xref: /linux/drivers/tty/serial/omap-serial.c (revision f1615bbe9be4def59c3b3eaddb60722efeed16c2)
1 /*
2  * Driver for OMAP-UART controller.
3  * Based on drivers/serial/8250.c
4  *
5  * Copyright (C) 2010 Texas Instruments.
6  *
7  * Authors:
8  *	Govindraj R	<govindraj.raja@ti.com>
9  *	Thara Gopinath	<thara@ti.com>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  *
16  * Note: This driver is made separate from 8250 driver as we cannot
17  * over load 8250 driver with omap platform specific configuration for
18  * features like DMA, it makes easier to implement features like DMA and
19  * hardware flow control and software flow control configuration with
20  * this driver as required for the omap-platform.
21  */
22 
23 #if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
24 #define SUPPORT_SYSRQ
25 #endif
26 
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/console.h>
30 #include <linux/serial_reg.h>
31 #include <linux/delay.h>
32 #include <linux/slab.h>
33 #include <linux/tty.h>
34 #include <linux/tty_flip.h>
35 #include <linux/platform_device.h>
36 #include <linux/io.h>
37 #include <linux/clk.h>
38 #include <linux/serial_core.h>
39 #include <linux/irq.h>
40 #include <linux/pm_runtime.h>
41 #include <linux/of.h>
42 #include <linux/of_irq.h>
43 #include <linux/gpio.h>
44 #include <linux/of_gpio.h>
45 #include <linux/platform_data/serial-omap.h>
46 
47 #include <dt-bindings/gpio/gpio.h>
48 
49 #define OMAP_MAX_HSUART_PORTS	6
50 
51 #define UART_BUILD_REVISION(x, y)	(((x) << 8) | (y))
52 
53 #define OMAP_UART_REV_42 0x0402
54 #define OMAP_UART_REV_46 0x0406
55 #define OMAP_UART_REV_52 0x0502
56 #define OMAP_UART_REV_63 0x0603
57 
58 #define OMAP_UART_TX_WAKEUP_EN		BIT(7)
59 
60 /* Feature flags */
61 #define OMAP_UART_WER_HAS_TX_WAKEUP	BIT(0)
62 
63 #define UART_ERRATA_i202_MDR1_ACCESS	BIT(0)
64 #define UART_ERRATA_i291_DMA_FORCEIDLE	BIT(1)
65 
66 #define DEFAULT_CLK_SPEED 48000000 /* 48Mhz*/
67 
68 /* SCR register bitmasks */
69 #define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK		(1 << 7)
70 #define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK		(1 << 6)
71 #define OMAP_UART_SCR_TX_EMPTY			(1 << 3)
72 
73 /* FCR register bitmasks */
74 #define OMAP_UART_FCR_RX_FIFO_TRIG_MASK			(0x3 << 6)
75 #define OMAP_UART_FCR_TX_FIFO_TRIG_MASK			(0x3 << 4)
76 
77 /* MVR register bitmasks */
78 #define OMAP_UART_MVR_SCHEME_SHIFT	30
79 
80 #define OMAP_UART_LEGACY_MVR_MAJ_MASK	0xf0
81 #define OMAP_UART_LEGACY_MVR_MAJ_SHIFT	4
82 #define OMAP_UART_LEGACY_MVR_MIN_MASK	0x0f
83 
84 #define OMAP_UART_MVR_MAJ_MASK		0x700
85 #define OMAP_UART_MVR_MAJ_SHIFT		8
86 #define OMAP_UART_MVR_MIN_MASK		0x3f
87 
88 #define OMAP_UART_DMA_CH_FREE	-1
89 
90 #define MSR_SAVE_FLAGS		UART_MSR_ANY_DELTA
91 #define OMAP_MODE13X_SPEED	230400
92 
93 /* WER = 0x7F
94  * Enable module level wakeup in WER reg
95  */
96 #define OMAP_UART_WER_MOD_WKUP	0X7F
97 
98 /* Enable XON/XOFF flow control on output */
99 #define OMAP_UART_SW_TX		0x08
100 
101 /* Enable XON/XOFF flow control on input */
102 #define OMAP_UART_SW_RX		0x02
103 
104 #define OMAP_UART_SW_CLR	0xF0
105 
106 #define OMAP_UART_TCR_TRIG	0x0F
107 
108 struct uart_omap_dma {
109 	u8			uart_dma_tx;
110 	u8			uart_dma_rx;
111 	int			rx_dma_channel;
112 	int			tx_dma_channel;
113 	dma_addr_t		rx_buf_dma_phys;
114 	dma_addr_t		tx_buf_dma_phys;
115 	unsigned int		uart_base;
116 	/*
117 	 * Buffer for rx dma.It is not required for tx because the buffer
118 	 * comes from port structure.
119 	 */
120 	unsigned char		*rx_buf;
121 	unsigned int		prev_rx_dma_pos;
122 	int			tx_buf_size;
123 	int			tx_dma_used;
124 	int			rx_dma_used;
125 	spinlock_t		tx_lock;
126 	spinlock_t		rx_lock;
127 	/* timer to poll activity on rx dma */
128 	struct timer_list	rx_timer;
129 	unsigned int		rx_buf_size;
130 	unsigned int		rx_poll_rate;
131 	unsigned int		rx_timeout;
132 };
133 
134 struct uart_omap_port {
135 	struct uart_port	port;
136 	struct uart_omap_dma	uart_dma;
137 	struct device		*dev;
138 	int			wakeirq;
139 
140 	unsigned char		ier;
141 	unsigned char		lcr;
142 	unsigned char		mcr;
143 	unsigned char		fcr;
144 	unsigned char		efr;
145 	unsigned char		dll;
146 	unsigned char		dlh;
147 	unsigned char		mdr1;
148 	unsigned char		scr;
149 	unsigned char		wer;
150 
151 	int			use_dma;
152 	/*
153 	 * Some bits in registers are cleared on a read, so they must
154 	 * be saved whenever the register is read but the bits will not
155 	 * be immediately processed.
156 	 */
157 	unsigned int		lsr_break_flag;
158 	unsigned char		msr_saved_flags;
159 	char			name[20];
160 	unsigned long		port_activity;
161 	int			context_loss_cnt;
162 	u32			errata;
163 	u8			wakeups_enabled;
164 	u32			features;
165 
166 	struct serial_rs485	rs485;
167 	int			rts_gpio;
168 
169 	struct pm_qos_request	pm_qos_request;
170 	u32			latency;
171 	u32			calc_latency;
172 	struct work_struct	qos_work;
173 	bool			is_suspending;
174 };
175 
176 #define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
177 
178 static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
179 
180 /* Forward declaration of functions */
181 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
182 
183 static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
184 {
185 	offset <<= up->port.regshift;
186 	return readw(up->port.membase + offset);
187 }
188 
189 static inline void serial_out(struct uart_omap_port *up, int offset, int value)
190 {
191 	offset <<= up->port.regshift;
192 	writew(value, up->port.membase + offset);
193 }
194 
195 static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
196 {
197 	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
198 	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
199 		       UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
200 	serial_out(up, UART_FCR, 0);
201 }
202 
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 static inline void serial_omap_enable_wakeirq(struct uart_omap_port *up,
214 				       bool enable)
215 {
216 	if (!up->wakeirq)
217 		return;
218 
219 	if (enable)
220 		enable_irq(up->wakeirq);
221 	else
222 		disable_irq_nosync(up->wakeirq);
223 }
224 
225 static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
226 {
227 	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
228 
229 	if (enable == up->wakeups_enabled)
230 		return;
231 
232 	serial_omap_enable_wakeirq(up, enable);
233 	up->wakeups_enabled = enable;
234 
235 	if (!pdata || !pdata->enable_wakeup)
236 		return;
237 
238 	pdata->enable_wakeup(up->dev, enable);
239 }
240 
241 /*
242  * serial_omap_baud_is_mode16 - check if baud rate is MODE16X
243  * @port: uart port info
244  * @baud: baudrate for which mode needs to be determined
245  *
246  * Returns true if baud rate is MODE16X and false if MODE13X
247  * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
248  * and Error Rates" determines modes not for all common baud rates.
249  * E.g. for 1000000 baud rate mode must be 16x, but according to that
250  * table it's determined as 13x.
251  */
252 static bool
253 serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
254 {
255 	unsigned int n13 = port->uartclk / (13 * baud);
256 	unsigned int n16 = port->uartclk / (16 * baud);
257 	int baudAbsDiff13 = baud - (port->uartclk / (13 * n13));
258 	int baudAbsDiff16 = baud - (port->uartclk / (16 * n16));
259 	if (baudAbsDiff13 < 0)
260 		baudAbsDiff13 = -baudAbsDiff13;
261 	if (baudAbsDiff16 < 0)
262 		baudAbsDiff16 = -baudAbsDiff16;
263 
264 	return (baudAbsDiff13 >= baudAbsDiff16);
265 }
266 
267 /*
268  * serial_omap_get_divisor - calculate divisor value
269  * @port: uart port info
270  * @baud: baudrate for which divisor needs to be calculated.
271  */
272 static unsigned int
273 serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
274 {
275 	unsigned int mode;
276 
277 	if (!serial_omap_baud_is_mode16(port, baud))
278 		mode = 13;
279 	else
280 		mode = 16;
281 	return port->uartclk/(mode * baud);
282 }
283 
284 static void serial_omap_enable_ms(struct uart_port *port)
285 {
286 	struct uart_omap_port *up = to_uart_omap_port(port);
287 
288 	dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
289 
290 	pm_runtime_get_sync(up->dev);
291 	up->ier |= UART_IER_MSI;
292 	serial_out(up, UART_IER, up->ier);
293 	pm_runtime_mark_last_busy(up->dev);
294 	pm_runtime_put_autosuspend(up->dev);
295 }
296 
297 static void serial_omap_stop_tx(struct uart_port *port)
298 {
299 	struct uart_omap_port *up = to_uart_omap_port(port);
300 	int res;
301 
302 	pm_runtime_get_sync(up->dev);
303 
304 	/* Handle RS-485 */
305 	if (up->rs485.flags & SER_RS485_ENABLED) {
306 		if (up->scr & OMAP_UART_SCR_TX_EMPTY) {
307 			/* THR interrupt is fired when both TX FIFO and TX
308 			 * shift register are empty. This means there's nothing
309 			 * left to transmit now, so make sure the THR interrupt
310 			 * is fired when TX FIFO is below the trigger level,
311 			 * disable THR interrupts and toggle the RS-485 GPIO
312 			 * data direction pin if needed.
313 			 */
314 			up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
315 			serial_out(up, UART_OMAP_SCR, up->scr);
316 			res = (up->rs485.flags & SER_RS485_RTS_AFTER_SEND) ? 1 : 0;
317 			if (gpio_get_value(up->rts_gpio) != res) {
318 				if (up->rs485.delay_rts_after_send > 0)
319 					mdelay(up->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 ((up->rs485.flags & SER_RS485_ENABLED) &&
343 	    !(up->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 (up->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 = (up->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 (up->rs485.delay_rts_before_send > 0)
428 				mdelay(up->rs485.delay_rts_before_send);
429 		}
430 	}
431 
432 	if ((up->rs485.flags & SER_RS485_ENABLED) &&
433 	    !(up->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;
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 	pm_runtime_mark_last_busy(up->dev);
690 	pm_runtime_put_autosuspend(up->dev);
691 }
692 
693 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
694 {
695 	struct uart_omap_port *up = to_uart_omap_port(port);
696 	unsigned long flags = 0;
697 
698 	dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
699 	pm_runtime_get_sync(up->dev);
700 	spin_lock_irqsave(&up->port.lock, flags);
701 	if (break_state == -1)
702 		up->lcr |= UART_LCR_SBC;
703 	else
704 		up->lcr &= ~UART_LCR_SBC;
705 	serial_out(up, UART_LCR, up->lcr);
706 	spin_unlock_irqrestore(&up->port.lock, flags);
707 	pm_runtime_mark_last_busy(up->dev);
708 	pm_runtime_put_autosuspend(up->dev);
709 }
710 
711 static int serial_omap_startup(struct uart_port *port)
712 {
713 	struct uart_omap_port *up = to_uart_omap_port(port);
714 	unsigned long flags = 0;
715 	int retval;
716 
717 	/*
718 	 * Allocate the IRQ
719 	 */
720 	retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
721 				up->name, up);
722 	if (retval)
723 		return retval;
724 
725 	/* Optional wake-up IRQ */
726 	if (up->wakeirq) {
727 		retval = request_irq(up->wakeirq, serial_omap_irq,
728 				     up->port.irqflags, up->name, up);
729 		if (retval) {
730 			free_irq(up->port.irq, up);
731 			return retval;
732 		}
733 		disable_irq(up->wakeirq);
734 	}
735 
736 	dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
737 
738 	pm_runtime_get_sync(up->dev);
739 	/*
740 	 * Clear the FIFO buffers and disable them.
741 	 * (they will be reenabled in set_termios())
742 	 */
743 	serial_omap_clear_fifos(up);
744 	/* For Hardware flow control */
745 	serial_out(up, UART_MCR, UART_MCR_RTS);
746 
747 	/*
748 	 * Clear the interrupt registers.
749 	 */
750 	(void) serial_in(up, UART_LSR);
751 	if (serial_in(up, UART_LSR) & UART_LSR_DR)
752 		(void) serial_in(up, UART_RX);
753 	(void) serial_in(up, UART_IIR);
754 	(void) serial_in(up, UART_MSR);
755 
756 	/*
757 	 * Now, initialize the UART
758 	 */
759 	serial_out(up, UART_LCR, UART_LCR_WLEN8);
760 	spin_lock_irqsave(&up->port.lock, flags);
761 	/*
762 	 * Most PC uarts need OUT2 raised to enable interrupts.
763 	 */
764 	up->port.mctrl |= TIOCM_OUT2;
765 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
766 	spin_unlock_irqrestore(&up->port.lock, flags);
767 
768 	up->msr_saved_flags = 0;
769 	/*
770 	 * Finally, enable interrupts. Note: Modem status interrupts
771 	 * are set via set_termios(), which will be occurring imminently
772 	 * anyway, so we don't enable them here.
773 	 */
774 	up->ier = UART_IER_RLSI | UART_IER_RDI;
775 	serial_out(up, UART_IER, up->ier);
776 
777 	/* Enable module level wake up */
778 	up->wer = OMAP_UART_WER_MOD_WKUP;
779 	if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
780 		up->wer |= OMAP_UART_TX_WAKEUP_EN;
781 
782 	serial_out(up, UART_OMAP_WER, up->wer);
783 
784 	pm_runtime_mark_last_busy(up->dev);
785 	pm_runtime_put_autosuspend(up->dev);
786 	up->port_activity = jiffies;
787 	return 0;
788 }
789 
790 static void serial_omap_shutdown(struct uart_port *port)
791 {
792 	struct uart_omap_port *up = to_uart_omap_port(port);
793 	unsigned long flags = 0;
794 
795 	dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
796 
797 	pm_runtime_get_sync(up->dev);
798 	/*
799 	 * Disable interrupts from this port
800 	 */
801 	up->ier = 0;
802 	serial_out(up, UART_IER, 0);
803 
804 	spin_lock_irqsave(&up->port.lock, flags);
805 	up->port.mctrl &= ~TIOCM_OUT2;
806 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
807 	spin_unlock_irqrestore(&up->port.lock, flags);
808 
809 	/*
810 	 * Disable break condition and FIFOs
811 	 */
812 	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
813 	serial_omap_clear_fifos(up);
814 
815 	/*
816 	 * Read data port to reset things, and then free the irq
817 	 */
818 	if (serial_in(up, UART_LSR) & UART_LSR_DR)
819 		(void) serial_in(up, UART_RX);
820 
821 	pm_runtime_mark_last_busy(up->dev);
822 	pm_runtime_put_autosuspend(up->dev);
823 	free_irq(up->port.irq, up);
824 	if (up->wakeirq)
825 		free_irq(up->wakeirq, up);
826 }
827 
828 static void serial_omap_uart_qos_work(struct work_struct *work)
829 {
830 	struct uart_omap_port *up = container_of(work, struct uart_omap_port,
831 						qos_work);
832 
833 	pm_qos_update_request(&up->pm_qos_request, up->latency);
834 }
835 
836 static void
837 serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
838 			struct ktermios *old)
839 {
840 	struct uart_omap_port *up = to_uart_omap_port(port);
841 	unsigned char cval = 0;
842 	unsigned long flags = 0;
843 	unsigned int baud, quot;
844 
845 	switch (termios->c_cflag & CSIZE) {
846 	case CS5:
847 		cval = UART_LCR_WLEN5;
848 		break;
849 	case CS6:
850 		cval = UART_LCR_WLEN6;
851 		break;
852 	case CS7:
853 		cval = UART_LCR_WLEN7;
854 		break;
855 	default:
856 	case CS8:
857 		cval = UART_LCR_WLEN8;
858 		break;
859 	}
860 
861 	if (termios->c_cflag & CSTOPB)
862 		cval |= UART_LCR_STOP;
863 	if (termios->c_cflag & PARENB)
864 		cval |= UART_LCR_PARITY;
865 	if (!(termios->c_cflag & PARODD))
866 		cval |= UART_LCR_EPAR;
867 	if (termios->c_cflag & CMSPAR)
868 		cval |= UART_LCR_SPAR;
869 
870 	/*
871 	 * Ask the core to calculate the divisor for us.
872 	 */
873 
874 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
875 	quot = serial_omap_get_divisor(port, baud);
876 
877 	/* calculate wakeup latency constraint */
878 	up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
879 	up->latency = up->calc_latency;
880 	schedule_work(&up->qos_work);
881 
882 	up->dll = quot & 0xff;
883 	up->dlh = quot >> 8;
884 	up->mdr1 = UART_OMAP_MDR1_DISABLE;
885 
886 	up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
887 			UART_FCR_ENABLE_FIFO;
888 
889 	/*
890 	 * Ok, we're now changing the port state. Do it with
891 	 * interrupts disabled.
892 	 */
893 	pm_runtime_get_sync(up->dev);
894 	spin_lock_irqsave(&up->port.lock, flags);
895 
896 	/*
897 	 * Update the per-port timeout.
898 	 */
899 	uart_update_timeout(port, termios->c_cflag, baud);
900 
901 	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
902 	if (termios->c_iflag & INPCK)
903 		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
904 	if (termios->c_iflag & (BRKINT | PARMRK))
905 		up->port.read_status_mask |= UART_LSR_BI;
906 
907 	/*
908 	 * Characters to ignore
909 	 */
910 	up->port.ignore_status_mask = 0;
911 	if (termios->c_iflag & IGNPAR)
912 		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
913 	if (termios->c_iflag & IGNBRK) {
914 		up->port.ignore_status_mask |= UART_LSR_BI;
915 		/*
916 		 * If we're ignoring parity and break indicators,
917 		 * ignore overruns too (for real raw support).
918 		 */
919 		if (termios->c_iflag & IGNPAR)
920 			up->port.ignore_status_mask |= UART_LSR_OE;
921 	}
922 
923 	/*
924 	 * ignore all characters if CREAD is not set
925 	 */
926 	if ((termios->c_cflag & CREAD) == 0)
927 		up->port.ignore_status_mask |= UART_LSR_DR;
928 
929 	/*
930 	 * Modem status interrupts
931 	 */
932 	up->ier &= ~UART_IER_MSI;
933 	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
934 		up->ier |= UART_IER_MSI;
935 	serial_out(up, UART_IER, up->ier);
936 	serial_out(up, UART_LCR, cval);		/* reset DLAB */
937 	up->lcr = cval;
938 	up->scr = 0;
939 
940 	/* FIFOs and DMA Settings */
941 
942 	/* FCR can be changed only when the
943 	 * baud clock is not running
944 	 * DLL_REG and DLH_REG set to 0.
945 	 */
946 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
947 	serial_out(up, UART_DLL, 0);
948 	serial_out(up, UART_DLM, 0);
949 	serial_out(up, UART_LCR, 0);
950 
951 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
952 
953 	up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
954 	up->efr &= ~UART_EFR_SCD;
955 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
956 
957 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
958 	up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
959 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
960 	/* FIFO ENABLE, DMA MODE */
961 
962 	up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
963 	/*
964 	 * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
965 	 * sets Enables the granularity of 1 for TRIGGER RX
966 	 * level. Along with setting RX FIFO trigger level
967 	 * to 1 (as noted below, 16 characters) and TLR[3:0]
968 	 * to zero this will result RX FIFO threshold level
969 	 * to 1 character, instead of 16 as noted in comment
970 	 * below.
971 	 */
972 
973 	/* Set receive FIFO threshold to 16 characters and
974 	 * transmit FIFO threshold to 32 spaces
975 	 */
976 	up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
977 	up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
978 	up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
979 		UART_FCR_ENABLE_FIFO;
980 
981 	serial_out(up, UART_FCR, up->fcr);
982 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
983 
984 	serial_out(up, UART_OMAP_SCR, up->scr);
985 
986 	/* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
987 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
988 	serial_out(up, UART_MCR, up->mcr);
989 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
990 	serial_out(up, UART_EFR, up->efr);
991 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
992 
993 	/* Protocol, Baud Rate, and Interrupt Settings */
994 
995 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
996 		serial_omap_mdr1_errataset(up, up->mdr1);
997 	else
998 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
999 
1000 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1001 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1002 
1003 	serial_out(up, UART_LCR, 0);
1004 	serial_out(up, UART_IER, 0);
1005 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1006 
1007 	serial_out(up, UART_DLL, up->dll);	/* LS of divisor */
1008 	serial_out(up, UART_DLM, up->dlh);	/* MS of divisor */
1009 
1010 	serial_out(up, UART_LCR, 0);
1011 	serial_out(up, UART_IER, up->ier);
1012 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1013 
1014 	serial_out(up, UART_EFR, up->efr);
1015 	serial_out(up, UART_LCR, cval);
1016 
1017 	if (!serial_omap_baud_is_mode16(port, baud))
1018 		up->mdr1 = UART_OMAP_MDR1_13X_MODE;
1019 	else
1020 		up->mdr1 = UART_OMAP_MDR1_16X_MODE;
1021 
1022 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1023 		serial_omap_mdr1_errataset(up, up->mdr1);
1024 	else
1025 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1026 
1027 	/* Configure flow control */
1028 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1029 
1030 	/* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
1031 	serial_out(up, UART_XON1, termios->c_cc[VSTART]);
1032 	serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
1033 
1034 	/* Enable access to TCR/TLR */
1035 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1036 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1037 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
1038 
1039 	serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
1040 
1041 	if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
1042 		/* Enable AUTORTS and AUTOCTS */
1043 		up->efr |= UART_EFR_CTS | UART_EFR_RTS;
1044 
1045 		/* Ensure MCR RTS is asserted */
1046 		up->mcr |= UART_MCR_RTS;
1047 	} else {
1048 		/* Disable AUTORTS and AUTOCTS */
1049 		up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
1050 	}
1051 
1052 	if (up->port.flags & UPF_SOFT_FLOW) {
1053 		/* clear SW control mode bits */
1054 		up->efr &= OMAP_UART_SW_CLR;
1055 
1056 		/*
1057 		 * IXON Flag:
1058 		 * Enable XON/XOFF flow control on input.
1059 		 * Receiver compares XON1, XOFF1.
1060 		 */
1061 		if (termios->c_iflag & IXON)
1062 			up->efr |= OMAP_UART_SW_RX;
1063 
1064 		/*
1065 		 * IXOFF Flag:
1066 		 * Enable XON/XOFF flow control on output.
1067 		 * Transmit XON1, XOFF1
1068 		 */
1069 		if (termios->c_iflag & IXOFF)
1070 			up->efr |= OMAP_UART_SW_TX;
1071 
1072 		/*
1073 		 * IXANY Flag:
1074 		 * Enable any character to restart output.
1075 		 * Operation resumes after receiving any
1076 		 * character after recognition of the XOFF character
1077 		 */
1078 		if (termios->c_iflag & IXANY)
1079 			up->mcr |= UART_MCR_XONANY;
1080 		else
1081 			up->mcr &= ~UART_MCR_XONANY;
1082 	}
1083 	serial_out(up, UART_MCR, up->mcr);
1084 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1085 	serial_out(up, UART_EFR, up->efr);
1086 	serial_out(up, UART_LCR, up->lcr);
1087 
1088 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
1089 
1090 	spin_unlock_irqrestore(&up->port.lock, flags);
1091 	pm_runtime_mark_last_busy(up->dev);
1092 	pm_runtime_put_autosuspend(up->dev);
1093 	dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
1094 }
1095 
1096 static void
1097 serial_omap_pm(struct uart_port *port, unsigned int state,
1098 	       unsigned int oldstate)
1099 {
1100 	struct uart_omap_port *up = to_uart_omap_port(port);
1101 	unsigned char efr;
1102 
1103 	dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
1104 
1105 	pm_runtime_get_sync(up->dev);
1106 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1107 	efr = serial_in(up, UART_EFR);
1108 	serial_out(up, UART_EFR, efr | UART_EFR_ECB);
1109 	serial_out(up, UART_LCR, 0);
1110 
1111 	serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
1112 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1113 	serial_out(up, UART_EFR, efr);
1114 	serial_out(up, UART_LCR, 0);
1115 
1116 	if (!device_may_wakeup(up->dev)) {
1117 		if (!state)
1118 			pm_runtime_forbid(up->dev);
1119 		else
1120 			pm_runtime_allow(up->dev);
1121 	}
1122 
1123 	pm_runtime_mark_last_busy(up->dev);
1124 	pm_runtime_put_autosuspend(up->dev);
1125 }
1126 
1127 static void serial_omap_release_port(struct uart_port *port)
1128 {
1129 	dev_dbg(port->dev, "serial_omap_release_port+\n");
1130 }
1131 
1132 static int serial_omap_request_port(struct uart_port *port)
1133 {
1134 	dev_dbg(port->dev, "serial_omap_request_port+\n");
1135 	return 0;
1136 }
1137 
1138 static void serial_omap_config_port(struct uart_port *port, int flags)
1139 {
1140 	struct uart_omap_port *up = to_uart_omap_port(port);
1141 
1142 	dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
1143 							up->port.line);
1144 	up->port.type = PORT_OMAP;
1145 	up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
1146 }
1147 
1148 static int
1149 serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
1150 {
1151 	/* we don't want the core code to modify any port params */
1152 	dev_dbg(port->dev, "serial_omap_verify_port+\n");
1153 	return -EINVAL;
1154 }
1155 
1156 static const char *
1157 serial_omap_type(struct uart_port *port)
1158 {
1159 	struct uart_omap_port *up = to_uart_omap_port(port);
1160 
1161 	dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
1162 	return up->name;
1163 }
1164 
1165 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1166 
1167 static inline void wait_for_xmitr(struct uart_omap_port *up)
1168 {
1169 	unsigned int status, tmout = 10000;
1170 
1171 	/* Wait up to 10ms for the character(s) to be sent. */
1172 	do {
1173 		status = serial_in(up, UART_LSR);
1174 
1175 		if (status & UART_LSR_BI)
1176 			up->lsr_break_flag = UART_LSR_BI;
1177 
1178 		if (--tmout == 0)
1179 			break;
1180 		udelay(1);
1181 	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
1182 
1183 	/* Wait up to 1s for flow control if necessary */
1184 	if (up->port.flags & UPF_CONS_FLOW) {
1185 		tmout = 1000000;
1186 		for (tmout = 1000000; tmout; tmout--) {
1187 			unsigned int msr = serial_in(up, UART_MSR);
1188 
1189 			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1190 			if (msr & UART_MSR_CTS)
1191 				break;
1192 
1193 			udelay(1);
1194 		}
1195 	}
1196 }
1197 
1198 #ifdef CONFIG_CONSOLE_POLL
1199 
1200 static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
1201 {
1202 	struct uart_omap_port *up = to_uart_omap_port(port);
1203 
1204 	pm_runtime_get_sync(up->dev);
1205 	wait_for_xmitr(up);
1206 	serial_out(up, UART_TX, ch);
1207 	pm_runtime_mark_last_busy(up->dev);
1208 	pm_runtime_put_autosuspend(up->dev);
1209 }
1210 
1211 static int serial_omap_poll_get_char(struct uart_port *port)
1212 {
1213 	struct uart_omap_port *up = to_uart_omap_port(port);
1214 	unsigned int status;
1215 
1216 	pm_runtime_get_sync(up->dev);
1217 	status = serial_in(up, UART_LSR);
1218 	if (!(status & UART_LSR_DR)) {
1219 		status = NO_POLL_CHAR;
1220 		goto out;
1221 	}
1222 
1223 	status = serial_in(up, UART_RX);
1224 
1225 out:
1226 	pm_runtime_mark_last_busy(up->dev);
1227 	pm_runtime_put_autosuspend(up->dev);
1228 
1229 	return status;
1230 }
1231 
1232 #endif /* CONFIG_CONSOLE_POLL */
1233 
1234 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
1235 
1236 static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
1237 
1238 static struct uart_driver serial_omap_reg;
1239 
1240 static void serial_omap_console_putchar(struct uart_port *port, int ch)
1241 {
1242 	struct uart_omap_port *up = to_uart_omap_port(port);
1243 
1244 	wait_for_xmitr(up);
1245 	serial_out(up, UART_TX, ch);
1246 }
1247 
1248 static void
1249 serial_omap_console_write(struct console *co, const char *s,
1250 		unsigned int count)
1251 {
1252 	struct uart_omap_port *up = serial_omap_console_ports[co->index];
1253 	unsigned long flags;
1254 	unsigned int ier;
1255 	int locked = 1;
1256 
1257 	pm_runtime_get_sync(up->dev);
1258 
1259 	local_irq_save(flags);
1260 	if (up->port.sysrq)
1261 		locked = 0;
1262 	else if (oops_in_progress)
1263 		locked = spin_trylock(&up->port.lock);
1264 	else
1265 		spin_lock(&up->port.lock);
1266 
1267 	/*
1268 	 * First save the IER then disable the interrupts
1269 	 */
1270 	ier = serial_in(up, UART_IER);
1271 	serial_out(up, UART_IER, 0);
1272 
1273 	uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1274 
1275 	/*
1276 	 * Finally, wait for transmitter to become empty
1277 	 * and restore the IER
1278 	 */
1279 	wait_for_xmitr(up);
1280 	serial_out(up, UART_IER, ier);
1281 	/*
1282 	 * The receive handling will happen properly because the
1283 	 * receive ready bit will still be set; it is not cleared
1284 	 * on read.  However, modem control will not, we must
1285 	 * call it if we have saved something in the saved flags
1286 	 * while processing with interrupts off.
1287 	 */
1288 	if (up->msr_saved_flags)
1289 		check_modem_status(up);
1290 
1291 	pm_runtime_mark_last_busy(up->dev);
1292 	pm_runtime_put_autosuspend(up->dev);
1293 	if (locked)
1294 		spin_unlock(&up->port.lock);
1295 	local_irq_restore(flags);
1296 }
1297 
1298 static int __init
1299 serial_omap_console_setup(struct console *co, char *options)
1300 {
1301 	struct uart_omap_port *up;
1302 	int baud = 115200;
1303 	int bits = 8;
1304 	int parity = 'n';
1305 	int flow = 'n';
1306 
1307 	if (serial_omap_console_ports[co->index] == NULL)
1308 		return -ENODEV;
1309 	up = serial_omap_console_ports[co->index];
1310 
1311 	if (options)
1312 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1313 
1314 	return uart_set_options(&up->port, co, baud, parity, bits, flow);
1315 }
1316 
1317 static struct console serial_omap_console = {
1318 	.name		= OMAP_SERIAL_NAME,
1319 	.write		= serial_omap_console_write,
1320 	.device		= uart_console_device,
1321 	.setup		= serial_omap_console_setup,
1322 	.flags		= CON_PRINTBUFFER,
1323 	.index		= -1,
1324 	.data		= &serial_omap_reg,
1325 };
1326 
1327 static void serial_omap_add_console_port(struct uart_omap_port *up)
1328 {
1329 	serial_omap_console_ports[up->port.line] = up;
1330 }
1331 
1332 #define OMAP_CONSOLE	(&serial_omap_console)
1333 
1334 #else
1335 
1336 #define OMAP_CONSOLE	NULL
1337 
1338 static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1339 {}
1340 
1341 #endif
1342 
1343 /* Enable or disable the rs485 support */
1344 static void
1345 serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
1346 {
1347 	struct uart_omap_port *up = to_uart_omap_port(port);
1348 	unsigned long flags;
1349 	unsigned int mode;
1350 	int val;
1351 
1352 	pm_runtime_get_sync(up->dev);
1353 	spin_lock_irqsave(&up->port.lock, flags);
1354 
1355 	/* Disable interrupts from this port */
1356 	mode = up->ier;
1357 	up->ier = 0;
1358 	serial_out(up, UART_IER, 0);
1359 
1360 	/* store new config */
1361 	up->rs485 = *rs485conf;
1362 
1363 	/*
1364 	 * Just as a precaution, only allow rs485
1365 	 * to be enabled if the gpio pin is valid
1366 	 */
1367 	if (gpio_is_valid(up->rts_gpio)) {
1368 		/* enable / disable rts */
1369 		val = (up->rs485.flags & SER_RS485_ENABLED) ?
1370 			SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
1371 		val = (up->rs485.flags & val) ? 1 : 0;
1372 		gpio_set_value(up->rts_gpio, val);
1373 	} else
1374 		up->rs485.flags &= ~SER_RS485_ENABLED;
1375 
1376 	/* Enable interrupts */
1377 	up->ier = mode;
1378 	serial_out(up, UART_IER, up->ier);
1379 
1380 	/* If RS-485 is disabled, make sure the THR interrupt is fired when
1381 	 * TX FIFO is below the trigger level.
1382 	 */
1383 	if (!(up->rs485.flags & SER_RS485_ENABLED) &&
1384 	    (up->scr & OMAP_UART_SCR_TX_EMPTY)) {
1385 		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
1386 		serial_out(up, UART_OMAP_SCR, up->scr);
1387 	}
1388 
1389 	spin_unlock_irqrestore(&up->port.lock, flags);
1390 	pm_runtime_mark_last_busy(up->dev);
1391 	pm_runtime_put_autosuspend(up->dev);
1392 }
1393 
1394 static int
1395 serial_omap_ioctl(struct uart_port *port, unsigned int cmd, unsigned long arg)
1396 {
1397 	struct serial_rs485 rs485conf;
1398 
1399 	switch (cmd) {
1400 	case TIOCSRS485:
1401 		if (copy_from_user(&rs485conf, (void __user *) arg,
1402 					sizeof(rs485conf)))
1403 			return -EFAULT;
1404 
1405 		serial_omap_config_rs485(port, &rs485conf);
1406 		break;
1407 
1408 	case TIOCGRS485:
1409 		if (copy_to_user((void __user *) arg,
1410 					&(to_uart_omap_port(port)->rs485),
1411 					sizeof(rs485conf)))
1412 			return -EFAULT;
1413 		break;
1414 
1415 	default:
1416 		return -ENOIOCTLCMD;
1417 	}
1418 	return 0;
1419 }
1420 
1421 
1422 static struct uart_ops serial_omap_pops = {
1423 	.tx_empty	= serial_omap_tx_empty,
1424 	.set_mctrl	= serial_omap_set_mctrl,
1425 	.get_mctrl	= serial_omap_get_mctrl,
1426 	.stop_tx	= serial_omap_stop_tx,
1427 	.start_tx	= serial_omap_start_tx,
1428 	.throttle	= serial_omap_throttle,
1429 	.unthrottle	= serial_omap_unthrottle,
1430 	.stop_rx	= serial_omap_stop_rx,
1431 	.enable_ms	= serial_omap_enable_ms,
1432 	.break_ctl	= serial_omap_break_ctl,
1433 	.startup	= serial_omap_startup,
1434 	.shutdown	= serial_omap_shutdown,
1435 	.set_termios	= serial_omap_set_termios,
1436 	.pm		= serial_omap_pm,
1437 	.type		= serial_omap_type,
1438 	.release_port	= serial_omap_release_port,
1439 	.request_port	= serial_omap_request_port,
1440 	.config_port	= serial_omap_config_port,
1441 	.verify_port	= serial_omap_verify_port,
1442 	.ioctl		= serial_omap_ioctl,
1443 #ifdef CONFIG_CONSOLE_POLL
1444 	.poll_put_char  = serial_omap_poll_put_char,
1445 	.poll_get_char  = serial_omap_poll_get_char,
1446 #endif
1447 };
1448 
1449 static struct uart_driver serial_omap_reg = {
1450 	.owner		= THIS_MODULE,
1451 	.driver_name	= "OMAP-SERIAL",
1452 	.dev_name	= OMAP_SERIAL_NAME,
1453 	.nr		= OMAP_MAX_HSUART_PORTS,
1454 	.cons		= OMAP_CONSOLE,
1455 };
1456 
1457 #ifdef CONFIG_PM_SLEEP
1458 static int serial_omap_prepare(struct device *dev)
1459 {
1460 	struct uart_omap_port *up = dev_get_drvdata(dev);
1461 
1462 	up->is_suspending = true;
1463 
1464 	return 0;
1465 }
1466 
1467 static void serial_omap_complete(struct device *dev)
1468 {
1469 	struct uart_omap_port *up = dev_get_drvdata(dev);
1470 
1471 	up->is_suspending = false;
1472 }
1473 
1474 static int serial_omap_suspend(struct device *dev)
1475 {
1476 	struct uart_omap_port *up = dev_get_drvdata(dev);
1477 
1478 	uart_suspend_port(&serial_omap_reg, &up->port);
1479 	flush_work(&up->qos_work);
1480 
1481 	if (device_may_wakeup(dev))
1482 		serial_omap_enable_wakeup(up, true);
1483 	else
1484 		serial_omap_enable_wakeup(up, false);
1485 
1486 	return 0;
1487 }
1488 
1489 static int serial_omap_resume(struct device *dev)
1490 {
1491 	struct uart_omap_port *up = dev_get_drvdata(dev);
1492 
1493 	if (device_may_wakeup(dev))
1494 		serial_omap_enable_wakeup(up, false);
1495 
1496 	uart_resume_port(&serial_omap_reg, &up->port);
1497 
1498 	return 0;
1499 }
1500 #else
1501 #define serial_omap_prepare NULL
1502 #define serial_omap_complete NULL
1503 #endif /* CONFIG_PM_SLEEP */
1504 
1505 static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
1506 {
1507 	u32 mvr, scheme;
1508 	u16 revision, major, minor;
1509 
1510 	mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
1511 
1512 	/* Check revision register scheme */
1513 	scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
1514 
1515 	switch (scheme) {
1516 	case 0: /* Legacy Scheme: OMAP2/3 */
1517 		/* MINOR_REV[0:4], MAJOR_REV[4:7] */
1518 		major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
1519 					OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
1520 		minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
1521 		break;
1522 	case 1:
1523 		/* New Scheme: OMAP4+ */
1524 		/* MINOR_REV[0:5], MAJOR_REV[8:10] */
1525 		major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
1526 					OMAP_UART_MVR_MAJ_SHIFT;
1527 		minor = (mvr & OMAP_UART_MVR_MIN_MASK);
1528 		break;
1529 	default:
1530 		dev_warn(up->dev,
1531 			"Unknown %s revision, defaulting to highest\n",
1532 			up->name);
1533 		/* highest possible revision */
1534 		major = 0xff;
1535 		minor = 0xff;
1536 	}
1537 
1538 	/* normalize revision for the driver */
1539 	revision = UART_BUILD_REVISION(major, minor);
1540 
1541 	switch (revision) {
1542 	case OMAP_UART_REV_46:
1543 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1544 				UART_ERRATA_i291_DMA_FORCEIDLE);
1545 		break;
1546 	case OMAP_UART_REV_52:
1547 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1548 				UART_ERRATA_i291_DMA_FORCEIDLE);
1549 		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1550 		break;
1551 	case OMAP_UART_REV_63:
1552 		up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
1553 		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1554 		break;
1555 	default:
1556 		break;
1557 	}
1558 }
1559 
1560 static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1561 {
1562 	struct omap_uart_port_info *omap_up_info;
1563 
1564 	omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1565 	if (!omap_up_info)
1566 		return NULL; /* out of memory */
1567 
1568 	of_property_read_u32(dev->of_node, "clock-frequency",
1569 					 &omap_up_info->uartclk);
1570 	return omap_up_info;
1571 }
1572 
1573 static int serial_omap_probe_rs485(struct uart_omap_port *up,
1574 				   struct device_node *np)
1575 {
1576 	struct serial_rs485 *rs485conf = &up->rs485;
1577 	u32 rs485_delay[2];
1578 	enum of_gpio_flags flags;
1579 	int ret;
1580 
1581 	rs485conf->flags = 0;
1582 	up->rts_gpio = -EINVAL;
1583 
1584 	if (!np)
1585 		return 0;
1586 
1587 	if (of_property_read_bool(np, "rs485-rts-active-high"))
1588 		rs485conf->flags |= SER_RS485_RTS_ON_SEND;
1589 	else
1590 		rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
1591 
1592 	/* check for tx enable gpio */
1593 	up->rts_gpio = of_get_named_gpio_flags(np, "rts-gpio", 0, &flags);
1594 	if (gpio_is_valid(up->rts_gpio)) {
1595 		ret = devm_gpio_request(up->dev, up->rts_gpio, "omap-serial");
1596 		if (ret < 0)
1597 			return ret;
1598 		ret = gpio_direction_output(up->rts_gpio,
1599 					    flags & SER_RS485_RTS_AFTER_SEND);
1600 		if (ret < 0)
1601 			return ret;
1602 	} else if (up->rts_gpio == -EPROBE_DEFER) {
1603 		return -EPROBE_DEFER;
1604 	} else {
1605 		up->rts_gpio = -EINVAL;
1606 	}
1607 
1608 	if (of_property_read_u32_array(np, "rs485-rts-delay",
1609 				    rs485_delay, 2) == 0) {
1610 		rs485conf->delay_rts_before_send = rs485_delay[0];
1611 		rs485conf->delay_rts_after_send = rs485_delay[1];
1612 	}
1613 
1614 	if (of_property_read_bool(np, "rs485-rx-during-tx"))
1615 		rs485conf->flags |= SER_RS485_RX_DURING_TX;
1616 
1617 	if (of_property_read_bool(np, "linux,rs485-enabled-at-boot-time"))
1618 		rs485conf->flags |= SER_RS485_ENABLED;
1619 
1620 	return 0;
1621 }
1622 
1623 static int serial_omap_probe(struct platform_device *pdev)
1624 {
1625 	struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
1626 	struct uart_omap_port *up;
1627 	struct resource *mem;
1628 	void __iomem *base;
1629 	int uartirq = 0;
1630 	int wakeirq = 0;
1631 	int ret;
1632 
1633 	/* The optional wakeirq may be specified in the board dts file */
1634 	if (pdev->dev.of_node) {
1635 		uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0);
1636 		if (!uartirq)
1637 			return -EPROBE_DEFER;
1638 		wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
1639 		omap_up_info = of_get_uart_port_info(&pdev->dev);
1640 		pdev->dev.platform_data = omap_up_info;
1641 	} else {
1642 		uartirq = platform_get_irq(pdev, 0);
1643 		if (uartirq < 0)
1644 			return -EPROBE_DEFER;
1645 	}
1646 
1647 	up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
1648 	if (!up)
1649 		return -ENOMEM;
1650 
1651 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1652 	base = devm_ioremap_resource(&pdev->dev, mem);
1653 	if (IS_ERR(base))
1654 		return PTR_ERR(base);
1655 
1656 	up->dev = &pdev->dev;
1657 	up->port.dev = &pdev->dev;
1658 	up->port.type = PORT_OMAP;
1659 	up->port.iotype = UPIO_MEM;
1660 	up->port.irq = uartirq;
1661 	up->wakeirq = wakeirq;
1662 	if (!up->wakeirq)
1663 		dev_info(up->port.dev, "no wakeirq for uart%d\n",
1664 			 up->port.line);
1665 
1666 	up->port.regshift = 2;
1667 	up->port.fifosize = 64;
1668 	up->port.ops = &serial_omap_pops;
1669 
1670 	if (pdev->dev.of_node)
1671 		up->port.line = of_alias_get_id(pdev->dev.of_node, "serial");
1672 	else
1673 		up->port.line = pdev->id;
1674 
1675 	if (up->port.line < 0) {
1676 		dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1677 								up->port.line);
1678 		ret = -ENODEV;
1679 		goto err_port_line;
1680 	}
1681 
1682 	ret = serial_omap_probe_rs485(up, pdev->dev.of_node);
1683 	if (ret < 0)
1684 		goto err_rs485;
1685 
1686 	sprintf(up->name, "OMAP UART%d", up->port.line);
1687 	up->port.mapbase = mem->start;
1688 	up->port.membase = base;
1689 	up->port.flags = omap_up_info->flags;
1690 	up->port.uartclk = omap_up_info->uartclk;
1691 	if (!up->port.uartclk) {
1692 		up->port.uartclk = DEFAULT_CLK_SPEED;
1693 		dev_warn(&pdev->dev,
1694 			 "No clock speed specified: using default: %d\n",
1695 			 DEFAULT_CLK_SPEED);
1696 	}
1697 
1698 	up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1699 	up->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1700 	pm_qos_add_request(&up->pm_qos_request,
1701 		PM_QOS_CPU_DMA_LATENCY, up->latency);
1702 	INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1703 
1704 	platform_set_drvdata(pdev, up);
1705 	if (omap_up_info->autosuspend_timeout == 0)
1706 		omap_up_info->autosuspend_timeout = -1;
1707 
1708 	device_init_wakeup(up->dev, true);
1709 	pm_runtime_use_autosuspend(&pdev->dev);
1710 	pm_runtime_set_autosuspend_delay(&pdev->dev,
1711 			omap_up_info->autosuspend_timeout);
1712 
1713 	pm_runtime_irq_safe(&pdev->dev);
1714 	pm_runtime_enable(&pdev->dev);
1715 
1716 	pm_runtime_get_sync(&pdev->dev);
1717 
1718 	omap_serial_fill_features_erratas(up);
1719 
1720 	ui[up->port.line] = up;
1721 	serial_omap_add_console_port(up);
1722 
1723 	ret = uart_add_one_port(&serial_omap_reg, &up->port);
1724 	if (ret != 0)
1725 		goto err_add_port;
1726 
1727 	pm_runtime_mark_last_busy(up->dev);
1728 	pm_runtime_put_autosuspend(up->dev);
1729 	return 0;
1730 
1731 err_add_port:
1732 	pm_runtime_put(&pdev->dev);
1733 	pm_runtime_disable(&pdev->dev);
1734 err_rs485:
1735 err_port_line:
1736 	dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n",
1737 				pdev->id, __func__, ret);
1738 	return ret;
1739 }
1740 
1741 static int serial_omap_remove(struct platform_device *dev)
1742 {
1743 	struct uart_omap_port *up = platform_get_drvdata(dev);
1744 
1745 	pm_runtime_put_sync(up->dev);
1746 	pm_runtime_disable(up->dev);
1747 	uart_remove_one_port(&serial_omap_reg, &up->port);
1748 	pm_qos_remove_request(&up->pm_qos_request);
1749 	device_init_wakeup(&dev->dev, false);
1750 
1751 	return 0;
1752 }
1753 
1754 /*
1755  * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1756  * The access to uart register after MDR1 Access
1757  * causes UART to corrupt data.
1758  *
1759  * Need a delay =
1760  * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1761  * give 10 times as much
1762  */
1763 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1764 {
1765 	u8 timeout = 255;
1766 
1767 	serial_out(up, UART_OMAP_MDR1, mdr1);
1768 	udelay(2);
1769 	serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1770 			UART_FCR_CLEAR_RCVR);
1771 	/*
1772 	 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1773 	 * TX_FIFO_E bit is 1.
1774 	 */
1775 	while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1776 				(UART_LSR_THRE | UART_LSR_DR))) {
1777 		timeout--;
1778 		if (!timeout) {
1779 			/* Should *never* happen. we warn and carry on */
1780 			dev_crit(up->dev, "Errata i202: timedout %x\n",
1781 						serial_in(up, UART_LSR));
1782 			break;
1783 		}
1784 		udelay(1);
1785 	}
1786 }
1787 
1788 #ifdef CONFIG_PM_RUNTIME
1789 static void serial_omap_restore_context(struct uart_omap_port *up)
1790 {
1791 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1792 		serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1793 	else
1794 		serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1795 
1796 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1797 	serial_out(up, UART_EFR, UART_EFR_ECB);
1798 	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1799 	serial_out(up, UART_IER, 0x0);
1800 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1801 	serial_out(up, UART_DLL, up->dll);
1802 	serial_out(up, UART_DLM, up->dlh);
1803 	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1804 	serial_out(up, UART_IER, up->ier);
1805 	serial_out(up, UART_FCR, up->fcr);
1806 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1807 	serial_out(up, UART_MCR, up->mcr);
1808 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1809 	serial_out(up, UART_OMAP_SCR, up->scr);
1810 	serial_out(up, UART_EFR, up->efr);
1811 	serial_out(up, UART_LCR, up->lcr);
1812 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1813 		serial_omap_mdr1_errataset(up, up->mdr1);
1814 	else
1815 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1816 	serial_out(up, UART_OMAP_WER, up->wer);
1817 }
1818 
1819 static int serial_omap_runtime_suspend(struct device *dev)
1820 {
1821 	struct uart_omap_port *up = dev_get_drvdata(dev);
1822 
1823 	if (!up)
1824 		return -EINVAL;
1825 
1826 	/*
1827 	* When using 'no_console_suspend', the console UART must not be
1828 	* suspended. Since driver suspend is managed by runtime suspend,
1829 	* preventing runtime suspend (by returning error) will keep device
1830 	* active during suspend.
1831 	*/
1832 	if (up->is_suspending && !console_suspend_enabled &&
1833 	    uart_console(&up->port))
1834 		return -EBUSY;
1835 
1836 	up->context_loss_cnt = serial_omap_get_context_loss_count(up);
1837 
1838 	serial_omap_enable_wakeup(up, true);
1839 
1840 	up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1841 	schedule_work(&up->qos_work);
1842 
1843 	return 0;
1844 }
1845 
1846 static int serial_omap_runtime_resume(struct device *dev)
1847 {
1848 	struct uart_omap_port *up = dev_get_drvdata(dev);
1849 
1850 	int loss_cnt = serial_omap_get_context_loss_count(up);
1851 
1852 	serial_omap_enable_wakeup(up, false);
1853 
1854 	if (loss_cnt < 0) {
1855 		dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
1856 			loss_cnt);
1857 		serial_omap_restore_context(up);
1858 	} else if (up->context_loss_cnt != loss_cnt) {
1859 		serial_omap_restore_context(up);
1860 	}
1861 	up->latency = up->calc_latency;
1862 	schedule_work(&up->qos_work);
1863 
1864 	return 0;
1865 }
1866 #endif
1867 
1868 static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1869 	SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1870 	SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1871 				serial_omap_runtime_resume, NULL)
1872 	.prepare        = serial_omap_prepare,
1873 	.complete       = serial_omap_complete,
1874 };
1875 
1876 #if defined(CONFIG_OF)
1877 static const struct of_device_id omap_serial_of_match[] = {
1878 	{ .compatible = "ti,omap2-uart" },
1879 	{ .compatible = "ti,omap3-uart" },
1880 	{ .compatible = "ti,omap4-uart" },
1881 	{},
1882 };
1883 MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1884 #endif
1885 
1886 static struct platform_driver serial_omap_driver = {
1887 	.probe          = serial_omap_probe,
1888 	.remove         = serial_omap_remove,
1889 	.driver		= {
1890 		.name	= DRIVER_NAME,
1891 		.pm	= &serial_omap_dev_pm_ops,
1892 		.of_match_table = of_match_ptr(omap_serial_of_match),
1893 	},
1894 };
1895 
1896 static int __init serial_omap_init(void)
1897 {
1898 	int ret;
1899 
1900 	ret = uart_register_driver(&serial_omap_reg);
1901 	if (ret != 0)
1902 		return ret;
1903 	ret = platform_driver_register(&serial_omap_driver);
1904 	if (ret != 0)
1905 		uart_unregister_driver(&serial_omap_reg);
1906 	return ret;
1907 }
1908 
1909 static void __exit serial_omap_exit(void)
1910 {
1911 	platform_driver_unregister(&serial_omap_driver);
1912 	uart_unregister_driver(&serial_omap_reg);
1913 }
1914 
1915 module_init(serial_omap_init);
1916 module_exit(serial_omap_exit);
1917 
1918 MODULE_DESCRIPTION("OMAP High Speed UART driver");
1919 MODULE_LICENSE("GPL");
1920 MODULE_AUTHOR("Texas Instruments Inc");
1921