xref: /linux/drivers/tty/serial/omap-serial.c (revision 1ef24960ab78554fe7e8e77d8fc86524fbd60d3c)
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  * Calculate the absolute difference between the desired and actual baud
243  * rate for the given mode.
244  */
245 static inline int calculate_baud_abs_diff(struct uart_port *port,
246 				unsigned int baud, unsigned int mode)
247 {
248 	unsigned int n = port->uartclk / (mode * baud);
249 	int abs_diff;
250 
251 	if (n == 0)
252 		n = 1;
253 
254 	abs_diff = baud - (port->uartclk / (mode * n));
255 	if (abs_diff < 0)
256 		abs_diff = -abs_diff;
257 
258 	return abs_diff;
259 }
260 
261 /*
262  * serial_omap_baud_is_mode16 - check if baud rate is MODE16X
263  * @port: uart port info
264  * @baud: baudrate for which mode needs to be determined
265  *
266  * Returns true if baud rate is MODE16X and false if MODE13X
267  * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
268  * and Error Rates" determines modes not for all common baud rates.
269  * E.g. for 1000000 baud rate mode must be 16x, but according to that
270  * table it's determined as 13x.
271  */
272 static bool
273 serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
274 {
275 	int abs_diff_13 = calculate_baud_abs_diff(port, baud, 13);
276 	int abs_diff_16 = calculate_baud_abs_diff(port, baud, 16);
277 
278 	return (abs_diff_13 >= abs_diff_16);
279 }
280 
281 /*
282  * serial_omap_get_divisor - calculate divisor value
283  * @port: uart port info
284  * @baud: baudrate for which divisor needs to be calculated.
285  */
286 static unsigned int
287 serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
288 {
289 	unsigned int mode;
290 
291 	if (!serial_omap_baud_is_mode16(port, baud))
292 		mode = 13;
293 	else
294 		mode = 16;
295 	return port->uartclk/(mode * baud);
296 }
297 
298 static void serial_omap_enable_ms(struct uart_port *port)
299 {
300 	struct uart_omap_port *up = to_uart_omap_port(port);
301 
302 	dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
303 
304 	pm_runtime_get_sync(up->dev);
305 	up->ier |= UART_IER_MSI;
306 	serial_out(up, UART_IER, up->ier);
307 	pm_runtime_mark_last_busy(up->dev);
308 	pm_runtime_put_autosuspend(up->dev);
309 }
310 
311 static void serial_omap_stop_tx(struct uart_port *port)
312 {
313 	struct uart_omap_port *up = to_uart_omap_port(port);
314 	int res;
315 
316 	pm_runtime_get_sync(up->dev);
317 
318 	/* Handle RS-485 */
319 	if (up->rs485.flags & SER_RS485_ENABLED) {
320 		if (up->scr & OMAP_UART_SCR_TX_EMPTY) {
321 			/* THR interrupt is fired when both TX FIFO and TX
322 			 * shift register are empty. This means there's nothing
323 			 * left to transmit now, so make sure the THR interrupt
324 			 * is fired when TX FIFO is below the trigger level,
325 			 * disable THR interrupts and toggle the RS-485 GPIO
326 			 * data direction pin if needed.
327 			 */
328 			up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
329 			serial_out(up, UART_OMAP_SCR, up->scr);
330 			res = (up->rs485.flags & SER_RS485_RTS_AFTER_SEND) ? 1 : 0;
331 			if (gpio_get_value(up->rts_gpio) != res) {
332 				if (up->rs485.delay_rts_after_send > 0)
333 					mdelay(up->rs485.delay_rts_after_send);
334 				gpio_set_value(up->rts_gpio, res);
335 			}
336 		} else {
337 			/* We're asked to stop, but there's still stuff in the
338 			 * UART FIFO, so make sure the THR interrupt is fired
339 			 * when both TX FIFO and TX shift register are empty.
340 			 * The next THR interrupt (if no transmission is started
341 			 * in the meantime) will indicate the end of a
342 			 * transmission. Therefore we _don't_ disable THR
343 			 * interrupts in this situation.
344 			 */
345 			up->scr |= OMAP_UART_SCR_TX_EMPTY;
346 			serial_out(up, UART_OMAP_SCR, up->scr);
347 			return;
348 		}
349 	}
350 
351 	if (up->ier & UART_IER_THRI) {
352 		up->ier &= ~UART_IER_THRI;
353 		serial_out(up, UART_IER, up->ier);
354 	}
355 
356 	if ((up->rs485.flags & SER_RS485_ENABLED) &&
357 	    !(up->rs485.flags & SER_RS485_RX_DURING_TX)) {
358 		/*
359 		 * Empty the RX FIFO, we are not interested in anything
360 		 * received during the half-duplex transmission.
361 		 */
362 		serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_RCVR);
363 		/* Re-enable RX interrupts */
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 	}
368 
369 	pm_runtime_mark_last_busy(up->dev);
370 	pm_runtime_put_autosuspend(up->dev);
371 }
372 
373 static void serial_omap_stop_rx(struct uart_port *port)
374 {
375 	struct uart_omap_port *up = to_uart_omap_port(port);
376 
377 	pm_runtime_get_sync(up->dev);
378 	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
379 	up->port.read_status_mask &= ~UART_LSR_DR;
380 	serial_out(up, UART_IER, up->ier);
381 	pm_runtime_mark_last_busy(up->dev);
382 	pm_runtime_put_autosuspend(up->dev);
383 }
384 
385 static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
386 {
387 	struct circ_buf *xmit = &up->port.state->xmit;
388 	int count;
389 
390 	if (up->port.x_char) {
391 		serial_out(up, UART_TX, up->port.x_char);
392 		up->port.icount.tx++;
393 		up->port.x_char = 0;
394 		return;
395 	}
396 	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
397 		serial_omap_stop_tx(&up->port);
398 		return;
399 	}
400 	count = up->port.fifosize / 4;
401 	do {
402 		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
403 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
404 		up->port.icount.tx++;
405 		if (uart_circ_empty(xmit))
406 			break;
407 	} while (--count > 0);
408 
409 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
410 		uart_write_wakeup(&up->port);
411 
412 	if (uart_circ_empty(xmit))
413 		serial_omap_stop_tx(&up->port);
414 }
415 
416 static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
417 {
418 	if (!(up->ier & UART_IER_THRI)) {
419 		up->ier |= UART_IER_THRI;
420 		serial_out(up, UART_IER, up->ier);
421 	}
422 }
423 
424 static void serial_omap_start_tx(struct uart_port *port)
425 {
426 	struct uart_omap_port *up = to_uart_omap_port(port);
427 	int res;
428 
429 	pm_runtime_get_sync(up->dev);
430 
431 	/* Handle RS-485 */
432 	if (up->rs485.flags & SER_RS485_ENABLED) {
433 		/* Fire THR interrupts when FIFO is below trigger level */
434 		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
435 		serial_out(up, UART_OMAP_SCR, up->scr);
436 
437 		/* if rts not already enabled */
438 		res = (up->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
439 		if (gpio_get_value(up->rts_gpio) != res) {
440 			gpio_set_value(up->rts_gpio, res);
441 			if (up->rs485.delay_rts_before_send > 0)
442 				mdelay(up->rs485.delay_rts_before_send);
443 		}
444 	}
445 
446 	if ((up->rs485.flags & SER_RS485_ENABLED) &&
447 	    !(up->rs485.flags & SER_RS485_RX_DURING_TX))
448 		serial_omap_stop_rx(port);
449 
450 	serial_omap_enable_ier_thri(up);
451 	pm_runtime_mark_last_busy(up->dev);
452 	pm_runtime_put_autosuspend(up->dev);
453 }
454 
455 static void serial_omap_throttle(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 void serial_omap_unthrottle(struct uart_port *port)
470 {
471 	struct uart_omap_port *up = to_uart_omap_port(port);
472 	unsigned long flags;
473 
474 	pm_runtime_get_sync(up->dev);
475 	spin_lock_irqsave(&up->port.lock, flags);
476 	up->ier |= UART_IER_RLSI | UART_IER_RDI;
477 	serial_out(up, UART_IER, up->ier);
478 	spin_unlock_irqrestore(&up->port.lock, flags);
479 	pm_runtime_mark_last_busy(up->dev);
480 	pm_runtime_put_autosuspend(up->dev);
481 }
482 
483 static unsigned int check_modem_status(struct uart_omap_port *up)
484 {
485 	unsigned int status;
486 
487 	status = serial_in(up, UART_MSR);
488 	status |= up->msr_saved_flags;
489 	up->msr_saved_flags = 0;
490 	if ((status & UART_MSR_ANY_DELTA) == 0)
491 		return status;
492 
493 	if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
494 	    up->port.state != NULL) {
495 		if (status & UART_MSR_TERI)
496 			up->port.icount.rng++;
497 		if (status & UART_MSR_DDSR)
498 			up->port.icount.dsr++;
499 		if (status & UART_MSR_DDCD)
500 			uart_handle_dcd_change
501 				(&up->port, status & UART_MSR_DCD);
502 		if (status & UART_MSR_DCTS)
503 			uart_handle_cts_change
504 				(&up->port, status & UART_MSR_CTS);
505 		wake_up_interruptible(&up->port.state->port.delta_msr_wait);
506 	}
507 
508 	return status;
509 }
510 
511 static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
512 {
513 	unsigned int flag;
514 	unsigned char ch = 0;
515 
516 	if (likely(lsr & UART_LSR_DR))
517 		ch = serial_in(up, UART_RX);
518 
519 	up->port.icount.rx++;
520 	flag = TTY_NORMAL;
521 
522 	if (lsr & UART_LSR_BI) {
523 		flag = TTY_BREAK;
524 		lsr &= ~(UART_LSR_FE | UART_LSR_PE);
525 		up->port.icount.brk++;
526 		/*
527 		 * We do the SysRQ and SAK checking
528 		 * here because otherwise the break
529 		 * may get masked by ignore_status_mask
530 		 * or read_status_mask.
531 		 */
532 		if (uart_handle_break(&up->port))
533 			return;
534 
535 	}
536 
537 	if (lsr & UART_LSR_PE) {
538 		flag = TTY_PARITY;
539 		up->port.icount.parity++;
540 	}
541 
542 	if (lsr & UART_LSR_FE) {
543 		flag = TTY_FRAME;
544 		up->port.icount.frame++;
545 	}
546 
547 	if (lsr & UART_LSR_OE)
548 		up->port.icount.overrun++;
549 
550 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
551 	if (up->port.line == up->port.cons->index) {
552 		/* Recover the break flag from console xmit */
553 		lsr |= up->lsr_break_flag;
554 	}
555 #endif
556 	uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag);
557 }
558 
559 static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
560 {
561 	unsigned char ch = 0;
562 	unsigned int flag;
563 
564 	if (!(lsr & UART_LSR_DR))
565 		return;
566 
567 	ch = serial_in(up, UART_RX);
568 	flag = TTY_NORMAL;
569 	up->port.icount.rx++;
570 
571 	if (uart_handle_sysrq_char(&up->port, ch))
572 		return;
573 
574 	uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
575 }
576 
577 /**
578  * serial_omap_irq() - This handles the interrupt from one port
579  * @irq: uart port irq number
580  * @dev_id: uart port info
581  */
582 static irqreturn_t serial_omap_irq(int irq, void *dev_id)
583 {
584 	struct uart_omap_port *up = dev_id;
585 	unsigned int iir, lsr;
586 	unsigned int type;
587 	irqreturn_t ret = IRQ_NONE;
588 	int max_count = 256;
589 
590 	spin_lock(&up->port.lock);
591 	pm_runtime_get_sync(up->dev);
592 
593 	do {
594 		iir = serial_in(up, UART_IIR);
595 		if (iir & UART_IIR_NO_INT)
596 			break;
597 
598 		ret = IRQ_HANDLED;
599 		lsr = serial_in(up, UART_LSR);
600 
601 		/* extract IRQ type from IIR register */
602 		type = iir & 0x3e;
603 
604 		switch (type) {
605 		case UART_IIR_MSI:
606 			check_modem_status(up);
607 			break;
608 		case UART_IIR_THRI:
609 			transmit_chars(up, lsr);
610 			break;
611 		case UART_IIR_RX_TIMEOUT:
612 			/* FALLTHROUGH */
613 		case UART_IIR_RDI:
614 			serial_omap_rdi(up, lsr);
615 			break;
616 		case UART_IIR_RLSI:
617 			serial_omap_rlsi(up, lsr);
618 			break;
619 		case UART_IIR_CTS_RTS_DSR:
620 			/* simply try again */
621 			break;
622 		case UART_IIR_XOFF:
623 			/* FALLTHROUGH */
624 		default:
625 			break;
626 		}
627 	} while (!(iir & UART_IIR_NO_INT) && max_count--);
628 
629 	spin_unlock(&up->port.lock);
630 
631 	tty_flip_buffer_push(&up->port.state->port);
632 
633 	pm_runtime_mark_last_busy(up->dev);
634 	pm_runtime_put_autosuspend(up->dev);
635 	up->port_activity = jiffies;
636 
637 	return ret;
638 }
639 
640 static unsigned int serial_omap_tx_empty(struct uart_port *port)
641 {
642 	struct uart_omap_port *up = to_uart_omap_port(port);
643 	unsigned long flags = 0;
644 	unsigned int ret = 0;
645 
646 	pm_runtime_get_sync(up->dev);
647 	dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
648 	spin_lock_irqsave(&up->port.lock, flags);
649 	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
650 	spin_unlock_irqrestore(&up->port.lock, flags);
651 	pm_runtime_mark_last_busy(up->dev);
652 	pm_runtime_put_autosuspend(up->dev);
653 	return ret;
654 }
655 
656 static unsigned int serial_omap_get_mctrl(struct uart_port *port)
657 {
658 	struct uart_omap_port *up = to_uart_omap_port(port);
659 	unsigned int status;
660 	unsigned int ret = 0;
661 
662 	pm_runtime_get_sync(up->dev);
663 	status = check_modem_status(up);
664 	pm_runtime_mark_last_busy(up->dev);
665 	pm_runtime_put_autosuspend(up->dev);
666 
667 	dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
668 
669 	if (status & UART_MSR_DCD)
670 		ret |= TIOCM_CAR;
671 	if (status & UART_MSR_RI)
672 		ret |= TIOCM_RNG;
673 	if (status & UART_MSR_DSR)
674 		ret |= TIOCM_DSR;
675 	if (status & UART_MSR_CTS)
676 		ret |= TIOCM_CTS;
677 	return ret;
678 }
679 
680 static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
681 {
682 	struct uart_omap_port *up = to_uart_omap_port(port);
683 	unsigned char mcr = 0, old_mcr;
684 
685 	dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
686 	if (mctrl & TIOCM_RTS)
687 		mcr |= UART_MCR_RTS;
688 	if (mctrl & TIOCM_DTR)
689 		mcr |= UART_MCR_DTR;
690 	if (mctrl & TIOCM_OUT1)
691 		mcr |= UART_MCR_OUT1;
692 	if (mctrl & TIOCM_OUT2)
693 		mcr |= UART_MCR_OUT2;
694 	if (mctrl & TIOCM_LOOP)
695 		mcr |= UART_MCR_LOOP;
696 
697 	pm_runtime_get_sync(up->dev);
698 	old_mcr = serial_in(up, UART_MCR);
699 	old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
700 		     UART_MCR_DTR | UART_MCR_RTS);
701 	up->mcr = old_mcr | mcr;
702 	serial_out(up, UART_MCR, up->mcr);
703 	pm_runtime_mark_last_busy(up->dev);
704 	pm_runtime_put_autosuspend(up->dev);
705 }
706 
707 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
708 {
709 	struct uart_omap_port *up = to_uart_omap_port(port);
710 	unsigned long flags = 0;
711 
712 	dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
713 	pm_runtime_get_sync(up->dev);
714 	spin_lock_irqsave(&up->port.lock, flags);
715 	if (break_state == -1)
716 		up->lcr |= UART_LCR_SBC;
717 	else
718 		up->lcr &= ~UART_LCR_SBC;
719 	serial_out(up, UART_LCR, up->lcr);
720 	spin_unlock_irqrestore(&up->port.lock, flags);
721 	pm_runtime_mark_last_busy(up->dev);
722 	pm_runtime_put_autosuspend(up->dev);
723 }
724 
725 static int serial_omap_startup(struct uart_port *port)
726 {
727 	struct uart_omap_port *up = to_uart_omap_port(port);
728 	unsigned long flags = 0;
729 	int retval;
730 
731 	/*
732 	 * Allocate the IRQ
733 	 */
734 	retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
735 				up->name, up);
736 	if (retval)
737 		return retval;
738 
739 	/* Optional wake-up IRQ */
740 	if (up->wakeirq) {
741 		retval = request_irq(up->wakeirq, serial_omap_irq,
742 				     up->port.irqflags, up->name, up);
743 		if (retval) {
744 			free_irq(up->port.irq, up);
745 			return retval;
746 		}
747 		disable_irq(up->wakeirq);
748 	}
749 
750 	dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
751 
752 	pm_runtime_get_sync(up->dev);
753 	/*
754 	 * Clear the FIFO buffers and disable them.
755 	 * (they will be reenabled in set_termios())
756 	 */
757 	serial_omap_clear_fifos(up);
758 	/* For Hardware flow control */
759 	serial_out(up, UART_MCR, UART_MCR_RTS);
760 
761 	/*
762 	 * Clear the interrupt registers.
763 	 */
764 	(void) serial_in(up, UART_LSR);
765 	if (serial_in(up, UART_LSR) & UART_LSR_DR)
766 		(void) serial_in(up, UART_RX);
767 	(void) serial_in(up, UART_IIR);
768 	(void) serial_in(up, UART_MSR);
769 
770 	/*
771 	 * Now, initialize the UART
772 	 */
773 	serial_out(up, UART_LCR, UART_LCR_WLEN8);
774 	spin_lock_irqsave(&up->port.lock, flags);
775 	/*
776 	 * Most PC uarts need OUT2 raised to enable interrupts.
777 	 */
778 	up->port.mctrl |= TIOCM_OUT2;
779 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
780 	spin_unlock_irqrestore(&up->port.lock, flags);
781 
782 	up->msr_saved_flags = 0;
783 	/*
784 	 * Finally, enable interrupts. Note: Modem status interrupts
785 	 * are set via set_termios(), which will be occurring imminently
786 	 * anyway, so we don't enable them here.
787 	 */
788 	up->ier = UART_IER_RLSI | UART_IER_RDI;
789 	serial_out(up, UART_IER, up->ier);
790 
791 	/* Enable module level wake up */
792 	up->wer = OMAP_UART_WER_MOD_WKUP;
793 	if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
794 		up->wer |= OMAP_UART_TX_WAKEUP_EN;
795 
796 	serial_out(up, UART_OMAP_WER, up->wer);
797 
798 	pm_runtime_mark_last_busy(up->dev);
799 	pm_runtime_put_autosuspend(up->dev);
800 	up->port_activity = jiffies;
801 	return 0;
802 }
803 
804 static void serial_omap_shutdown(struct uart_port *port)
805 {
806 	struct uart_omap_port *up = to_uart_omap_port(port);
807 	unsigned long flags = 0;
808 
809 	dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
810 
811 	pm_runtime_get_sync(up->dev);
812 	/*
813 	 * Disable interrupts from this port
814 	 */
815 	up->ier = 0;
816 	serial_out(up, UART_IER, 0);
817 
818 	spin_lock_irqsave(&up->port.lock, flags);
819 	up->port.mctrl &= ~TIOCM_OUT2;
820 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
821 	spin_unlock_irqrestore(&up->port.lock, flags);
822 
823 	/*
824 	 * Disable break condition and FIFOs
825 	 */
826 	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
827 	serial_omap_clear_fifos(up);
828 
829 	/*
830 	 * Read data port to reset things, and then free the irq
831 	 */
832 	if (serial_in(up, UART_LSR) & UART_LSR_DR)
833 		(void) serial_in(up, UART_RX);
834 
835 	pm_runtime_mark_last_busy(up->dev);
836 	pm_runtime_put_autosuspend(up->dev);
837 	free_irq(up->port.irq, up);
838 	if (up->wakeirq)
839 		free_irq(up->wakeirq, up);
840 }
841 
842 static void serial_omap_uart_qos_work(struct work_struct *work)
843 {
844 	struct uart_omap_port *up = container_of(work, struct uart_omap_port,
845 						qos_work);
846 
847 	pm_qos_update_request(&up->pm_qos_request, up->latency);
848 }
849 
850 static void
851 serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
852 			struct ktermios *old)
853 {
854 	struct uart_omap_port *up = to_uart_omap_port(port);
855 	unsigned char cval = 0;
856 	unsigned long flags = 0;
857 	unsigned int baud, quot;
858 
859 	switch (termios->c_cflag & CSIZE) {
860 	case CS5:
861 		cval = UART_LCR_WLEN5;
862 		break;
863 	case CS6:
864 		cval = UART_LCR_WLEN6;
865 		break;
866 	case CS7:
867 		cval = UART_LCR_WLEN7;
868 		break;
869 	default:
870 	case CS8:
871 		cval = UART_LCR_WLEN8;
872 		break;
873 	}
874 
875 	if (termios->c_cflag & CSTOPB)
876 		cval |= UART_LCR_STOP;
877 	if (termios->c_cflag & PARENB)
878 		cval |= UART_LCR_PARITY;
879 	if (!(termios->c_cflag & PARODD))
880 		cval |= UART_LCR_EPAR;
881 	if (termios->c_cflag & CMSPAR)
882 		cval |= UART_LCR_SPAR;
883 
884 	/*
885 	 * Ask the core to calculate the divisor for us.
886 	 */
887 
888 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
889 	quot = serial_omap_get_divisor(port, baud);
890 
891 	/* calculate wakeup latency constraint */
892 	up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
893 	up->latency = up->calc_latency;
894 	schedule_work(&up->qos_work);
895 
896 	up->dll = quot & 0xff;
897 	up->dlh = quot >> 8;
898 	up->mdr1 = UART_OMAP_MDR1_DISABLE;
899 
900 	up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
901 			UART_FCR_ENABLE_FIFO;
902 
903 	/*
904 	 * Ok, we're now changing the port state. Do it with
905 	 * interrupts disabled.
906 	 */
907 	pm_runtime_get_sync(up->dev);
908 	spin_lock_irqsave(&up->port.lock, flags);
909 
910 	/*
911 	 * Update the per-port timeout.
912 	 */
913 	uart_update_timeout(port, termios->c_cflag, baud);
914 
915 	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
916 	if (termios->c_iflag & INPCK)
917 		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
918 	if (termios->c_iflag & (BRKINT | PARMRK))
919 		up->port.read_status_mask |= UART_LSR_BI;
920 
921 	/*
922 	 * Characters to ignore
923 	 */
924 	up->port.ignore_status_mask = 0;
925 	if (termios->c_iflag & IGNPAR)
926 		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
927 	if (termios->c_iflag & IGNBRK) {
928 		up->port.ignore_status_mask |= UART_LSR_BI;
929 		/*
930 		 * If we're ignoring parity and break indicators,
931 		 * ignore overruns too (for real raw support).
932 		 */
933 		if (termios->c_iflag & IGNPAR)
934 			up->port.ignore_status_mask |= UART_LSR_OE;
935 	}
936 
937 	/*
938 	 * ignore all characters if CREAD is not set
939 	 */
940 	if ((termios->c_cflag & CREAD) == 0)
941 		up->port.ignore_status_mask |= UART_LSR_DR;
942 
943 	/*
944 	 * Modem status interrupts
945 	 */
946 	up->ier &= ~UART_IER_MSI;
947 	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
948 		up->ier |= UART_IER_MSI;
949 	serial_out(up, UART_IER, up->ier);
950 	serial_out(up, UART_LCR, cval);		/* reset DLAB */
951 	up->lcr = cval;
952 	up->scr = 0;
953 
954 	/* FIFOs and DMA Settings */
955 
956 	/* FCR can be changed only when the
957 	 * baud clock is not running
958 	 * DLL_REG and DLH_REG set to 0.
959 	 */
960 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
961 	serial_out(up, UART_DLL, 0);
962 	serial_out(up, UART_DLM, 0);
963 	serial_out(up, UART_LCR, 0);
964 
965 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
966 
967 	up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
968 	up->efr &= ~UART_EFR_SCD;
969 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
970 
971 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
972 	up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
973 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
974 	/* FIFO ENABLE, DMA MODE */
975 
976 	up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
977 	/*
978 	 * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
979 	 * sets Enables the granularity of 1 for TRIGGER RX
980 	 * level. Along with setting RX FIFO trigger level
981 	 * to 1 (as noted below, 16 characters) and TLR[3:0]
982 	 * to zero this will result RX FIFO threshold level
983 	 * to 1 character, instead of 16 as noted in comment
984 	 * below.
985 	 */
986 
987 	/* Set receive FIFO threshold to 16 characters and
988 	 * transmit FIFO threshold to 32 spaces
989 	 */
990 	up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
991 	up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
992 	up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
993 		UART_FCR_ENABLE_FIFO;
994 
995 	serial_out(up, UART_FCR, up->fcr);
996 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
997 
998 	serial_out(up, UART_OMAP_SCR, up->scr);
999 
1000 	/* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
1001 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1002 	serial_out(up, UART_MCR, up->mcr);
1003 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1004 	serial_out(up, UART_EFR, up->efr);
1005 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1006 
1007 	/* Protocol, Baud Rate, and Interrupt Settings */
1008 
1009 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1010 		serial_omap_mdr1_errataset(up, up->mdr1);
1011 	else
1012 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1013 
1014 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1015 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1016 
1017 	serial_out(up, UART_LCR, 0);
1018 	serial_out(up, UART_IER, 0);
1019 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1020 
1021 	serial_out(up, UART_DLL, up->dll);	/* LS of divisor */
1022 	serial_out(up, UART_DLM, up->dlh);	/* MS of divisor */
1023 
1024 	serial_out(up, UART_LCR, 0);
1025 	serial_out(up, UART_IER, up->ier);
1026 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1027 
1028 	serial_out(up, UART_EFR, up->efr);
1029 	serial_out(up, UART_LCR, cval);
1030 
1031 	if (!serial_omap_baud_is_mode16(port, baud))
1032 		up->mdr1 = UART_OMAP_MDR1_13X_MODE;
1033 	else
1034 		up->mdr1 = UART_OMAP_MDR1_16X_MODE;
1035 
1036 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1037 		serial_omap_mdr1_errataset(up, up->mdr1);
1038 	else
1039 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1040 
1041 	/* Configure flow control */
1042 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1043 
1044 	/* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
1045 	serial_out(up, UART_XON1, termios->c_cc[VSTART]);
1046 	serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
1047 
1048 	/* Enable access to TCR/TLR */
1049 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1050 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1051 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
1052 
1053 	serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
1054 
1055 	if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
1056 		/* Enable AUTORTS and AUTOCTS */
1057 		up->efr |= UART_EFR_CTS | UART_EFR_RTS;
1058 
1059 		/* Ensure MCR RTS is asserted */
1060 		up->mcr |= UART_MCR_RTS;
1061 	} else {
1062 		/* Disable AUTORTS and AUTOCTS */
1063 		up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
1064 	}
1065 
1066 	if (up->port.flags & UPF_SOFT_FLOW) {
1067 		/* clear SW control mode bits */
1068 		up->efr &= OMAP_UART_SW_CLR;
1069 
1070 		/*
1071 		 * IXON Flag:
1072 		 * Enable XON/XOFF flow control on input.
1073 		 * Receiver compares XON1, XOFF1.
1074 		 */
1075 		if (termios->c_iflag & IXON)
1076 			up->efr |= OMAP_UART_SW_RX;
1077 
1078 		/*
1079 		 * IXOFF Flag:
1080 		 * Enable XON/XOFF flow control on output.
1081 		 * Transmit XON1, XOFF1
1082 		 */
1083 		if (termios->c_iflag & IXOFF)
1084 			up->efr |= OMAP_UART_SW_TX;
1085 
1086 		/*
1087 		 * IXANY Flag:
1088 		 * Enable any character to restart output.
1089 		 * Operation resumes after receiving any
1090 		 * character after recognition of the XOFF character
1091 		 */
1092 		if (termios->c_iflag & IXANY)
1093 			up->mcr |= UART_MCR_XONANY;
1094 		else
1095 			up->mcr &= ~UART_MCR_XONANY;
1096 	}
1097 	serial_out(up, UART_MCR, up->mcr);
1098 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1099 	serial_out(up, UART_EFR, up->efr);
1100 	serial_out(up, UART_LCR, up->lcr);
1101 
1102 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
1103 
1104 	spin_unlock_irqrestore(&up->port.lock, flags);
1105 	pm_runtime_mark_last_busy(up->dev);
1106 	pm_runtime_put_autosuspend(up->dev);
1107 	dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
1108 }
1109 
1110 static void
1111 serial_omap_pm(struct uart_port *port, unsigned int state,
1112 	       unsigned int oldstate)
1113 {
1114 	struct uart_omap_port *up = to_uart_omap_port(port);
1115 	unsigned char efr;
1116 
1117 	dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
1118 
1119 	pm_runtime_get_sync(up->dev);
1120 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1121 	efr = serial_in(up, UART_EFR);
1122 	serial_out(up, UART_EFR, efr | UART_EFR_ECB);
1123 	serial_out(up, UART_LCR, 0);
1124 
1125 	serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
1126 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1127 	serial_out(up, UART_EFR, efr);
1128 	serial_out(up, UART_LCR, 0);
1129 
1130 	if (!device_may_wakeup(up->dev)) {
1131 		if (!state)
1132 			pm_runtime_forbid(up->dev);
1133 		else
1134 			pm_runtime_allow(up->dev);
1135 	}
1136 
1137 	pm_runtime_mark_last_busy(up->dev);
1138 	pm_runtime_put_autosuspend(up->dev);
1139 }
1140 
1141 static void serial_omap_release_port(struct uart_port *port)
1142 {
1143 	dev_dbg(port->dev, "serial_omap_release_port+\n");
1144 }
1145 
1146 static int serial_omap_request_port(struct uart_port *port)
1147 {
1148 	dev_dbg(port->dev, "serial_omap_request_port+\n");
1149 	return 0;
1150 }
1151 
1152 static void serial_omap_config_port(struct uart_port *port, int flags)
1153 {
1154 	struct uart_omap_port *up = to_uart_omap_port(port);
1155 
1156 	dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
1157 							up->port.line);
1158 	up->port.type = PORT_OMAP;
1159 	up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
1160 }
1161 
1162 static int
1163 serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
1164 {
1165 	/* we don't want the core code to modify any port params */
1166 	dev_dbg(port->dev, "serial_omap_verify_port+\n");
1167 	return -EINVAL;
1168 }
1169 
1170 static const char *
1171 serial_omap_type(struct uart_port *port)
1172 {
1173 	struct uart_omap_port *up = to_uart_omap_port(port);
1174 
1175 	dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
1176 	return up->name;
1177 }
1178 
1179 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1180 
1181 static inline void wait_for_xmitr(struct uart_omap_port *up)
1182 {
1183 	unsigned int status, tmout = 10000;
1184 
1185 	/* Wait up to 10ms for the character(s) to be sent. */
1186 	do {
1187 		status = serial_in(up, UART_LSR);
1188 
1189 		if (status & UART_LSR_BI)
1190 			up->lsr_break_flag = UART_LSR_BI;
1191 
1192 		if (--tmout == 0)
1193 			break;
1194 		udelay(1);
1195 	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
1196 
1197 	/* Wait up to 1s for flow control if necessary */
1198 	if (up->port.flags & UPF_CONS_FLOW) {
1199 		tmout = 1000000;
1200 		for (tmout = 1000000; tmout; tmout--) {
1201 			unsigned int msr = serial_in(up, UART_MSR);
1202 
1203 			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1204 			if (msr & UART_MSR_CTS)
1205 				break;
1206 
1207 			udelay(1);
1208 		}
1209 	}
1210 }
1211 
1212 #ifdef CONFIG_CONSOLE_POLL
1213 
1214 static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
1215 {
1216 	struct uart_omap_port *up = to_uart_omap_port(port);
1217 
1218 	pm_runtime_get_sync(up->dev);
1219 	wait_for_xmitr(up);
1220 	serial_out(up, UART_TX, ch);
1221 	pm_runtime_mark_last_busy(up->dev);
1222 	pm_runtime_put_autosuspend(up->dev);
1223 }
1224 
1225 static int serial_omap_poll_get_char(struct uart_port *port)
1226 {
1227 	struct uart_omap_port *up = to_uart_omap_port(port);
1228 	unsigned int status;
1229 
1230 	pm_runtime_get_sync(up->dev);
1231 	status = serial_in(up, UART_LSR);
1232 	if (!(status & UART_LSR_DR)) {
1233 		status = NO_POLL_CHAR;
1234 		goto out;
1235 	}
1236 
1237 	status = serial_in(up, UART_RX);
1238 
1239 out:
1240 	pm_runtime_mark_last_busy(up->dev);
1241 	pm_runtime_put_autosuspend(up->dev);
1242 
1243 	return status;
1244 }
1245 
1246 #endif /* CONFIG_CONSOLE_POLL */
1247 
1248 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
1249 
1250 static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
1251 
1252 static struct uart_driver serial_omap_reg;
1253 
1254 static void serial_omap_console_putchar(struct uart_port *port, int ch)
1255 {
1256 	struct uart_omap_port *up = to_uart_omap_port(port);
1257 
1258 	wait_for_xmitr(up);
1259 	serial_out(up, UART_TX, ch);
1260 }
1261 
1262 static void
1263 serial_omap_console_write(struct console *co, const char *s,
1264 		unsigned int count)
1265 {
1266 	struct uart_omap_port *up = serial_omap_console_ports[co->index];
1267 	unsigned long flags;
1268 	unsigned int ier;
1269 	int locked = 1;
1270 
1271 	pm_runtime_get_sync(up->dev);
1272 
1273 	local_irq_save(flags);
1274 	if (up->port.sysrq)
1275 		locked = 0;
1276 	else if (oops_in_progress)
1277 		locked = spin_trylock(&up->port.lock);
1278 	else
1279 		spin_lock(&up->port.lock);
1280 
1281 	/*
1282 	 * First save the IER then disable the interrupts
1283 	 */
1284 	ier = serial_in(up, UART_IER);
1285 	serial_out(up, UART_IER, 0);
1286 
1287 	uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1288 
1289 	/*
1290 	 * Finally, wait for transmitter to become empty
1291 	 * and restore the IER
1292 	 */
1293 	wait_for_xmitr(up);
1294 	serial_out(up, UART_IER, ier);
1295 	/*
1296 	 * The receive handling will happen properly because the
1297 	 * receive ready bit will still be set; it is not cleared
1298 	 * on read.  However, modem control will not, we must
1299 	 * call it if we have saved something in the saved flags
1300 	 * while processing with interrupts off.
1301 	 */
1302 	if (up->msr_saved_flags)
1303 		check_modem_status(up);
1304 
1305 	pm_runtime_mark_last_busy(up->dev);
1306 	pm_runtime_put_autosuspend(up->dev);
1307 	if (locked)
1308 		spin_unlock(&up->port.lock);
1309 	local_irq_restore(flags);
1310 }
1311 
1312 static int __init
1313 serial_omap_console_setup(struct console *co, char *options)
1314 {
1315 	struct uart_omap_port *up;
1316 	int baud = 115200;
1317 	int bits = 8;
1318 	int parity = 'n';
1319 	int flow = 'n';
1320 
1321 	if (serial_omap_console_ports[co->index] == NULL)
1322 		return -ENODEV;
1323 	up = serial_omap_console_ports[co->index];
1324 
1325 	if (options)
1326 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1327 
1328 	return uart_set_options(&up->port, co, baud, parity, bits, flow);
1329 }
1330 
1331 static struct console serial_omap_console = {
1332 	.name		= OMAP_SERIAL_NAME,
1333 	.write		= serial_omap_console_write,
1334 	.device		= uart_console_device,
1335 	.setup		= serial_omap_console_setup,
1336 	.flags		= CON_PRINTBUFFER,
1337 	.index		= -1,
1338 	.data		= &serial_omap_reg,
1339 };
1340 
1341 static void serial_omap_add_console_port(struct uart_omap_port *up)
1342 {
1343 	serial_omap_console_ports[up->port.line] = up;
1344 }
1345 
1346 #define OMAP_CONSOLE	(&serial_omap_console)
1347 
1348 #else
1349 
1350 #define OMAP_CONSOLE	NULL
1351 
1352 static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1353 {}
1354 
1355 #endif
1356 
1357 /* Enable or disable the rs485 support */
1358 static void
1359 serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
1360 {
1361 	struct uart_omap_port *up = to_uart_omap_port(port);
1362 	unsigned long flags;
1363 	unsigned int mode;
1364 	int val;
1365 
1366 	pm_runtime_get_sync(up->dev);
1367 	spin_lock_irqsave(&up->port.lock, flags);
1368 
1369 	/* Disable interrupts from this port */
1370 	mode = up->ier;
1371 	up->ier = 0;
1372 	serial_out(up, UART_IER, 0);
1373 
1374 	/* store new config */
1375 	up->rs485 = *rs485conf;
1376 
1377 	/*
1378 	 * Just as a precaution, only allow rs485
1379 	 * to be enabled if the gpio pin is valid
1380 	 */
1381 	if (gpio_is_valid(up->rts_gpio)) {
1382 		/* enable / disable rts */
1383 		val = (up->rs485.flags & SER_RS485_ENABLED) ?
1384 			SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
1385 		val = (up->rs485.flags & val) ? 1 : 0;
1386 		gpio_set_value(up->rts_gpio, val);
1387 	} else
1388 		up->rs485.flags &= ~SER_RS485_ENABLED;
1389 
1390 	/* Enable interrupts */
1391 	up->ier = mode;
1392 	serial_out(up, UART_IER, up->ier);
1393 
1394 	/* If RS-485 is disabled, make sure the THR interrupt is fired when
1395 	 * TX FIFO is below the trigger level.
1396 	 */
1397 	if (!(up->rs485.flags & SER_RS485_ENABLED) &&
1398 	    (up->scr & OMAP_UART_SCR_TX_EMPTY)) {
1399 		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
1400 		serial_out(up, UART_OMAP_SCR, up->scr);
1401 	}
1402 
1403 	spin_unlock_irqrestore(&up->port.lock, flags);
1404 	pm_runtime_mark_last_busy(up->dev);
1405 	pm_runtime_put_autosuspend(up->dev);
1406 }
1407 
1408 static int
1409 serial_omap_ioctl(struct uart_port *port, unsigned int cmd, unsigned long arg)
1410 {
1411 	struct serial_rs485 rs485conf;
1412 
1413 	switch (cmd) {
1414 	case TIOCSRS485:
1415 		if (copy_from_user(&rs485conf, (void __user *) arg,
1416 					sizeof(rs485conf)))
1417 			return -EFAULT;
1418 
1419 		serial_omap_config_rs485(port, &rs485conf);
1420 		break;
1421 
1422 	case TIOCGRS485:
1423 		if (copy_to_user((void __user *) arg,
1424 					&(to_uart_omap_port(port)->rs485),
1425 					sizeof(rs485conf)))
1426 			return -EFAULT;
1427 		break;
1428 
1429 	default:
1430 		return -ENOIOCTLCMD;
1431 	}
1432 	return 0;
1433 }
1434 
1435 
1436 static struct uart_ops serial_omap_pops = {
1437 	.tx_empty	= serial_omap_tx_empty,
1438 	.set_mctrl	= serial_omap_set_mctrl,
1439 	.get_mctrl	= serial_omap_get_mctrl,
1440 	.stop_tx	= serial_omap_stop_tx,
1441 	.start_tx	= serial_omap_start_tx,
1442 	.throttle	= serial_omap_throttle,
1443 	.unthrottle	= serial_omap_unthrottle,
1444 	.stop_rx	= serial_omap_stop_rx,
1445 	.enable_ms	= serial_omap_enable_ms,
1446 	.break_ctl	= serial_omap_break_ctl,
1447 	.startup	= serial_omap_startup,
1448 	.shutdown	= serial_omap_shutdown,
1449 	.set_termios	= serial_omap_set_termios,
1450 	.pm		= serial_omap_pm,
1451 	.type		= serial_omap_type,
1452 	.release_port	= serial_omap_release_port,
1453 	.request_port	= serial_omap_request_port,
1454 	.config_port	= serial_omap_config_port,
1455 	.verify_port	= serial_omap_verify_port,
1456 	.ioctl		= serial_omap_ioctl,
1457 #ifdef CONFIG_CONSOLE_POLL
1458 	.poll_put_char  = serial_omap_poll_put_char,
1459 	.poll_get_char  = serial_omap_poll_get_char,
1460 #endif
1461 };
1462 
1463 static struct uart_driver serial_omap_reg = {
1464 	.owner		= THIS_MODULE,
1465 	.driver_name	= "OMAP-SERIAL",
1466 	.dev_name	= OMAP_SERIAL_NAME,
1467 	.nr		= OMAP_MAX_HSUART_PORTS,
1468 	.cons		= OMAP_CONSOLE,
1469 };
1470 
1471 #ifdef CONFIG_PM_SLEEP
1472 static int serial_omap_prepare(struct device *dev)
1473 {
1474 	struct uart_omap_port *up = dev_get_drvdata(dev);
1475 
1476 	up->is_suspending = true;
1477 
1478 	return 0;
1479 }
1480 
1481 static void serial_omap_complete(struct device *dev)
1482 {
1483 	struct uart_omap_port *up = dev_get_drvdata(dev);
1484 
1485 	up->is_suspending = false;
1486 }
1487 
1488 static int serial_omap_suspend(struct device *dev)
1489 {
1490 	struct uart_omap_port *up = dev_get_drvdata(dev);
1491 
1492 	uart_suspend_port(&serial_omap_reg, &up->port);
1493 	flush_work(&up->qos_work);
1494 
1495 	if (device_may_wakeup(dev))
1496 		serial_omap_enable_wakeup(up, true);
1497 	else
1498 		serial_omap_enable_wakeup(up, false);
1499 
1500 	return 0;
1501 }
1502 
1503 static int serial_omap_resume(struct device *dev)
1504 {
1505 	struct uart_omap_port *up = dev_get_drvdata(dev);
1506 
1507 	if (device_may_wakeup(dev))
1508 		serial_omap_enable_wakeup(up, false);
1509 
1510 	uart_resume_port(&serial_omap_reg, &up->port);
1511 
1512 	return 0;
1513 }
1514 #else
1515 #define serial_omap_prepare NULL
1516 #define serial_omap_complete NULL
1517 #endif /* CONFIG_PM_SLEEP */
1518 
1519 static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
1520 {
1521 	u32 mvr, scheme;
1522 	u16 revision, major, minor;
1523 
1524 	mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
1525 
1526 	/* Check revision register scheme */
1527 	scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
1528 
1529 	switch (scheme) {
1530 	case 0: /* Legacy Scheme: OMAP2/3 */
1531 		/* MINOR_REV[0:4], MAJOR_REV[4:7] */
1532 		major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
1533 					OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
1534 		minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
1535 		break;
1536 	case 1:
1537 		/* New Scheme: OMAP4+ */
1538 		/* MINOR_REV[0:5], MAJOR_REV[8:10] */
1539 		major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
1540 					OMAP_UART_MVR_MAJ_SHIFT;
1541 		minor = (mvr & OMAP_UART_MVR_MIN_MASK);
1542 		break;
1543 	default:
1544 		dev_warn(up->dev,
1545 			"Unknown %s revision, defaulting to highest\n",
1546 			up->name);
1547 		/* highest possible revision */
1548 		major = 0xff;
1549 		minor = 0xff;
1550 	}
1551 
1552 	/* normalize revision for the driver */
1553 	revision = UART_BUILD_REVISION(major, minor);
1554 
1555 	switch (revision) {
1556 	case OMAP_UART_REV_46:
1557 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1558 				UART_ERRATA_i291_DMA_FORCEIDLE);
1559 		break;
1560 	case OMAP_UART_REV_52:
1561 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1562 				UART_ERRATA_i291_DMA_FORCEIDLE);
1563 		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1564 		break;
1565 	case OMAP_UART_REV_63:
1566 		up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
1567 		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1568 		break;
1569 	default:
1570 		break;
1571 	}
1572 }
1573 
1574 static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1575 {
1576 	struct omap_uart_port_info *omap_up_info;
1577 
1578 	omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1579 	if (!omap_up_info)
1580 		return NULL; /* out of memory */
1581 
1582 	of_property_read_u32(dev->of_node, "clock-frequency",
1583 					 &omap_up_info->uartclk);
1584 	return omap_up_info;
1585 }
1586 
1587 static int serial_omap_probe_rs485(struct uart_omap_port *up,
1588 				   struct device_node *np)
1589 {
1590 	struct serial_rs485 *rs485conf = &up->rs485;
1591 	u32 rs485_delay[2];
1592 	enum of_gpio_flags flags;
1593 	int ret;
1594 
1595 	rs485conf->flags = 0;
1596 	up->rts_gpio = -EINVAL;
1597 
1598 	if (!np)
1599 		return 0;
1600 
1601 	if (of_property_read_bool(np, "rs485-rts-active-high"))
1602 		rs485conf->flags |= SER_RS485_RTS_ON_SEND;
1603 	else
1604 		rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
1605 
1606 	/* check for tx enable gpio */
1607 	up->rts_gpio = of_get_named_gpio_flags(np, "rts-gpio", 0, &flags);
1608 	if (gpio_is_valid(up->rts_gpio)) {
1609 		ret = devm_gpio_request(up->dev, up->rts_gpio, "omap-serial");
1610 		if (ret < 0)
1611 			return ret;
1612 		ret = gpio_direction_output(up->rts_gpio,
1613 					    flags & SER_RS485_RTS_AFTER_SEND);
1614 		if (ret < 0)
1615 			return ret;
1616 	} else if (up->rts_gpio == -EPROBE_DEFER) {
1617 		return -EPROBE_DEFER;
1618 	} else {
1619 		up->rts_gpio = -EINVAL;
1620 	}
1621 
1622 	if (of_property_read_u32_array(np, "rs485-rts-delay",
1623 				    rs485_delay, 2) == 0) {
1624 		rs485conf->delay_rts_before_send = rs485_delay[0];
1625 		rs485conf->delay_rts_after_send = rs485_delay[1];
1626 	}
1627 
1628 	if (of_property_read_bool(np, "rs485-rx-during-tx"))
1629 		rs485conf->flags |= SER_RS485_RX_DURING_TX;
1630 
1631 	if (of_property_read_bool(np, "linux,rs485-enabled-at-boot-time"))
1632 		rs485conf->flags |= SER_RS485_ENABLED;
1633 
1634 	return 0;
1635 }
1636 
1637 static int serial_omap_probe(struct platform_device *pdev)
1638 {
1639 	struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
1640 	struct uart_omap_port *up;
1641 	struct resource *mem;
1642 	void __iomem *base;
1643 	int uartirq = 0;
1644 	int wakeirq = 0;
1645 	int ret;
1646 
1647 	/* The optional wakeirq may be specified in the board dts file */
1648 	if (pdev->dev.of_node) {
1649 		uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0);
1650 		if (!uartirq)
1651 			return -EPROBE_DEFER;
1652 		wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
1653 		omap_up_info = of_get_uart_port_info(&pdev->dev);
1654 		pdev->dev.platform_data = omap_up_info;
1655 	} else {
1656 		uartirq = platform_get_irq(pdev, 0);
1657 		if (uartirq < 0)
1658 			return -EPROBE_DEFER;
1659 	}
1660 
1661 	up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
1662 	if (!up)
1663 		return -ENOMEM;
1664 
1665 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1666 	base = devm_ioremap_resource(&pdev->dev, mem);
1667 	if (IS_ERR(base))
1668 		return PTR_ERR(base);
1669 
1670 	up->dev = &pdev->dev;
1671 	up->port.dev = &pdev->dev;
1672 	up->port.type = PORT_OMAP;
1673 	up->port.iotype = UPIO_MEM;
1674 	up->port.irq = uartirq;
1675 	up->wakeirq = wakeirq;
1676 	if (!up->wakeirq)
1677 		dev_info(up->port.dev, "no wakeirq for uart%d\n",
1678 			 up->port.line);
1679 
1680 	up->port.regshift = 2;
1681 	up->port.fifosize = 64;
1682 	up->port.ops = &serial_omap_pops;
1683 
1684 	if (pdev->dev.of_node)
1685 		up->port.line = of_alias_get_id(pdev->dev.of_node, "serial");
1686 	else
1687 		up->port.line = pdev->id;
1688 
1689 	if (up->port.line < 0) {
1690 		dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1691 								up->port.line);
1692 		ret = -ENODEV;
1693 		goto err_port_line;
1694 	}
1695 
1696 	ret = serial_omap_probe_rs485(up, pdev->dev.of_node);
1697 	if (ret < 0)
1698 		goto err_rs485;
1699 
1700 	sprintf(up->name, "OMAP UART%d", up->port.line);
1701 	up->port.mapbase = mem->start;
1702 	up->port.membase = base;
1703 	up->port.flags = omap_up_info->flags;
1704 	up->port.uartclk = omap_up_info->uartclk;
1705 	if (!up->port.uartclk) {
1706 		up->port.uartclk = DEFAULT_CLK_SPEED;
1707 		dev_warn(&pdev->dev,
1708 			 "No clock speed specified: using default: %d\n",
1709 			 DEFAULT_CLK_SPEED);
1710 	}
1711 
1712 	up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1713 	up->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1714 	pm_qos_add_request(&up->pm_qos_request,
1715 		PM_QOS_CPU_DMA_LATENCY, up->latency);
1716 	INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1717 
1718 	platform_set_drvdata(pdev, up);
1719 	if (omap_up_info->autosuspend_timeout == 0)
1720 		omap_up_info->autosuspend_timeout = -1;
1721 
1722 	device_init_wakeup(up->dev, true);
1723 	pm_runtime_use_autosuspend(&pdev->dev);
1724 	pm_runtime_set_autosuspend_delay(&pdev->dev,
1725 			omap_up_info->autosuspend_timeout);
1726 
1727 	pm_runtime_irq_safe(&pdev->dev);
1728 	pm_runtime_enable(&pdev->dev);
1729 
1730 	pm_runtime_get_sync(&pdev->dev);
1731 
1732 	omap_serial_fill_features_erratas(up);
1733 
1734 	ui[up->port.line] = up;
1735 	serial_omap_add_console_port(up);
1736 
1737 	ret = uart_add_one_port(&serial_omap_reg, &up->port);
1738 	if (ret != 0)
1739 		goto err_add_port;
1740 
1741 	pm_runtime_mark_last_busy(up->dev);
1742 	pm_runtime_put_autosuspend(up->dev);
1743 	return 0;
1744 
1745 err_add_port:
1746 	pm_runtime_put(&pdev->dev);
1747 	pm_runtime_disable(&pdev->dev);
1748 err_rs485:
1749 err_port_line:
1750 	dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n",
1751 				pdev->id, __func__, ret);
1752 	return ret;
1753 }
1754 
1755 static int serial_omap_remove(struct platform_device *dev)
1756 {
1757 	struct uart_omap_port *up = platform_get_drvdata(dev);
1758 
1759 	pm_runtime_put_sync(up->dev);
1760 	pm_runtime_disable(up->dev);
1761 	uart_remove_one_port(&serial_omap_reg, &up->port);
1762 	pm_qos_remove_request(&up->pm_qos_request);
1763 	device_init_wakeup(&dev->dev, false);
1764 
1765 	return 0;
1766 }
1767 
1768 /*
1769  * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1770  * The access to uart register after MDR1 Access
1771  * causes UART to corrupt data.
1772  *
1773  * Need a delay =
1774  * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1775  * give 10 times as much
1776  */
1777 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1778 {
1779 	u8 timeout = 255;
1780 
1781 	serial_out(up, UART_OMAP_MDR1, mdr1);
1782 	udelay(2);
1783 	serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1784 			UART_FCR_CLEAR_RCVR);
1785 	/*
1786 	 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1787 	 * TX_FIFO_E bit is 1.
1788 	 */
1789 	while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1790 				(UART_LSR_THRE | UART_LSR_DR))) {
1791 		timeout--;
1792 		if (!timeout) {
1793 			/* Should *never* happen. we warn and carry on */
1794 			dev_crit(up->dev, "Errata i202: timedout %x\n",
1795 						serial_in(up, UART_LSR));
1796 			break;
1797 		}
1798 		udelay(1);
1799 	}
1800 }
1801 
1802 #ifdef CONFIG_PM_RUNTIME
1803 static void serial_omap_restore_context(struct uart_omap_port *up)
1804 {
1805 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1806 		serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1807 	else
1808 		serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1809 
1810 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1811 	serial_out(up, UART_EFR, UART_EFR_ECB);
1812 	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1813 	serial_out(up, UART_IER, 0x0);
1814 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1815 	serial_out(up, UART_DLL, up->dll);
1816 	serial_out(up, UART_DLM, up->dlh);
1817 	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1818 	serial_out(up, UART_IER, up->ier);
1819 	serial_out(up, UART_FCR, up->fcr);
1820 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1821 	serial_out(up, UART_MCR, up->mcr);
1822 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1823 	serial_out(up, UART_OMAP_SCR, up->scr);
1824 	serial_out(up, UART_EFR, up->efr);
1825 	serial_out(up, UART_LCR, up->lcr);
1826 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1827 		serial_omap_mdr1_errataset(up, up->mdr1);
1828 	else
1829 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1830 	serial_out(up, UART_OMAP_WER, up->wer);
1831 }
1832 
1833 static int serial_omap_runtime_suspend(struct device *dev)
1834 {
1835 	struct uart_omap_port *up = dev_get_drvdata(dev);
1836 
1837 	if (!up)
1838 		return -EINVAL;
1839 
1840 	/*
1841 	* When using 'no_console_suspend', the console UART must not be
1842 	* suspended. Since driver suspend is managed by runtime suspend,
1843 	* preventing runtime suspend (by returning error) will keep device
1844 	* active during suspend.
1845 	*/
1846 	if (up->is_suspending && !console_suspend_enabled &&
1847 	    uart_console(&up->port))
1848 		return -EBUSY;
1849 
1850 	up->context_loss_cnt = serial_omap_get_context_loss_count(up);
1851 
1852 	serial_omap_enable_wakeup(up, true);
1853 
1854 	up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1855 	schedule_work(&up->qos_work);
1856 
1857 	return 0;
1858 }
1859 
1860 static int serial_omap_runtime_resume(struct device *dev)
1861 {
1862 	struct uart_omap_port *up = dev_get_drvdata(dev);
1863 
1864 	int loss_cnt = serial_omap_get_context_loss_count(up);
1865 
1866 	serial_omap_enable_wakeup(up, false);
1867 
1868 	if (loss_cnt < 0) {
1869 		dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
1870 			loss_cnt);
1871 		serial_omap_restore_context(up);
1872 	} else if (up->context_loss_cnt != loss_cnt) {
1873 		serial_omap_restore_context(up);
1874 	}
1875 	up->latency = up->calc_latency;
1876 	schedule_work(&up->qos_work);
1877 
1878 	return 0;
1879 }
1880 #endif
1881 
1882 static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1883 	SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1884 	SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1885 				serial_omap_runtime_resume, NULL)
1886 	.prepare        = serial_omap_prepare,
1887 	.complete       = serial_omap_complete,
1888 };
1889 
1890 #if defined(CONFIG_OF)
1891 static const struct of_device_id omap_serial_of_match[] = {
1892 	{ .compatible = "ti,omap2-uart" },
1893 	{ .compatible = "ti,omap3-uart" },
1894 	{ .compatible = "ti,omap4-uart" },
1895 	{},
1896 };
1897 MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1898 #endif
1899 
1900 static struct platform_driver serial_omap_driver = {
1901 	.probe          = serial_omap_probe,
1902 	.remove         = serial_omap_remove,
1903 	.driver		= {
1904 		.name	= DRIVER_NAME,
1905 		.pm	= &serial_omap_dev_pm_ops,
1906 		.of_match_table = of_match_ptr(omap_serial_of_match),
1907 	},
1908 };
1909 
1910 static int __init serial_omap_init(void)
1911 {
1912 	int ret;
1913 
1914 	ret = uart_register_driver(&serial_omap_reg);
1915 	if (ret != 0)
1916 		return ret;
1917 	ret = platform_driver_register(&serial_omap_driver);
1918 	if (ret != 0)
1919 		uart_unregister_driver(&serial_omap_reg);
1920 	return ret;
1921 }
1922 
1923 static void __exit serial_omap_exit(void)
1924 {
1925 	platform_driver_unregister(&serial_omap_driver);
1926 	uart_unregister_driver(&serial_omap_reg);
1927 }
1928 
1929 module_init(serial_omap_init);
1930 module_exit(serial_omap_exit);
1931 
1932 MODULE_DESCRIPTION("OMAP High Speed UART driver");
1933 MODULE_LICENSE("GPL");
1934 MODULE_AUTHOR("Texas Instruments Inc");
1935