xref: /linux/drivers/tty/serial/omap-serial.c (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
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 static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
203 {
204 	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
205 
206 	if (!pdata || !pdata->get_context_loss_count)
207 		return -EINVAL;
208 
209 	return pdata->get_context_loss_count(up->dev);
210 }
211 
212 /* REVISIT: Remove this when omap3 boots in device tree only mode */
213 static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
214 {
215 	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
216 
217 	if (!pdata || !pdata->enable_wakeup)
218 		return;
219 
220 	pdata->enable_wakeup(up->dev, enable);
221 }
222 
223 /*
224  * Calculate the absolute difference between the desired and actual baud
225  * rate for the given mode.
226  */
227 static inline int calculate_baud_abs_diff(struct uart_port *port,
228 				unsigned int baud, unsigned int mode)
229 {
230 	unsigned int n = port->uartclk / (mode * baud);
231 	int abs_diff;
232 
233 	if (n == 0)
234 		n = 1;
235 
236 	abs_diff = baud - (port->uartclk / (mode * n));
237 	if (abs_diff < 0)
238 		abs_diff = -abs_diff;
239 
240 	return abs_diff;
241 }
242 
243 /*
244  * serial_omap_baud_is_mode16 - check if baud rate is MODE16X
245  * @port: uart port info
246  * @baud: baudrate for which mode needs to be determined
247  *
248  * Returns true if baud rate is MODE16X and false if MODE13X
249  * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
250  * and Error Rates" determines modes not for all common baud rates.
251  * E.g. for 1000000 baud rate mode must be 16x, but according to that
252  * table it's determined as 13x.
253  */
254 static bool
255 serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
256 {
257 	int abs_diff_13 = calculate_baud_abs_diff(port, baud, 13);
258 	int abs_diff_16 = calculate_baud_abs_diff(port, baud, 16);
259 
260 	return (abs_diff_13 >= abs_diff_16);
261 }
262 
263 /*
264  * serial_omap_get_divisor - calculate divisor value
265  * @port: uart port info
266  * @baud: baudrate for which divisor needs to be calculated.
267  */
268 static unsigned int
269 serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
270 {
271 	unsigned int mode;
272 
273 	if (!serial_omap_baud_is_mode16(port, baud))
274 		mode = 13;
275 	else
276 		mode = 16;
277 	return port->uartclk/(mode * baud);
278 }
279 
280 static void serial_omap_enable_ms(struct uart_port *port)
281 {
282 	struct uart_omap_port *up = to_uart_omap_port(port);
283 
284 	dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
285 
286 	pm_runtime_get_sync(up->dev);
287 	up->ier |= UART_IER_MSI;
288 	serial_out(up, UART_IER, up->ier);
289 	pm_runtime_mark_last_busy(up->dev);
290 	pm_runtime_put_autosuspend(up->dev);
291 }
292 
293 static void serial_omap_stop_tx(struct uart_port *port)
294 {
295 	struct uart_omap_port *up = to_uart_omap_port(port);
296 	int res;
297 
298 	pm_runtime_get_sync(up->dev);
299 
300 	/* Handle RS-485 */
301 	if (port->rs485.flags & SER_RS485_ENABLED) {
302 		if (up->scr & OMAP_UART_SCR_TX_EMPTY) {
303 			/* THR interrupt is fired when both TX FIFO and TX
304 			 * shift register are empty. This means there's nothing
305 			 * left to transmit now, so make sure the THR interrupt
306 			 * is fired when TX FIFO is below the trigger level,
307 			 * disable THR interrupts and toggle the RS-485 GPIO
308 			 * data direction pin if needed.
309 			 */
310 			up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
311 			serial_out(up, UART_OMAP_SCR, up->scr);
312 			res = (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) ?
313 				1 : 0;
314 			if (gpio_get_value(up->rts_gpio) != res) {
315 				if (port->rs485.delay_rts_after_send > 0)
316 					mdelay(
317 					port->rs485.delay_rts_after_send);
318 				gpio_set_value(up->rts_gpio, res);
319 			}
320 		} else {
321 			/* We're asked to stop, but there's still stuff in the
322 			 * UART FIFO, so make sure the THR interrupt is fired
323 			 * when both TX FIFO and TX shift register are empty.
324 			 * The next THR interrupt (if no transmission is started
325 			 * in the meantime) will indicate the end of a
326 			 * transmission. Therefore we _don't_ disable THR
327 			 * interrupts in this situation.
328 			 */
329 			up->scr |= OMAP_UART_SCR_TX_EMPTY;
330 			serial_out(up, UART_OMAP_SCR, up->scr);
331 			return;
332 		}
333 	}
334 
335 	if (up->ier & UART_IER_THRI) {
336 		up->ier &= ~UART_IER_THRI;
337 		serial_out(up, UART_IER, up->ier);
338 	}
339 
340 	if ((port->rs485.flags & SER_RS485_ENABLED) &&
341 	    !(port->rs485.flags & SER_RS485_RX_DURING_TX)) {
342 		/*
343 		 * Empty the RX FIFO, we are not interested in anything
344 		 * received during the half-duplex transmission.
345 		 */
346 		serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_RCVR);
347 		/* Re-enable RX interrupts */
348 		up->ier |= UART_IER_RLSI | UART_IER_RDI;
349 		up->port.read_status_mask |= UART_LSR_DR;
350 		serial_out(up, UART_IER, up->ier);
351 	}
352 
353 	pm_runtime_mark_last_busy(up->dev);
354 	pm_runtime_put_autosuspend(up->dev);
355 }
356 
357 static void serial_omap_stop_rx(struct uart_port *port)
358 {
359 	struct uart_omap_port *up = to_uart_omap_port(port);
360 
361 	pm_runtime_get_sync(up->dev);
362 	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
363 	up->port.read_status_mask &= ~UART_LSR_DR;
364 	serial_out(up, UART_IER, up->ier);
365 	pm_runtime_mark_last_busy(up->dev);
366 	pm_runtime_put_autosuspend(up->dev);
367 }
368 
369 static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
370 {
371 	struct circ_buf *xmit = &up->port.state->xmit;
372 	int count;
373 
374 	if (up->port.x_char) {
375 		serial_out(up, UART_TX, up->port.x_char);
376 		up->port.icount.tx++;
377 		up->port.x_char = 0;
378 		return;
379 	}
380 	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
381 		serial_omap_stop_tx(&up->port);
382 		return;
383 	}
384 	count = up->port.fifosize / 4;
385 	do {
386 		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
387 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
388 		up->port.icount.tx++;
389 		if (uart_circ_empty(xmit))
390 			break;
391 	} while (--count > 0);
392 
393 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
394 		uart_write_wakeup(&up->port);
395 
396 	if (uart_circ_empty(xmit))
397 		serial_omap_stop_tx(&up->port);
398 }
399 
400 static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
401 {
402 	if (!(up->ier & UART_IER_THRI)) {
403 		up->ier |= UART_IER_THRI;
404 		serial_out(up, UART_IER, up->ier);
405 	}
406 }
407 
408 static void serial_omap_start_tx(struct uart_port *port)
409 {
410 	struct uart_omap_port *up = to_uart_omap_port(port);
411 	int res;
412 
413 	pm_runtime_get_sync(up->dev);
414 
415 	/* Handle RS-485 */
416 	if (port->rs485.flags & SER_RS485_ENABLED) {
417 		/* Fire THR interrupts when FIFO is below trigger level */
418 		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
419 		serial_out(up, UART_OMAP_SCR, up->scr);
420 
421 		/* if rts not already enabled */
422 		res = (port->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
423 		if (gpio_get_value(up->rts_gpio) != res) {
424 			gpio_set_value(up->rts_gpio, res);
425 			if (port->rs485.delay_rts_before_send > 0)
426 				mdelay(port->rs485.delay_rts_before_send);
427 		}
428 	}
429 
430 	if ((port->rs485.flags & SER_RS485_ENABLED) &&
431 	    !(port->rs485.flags & SER_RS485_RX_DURING_TX))
432 		serial_omap_stop_rx(port);
433 
434 	serial_omap_enable_ier_thri(up);
435 	pm_runtime_mark_last_busy(up->dev);
436 	pm_runtime_put_autosuspend(up->dev);
437 }
438 
439 static void serial_omap_throttle(struct uart_port *port)
440 {
441 	struct uart_omap_port *up = to_uart_omap_port(port);
442 	unsigned long flags;
443 
444 	pm_runtime_get_sync(up->dev);
445 	spin_lock_irqsave(&up->port.lock, flags);
446 	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
447 	serial_out(up, UART_IER, up->ier);
448 	spin_unlock_irqrestore(&up->port.lock, flags);
449 	pm_runtime_mark_last_busy(up->dev);
450 	pm_runtime_put_autosuspend(up->dev);
451 }
452 
453 static void serial_omap_unthrottle(struct uart_port *port)
454 {
455 	struct uart_omap_port *up = to_uart_omap_port(port);
456 	unsigned long flags;
457 
458 	pm_runtime_get_sync(up->dev);
459 	spin_lock_irqsave(&up->port.lock, flags);
460 	up->ier |= UART_IER_RLSI | UART_IER_RDI;
461 	serial_out(up, UART_IER, up->ier);
462 	spin_unlock_irqrestore(&up->port.lock, flags);
463 	pm_runtime_mark_last_busy(up->dev);
464 	pm_runtime_put_autosuspend(up->dev);
465 }
466 
467 static unsigned int check_modem_status(struct uart_omap_port *up)
468 {
469 	unsigned int status;
470 
471 	status = serial_in(up, UART_MSR);
472 	status |= up->msr_saved_flags;
473 	up->msr_saved_flags = 0;
474 	if ((status & UART_MSR_ANY_DELTA) == 0)
475 		return status;
476 
477 	if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
478 	    up->port.state != NULL) {
479 		if (status & UART_MSR_TERI)
480 			up->port.icount.rng++;
481 		if (status & UART_MSR_DDSR)
482 			up->port.icount.dsr++;
483 		if (status & UART_MSR_DDCD)
484 			uart_handle_dcd_change
485 				(&up->port, status & UART_MSR_DCD);
486 		if (status & UART_MSR_DCTS)
487 			uart_handle_cts_change
488 				(&up->port, status & UART_MSR_CTS);
489 		wake_up_interruptible(&up->port.state->port.delta_msr_wait);
490 	}
491 
492 	return status;
493 }
494 
495 static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
496 {
497 	unsigned int flag;
498 	unsigned char ch = 0;
499 
500 	if (likely(lsr & UART_LSR_DR))
501 		ch = serial_in(up, UART_RX);
502 
503 	up->port.icount.rx++;
504 	flag = TTY_NORMAL;
505 
506 	if (lsr & UART_LSR_BI) {
507 		flag = TTY_BREAK;
508 		lsr &= ~(UART_LSR_FE | UART_LSR_PE);
509 		up->port.icount.brk++;
510 		/*
511 		 * We do the SysRQ and SAK checking
512 		 * here because otherwise the break
513 		 * may get masked by ignore_status_mask
514 		 * or read_status_mask.
515 		 */
516 		if (uart_handle_break(&up->port))
517 			return;
518 
519 	}
520 
521 	if (lsr & UART_LSR_PE) {
522 		flag = TTY_PARITY;
523 		up->port.icount.parity++;
524 	}
525 
526 	if (lsr & UART_LSR_FE) {
527 		flag = TTY_FRAME;
528 		up->port.icount.frame++;
529 	}
530 
531 	if (lsr & UART_LSR_OE)
532 		up->port.icount.overrun++;
533 
534 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
535 	if (up->port.line == up->port.cons->index) {
536 		/* Recover the break flag from console xmit */
537 		lsr |= up->lsr_break_flag;
538 	}
539 #endif
540 	uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag);
541 }
542 
543 static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
544 {
545 	unsigned char ch = 0;
546 	unsigned int flag;
547 
548 	if (!(lsr & UART_LSR_DR))
549 		return;
550 
551 	ch = serial_in(up, UART_RX);
552 	flag = TTY_NORMAL;
553 	up->port.icount.rx++;
554 
555 	if (uart_handle_sysrq_char(&up->port, ch))
556 		return;
557 
558 	uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
559 }
560 
561 /**
562  * serial_omap_irq() - This handles the interrupt from one port
563  * @irq: uart port irq number
564  * @dev_id: uart port info
565  */
566 static irqreturn_t serial_omap_irq(int irq, void *dev_id)
567 {
568 	struct uart_omap_port *up = dev_id;
569 	unsigned int iir, lsr;
570 	unsigned int type;
571 	irqreturn_t ret = IRQ_NONE;
572 	int max_count = 256;
573 
574 	spin_lock(&up->port.lock);
575 	pm_runtime_get_sync(up->dev);
576 
577 	do {
578 		iir = serial_in(up, UART_IIR);
579 		if (iir & UART_IIR_NO_INT)
580 			break;
581 
582 		ret = IRQ_HANDLED;
583 		lsr = serial_in(up, UART_LSR);
584 
585 		/* extract IRQ type from IIR register */
586 		type = iir & 0x3e;
587 
588 		switch (type) {
589 		case UART_IIR_MSI:
590 			check_modem_status(up);
591 			break;
592 		case UART_IIR_THRI:
593 			transmit_chars(up, lsr);
594 			break;
595 		case UART_IIR_RX_TIMEOUT:
596 			/* FALLTHROUGH */
597 		case UART_IIR_RDI:
598 			serial_omap_rdi(up, lsr);
599 			break;
600 		case UART_IIR_RLSI:
601 			serial_omap_rlsi(up, lsr);
602 			break;
603 		case UART_IIR_CTS_RTS_DSR:
604 			/* simply try again */
605 			break;
606 		case UART_IIR_XOFF:
607 			/* FALLTHROUGH */
608 		default:
609 			break;
610 		}
611 	} while (!(iir & UART_IIR_NO_INT) && max_count--);
612 
613 	spin_unlock(&up->port.lock);
614 
615 	tty_flip_buffer_push(&up->port.state->port);
616 
617 	pm_runtime_mark_last_busy(up->dev);
618 	pm_runtime_put_autosuspend(up->dev);
619 	up->port_activity = jiffies;
620 
621 	return ret;
622 }
623 
624 static unsigned int serial_omap_tx_empty(struct uart_port *port)
625 {
626 	struct uart_omap_port *up = to_uart_omap_port(port);
627 	unsigned long flags = 0;
628 	unsigned int ret = 0;
629 
630 	pm_runtime_get_sync(up->dev);
631 	dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
632 	spin_lock_irqsave(&up->port.lock, flags);
633 	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
634 	spin_unlock_irqrestore(&up->port.lock, flags);
635 	pm_runtime_mark_last_busy(up->dev);
636 	pm_runtime_put_autosuspend(up->dev);
637 	return ret;
638 }
639 
640 static unsigned int serial_omap_get_mctrl(struct uart_port *port)
641 {
642 	struct uart_omap_port *up = to_uart_omap_port(port);
643 	unsigned int status;
644 	unsigned int ret = 0;
645 
646 	pm_runtime_get_sync(up->dev);
647 	status = check_modem_status(up);
648 	pm_runtime_mark_last_busy(up->dev);
649 	pm_runtime_put_autosuspend(up->dev);
650 
651 	dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
652 
653 	if (status & UART_MSR_DCD)
654 		ret |= TIOCM_CAR;
655 	if (status & UART_MSR_RI)
656 		ret |= TIOCM_RNG;
657 	if (status & UART_MSR_DSR)
658 		ret |= TIOCM_DSR;
659 	if (status & UART_MSR_CTS)
660 		ret |= TIOCM_CTS;
661 	return ret;
662 }
663 
664 static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
665 {
666 	struct uart_omap_port *up = to_uart_omap_port(port);
667 	unsigned char mcr = 0, old_mcr, lcr;
668 
669 	dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
670 	if (mctrl & TIOCM_RTS)
671 		mcr |= UART_MCR_RTS;
672 	if (mctrl & TIOCM_DTR)
673 		mcr |= UART_MCR_DTR;
674 	if (mctrl & TIOCM_OUT1)
675 		mcr |= UART_MCR_OUT1;
676 	if (mctrl & TIOCM_OUT2)
677 		mcr |= UART_MCR_OUT2;
678 	if (mctrl & TIOCM_LOOP)
679 		mcr |= UART_MCR_LOOP;
680 
681 	pm_runtime_get_sync(up->dev);
682 	old_mcr = serial_in(up, UART_MCR);
683 	old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
684 		     UART_MCR_DTR | UART_MCR_RTS);
685 	up->mcr = old_mcr | mcr;
686 	serial_out(up, UART_MCR, up->mcr);
687 
688 	/* Turn off autoRTS if RTS is lowered; restore autoRTS if RTS raised */
689 	lcr = serial_in(up, UART_LCR);
690 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
691 	if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS))
692 		up->efr |= UART_EFR_RTS;
693 	else
694 		up->efr &= UART_EFR_RTS;
695 	serial_out(up, UART_EFR, up->efr);
696 	serial_out(up, UART_LCR, lcr);
697 
698 	pm_runtime_mark_last_busy(up->dev);
699 	pm_runtime_put_autosuspend(up->dev);
700 }
701 
702 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
703 {
704 	struct uart_omap_port *up = to_uart_omap_port(port);
705 	unsigned long flags = 0;
706 
707 	dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
708 	pm_runtime_get_sync(up->dev);
709 	spin_lock_irqsave(&up->port.lock, flags);
710 	if (break_state == -1)
711 		up->lcr |= UART_LCR_SBC;
712 	else
713 		up->lcr &= ~UART_LCR_SBC;
714 	serial_out(up, UART_LCR, up->lcr);
715 	spin_unlock_irqrestore(&up->port.lock, flags);
716 	pm_runtime_mark_last_busy(up->dev);
717 	pm_runtime_put_autosuspend(up->dev);
718 }
719 
720 static int serial_omap_startup(struct uart_port *port)
721 {
722 	struct uart_omap_port *up = to_uart_omap_port(port);
723 	unsigned long flags = 0;
724 	int retval;
725 
726 	/*
727 	 * Allocate the IRQ
728 	 */
729 	retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
730 				up->name, up);
731 	if (retval)
732 		return retval;
733 
734 	/* Optional wake-up IRQ */
735 	if (up->wakeirq) {
736 		retval = dev_pm_set_dedicated_wake_irq(up->dev, up->wakeirq);
737 		if (retval) {
738 			free_irq(up->port.irq, up);
739 			return retval;
740 		}
741 	}
742 
743 	dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
744 
745 	pm_runtime_get_sync(up->dev);
746 	/*
747 	 * Clear the FIFO buffers and disable them.
748 	 * (they will be reenabled in set_termios())
749 	 */
750 	serial_omap_clear_fifos(up);
751 
752 	/*
753 	 * Clear the interrupt registers.
754 	 */
755 	(void) serial_in(up, UART_LSR);
756 	if (serial_in(up, UART_LSR) & UART_LSR_DR)
757 		(void) serial_in(up, UART_RX);
758 	(void) serial_in(up, UART_IIR);
759 	(void) serial_in(up, UART_MSR);
760 
761 	/*
762 	 * Now, initialize the UART
763 	 */
764 	serial_out(up, UART_LCR, UART_LCR_WLEN8);
765 	spin_lock_irqsave(&up->port.lock, flags);
766 	/*
767 	 * Most PC uarts need OUT2 raised to enable interrupts.
768 	 */
769 	up->port.mctrl |= TIOCM_OUT2;
770 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
771 	spin_unlock_irqrestore(&up->port.lock, flags);
772 
773 	up->msr_saved_flags = 0;
774 	/*
775 	 * Finally, enable interrupts. Note: Modem status interrupts
776 	 * are set via set_termios(), which will be occurring imminently
777 	 * anyway, so we don't enable them here.
778 	 */
779 	up->ier = UART_IER_RLSI | UART_IER_RDI;
780 	serial_out(up, UART_IER, up->ier);
781 
782 	/* Enable module level wake up */
783 	up->wer = OMAP_UART_WER_MOD_WKUP;
784 	if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
785 		up->wer |= OMAP_UART_TX_WAKEUP_EN;
786 
787 	serial_out(up, UART_OMAP_WER, up->wer);
788 
789 	pm_runtime_mark_last_busy(up->dev);
790 	pm_runtime_put_autosuspend(up->dev);
791 	up->port_activity = jiffies;
792 	return 0;
793 }
794 
795 static void serial_omap_shutdown(struct uart_port *port)
796 {
797 	struct uart_omap_port *up = to_uart_omap_port(port);
798 	unsigned long flags = 0;
799 
800 	dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
801 
802 	pm_runtime_get_sync(up->dev);
803 	/*
804 	 * Disable interrupts from this port
805 	 */
806 	up->ier = 0;
807 	serial_out(up, UART_IER, 0);
808 
809 	spin_lock_irqsave(&up->port.lock, flags);
810 	up->port.mctrl &= ~TIOCM_OUT2;
811 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
812 	spin_unlock_irqrestore(&up->port.lock, flags);
813 
814 	/*
815 	 * Disable break condition and FIFOs
816 	 */
817 	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
818 	serial_omap_clear_fifos(up);
819 
820 	/*
821 	 * Read data port to reset things, and then free the irq
822 	 */
823 	if (serial_in(up, UART_LSR) & UART_LSR_DR)
824 		(void) serial_in(up, UART_RX);
825 
826 	pm_runtime_mark_last_busy(up->dev);
827 	pm_runtime_put_autosuspend(up->dev);
828 	free_irq(up->port.irq, up);
829 	dev_pm_clear_wake_irq(up->dev);
830 }
831 
832 static void serial_omap_uart_qos_work(struct work_struct *work)
833 {
834 	struct uart_omap_port *up = container_of(work, struct uart_omap_port,
835 						qos_work);
836 
837 	pm_qos_update_request(&up->pm_qos_request, up->latency);
838 }
839 
840 static void
841 serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
842 			struct ktermios *old)
843 {
844 	struct uart_omap_port *up = to_uart_omap_port(port);
845 	unsigned char cval = 0;
846 	unsigned long flags = 0;
847 	unsigned int baud, quot;
848 
849 	switch (termios->c_cflag & CSIZE) {
850 	case CS5:
851 		cval = UART_LCR_WLEN5;
852 		break;
853 	case CS6:
854 		cval = UART_LCR_WLEN6;
855 		break;
856 	case CS7:
857 		cval = UART_LCR_WLEN7;
858 		break;
859 	default:
860 	case CS8:
861 		cval = UART_LCR_WLEN8;
862 		break;
863 	}
864 
865 	if (termios->c_cflag & CSTOPB)
866 		cval |= UART_LCR_STOP;
867 	if (termios->c_cflag & PARENB)
868 		cval |= UART_LCR_PARITY;
869 	if (!(termios->c_cflag & PARODD))
870 		cval |= UART_LCR_EPAR;
871 	if (termios->c_cflag & CMSPAR)
872 		cval |= UART_LCR_SPAR;
873 
874 	/*
875 	 * Ask the core to calculate the divisor for us.
876 	 */
877 
878 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
879 	quot = serial_omap_get_divisor(port, baud);
880 
881 	/* calculate wakeup latency constraint */
882 	up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
883 	up->latency = up->calc_latency;
884 	schedule_work(&up->qos_work);
885 
886 	up->dll = quot & 0xff;
887 	up->dlh = quot >> 8;
888 	up->mdr1 = UART_OMAP_MDR1_DISABLE;
889 
890 	up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
891 			UART_FCR_ENABLE_FIFO;
892 
893 	/*
894 	 * Ok, we're now changing the port state. Do it with
895 	 * interrupts disabled.
896 	 */
897 	pm_runtime_get_sync(up->dev);
898 	spin_lock_irqsave(&up->port.lock, flags);
899 
900 	/*
901 	 * Update the per-port timeout.
902 	 */
903 	uart_update_timeout(port, termios->c_cflag, baud);
904 
905 	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
906 	if (termios->c_iflag & INPCK)
907 		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
908 	if (termios->c_iflag & (BRKINT | PARMRK))
909 		up->port.read_status_mask |= UART_LSR_BI;
910 
911 	/*
912 	 * Characters to ignore
913 	 */
914 	up->port.ignore_status_mask = 0;
915 	if (termios->c_iflag & IGNPAR)
916 		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
917 	if (termios->c_iflag & IGNBRK) {
918 		up->port.ignore_status_mask |= UART_LSR_BI;
919 		/*
920 		 * If we're ignoring parity and break indicators,
921 		 * ignore overruns too (for real raw support).
922 		 */
923 		if (termios->c_iflag & IGNPAR)
924 			up->port.ignore_status_mask |= UART_LSR_OE;
925 	}
926 
927 	/*
928 	 * ignore all characters if CREAD is not set
929 	 */
930 	if ((termios->c_cflag & CREAD) == 0)
931 		up->port.ignore_status_mask |= UART_LSR_DR;
932 
933 	/*
934 	 * Modem status interrupts
935 	 */
936 	up->ier &= ~UART_IER_MSI;
937 	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
938 		up->ier |= UART_IER_MSI;
939 	serial_out(up, UART_IER, up->ier);
940 	serial_out(up, UART_LCR, cval);		/* reset DLAB */
941 	up->lcr = cval;
942 	up->scr = 0;
943 
944 	/* FIFOs and DMA Settings */
945 
946 	/* FCR can be changed only when the
947 	 * baud clock is not running
948 	 * DLL_REG and DLH_REG set to 0.
949 	 */
950 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
951 	serial_out(up, UART_DLL, 0);
952 	serial_out(up, UART_DLM, 0);
953 	serial_out(up, UART_LCR, 0);
954 
955 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
956 
957 	up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
958 	up->efr &= ~UART_EFR_SCD;
959 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
960 
961 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
962 	up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
963 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
964 	/* FIFO ENABLE, DMA MODE */
965 
966 	up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
967 	/*
968 	 * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
969 	 * sets Enables the granularity of 1 for TRIGGER RX
970 	 * level. Along with setting RX FIFO trigger level
971 	 * to 1 (as noted below, 16 characters) and TLR[3:0]
972 	 * to zero this will result RX FIFO threshold level
973 	 * to 1 character, instead of 16 as noted in comment
974 	 * below.
975 	 */
976 
977 	/* Set receive FIFO threshold to 16 characters and
978 	 * transmit FIFO threshold to 32 spaces
979 	 */
980 	up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
981 	up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
982 	up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
983 		UART_FCR_ENABLE_FIFO;
984 
985 	serial_out(up, UART_FCR, up->fcr);
986 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
987 
988 	serial_out(up, UART_OMAP_SCR, up->scr);
989 
990 	/* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
991 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
992 	serial_out(up, UART_MCR, up->mcr);
993 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
994 	serial_out(up, UART_EFR, up->efr);
995 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
996 
997 	/* Protocol, Baud Rate, and Interrupt Settings */
998 
999 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1000 		serial_omap_mdr1_errataset(up, up->mdr1);
1001 	else
1002 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1003 
1004 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1005 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1006 
1007 	serial_out(up, UART_LCR, 0);
1008 	serial_out(up, UART_IER, 0);
1009 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1010 
1011 	serial_out(up, UART_DLL, up->dll);	/* LS of divisor */
1012 	serial_out(up, UART_DLM, up->dlh);	/* MS of divisor */
1013 
1014 	serial_out(up, UART_LCR, 0);
1015 	serial_out(up, UART_IER, up->ier);
1016 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1017 
1018 	serial_out(up, UART_EFR, up->efr);
1019 	serial_out(up, UART_LCR, cval);
1020 
1021 	if (!serial_omap_baud_is_mode16(port, baud))
1022 		up->mdr1 = UART_OMAP_MDR1_13X_MODE;
1023 	else
1024 		up->mdr1 = UART_OMAP_MDR1_16X_MODE;
1025 
1026 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1027 		serial_omap_mdr1_errataset(up, up->mdr1);
1028 	else
1029 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1030 
1031 	/* Configure flow control */
1032 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1033 
1034 	/* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
1035 	serial_out(up, UART_XON1, termios->c_cc[VSTART]);
1036 	serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
1037 
1038 	/* Enable access to TCR/TLR */
1039 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1040 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1041 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
1042 
1043 	serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
1044 
1045 	up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
1046 
1047 	if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
1048 		/* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */
1049 		up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
1050 		up->efr |= UART_EFR_CTS;
1051 	} else {
1052 		/* Disable AUTORTS and AUTOCTS */
1053 		up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
1054 	}
1055 
1056 	if (up->port.flags & UPF_SOFT_FLOW) {
1057 		/* clear SW control mode bits */
1058 		up->efr &= OMAP_UART_SW_CLR;
1059 
1060 		/*
1061 		 * IXON Flag:
1062 		 * Enable XON/XOFF flow control on input.
1063 		 * Receiver compares XON1, XOFF1.
1064 		 */
1065 		if (termios->c_iflag & IXON)
1066 			up->efr |= OMAP_UART_SW_RX;
1067 
1068 		/*
1069 		 * IXOFF Flag:
1070 		 * Enable XON/XOFF flow control on output.
1071 		 * Transmit XON1, XOFF1
1072 		 */
1073 		if (termios->c_iflag & IXOFF) {
1074 			up->port.status |= UPSTAT_AUTOXOFF;
1075 			up->efr |= OMAP_UART_SW_TX;
1076 		}
1077 
1078 		/*
1079 		 * IXANY Flag:
1080 		 * Enable any character to restart output.
1081 		 * Operation resumes after receiving any
1082 		 * character after recognition of the XOFF character
1083 		 */
1084 		if (termios->c_iflag & IXANY)
1085 			up->mcr |= UART_MCR_XONANY;
1086 		else
1087 			up->mcr &= ~UART_MCR_XONANY;
1088 	}
1089 	serial_out(up, UART_MCR, up->mcr);
1090 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1091 	serial_out(up, UART_EFR, up->efr);
1092 	serial_out(up, UART_LCR, up->lcr);
1093 
1094 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
1095 
1096 	spin_unlock_irqrestore(&up->port.lock, flags);
1097 	pm_runtime_mark_last_busy(up->dev);
1098 	pm_runtime_put_autosuspend(up->dev);
1099 	dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
1100 }
1101 
1102 static void
1103 serial_omap_pm(struct uart_port *port, unsigned int state,
1104 	       unsigned int oldstate)
1105 {
1106 	struct uart_omap_port *up = to_uart_omap_port(port);
1107 	unsigned char efr;
1108 
1109 	dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
1110 
1111 	pm_runtime_get_sync(up->dev);
1112 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1113 	efr = serial_in(up, UART_EFR);
1114 	serial_out(up, UART_EFR, efr | UART_EFR_ECB);
1115 	serial_out(up, UART_LCR, 0);
1116 
1117 	serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
1118 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1119 	serial_out(up, UART_EFR, efr);
1120 	serial_out(up, UART_LCR, 0);
1121 
1122 	pm_runtime_mark_last_busy(up->dev);
1123 	pm_runtime_put_autosuspend(up->dev);
1124 }
1125 
1126 static void serial_omap_release_port(struct uart_port *port)
1127 {
1128 	dev_dbg(port->dev, "serial_omap_release_port+\n");
1129 }
1130 
1131 static int serial_omap_request_port(struct uart_port *port)
1132 {
1133 	dev_dbg(port->dev, "serial_omap_request_port+\n");
1134 	return 0;
1135 }
1136 
1137 static void serial_omap_config_port(struct uart_port *port, int flags)
1138 {
1139 	struct uart_omap_port *up = to_uart_omap_port(port);
1140 
1141 	dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
1142 							up->port.line);
1143 	up->port.type = PORT_OMAP;
1144 	up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
1145 }
1146 
1147 static int
1148 serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
1149 {
1150 	/* we don't want the core code to modify any port params */
1151 	dev_dbg(port->dev, "serial_omap_verify_port+\n");
1152 	return -EINVAL;
1153 }
1154 
1155 static const char *
1156 serial_omap_type(struct uart_port *port)
1157 {
1158 	struct uart_omap_port *up = to_uart_omap_port(port);
1159 
1160 	dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
1161 	return up->name;
1162 }
1163 
1164 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1165 
1166 static inline void wait_for_xmitr(struct uart_omap_port *up)
1167 {
1168 	unsigned int status, tmout = 10000;
1169 
1170 	/* Wait up to 10ms for the character(s) to be sent. */
1171 	do {
1172 		status = serial_in(up, UART_LSR);
1173 
1174 		if (status & UART_LSR_BI)
1175 			up->lsr_break_flag = UART_LSR_BI;
1176 
1177 		if (--tmout == 0)
1178 			break;
1179 		udelay(1);
1180 	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
1181 
1182 	/* Wait up to 1s for flow control if necessary */
1183 	if (up->port.flags & UPF_CONS_FLOW) {
1184 		tmout = 1000000;
1185 		for (tmout = 1000000; tmout; tmout--) {
1186 			unsigned int msr = serial_in(up, UART_MSR);
1187 
1188 			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1189 			if (msr & UART_MSR_CTS)
1190 				break;
1191 
1192 			udelay(1);
1193 		}
1194 	}
1195 }
1196 
1197 #ifdef CONFIG_CONSOLE_POLL
1198 
1199 static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
1200 {
1201 	struct uart_omap_port *up = to_uart_omap_port(port);
1202 
1203 	pm_runtime_get_sync(up->dev);
1204 	wait_for_xmitr(up);
1205 	serial_out(up, UART_TX, ch);
1206 	pm_runtime_mark_last_busy(up->dev);
1207 	pm_runtime_put_autosuspend(up->dev);
1208 }
1209 
1210 static int serial_omap_poll_get_char(struct uart_port *port)
1211 {
1212 	struct uart_omap_port *up = to_uart_omap_port(port);
1213 	unsigned int status;
1214 
1215 	pm_runtime_get_sync(up->dev);
1216 	status = serial_in(up, UART_LSR);
1217 	if (!(status & UART_LSR_DR)) {
1218 		status = NO_POLL_CHAR;
1219 		goto out;
1220 	}
1221 
1222 	status = serial_in(up, UART_RX);
1223 
1224 out:
1225 	pm_runtime_mark_last_busy(up->dev);
1226 	pm_runtime_put_autosuspend(up->dev);
1227 
1228 	return status;
1229 }
1230 
1231 #endif /* CONFIG_CONSOLE_POLL */
1232 
1233 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
1234 
1235 static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
1236 
1237 static struct uart_driver serial_omap_reg;
1238 
1239 static void serial_omap_console_putchar(struct uart_port *port, int ch)
1240 {
1241 	struct uart_omap_port *up = to_uart_omap_port(port);
1242 
1243 	wait_for_xmitr(up);
1244 	serial_out(up, UART_TX, ch);
1245 }
1246 
1247 static void
1248 serial_omap_console_write(struct console *co, const char *s,
1249 		unsigned int count)
1250 {
1251 	struct uart_omap_port *up = serial_omap_console_ports[co->index];
1252 	unsigned long flags;
1253 	unsigned int ier;
1254 	int locked = 1;
1255 
1256 	pm_runtime_get_sync(up->dev);
1257 
1258 	local_irq_save(flags);
1259 	if (up->port.sysrq)
1260 		locked = 0;
1261 	else if (oops_in_progress)
1262 		locked = spin_trylock(&up->port.lock);
1263 	else
1264 		spin_lock(&up->port.lock);
1265 
1266 	/*
1267 	 * First save the IER then disable the interrupts
1268 	 */
1269 	ier = serial_in(up, UART_IER);
1270 	serial_out(up, UART_IER, 0);
1271 
1272 	uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1273 
1274 	/*
1275 	 * Finally, wait for transmitter to become empty
1276 	 * and restore the IER
1277 	 */
1278 	wait_for_xmitr(up);
1279 	serial_out(up, UART_IER, ier);
1280 	/*
1281 	 * The receive handling will happen properly because the
1282 	 * receive ready bit will still be set; it is not cleared
1283 	 * on read.  However, modem control will not, we must
1284 	 * call it if we have saved something in the saved flags
1285 	 * while processing with interrupts off.
1286 	 */
1287 	if (up->msr_saved_flags)
1288 		check_modem_status(up);
1289 
1290 	pm_runtime_mark_last_busy(up->dev);
1291 	pm_runtime_put_autosuspend(up->dev);
1292 	if (locked)
1293 		spin_unlock(&up->port.lock);
1294 	local_irq_restore(flags);
1295 }
1296 
1297 static int __init
1298 serial_omap_console_setup(struct console *co, char *options)
1299 {
1300 	struct uart_omap_port *up;
1301 	int baud = 115200;
1302 	int bits = 8;
1303 	int parity = 'n';
1304 	int flow = 'n';
1305 
1306 	if (serial_omap_console_ports[co->index] == NULL)
1307 		return -ENODEV;
1308 	up = serial_omap_console_ports[co->index];
1309 
1310 	if (options)
1311 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1312 
1313 	return uart_set_options(&up->port, co, baud, parity, bits, flow);
1314 }
1315 
1316 static struct console serial_omap_console = {
1317 	.name		= OMAP_SERIAL_NAME,
1318 	.write		= serial_omap_console_write,
1319 	.device		= uart_console_device,
1320 	.setup		= serial_omap_console_setup,
1321 	.flags		= CON_PRINTBUFFER,
1322 	.index		= -1,
1323 	.data		= &serial_omap_reg,
1324 };
1325 
1326 static void serial_omap_add_console_port(struct uart_omap_port *up)
1327 {
1328 	serial_omap_console_ports[up->port.line] = up;
1329 }
1330 
1331 #define OMAP_CONSOLE	(&serial_omap_console)
1332 
1333 #else
1334 
1335 #define OMAP_CONSOLE	NULL
1336 
1337 static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1338 {}
1339 
1340 #endif
1341 
1342 /* Enable or disable the rs485 support */
1343 static int
1344 serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
1345 {
1346 	struct uart_omap_port *up = to_uart_omap_port(port);
1347 	unsigned int mode;
1348 	int val;
1349 
1350 	pm_runtime_get_sync(up->dev);
1351 
1352 	/* Disable interrupts from this port */
1353 	mode = up->ier;
1354 	up->ier = 0;
1355 	serial_out(up, UART_IER, 0);
1356 
1357 	/* store new config */
1358 	port->rs485 = *rs485conf;
1359 
1360 	/*
1361 	 * Just as a precaution, only allow rs485
1362 	 * to be enabled if the gpio pin is valid
1363 	 */
1364 	if (gpio_is_valid(up->rts_gpio)) {
1365 		/* enable / disable rts */
1366 		val = (port->rs485.flags & SER_RS485_ENABLED) ?
1367 			SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
1368 		val = (port->rs485.flags & val) ? 1 : 0;
1369 		gpio_set_value(up->rts_gpio, val);
1370 	} else
1371 		port->rs485.flags &= ~SER_RS485_ENABLED;
1372 
1373 	/* Enable interrupts */
1374 	up->ier = mode;
1375 	serial_out(up, UART_IER, up->ier);
1376 
1377 	/* If RS-485 is disabled, make sure the THR interrupt is fired when
1378 	 * TX FIFO is below the trigger level.
1379 	 */
1380 	if (!(port->rs485.flags & SER_RS485_ENABLED) &&
1381 	    (up->scr & OMAP_UART_SCR_TX_EMPTY)) {
1382 		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
1383 		serial_out(up, UART_OMAP_SCR, up->scr);
1384 	}
1385 
1386 	pm_runtime_mark_last_busy(up->dev);
1387 	pm_runtime_put_autosuspend(up->dev);
1388 
1389 	return 0;
1390 }
1391 
1392 static struct uart_ops serial_omap_pops = {
1393 	.tx_empty	= serial_omap_tx_empty,
1394 	.set_mctrl	= serial_omap_set_mctrl,
1395 	.get_mctrl	= serial_omap_get_mctrl,
1396 	.stop_tx	= serial_omap_stop_tx,
1397 	.start_tx	= serial_omap_start_tx,
1398 	.throttle	= serial_omap_throttle,
1399 	.unthrottle	= serial_omap_unthrottle,
1400 	.stop_rx	= serial_omap_stop_rx,
1401 	.enable_ms	= serial_omap_enable_ms,
1402 	.break_ctl	= serial_omap_break_ctl,
1403 	.startup	= serial_omap_startup,
1404 	.shutdown	= serial_omap_shutdown,
1405 	.set_termios	= serial_omap_set_termios,
1406 	.pm		= serial_omap_pm,
1407 	.type		= serial_omap_type,
1408 	.release_port	= serial_omap_release_port,
1409 	.request_port	= serial_omap_request_port,
1410 	.config_port	= serial_omap_config_port,
1411 	.verify_port	= serial_omap_verify_port,
1412 #ifdef CONFIG_CONSOLE_POLL
1413 	.poll_put_char  = serial_omap_poll_put_char,
1414 	.poll_get_char  = serial_omap_poll_get_char,
1415 #endif
1416 };
1417 
1418 static struct uart_driver serial_omap_reg = {
1419 	.owner		= THIS_MODULE,
1420 	.driver_name	= "OMAP-SERIAL",
1421 	.dev_name	= OMAP_SERIAL_NAME,
1422 	.nr		= OMAP_MAX_HSUART_PORTS,
1423 	.cons		= OMAP_CONSOLE,
1424 };
1425 
1426 #ifdef CONFIG_PM_SLEEP
1427 static int serial_omap_prepare(struct device *dev)
1428 {
1429 	struct uart_omap_port *up = dev_get_drvdata(dev);
1430 
1431 	up->is_suspending = true;
1432 
1433 	return 0;
1434 }
1435 
1436 static void serial_omap_complete(struct device *dev)
1437 {
1438 	struct uart_omap_port *up = dev_get_drvdata(dev);
1439 
1440 	up->is_suspending = false;
1441 }
1442 
1443 static int serial_omap_suspend(struct device *dev)
1444 {
1445 	struct uart_omap_port *up = dev_get_drvdata(dev);
1446 
1447 	uart_suspend_port(&serial_omap_reg, &up->port);
1448 	flush_work(&up->qos_work);
1449 
1450 	if (device_may_wakeup(dev))
1451 		serial_omap_enable_wakeup(up, true);
1452 	else
1453 		serial_omap_enable_wakeup(up, false);
1454 
1455 	return 0;
1456 }
1457 
1458 static int serial_omap_resume(struct device *dev)
1459 {
1460 	struct uart_omap_port *up = dev_get_drvdata(dev);
1461 
1462 	if (device_may_wakeup(dev))
1463 		serial_omap_enable_wakeup(up, false);
1464 
1465 	uart_resume_port(&serial_omap_reg, &up->port);
1466 
1467 	return 0;
1468 }
1469 #else
1470 #define serial_omap_prepare NULL
1471 #define serial_omap_complete NULL
1472 #endif /* CONFIG_PM_SLEEP */
1473 
1474 static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
1475 {
1476 	u32 mvr, scheme;
1477 	u16 revision, major, minor;
1478 
1479 	mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
1480 
1481 	/* Check revision register scheme */
1482 	scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
1483 
1484 	switch (scheme) {
1485 	case 0: /* Legacy Scheme: OMAP2/3 */
1486 		/* MINOR_REV[0:4], MAJOR_REV[4:7] */
1487 		major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
1488 					OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
1489 		minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
1490 		break;
1491 	case 1:
1492 		/* New Scheme: OMAP4+ */
1493 		/* MINOR_REV[0:5], MAJOR_REV[8:10] */
1494 		major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
1495 					OMAP_UART_MVR_MAJ_SHIFT;
1496 		minor = (mvr & OMAP_UART_MVR_MIN_MASK);
1497 		break;
1498 	default:
1499 		dev_warn(up->dev,
1500 			"Unknown %s revision, defaulting to highest\n",
1501 			up->name);
1502 		/* highest possible revision */
1503 		major = 0xff;
1504 		minor = 0xff;
1505 	}
1506 
1507 	/* normalize revision for the driver */
1508 	revision = UART_BUILD_REVISION(major, minor);
1509 
1510 	switch (revision) {
1511 	case OMAP_UART_REV_46:
1512 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1513 				UART_ERRATA_i291_DMA_FORCEIDLE);
1514 		break;
1515 	case OMAP_UART_REV_52:
1516 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1517 				UART_ERRATA_i291_DMA_FORCEIDLE);
1518 		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1519 		break;
1520 	case OMAP_UART_REV_63:
1521 		up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
1522 		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1523 		break;
1524 	default:
1525 		break;
1526 	}
1527 }
1528 
1529 static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1530 {
1531 	struct omap_uart_port_info *omap_up_info;
1532 
1533 	omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1534 	if (!omap_up_info)
1535 		return NULL; /* out of memory */
1536 
1537 	of_property_read_u32(dev->of_node, "clock-frequency",
1538 					 &omap_up_info->uartclk);
1539 	return omap_up_info;
1540 }
1541 
1542 static int serial_omap_probe_rs485(struct uart_omap_port *up,
1543 				   struct device_node *np)
1544 {
1545 	struct serial_rs485 *rs485conf = &up->port.rs485;
1546 	u32 rs485_delay[2];
1547 	enum of_gpio_flags flags;
1548 	int ret;
1549 
1550 	rs485conf->flags = 0;
1551 	up->rts_gpio = -EINVAL;
1552 
1553 	if (!np)
1554 		return 0;
1555 
1556 	if (of_property_read_bool(np, "rs485-rts-active-high"))
1557 		rs485conf->flags |= SER_RS485_RTS_ON_SEND;
1558 	else
1559 		rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
1560 
1561 	/* check for tx enable gpio */
1562 	up->rts_gpio = of_get_named_gpio_flags(np, "rts-gpio", 0, &flags);
1563 	if (gpio_is_valid(up->rts_gpio)) {
1564 		ret = devm_gpio_request(up->dev, up->rts_gpio, "omap-serial");
1565 		if (ret < 0)
1566 			return ret;
1567 		ret = gpio_direction_output(up->rts_gpio,
1568 					    flags & SER_RS485_RTS_AFTER_SEND);
1569 		if (ret < 0)
1570 			return ret;
1571 	} else if (up->rts_gpio == -EPROBE_DEFER) {
1572 		return -EPROBE_DEFER;
1573 	} else {
1574 		up->rts_gpio = -EINVAL;
1575 	}
1576 
1577 	if (of_property_read_u32_array(np, "rs485-rts-delay",
1578 				    rs485_delay, 2) == 0) {
1579 		rs485conf->delay_rts_before_send = rs485_delay[0];
1580 		rs485conf->delay_rts_after_send = rs485_delay[1];
1581 	}
1582 
1583 	if (of_property_read_bool(np, "rs485-rx-during-tx"))
1584 		rs485conf->flags |= SER_RS485_RX_DURING_TX;
1585 
1586 	if (of_property_read_bool(np, "linux,rs485-enabled-at-boot-time"))
1587 		rs485conf->flags |= SER_RS485_ENABLED;
1588 
1589 	return 0;
1590 }
1591 
1592 static int serial_omap_probe(struct platform_device *pdev)
1593 {
1594 	struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
1595 	struct uart_omap_port *up;
1596 	struct resource *mem;
1597 	void __iomem *base;
1598 	int uartirq = 0;
1599 	int wakeirq = 0;
1600 	int ret;
1601 
1602 	/* The optional wakeirq may be specified in the board dts file */
1603 	if (pdev->dev.of_node) {
1604 		uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0);
1605 		if (!uartirq)
1606 			return -EPROBE_DEFER;
1607 		wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
1608 		omap_up_info = of_get_uart_port_info(&pdev->dev);
1609 		pdev->dev.platform_data = omap_up_info;
1610 	} else {
1611 		uartirq = platform_get_irq(pdev, 0);
1612 		if (uartirq < 0)
1613 			return -EPROBE_DEFER;
1614 	}
1615 
1616 	up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
1617 	if (!up)
1618 		return -ENOMEM;
1619 
1620 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1621 	base = devm_ioremap_resource(&pdev->dev, mem);
1622 	if (IS_ERR(base))
1623 		return PTR_ERR(base);
1624 
1625 	up->dev = &pdev->dev;
1626 	up->port.dev = &pdev->dev;
1627 	up->port.type = PORT_OMAP;
1628 	up->port.iotype = UPIO_MEM;
1629 	up->port.irq = uartirq;
1630 	up->port.regshift = 2;
1631 	up->port.fifosize = 64;
1632 	up->port.ops = &serial_omap_pops;
1633 
1634 	if (pdev->dev.of_node)
1635 		ret = of_alias_get_id(pdev->dev.of_node, "serial");
1636 	else
1637 		ret = pdev->id;
1638 
1639 	if (ret < 0) {
1640 		dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1641 			ret);
1642 		goto err_port_line;
1643 	}
1644 	up->port.line = ret;
1645 
1646 	if (up->port.line >= OMAP_MAX_HSUART_PORTS) {
1647 		dev_err(&pdev->dev, "uart ID %d >  MAX %d.\n", up->port.line,
1648 			OMAP_MAX_HSUART_PORTS);
1649 		ret = -ENXIO;
1650 		goto err_port_line;
1651 	}
1652 
1653 	up->wakeirq = wakeirq;
1654 	if (!up->wakeirq)
1655 		dev_info(up->port.dev, "no wakeirq for uart%d\n",
1656 			 up->port.line);
1657 
1658 	ret = serial_omap_probe_rs485(up, pdev->dev.of_node);
1659 	if (ret < 0)
1660 		goto err_rs485;
1661 
1662 	sprintf(up->name, "OMAP UART%d", up->port.line);
1663 	up->port.mapbase = mem->start;
1664 	up->port.membase = base;
1665 	up->port.flags = omap_up_info->flags;
1666 	up->port.uartclk = omap_up_info->uartclk;
1667 	up->port.rs485_config = serial_omap_config_rs485;
1668 	if (!up->port.uartclk) {
1669 		up->port.uartclk = DEFAULT_CLK_SPEED;
1670 		dev_warn(&pdev->dev,
1671 			 "No clock speed specified: using default: %d\n",
1672 			 DEFAULT_CLK_SPEED);
1673 	}
1674 
1675 	up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1676 	up->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1677 	pm_qos_add_request(&up->pm_qos_request,
1678 		PM_QOS_CPU_DMA_LATENCY, up->latency);
1679 	INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1680 
1681 	platform_set_drvdata(pdev, up);
1682 	if (omap_up_info->autosuspend_timeout == 0)
1683 		omap_up_info->autosuspend_timeout = -1;
1684 
1685 	device_init_wakeup(up->dev, true);
1686 	pm_runtime_use_autosuspend(&pdev->dev);
1687 	pm_runtime_set_autosuspend_delay(&pdev->dev,
1688 			omap_up_info->autosuspend_timeout);
1689 
1690 	pm_runtime_irq_safe(&pdev->dev);
1691 	pm_runtime_enable(&pdev->dev);
1692 
1693 	pm_runtime_get_sync(&pdev->dev);
1694 
1695 	omap_serial_fill_features_erratas(up);
1696 
1697 	ui[up->port.line] = up;
1698 	serial_omap_add_console_port(up);
1699 
1700 	ret = uart_add_one_port(&serial_omap_reg, &up->port);
1701 	if (ret != 0)
1702 		goto err_add_port;
1703 
1704 	pm_runtime_mark_last_busy(up->dev);
1705 	pm_runtime_put_autosuspend(up->dev);
1706 	return 0;
1707 
1708 err_add_port:
1709 	pm_runtime_put(&pdev->dev);
1710 	pm_runtime_disable(&pdev->dev);
1711 	pm_qos_remove_request(&up->pm_qos_request);
1712 	device_init_wakeup(up->dev, false);
1713 err_rs485:
1714 err_port_line:
1715 	return ret;
1716 }
1717 
1718 static int serial_omap_remove(struct platform_device *dev)
1719 {
1720 	struct uart_omap_port *up = platform_get_drvdata(dev);
1721 
1722 	pm_runtime_put_sync(up->dev);
1723 	pm_runtime_disable(up->dev);
1724 	uart_remove_one_port(&serial_omap_reg, &up->port);
1725 	pm_qos_remove_request(&up->pm_qos_request);
1726 	device_init_wakeup(&dev->dev, false);
1727 
1728 	return 0;
1729 }
1730 
1731 /*
1732  * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1733  * The access to uart register after MDR1 Access
1734  * causes UART to corrupt data.
1735  *
1736  * Need a delay =
1737  * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1738  * give 10 times as much
1739  */
1740 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1741 {
1742 	u8 timeout = 255;
1743 
1744 	serial_out(up, UART_OMAP_MDR1, mdr1);
1745 	udelay(2);
1746 	serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1747 			UART_FCR_CLEAR_RCVR);
1748 	/*
1749 	 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1750 	 * TX_FIFO_E bit is 1.
1751 	 */
1752 	while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1753 				(UART_LSR_THRE | UART_LSR_DR))) {
1754 		timeout--;
1755 		if (!timeout) {
1756 			/* Should *never* happen. we warn and carry on */
1757 			dev_crit(up->dev, "Errata i202: timedout %x\n",
1758 						serial_in(up, UART_LSR));
1759 			break;
1760 		}
1761 		udelay(1);
1762 	}
1763 }
1764 
1765 #ifdef CONFIG_PM
1766 static void serial_omap_restore_context(struct uart_omap_port *up)
1767 {
1768 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1769 		serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1770 	else
1771 		serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1772 
1773 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1774 	serial_out(up, UART_EFR, UART_EFR_ECB);
1775 	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1776 	serial_out(up, UART_IER, 0x0);
1777 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1778 	serial_out(up, UART_DLL, up->dll);
1779 	serial_out(up, UART_DLM, up->dlh);
1780 	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1781 	serial_out(up, UART_IER, up->ier);
1782 	serial_out(up, UART_FCR, up->fcr);
1783 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1784 	serial_out(up, UART_MCR, up->mcr);
1785 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1786 	serial_out(up, UART_OMAP_SCR, up->scr);
1787 	serial_out(up, UART_EFR, up->efr);
1788 	serial_out(up, UART_LCR, up->lcr);
1789 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1790 		serial_omap_mdr1_errataset(up, up->mdr1);
1791 	else
1792 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1793 	serial_out(up, UART_OMAP_WER, up->wer);
1794 }
1795 
1796 static int serial_omap_runtime_suspend(struct device *dev)
1797 {
1798 	struct uart_omap_port *up = dev_get_drvdata(dev);
1799 
1800 	if (!up)
1801 		return -EINVAL;
1802 
1803 	/*
1804 	* When using 'no_console_suspend', the console UART must not be
1805 	* suspended. Since driver suspend is managed by runtime suspend,
1806 	* preventing runtime suspend (by returning error) will keep device
1807 	* active during suspend.
1808 	*/
1809 	if (up->is_suspending && !console_suspend_enabled &&
1810 	    uart_console(&up->port))
1811 		return -EBUSY;
1812 
1813 	up->context_loss_cnt = serial_omap_get_context_loss_count(up);
1814 
1815 	serial_omap_enable_wakeup(up, true);
1816 
1817 	up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1818 	schedule_work(&up->qos_work);
1819 
1820 	return 0;
1821 }
1822 
1823 static int serial_omap_runtime_resume(struct device *dev)
1824 {
1825 	struct uart_omap_port *up = dev_get_drvdata(dev);
1826 
1827 	int loss_cnt = serial_omap_get_context_loss_count(up);
1828 
1829 	serial_omap_enable_wakeup(up, false);
1830 
1831 	if (loss_cnt < 0) {
1832 		dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
1833 			loss_cnt);
1834 		serial_omap_restore_context(up);
1835 	} else if (up->context_loss_cnt != loss_cnt) {
1836 		serial_omap_restore_context(up);
1837 	}
1838 	up->latency = up->calc_latency;
1839 	schedule_work(&up->qos_work);
1840 
1841 	return 0;
1842 }
1843 #endif
1844 
1845 static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1846 	SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1847 	SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1848 				serial_omap_runtime_resume, NULL)
1849 	.prepare        = serial_omap_prepare,
1850 	.complete       = serial_omap_complete,
1851 };
1852 
1853 #if defined(CONFIG_OF)
1854 static const struct of_device_id omap_serial_of_match[] = {
1855 	{ .compatible = "ti,omap2-uart" },
1856 	{ .compatible = "ti,omap3-uart" },
1857 	{ .compatible = "ti,omap4-uart" },
1858 	{},
1859 };
1860 MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1861 #endif
1862 
1863 static struct platform_driver serial_omap_driver = {
1864 	.probe          = serial_omap_probe,
1865 	.remove         = serial_omap_remove,
1866 	.driver		= {
1867 		.name	= DRIVER_NAME,
1868 		.pm	= &serial_omap_dev_pm_ops,
1869 		.of_match_table = of_match_ptr(omap_serial_of_match),
1870 	},
1871 };
1872 
1873 static int __init serial_omap_init(void)
1874 {
1875 	int ret;
1876 
1877 	ret = uart_register_driver(&serial_omap_reg);
1878 	if (ret != 0)
1879 		return ret;
1880 	ret = platform_driver_register(&serial_omap_driver);
1881 	if (ret != 0)
1882 		uart_unregister_driver(&serial_omap_reg);
1883 	return ret;
1884 }
1885 
1886 static void __exit serial_omap_exit(void)
1887 {
1888 	platform_driver_unregister(&serial_omap_driver);
1889 	uart_unregister_driver(&serial_omap_reg);
1890 }
1891 
1892 module_init(serial_omap_init);
1893 module_exit(serial_omap_exit);
1894 
1895 MODULE_DESCRIPTION("OMAP High Speed UART driver");
1896 MODULE_LICENSE("GPL");
1897 MODULE_AUTHOR("Texas Instruments Inc");
1898