xref: /linux/drivers/tty/serial/omap-serial.c (revision 4b3c1f1b15f576445c221cbc77a88540433a2ba7)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Driver for OMAP-UART controller.
4  * Based on drivers/serial/8250.c
5  *
6  * Copyright (C) 2010 Texas Instruments.
7  *
8  * Authors:
9  *	Govindraj R	<govindraj.raja@ti.com>
10  *	Thara Gopinath	<thara@ti.com>
11  *
12  * Note: This driver is made separate from 8250 driver as we cannot
13  * over load 8250 driver with omap platform specific configuration for
14  * features like DMA, it makes easier to implement features like DMA and
15  * hardware flow control and software flow control configuration with
16  * this driver as required for the omap-platform.
17  */
18 
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/console.h>
22 #include <linux/serial_reg.h>
23 #include <linux/delay.h>
24 #include <linux/slab.h>
25 #include <linux/tty.h>
26 #include <linux/tty_flip.h>
27 #include <linux/platform_device.h>
28 #include <linux/io.h>
29 #include <linux/clk.h>
30 #include <linux/serial_core.h>
31 #include <linux/irq.h>
32 #include <linux/pm_runtime.h>
33 #include <linux/pm_wakeirq.h>
34 #include <linux/of.h>
35 #include <linux/of_irq.h>
36 #include <linux/gpio/consumer.h>
37 #include <linux/platform_data/serial-omap.h>
38 
39 #define OMAP_MAX_HSUART_PORTS	10
40 
41 #define UART_BUILD_REVISION(x, y)	(((x) << 8) | (y))
42 
43 #define OMAP_UART_REV_42 0x0402
44 #define OMAP_UART_REV_46 0x0406
45 #define OMAP_UART_REV_52 0x0502
46 #define OMAP_UART_REV_63 0x0603
47 
48 #define OMAP_UART_TX_WAKEUP_EN		BIT(7)
49 
50 /* Feature flags */
51 #define OMAP_UART_WER_HAS_TX_WAKEUP	BIT(0)
52 
53 #define UART_ERRATA_i202_MDR1_ACCESS	BIT(0)
54 #define UART_ERRATA_i291_DMA_FORCEIDLE	BIT(1)
55 
56 #define DEFAULT_CLK_SPEED 48000000 /* 48Mhz */
57 
58 /* SCR register bitmasks */
59 #define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK		(1 << 7)
60 #define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK		(1 << 6)
61 #define OMAP_UART_SCR_TX_EMPTY			(1 << 3)
62 
63 /* FCR register bitmasks */
64 #define OMAP_UART_FCR_RX_FIFO_TRIG_MASK			(0x3 << 6)
65 #define OMAP_UART_FCR_TX_FIFO_TRIG_MASK			(0x3 << 4)
66 
67 /* MVR register bitmasks */
68 #define OMAP_UART_MVR_SCHEME_SHIFT	30
69 
70 #define OMAP_UART_LEGACY_MVR_MAJ_MASK	0xf0
71 #define OMAP_UART_LEGACY_MVR_MAJ_SHIFT	4
72 #define OMAP_UART_LEGACY_MVR_MIN_MASK	0x0f
73 
74 #define OMAP_UART_MVR_MAJ_MASK		0x700
75 #define OMAP_UART_MVR_MAJ_SHIFT		8
76 #define OMAP_UART_MVR_MIN_MASK		0x3f
77 
78 #define OMAP_UART_DMA_CH_FREE	-1
79 
80 #define MSR_SAVE_FLAGS		UART_MSR_ANY_DELTA
81 #define OMAP_MODE13X_SPEED	230400
82 
83 /* WER = 0x7F
84  * Enable module level wakeup in WER reg
85  */
86 #define OMAP_UART_WER_MOD_WKUP	0x7F
87 
88 /* Enable XON/XOFF flow control on output */
89 #define OMAP_UART_SW_TX		0x08
90 
91 /* Enable XON/XOFF flow control on input */
92 #define OMAP_UART_SW_RX		0x02
93 
94 #define OMAP_UART_SW_CLR	0xF0
95 
96 #define OMAP_UART_TCR_TRIG	0x0F
97 
98 struct uart_omap_dma {
99 	u8			uart_dma_tx;
100 	u8			uart_dma_rx;
101 	int			rx_dma_channel;
102 	int			tx_dma_channel;
103 	dma_addr_t		rx_buf_dma_phys;
104 	dma_addr_t		tx_buf_dma_phys;
105 	unsigned int		uart_base;
106 	/*
107 	 * Buffer for rx dma. It is not required for tx because the buffer
108 	 * comes from port structure.
109 	 */
110 	unsigned char		*rx_buf;
111 	unsigned int		prev_rx_dma_pos;
112 	int			tx_buf_size;
113 	int			tx_dma_used;
114 	int			rx_dma_used;
115 	spinlock_t		tx_lock;
116 	spinlock_t		rx_lock;
117 	/* timer to poll activity on rx dma */
118 	struct timer_list	rx_timer;
119 	unsigned int		rx_buf_size;
120 	unsigned int		rx_poll_rate;
121 	unsigned int		rx_timeout;
122 };
123 
124 struct uart_omap_port {
125 	struct uart_port	port;
126 	struct uart_omap_dma	uart_dma;
127 	struct device		*dev;
128 	int			wakeirq;
129 
130 	unsigned char		ier;
131 	unsigned char		lcr;
132 	unsigned char		mcr;
133 	unsigned char		fcr;
134 	unsigned char		efr;
135 	unsigned char		dll;
136 	unsigned char		dlh;
137 	unsigned char		mdr1;
138 	unsigned char		scr;
139 	unsigned char		wer;
140 
141 	int			use_dma;
142 	/*
143 	 * Some bits in registers are cleared on a read, so they must
144 	 * be saved whenever the register is read, but the bits will not
145 	 * be immediately processed.
146 	 */
147 	unsigned int		lsr_break_flag;
148 	unsigned char		msr_saved_flags;
149 	char			name[20];
150 	unsigned long		port_activity;
151 	int			context_loss_cnt;
152 	u32			errata;
153 	u32			features;
154 
155 	struct gpio_desc	*rts_gpiod;
156 
157 	struct pm_qos_request	pm_qos_request;
158 	u32			latency;
159 	u32			calc_latency;
160 	struct work_struct	qos_work;
161 	bool			is_suspending;
162 };
163 
164 #define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
165 
166 static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
167 
168 /* Forward declaration of functions */
169 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
170 
171 static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
172 {
173 	offset <<= up->port.regshift;
174 	return readw(up->port.membase + offset);
175 }
176 
177 static inline void serial_out(struct uart_omap_port *up, int offset, int value)
178 {
179 	offset <<= up->port.regshift;
180 	writew(value, up->port.membase + offset);
181 }
182 
183 static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
184 {
185 	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
186 	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
187 		       UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
188 	serial_out(up, UART_FCR, 0);
189 }
190 
191 #ifdef CONFIG_PM
192 static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
193 {
194 	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
195 
196 	if (!pdata || !pdata->get_context_loss_count)
197 		return -EINVAL;
198 
199 	return pdata->get_context_loss_count(up->dev);
200 }
201 
202 /* REVISIT: Remove this when omap3 boots in device tree only mode */
203 static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
204 {
205 	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
206 
207 	if (!pdata || !pdata->enable_wakeup)
208 		return;
209 
210 	pdata->enable_wakeup(up->dev, enable);
211 }
212 #endif /* CONFIG_PM */
213 
214 /*
215  * Calculate the absolute difference between the desired and actual baud
216  * rate for the given mode.
217  */
218 static inline int calculate_baud_abs_diff(struct uart_port *port,
219 				unsigned int baud, unsigned int mode)
220 {
221 	unsigned int n = port->uartclk / (mode * baud);
222 	int abs_diff;
223 
224 	if (n == 0)
225 		n = 1;
226 
227 	abs_diff = baud - (port->uartclk / (mode * n));
228 	if (abs_diff < 0)
229 		abs_diff = -abs_diff;
230 
231 	return abs_diff;
232 }
233 
234 /*
235  * serial_omap_baud_is_mode16 - check if baud rate is MODE16X
236  * @port: uart port info
237  * @baud: baudrate for which mode needs to be determined
238  *
239  * Returns true if baud rate is MODE16X and false if MODE13X
240  * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
241  * and Error Rates" determines modes not for all common baud rates.
242  * E.g. for 1000000 baud rate mode must be 16x, but according to that
243  * table it's determined as 13x.
244  */
245 static bool
246 serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
247 {
248 	int abs_diff_13 = calculate_baud_abs_diff(port, baud, 13);
249 	int abs_diff_16 = calculate_baud_abs_diff(port, baud, 16);
250 
251 	return (abs_diff_13 >= abs_diff_16);
252 }
253 
254 /*
255  * serial_omap_get_divisor - calculate divisor value
256  * @port: uart port info
257  * @baud: baudrate for which divisor needs to be calculated.
258  */
259 static unsigned int
260 serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
261 {
262 	unsigned int mode;
263 
264 	if (!serial_omap_baud_is_mode16(port, baud))
265 		mode = 13;
266 	else
267 		mode = 16;
268 	return port->uartclk/(mode * baud);
269 }
270 
271 static void serial_omap_enable_ms(struct uart_port *port)
272 {
273 	struct uart_omap_port *up = to_uart_omap_port(port);
274 
275 	dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
276 
277 	pm_runtime_get_sync(up->dev);
278 	up->ier |= UART_IER_MSI;
279 	serial_out(up, UART_IER, up->ier);
280 	pm_runtime_mark_last_busy(up->dev);
281 	pm_runtime_put_autosuspend(up->dev);
282 }
283 
284 static void serial_omap_stop_tx(struct uart_port *port)
285 {
286 	struct uart_omap_port *up = to_uart_omap_port(port);
287 	int res;
288 
289 	pm_runtime_get_sync(up->dev);
290 
291 	/* Handle RS-485 */
292 	if (port->rs485.flags & SER_RS485_ENABLED) {
293 		if (up->scr & OMAP_UART_SCR_TX_EMPTY) {
294 			/* THR interrupt is fired when both TX FIFO and TX
295 			 * shift register are empty. This means there's nothing
296 			 * left to transmit now, so make sure the THR interrupt
297 			 * is fired when TX FIFO is below the trigger level,
298 			 * disable THR interrupts and toggle the RS-485 GPIO
299 			 * data direction pin if needed.
300 			 */
301 			up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
302 			serial_out(up, UART_OMAP_SCR, up->scr);
303 			res = (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) ?
304 				1 : 0;
305 			if (gpiod_get_value(up->rts_gpiod) != res) {
306 				if (port->rs485.delay_rts_after_send > 0)
307 					mdelay(
308 					port->rs485.delay_rts_after_send);
309 				gpiod_set_value(up->rts_gpiod, res);
310 			}
311 		} else {
312 			/* We're asked to stop, but there's still stuff in the
313 			 * UART FIFO, so make sure the THR interrupt is fired
314 			 * when both TX FIFO and TX shift register are empty.
315 			 * The next THR interrupt (if no transmission is started
316 			 * in the meantime) will indicate the end of a
317 			 * transmission. Therefore we _don't_ disable THR
318 			 * interrupts in this situation.
319 			 */
320 			up->scr |= OMAP_UART_SCR_TX_EMPTY;
321 			serial_out(up, UART_OMAP_SCR, up->scr);
322 			return;
323 		}
324 	}
325 
326 	if (up->ier & UART_IER_THRI) {
327 		up->ier &= ~UART_IER_THRI;
328 		serial_out(up, UART_IER, up->ier);
329 	}
330 
331 	if ((port->rs485.flags & SER_RS485_ENABLED) &&
332 	    !(port->rs485.flags & SER_RS485_RX_DURING_TX)) {
333 		/*
334 		 * Empty the RX FIFO, we are not interested in anything
335 		 * received during the half-duplex transmission.
336 		 */
337 		serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_RCVR);
338 		/* Re-enable RX interrupts */
339 		up->ier |= UART_IER_RLSI | UART_IER_RDI;
340 		up->port.read_status_mask |= UART_LSR_DR;
341 		serial_out(up, UART_IER, up->ier);
342 	}
343 
344 	pm_runtime_mark_last_busy(up->dev);
345 	pm_runtime_put_autosuspend(up->dev);
346 }
347 
348 static void serial_omap_stop_rx(struct uart_port *port)
349 {
350 	struct uart_omap_port *up = to_uart_omap_port(port);
351 
352 	pm_runtime_get_sync(up->dev);
353 	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
354 	up->port.read_status_mask &= ~UART_LSR_DR;
355 	serial_out(up, UART_IER, up->ier);
356 	pm_runtime_mark_last_busy(up->dev);
357 	pm_runtime_put_autosuspend(up->dev);
358 }
359 
360 static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
361 {
362 	struct circ_buf *xmit = &up->port.state->xmit;
363 	int count;
364 
365 	if (up->port.x_char) {
366 		serial_out(up, UART_TX, up->port.x_char);
367 		up->port.icount.tx++;
368 		up->port.x_char = 0;
369 		return;
370 	}
371 	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
372 		serial_omap_stop_tx(&up->port);
373 		return;
374 	}
375 	count = up->port.fifosize / 4;
376 	do {
377 		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
378 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
379 		up->port.icount.tx++;
380 		if (uart_circ_empty(xmit))
381 			break;
382 	} while (--count > 0);
383 
384 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
385 		uart_write_wakeup(&up->port);
386 
387 	if (uart_circ_empty(xmit))
388 		serial_omap_stop_tx(&up->port);
389 }
390 
391 static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
392 {
393 	if (!(up->ier & UART_IER_THRI)) {
394 		up->ier |= UART_IER_THRI;
395 		serial_out(up, UART_IER, up->ier);
396 	}
397 }
398 
399 static void serial_omap_start_tx(struct uart_port *port)
400 {
401 	struct uart_omap_port *up = to_uart_omap_port(port);
402 	int res;
403 
404 	pm_runtime_get_sync(up->dev);
405 
406 	/* Handle RS-485 */
407 	if (port->rs485.flags & SER_RS485_ENABLED) {
408 		/* Fire THR interrupts when FIFO is below trigger level */
409 		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
410 		serial_out(up, UART_OMAP_SCR, up->scr);
411 
412 		/* if rts not already enabled */
413 		res = (port->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
414 		if (gpiod_get_value(up->rts_gpiod) != res) {
415 			gpiod_set_value(up->rts_gpiod, res);
416 			if (port->rs485.delay_rts_before_send > 0)
417 				mdelay(port->rs485.delay_rts_before_send);
418 		}
419 	}
420 
421 	if ((port->rs485.flags & SER_RS485_ENABLED) &&
422 	    !(port->rs485.flags & SER_RS485_RX_DURING_TX))
423 		serial_omap_stop_rx(port);
424 
425 	serial_omap_enable_ier_thri(up);
426 	pm_runtime_mark_last_busy(up->dev);
427 	pm_runtime_put_autosuspend(up->dev);
428 }
429 
430 static void serial_omap_throttle(struct uart_port *port)
431 {
432 	struct uart_omap_port *up = to_uart_omap_port(port);
433 	unsigned long flags;
434 
435 	pm_runtime_get_sync(up->dev);
436 	spin_lock_irqsave(&up->port.lock, flags);
437 	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
438 	serial_out(up, UART_IER, up->ier);
439 	spin_unlock_irqrestore(&up->port.lock, flags);
440 	pm_runtime_mark_last_busy(up->dev);
441 	pm_runtime_put_autosuspend(up->dev);
442 }
443 
444 static void serial_omap_unthrottle(struct uart_port *port)
445 {
446 	struct uart_omap_port *up = to_uart_omap_port(port);
447 	unsigned long flags;
448 
449 	pm_runtime_get_sync(up->dev);
450 	spin_lock_irqsave(&up->port.lock, flags);
451 	up->ier |= UART_IER_RLSI | UART_IER_RDI;
452 	serial_out(up, UART_IER, up->ier);
453 	spin_unlock_irqrestore(&up->port.lock, flags);
454 	pm_runtime_mark_last_busy(up->dev);
455 	pm_runtime_put_autosuspend(up->dev);
456 }
457 
458 static unsigned int check_modem_status(struct uart_omap_port *up)
459 {
460 	unsigned int status;
461 
462 	status = serial_in(up, UART_MSR);
463 	status |= up->msr_saved_flags;
464 	up->msr_saved_flags = 0;
465 	if ((status & UART_MSR_ANY_DELTA) == 0)
466 		return status;
467 
468 	if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
469 	    up->port.state != NULL) {
470 		if (status & UART_MSR_TERI)
471 			up->port.icount.rng++;
472 		if (status & UART_MSR_DDSR)
473 			up->port.icount.dsr++;
474 		if (status & UART_MSR_DDCD)
475 			uart_handle_dcd_change
476 				(&up->port, status & UART_MSR_DCD);
477 		if (status & UART_MSR_DCTS)
478 			uart_handle_cts_change
479 				(&up->port, status & UART_MSR_CTS);
480 		wake_up_interruptible(&up->port.state->port.delta_msr_wait);
481 	}
482 
483 	return status;
484 }
485 
486 static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
487 {
488 	unsigned int flag;
489 
490 	/*
491 	 * Read one data character out to avoid stalling the receiver according
492 	 * to the table 23-246 of the omap4 TRM.
493 	 */
494 	if (likely(lsr & UART_LSR_DR))
495 		serial_in(up, UART_RX);
496 
497 	up->port.icount.rx++;
498 	flag = TTY_NORMAL;
499 
500 	if (lsr & UART_LSR_BI) {
501 		flag = TTY_BREAK;
502 		lsr &= ~(UART_LSR_FE | UART_LSR_PE);
503 		up->port.icount.brk++;
504 		/*
505 		 * We do the SysRQ and SAK checking
506 		 * here because otherwise the break
507 		 * may get masked by ignore_status_mask
508 		 * or read_status_mask.
509 		 */
510 		if (uart_handle_break(&up->port))
511 			return;
512 
513 	}
514 
515 	if (lsr & UART_LSR_PE) {
516 		flag = TTY_PARITY;
517 		up->port.icount.parity++;
518 	}
519 
520 	if (lsr & UART_LSR_FE) {
521 		flag = TTY_FRAME;
522 		up->port.icount.frame++;
523 	}
524 
525 	if (lsr & UART_LSR_OE)
526 		up->port.icount.overrun++;
527 
528 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
529 	if (up->port.line == up->port.cons->index) {
530 		/* Recover the break flag from console xmit */
531 		lsr |= up->lsr_break_flag;
532 	}
533 #endif
534 	uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag);
535 }
536 
537 static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
538 {
539 	unsigned char ch = 0;
540 	unsigned int flag;
541 
542 	if (!(lsr & UART_LSR_DR))
543 		return;
544 
545 	ch = serial_in(up, UART_RX);
546 	flag = TTY_NORMAL;
547 	up->port.icount.rx++;
548 
549 	if (uart_handle_sysrq_char(&up->port, ch))
550 		return;
551 
552 	uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
553 }
554 
555 /**
556  * serial_omap_irq() - This handles the interrupt from one port
557  * @irq: uart port irq number
558  * @dev_id: uart port info
559  */
560 static irqreturn_t serial_omap_irq(int irq, void *dev_id)
561 {
562 	struct uart_omap_port *up = dev_id;
563 	unsigned int iir, lsr;
564 	unsigned int type;
565 	irqreturn_t ret = IRQ_NONE;
566 	int max_count = 256;
567 
568 	spin_lock(&up->port.lock);
569 	pm_runtime_get_sync(up->dev);
570 
571 	do {
572 		iir = serial_in(up, UART_IIR);
573 		if (iir & UART_IIR_NO_INT)
574 			break;
575 
576 		ret = IRQ_HANDLED;
577 		lsr = serial_in(up, UART_LSR);
578 
579 		/* extract IRQ type from IIR register */
580 		type = iir & 0x3e;
581 
582 		switch (type) {
583 		case UART_IIR_MSI:
584 			check_modem_status(up);
585 			break;
586 		case UART_IIR_THRI:
587 			transmit_chars(up, lsr);
588 			break;
589 		case UART_IIR_RX_TIMEOUT:
590 			/* FALLTHROUGH */
591 		case UART_IIR_RDI:
592 			serial_omap_rdi(up, lsr);
593 			break;
594 		case UART_IIR_RLSI:
595 			serial_omap_rlsi(up, lsr);
596 			break;
597 		case UART_IIR_CTS_RTS_DSR:
598 			/* simply try again */
599 			break;
600 		case UART_IIR_XOFF:
601 			/* FALLTHROUGH */
602 		default:
603 			break;
604 		}
605 	} while (max_count--);
606 
607 	spin_unlock(&up->port.lock);
608 
609 	tty_flip_buffer_push(&up->port.state->port);
610 
611 	pm_runtime_mark_last_busy(up->dev);
612 	pm_runtime_put_autosuspend(up->dev);
613 	up->port_activity = jiffies;
614 
615 	return ret;
616 }
617 
618 static unsigned int serial_omap_tx_empty(struct uart_port *port)
619 {
620 	struct uart_omap_port *up = to_uart_omap_port(port);
621 	unsigned long flags = 0;
622 	unsigned int ret = 0;
623 
624 	pm_runtime_get_sync(up->dev);
625 	dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
626 	spin_lock_irqsave(&up->port.lock, flags);
627 	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
628 	spin_unlock_irqrestore(&up->port.lock, flags);
629 	pm_runtime_mark_last_busy(up->dev);
630 	pm_runtime_put_autosuspend(up->dev);
631 	return ret;
632 }
633 
634 static unsigned int serial_omap_get_mctrl(struct uart_port *port)
635 {
636 	struct uart_omap_port *up = to_uart_omap_port(port);
637 	unsigned int status;
638 	unsigned int ret = 0;
639 
640 	pm_runtime_get_sync(up->dev);
641 	status = check_modem_status(up);
642 	pm_runtime_mark_last_busy(up->dev);
643 	pm_runtime_put_autosuspend(up->dev);
644 
645 	dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
646 
647 	if (status & UART_MSR_DCD)
648 		ret |= TIOCM_CAR;
649 	if (status & UART_MSR_RI)
650 		ret |= TIOCM_RNG;
651 	if (status & UART_MSR_DSR)
652 		ret |= TIOCM_DSR;
653 	if (status & UART_MSR_CTS)
654 		ret |= TIOCM_CTS;
655 	return ret;
656 }
657 
658 static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
659 {
660 	struct uart_omap_port *up = to_uart_omap_port(port);
661 	unsigned char mcr = 0, old_mcr, lcr;
662 
663 	dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
664 	if (mctrl & TIOCM_RTS)
665 		mcr |= UART_MCR_RTS;
666 	if (mctrl & TIOCM_DTR)
667 		mcr |= UART_MCR_DTR;
668 	if (mctrl & TIOCM_OUT1)
669 		mcr |= UART_MCR_OUT1;
670 	if (mctrl & TIOCM_OUT2)
671 		mcr |= UART_MCR_OUT2;
672 	if (mctrl & TIOCM_LOOP)
673 		mcr |= UART_MCR_LOOP;
674 
675 	pm_runtime_get_sync(up->dev);
676 	old_mcr = serial_in(up, UART_MCR);
677 	old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
678 		     UART_MCR_DTR | UART_MCR_RTS);
679 	up->mcr = old_mcr | mcr;
680 	serial_out(up, UART_MCR, up->mcr);
681 
682 	/* Turn off autoRTS if RTS is lowered; restore autoRTS if RTS raised */
683 	lcr = serial_in(up, UART_LCR);
684 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
685 	if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS))
686 		up->efr |= UART_EFR_RTS;
687 	else
688 		up->efr &= ~UART_EFR_RTS;
689 	serial_out(up, UART_EFR, up->efr);
690 	serial_out(up, UART_LCR, lcr);
691 
692 	pm_runtime_mark_last_busy(up->dev);
693 	pm_runtime_put_autosuspend(up->dev);
694 }
695 
696 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
697 {
698 	struct uart_omap_port *up = to_uart_omap_port(port);
699 	unsigned long flags = 0;
700 
701 	dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
702 	pm_runtime_get_sync(up->dev);
703 	spin_lock_irqsave(&up->port.lock, flags);
704 	if (break_state == -1)
705 		up->lcr |= UART_LCR_SBC;
706 	else
707 		up->lcr &= ~UART_LCR_SBC;
708 	serial_out(up, UART_LCR, up->lcr);
709 	spin_unlock_irqrestore(&up->port.lock, flags);
710 	pm_runtime_mark_last_busy(up->dev);
711 	pm_runtime_put_autosuspend(up->dev);
712 }
713 
714 static int serial_omap_startup(struct uart_port *port)
715 {
716 	struct uart_omap_port *up = to_uart_omap_port(port);
717 	unsigned long flags = 0;
718 	int retval;
719 
720 	/*
721 	 * Allocate the IRQ
722 	 */
723 	retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
724 				up->name, up);
725 	if (retval)
726 		return retval;
727 
728 	/* Optional wake-up IRQ */
729 	if (up->wakeirq) {
730 		retval = dev_pm_set_dedicated_wake_irq(up->dev, up->wakeirq);
731 		if (retval) {
732 			free_irq(up->port.irq, up);
733 			return retval;
734 		}
735 	}
736 
737 	dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
738 
739 	pm_runtime_get_sync(up->dev);
740 	/*
741 	 * Clear the FIFO buffers and disable them.
742 	 * (they will be reenabled in set_termios())
743 	 */
744 	serial_omap_clear_fifos(up);
745 
746 	/*
747 	 * Clear the interrupt registers.
748 	 */
749 	(void) serial_in(up, UART_LSR);
750 	if (serial_in(up, UART_LSR) & UART_LSR_DR)
751 		(void) serial_in(up, UART_RX);
752 	(void) serial_in(up, UART_IIR);
753 	(void) serial_in(up, UART_MSR);
754 
755 	/*
756 	 * Now, initialize the UART
757 	 */
758 	serial_out(up, UART_LCR, UART_LCR_WLEN8);
759 	spin_lock_irqsave(&up->port.lock, flags);
760 	/*
761 	 * Most PC uarts need OUT2 raised to enable interrupts.
762 	 */
763 	up->port.mctrl |= TIOCM_OUT2;
764 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
765 	spin_unlock_irqrestore(&up->port.lock, flags);
766 
767 	up->msr_saved_flags = 0;
768 	/*
769 	 * Finally, enable interrupts. Note: Modem status interrupts
770 	 * are set via set_termios(), which will be occurring imminently
771 	 * anyway, so we don't enable them here.
772 	 */
773 	up->ier = UART_IER_RLSI | UART_IER_RDI;
774 	serial_out(up, UART_IER, up->ier);
775 
776 	/* Enable module level wake up */
777 	up->wer = OMAP_UART_WER_MOD_WKUP;
778 	if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
779 		up->wer |= OMAP_UART_TX_WAKEUP_EN;
780 
781 	serial_out(up, UART_OMAP_WER, up->wer);
782 
783 	pm_runtime_mark_last_busy(up->dev);
784 	pm_runtime_put_autosuspend(up->dev);
785 	up->port_activity = jiffies;
786 	return 0;
787 }
788 
789 static void serial_omap_shutdown(struct uart_port *port)
790 {
791 	struct uart_omap_port *up = to_uart_omap_port(port);
792 	unsigned long flags = 0;
793 
794 	dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
795 
796 	pm_runtime_get_sync(up->dev);
797 	/*
798 	 * Disable interrupts from this port
799 	 */
800 	up->ier = 0;
801 	serial_out(up, UART_IER, 0);
802 
803 	spin_lock_irqsave(&up->port.lock, flags);
804 	up->port.mctrl &= ~TIOCM_OUT2;
805 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
806 	spin_unlock_irqrestore(&up->port.lock, flags);
807 
808 	/*
809 	 * Disable break condition and FIFOs
810 	 */
811 	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
812 	serial_omap_clear_fifos(up);
813 
814 	/*
815 	 * Read data port to reset things, and then free the irq
816 	 */
817 	if (serial_in(up, UART_LSR) & UART_LSR_DR)
818 		(void) serial_in(up, UART_RX);
819 
820 	pm_runtime_mark_last_busy(up->dev);
821 	pm_runtime_put_autosuspend(up->dev);
822 	free_irq(up->port.irq, up);
823 	dev_pm_clear_wake_irq(up->dev);
824 }
825 
826 static void serial_omap_uart_qos_work(struct work_struct *work)
827 {
828 	struct uart_omap_port *up = container_of(work, struct uart_omap_port,
829 						qos_work);
830 
831 	cpu_latency_qos_update_request(&up->pm_qos_request, up->latency);
832 }
833 
834 static void
835 serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
836 			struct ktermios *old)
837 {
838 	struct uart_omap_port *up = to_uart_omap_port(port);
839 	unsigned char cval = 0;
840 	unsigned long flags = 0;
841 	unsigned int baud, quot;
842 
843 	switch (termios->c_cflag & CSIZE) {
844 	case CS5:
845 		cval = UART_LCR_WLEN5;
846 		break;
847 	case CS6:
848 		cval = UART_LCR_WLEN6;
849 		break;
850 	case CS7:
851 		cval = UART_LCR_WLEN7;
852 		break;
853 	default:
854 	case CS8:
855 		cval = UART_LCR_WLEN8;
856 		break;
857 	}
858 
859 	if (termios->c_cflag & CSTOPB)
860 		cval |= UART_LCR_STOP;
861 	if (termios->c_cflag & PARENB)
862 		cval |= UART_LCR_PARITY;
863 	if (!(termios->c_cflag & PARODD))
864 		cval |= UART_LCR_EPAR;
865 	if (termios->c_cflag & CMSPAR)
866 		cval |= UART_LCR_SPAR;
867 
868 	/*
869 	 * Ask the core to calculate the divisor for us.
870 	 */
871 
872 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
873 	quot = serial_omap_get_divisor(port, baud);
874 
875 	/* calculate wakeup latency constraint */
876 	up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
877 	up->latency = up->calc_latency;
878 	schedule_work(&up->qos_work);
879 
880 	up->dll = quot & 0xff;
881 	up->dlh = quot >> 8;
882 	up->mdr1 = UART_OMAP_MDR1_DISABLE;
883 
884 	up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
885 			UART_FCR_ENABLE_FIFO;
886 
887 	/*
888 	 * Ok, we're now changing the port state. Do it with
889 	 * interrupts disabled.
890 	 */
891 	pm_runtime_get_sync(up->dev);
892 	spin_lock_irqsave(&up->port.lock, flags);
893 
894 	/*
895 	 * Update the per-port timeout.
896 	 */
897 	uart_update_timeout(port, termios->c_cflag, baud);
898 
899 	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
900 	if (termios->c_iflag & INPCK)
901 		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
902 	if (termios->c_iflag & (BRKINT | PARMRK))
903 		up->port.read_status_mask |= UART_LSR_BI;
904 
905 	/*
906 	 * Characters to ignore
907 	 */
908 	up->port.ignore_status_mask = 0;
909 	if (termios->c_iflag & IGNPAR)
910 		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
911 	if (termios->c_iflag & IGNBRK) {
912 		up->port.ignore_status_mask |= UART_LSR_BI;
913 		/*
914 		 * If we're ignoring parity and break indicators,
915 		 * ignore overruns too (for real raw support).
916 		 */
917 		if (termios->c_iflag & IGNPAR)
918 			up->port.ignore_status_mask |= UART_LSR_OE;
919 	}
920 
921 	/*
922 	 * ignore all characters if CREAD is not set
923 	 */
924 	if ((termios->c_cflag & CREAD) == 0)
925 		up->port.ignore_status_mask |= UART_LSR_DR;
926 
927 	/*
928 	 * Modem status interrupts
929 	 */
930 	up->ier &= ~UART_IER_MSI;
931 	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
932 		up->ier |= UART_IER_MSI;
933 	serial_out(up, UART_IER, up->ier);
934 	serial_out(up, UART_LCR, cval);		/* reset DLAB */
935 	up->lcr = cval;
936 	up->scr = 0;
937 
938 	/* FIFOs and DMA Settings */
939 
940 	/* FCR can be changed only when the
941 	 * baud clock is not running
942 	 * DLL_REG and DLH_REG set to 0.
943 	 */
944 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
945 	serial_out(up, UART_DLL, 0);
946 	serial_out(up, UART_DLM, 0);
947 	serial_out(up, UART_LCR, 0);
948 
949 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
950 
951 	up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
952 	up->efr &= ~UART_EFR_SCD;
953 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
954 
955 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
956 	up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
957 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
958 	/* FIFO ENABLE, DMA MODE */
959 
960 	up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
961 	/*
962 	 * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
963 	 * sets Enables the granularity of 1 for TRIGGER RX
964 	 * level. Along with setting RX FIFO trigger level
965 	 * to 1 (as noted below, 16 characters) and TLR[3:0]
966 	 * to zero this will result RX FIFO threshold level
967 	 * to 1 character, instead of 16 as noted in comment
968 	 * below.
969 	 */
970 
971 	/* Set receive FIFO threshold to 16 characters and
972 	 * transmit FIFO threshold to 32 spaces
973 	 */
974 	up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
975 	up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
976 	up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
977 		UART_FCR_ENABLE_FIFO;
978 
979 	serial_out(up, UART_FCR, up->fcr);
980 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
981 
982 	serial_out(up, UART_OMAP_SCR, up->scr);
983 
984 	/* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
985 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
986 	serial_out(up, UART_MCR, up->mcr);
987 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
988 	serial_out(up, UART_EFR, up->efr);
989 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
990 
991 	/* Protocol, Baud Rate, and Interrupt Settings */
992 
993 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
994 		serial_omap_mdr1_errataset(up, up->mdr1);
995 	else
996 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
997 
998 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
999 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1000 
1001 	serial_out(up, UART_LCR, 0);
1002 	serial_out(up, UART_IER, 0);
1003 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1004 
1005 	serial_out(up, UART_DLL, up->dll);	/* LS of divisor */
1006 	serial_out(up, UART_DLM, up->dlh);	/* MS of divisor */
1007 
1008 	serial_out(up, UART_LCR, 0);
1009 	serial_out(up, UART_IER, up->ier);
1010 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1011 
1012 	serial_out(up, UART_EFR, up->efr);
1013 	serial_out(up, UART_LCR, cval);
1014 
1015 	if (!serial_omap_baud_is_mode16(port, baud))
1016 		up->mdr1 = UART_OMAP_MDR1_13X_MODE;
1017 	else
1018 		up->mdr1 = UART_OMAP_MDR1_16X_MODE;
1019 
1020 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1021 		serial_omap_mdr1_errataset(up, up->mdr1);
1022 	else
1023 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1024 
1025 	/* Configure flow control */
1026 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1027 
1028 	/* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
1029 	serial_out(up, UART_XON1, termios->c_cc[VSTART]);
1030 	serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
1031 
1032 	/* Enable access to TCR/TLR */
1033 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1034 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1035 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
1036 
1037 	serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
1038 
1039 	up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
1040 
1041 	if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
1042 		/* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */
1043 		up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
1044 		up->efr |= UART_EFR_CTS;
1045 	} else {
1046 		/* Disable AUTORTS and AUTOCTS */
1047 		up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
1048 	}
1049 
1050 	if (up->port.flags & UPF_SOFT_FLOW) {
1051 		/* clear SW control mode bits */
1052 		up->efr &= OMAP_UART_SW_CLR;
1053 
1054 		/*
1055 		 * IXON Flag:
1056 		 * Enable XON/XOFF flow control on input.
1057 		 * Receiver compares XON1, XOFF1.
1058 		 */
1059 		if (termios->c_iflag & IXON)
1060 			up->efr |= OMAP_UART_SW_RX;
1061 
1062 		/*
1063 		 * IXOFF Flag:
1064 		 * Enable XON/XOFF flow control on output.
1065 		 * Transmit XON1, XOFF1
1066 		 */
1067 		if (termios->c_iflag & IXOFF) {
1068 			up->port.status |= UPSTAT_AUTOXOFF;
1069 			up->efr |= OMAP_UART_SW_TX;
1070 		}
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 	pm_runtime_mark_last_busy(up->dev);
1117 	pm_runtime_put_autosuspend(up->dev);
1118 }
1119 
1120 static void serial_omap_release_port(struct uart_port *port)
1121 {
1122 	dev_dbg(port->dev, "serial_omap_release_port+\n");
1123 }
1124 
1125 static int serial_omap_request_port(struct uart_port *port)
1126 {
1127 	dev_dbg(port->dev, "serial_omap_request_port+\n");
1128 	return 0;
1129 }
1130 
1131 static void serial_omap_config_port(struct uart_port *port, int flags)
1132 {
1133 	struct uart_omap_port *up = to_uart_omap_port(port);
1134 
1135 	dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
1136 							up->port.line);
1137 	up->port.type = PORT_OMAP;
1138 	up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
1139 }
1140 
1141 static int
1142 serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
1143 {
1144 	/* we don't want the core code to modify any port params */
1145 	dev_dbg(port->dev, "serial_omap_verify_port+\n");
1146 	return -EINVAL;
1147 }
1148 
1149 static const char *
1150 serial_omap_type(struct uart_port *port)
1151 {
1152 	struct uart_omap_port *up = to_uart_omap_port(port);
1153 
1154 	dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
1155 	return up->name;
1156 }
1157 
1158 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1159 
1160 static void __maybe_unused wait_for_xmitr(struct uart_omap_port *up)
1161 {
1162 	unsigned int status, tmout = 10000;
1163 
1164 	/* Wait up to 10ms for the character(s) to be sent. */
1165 	do {
1166 		status = serial_in(up, UART_LSR);
1167 
1168 		if (status & UART_LSR_BI)
1169 			up->lsr_break_flag = UART_LSR_BI;
1170 
1171 		if (--tmout == 0)
1172 			break;
1173 		udelay(1);
1174 	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
1175 
1176 	/* Wait up to 1s for flow control if necessary */
1177 	if (up->port.flags & UPF_CONS_FLOW) {
1178 		tmout = 1000000;
1179 		for (tmout = 1000000; tmout; tmout--) {
1180 			unsigned int msr = serial_in(up, UART_MSR);
1181 
1182 			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1183 			if (msr & UART_MSR_CTS)
1184 				break;
1185 
1186 			udelay(1);
1187 		}
1188 	}
1189 }
1190 
1191 #ifdef CONFIG_CONSOLE_POLL
1192 
1193 static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
1194 {
1195 	struct uart_omap_port *up = to_uart_omap_port(port);
1196 
1197 	pm_runtime_get_sync(up->dev);
1198 	wait_for_xmitr(up);
1199 	serial_out(up, UART_TX, ch);
1200 	pm_runtime_mark_last_busy(up->dev);
1201 	pm_runtime_put_autosuspend(up->dev);
1202 }
1203 
1204 static int serial_omap_poll_get_char(struct uart_port *port)
1205 {
1206 	struct uart_omap_port *up = to_uart_omap_port(port);
1207 	unsigned int status;
1208 
1209 	pm_runtime_get_sync(up->dev);
1210 	status = serial_in(up, UART_LSR);
1211 	if (!(status & UART_LSR_DR)) {
1212 		status = NO_POLL_CHAR;
1213 		goto out;
1214 	}
1215 
1216 	status = serial_in(up, UART_RX);
1217 
1218 out:
1219 	pm_runtime_mark_last_busy(up->dev);
1220 	pm_runtime_put_autosuspend(up->dev);
1221 
1222 	return status;
1223 }
1224 
1225 #endif /* CONFIG_CONSOLE_POLL */
1226 
1227 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
1228 
1229 #ifdef CONFIG_SERIAL_EARLYCON
1230 static unsigned int omap_serial_early_in(struct uart_port *port, int offset)
1231 {
1232 	offset <<= port->regshift;
1233 	return readw(port->membase + offset);
1234 }
1235 
1236 static void omap_serial_early_out(struct uart_port *port, int offset,
1237 				  int value)
1238 {
1239 	offset <<= port->regshift;
1240 	writew(value, port->membase + offset);
1241 }
1242 
1243 static void omap_serial_early_putc(struct uart_port *port, int c)
1244 {
1245 	unsigned int status;
1246 
1247 	for (;;) {
1248 		status = omap_serial_early_in(port, UART_LSR);
1249 		if ((status & BOTH_EMPTY) == BOTH_EMPTY)
1250 			break;
1251 		cpu_relax();
1252 	}
1253 	omap_serial_early_out(port, UART_TX, c);
1254 }
1255 
1256 static void early_omap_serial_write(struct console *console, const char *s,
1257 				    unsigned int count)
1258 {
1259 	struct earlycon_device *device = console->data;
1260 	struct uart_port *port = &device->port;
1261 
1262 	uart_console_write(port, s, count, omap_serial_early_putc);
1263 }
1264 
1265 static int __init early_omap_serial_setup(struct earlycon_device *device,
1266 					  const char *options)
1267 {
1268 	struct uart_port *port = &device->port;
1269 
1270 	if (!(device->port.membase || device->port.iobase))
1271 		return -ENODEV;
1272 
1273 	port->regshift = 2;
1274 	device->con->write = early_omap_serial_write;
1275 	return 0;
1276 }
1277 
1278 OF_EARLYCON_DECLARE(omapserial, "ti,omap2-uart", early_omap_serial_setup);
1279 OF_EARLYCON_DECLARE(omapserial, "ti,omap3-uart", early_omap_serial_setup);
1280 OF_EARLYCON_DECLARE(omapserial, "ti,omap4-uart", early_omap_serial_setup);
1281 #endif /* CONFIG_SERIAL_EARLYCON */
1282 
1283 static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
1284 
1285 static struct uart_driver serial_omap_reg;
1286 
1287 static void serial_omap_console_putchar(struct uart_port *port, int ch)
1288 {
1289 	struct uart_omap_port *up = to_uart_omap_port(port);
1290 
1291 	wait_for_xmitr(up);
1292 	serial_out(up, UART_TX, ch);
1293 }
1294 
1295 static void
1296 serial_omap_console_write(struct console *co, const char *s,
1297 		unsigned int count)
1298 {
1299 	struct uart_omap_port *up = serial_omap_console_ports[co->index];
1300 	unsigned long flags;
1301 	unsigned int ier;
1302 	int locked = 1;
1303 
1304 	pm_runtime_get_sync(up->dev);
1305 
1306 	local_irq_save(flags);
1307 	if (up->port.sysrq)
1308 		locked = 0;
1309 	else if (oops_in_progress)
1310 		locked = spin_trylock(&up->port.lock);
1311 	else
1312 		spin_lock(&up->port.lock);
1313 
1314 	/*
1315 	 * First save the IER then disable the interrupts
1316 	 */
1317 	ier = serial_in(up, UART_IER);
1318 	serial_out(up, UART_IER, 0);
1319 
1320 	uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1321 
1322 	/*
1323 	 * Finally, wait for transmitter to become empty
1324 	 * and restore the IER
1325 	 */
1326 	wait_for_xmitr(up);
1327 	serial_out(up, UART_IER, ier);
1328 	/*
1329 	 * The receive handling will happen properly because the
1330 	 * receive ready bit will still be set; it is not cleared
1331 	 * on read.  However, modem control will not, we must
1332 	 * call it if we have saved something in the saved flags
1333 	 * while processing with interrupts off.
1334 	 */
1335 	if (up->msr_saved_flags)
1336 		check_modem_status(up);
1337 
1338 	pm_runtime_mark_last_busy(up->dev);
1339 	pm_runtime_put_autosuspend(up->dev);
1340 	if (locked)
1341 		spin_unlock(&up->port.lock);
1342 	local_irq_restore(flags);
1343 }
1344 
1345 static int __init
1346 serial_omap_console_setup(struct console *co, char *options)
1347 {
1348 	struct uart_omap_port *up;
1349 	int baud = 115200;
1350 	int bits = 8;
1351 	int parity = 'n';
1352 	int flow = 'n';
1353 
1354 	if (serial_omap_console_ports[co->index] == NULL)
1355 		return -ENODEV;
1356 	up = serial_omap_console_ports[co->index];
1357 
1358 	if (options)
1359 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1360 
1361 	return uart_set_options(&up->port, co, baud, parity, bits, flow);
1362 }
1363 
1364 static struct console serial_omap_console = {
1365 	.name		= OMAP_SERIAL_NAME,
1366 	.write		= serial_omap_console_write,
1367 	.device		= uart_console_device,
1368 	.setup		= serial_omap_console_setup,
1369 	.flags		= CON_PRINTBUFFER,
1370 	.index		= -1,
1371 	.data		= &serial_omap_reg,
1372 };
1373 
1374 static void serial_omap_add_console_port(struct uart_omap_port *up)
1375 {
1376 	serial_omap_console_ports[up->port.line] = up;
1377 }
1378 
1379 #define OMAP_CONSOLE	(&serial_omap_console)
1380 
1381 #else
1382 
1383 #define OMAP_CONSOLE	NULL
1384 
1385 static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1386 {}
1387 
1388 #endif
1389 
1390 /* Enable or disable the rs485 support */
1391 static int
1392 serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485)
1393 {
1394 	struct uart_omap_port *up = to_uart_omap_port(port);
1395 	unsigned int mode;
1396 	int val;
1397 
1398 	pm_runtime_get_sync(up->dev);
1399 
1400 	/* Disable interrupts from this port */
1401 	mode = up->ier;
1402 	up->ier = 0;
1403 	serial_out(up, UART_IER, 0);
1404 
1405 	/* Clamp the delays to [0, 100ms] */
1406 	rs485->delay_rts_before_send = min(rs485->delay_rts_before_send, 100U);
1407 	rs485->delay_rts_after_send  = min(rs485->delay_rts_after_send, 100U);
1408 
1409 	/* store new config */
1410 	port->rs485 = *rs485;
1411 
1412 	/*
1413 	 * Just as a precaution, only allow rs485
1414 	 * to be enabled if the gpio pin is valid
1415 	 */
1416 	if (up->rts_gpiod) {
1417 		/* enable / disable rts */
1418 		val = (port->rs485.flags & SER_RS485_ENABLED) ?
1419 			SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
1420 		val = (port->rs485.flags & val) ? 1 : 0;
1421 		gpiod_set_value(up->rts_gpiod, val);
1422 	} else
1423 		port->rs485.flags &= ~SER_RS485_ENABLED;
1424 
1425 	/* Enable interrupts */
1426 	up->ier = mode;
1427 	serial_out(up, UART_IER, up->ier);
1428 
1429 	/* If RS-485 is disabled, make sure the THR interrupt is fired when
1430 	 * TX FIFO is below the trigger level.
1431 	 */
1432 	if (!(port->rs485.flags & SER_RS485_ENABLED) &&
1433 	    (up->scr & OMAP_UART_SCR_TX_EMPTY)) {
1434 		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
1435 		serial_out(up, UART_OMAP_SCR, up->scr);
1436 	}
1437 
1438 	pm_runtime_mark_last_busy(up->dev);
1439 	pm_runtime_put_autosuspend(up->dev);
1440 
1441 	return 0;
1442 }
1443 
1444 static const struct uart_ops serial_omap_pops = {
1445 	.tx_empty	= serial_omap_tx_empty,
1446 	.set_mctrl	= serial_omap_set_mctrl,
1447 	.get_mctrl	= serial_omap_get_mctrl,
1448 	.stop_tx	= serial_omap_stop_tx,
1449 	.start_tx	= serial_omap_start_tx,
1450 	.throttle	= serial_omap_throttle,
1451 	.unthrottle	= serial_omap_unthrottle,
1452 	.stop_rx	= serial_omap_stop_rx,
1453 	.enable_ms	= serial_omap_enable_ms,
1454 	.break_ctl	= serial_omap_break_ctl,
1455 	.startup	= serial_omap_startup,
1456 	.shutdown	= serial_omap_shutdown,
1457 	.set_termios	= serial_omap_set_termios,
1458 	.pm		= serial_omap_pm,
1459 	.type		= serial_omap_type,
1460 	.release_port	= serial_omap_release_port,
1461 	.request_port	= serial_omap_request_port,
1462 	.config_port	= serial_omap_config_port,
1463 	.verify_port	= serial_omap_verify_port,
1464 #ifdef CONFIG_CONSOLE_POLL
1465 	.poll_put_char  = serial_omap_poll_put_char,
1466 	.poll_get_char  = serial_omap_poll_get_char,
1467 #endif
1468 };
1469 
1470 static struct uart_driver serial_omap_reg = {
1471 	.owner		= THIS_MODULE,
1472 	.driver_name	= "OMAP-SERIAL",
1473 	.dev_name	= OMAP_SERIAL_NAME,
1474 	.nr		= OMAP_MAX_HSUART_PORTS,
1475 	.cons		= OMAP_CONSOLE,
1476 };
1477 
1478 #ifdef CONFIG_PM_SLEEP
1479 static int serial_omap_prepare(struct device *dev)
1480 {
1481 	struct uart_omap_port *up = dev_get_drvdata(dev);
1482 
1483 	up->is_suspending = true;
1484 
1485 	return 0;
1486 }
1487 
1488 static void serial_omap_complete(struct device *dev)
1489 {
1490 	struct uart_omap_port *up = dev_get_drvdata(dev);
1491 
1492 	up->is_suspending = false;
1493 }
1494 
1495 static int serial_omap_suspend(struct device *dev)
1496 {
1497 	struct uart_omap_port *up = dev_get_drvdata(dev);
1498 
1499 	uart_suspend_port(&serial_omap_reg, &up->port);
1500 	flush_work(&up->qos_work);
1501 
1502 	if (device_may_wakeup(dev))
1503 		serial_omap_enable_wakeup(up, true);
1504 	else
1505 		serial_omap_enable_wakeup(up, false);
1506 
1507 	return 0;
1508 }
1509 
1510 static int serial_omap_resume(struct device *dev)
1511 {
1512 	struct uart_omap_port *up = dev_get_drvdata(dev);
1513 
1514 	if (device_may_wakeup(dev))
1515 		serial_omap_enable_wakeup(up, false);
1516 
1517 	uart_resume_port(&serial_omap_reg, &up->port);
1518 
1519 	return 0;
1520 }
1521 #else
1522 #define serial_omap_prepare NULL
1523 #define serial_omap_complete NULL
1524 #endif /* CONFIG_PM_SLEEP */
1525 
1526 static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
1527 {
1528 	u32 mvr, scheme;
1529 	u16 revision, major, minor;
1530 
1531 	mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
1532 
1533 	/* Check revision register scheme */
1534 	scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
1535 
1536 	switch (scheme) {
1537 	case 0: /* Legacy Scheme: OMAP2/3 */
1538 		/* MINOR_REV[0:4], MAJOR_REV[4:7] */
1539 		major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
1540 					OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
1541 		minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
1542 		break;
1543 	case 1:
1544 		/* New Scheme: OMAP4+ */
1545 		/* MINOR_REV[0:5], MAJOR_REV[8:10] */
1546 		major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
1547 					OMAP_UART_MVR_MAJ_SHIFT;
1548 		minor = (mvr & OMAP_UART_MVR_MIN_MASK);
1549 		break;
1550 	default:
1551 		dev_warn(up->dev,
1552 			"Unknown %s revision, defaulting to highest\n",
1553 			up->name);
1554 		/* highest possible revision */
1555 		major = 0xff;
1556 		minor = 0xff;
1557 	}
1558 
1559 	/* normalize revision for the driver */
1560 	revision = UART_BUILD_REVISION(major, minor);
1561 
1562 	switch (revision) {
1563 	case OMAP_UART_REV_46:
1564 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1565 				UART_ERRATA_i291_DMA_FORCEIDLE);
1566 		break;
1567 	case OMAP_UART_REV_52:
1568 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1569 				UART_ERRATA_i291_DMA_FORCEIDLE);
1570 		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1571 		break;
1572 	case OMAP_UART_REV_63:
1573 		up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
1574 		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1575 		break;
1576 	default:
1577 		break;
1578 	}
1579 }
1580 
1581 static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1582 {
1583 	struct omap_uart_port_info *omap_up_info;
1584 
1585 	omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1586 	if (!omap_up_info)
1587 		return NULL; /* out of memory */
1588 
1589 	of_property_read_u32(dev->of_node, "clock-frequency",
1590 					 &omap_up_info->uartclk);
1591 
1592 	omap_up_info->flags = UPF_BOOT_AUTOCONF;
1593 
1594 	return omap_up_info;
1595 }
1596 
1597 static int serial_omap_probe_rs485(struct uart_omap_port *up,
1598 				   struct device *dev)
1599 {
1600 	struct serial_rs485 *rs485conf = &up->port.rs485;
1601 	struct device_node *np = dev->of_node;
1602 	enum gpiod_flags gflags;
1603 	int ret;
1604 
1605 	rs485conf->flags = 0;
1606 	up->rts_gpiod = NULL;
1607 
1608 	if (!np)
1609 		return 0;
1610 
1611 	ret = uart_get_rs485_mode(&up->port);
1612 	if (ret)
1613 		return ret;
1614 
1615 	if (of_property_read_bool(np, "rs485-rts-active-high")) {
1616 		rs485conf->flags |= SER_RS485_RTS_ON_SEND;
1617 		rs485conf->flags &= ~SER_RS485_RTS_AFTER_SEND;
1618 	} else {
1619 		rs485conf->flags &= ~SER_RS485_RTS_ON_SEND;
1620 		rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
1621 	}
1622 
1623 	/* check for tx enable gpio */
1624 	gflags = rs485conf->flags & SER_RS485_RTS_AFTER_SEND ?
1625 		GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
1626 	up->rts_gpiod = devm_gpiod_get_optional(dev, "rts", gflags);
1627 	if (IS_ERR(up->rts_gpiod)) {
1628 		ret = PTR_ERR(up->rts_gpiod);
1629 	        if (ret == -EPROBE_DEFER)
1630 			return ret;
1631 		/*
1632 		 * FIXME: the code historically ignored any other error than
1633 		 * -EPROBE_DEFER and just went on without GPIO.
1634 		 */
1635 		up->rts_gpiod = NULL;
1636 	} else {
1637 		gpiod_set_consumer_name(up->rts_gpiod, "omap-serial");
1638 	}
1639 
1640 	return 0;
1641 }
1642 
1643 static int serial_omap_probe(struct platform_device *pdev)
1644 {
1645 	struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
1646 	struct uart_omap_port *up;
1647 	struct resource *mem;
1648 	void __iomem *base;
1649 	int uartirq = 0;
1650 	int wakeirq = 0;
1651 	int ret;
1652 
1653 	/* The optional wakeirq may be specified in the board dts file */
1654 	if (pdev->dev.of_node) {
1655 		uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0);
1656 		if (!uartirq)
1657 			return -EPROBE_DEFER;
1658 		wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
1659 		omap_up_info = of_get_uart_port_info(&pdev->dev);
1660 		pdev->dev.platform_data = omap_up_info;
1661 	} else {
1662 		uartirq = platform_get_irq(pdev, 0);
1663 		if (uartirq < 0)
1664 			return -EPROBE_DEFER;
1665 	}
1666 
1667 	up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
1668 	if (!up)
1669 		return -ENOMEM;
1670 
1671 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1672 	base = devm_ioremap_resource(&pdev->dev, mem);
1673 	if (IS_ERR(base))
1674 		return PTR_ERR(base);
1675 
1676 	up->dev = &pdev->dev;
1677 	up->port.dev = &pdev->dev;
1678 	up->port.type = PORT_OMAP;
1679 	up->port.iotype = UPIO_MEM;
1680 	up->port.irq = uartirq;
1681 	up->port.regshift = 2;
1682 	up->port.fifosize = 64;
1683 	up->port.ops = &serial_omap_pops;
1684 	up->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_OMAP_CONSOLE);
1685 
1686 	if (pdev->dev.of_node)
1687 		ret = of_alias_get_id(pdev->dev.of_node, "serial");
1688 	else
1689 		ret = pdev->id;
1690 
1691 	if (ret < 0) {
1692 		dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1693 			ret);
1694 		goto err_port_line;
1695 	}
1696 	up->port.line = ret;
1697 
1698 	if (up->port.line >= OMAP_MAX_HSUART_PORTS) {
1699 		dev_err(&pdev->dev, "uart ID %d >  MAX %d.\n", up->port.line,
1700 			OMAP_MAX_HSUART_PORTS);
1701 		ret = -ENXIO;
1702 		goto err_port_line;
1703 	}
1704 
1705 	up->wakeirq = wakeirq;
1706 	if (!up->wakeirq)
1707 		dev_info(up->port.dev, "no wakeirq for uart%d\n",
1708 			 up->port.line);
1709 
1710 	ret = serial_omap_probe_rs485(up, &pdev->dev);
1711 	if (ret < 0)
1712 		goto err_rs485;
1713 
1714 	sprintf(up->name, "OMAP UART%d", up->port.line);
1715 	up->port.mapbase = mem->start;
1716 	up->port.membase = base;
1717 	up->port.flags = omap_up_info->flags;
1718 	up->port.uartclk = omap_up_info->uartclk;
1719 	up->port.rs485_config = serial_omap_config_rs485;
1720 	if (!up->port.uartclk) {
1721 		up->port.uartclk = DEFAULT_CLK_SPEED;
1722 		dev_warn(&pdev->dev,
1723 			 "No clock speed specified: using default: %d\n",
1724 			 DEFAULT_CLK_SPEED);
1725 	}
1726 
1727 	up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1728 	up->calc_latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1729 	cpu_latency_qos_add_request(&up->pm_qos_request, up->latency);
1730 	INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1731 
1732 	platform_set_drvdata(pdev, up);
1733 	if (omap_up_info->autosuspend_timeout == 0)
1734 		omap_up_info->autosuspend_timeout = -1;
1735 
1736 	device_init_wakeup(up->dev, true);
1737 	pm_runtime_use_autosuspend(&pdev->dev);
1738 	pm_runtime_set_autosuspend_delay(&pdev->dev,
1739 			omap_up_info->autosuspend_timeout);
1740 
1741 	pm_runtime_irq_safe(&pdev->dev);
1742 	pm_runtime_enable(&pdev->dev);
1743 
1744 	pm_runtime_get_sync(&pdev->dev);
1745 
1746 	omap_serial_fill_features_erratas(up);
1747 
1748 	ui[up->port.line] = up;
1749 	serial_omap_add_console_port(up);
1750 
1751 	ret = uart_add_one_port(&serial_omap_reg, &up->port);
1752 	if (ret != 0)
1753 		goto err_add_port;
1754 
1755 	pm_runtime_mark_last_busy(up->dev);
1756 	pm_runtime_put_autosuspend(up->dev);
1757 	return 0;
1758 
1759 err_add_port:
1760 	pm_runtime_dont_use_autosuspend(&pdev->dev);
1761 	pm_runtime_put_sync(&pdev->dev);
1762 	pm_runtime_disable(&pdev->dev);
1763 	cpu_latency_qos_remove_request(&up->pm_qos_request);
1764 	device_init_wakeup(up->dev, false);
1765 err_rs485:
1766 err_port_line:
1767 	return ret;
1768 }
1769 
1770 static int serial_omap_remove(struct platform_device *dev)
1771 {
1772 	struct uart_omap_port *up = platform_get_drvdata(dev);
1773 
1774 	pm_runtime_get_sync(up->dev);
1775 
1776 	uart_remove_one_port(&serial_omap_reg, &up->port);
1777 
1778 	pm_runtime_dont_use_autosuspend(up->dev);
1779 	pm_runtime_put_sync(up->dev);
1780 	pm_runtime_disable(up->dev);
1781 	cpu_latency_qos_remove_request(&up->pm_qos_request);
1782 	device_init_wakeup(&dev->dev, false);
1783 
1784 	return 0;
1785 }
1786 
1787 /*
1788  * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1789  * The access to uart register after MDR1 Access
1790  * causes UART to corrupt data.
1791  *
1792  * Need a delay =
1793  * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1794  * give 10 times as much
1795  */
1796 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1797 {
1798 	u8 timeout = 255;
1799 
1800 	serial_out(up, UART_OMAP_MDR1, mdr1);
1801 	udelay(2);
1802 	serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1803 			UART_FCR_CLEAR_RCVR);
1804 	/*
1805 	 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1806 	 * TX_FIFO_E bit is 1.
1807 	 */
1808 	while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1809 				(UART_LSR_THRE | UART_LSR_DR))) {
1810 		timeout--;
1811 		if (!timeout) {
1812 			/* Should *never* happen. we warn and carry on */
1813 			dev_crit(up->dev, "Errata i202: timedout %x\n",
1814 						serial_in(up, UART_LSR));
1815 			break;
1816 		}
1817 		udelay(1);
1818 	}
1819 }
1820 
1821 #ifdef CONFIG_PM
1822 static void serial_omap_restore_context(struct uart_omap_port *up)
1823 {
1824 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1825 		serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1826 	else
1827 		serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1828 
1829 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1830 	serial_out(up, UART_EFR, UART_EFR_ECB);
1831 	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1832 	serial_out(up, UART_IER, 0x0);
1833 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1834 	serial_out(up, UART_DLL, up->dll);
1835 	serial_out(up, UART_DLM, up->dlh);
1836 	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1837 	serial_out(up, UART_IER, up->ier);
1838 	serial_out(up, UART_FCR, up->fcr);
1839 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1840 	serial_out(up, UART_MCR, up->mcr);
1841 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1842 	serial_out(up, UART_OMAP_SCR, up->scr);
1843 	serial_out(up, UART_EFR, up->efr);
1844 	serial_out(up, UART_LCR, up->lcr);
1845 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1846 		serial_omap_mdr1_errataset(up, up->mdr1);
1847 	else
1848 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1849 	serial_out(up, UART_OMAP_WER, up->wer);
1850 }
1851 
1852 static int serial_omap_runtime_suspend(struct device *dev)
1853 {
1854 	struct uart_omap_port *up = dev_get_drvdata(dev);
1855 
1856 	if (!up)
1857 		return -EINVAL;
1858 
1859 	/*
1860 	* When using 'no_console_suspend', the console UART must not be
1861 	* suspended. Since driver suspend is managed by runtime suspend,
1862 	* preventing runtime suspend (by returning error) will keep device
1863 	* active during suspend.
1864 	*/
1865 	if (up->is_suspending && !console_suspend_enabled &&
1866 	    uart_console(&up->port))
1867 		return -EBUSY;
1868 
1869 	up->context_loss_cnt = serial_omap_get_context_loss_count(up);
1870 
1871 	serial_omap_enable_wakeup(up, true);
1872 
1873 	up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1874 	schedule_work(&up->qos_work);
1875 
1876 	return 0;
1877 }
1878 
1879 static int serial_omap_runtime_resume(struct device *dev)
1880 {
1881 	struct uart_omap_port *up = dev_get_drvdata(dev);
1882 
1883 	int loss_cnt = serial_omap_get_context_loss_count(up);
1884 
1885 	serial_omap_enable_wakeup(up, false);
1886 
1887 	if (loss_cnt < 0) {
1888 		dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
1889 			loss_cnt);
1890 		serial_omap_restore_context(up);
1891 	} else if (up->context_loss_cnt != loss_cnt) {
1892 		serial_omap_restore_context(up);
1893 	}
1894 	up->latency = up->calc_latency;
1895 	schedule_work(&up->qos_work);
1896 
1897 	return 0;
1898 }
1899 #endif
1900 
1901 static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1902 	SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1903 	SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1904 				serial_omap_runtime_resume, NULL)
1905 	.prepare        = serial_omap_prepare,
1906 	.complete       = serial_omap_complete,
1907 };
1908 
1909 #if defined(CONFIG_OF)
1910 static const struct of_device_id omap_serial_of_match[] = {
1911 	{ .compatible = "ti,omap2-uart" },
1912 	{ .compatible = "ti,omap3-uart" },
1913 	{ .compatible = "ti,omap4-uart" },
1914 	{},
1915 };
1916 MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1917 #endif
1918 
1919 static struct platform_driver serial_omap_driver = {
1920 	.probe          = serial_omap_probe,
1921 	.remove         = serial_omap_remove,
1922 	.driver		= {
1923 		.name	= OMAP_SERIAL_DRIVER_NAME,
1924 		.pm	= &serial_omap_dev_pm_ops,
1925 		.of_match_table = of_match_ptr(omap_serial_of_match),
1926 	},
1927 };
1928 
1929 static int __init serial_omap_init(void)
1930 {
1931 	int ret;
1932 
1933 	ret = uart_register_driver(&serial_omap_reg);
1934 	if (ret != 0)
1935 		return ret;
1936 	ret = platform_driver_register(&serial_omap_driver);
1937 	if (ret != 0)
1938 		uart_unregister_driver(&serial_omap_reg);
1939 	return ret;
1940 }
1941 
1942 static void __exit serial_omap_exit(void)
1943 {
1944 	platform_driver_unregister(&serial_omap_driver);
1945 	uart_unregister_driver(&serial_omap_reg);
1946 }
1947 
1948 module_init(serial_omap_init);
1949 module_exit(serial_omap_exit);
1950 
1951 MODULE_DESCRIPTION("OMAP High Speed UART driver");
1952 MODULE_LICENSE("GPL");
1953 MODULE_AUTHOR("Texas Instruments Inc");
1954