xref: /openbmc/linux/drivers/tty/serial/omap-serial.c (revision e15a5365)
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 		case UART_IIR_RDI:
591 			serial_omap_rdi(up, lsr);
592 			break;
593 		case UART_IIR_RLSI:
594 			serial_omap_rlsi(up, lsr);
595 			break;
596 		case UART_IIR_CTS_RTS_DSR:
597 			/* simply try again */
598 			break;
599 		case UART_IIR_XOFF:
600 		default:
601 			break;
602 		}
603 	} while (max_count--);
604 
605 	spin_unlock(&up->port.lock);
606 
607 	tty_flip_buffer_push(&up->port.state->port);
608 
609 	pm_runtime_mark_last_busy(up->dev);
610 	pm_runtime_put_autosuspend(up->dev);
611 	up->port_activity = jiffies;
612 
613 	return ret;
614 }
615 
616 static unsigned int serial_omap_tx_empty(struct uart_port *port)
617 {
618 	struct uart_omap_port *up = to_uart_omap_port(port);
619 	unsigned long flags = 0;
620 	unsigned int ret = 0;
621 
622 	pm_runtime_get_sync(up->dev);
623 	dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
624 	spin_lock_irqsave(&up->port.lock, flags);
625 	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
626 	spin_unlock_irqrestore(&up->port.lock, flags);
627 	pm_runtime_mark_last_busy(up->dev);
628 	pm_runtime_put_autosuspend(up->dev);
629 	return ret;
630 }
631 
632 static unsigned int serial_omap_get_mctrl(struct uart_port *port)
633 {
634 	struct uart_omap_port *up = to_uart_omap_port(port);
635 	unsigned int status;
636 	unsigned int ret = 0;
637 
638 	pm_runtime_get_sync(up->dev);
639 	status = check_modem_status(up);
640 	pm_runtime_mark_last_busy(up->dev);
641 	pm_runtime_put_autosuspend(up->dev);
642 
643 	dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
644 
645 	if (status & UART_MSR_DCD)
646 		ret |= TIOCM_CAR;
647 	if (status & UART_MSR_RI)
648 		ret |= TIOCM_RNG;
649 	if (status & UART_MSR_DSR)
650 		ret |= TIOCM_DSR;
651 	if (status & UART_MSR_CTS)
652 		ret |= TIOCM_CTS;
653 	return ret;
654 }
655 
656 static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
657 {
658 	struct uart_omap_port *up = to_uart_omap_port(port);
659 	unsigned char mcr = 0, old_mcr, lcr;
660 
661 	dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
662 	if (mctrl & TIOCM_RTS)
663 		mcr |= UART_MCR_RTS;
664 	if (mctrl & TIOCM_DTR)
665 		mcr |= UART_MCR_DTR;
666 	if (mctrl & TIOCM_OUT1)
667 		mcr |= UART_MCR_OUT1;
668 	if (mctrl & TIOCM_OUT2)
669 		mcr |= UART_MCR_OUT2;
670 	if (mctrl & TIOCM_LOOP)
671 		mcr |= UART_MCR_LOOP;
672 
673 	pm_runtime_get_sync(up->dev);
674 	old_mcr = serial_in(up, UART_MCR);
675 	old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
676 		     UART_MCR_DTR | UART_MCR_RTS);
677 	up->mcr = old_mcr | mcr;
678 	serial_out(up, UART_MCR, up->mcr);
679 
680 	/* Turn off autoRTS if RTS is lowered; restore autoRTS if RTS raised */
681 	lcr = serial_in(up, UART_LCR);
682 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
683 	if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS))
684 		up->efr |= UART_EFR_RTS;
685 	else
686 		up->efr &= ~UART_EFR_RTS;
687 	serial_out(up, UART_EFR, up->efr);
688 	serial_out(up, UART_LCR, lcr);
689 
690 	pm_runtime_mark_last_busy(up->dev);
691 	pm_runtime_put_autosuspend(up->dev);
692 }
693 
694 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
695 {
696 	struct uart_omap_port *up = to_uart_omap_port(port);
697 	unsigned long flags = 0;
698 
699 	dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
700 	pm_runtime_get_sync(up->dev);
701 	spin_lock_irqsave(&up->port.lock, flags);
702 	if (break_state == -1)
703 		up->lcr |= UART_LCR_SBC;
704 	else
705 		up->lcr &= ~UART_LCR_SBC;
706 	serial_out(up, UART_LCR, up->lcr);
707 	spin_unlock_irqrestore(&up->port.lock, flags);
708 	pm_runtime_mark_last_busy(up->dev);
709 	pm_runtime_put_autosuspend(up->dev);
710 }
711 
712 static int serial_omap_startup(struct uart_port *port)
713 {
714 	struct uart_omap_port *up = to_uart_omap_port(port);
715 	unsigned long flags = 0;
716 	int retval;
717 
718 	/*
719 	 * Allocate the IRQ
720 	 */
721 	retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
722 				up->name, up);
723 	if (retval)
724 		return retval;
725 
726 	/* Optional wake-up IRQ */
727 	if (up->wakeirq) {
728 		retval = dev_pm_set_dedicated_wake_irq(up->dev, up->wakeirq);
729 		if (retval) {
730 			free_irq(up->port.irq, up);
731 			return retval;
732 		}
733 	}
734 
735 	dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
736 
737 	pm_runtime_get_sync(up->dev);
738 	/*
739 	 * Clear the FIFO buffers and disable them.
740 	 * (they will be reenabled in set_termios())
741 	 */
742 	serial_omap_clear_fifos(up);
743 
744 	/*
745 	 * Clear the interrupt registers.
746 	 */
747 	(void) serial_in(up, UART_LSR);
748 	if (serial_in(up, UART_LSR) & UART_LSR_DR)
749 		(void) serial_in(up, UART_RX);
750 	(void) serial_in(up, UART_IIR);
751 	(void) serial_in(up, UART_MSR);
752 
753 	/*
754 	 * Now, initialize the UART
755 	 */
756 	serial_out(up, UART_LCR, UART_LCR_WLEN8);
757 	spin_lock_irqsave(&up->port.lock, flags);
758 	/*
759 	 * Most PC uarts need OUT2 raised to enable interrupts.
760 	 */
761 	up->port.mctrl |= TIOCM_OUT2;
762 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
763 	spin_unlock_irqrestore(&up->port.lock, flags);
764 
765 	up->msr_saved_flags = 0;
766 	/*
767 	 * Finally, enable interrupts. Note: Modem status interrupts
768 	 * are set via set_termios(), which will be occurring imminently
769 	 * anyway, so we don't enable them here.
770 	 */
771 	up->ier = UART_IER_RLSI | UART_IER_RDI;
772 	serial_out(up, UART_IER, up->ier);
773 
774 	/* Enable module level wake up */
775 	up->wer = OMAP_UART_WER_MOD_WKUP;
776 	if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
777 		up->wer |= OMAP_UART_TX_WAKEUP_EN;
778 
779 	serial_out(up, UART_OMAP_WER, up->wer);
780 
781 	pm_runtime_mark_last_busy(up->dev);
782 	pm_runtime_put_autosuspend(up->dev);
783 	up->port_activity = jiffies;
784 	return 0;
785 }
786 
787 static void serial_omap_shutdown(struct uart_port *port)
788 {
789 	struct uart_omap_port *up = to_uart_omap_port(port);
790 	unsigned long flags = 0;
791 
792 	dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
793 
794 	pm_runtime_get_sync(up->dev);
795 	/*
796 	 * Disable interrupts from this port
797 	 */
798 	up->ier = 0;
799 	serial_out(up, UART_IER, 0);
800 
801 	spin_lock_irqsave(&up->port.lock, flags);
802 	up->port.mctrl &= ~TIOCM_OUT2;
803 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
804 	spin_unlock_irqrestore(&up->port.lock, flags);
805 
806 	/*
807 	 * Disable break condition and FIFOs
808 	 */
809 	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
810 	serial_omap_clear_fifos(up);
811 
812 	/*
813 	 * Read data port to reset things, and then free the irq
814 	 */
815 	if (serial_in(up, UART_LSR) & UART_LSR_DR)
816 		(void) serial_in(up, UART_RX);
817 
818 	pm_runtime_mark_last_busy(up->dev);
819 	pm_runtime_put_autosuspend(up->dev);
820 	free_irq(up->port.irq, up);
821 	dev_pm_clear_wake_irq(up->dev);
822 }
823 
824 static void serial_omap_uart_qos_work(struct work_struct *work)
825 {
826 	struct uart_omap_port *up = container_of(work, struct uart_omap_port,
827 						qos_work);
828 
829 	cpu_latency_qos_update_request(&up->pm_qos_request, up->latency);
830 }
831 
832 static void
833 serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
834 			struct ktermios *old)
835 {
836 	struct uart_omap_port *up = to_uart_omap_port(port);
837 	unsigned char cval = 0;
838 	unsigned long flags = 0;
839 	unsigned int baud, quot;
840 
841 	switch (termios->c_cflag & CSIZE) {
842 	case CS5:
843 		cval = UART_LCR_WLEN5;
844 		break;
845 	case CS6:
846 		cval = UART_LCR_WLEN6;
847 		break;
848 	case CS7:
849 		cval = UART_LCR_WLEN7;
850 		break;
851 	default:
852 	case CS8:
853 		cval = UART_LCR_WLEN8;
854 		break;
855 	}
856 
857 	if (termios->c_cflag & CSTOPB)
858 		cval |= UART_LCR_STOP;
859 	if (termios->c_cflag & PARENB)
860 		cval |= UART_LCR_PARITY;
861 	if (!(termios->c_cflag & PARODD))
862 		cval |= UART_LCR_EPAR;
863 	if (termios->c_cflag & CMSPAR)
864 		cval |= UART_LCR_SPAR;
865 
866 	/*
867 	 * Ask the core to calculate the divisor for us.
868 	 */
869 
870 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
871 	quot = serial_omap_get_divisor(port, baud);
872 
873 	/* calculate wakeup latency constraint */
874 	up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
875 	up->latency = up->calc_latency;
876 	schedule_work(&up->qos_work);
877 
878 	up->dll = quot & 0xff;
879 	up->dlh = quot >> 8;
880 	up->mdr1 = UART_OMAP_MDR1_DISABLE;
881 
882 	up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
883 			UART_FCR_ENABLE_FIFO;
884 
885 	/*
886 	 * Ok, we're now changing the port state. Do it with
887 	 * interrupts disabled.
888 	 */
889 	pm_runtime_get_sync(up->dev);
890 	spin_lock_irqsave(&up->port.lock, flags);
891 
892 	/*
893 	 * Update the per-port timeout.
894 	 */
895 	uart_update_timeout(port, termios->c_cflag, baud);
896 
897 	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
898 	if (termios->c_iflag & INPCK)
899 		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
900 	if (termios->c_iflag & (BRKINT | PARMRK))
901 		up->port.read_status_mask |= UART_LSR_BI;
902 
903 	/*
904 	 * Characters to ignore
905 	 */
906 	up->port.ignore_status_mask = 0;
907 	if (termios->c_iflag & IGNPAR)
908 		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
909 	if (termios->c_iflag & IGNBRK) {
910 		up->port.ignore_status_mask |= UART_LSR_BI;
911 		/*
912 		 * If we're ignoring parity and break indicators,
913 		 * ignore overruns too (for real raw support).
914 		 */
915 		if (termios->c_iflag & IGNPAR)
916 			up->port.ignore_status_mask |= UART_LSR_OE;
917 	}
918 
919 	/*
920 	 * ignore all characters if CREAD is not set
921 	 */
922 	if ((termios->c_cflag & CREAD) == 0)
923 		up->port.ignore_status_mask |= UART_LSR_DR;
924 
925 	/*
926 	 * Modem status interrupts
927 	 */
928 	up->ier &= ~UART_IER_MSI;
929 	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
930 		up->ier |= UART_IER_MSI;
931 	serial_out(up, UART_IER, up->ier);
932 	serial_out(up, UART_LCR, cval);		/* reset DLAB */
933 	up->lcr = cval;
934 	up->scr = 0;
935 
936 	/* FIFOs and DMA Settings */
937 
938 	/* FCR can be changed only when the
939 	 * baud clock is not running
940 	 * DLL_REG and DLH_REG set to 0.
941 	 */
942 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
943 	serial_out(up, UART_DLL, 0);
944 	serial_out(up, UART_DLM, 0);
945 	serial_out(up, UART_LCR, 0);
946 
947 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
948 
949 	up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
950 	up->efr &= ~UART_EFR_SCD;
951 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
952 
953 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
954 	up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
955 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
956 	/* FIFO ENABLE, DMA MODE */
957 
958 	up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
959 	/*
960 	 * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
961 	 * sets Enables the granularity of 1 for TRIGGER RX
962 	 * level. Along with setting RX FIFO trigger level
963 	 * to 1 (as noted below, 16 characters) and TLR[3:0]
964 	 * to zero this will result RX FIFO threshold level
965 	 * to 1 character, instead of 16 as noted in comment
966 	 * below.
967 	 */
968 
969 	/* Set receive FIFO threshold to 16 characters and
970 	 * transmit FIFO threshold to 32 spaces
971 	 */
972 	up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
973 	up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
974 	up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
975 		UART_FCR_ENABLE_FIFO;
976 
977 	serial_out(up, UART_FCR, up->fcr);
978 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
979 
980 	serial_out(up, UART_OMAP_SCR, up->scr);
981 
982 	/* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
983 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
984 	serial_out(up, UART_MCR, up->mcr);
985 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
986 	serial_out(up, UART_EFR, up->efr);
987 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
988 
989 	/* Protocol, Baud Rate, and Interrupt Settings */
990 
991 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
992 		serial_omap_mdr1_errataset(up, up->mdr1);
993 	else
994 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
995 
996 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
997 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
998 
999 	serial_out(up, UART_LCR, 0);
1000 	serial_out(up, UART_IER, 0);
1001 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1002 
1003 	serial_out(up, UART_DLL, up->dll);	/* LS of divisor */
1004 	serial_out(up, UART_DLM, up->dlh);	/* MS of divisor */
1005 
1006 	serial_out(up, UART_LCR, 0);
1007 	serial_out(up, UART_IER, up->ier);
1008 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1009 
1010 	serial_out(up, UART_EFR, up->efr);
1011 	serial_out(up, UART_LCR, cval);
1012 
1013 	if (!serial_omap_baud_is_mode16(port, baud))
1014 		up->mdr1 = UART_OMAP_MDR1_13X_MODE;
1015 	else
1016 		up->mdr1 = UART_OMAP_MDR1_16X_MODE;
1017 
1018 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1019 		serial_omap_mdr1_errataset(up, up->mdr1);
1020 	else
1021 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1022 
1023 	/* Configure flow control */
1024 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1025 
1026 	/* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
1027 	serial_out(up, UART_XON1, termios->c_cc[VSTART]);
1028 	serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
1029 
1030 	/* Enable access to TCR/TLR */
1031 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1032 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1033 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
1034 
1035 	serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
1036 
1037 	up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
1038 
1039 	if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
1040 		/* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */
1041 		up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
1042 		up->efr |= UART_EFR_CTS;
1043 	} else {
1044 		/* Disable AUTORTS and AUTOCTS */
1045 		up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
1046 	}
1047 
1048 	if (up->port.flags & UPF_SOFT_FLOW) {
1049 		/* clear SW control mode bits */
1050 		up->efr &= OMAP_UART_SW_CLR;
1051 
1052 		/*
1053 		 * IXON Flag:
1054 		 * Enable XON/XOFF flow control on input.
1055 		 * Receiver compares XON1, XOFF1.
1056 		 */
1057 		if (termios->c_iflag & IXON)
1058 			up->efr |= OMAP_UART_SW_RX;
1059 
1060 		/*
1061 		 * IXOFF Flag:
1062 		 * Enable XON/XOFF flow control on output.
1063 		 * Transmit XON1, XOFF1
1064 		 */
1065 		if (termios->c_iflag & IXOFF) {
1066 			up->port.status |= UPSTAT_AUTOXOFF;
1067 			up->efr |= OMAP_UART_SW_TX;
1068 		}
1069 
1070 		/*
1071 		 * IXANY Flag:
1072 		 * Enable any character to restart output.
1073 		 * Operation resumes after receiving any
1074 		 * character after recognition of the XOFF character
1075 		 */
1076 		if (termios->c_iflag & IXANY)
1077 			up->mcr |= UART_MCR_XONANY;
1078 		else
1079 			up->mcr &= ~UART_MCR_XONANY;
1080 	}
1081 	serial_out(up, UART_MCR, up->mcr);
1082 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1083 	serial_out(up, UART_EFR, up->efr);
1084 	serial_out(up, UART_LCR, up->lcr);
1085 
1086 	serial_omap_set_mctrl(&up->port, up->port.mctrl);
1087 
1088 	spin_unlock_irqrestore(&up->port.lock, flags);
1089 	pm_runtime_mark_last_busy(up->dev);
1090 	pm_runtime_put_autosuspend(up->dev);
1091 	dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
1092 }
1093 
1094 static void
1095 serial_omap_pm(struct uart_port *port, unsigned int state,
1096 	       unsigned int oldstate)
1097 {
1098 	struct uart_omap_port *up = to_uart_omap_port(port);
1099 	unsigned char efr;
1100 
1101 	dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
1102 
1103 	pm_runtime_get_sync(up->dev);
1104 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1105 	efr = serial_in(up, UART_EFR);
1106 	serial_out(up, UART_EFR, efr | UART_EFR_ECB);
1107 	serial_out(up, UART_LCR, 0);
1108 
1109 	serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
1110 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1111 	serial_out(up, UART_EFR, efr);
1112 	serial_out(up, UART_LCR, 0);
1113 
1114 	pm_runtime_mark_last_busy(up->dev);
1115 	pm_runtime_put_autosuspend(up->dev);
1116 }
1117 
1118 static void serial_omap_release_port(struct uart_port *port)
1119 {
1120 	dev_dbg(port->dev, "serial_omap_release_port+\n");
1121 }
1122 
1123 static int serial_omap_request_port(struct uart_port *port)
1124 {
1125 	dev_dbg(port->dev, "serial_omap_request_port+\n");
1126 	return 0;
1127 }
1128 
1129 static void serial_omap_config_port(struct uart_port *port, int flags)
1130 {
1131 	struct uart_omap_port *up = to_uart_omap_port(port);
1132 
1133 	dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
1134 							up->port.line);
1135 	up->port.type = PORT_OMAP;
1136 	up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
1137 }
1138 
1139 static int
1140 serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
1141 {
1142 	/* we don't want the core code to modify any port params */
1143 	dev_dbg(port->dev, "serial_omap_verify_port+\n");
1144 	return -EINVAL;
1145 }
1146 
1147 static const char *
1148 serial_omap_type(struct uart_port *port)
1149 {
1150 	struct uart_omap_port *up = to_uart_omap_port(port);
1151 
1152 	dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
1153 	return up->name;
1154 }
1155 
1156 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1157 
1158 static void __maybe_unused wait_for_xmitr(struct uart_omap_port *up)
1159 {
1160 	unsigned int status, tmout = 10000;
1161 
1162 	/* Wait up to 10ms for the character(s) to be sent. */
1163 	do {
1164 		status = serial_in(up, UART_LSR);
1165 
1166 		if (status & UART_LSR_BI)
1167 			up->lsr_break_flag = UART_LSR_BI;
1168 
1169 		if (--tmout == 0)
1170 			break;
1171 		udelay(1);
1172 	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
1173 
1174 	/* Wait up to 1s for flow control if necessary */
1175 	if (up->port.flags & UPF_CONS_FLOW) {
1176 		tmout = 1000000;
1177 		for (tmout = 1000000; tmout; tmout--) {
1178 			unsigned int msr = serial_in(up, UART_MSR);
1179 
1180 			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1181 			if (msr & UART_MSR_CTS)
1182 				break;
1183 
1184 			udelay(1);
1185 		}
1186 	}
1187 }
1188 
1189 #ifdef CONFIG_CONSOLE_POLL
1190 
1191 static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
1192 {
1193 	struct uart_omap_port *up = to_uart_omap_port(port);
1194 
1195 	pm_runtime_get_sync(up->dev);
1196 	wait_for_xmitr(up);
1197 	serial_out(up, UART_TX, ch);
1198 	pm_runtime_mark_last_busy(up->dev);
1199 	pm_runtime_put_autosuspend(up->dev);
1200 }
1201 
1202 static int serial_omap_poll_get_char(struct uart_port *port)
1203 {
1204 	struct uart_omap_port *up = to_uart_omap_port(port);
1205 	unsigned int status;
1206 
1207 	pm_runtime_get_sync(up->dev);
1208 	status = serial_in(up, UART_LSR);
1209 	if (!(status & UART_LSR_DR)) {
1210 		status = NO_POLL_CHAR;
1211 		goto out;
1212 	}
1213 
1214 	status = serial_in(up, UART_RX);
1215 
1216 out:
1217 	pm_runtime_mark_last_busy(up->dev);
1218 	pm_runtime_put_autosuspend(up->dev);
1219 
1220 	return status;
1221 }
1222 
1223 #endif /* CONFIG_CONSOLE_POLL */
1224 
1225 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
1226 
1227 #ifdef CONFIG_SERIAL_EARLYCON
1228 static unsigned int omap_serial_early_in(struct uart_port *port, int offset)
1229 {
1230 	offset <<= port->regshift;
1231 	return readw(port->membase + offset);
1232 }
1233 
1234 static void omap_serial_early_out(struct uart_port *port, int offset,
1235 				  int value)
1236 {
1237 	offset <<= port->regshift;
1238 	writew(value, port->membase + offset);
1239 }
1240 
1241 static void omap_serial_early_putc(struct uart_port *port, int c)
1242 {
1243 	unsigned int status;
1244 
1245 	for (;;) {
1246 		status = omap_serial_early_in(port, UART_LSR);
1247 		if ((status & BOTH_EMPTY) == BOTH_EMPTY)
1248 			break;
1249 		cpu_relax();
1250 	}
1251 	omap_serial_early_out(port, UART_TX, c);
1252 }
1253 
1254 static void early_omap_serial_write(struct console *console, const char *s,
1255 				    unsigned int count)
1256 {
1257 	struct earlycon_device *device = console->data;
1258 	struct uart_port *port = &device->port;
1259 
1260 	uart_console_write(port, s, count, omap_serial_early_putc);
1261 }
1262 
1263 static int __init early_omap_serial_setup(struct earlycon_device *device,
1264 					  const char *options)
1265 {
1266 	struct uart_port *port = &device->port;
1267 
1268 	if (!(device->port.membase || device->port.iobase))
1269 		return -ENODEV;
1270 
1271 	port->regshift = 2;
1272 	device->con->write = early_omap_serial_write;
1273 	return 0;
1274 }
1275 
1276 OF_EARLYCON_DECLARE(omapserial, "ti,omap2-uart", early_omap_serial_setup);
1277 OF_EARLYCON_DECLARE(omapserial, "ti,omap3-uart", early_omap_serial_setup);
1278 OF_EARLYCON_DECLARE(omapserial, "ti,omap4-uart", early_omap_serial_setup);
1279 #endif /* CONFIG_SERIAL_EARLYCON */
1280 
1281 static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
1282 
1283 static struct uart_driver serial_omap_reg;
1284 
1285 static void serial_omap_console_putchar(struct uart_port *port, int ch)
1286 {
1287 	struct uart_omap_port *up = to_uart_omap_port(port);
1288 
1289 	wait_for_xmitr(up);
1290 	serial_out(up, UART_TX, ch);
1291 }
1292 
1293 static void
1294 serial_omap_console_write(struct console *co, const char *s,
1295 		unsigned int count)
1296 {
1297 	struct uart_omap_port *up = serial_omap_console_ports[co->index];
1298 	unsigned long flags;
1299 	unsigned int ier;
1300 	int locked = 1;
1301 
1302 	pm_runtime_get_sync(up->dev);
1303 
1304 	local_irq_save(flags);
1305 	if (up->port.sysrq)
1306 		locked = 0;
1307 	else if (oops_in_progress)
1308 		locked = spin_trylock(&up->port.lock);
1309 	else
1310 		spin_lock(&up->port.lock);
1311 
1312 	/*
1313 	 * First save the IER then disable the interrupts
1314 	 */
1315 	ier = serial_in(up, UART_IER);
1316 	serial_out(up, UART_IER, 0);
1317 
1318 	uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1319 
1320 	/*
1321 	 * Finally, wait for transmitter to become empty
1322 	 * and restore the IER
1323 	 */
1324 	wait_for_xmitr(up);
1325 	serial_out(up, UART_IER, ier);
1326 	/*
1327 	 * The receive handling will happen properly because the
1328 	 * receive ready bit will still be set; it is not cleared
1329 	 * on read.  However, modem control will not, we must
1330 	 * call it if we have saved something in the saved flags
1331 	 * while processing with interrupts off.
1332 	 */
1333 	if (up->msr_saved_flags)
1334 		check_modem_status(up);
1335 
1336 	pm_runtime_mark_last_busy(up->dev);
1337 	pm_runtime_put_autosuspend(up->dev);
1338 	if (locked)
1339 		spin_unlock(&up->port.lock);
1340 	local_irq_restore(flags);
1341 }
1342 
1343 static int __init
1344 serial_omap_console_setup(struct console *co, char *options)
1345 {
1346 	struct uart_omap_port *up;
1347 	int baud = 115200;
1348 	int bits = 8;
1349 	int parity = 'n';
1350 	int flow = 'n';
1351 
1352 	if (serial_omap_console_ports[co->index] == NULL)
1353 		return -ENODEV;
1354 	up = serial_omap_console_ports[co->index];
1355 
1356 	if (options)
1357 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1358 
1359 	return uart_set_options(&up->port, co, baud, parity, bits, flow);
1360 }
1361 
1362 static struct console serial_omap_console = {
1363 	.name		= OMAP_SERIAL_NAME,
1364 	.write		= serial_omap_console_write,
1365 	.device		= uart_console_device,
1366 	.setup		= serial_omap_console_setup,
1367 	.flags		= CON_PRINTBUFFER,
1368 	.index		= -1,
1369 	.data		= &serial_omap_reg,
1370 };
1371 
1372 static void serial_omap_add_console_port(struct uart_omap_port *up)
1373 {
1374 	serial_omap_console_ports[up->port.line] = up;
1375 }
1376 
1377 #define OMAP_CONSOLE	(&serial_omap_console)
1378 
1379 #else
1380 
1381 #define OMAP_CONSOLE	NULL
1382 
1383 static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1384 {}
1385 
1386 #endif
1387 
1388 /* Enable or disable the rs485 support */
1389 static int
1390 serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485)
1391 {
1392 	struct uart_omap_port *up = to_uart_omap_port(port);
1393 	unsigned int mode;
1394 	int val;
1395 
1396 	pm_runtime_get_sync(up->dev);
1397 
1398 	/* Disable interrupts from this port */
1399 	mode = up->ier;
1400 	up->ier = 0;
1401 	serial_out(up, UART_IER, 0);
1402 
1403 	/* Clamp the delays to [0, 100ms] */
1404 	rs485->delay_rts_before_send = min(rs485->delay_rts_before_send, 100U);
1405 	rs485->delay_rts_after_send  = min(rs485->delay_rts_after_send, 100U);
1406 
1407 	/* store new config */
1408 	port->rs485 = *rs485;
1409 
1410 	/*
1411 	 * Just as a precaution, only allow rs485
1412 	 * to be enabled if the gpio pin is valid
1413 	 */
1414 	if (up->rts_gpiod) {
1415 		/* enable / disable rts */
1416 		val = (port->rs485.flags & SER_RS485_ENABLED) ?
1417 			SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
1418 		val = (port->rs485.flags & val) ? 1 : 0;
1419 		gpiod_set_value(up->rts_gpiod, val);
1420 	} else
1421 		port->rs485.flags &= ~SER_RS485_ENABLED;
1422 
1423 	/* Enable interrupts */
1424 	up->ier = mode;
1425 	serial_out(up, UART_IER, up->ier);
1426 
1427 	/* If RS-485 is disabled, make sure the THR interrupt is fired when
1428 	 * TX FIFO is below the trigger level.
1429 	 */
1430 	if (!(port->rs485.flags & SER_RS485_ENABLED) &&
1431 	    (up->scr & OMAP_UART_SCR_TX_EMPTY)) {
1432 		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
1433 		serial_out(up, UART_OMAP_SCR, up->scr);
1434 	}
1435 
1436 	pm_runtime_mark_last_busy(up->dev);
1437 	pm_runtime_put_autosuspend(up->dev);
1438 
1439 	return 0;
1440 }
1441 
1442 static const struct uart_ops serial_omap_pops = {
1443 	.tx_empty	= serial_omap_tx_empty,
1444 	.set_mctrl	= serial_omap_set_mctrl,
1445 	.get_mctrl	= serial_omap_get_mctrl,
1446 	.stop_tx	= serial_omap_stop_tx,
1447 	.start_tx	= serial_omap_start_tx,
1448 	.throttle	= serial_omap_throttle,
1449 	.unthrottle	= serial_omap_unthrottle,
1450 	.stop_rx	= serial_omap_stop_rx,
1451 	.enable_ms	= serial_omap_enable_ms,
1452 	.break_ctl	= serial_omap_break_ctl,
1453 	.startup	= serial_omap_startup,
1454 	.shutdown	= serial_omap_shutdown,
1455 	.set_termios	= serial_omap_set_termios,
1456 	.pm		= serial_omap_pm,
1457 	.type		= serial_omap_type,
1458 	.release_port	= serial_omap_release_port,
1459 	.request_port	= serial_omap_request_port,
1460 	.config_port	= serial_omap_config_port,
1461 	.verify_port	= serial_omap_verify_port,
1462 #ifdef CONFIG_CONSOLE_POLL
1463 	.poll_put_char  = serial_omap_poll_put_char,
1464 	.poll_get_char  = serial_omap_poll_get_char,
1465 #endif
1466 };
1467 
1468 static struct uart_driver serial_omap_reg = {
1469 	.owner		= THIS_MODULE,
1470 	.driver_name	= "OMAP-SERIAL",
1471 	.dev_name	= OMAP_SERIAL_NAME,
1472 	.nr		= OMAP_MAX_HSUART_PORTS,
1473 	.cons		= OMAP_CONSOLE,
1474 };
1475 
1476 #ifdef CONFIG_PM_SLEEP
1477 static int serial_omap_prepare(struct device *dev)
1478 {
1479 	struct uart_omap_port *up = dev_get_drvdata(dev);
1480 
1481 	up->is_suspending = true;
1482 
1483 	return 0;
1484 }
1485 
1486 static void serial_omap_complete(struct device *dev)
1487 {
1488 	struct uart_omap_port *up = dev_get_drvdata(dev);
1489 
1490 	up->is_suspending = false;
1491 }
1492 
1493 static int serial_omap_suspend(struct device *dev)
1494 {
1495 	struct uart_omap_port *up = dev_get_drvdata(dev);
1496 
1497 	uart_suspend_port(&serial_omap_reg, &up->port);
1498 	flush_work(&up->qos_work);
1499 
1500 	if (device_may_wakeup(dev))
1501 		serial_omap_enable_wakeup(up, true);
1502 	else
1503 		serial_omap_enable_wakeup(up, false);
1504 
1505 	return 0;
1506 }
1507 
1508 static int serial_omap_resume(struct device *dev)
1509 {
1510 	struct uart_omap_port *up = dev_get_drvdata(dev);
1511 
1512 	if (device_may_wakeup(dev))
1513 		serial_omap_enable_wakeup(up, false);
1514 
1515 	uart_resume_port(&serial_omap_reg, &up->port);
1516 
1517 	return 0;
1518 }
1519 #else
1520 #define serial_omap_prepare NULL
1521 #define serial_omap_complete NULL
1522 #endif /* CONFIG_PM_SLEEP */
1523 
1524 static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
1525 {
1526 	u32 mvr, scheme;
1527 	u16 revision, major, minor;
1528 
1529 	mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
1530 
1531 	/* Check revision register scheme */
1532 	scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
1533 
1534 	switch (scheme) {
1535 	case 0: /* Legacy Scheme: OMAP2/3 */
1536 		/* MINOR_REV[0:4], MAJOR_REV[4:7] */
1537 		major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
1538 					OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
1539 		minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
1540 		break;
1541 	case 1:
1542 		/* New Scheme: OMAP4+ */
1543 		/* MINOR_REV[0:5], MAJOR_REV[8:10] */
1544 		major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
1545 					OMAP_UART_MVR_MAJ_SHIFT;
1546 		minor = (mvr & OMAP_UART_MVR_MIN_MASK);
1547 		break;
1548 	default:
1549 		dev_warn(up->dev,
1550 			"Unknown %s revision, defaulting to highest\n",
1551 			up->name);
1552 		/* highest possible revision */
1553 		major = 0xff;
1554 		minor = 0xff;
1555 	}
1556 
1557 	/* normalize revision for the driver */
1558 	revision = UART_BUILD_REVISION(major, minor);
1559 
1560 	switch (revision) {
1561 	case OMAP_UART_REV_46:
1562 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1563 				UART_ERRATA_i291_DMA_FORCEIDLE);
1564 		break;
1565 	case OMAP_UART_REV_52:
1566 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1567 				UART_ERRATA_i291_DMA_FORCEIDLE);
1568 		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1569 		break;
1570 	case OMAP_UART_REV_63:
1571 		up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
1572 		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1573 		break;
1574 	default:
1575 		break;
1576 	}
1577 }
1578 
1579 static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1580 {
1581 	struct omap_uart_port_info *omap_up_info;
1582 
1583 	omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1584 	if (!omap_up_info)
1585 		return NULL; /* out of memory */
1586 
1587 	of_property_read_u32(dev->of_node, "clock-frequency",
1588 					 &omap_up_info->uartclk);
1589 
1590 	omap_up_info->flags = UPF_BOOT_AUTOCONF;
1591 
1592 	return omap_up_info;
1593 }
1594 
1595 static int serial_omap_probe_rs485(struct uart_omap_port *up,
1596 				   struct device *dev)
1597 {
1598 	struct serial_rs485 *rs485conf = &up->port.rs485;
1599 	struct device_node *np = dev->of_node;
1600 	enum gpiod_flags gflags;
1601 	int ret;
1602 
1603 	rs485conf->flags = 0;
1604 	up->rts_gpiod = NULL;
1605 
1606 	if (!np)
1607 		return 0;
1608 
1609 	ret = uart_get_rs485_mode(&up->port);
1610 	if (ret)
1611 		return ret;
1612 
1613 	if (of_property_read_bool(np, "rs485-rts-active-high")) {
1614 		rs485conf->flags |= SER_RS485_RTS_ON_SEND;
1615 		rs485conf->flags &= ~SER_RS485_RTS_AFTER_SEND;
1616 	} else {
1617 		rs485conf->flags &= ~SER_RS485_RTS_ON_SEND;
1618 		rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
1619 	}
1620 
1621 	/* check for tx enable gpio */
1622 	gflags = rs485conf->flags & SER_RS485_RTS_AFTER_SEND ?
1623 		GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
1624 	up->rts_gpiod = devm_gpiod_get_optional(dev, "rts", gflags);
1625 	if (IS_ERR(up->rts_gpiod)) {
1626 		ret = PTR_ERR(up->rts_gpiod);
1627 	        if (ret == -EPROBE_DEFER)
1628 			return ret;
1629 		/*
1630 		 * FIXME: the code historically ignored any other error than
1631 		 * -EPROBE_DEFER and just went on without GPIO.
1632 		 */
1633 		up->rts_gpiod = NULL;
1634 	} else {
1635 		gpiod_set_consumer_name(up->rts_gpiod, "omap-serial");
1636 	}
1637 
1638 	return 0;
1639 }
1640 
1641 static int serial_omap_probe(struct platform_device *pdev)
1642 {
1643 	struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
1644 	struct uart_omap_port *up;
1645 	struct resource *mem;
1646 	void __iomem *base;
1647 	int uartirq = 0;
1648 	int wakeirq = 0;
1649 	int ret;
1650 
1651 	/* The optional wakeirq may be specified in the board dts file */
1652 	if (pdev->dev.of_node) {
1653 		uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0);
1654 		if (!uartirq)
1655 			return -EPROBE_DEFER;
1656 		wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
1657 		omap_up_info = of_get_uart_port_info(&pdev->dev);
1658 		pdev->dev.platform_data = omap_up_info;
1659 	} else {
1660 		uartirq = platform_get_irq(pdev, 0);
1661 		if (uartirq < 0)
1662 			return -EPROBE_DEFER;
1663 	}
1664 
1665 	up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
1666 	if (!up)
1667 		return -ENOMEM;
1668 
1669 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1670 	base = devm_ioremap_resource(&pdev->dev, mem);
1671 	if (IS_ERR(base))
1672 		return PTR_ERR(base);
1673 
1674 	up->dev = &pdev->dev;
1675 	up->port.dev = &pdev->dev;
1676 	up->port.type = PORT_OMAP;
1677 	up->port.iotype = UPIO_MEM;
1678 	up->port.irq = uartirq;
1679 	up->port.regshift = 2;
1680 	up->port.fifosize = 64;
1681 	up->port.ops = &serial_omap_pops;
1682 	up->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_OMAP_CONSOLE);
1683 
1684 	if (pdev->dev.of_node)
1685 		ret = of_alias_get_id(pdev->dev.of_node, "serial");
1686 	else
1687 		ret = pdev->id;
1688 
1689 	if (ret < 0) {
1690 		dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1691 			ret);
1692 		goto err_port_line;
1693 	}
1694 	up->port.line = ret;
1695 
1696 	if (up->port.line >= OMAP_MAX_HSUART_PORTS) {
1697 		dev_err(&pdev->dev, "uart ID %d >  MAX %d.\n", up->port.line,
1698 			OMAP_MAX_HSUART_PORTS);
1699 		ret = -ENXIO;
1700 		goto err_port_line;
1701 	}
1702 
1703 	up->wakeirq = wakeirq;
1704 	if (!up->wakeirq)
1705 		dev_info(up->port.dev, "no wakeirq for uart%d\n",
1706 			 up->port.line);
1707 
1708 	ret = serial_omap_probe_rs485(up, &pdev->dev);
1709 	if (ret < 0)
1710 		goto err_rs485;
1711 
1712 	sprintf(up->name, "OMAP UART%d", up->port.line);
1713 	up->port.mapbase = mem->start;
1714 	up->port.membase = base;
1715 	up->port.flags = omap_up_info->flags;
1716 	up->port.uartclk = omap_up_info->uartclk;
1717 	up->port.rs485_config = serial_omap_config_rs485;
1718 	if (!up->port.uartclk) {
1719 		up->port.uartclk = DEFAULT_CLK_SPEED;
1720 		dev_warn(&pdev->dev,
1721 			 "No clock speed specified: using default: %d\n",
1722 			 DEFAULT_CLK_SPEED);
1723 	}
1724 
1725 	up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1726 	up->calc_latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1727 	cpu_latency_qos_add_request(&up->pm_qos_request, up->latency);
1728 	INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1729 
1730 	platform_set_drvdata(pdev, up);
1731 	if (omap_up_info->autosuspend_timeout == 0)
1732 		omap_up_info->autosuspend_timeout = -1;
1733 
1734 	device_init_wakeup(up->dev, true);
1735 	pm_runtime_use_autosuspend(&pdev->dev);
1736 	pm_runtime_set_autosuspend_delay(&pdev->dev,
1737 			omap_up_info->autosuspend_timeout);
1738 
1739 	pm_runtime_irq_safe(&pdev->dev);
1740 	pm_runtime_enable(&pdev->dev);
1741 
1742 	pm_runtime_get_sync(&pdev->dev);
1743 
1744 	omap_serial_fill_features_erratas(up);
1745 
1746 	ui[up->port.line] = up;
1747 	serial_omap_add_console_port(up);
1748 
1749 	ret = uart_add_one_port(&serial_omap_reg, &up->port);
1750 	if (ret != 0)
1751 		goto err_add_port;
1752 
1753 	pm_runtime_mark_last_busy(up->dev);
1754 	pm_runtime_put_autosuspend(up->dev);
1755 	return 0;
1756 
1757 err_add_port:
1758 	pm_runtime_dont_use_autosuspend(&pdev->dev);
1759 	pm_runtime_put_sync(&pdev->dev);
1760 	pm_runtime_disable(&pdev->dev);
1761 	cpu_latency_qos_remove_request(&up->pm_qos_request);
1762 	device_init_wakeup(up->dev, false);
1763 err_rs485:
1764 err_port_line:
1765 	return ret;
1766 }
1767 
1768 static int serial_omap_remove(struct platform_device *dev)
1769 {
1770 	struct uart_omap_port *up = platform_get_drvdata(dev);
1771 
1772 	pm_runtime_get_sync(up->dev);
1773 
1774 	uart_remove_one_port(&serial_omap_reg, &up->port);
1775 
1776 	pm_runtime_dont_use_autosuspend(up->dev);
1777 	pm_runtime_put_sync(up->dev);
1778 	pm_runtime_disable(up->dev);
1779 	cpu_latency_qos_remove_request(&up->pm_qos_request);
1780 	device_init_wakeup(&dev->dev, false);
1781 
1782 	return 0;
1783 }
1784 
1785 /*
1786  * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1787  * The access to uart register after MDR1 Access
1788  * causes UART to corrupt data.
1789  *
1790  * Need a delay =
1791  * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1792  * give 10 times as much
1793  */
1794 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1795 {
1796 	u8 timeout = 255;
1797 
1798 	serial_out(up, UART_OMAP_MDR1, mdr1);
1799 	udelay(2);
1800 	serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1801 			UART_FCR_CLEAR_RCVR);
1802 	/*
1803 	 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1804 	 * TX_FIFO_E bit is 1.
1805 	 */
1806 	while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1807 				(UART_LSR_THRE | UART_LSR_DR))) {
1808 		timeout--;
1809 		if (!timeout) {
1810 			/* Should *never* happen. we warn and carry on */
1811 			dev_crit(up->dev, "Errata i202: timedout %x\n",
1812 						serial_in(up, UART_LSR));
1813 			break;
1814 		}
1815 		udelay(1);
1816 	}
1817 }
1818 
1819 #ifdef CONFIG_PM
1820 static void serial_omap_restore_context(struct uart_omap_port *up)
1821 {
1822 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1823 		serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1824 	else
1825 		serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1826 
1827 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1828 	serial_out(up, UART_EFR, UART_EFR_ECB);
1829 	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1830 	serial_out(up, UART_IER, 0x0);
1831 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1832 	serial_out(up, UART_DLL, up->dll);
1833 	serial_out(up, UART_DLM, up->dlh);
1834 	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1835 	serial_out(up, UART_IER, up->ier);
1836 	serial_out(up, UART_FCR, up->fcr);
1837 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1838 	serial_out(up, UART_MCR, up->mcr);
1839 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1840 	serial_out(up, UART_OMAP_SCR, up->scr);
1841 	serial_out(up, UART_EFR, up->efr);
1842 	serial_out(up, UART_LCR, up->lcr);
1843 	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1844 		serial_omap_mdr1_errataset(up, up->mdr1);
1845 	else
1846 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1847 	serial_out(up, UART_OMAP_WER, up->wer);
1848 }
1849 
1850 static int serial_omap_runtime_suspend(struct device *dev)
1851 {
1852 	struct uart_omap_port *up = dev_get_drvdata(dev);
1853 
1854 	if (!up)
1855 		return -EINVAL;
1856 
1857 	/*
1858 	* When using 'no_console_suspend', the console UART must not be
1859 	* suspended. Since driver suspend is managed by runtime suspend,
1860 	* preventing runtime suspend (by returning error) will keep device
1861 	* active during suspend.
1862 	*/
1863 	if (up->is_suspending && !console_suspend_enabled &&
1864 	    uart_console(&up->port))
1865 		return -EBUSY;
1866 
1867 	up->context_loss_cnt = serial_omap_get_context_loss_count(up);
1868 
1869 	serial_omap_enable_wakeup(up, true);
1870 
1871 	up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1872 	schedule_work(&up->qos_work);
1873 
1874 	return 0;
1875 }
1876 
1877 static int serial_omap_runtime_resume(struct device *dev)
1878 {
1879 	struct uart_omap_port *up = dev_get_drvdata(dev);
1880 
1881 	int loss_cnt = serial_omap_get_context_loss_count(up);
1882 
1883 	serial_omap_enable_wakeup(up, false);
1884 
1885 	if (loss_cnt < 0) {
1886 		dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
1887 			loss_cnt);
1888 		serial_omap_restore_context(up);
1889 	} else if (up->context_loss_cnt != loss_cnt) {
1890 		serial_omap_restore_context(up);
1891 	}
1892 	up->latency = up->calc_latency;
1893 	schedule_work(&up->qos_work);
1894 
1895 	return 0;
1896 }
1897 #endif
1898 
1899 static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1900 	SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1901 	SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1902 				serial_omap_runtime_resume, NULL)
1903 	.prepare        = serial_omap_prepare,
1904 	.complete       = serial_omap_complete,
1905 };
1906 
1907 #if defined(CONFIG_OF)
1908 static const struct of_device_id omap_serial_of_match[] = {
1909 	{ .compatible = "ti,omap2-uart" },
1910 	{ .compatible = "ti,omap3-uart" },
1911 	{ .compatible = "ti,omap4-uart" },
1912 	{},
1913 };
1914 MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1915 #endif
1916 
1917 static struct platform_driver serial_omap_driver = {
1918 	.probe          = serial_omap_probe,
1919 	.remove         = serial_omap_remove,
1920 	.driver		= {
1921 		.name	= OMAP_SERIAL_DRIVER_NAME,
1922 		.pm	= &serial_omap_dev_pm_ops,
1923 		.of_match_table = of_match_ptr(omap_serial_of_match),
1924 	},
1925 };
1926 
1927 static int __init serial_omap_init(void)
1928 {
1929 	int ret;
1930 
1931 	ret = uart_register_driver(&serial_omap_reg);
1932 	if (ret != 0)
1933 		return ret;
1934 	ret = platform_driver_register(&serial_omap_driver);
1935 	if (ret != 0)
1936 		uart_unregister_driver(&serial_omap_reg);
1937 	return ret;
1938 }
1939 
1940 static void __exit serial_omap_exit(void)
1941 {
1942 	platform_driver_unregister(&serial_omap_driver);
1943 	uart_unregister_driver(&serial_omap_reg);
1944 }
1945 
1946 module_init(serial_omap_init);
1947 module_exit(serial_omap_exit);
1948 
1949 MODULE_DESCRIPTION("OMAP High Speed UART driver");
1950 MODULE_LICENSE("GPL");
1951 MODULE_AUTHOR("Texas Instruments Inc");
1952