigned char		wer;
151 
152 	int			use_dma;
153 	/*
154 	 * Some bits in registers are cleared on a read, so they must
155 	 * be saved whenever the register is read, but the bits will not
156 	 * be immediately processed.
157 	 */
158 	unsigned int		lsr_break_flag;
159 	unsigned char		msr_saved_flags;
160 	char			name[20];
161 	unsigned long		port_activity;
162 	int			context_loss_cnt;
163 	u32			errata;
164 	u32			features;
165 
166 	int			rts_gpio;
167 
168 	struct pm_qos_request	pm_qos_request;
169 	u32			latency;
170 	u32			calc_latency;
171 	struct work_struct	qos_work;
172 	bool			is_suspending;
173 };
174 
175 #define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
176 
177 static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
178 
179 /* Forward declaration of functions */
180 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
181 
182 static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
183 {
184 	offset <<= up->port.regshift;
185 	return readw(up->port.membase + offset);
186 }
187 
188 static inline void serial_out(struct uart_omap_port *up, int offset, int value)
189 {
190 	offset <<= up->port.regshift;
191 	writew(value, up->port.membase + offset);
192 }
193 
194 static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
195 {
196 	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
197 	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
198 		       UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
199 	serial_out(up, UART_FCR, 0);
200 }
201 
202 #ifdef CONFIG_PM
203 static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
204 {
205 	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
206 
207 	if (!pdata || !pdata->get_context_loss_count)
208 		return -EINVAL;
209 
210 	return pdata->get_context_loss_count(up->dev);
211 }
212 
213 /* REVISIT: Remove this when omap3 boots in device tree only mode */
214 static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
215 {
216 	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
217 
218 	if (!pdata || !pdata->enable_wakeup)
219 		return;
220 
221 	pdata->enable_wakeup(up->dev, enable);
222 }
223 #endif /* CONFIG_PM */
224 
225 /*
226  * Calculate the absolute difference between the desired and actual baud
227  * rate for the given mode.
228  */
229 static inline int calculate_baud_abs_diff(struct uart_port *port,
230 				unsigned int baud, unsigned int mode)
231 {
232 	unsigned int n = port->uartclk / (mode * baud);
233 	int abs_diff;
234 
235 	if (n == 0)
236 		n = 1;
237 
238 	abs_diff = baud - (port->uartclk / (mode * n));
239 	if (abs_diff < 0)
240 		abs_diff = -abs_diff;
241 
242 	return abs_diff;
243 }
244 
245 /*
246  * serial_omap_baud_is_mode16 - check if baud rate is MODE16X
247  * @port: uart port info
248  * @baud: baudrate for which mode needs to be determined
249  *
250  * Returns true if baud rate is MODE16X and false if MODE13X
251  * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
252  * and Error Rates" determines modes not for all common baud rates.
253  * E.g. for 1000000 baud rate mode must be 16x, but according to that
254  * table it's determined as 13x.
255  */
256 static bool
257 serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
258 {
259 	int abs_diff_13 = calculate_baud_abs_diff(port, baud, 13);
260 	int abs_diff_16 = calculate_baud_abs_diff(port, baud, 16);
261 
262 	return (abs_diff_13 >= abs_diff_16);
263 }
264 
265 /*
266  * serial_omap_get_divisor - calculate divisor value
267  * @port: uart port info
268  * @baud: baudrate for which divisor needs to be calculated.
269  */
270 static unsigned int
271 serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
272 {
273 	unsigned int mode;
274 
275 	if (!serial_omap_baud_is_mode16(port, baud))
276 		mode = 13;
277 	else
278 		mode = 16;
279 	return port->uartclk/(mode * baud);
280 }
281 
282 static void serial_omap_enable_ms(struct uart_port *port)
283 {
284 	struct uart_omap_port *up = to_uart_omap_port(port);
285 
286 	dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
287 
288 	pm_runtime_get_sync(up->dev);
289 	up->ier |= UART_IER_MSI;
290 	serial_out(up, UART_IER, up->ier);
291 	pm_runtime_mark_last_busy(up->dev);
292 	pm_runtime_put_autosuspend(up->dev);
293 }
294 
295 static void serial_omap_stop_tx(struct uart_port *port)
296 {
297 	struct uart_omap_port *up = to_uart_omap_port(port);
298 	int res;
299 
300 	pm_runtime_get_sync(up->dev);
301 
302 	/* Handle RS-485 */
303 	if (port->rs485.flags & SER_RS485_ENABLED) {
304 		if (up->scr & OMAP_UART_SCR_TX_EMPTY) {
305 			/* THR interrupt is fired when both TX FIFO and TX
306 			 * shift register are empty. This means there's nothing
307 			 * left to transmit now, so make sure the THR interrupt
308 			 * is fired when TX FIFO is below the trigger level,
309 			 * disable THR interrupts and toggle the RS-485 GPIO
310 			 * data direction pin if needed.
311 			 */
312 			up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
313 			serial_out(up, UART_OMAP_SCR, up->scr);
314 			res = (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) ?
315 				1 : 0;
316 			if (gpio_get_value(up->rts_gpio) != res) {
317 				if (port->rs485.delay_rts_after_send > 0)
318 					mdelay(
319 					port->rs485.delay_rts_after_send);
320 				gpio_set_value(up->rts_gpio, res);
321 			}
322 		} else {
323 			/* We're asked to stop, but there's still stuff in the
324 			 * UART FIFO, so make sure the THR interrupt is fired
325 			 * when both TX FIFO and TX shift register are empty.
326 			 * The next THR interrupt (if no transmission is started
327 			 * in the meantime) will indicate the end of a
328 			 * transmission. Therefore we _don't_ disable THR
329 			 * interrupts in this situation.
330 			 */
331 			up->scr |= OMAP_UART_SCR_TX_EMPTY;
332 			serial_out(up, UART_OMAP_SCR, up->scr);
333 			return;
334 		}
335 	}
336 
337 	if (up->ier & UART_IER_THRI) {
338 		up->ier &= ~UART_IER_THRI;
339 		serial_out(up, UART_IER, up->ier);
340 	}
341 
342 	if ((port->rs485.flags & SER_RS485_ENABLED) &&
343 	    !(port->rs485.flags & SER_RS485_RX_DURING_TX)) {
344 		/*
345 		 * Empty the RX FIFO, we are not interested in anything
346 		 * received during the half-duplex transmission.
347 		 */
348 		serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_RCVR);
349 		/* Re-enable RX interrupts */
350 		up->ier |= UART_IER_RLSI | UART_IER_RDI;
351 		up->port.read_status_mask |= UART_LSR_DR;
352 		serial_out(up, UART_IER, up->ier);
353 	}
354 
355 	pm_runtime_mark_last_busy(up->dev);
356 	pm_runtime_put_autosuspend(up->dev);
357 }
358 
359 static void serial_omap_stop_rx(struct uart_port *port)
360 {
361 	struct uart_omap_port *up = to_uart_omap_port(port);
362 
363 	pm_runtime_get_sync(up->dev);
364 	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
365 	up->port.read_status_mask &= ~UART_LSR_DR;
366 	serial_out(up, UART_IER, up->ier);
367 	pm_runtime_mark_last_busy(up->dev);
368 	pm_runtime_put_autosuspend(up->dev);
369 }
370 
371 static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
372 {
373 	struct circ_buf *xmit = &up->port.state->xmit;
374 	int count;
375 
376 	if (up->port.x_char) {
377 		serial_out(up, UART_TX, up->port.x_char);
378 		up->port.icount.tx++;
379 		up->port.x_char = 0;
380 		return;
381 	}
382 	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
383 		serial_omap_stop_tx(&up->port);
384 		return;
385 	}
386 	count = up->port.fifosize / 4;
387 	do {
388 		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
389 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
390 		up->port.icount.tx++;
391 		if (uart_circ_empty(xmit))
392 			break;
393 	} while (--count > 0);
394 
395 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
396 		uart_write_wakeup(&up->port);
397 
398 	if (uart_circ_empty(xmit))
399 		serial_omap_stop_tx(&up->port);
400 }
401 
402 static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
403 {
404 	if (!(up->ier & UART_IER_THRI)) {
405 		up->ier |= UART_IER_THRI;
406 		serial_out(up, UART_IER, up->ier);
407 	}
408 }
409 
410 static void serial_omap_start_tx(struct uart_port *port)
411 {
412 	struct uart_omap_port *up = to_uart_omap_port(port);
413 	int res;
414 
415 	pm_runtime_get_sync(up->dev);
416 
417 	/* Handle RS-485 */
418 	if (port->rs485.flags & SER_RS485_ENABLED) {
419 		/* Fire THR interrupts when FIFO is below trigger level */
420 		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
421 		serial_out(up, UART_OMAP_SCR, up->scr);
422 
423 		/* if rts not already enabled */
424 		res = (port->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
425 		if (gpio_get_value(up->rts_gpio) != res) {
426 			gpio_set_value(up->rts_gpio, res);
427 			if (port->rs485.delay_rts_before_send > 0)
428 				mdelay(port->rs485.delay_rts_before_send);
429 		}
430 	}
431 
432 	if ((port->rs485.flags & SER_RS485_ENABLED) &&
433 	    !(port->rs485.flags & SER_RS485_RX_DURING_TX))
434 		serial_omap_stop_rx(port);
435 
436 	serial_omap_enable_ier_thri(up);
437 	pm_runtime_mark_last_busy(up->dev);
438 	pm_runtime_put_autosuspend(up->dev);
439 }
440 
441 static void serial_omap_throttle(struct uart_port *port)
442 {
443 	struct uart_omap_port *up = to_uart_omap_port(port);
444 	unsigned long flags;
445 
446 	pm_runtime_get_sync(up->dev);
447 	spin_lock_irqsave(&up->port.lock, flags);
448 	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
449 	serial_out(up, UART_IER, up->ier);
450 	spin_unlock_irqrestore(&up->port.lock, flags);
451 	pm_runtime_mark_last_busy(up->dev);
452 	pm_runtime_put_autosuspend(up->dev);
453 }
454 
455 static void serial_omap_unthrottle(struct uart_port *port)
456 {
457 	struct uart_omap_port *up = to_uart_omap_port(port);
458 	unsigned long flags;
459 
460 	pm_runtime_get_sync(up->dev);
461 	spin_lock_irqsave(&up->port.lock, flags);
462 	up->ier |= UART_IER_RLSI | UART_IER_RDI;
463 	serial_out(up, UART_IER, up->ier);
464 	spin_unlock_irqrestore(&up->port.lock, flags);
465 	pm_runtime_mark_last_busy(up->dev);
466 	pm_runtime_put_autosuspend(up->dev);
467 }
468 
469 static unsigned int check_modem_status(struct uart_omap_port *up)
470 {
471 	unsigned int status;
472 
473 	status = serial_in(up, UART_MSR);
474 	status |= up->msr_saved_flags;
475 	up->msr_saved_flags = 0;
476 	if ((status & UART_MSR_ANY_DELTA) == 0)
477 		return status;
478 
479 	if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
480 	    up->port.state != NULL) {
481 		if (status & UART_MSR_TERI)
482 			up->port.icount.rng++;
483 		if (status & UART_MSR_DDSR)
484 			up->port.icount.dsr++;
485 		if (status & UART_MSR_DDCD)
486 			uart_handle_dcd_change
487 				(&up->port, status & UART_MSR_DCD);
488 		if (status & UART_MSR_DCTS)
489 			uart_handle_cts_change
490 				(&up->port, status & UART_MSR_CTS);
491 		wake_up_interruptible(&up->port.state->port.delta_msr_wait);
492 	}
493 
494 	return status;
495 }
496 
497 static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
498 {
499 	unsigned int flag;
500 	unsigned char ch = 0;
501 
502 	if (likely(lsr & UART_LSR_DR))
503 		ch = serial_in(up, UART_RX);
504 
505 	up->port.icount.rx++;
506 	flag = TTY_NORMAL;
507 
508 	if (lsr & UART_LSR_BI) {
509 		flag = TTY_BREAK;
510 		lsr &= ~(UART_LSR_FE | UART_LSR_PE);
511 		up->port.icount.brk++;
512 		/*
513 		 * We do the SysRQ and SAK checking
514 		 * here because otherwise the break
515 		 * may get masked by ignore_status_mask
516 		 * or read_status_mask.
517 		 */
518 		if (uart_handle_break(&up->port))
519 			return;
520 
521 	}
522 
523 	if (lsr & UART_LSR_PE) {
524 		flag = TTY_PARITY;
525 		up->port.icount.parity++;
526 	}
527 
528 	if (lsr & UART_LSR_FE) {
529 		flag = TTY_FRAME;
530 		up->port.icount.frame++;
531 	}
532 
533 	if (lsr & UART_LSR_OE)
534 		up->port.icount.overrun++;
535 
536 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
537 	if (up->port.line == up->port.cons->index) {
538 		/* Recover the break flag from console xmit */
539 		lsr |= up->lsr_break_flag;
540 	}
541 #endif
542 	uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag);
543 }
544 
545 static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
546 {
547 	unsigned char ch = 0;
548 	unsigned int flag;
549 
550 	if (!(lsr & UART_LSR_DR))
551 		return;
552 
553 	ch = serial_in(up, UART_RX);
554 	flag = TTY_NORMAL;
555 	up->port.icount.rx++;
556 
557 	if (uart_handle_sysrq_char(&up->port, ch))
558 		return;
559 
560 	uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
561 }
562 
563 /**
564  * serial_omap_irq() - This handles the interrupt from one port
565  * @irq: uart port irq number
566  * @dev_id: uart port info
567  */
568 static irqreturn_t serial_omap_irq(int irq, void *dev_id)
569 {
570 	struct uart_omap_port *up = dev_id;
571 	unsigned int iir, lsr;
572 	unsigned int type;
573 	irqreturn_t ret = IRQ_NONE;
574 	int max_count = 256;
575 
576 	spin_lock(&up->port.lock);
577 	pm_runtime_get_sync(up->dev);
578 
579 	do {
580 		iir = serial_in(up, UART_IIR);
581 		if (iir & UART_IIR_NO_INT)
582 			break;
583 
584 		ret = IRQ_HANDLED;
585 		lsr = serial_in(up, UART_LSR);
586 
587 		/* extract IRQ type from IIR register */
588 		type = iir & 0x3e;
589 
590 		switch (type) {
591 		case UART_IIR_MSI:
592 			check_modem_status(up);
593 			break;
594 		case UART_IIR_THRI:
595 			transmit_chars(up, lsr);
596 			break;
597 		case UART_IIR_RX_TIMEOUT:
598 			/* FALLTHROUGH */
599 		case UART_IIR_RDI:
600 			serial_omap_rdi(up, lsr);
601 			break;
602 		case UART_IIR_RLSI:
603 			serial_omap_rlsi(up, lsr);
604 			break;
605 		case UART_IIR_CTS_RTS_DSR:
606 			/* simply try again */
607 			break;
608 		case UART_IIR_XOFF:
609 			/* FALLTHROUGH */
610 		default:
611 			break;
612 		}
613 	} while (!(iir & UART_IIR_NO_INT) && max_count--);
614 
615 	spin_unlock(&up->port.lock);
616 
617 	tty_flip_buffer_push(&up->port.state->port);
618 
619 	pm_runtime_mark_last_busy(up->dev);
620 	pm_runtime_put_autosuspend(up->dev);
621 	up->port_activity = jiffies;
622 
623 	return ret;
624 }
625 
626 static unsigned int serial_omap_tx_empty(struct uart_port *port)
627 {
628 	struct uart_omap_port *up = to_uart_omap_port(port);
629 	unsigned long flags = 0;
630 	unsigned int ret = 0;
631 
632 	pm_runtime_get_sync(up->dev);
633 	dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
634 	spin_lock_irqsave(&up->port.lock, flags);
635 	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
636 	spin_unlock_irqrestore(&up->port.lock, flags);
637 	pm_runtime_mark_last_busy(up->dev);
638 	pm_runtime_put_autosuspend(up->dev);
639 	return ret;
640 }
641 
642 static unsigned int serial_omap_get_mctrl(struct uart_port *port)
643 {
644 	struct uart_omap_port *up = to_uart_omap_port(port);
645 	unsigned int status;
646 	unsigned int ret = 0;
647 
648 	pm_runtime_get_sync(up->dev);
649 	status = check_modem_status(up);
650 	pm_runtime_mark_last_busy(up->dev);
651 	pm_runtime_put_autosuspend(up->dev);
652 
653 	dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
654 
655 	if (status & UART_MSR_DCD)
656 		ret |= TIOCM_CAR;
657 	if (status & UART_MSR_RI)
658 		ret |= TIOCM_RNG;
659 	if (status & UART_MSR_DSR)
660 		ret |= TIOCM_DSR;
661 	if (status & UART_MSR_CTS)
662 		ret |= TIOCM_CTS;
663 	return ret;
664 }
665 
666 static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
667 {
668 	struct uart_omap_port *up = to_uart_omap_port(port);
669 	unsigned char mcr = 0, old_mcr, lcr;
670 
671 	dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
672 	if (mctrl & TIOCM_RTS)
673 		mcr |= UART_MCR_RTS;
674 	if (mctrl & TIOCM_DTR)
675 		mcr |= UART_MCR_DTR;
676 	if (mctrl & TIOCM_OUT1)
677 		mcr |= UART_MCR_OUT1;
678 	if (mctrl & TIOCM_OUT2)
679 		mcr |= UART_MCR_OUT2;
680 	if (mctrl & TIOCM_LOOP)
681 		mcr |= UART_MCR_LOOP;
682 
683 	pm_runtime_get_sync(up->dev);
684 	old_mcr = serial_in(up, UART_MCR);
685 	old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
686 		     UART_MCR_DTR | UART_MCR_RTS);
687 	up->mcr = old_mcr | mcr;
688 	serial_out(up, UART_MCR, up->mcr);
689 
690 	/* Turn off autoRTS if RTS is lowered; restore autoRTS if RTS raised */
691 	lcr = serial_in(up, UART_LCR);
692 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
693 	if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS))
694 		up->efr |= UART_EFR_RTS;
695 	else
696 		up->efr &= UART_EFR_RTS;
697 	serial_out(up, UART_EFR, up->efr);
698 	serial_out(up, UART_LCR, lcr);
699 
700 	pm_runtime_mark_last_busy(up->dev);
701 	pm_runtime_put_autosuspend(up->dev);
702 }
703 
704 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
705 {
706 	struct uart_omap_port *up = to_uart_omap_port(port);
707 	unsigned long flags = 0;
708 
709 	dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
710 	pm_runtime_get_sync(up->dev);
711 	spin_lock_irqsave(&up->port.lock, flags);
712 	if (break_state == -1)
713 		up->lcr |= UART_LCR_SBC;
714 	else
715 		up->lcr &= ~UART_LCR_SBC;
716 	serial_out(up, UART_LCR, up->lcr);
717 	spin_unlock_irqrestore(&up->port.lock, flags);
718 	pm_runtime_mark_last_busy(up->dev);
719 	pm_runtime_put_autosuspend(up->dev);
720 }
721 
722 static int serial_omap_startup(struct uart_port *port)
723 {
724 	struct uart_omap_port *up = to_uart_omap_port(port);
725 	unsigned long flags = 0;
726 	int retval;
727 
728 	/*
729 	 * Allocate the IRQ
730 	 */
731 	retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
732 				up->name, up);
733 	if (retval)
734 		return retval;
735 
736 	/* Optional wake-up IRQ */
737 	if (up->wakeirq) {
738 		retval = dev_pm_set_dedicated_wake_irq(up->dev, up->wakeirq);
739 		if (retval) {
740 			free_irq(up->port.irq, up);
741 			return retval;
742 		}
743 	}
744 
745 	dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
746 
747 	pm_runtime_get_sync(up->dev);
748 	/*
749 	 * Clear the FIFO buffers and disable them.
750 	 * (they will be reenabled in set_termios())
751 	 */
752 	serial_omap_clear_fifos(up);
753 
754 	/*
755 	 * Clear the interrupt registers.
756 	 */
757 	(void) serial_in(up, UART_LSR);
758 	if (serial_in(up, UART_LSR) & UART_LSR_DR)
759 		(void) serial_in(up, UART_RX);
760 	(void) serial_in(up, UART_IIR);
761 	(void) serial_in(up, UART_MSR);
762 
763 	/*
764 	 * Now, initialize the UART
765 	 */
766 	serial_out(up, UART_LCR, UART_LCR_WLEN8);
767 	spin_lock_irqsave(&up->port.lock, flags);
768 	/*
769 	 * Most PC uarts need OUT2 raised to enable interrupts.
770 	 */
771 	up->port.mctrl |= TIOCM_OUT2;
772 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
773 	spin_unlock_irqrestore(&up->port.lock, flags);
774 
775 	up->msr_saved_flags = 0;
776 	/*
777 	 * Finally, enable interrupts. Note: Modem status interrupts
778 	 * are set via set_termios(), which will be occurring imminently
779 	 * anyway, so we don't enable them here.
780 	 */
781 	up->ier = UART_IER_RLSI | UART_IER_RDI;
782 	serial_out(up, UART_IER, up->ier);
783 
784 	/* Enable module level wake up */
785 	up->wer = OMAP_UART_WER_MOD_WKUP;
786 	if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
787 		up->wer |= OMAP_UART_TX_WAKEUP_EN;
788 
789 	serial_out(up, UART_OMAP_WER, up->wer);
790 
791 	pm_runtime_mark_last_busy(up->dev);
792 	pm_runtime_put_autosuspend(up->dev);
793 	up->port_activity = jiffies;
794 	return 0;
795 }
796 
797 static void serial_omap_shutdown(struct uart_port *port)
798 {
799 	struct uart_omap_port *up = to_uart_omap_port(port);
800 	unsigned long flags = 0;
801 
802 	dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
803 
804 	pm_runtime_get_sync(up->dev);
805 	/*
806 	 * Disable interrupts from this port
807 	 */
808 	up->ier = 0;
809 	serial_out(up, UART_IER, 0);
810 
811 	spin_lock_irqsave(&up->port.lock, flags);
812 	up->port.mctrl &= ~TIOCM_OUT2;
813 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
814 	spin_unlock_irqrestore(&up->port.lock, flags);
815 
816 	/*
817 	 * Disable break condition and FIFOs
818 	 */
819 	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
820 	serial_omap_clear_fifos(up);
821 
822 	/*
823 	 * Read data port to reset things, and then free the irq
824 	 */
825 	if (serial_in(up, UART_LSR) & UART_LSR_DR)
826 		(void) serial_in(up, UART_RX);
827 
828 	pm_runtime_mark_last_busy(up->dev);
829 	pm_runtime_put_autosuspend(up->dev);
830 	free_irq(up->port.irq, up);
831 	dev_pm_clear_wake_irq(up->dev);
832 }
833 
834 static void serial_omap_uart_qos_work(struct work_struct *work)
835 {
836 	struct uart_omap_port *up = container_of(work, struct uart_omap_port,
837 						qos_work);
838 
839 	pm_qos_update_request(&up->pm_qos_request, up->latency);
840 }
841 
842 static void
843 serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
844 			struct ktermios *old)
845 {
846 	struct uart_omap_port *up = to_uart_omap_port(port);
847 	unsigned char cval = 0;
848 	unsigned long flags = 0;
849 	unsigned int baud, quot;
850 
851 	switch (termios->c_cflag & CSIZE) {
852 	case CS5:
853 		cval = UART_LCR_WLEN5;
854 		break;
855 	case CS6:
856 		cval = UART_LCR_WLEN6;
857 		break;
858 	case CS7:
859 		cval = UART_LCR_WLEN7;
860 		break;
861 	default:
862 	case CS8:
863 		cval = UART_LCR_WLEN8;
864 		break;
865 	}
866 
867 	if (termios->c_cflag & CSTOPB)
868 		cval |= UART_LCR_STOP;
869 	if (termios->c_cflag & PARENB)
870 		cval |= UART_LCR_PARITY;
871 	if (!(termios->c_cflag & PARODD))
872 		cval |= UART_LCR_EPAR;
873 	if (termios->c_cflag & CMSPAR)
874 		cval |= UART_LCR_SPAR;
875 
876 	/*
877 	 * Ask the core to calculate the divisor for us.
878 	 */
879 
880 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
881 	quot = serial_omap_get_divisor(port, baud);
882 
883 	/* calculate wakeup latency constraint */
884 	up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
885 	up->latency = up->calc_latency;
886 	schedule_work(&up->qos_work);
887 
888 	up->dll = quot & 0xff;
889 	up->dlh = quot >> 8;
890 	up->mdr1 = UART_OMAP_MDR1_DISABLE;
891 
892 	up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
893 			UART_FCR_ENABLE_FIFO;
894 
895 	/*
896 	 * Ok, we're now changing the port state. Do it with
897 	 * interrupts disabled.
898 	 */
899 	pm_runtime_get_sync(up->dev);
900 	spin_lock_irqsave(&up->port.lock, flags);
901 
902 	/*
903 	 * Update the per-port timeout.
904 	 */
905 	uart_update_timeout(port, termios->c_cflag, baud);
906 
907 	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
908 	if (termios->c_iflag & INPCK)
909 		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
910 	if (termios->c_iflag & (BRKINT | PARMRK))
911 		up->port.read_status_mask |= UART_LSR_BI;
912 
913 	/*
914 	 * Characters to ignore
915 	 */
916 	up->port.ignore_status_mask = 0;
917 	if (termios->c_iflag & IGNPAR)
918 		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
919 	if (termios->c_iflag & IGNBRK) {
920 		up->port.ignore_status_mask |= UART_LSR_BI;
921 		/*
922 		 * If we're ignoring parity and break indicators,
923 		 * ignore overruns too (for real raw support).
924 		 */
925 		if (termios->c_iflag & IGNPAR)
926 			up->port.ignore_status_mask |= UART_LSR_OE;
927 	}
928 
929 	/*
930 	 * ignore all characters if CREAD is not set
931 	 */
932 	if ((termios->c_cflag & CREAD) == 0)
933 		up->port.ignore_status_mask |= UART_LSR_DR;
934 
935 	/*
936 	 * Modem status interrupts
937 	 */
938 	up->ier &= ~UART_IER_MSI;
939 	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
940 		up->ier |= UART_IER_MSI;
941 	serial_out(up, UART_IER, up->ier);
942 	serial_out(up, UART_LCR, cval);		/* reset DLAB */
943 	up->lcr = cval;
944 	up->scr = 0;
945 
946 	/* FIFOs and DMA Settings */
947 
948 	/* FCR can be changed only when the
949 	 * baud clock is not running
950 	 * DLL_REG and DLH_REG set to 0.
951 	 */
952 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
953 	serial_out(up, UART_DLL, 0);
954 	serial_out(up, UART_DLM, 0);
955 	serial_out(up, UART_LCR, 0);
956 
957 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
958 
959 	up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
960 	up->efr &= ~UART_EFR_SCD;
961 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
962 
963 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
964 	up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
965 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
966 	/* FIFO ENABLE, DMA MODE */
967 
968 	up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
969 	/*
970 	 * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
971 	 * sets Enables the granularity of 1 for TRIGGER RX
972 	 * level. Along with setting RX FIFO trigger level
973 	 * to 1 (as noted below, 16 characters) and TLR[3:0]
974 	 * to zero this will result RX FIFO threshold level
975 	 * to 1 character, instead of 16 as noted in comment
976 	 * below.
977 	 */
978 
979 	/* Set receive FIFO threshold to 16 characters and
980 	 * transmit FIFO threshold to 32 spaces
981 	 */
982 	up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
983 	up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
984 	up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
985 		UART_FCR_ENABLE_FIFO;
986 
987 	serial_out(up, UART_FCR, up->fcr);
988 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
989 
990 	serial_out(up, UART_OMAP_SCR, up->scr);
991 
992 	/* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
993 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
994 	serial_out(up, UART_MCR, up->mcr);
995 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
996 	serial_out(up, UART_EFR, up->efr);
997 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
998 
999 	/* Protocol, Baud Rate, and Interrupt Settings */
1000 
1001 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1002 		serial_omap_mdr1_errataset(up, up->mdr1);
1003 	else
1004 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1005 
1006 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1007 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1008 
1009 	serial_out(up, UART_LCR, 0);
1010 	serial_out(up, UART_IER, 0);
1011 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1012 
1013 	serial_out(up, UART_DLL, up->dll);	/* LS of divisor */
1014 	serial_out(up, UART_DLM, up->dlh);	/* MS of divisor */
1015 
1016 	serial_out(up, UART_LCR, 0);
1017 	serial_out(up, UART_IER, up->ier);
1018 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1019 
1020 	serial_out(up, UART_EFR, up->efr);
1021 	serial_out(up, UART_LCR, cval);
1022 
1023 	if (!serial_omap_baud_is_mode16(port, baud))
1024 		up->mdr1 = UART_OMAP_MDR1_13X_MODE;
1025 	else
1026 		up->mdr1 = UART_OMAP_MDR1_16X_MODE;
1027 
1028 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1029 		serial_omap_mdr1_errataset(up, up->mdr1);
1030 	else
1031 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1032 
1033 	/* Configure flow control */
1034 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1035 
1036 	/* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
1037 	serial_out(up, UART_XON1, termios->c_cc[VSTART]);
1038 	serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
1039 
1040 	/* Enable access to TCR/TLR */
1041 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1042 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1043 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
1044 
1045 	serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
1046 
1047 	up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
1048 
1049 	if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
1050 		/* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */
1051 		up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
1052 		up->efr |= UART_EFR_CTS;
1053 	} else {
1054 		/* Disable AUTORTS and AUTOCTS */
1055 		up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
1056 	}
1057 
1058 	if (up->port.flags & UPF_SOFT_FLOW) {
1059 		/* clear SW control mode bits */
1060 		up->efr &= OMAP_UART_SW_CLR;
1061 
1062 		/*
1063 		 * IXON Flag:
1064 		 * Enable XON/XOFF flow control on input.
1065 		 * Receiver compares XON1, XOFF1.
1066 		 */
1067 		if (termios->c_iflag & IXON)
1068 			up->efr |= OMAP_UART_SW_RX;
1069 
1070 		/*
1071 		 * IXOFF Flag:
1072 		 * Enable XON/XOFF flow control on output.
1073 		 * Transmit XON1, XOFF1
1074 		 */
1075 		if (termios->c_iflag & IXOFF) {
1076 			up->port.status |= UPSTAT_AUTOXOFF;
1077 			up->efr |= OMAP_UART_SW_TX;
1078 		}
1079 
1080 		/*
1081 		 * IXANY Flag:
1082 		 * Enable any character to restart output.
1083 		 * Operation resumes after receiving any
1084 		 * character after recognition of the XOFF character
1085 		 */
1086 		if (termios->c_iflag & IXANY)
1087 			up->mcr |= UART_MCR_XONANY;
1088 		else
1089 			up->mcr &= ~UART_MCR_XONANY;
1090 	}
1091 	serial_out(up, UART_MCR, up->mcr);
1092 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1093 	serial_out(up, UART_EFR, up->efr);
1094 	serial_out(up, UART_LCR, up->lcr);
1095 
1096 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
1097 
1098 	spin_unlock_irqrestore(&up->port.lock, flags);
1099 	pm_runtime_mark_last_busy(up->dev);
1100 	pm_runtime_put_autosuspend(up->dev);
1101 	dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
1102 }
1103 
1104 static void
1105 serial_omap_pm(struct uart_port *port, unsigned int state,
1106 	       unsigned int oldstate)
1107 {
1108 	struct uart_omap_port *up = to_uart_omap_port(port);
1109 	unsigned char efr;
1110 
1111 	dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
1112 
1113 	pm_runtime_get_sync(up->dev);
1114 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1115 	efr = serial_in(up, UART_EFR);
1116 	serial_out(up, UART_EFR, efr | UART_EFR_ECB);
1117 	serial_out(up, UART_LCR, 0);
1118 
1119 	serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
1120 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1121 	serial_out(up, UART_EFR, efr);
1122 	serial_out(up, UART_LCR, 0);
1123 
1124 	pm_runtime_mark_last_busy(up->dev);
1125 	pm_runtime_put_autosuspend(up->dev);
1126 }
1127 
1128 static void serial_omap_release_port(struct uart_port *port)
1129 {
1130 	dev_dbg(port->dev, "serial_omap_release_port+\n");
1131 }
1132 
1133 static int serial_omap_request_port(struct uart_port *port)
1134 {
1135 	dev_dbg(port->dev, "serial_omap_request_port+\n");
1136 	return 0;
1137 }
1138 
1139 static void serial_omap_config_port(struct uart_port *port, int flags)
1140 {
1141 	struct uart_omap_port *up = to_uart_omap_port(port);
1142 
1143 	dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
1144 							up->port.line);
1145 	up->port.type = PORT_OMAP;
1146 	up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
1147 }
1148 
1149 static int
1150 serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
1151 {
1152 	/* we don't want the core code to modify any port params */
1153 	dev_dbg(port->dev, "serial_omap_verify_port+\n");
1154 	return -EINVAL;
1155 }
1156 
1157 static const char *
1158 serial_omap_type(struct uart_port *port)
1159 {
1160 	struct uart_omap_port *up = to_uart_omap_port(port);
1161 
1162 	dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
1163 	return up->name;
1164 }
1165 
1166 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1167 
1168 static void __maybe_unused wait_for_xmitr(struct uart_omap_port *up)
1169 {
1170 	unsigned int status, tmout = 10000;
1171 
1172 	/* Wait up to 10ms for the character(s) to be sent. */
1173 	do {
1174 		status = serial_in(up, UART_LSR);
1175 
1176 		if (status & UART_LSR_BI)
1177 			up->lsr_break_flag = UART_LSR_BI;
1178 
1179 		if (--tmout == 0)
1180 			break;
1181 		udelay(1);
1182 	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
1183 
1184 	/* Wait up to 1s for flow control if necessary */
1185 	if (up->port.flags & UPF_CONS_FLOW) {
1186 		tmout = 1000000;
1187 		for (tmout = 1000000; tmout; tmout--) {
1188 			unsigned int msr = serial_in(up, UART_MSR);
1189 
1190 			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1191 			if (msr & UART_MSR_CTS)
1192 				break;
1193 
1194 			udelay(1);
1195 		}
1196 	}
1197 }
1198 
1199 #ifdef CONFIG_CONSOLE_POLL
1200 
1201 static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
1202 {
1203 	struct uart_omap_port *up = to_uart_omap_port(port);
1204 
1205 	pm_runtime_get_sync(up->dev);
1206 	wait_for_xmitr(up);
1207 	serial_out(up, UART_TX, ch);
1208 	pm_runtime_mark_last_busy(up->dev);
1209 	pm_runtime_put_autosuspend(up->dev);
1210 }
1211 
1212 static int serial_omap_poll_get_char(struct uart_port *port)
1213 {
1214 	struct uart_omap_port *up = to_uart_omap_port(port);
1215 	unsigned int status;
1216 
1217 	pm_runtime_get_sync(up->dev);
1218 	status = serial_in(up, UART_LSR);
1219 	if (!(status & UART_LSR_DR)) {
1220 		status = NO_POLL_CHAR;
1221 		goto out;
1222 	}
1223 
1224 	status = serial_in(up, UART_RX);
1225 
1226 out:
1227 	pm_runtime_mark_last_busy(up->dev);
1228 	pm_runtime_put_autosuspend(up->dev);
1229 
1230 	return status;
1231 }
1232 
1233 #endif /* CONFIG_CONSOLE_POLL */
1234 
1235 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
1236 
1237 static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
1238 
1239 static struct uart_driver serial_omap_reg;
1240 
1241 static void serial_omap_console_putchar(struct uart_port *port, int ch)
1242 {
1243 	struct uart_omap_port *up = to_uart_omap_port(port);
1244 
1245 	wait_for_xmitr(up);
1246 	serial_out(up, UART_TX, ch);
1247 }
1248 
1249 static void
1250 serial_omap_console_write(struct console *co, const char *s,
1251 		unsigned int count)
1252 {
1253 	struct uart_omap_port *up = serial_omap_console_ports[co->index];
1254 	unsigned long flags;
1255 	unsigned int ier;
1256 	int locked = 1;
1257 
1258 	pm_runtime_get_sync(up->dev);
1259 
1260 	local_irq_save(flags);
1261 	if (up->port.sysrq)
1262 		locked = 0;
1263 	else if (oops_in_progress)
1264 		locked = spin_trylock(&up->port.lock);
1265 	else
1266 		spin_lock(&up->port.lock);
1267 
1268 	/*
1269 	 * First save the IER then disable the interrupts
1270 	 */
1271 	ier = serial_in(up, UART_IER);
1272 	serial_out(up, UART_IER, 0);
1273 
1274 	uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1275 
1276 	/*
1277 	 * Finally, wait for transmitter to become empty
1278 	 * and restore the IER
1279 	 */
1280 	wait_for_xmitr(up);
1281 	serial_out(up, UART_IER, ier);
1282 	/*
1283 	 * The receive handling will happen properly because the
1284 	 * receive ready bit will still be set; it is not cleared
1285 	 * on read.  However, modem control will not, we must
1286 	 * call it if we have saved something in the saved flags
1287 	 * while processing with interrupts off.
1288 	 */
1289 	if (up->msr_saved_flags)
1290 		check_modem_status(up);
1291 
1292 	pm_runtime_mark_last_busy(up->dev);
1293 	pm_runtime_put_autosuspend(up->dev);
1294 	if (locked)
1295 		spin_unlock(&up->port.lock);
1296 	local_irq_restore(flags);
1297 }
1298 
1299 static int __init
1300 serial_omap_console_setup(struct console *co, char *options)
1301 {
1302 	struct uart_omap_port *up;
1303 	int baud = 115200;
1304 	int bits = 8;
1305 	int parity = 'n';
1306 	int flow = 'n';
1307 
1308 	if (serial_omap_console_ports[co->index] == NULL)
1309 		return -ENODEV;
1310 	up = serial_omap_console_ports[co->index];
1311 
1312 	if (options)
1313 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1314 
1315 	return uart_set_options(&up->port, co, baud, parity, bits, flow);
1316 }
1317 
1318 static struct console serial_omap_console = {
1319 	.name		= OMAP_SERIAL_NAME,
1320 	.write		= serial_omap_console_write,
1321 	.device		= uart_console_device,
1322 	.setup		= serial_omap_console_setup,
1323 	.flags		= CON_PRINTBUFFER,
1324 	.index		= -1,
1325 	.data		= &serial_omap_reg,
1326 };
1327 
1328 static void serial_omap_add_console_port(struct uart_omap_port *up)
1329 {
1330 	serial_omap_console_ports[up->port.line] = up;
1331 }
1332 
1333 #define OMAP_CONSOLE	(&serial_omap_console)
1334 
1335 #else
1336 
1337 #define OMAP_CONSOLE	NULL
1338 
1339 static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1340 {}
1341 
1342 #endif
1343 
1344 /* Enable or disable the rs485 support */
1345 static int
1346 serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485)
1347 {
1348 	struct uart_omap_port *up = to_uart_omap_port(port);
1349 	unsigned int mode;
1350 	int val;
1351 
1352 	pm_runtime_get_sync(up->dev);
1353 
1354 	/* Disable interrupts from this port */
1355 	mode = up->ier;
1356 	up->ier = 0;
1357 	serial_out(up, UART_IER, 0);
1358 
1359 	/* Clamp the delays to [0, 100ms] */
1360 	rs485->delay_rts_before_send = min(rs485->delay_rts_before_send, 100U);
1361 	rs485->delay_rts_after_send  = min(rs485->delay_rts_after_send, 100U);
1362 
1363 	/* store new config */
1364 	port->rs485 = *rs485;
1365 
1366 	/*
1367 	 * Just as a precaution, only allow rs485
1368 	 * to be enabled if the gpio pin is valid
1369 	 */
1370 	if (gpio_is_valid(up->rts_gpio)) {
1371 		/* enable / disable rts */
1372 		val = (port->rs485.flags & SER_RS485_ENABLED) ?
1373 			SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
1374 		val = (port->rs485.flags & val) ? 1 : 0;
1375 		gpio_set_value(up->rts_gpio, val);
1376 	} else
1377 		port->rs485.flags &= ~SER_RS485_ENABLED;
1378 
1379 	/* Enable interrupts */
1380 	up->ier = mode;
1381 	serial_out(up, UART_IER, up->ier);
1382 
1383 	/* If RS-485 is disabled, make sure the THR interrupt is fired when
1384 	 * TX FIFO is below the trigger level.
1385 	 */
1386 	if (!(port->rs485.flags & SER_RS485_ENABLED) &&
1387 	    (up->scr & OMAP_UART_SCR_TX_EMPTY)) {
1388 		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
1389 		serial_out(up, UART_OMAP_SCR, up->scr);
1390 	}
1391 
1392 	pm_runtime_mark_last_busy(up->dev);
1393 	pm_runtime_put_autosuspend(up->dev);
1394 
1395 	return 0;
1396 }
1397 
1398 static struct uart_ops serial_omap_pops = {
1399 	.tx_empty	= serial_omap_tx_empty,
1400 	.set_mctrl	= serial_omap_set_mctrl,
1401 	.get_mctrl	= serial_omap_get_mctrl,
1402 	.stop_tx	= serial_omap_stop_tx,
1403 	.start_tx	= serial_omap_start_tx,
1404 	.throttle	= serial_omap_throttle,
1405 	.unthrottle	= serial_omap_unthrottle,
1406 	.stop_rx	= serial_omap_stop_rx,
1407 	.enable_ms	= serial_omap_enable_ms,
1408 	.break_ctl	= serial_omap_break_ctl,
1409 	.startup	= serial_omap_startup,
1410 	.shutdown	= serial_omap_shutdown,
1411 	.set_termios	= serial_omap_set_termios,
1412 	.pm		= serial_omap_pm,
1413 	.type		= serial_omap_type,
1414 	.release_port	= serial_omap_release_port,
1415 	.request_port	= serial_omap_request_port,
1416 	.config_port	= serial_omap_config_port,
1417 	.verify_port	= serial_omap_verify_port,
1418 #ifdef CONFIG_CONSOLE_POLL
1419 	.poll_put_char  = serial_omap_poll_put_char,
1420 	.poll_get_char  = serial_omap_poll_get_char,
1421 #endif
1422 };
1423 
1424 static struct uart_driver serial_omap_reg = {
1425 	.owner		= THIS_MODULE,
1426 	.driver_name	= "OMAP-SERIAL",
1427 	.dev_name	= OMAP_SERIAL_NAME,
1428 	.nr		= OMAP_MAX_HSUART_PORTS,
1429 	.cons		= OMAP_CONSOLE,
1430 };
1431 
1432 #ifdef CONFIG_PM_SLEEP
1433 static int serial_omap_prepare(struct device *dev)
1434 {
1435 	struct uart_omap_port *up = dev_get_drvdata(dev);
1436 
1437 	up->is_suspending = true;
1438 
1439 	return 0;
1440 }
1441 
1442 static void serial_omap_complete(struct device *dev)
1443 {
1444 	struct uart_omap_port *up = dev_get_drvdata(dev);
1445 
1446 	up->is_suspending = false;
1447 }
1448 
1449 static int serial_omap_suspend(struct device *dev)
1450 {
1451 	struct uart_omap_port *up = dev_get_drvdata(dev);
1452 
1453 	uart_suspend_port(&serial_omap_reg, &up->port);
1454 	flush_work(&up->qos_work);
1455 
1456 	if (device_may_wakeup(dev))
1457 		serial_omap_enable_wakeup(up, true);
1458 	else
1459 		serial_omap_enable_wakeup(up, false);
1460 
1461 	return 0;
1462 }
1463 
1464 static int serial_omap_resume(struct device *dev)
1465 {
1466 	struct uart_omap_port *up = dev_get_drvdata(dev);
1467 
1468 	if (device_may_wakeup(dev))
1469 		serial_omap_enable_wakeup(up, false);
1470 
1471 	uart_resume_port(&serial_omap_reg, &up->port);
1472 
1473 	return 0;
1474 }
1475 #else
1476 #define serial_omap_prepare NULL
1477 #define serial_omap_complete NULL
1478 #endif /* CONFIG_PM_SLEEP */
1479 
1480 static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
1481 {
1482 	u32 mvr, scheme;
1483 	u16 revision, major, minor;
1484 
1485 	mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
1486 
1487 	/* Check revision register scheme */
1488 	scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
1489 
1490 	switch (scheme) {
1491 	case 0: /* Legacy Scheme: OMAP2/3 */
1492 		/* MINOR_REV[0:4], MAJOR_REV[4:7] */
1493 		major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
1494 					OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
1495 		minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
1496 		break;
1497 	case 1:
1498 		/* New Scheme: OMAP4+ */
1499 		/* MINOR_REV[0:5], MAJOR_REV[8:10] */
1500 		major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
1501 					OMAP_UART_MVR_MAJ_SHIFT;
1502 		minor = (mvr & OMAP_UART_MVR_MIN_MASK);
1503 		break;
1504 	default:
1505 		dev_warn(up->dev,
1506 			"Unknown %s revision, defaulting to highest\n",
1507 			up->name);
1508 		/* highest possible revision */
1509 		major = 0xff;
1510 		minor = 0xff;
1511 	}
1512 
1513 	/* normalize revision for the driver */
1514 	revision = UART_BUILD_REVISION(major, minor);
1515 
1516 	switch (revision) {
1517 	case OMAP_UART_REV_46:
1518 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1519 				UART_ERRATA_i291_DMA_FORCEIDLE);
1520 		break;
1521 	case OMAP_UART_REV_52:
1522 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1523 				UART_ERRATA_i291_DMA_FORCEIDLE);
1524 		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1525 		break;
1526 	case OMAP_UART_REV_63:
1527 		up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
1528 		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1529 		break;
1530 	default:
1531 		break;
1532 	}
1533 }
1534 
1535 static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1536 {
1537 	struct omap_uart_port_info *omap_up_info;
1538 
1539 	omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1540 	if (!omap_up_info)
1541 		return NULL; /* out of memory */
1542 
1543 	of_property_read_u32(dev->of_node, "clock-frequency",
1544 					 &omap_up_info->uartclk);
1545 	return omap_up_info;
1546 }
1547 
1548 static int serial_omap_probe_rs485(struct uart_omap_port *up,
1549 				   struct device_node *np)
1550 {
1551 	struct serial_rs485 *rs485conf = &up->port.rs485;
1552 	u32 rs485_delay[2];
1553 	enum of_gpio_flags flags;
1554 	int ret;
1555 
1556 	rs485conf->flags = 0;
1557 	up->rts_gpio = -EINVAL;
1558 
1559 	if (!np)
1560 		return 0;
1561 
1562 	if (of_property_read_bool(np, "rs485-rts-active-high"))
1563 		rs485conf->flags |= SER_RS485_RTS_ON_SEND;
1564 	else
1565 		rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
1566 
1567 	/* check for tx enable gpio */
1568 	up->rts_gpio = of_get_named_gpio_flags(np, "rts-gpio", 0, &flags);
1569 	if (gpio_is_valid(up->rts_gpio)) {
1570 		ret = devm_gpio_request(up->dev, up->rts_gpio, "omap-serial");
1571 		if (ret < 0)
1572 			return ret;
1573 		ret = gpio_direction_output(up->rts_gpio,
1574 					    flags & SER_RS485_RTS_AFTER_SEND);
1575 		if (ret < 0)
1576 			return ret;
1577 	} else if (up->rts_gpio == -EPROBE_DEFER) {
1578 		return -EPROBE_DEFER;
1579 	} else {
1580 		up->rts_gpio = -EINVAL;
1581 	}
1582 
1583 	if (of_property_read_u32_array(np, "rs485-rts-delay",
1584 				    rs485_delay, 2) == 0) {
1585 		rs485conf->delay_rts_before_send = rs485_delay[0];
1586 		rs485conf->delay_rts_after_send = rs485_delay[1];
1587 	}
1588 
1589 	if (of_property_read_bool(np, "rs485-rx-during-tx"))
1590 		rs485conf->flags |= SER_RS485_RX_DURING_TX;
1591 
1592 	if (of_property_read_bool(np, "linux,rs485-enabled-at-boot-time"))
1593 		rs485conf->flags |= SER_RS485_ENABLED;
1594 
1595 	return 0;
1596 }
1597 
1598 static int serial_omap_probe(struct platform_device *pdev)
1599 {
1600 	struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
1601 	struct uart_omap_port *up;
1602 	struct resource *mem;
1603 	void __iomem *base;
1604 	int uartirq = 0;
1605 	int wakeirq = 0;
1606 	int ret;
1607 
1608 	/* The optional wakeirq may be specified in the board dts file */
1609 	if (pdev->dev.of_node) {
1610 		uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0);
1611 		if (!uartirq)
1612 			return -EPROBE_DEFER;
1613 		wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
1614 		omap_up_info = of_get_uart_port_info(&pdev->dev);
1615 		pdev->dev.platform_data = omap_up_info;
1616 	} else {
1617 		uartirq = platform_get_irq(pdev, 0);
1618 		if (uartirq < 0)
1619 			return -EPROBE_DEFER;
1620 	}
1621 
1622 	up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
1623 	if (!up)
1624 		return -ENOMEM;
1625 
1626 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1627 	base = devm_ioremap_resource(&pdev->dev, mem);
1628 	if (IS_ERR(base))
1629 		return PTR_ERR(base);
1630 
1631 	up->dev = &pdev->dev;
1632 	up->port.dev = &pdev->dev;
1633 	up->port.type = PORT_OMAP;
1634 	up->port.iotype = UPIO_MEM;
1635 	up->port.irq = uartirq;
1636 	up->port.regshift = 2;
1637 	up->port.fifosize = 64;
1638 	up->port.ops = &serial_omap_pops;
1639 
1640 	if (pdev->dev.of_node)
1641 		ret = of_alias_get_id(pdev->dev.of_node, "serial");
1642 	else
1643 		ret = pdev->id;
1644 
1645 	if (ret < 0) {
1646 		dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1647 			ret);
1648 		goto err_port_line;
1649 	}
1650 	up->port.line = ret;
1651 
1652 	if (up->port.line >= OMAP_MAX_HSUART_PORTS) {
1653 		dev_err(&pdev->dev, "uart ID %d >  MAX %d.\n", up->port.line,
1654 			OMAP_MAX_HSUART_PORTS);
1655 		ret = -ENXIO;
1656 		goto err_port_line;
1657 	}
1658 
1659 	up->wakeirq = wakeirq;
1660 	if (!up->wakeirq)
1661 		dev_info(up->port.dev, "no wakeirq for uart%d\n",
1662 			 up->port.line);
1663 
1664 	ret = serial_omap_probe_rs485(up, pdev->dev.of_node);
1665 	if (ret < 0)
1666 		goto err_rs485;
1667 
1668 	sprintf(up->name, "OMAP UART%d", up->port.line);
1669 	up->port.mapbase = mem->start;
1670 	up->port.membase = base;
1671 	up->port.flags = omap_up_info->flags;
1672 	up->port.uartclk = omap_up_info->uartclk;
1673 	up->port.rs485_config = serial_omap_config_rs485;
1674 	if (!up->port.uartclk) {
1675 		up->port.uartclk = DEFAULT_CLK_SPEED;
1676 		dev_warn(&pdev->dev,
1677 			 "No clock speed specified: using default: %d\n",
1678 			 DEFAULT_CLK_SPEED);
1679 	}
1680 
1681 	up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1682 	up->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1683 	pm_qos_add_request(&up->pm_qos_request,
1684 		PM_QOS_CPU_DMA_LATENCY, up->latency);
1685 	INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1686 
1687 	platform_set_drvdata(pdev, up);
1688 	if (omap_up_info->autosuspend_timeout == 0)
1689 		omap_up_info->autosuspend_timeout = -1;
1690 
1691 	device_init_wakeup(up->dev, true);
1692 	pm_runtime_use_autosuspend(&pdev->dev);
1693 	pm_runtime_set_autosuspend_delay(&pdev->dev,
1694 			omap_up_info->autosuspend_timeout);
1695 
1696 	pm_runtime_irq_safe(&pdev->dev);
1697 	pm_runtime_enable(&pdev->dev);
1698 
1699 	pm_runtime_get_sync(&pdev->dev);
1700 
1701 	omap_serial_fill_features_erratas(up);
1702 
1703 	ui[up->port.line] = up;
1704 	serial_omap_add_console_port(up);
1705 
1706 	ret = uart_add_one_port(&serial_omap_reg, &up->port);
1707 	if (ret != 0)
1708 		goto err_add_port;
1709 
1710 	pm_runtime_mark_last_busy(up->dev);
1711 	pm_runtime_put_autosuspend(up->dev);
1712 	return 0;
1713 
1714 err_add_port:
1715 	pm_runtime_put(&pdev->dev);
1716 	pm_runtime_disable(&pdev->dev);
1717 	pm_qos_remove_request(&up->pm_qos_request);
1718 	device_init_wakeup(up->dev, false);
1719 err_rs485:
1720 err_port_line:
1721 	return ret;
1722 }
1723 
1724 static int serial_omap_remove(struct platform_device *dev)
1725 {
1726 	struct uart_omap_port *up = platform_get_drvdata(dev);
1727 
1728 	pm_runtime_put_sync(up->dev);
1729 	pm_runtime_disable(up->dev);
1730 	uart_remove_one_port(&serial_omap_reg, &up->port);
1731 	pm_qos_remove_request(&up->pm_qos_request);
1732 	device_init_wakeup(&dev->dev, false);
1733 
1734 	return 0;
1735 }
1736 
1737 /*
1738  * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1739  * The access to uart register after MDR1 Access
1740  * causes UART to corrupt data.
1741  *
1742  * Need a delay =
1743  * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1744  * give 10 times as much
1745  */
1746 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1747 {
1748 	u8 timeout = 255;
1749 
1750 	serial_out(up, UART_OMAP_MDR1, mdr1);
1751 	udelay(2);
1752 	serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1753 			UART_FCR_CLEAR_RCVR);
1754 	/*
1755 	 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1756 	 * TX_FIFO_E bit is 1.
1757 	 */
1758 	while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1759 				(UART_LSR_THRE | UART_LSR_DR))) {
1760 		timeout--;
1761 		if (!timeout) {
1762 			/* Should *never* happen. we warn and carry on */
1763 			dev_crit(up->dev, "Errata i202: timedout %x\n",
1764 						serial_in(up, UART_LSR));
1765 			break;
1766 		}
1767 		udelay(1);
1768 	}
1769 }
1770 
1771 #ifdef CONFIG_PM
1772 static void serial_omap_restore_context(struct uart_omap_port *up)
1773 {
1774 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1775 		serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1776 	else
1777 		serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1778 
1779 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1780 	serial_out(up, UART_EFR, UART_EFR_ECB);
1781 	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1782 	serial_out(up, UART_IER, 0x0);
1783 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1784 	serial_out(up, UART_DLL, up->dll);
1785 	serial_out(up, UART_DLM, up->dlh);
1786 	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1787 	serial_out(up, UART_IER, up->ier);
1788 	serial_out(up, UART_FCR, up->fcr);
1789 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1790 	serial_out(up, UART_MCR, up->mcr);
1791 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1792 	serial_out(up, UART_OMAP_SCR, up->scr);
1793 	serial_out(up, UART_EFR, up->efr);
1794 	serial_out(up, UART_LCR, up->lcr);
1795 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1796 		serial_omap_mdr1_errataset(up, up->mdr1);
1797 	else
1798 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1799 	serial_out(up, UART_OMAP_WER, up->wer);
1800 }
1801 
1802 static int serial_omap_runtime_suspend(struct device *dev)
1803 {
1804 	struct uart_omap_port *up = dev_get_drvdata(dev);
1805 
1806 	if (!up)
1807 		return -EINVAL;
1808 
1809 	/*
1810 	* When using 'no_console_suspend', the console UART must not be
1811 	* suspended. Since driver suspend is managed by runtime suspend,
1812 	* preventing runtime suspend (by returning error) will keep device
1813 	* active during suspend.
1814 	*/
1815 	if (up->is_suspending && !console_suspend_enabled &&
1816 	    uart_console(&up->port))
1817 		return -EBUSY;
1818 
1819 	up->context_loss_cnt = serial_omap_get_context_loss_count(up);
1820 
1821 	serial_omap_enable_wakeup(up, true);
1822 
1823 	up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1824 	schedule_work(&up->qos_work);
1825 
1826 	return 0;
1827 }
1828 
1829 static int serial_omap_runtime_resume(struct device *dev)
1830 {
1831 	struct uart_omap_port *up = dev_get_drvdata(dev);
1832 
1833 	int loss_cnt = serial_omap_get_context_loss_count(up);
1834 
1835 	serial_omap_enable_wakeup(up, false);
1836 
1837 	if (loss_cnt < 0) {
1838 		dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
1839 			loss_cnt);
1840 		serial_omap_restore_context(up);
1841 	} else if (up->context_loss_cnt != loss_cnt) {
1842 		serial_omap_restore_context(up);
1843 	}
1844 	up->latency = up->calc_latency;
1845 	schedule_work(&up->qos_work);
1846 
1847 	return 0;
1848 }
1849 #endif
1850 
1851 static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1852 	SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1853 	SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1854 				serial_omap_runtime_resume, NULL)
1855 	.prepare        = serial_omap_prepare,
1856 	.complete       = serial_omap_complete,
1857 };
1858 
1859 #if defined(CONFIG_OF)
1860 static const struct of_device_id omap_serial_of_match[] = {
1861 	{ .compatible = "ti,omap2-uart" },
1862 	{ .compatible = "ti,omap3-uart" },
1863 	{ .compatible = "ti,omap4-uart" },
1864 	{},
1865 };
1866 MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1867 #endif
1868 
1869 static struct platform_driver serial_omap_driver = {
1870 	.probe          = serial_omap_probe,
1871 	.remove         = serial_omap_remove,
1872 	.driver		= {
1873 		.name	= OMAP_SERIAL_DRIVER_NAME,
1874 		.pm	= &serial_omap_dev_pm_ops,
1875 		.of_match_table = of_match_ptr(omap_serial_of_match),
1876 	},
1877 };
1878 
1879 static int __init serial_omap_init(void)
1880 {
1881 	int ret;
1882 
1883 	ret = uart_register_driver(&serial_omap_reg);
1884 	if (ret != 0)
1885 		return ret;
1886 	ret = platform_driver_register(&serial_omap_driver);
1887 	if (ret != 0)
1888 		uart_unregister_driver(&serial_omap_reg);
1889 	return ret;
1890 }
1891 
1892 static void __exit serial_omap_exit(void)
1893 {
1894 	platform_driver_unregister(&serial_omap_driver);
1895 	uart_unregister_driver(&serial_omap_reg);
1896 }
1897 
1898 module_init(serial_omap_init);
1899 module_exit(serial_omap_exit);
1900 
1901 MODULE_DESCRIPTION("OMAP High Speed UART driver");
1902 MODULE_LICENSE("GPL");
1903 MODULE_AUTHOR("Texas Instruments Inc");
1904