1/*
2 * Driver for OMAP-UART controller.
3 * Based on drivers/serial/8250.c
4 *
5 * Copyright (C) 2010 Texas Instruments.
6 *
7 * Authors:
8 *	Govindraj R	<govindraj.raja@ti.com>
9 *	Thara Gopinath	<thara@ti.com>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * Note: This driver is made separate from 8250 driver as we cannot
17 * over load 8250 driver with omap platform specific configuration for
18 * features like DMA, it makes easier to implement features like DMA and
19 * hardware flow control and software flow control configuration with
20 * this driver as required for the omap-platform.
21 */
22
23#if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
24#define SUPPORT_SYSRQ
25#endif
26
27#include <linux/module.h>
28#include <linux/init.h>
29#include <linux/console.h>
30#include <linux/serial_reg.h>
31#include <linux/delay.h>
32#include <linux/slab.h>
33#include <linux/tty.h>
34#include <linux/tty_flip.h>
35#include <linux/platform_device.h>
36#include <linux/io.h>
37#include <linux/clk.h>
38#include <linux/serial_core.h>
39#include <linux/irq.h>
40#include <linux/pm_runtime.h>
41#include <linux/of.h>
42#include <linux/of_irq.h>
43#include <linux/gpio.h>
44#include <linux/of_gpio.h>
45#include <linux/platform_data/serial-omap.h>
46
47#include <dt-bindings/gpio/gpio.h>
48
49#define OMAP_MAX_HSUART_PORTS	10
50
51#define UART_BUILD_REVISION(x, y)	(((x) << 8) | (y))
52
53#define OMAP_UART_REV_42 0x0402
54#define OMAP_UART_REV_46 0x0406
55#define OMAP_UART_REV_52 0x0502
56#define OMAP_UART_REV_63 0x0603
57
58#define OMAP_UART_TX_WAKEUP_EN		BIT(7)
59
60/* Feature flags */
61#define OMAP_UART_WER_HAS_TX_WAKEUP	BIT(0)
62
63#define UART_ERRATA_i202_MDR1_ACCESS	BIT(0)
64#define UART_ERRATA_i291_DMA_FORCEIDLE	BIT(1)
65
66#define DEFAULT_CLK_SPEED 48000000 /* 48Mhz */
67
68/* SCR register bitmasks */
69#define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK		(1 << 7)
70#define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK		(1 << 6)
71#define OMAP_UART_SCR_TX_EMPTY			(1 << 3)
72
73/* FCR register bitmasks */
74#define OMAP_UART_FCR_RX_FIFO_TRIG_MASK			(0x3 << 6)
75#define OMAP_UART_FCR_TX_FIFO_TRIG_MASK			(0x3 << 4)
76
77/* MVR register bitmasks */
78#define OMAP_UART_MVR_SCHEME_SHIFT	30
79
80#define OMAP_UART_LEGACY_MVR_MAJ_MASK	0xf0
81#define OMAP_UART_LEGACY_MVR_MAJ_SHIFT	4
82#define OMAP_UART_LEGACY_MVR_MIN_MASK	0x0f
83
84#define OMAP_UART_MVR_MAJ_MASK		0x700
85#define OMAP_UART_MVR_MAJ_SHIFT		8
86#define OMAP_UART_MVR_MIN_MASK		0x3f
87
88#define OMAP_UART_DMA_CH_FREE	-1
89
90#define MSR_SAVE_FLAGS		UART_MSR_ANY_DELTA
91#define OMAP_MODE13X_SPEED	230400
92
93/* WER = 0x7F
94 * Enable module level wakeup in WER reg
95 */
96#define OMAP_UART_WER_MOD_WKUP	0x7F
97
98/* Enable XON/XOFF flow control on output */
99#define OMAP_UART_SW_TX		0x08
100
101/* Enable XON/XOFF flow control on input */
102#define OMAP_UART_SW_RX		0x02
103
104#define OMAP_UART_SW_CLR	0xF0
105
106#define OMAP_UART_TCR_TRIG	0x0F
107
108struct uart_omap_dma {
109	u8			uart_dma_tx;
110	u8			uart_dma_rx;
111	int			rx_dma_channel;
112	int			tx_dma_channel;
113	dma_addr_t		rx_buf_dma_phys;
114	dma_addr_t		tx_buf_dma_phys;
115	unsigned int		uart_base;
116	/*
117	 * Buffer for rx dma. It is not required for tx because the buffer
118	 * comes from port structure.
119	 */
120	unsigned char		*rx_buf;
121	unsigned int		prev_rx_dma_pos;
122	int			tx_buf_size;
123	int			tx_dma_used;
124	int			rx_dma_used;
125	spinlock_t		tx_lock;
126	spinlock_t		rx_lock;
127	/* timer to poll activity on rx dma */
128	struct timer_list	rx_timer;
129	unsigned int		rx_buf_size;
130	unsigned int		rx_poll_rate;
131	unsigned int		rx_timeout;
132};
133
134struct uart_omap_port {
135	struct uart_port	port;
136	struct uart_omap_dma	uart_dma;
137	struct device		*dev;
138	int			wakeirq;
139
140	unsigned char		ier;
141	unsigned char		lcr;
142	unsigned char		mcr;
143	unsigned char		fcr;
144	unsigned char		efr;
145	unsigned char		dll;
146	unsigned char		dlh;
147	unsigned char		mdr1;
148	unsigned char		scr;
149	unsigned char		wer;
150
151	int			use_dma;
152	/*
153	 * Some bits in registers are cleared on a read, so they must
154	 * be saved whenever the register is read, but the bits will not
155	 * be immediately processed.
156	 */
157	unsigned int		lsr_break_flag;
158	unsigned char		msr_saved_flags;
159	char			name[20];
160	unsigned long		port_activity;
161	int			context_loss_cnt;
162	u32			errata;
163	u8			wakeups_enabled;
164	u32			features;
165
166	int			rts_gpio;
167
168	struct pm_qos_request	pm_qos_request;
169	u32			latency;
170	u32			calc_latency;
171	struct work_struct	qos_work;
172	bool			is_suspending;
173};
174
175#define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
176
177static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
178
179/* Forward declaration of functions */
180static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
181
182static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
183{
184	offset <<= up->port.regshift;
185	return readw(up->port.membase + offset);
186}
187
188static inline void serial_out(struct uart_omap_port *up, int offset, int value)
189{
190	offset <<= up->port.regshift;
191	writew(value, up->port.membase + offset);
192}
193
194static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
195{
196	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
197	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
198		       UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
199	serial_out(up, UART_FCR, 0);
200}
201
202static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
203{
204	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
205
206	if (!pdata || !pdata->get_context_loss_count)
207		return -EINVAL;
208
209	return pdata->get_context_loss_count(up->dev);
210}
211
212static inline void serial_omap_enable_wakeirq(struct uart_omap_port *up,
213				       bool enable)
214{
215	if (!up->wakeirq)
216		return;
217
218	if (enable)
219		enable_irq(up->wakeirq);
220	else
221		disable_irq_nosync(up->wakeirq);
222}
223
224static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
225{
226	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
227
228	if (enable == up->wakeups_enabled)
229		return;
230
231	serial_omap_enable_wakeirq(up, enable);
232	up->wakeups_enabled = enable;
233
234	if (!pdata || !pdata->enable_wakeup)
235		return;
236
237	pdata->enable_wakeup(up->dev, enable);
238}
239
240/*
241 * Calculate the absolute difference between the desired and actual baud
242 * rate for the given mode.
243 */
244static inline int calculate_baud_abs_diff(struct uart_port *port,
245				unsigned int baud, unsigned int mode)
246{
247	unsigned int n = port->uartclk / (mode * baud);
248	int abs_diff;
249
250	if (n == 0)
251		n = 1;
252
253	abs_diff = baud - (port->uartclk / (mode * n));
254	if (abs_diff < 0)
255		abs_diff = -abs_diff;
256
257	return abs_diff;
258}
259
260/*
261 * serial_omap_baud_is_mode16 - check if baud rate is MODE16X
262 * @port: uart port info
263 * @baud: baudrate for which mode needs to be determined
264 *
265 * Returns true if baud rate is MODE16X and false if MODE13X
266 * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
267 * and Error Rates" determines modes not for all common baud rates.
268 * E.g. for 1000000 baud rate mode must be 16x, but according to that
269 * table it's determined as 13x.
270 */
271static bool
272serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
273{
274	int abs_diff_13 = calculate_baud_abs_diff(port, baud, 13);
275	int abs_diff_16 = calculate_baud_abs_diff(port, baud, 16);
276
277	return (abs_diff_13 >= abs_diff_16);
278}
279
280/*
281 * serial_omap_get_divisor - calculate divisor value
282 * @port: uart port info
283 * @baud: baudrate for which divisor needs to be calculated.
284 */
285static unsigned int
286serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
287{
288	unsigned int mode;
289
290	if (!serial_omap_baud_is_mode16(port, baud))
291		mode = 13;
292	else
293		mode = 16;
294	return port->uartclk/(mode * baud);
295}
296
297static void serial_omap_enable_ms(struct uart_port *port)
298{
299	struct uart_omap_port *up = to_uart_omap_port(port);
300
301	dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
302
303	pm_runtime_get_sync(up->dev);
304	up->ier |= UART_IER_MSI;
305	serial_out(up, UART_IER, up->ier);
306	pm_runtime_mark_last_busy(up->dev);
307	pm_runtime_put_autosuspend(up->dev);
308}
309
310static void serial_omap_stop_tx(struct uart_port *port)
311{
312	struct uart_omap_port *up = to_uart_omap_port(port);
313	int res;
314
315	pm_runtime_get_sync(up->dev);
316
317	/* Handle RS-485 */
318	if (port->rs485.flags & SER_RS485_ENABLED) {
319		if (up->scr & OMAP_UART_SCR_TX_EMPTY) {
320			/* THR interrupt is fired when both TX FIFO and TX
321			 * shift register are empty. This means there's nothing
322			 * left to transmit now, so make sure the THR interrupt
323			 * is fired when TX FIFO is below the trigger level,
324			 * disable THR interrupts and toggle the RS-485 GPIO
325			 * data direction pin if needed.
326			 */
327			up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
328			serial_out(up, UART_OMAP_SCR, up->scr);
329			res = (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) ?
330				1 : 0;
331			if (gpio_get_value(up->rts_gpio) != res) {
332				if (port->rs485.delay_rts_after_send > 0)
333					mdelay(
334					port->rs485.delay_rts_after_send);
335				gpio_set_value(up->rts_gpio, res);
336			}
337		} else {
338			/* We're asked to stop, but there's still stuff in the
339			 * UART FIFO, so make sure the THR interrupt is fired
340			 * when both TX FIFO and TX shift register are empty.
341			 * The next THR interrupt (if no transmission is started
342			 * in the meantime) will indicate the end of a
343			 * transmission. Therefore we _don't_ disable THR
344			 * interrupts in this situation.
345			 */
346			up->scr |= OMAP_UART_SCR_TX_EMPTY;
347			serial_out(up, UART_OMAP_SCR, up->scr);
348			return;
349		}
350	}
351
352	if (up->ier & UART_IER_THRI) {
353		up->ier &= ~UART_IER_THRI;
354		serial_out(up, UART_IER, up->ier);
355	}
356
357	if ((port->rs485.flags & SER_RS485_ENABLED) &&
358	    !(port->rs485.flags & SER_RS485_RX_DURING_TX)) {
359		/*
360		 * Empty the RX FIFO, we are not interested in anything
361		 * received during the half-duplex transmission.
362		 */
363		serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_RCVR);
364		/* Re-enable RX interrupts */
365		up->ier |= UART_IER_RLSI | UART_IER_RDI;
366		up->port.read_status_mask |= UART_LSR_DR;
367		serial_out(up, UART_IER, up->ier);
368	}
369
370	pm_runtime_mark_last_busy(up->dev);
371	pm_runtime_put_autosuspend(up->dev);
372}
373
374static void serial_omap_stop_rx(struct uart_port *port)
375{
376	struct uart_omap_port *up = to_uart_omap_port(port);
377
378	pm_runtime_get_sync(up->dev);
379	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
380	up->port.read_status_mask &= ~UART_LSR_DR;
381	serial_out(up, UART_IER, up->ier);
382	pm_runtime_mark_last_busy(up->dev);
383	pm_runtime_put_autosuspend(up->dev);
384}
385
386static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
387{
388	struct circ_buf *xmit = &up->port.state->xmit;
389	int count;
390
391	if (up->port.x_char) {
392		serial_out(up, UART_TX, up->port.x_char);
393		up->port.icount.tx++;
394		up->port.x_char = 0;
395		return;
396	}
397	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
398		serial_omap_stop_tx(&up->port);
399		return;
400	}
401	count = up->port.fifosize / 4;
402	do {
403		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
404		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
405		up->port.icount.tx++;
406		if (uart_circ_empty(xmit))
407			break;
408	} while (--count > 0);
409
410	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
411		uart_write_wakeup(&up->port);
412
413	if (uart_circ_empty(xmit))
414		serial_omap_stop_tx(&up->port);
415}
416
417static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
418{
419	if (!(up->ier & UART_IER_THRI)) {
420		up->ier |= UART_IER_THRI;
421		serial_out(up, UART_IER, up->ier);
422	}
423}
424
425static void serial_omap_start_tx(struct uart_port *port)
426{
427	struct uart_omap_port *up = to_uart_omap_port(port);
428	int res;
429
430	pm_runtime_get_sync(up->dev);
431
432	/* Handle RS-485 */
433	if (port->rs485.flags & SER_RS485_ENABLED) {
434		/* Fire THR interrupts when FIFO is below trigger level */
435		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
436		serial_out(up, UART_OMAP_SCR, up->scr);
437
438		/* if rts not already enabled */
439		res = (port->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
440		if (gpio_get_value(up->rts_gpio) != res) {
441			gpio_set_value(up->rts_gpio, res);
442			if (port->rs485.delay_rts_before_send > 0)
443				mdelay(port->rs485.delay_rts_before_send);
444		}
445	}
446
447	if ((port->rs485.flags & SER_RS485_ENABLED) &&
448	    !(port->rs485.flags & SER_RS485_RX_DURING_TX))
449		serial_omap_stop_rx(port);
450
451	serial_omap_enable_ier_thri(up);
452	pm_runtime_mark_last_busy(up->dev);
453	pm_runtime_put_autosuspend(up->dev);
454}
455
456static void serial_omap_throttle(struct uart_port *port)
457{
458	struct uart_omap_port *up = to_uart_omap_port(port);
459	unsigned long flags;
460
461	pm_runtime_get_sync(up->dev);
462	spin_lock_irqsave(&up->port.lock, flags);
463	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
464	serial_out(up, UART_IER, up->ier);
465	spin_unlock_irqrestore(&up->port.lock, flags);
466	pm_runtime_mark_last_busy(up->dev);
467	pm_runtime_put_autosuspend(up->dev);
468}
469
470static void serial_omap_unthrottle(struct uart_port *port)
471{
472	struct uart_omap_port *up = to_uart_omap_port(port);
473	unsigned long flags;
474
475	pm_runtime_get_sync(up->dev);
476	spin_lock_irqsave(&up->port.lock, flags);
477	up->ier |= UART_IER_RLSI | UART_IER_RDI;
478	serial_out(up, UART_IER, up->ier);
479	spin_unlock_irqrestore(&up->port.lock, flags);
480	pm_runtime_mark_last_busy(up->dev);
481	pm_runtime_put_autosuspend(up->dev);
482}
483
484static unsigned int check_modem_status(struct uart_omap_port *up)
485{
486	unsigned int status;
487
488	status = serial_in(up, UART_MSR);
489	status |= up->msr_saved_flags;
490	up->msr_saved_flags = 0;
491	if ((status & UART_MSR_ANY_DELTA) == 0)
492		return status;
493
494	if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
495	    up->port.state != NULL) {
496		if (status & UART_MSR_TERI)
497			up->port.icount.rng++;
498		if (status & UART_MSR_DDSR)
499			up->port.icount.dsr++;
500		if (status & UART_MSR_DDCD)
501			uart_handle_dcd_change
502				(&up->port, status & UART_MSR_DCD);
503		if (status & UART_MSR_DCTS)
504			uart_handle_cts_change
505				(&up->port, status & UART_MSR_CTS);
506		wake_up_interruptible(&up->port.state->port.delta_msr_wait);
507	}
508
509	return status;
510}
511
512static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
513{
514	unsigned int flag;
515	unsigned char ch = 0;
516
517	if (likely(lsr & UART_LSR_DR))
518		ch = serial_in(up, UART_RX);
519
520	up->port.icount.rx++;
521	flag = TTY_NORMAL;
522
523	if (lsr & UART_LSR_BI) {
524		flag = TTY_BREAK;
525		lsr &= ~(UART_LSR_FE | UART_LSR_PE);
526		up->port.icount.brk++;
527		/*
528		 * We do the SysRQ and SAK checking
529		 * here because otherwise the break
530		 * may get masked by ignore_status_mask
531		 * or read_status_mask.
532		 */
533		if (uart_handle_break(&up->port))
534			return;
535
536	}
537
538	if (lsr & UART_LSR_PE) {
539		flag = TTY_PARITY;
540		up->port.icount.parity++;
541	}
542
543	if (lsr & UART_LSR_FE) {
544		flag = TTY_FRAME;
545		up->port.icount.frame++;
546	}
547
548	if (lsr & UART_LSR_OE)
549		up->port.icount.overrun++;
550
551#ifdef CONFIG_SERIAL_OMAP_CONSOLE
552	if (up->port.line == up->port.cons->index) {
553		/* Recover the break flag from console xmit */
554		lsr |= up->lsr_break_flag;
555	}
556#endif
557	uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag);
558}
559
560static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
561{
562	unsigned char ch = 0;
563	unsigned int flag;
564
565	if (!(lsr & UART_LSR_DR))
566		return;
567
568	ch = serial_in(up, UART_RX);
569	flag = TTY_NORMAL;
570	up->port.icount.rx++;
571
572	if (uart_handle_sysrq_char(&up->port, ch))
573		return;
574
575	uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
576}
577
578/**
579 * serial_omap_irq() - This handles the interrupt from one port
580 * @irq: uart port irq number
581 * @dev_id: uart port info
582 */
583static irqreturn_t serial_omap_irq(int irq, void *dev_id)
584{
585	struct uart_omap_port *up = dev_id;
586	unsigned int iir, lsr;
587	unsigned int type;
588	irqreturn_t ret = IRQ_NONE;
589	int max_count = 256;
590
591	spin_lock(&up->port.lock);
592	pm_runtime_get_sync(up->dev);
593
594	do {
595		iir = serial_in(up, UART_IIR);
596		if (iir & UART_IIR_NO_INT)
597			break;
598
599		ret = IRQ_HANDLED;
600		lsr = serial_in(up, UART_LSR);
601
602		/* extract IRQ type from IIR register */
603		type = iir & 0x3e;
604
605		switch (type) {
606		case UART_IIR_MSI:
607			check_modem_status(up);
608			break;
609		case UART_IIR_THRI:
610			transmit_chars(up, lsr);
611			break;
612		case UART_IIR_RX_TIMEOUT:
613			/* FALLTHROUGH */
614		case UART_IIR_RDI:
615			serial_omap_rdi(up, lsr);
616			break;
617		case UART_IIR_RLSI:
618			serial_omap_rlsi(up, lsr);
619			break;
620		case UART_IIR_CTS_RTS_DSR:
621			/* simply try again */
622			break;
623		case UART_IIR_XOFF:
624			/* FALLTHROUGH */
625		default:
626			break;
627		}
628	} while (!(iir & UART_IIR_NO_INT) && max_count--);
629
630	spin_unlock(&up->port.lock);
631
632	tty_flip_buffer_push(&up->port.state->port);
633
634	pm_runtime_mark_last_busy(up->dev);
635	pm_runtime_put_autosuspend(up->dev);
636	up->port_activity = jiffies;
637
638	return ret;
639}
640
641static unsigned int serial_omap_tx_empty(struct uart_port *port)
642{
643	struct uart_omap_port *up = to_uart_omap_port(port);
644	unsigned long flags = 0;
645	unsigned int ret = 0;
646
647	pm_runtime_get_sync(up->dev);
648	dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
649	spin_lock_irqsave(&up->port.lock, flags);
650	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
651	spin_unlock_irqrestore(&up->port.lock, flags);
652	pm_runtime_mark_last_busy(up->dev);
653	pm_runtime_put_autosuspend(up->dev);
654	return ret;
655}
656
657static unsigned int serial_omap_get_mctrl(struct uart_port *port)
658{
659	struct uart_omap_port *up = to_uart_omap_port(port);
660	unsigned int status;
661	unsigned int ret = 0;
662
663	pm_runtime_get_sync(up->dev);
664	status = check_modem_status(up);
665	pm_runtime_mark_last_busy(up->dev);
666	pm_runtime_put_autosuspend(up->dev);
667
668	dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
669
670	if (status & UART_MSR_DCD)
671		ret |= TIOCM_CAR;
672	if (status & UART_MSR_RI)
673		ret |= TIOCM_RNG;
674	if (status & UART_MSR_DSR)
675		ret |= TIOCM_DSR;
676	if (status & UART_MSR_CTS)
677		ret |= TIOCM_CTS;
678	return ret;
679}
680
681static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
682{
683	struct uart_omap_port *up = to_uart_omap_port(port);
684	unsigned char mcr = 0, old_mcr, lcr;
685
686	dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
687	if (mctrl & TIOCM_RTS)
688		mcr |= UART_MCR_RTS;
689	if (mctrl & TIOCM_DTR)
690		mcr |= UART_MCR_DTR;
691	if (mctrl & TIOCM_OUT1)
692		mcr |= UART_MCR_OUT1;
693	if (mctrl & TIOCM_OUT2)
694		mcr |= UART_MCR_OUT2;
695	if (mctrl & TIOCM_LOOP)
696		mcr |= UART_MCR_LOOP;
697
698	pm_runtime_get_sync(up->dev);
699	old_mcr = serial_in(up, UART_MCR);
700	old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
701		     UART_MCR_DTR | UART_MCR_RTS);
702	up->mcr = old_mcr | mcr;
703	serial_out(up, UART_MCR, up->mcr);
704
705	/* Turn off autoRTS if RTS is lowered; restore autoRTS if RTS raised */
706	lcr = serial_in(up, UART_LCR);
707	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
708	if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS))
709		up->efr |= UART_EFR_RTS;
710	else
711		up->efr &= UART_EFR_RTS;
712	serial_out(up, UART_EFR, up->efr);
713	serial_out(up, UART_LCR, lcr);
714
715	pm_runtime_mark_last_busy(up->dev);
716	pm_runtime_put_autosuspend(up->dev);
717}
718
719static void serial_omap_break_ctl(struct uart_port *port, int break_state)
720{
721	struct uart_omap_port *up = to_uart_omap_port(port);
722	unsigned long flags = 0;
723
724	dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
725	pm_runtime_get_sync(up->dev);
726	spin_lock_irqsave(&up->port.lock, flags);
727	if (break_state == -1)
728		up->lcr |= UART_LCR_SBC;
729	else
730		up->lcr &= ~UART_LCR_SBC;
731	serial_out(up, UART_LCR, up->lcr);
732	spin_unlock_irqrestore(&up->port.lock, flags);
733	pm_runtime_mark_last_busy(up->dev);
734	pm_runtime_put_autosuspend(up->dev);
735}
736
737static int serial_omap_startup(struct uart_port *port)
738{
739	struct uart_omap_port *up = to_uart_omap_port(port);
740	unsigned long flags = 0;
741	int retval;
742
743	/*
744	 * Allocate the IRQ
745	 */
746	retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
747				up->name, up);
748	if (retval)
749		return retval;
750
751	/* Optional wake-up IRQ */
752	if (up->wakeirq) {
753		retval = request_irq(up->wakeirq, serial_omap_irq,
754				     up->port.irqflags, up->name, up);
755		if (retval) {
756			free_irq(up->port.irq, up);
757			return retval;
758		}
759		disable_irq(up->wakeirq);
760	}
761
762	dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
763
764	pm_runtime_get_sync(up->dev);
765	/*
766	 * Clear the FIFO buffers and disable them.
767	 * (they will be reenabled in set_termios())
768	 */
769	serial_omap_clear_fifos(up);
770
771	/*
772	 * Clear the interrupt registers.
773	 */
774	(void) serial_in(up, UART_LSR);
775	if (serial_in(up, UART_LSR) & UART_LSR_DR)
776		(void) serial_in(up, UART_RX);
777	(void) serial_in(up, UART_IIR);
778	(void) serial_in(up, UART_MSR);
779
780	/*
781	 * Now, initialize the UART
782	 */
783	serial_out(up, UART_LCR, UART_LCR_WLEN8);
784	spin_lock_irqsave(&up->port.lock, flags);
785	/*
786	 * Most PC uarts need OUT2 raised to enable interrupts.
787	 */
788	up->port.mctrl |= TIOCM_OUT2;
789	serial_omap_set_mctrl(&up->port, up->port.mctrl);
790	spin_unlock_irqrestore(&up->port.lock, flags);
791
792	up->msr_saved_flags = 0;
793	/*
794	 * Finally, enable interrupts. Note: Modem status interrupts
795	 * are set via set_termios(), which will be occurring imminently
796	 * anyway, so we don't enable them here.
797	 */
798	up->ier = UART_IER_RLSI | UART_IER_RDI;
799	serial_out(up, UART_IER, up->ier);
800
801	/* Enable module level wake up */
802	up->wer = OMAP_UART_WER_MOD_WKUP;
803	if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
804		up->wer |= OMAP_UART_TX_WAKEUP_EN;
805
806	serial_out(up, UART_OMAP_WER, up->wer);
807
808	pm_runtime_mark_last_busy(up->dev);
809	pm_runtime_put_autosuspend(up->dev);
810	up->port_activity = jiffies;
811	return 0;
812}
813
814static void serial_omap_shutdown(struct uart_port *port)
815{
816	struct uart_omap_port *up = to_uart_omap_port(port);
817	unsigned long flags = 0;
818
819	dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
820
821	pm_runtime_get_sync(up->dev);
822	/*
823	 * Disable interrupts from this port
824	 */
825	up->ier = 0;
826	serial_out(up, UART_IER, 0);
827
828	spin_lock_irqsave(&up->port.lock, flags);
829	up->port.mctrl &= ~TIOCM_OUT2;
830	serial_omap_set_mctrl(&up->port, up->port.mctrl);
831	spin_unlock_irqrestore(&up->port.lock, flags);
832
833	/*
834	 * Disable break condition and FIFOs
835	 */
836	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
837	serial_omap_clear_fifos(up);
838
839	/*
840	 * Read data port to reset things, and then free the irq
841	 */
842	if (serial_in(up, UART_LSR) & UART_LSR_DR)
843		(void) serial_in(up, UART_RX);
844
845	pm_runtime_mark_last_busy(up->dev);
846	pm_runtime_put_autosuspend(up->dev);
847	free_irq(up->port.irq, up);
848	if (up->wakeirq)
849		free_irq(up->wakeirq, up);
850}
851
852static void serial_omap_uart_qos_work(struct work_struct *work)
853{
854	struct uart_omap_port *up = container_of(work, struct uart_omap_port,
855						qos_work);
856
857	pm_qos_update_request(&up->pm_qos_request, up->latency);
858}
859
860static void
861serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
862			struct ktermios *old)
863{
864	struct uart_omap_port *up = to_uart_omap_port(port);
865	unsigned char cval = 0;
866	unsigned long flags = 0;
867	unsigned int baud, quot;
868
869	switch (termios->c_cflag & CSIZE) {
870	case CS5:
871		cval = UART_LCR_WLEN5;
872		break;
873	case CS6:
874		cval = UART_LCR_WLEN6;
875		break;
876	case CS7:
877		cval = UART_LCR_WLEN7;
878		break;
879	default:
880	case CS8:
881		cval = UART_LCR_WLEN8;
882		break;
883	}
884
885	if (termios->c_cflag & CSTOPB)
886		cval |= UART_LCR_STOP;
887	if (termios->c_cflag & PARENB)
888		cval |= UART_LCR_PARITY;
889	if (!(termios->c_cflag & PARODD))
890		cval |= UART_LCR_EPAR;
891	if (termios->c_cflag & CMSPAR)
892		cval |= UART_LCR_SPAR;
893
894	/*
895	 * Ask the core to calculate the divisor for us.
896	 */
897
898	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
899	quot = serial_omap_get_divisor(port, baud);
900
901	/* calculate wakeup latency constraint */
902	up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
903	up->latency = up->calc_latency;
904	schedule_work(&up->qos_work);
905
906	up->dll = quot & 0xff;
907	up->dlh = quot >> 8;
908	up->mdr1 = UART_OMAP_MDR1_DISABLE;
909
910	up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
911			UART_FCR_ENABLE_FIFO;
912
913	/*
914	 * Ok, we're now changing the port state. Do it with
915	 * interrupts disabled.
916	 */
917	pm_runtime_get_sync(up->dev);
918	spin_lock_irqsave(&up->port.lock, flags);
919
920	/*
921	 * Update the per-port timeout.
922	 */
923	uart_update_timeout(port, termios->c_cflag, baud);
924
925	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
926	if (termios->c_iflag & INPCK)
927		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
928	if (termios->c_iflag & (BRKINT | PARMRK))
929		up->port.read_status_mask |= UART_LSR_BI;
930
931	/*
932	 * Characters to ignore
933	 */
934	up->port.ignore_status_mask = 0;
935	if (termios->c_iflag & IGNPAR)
936		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
937	if (termios->c_iflag & IGNBRK) {
938		up->port.ignore_status_mask |= UART_LSR_BI;
939		/*
940		 * If we're ignoring parity and break indicators,
941		 * ignore overruns too (for real raw support).
942		 */
943		if (termios->c_iflag & IGNPAR)
944			up->port.ignore_status_mask |= UART_LSR_OE;
945	}
946
947	/*
948	 * ignore all characters if CREAD is not set
949	 */
950	if ((termios->c_cflag & CREAD) == 0)
951		up->port.ignore_status_mask |= UART_LSR_DR;
952
953	/*
954	 * Modem status interrupts
955	 */
956	up->ier &= ~UART_IER_MSI;
957	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
958		up->ier |= UART_IER_MSI;
959	serial_out(up, UART_IER, up->ier);
960	serial_out(up, UART_LCR, cval);		/* reset DLAB */
961	up->lcr = cval;
962	up->scr = 0;
963
964	/* FIFOs and DMA Settings */
965
966	/* FCR can be changed only when the
967	 * baud clock is not running
968	 * DLL_REG and DLH_REG set to 0.
969	 */
970	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
971	serial_out(up, UART_DLL, 0);
972	serial_out(up, UART_DLM, 0);
973	serial_out(up, UART_LCR, 0);
974
975	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
976
977	up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
978	up->efr &= ~UART_EFR_SCD;
979	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
980
981	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
982	up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
983	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
984	/* FIFO ENABLE, DMA MODE */
985
986	up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
987	/*
988	 * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
989	 * sets Enables the granularity of 1 for TRIGGER RX
990	 * level. Along with setting RX FIFO trigger level
991	 * to 1 (as noted below, 16 characters) and TLR[3:0]
992	 * to zero this will result RX FIFO threshold level
993	 * to 1 character, instead of 16 as noted in comment
994	 * below.
995	 */
996
997	/* Set receive FIFO threshold to 16 characters and
998	 * transmit FIFO threshold to 32 spaces
999	 */
1000	up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
1001	up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
1002	up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
1003		UART_FCR_ENABLE_FIFO;
1004
1005	serial_out(up, UART_FCR, up->fcr);
1006	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1007
1008	serial_out(up, UART_OMAP_SCR, up->scr);
1009
1010	/* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
1011	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1012	serial_out(up, UART_MCR, up->mcr);
1013	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1014	serial_out(up, UART_EFR, up->efr);
1015	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1016
1017	/* Protocol, Baud Rate, and Interrupt Settings */
1018
1019	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1020		serial_omap_mdr1_errataset(up, up->mdr1);
1021	else
1022		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1023
1024	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1025	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1026
1027	serial_out(up, UART_LCR, 0);
1028	serial_out(up, UART_IER, 0);
1029	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1030
1031	serial_out(up, UART_DLL, up->dll);	/* LS of divisor */
1032	serial_out(up, UART_DLM, up->dlh);	/* MS of divisor */
1033
1034	serial_out(up, UART_LCR, 0);
1035	serial_out(up, UART_IER, up->ier);
1036	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1037
1038	serial_out(up, UART_EFR, up->efr);
1039	serial_out(up, UART_LCR, cval);
1040
1041	if (!serial_omap_baud_is_mode16(port, baud))
1042		up->mdr1 = UART_OMAP_MDR1_13X_MODE;
1043	else
1044		up->mdr1 = UART_OMAP_MDR1_16X_MODE;
1045
1046	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1047		serial_omap_mdr1_errataset(up, up->mdr1);
1048	else
1049		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1050
1051	/* Configure flow control */
1052	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1053
1054	/* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
1055	serial_out(up, UART_XON1, termios->c_cc[VSTART]);
1056	serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
1057
1058	/* Enable access to TCR/TLR */
1059	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1060	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1061	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
1062
1063	serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
1064
1065	up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
1066
1067	if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
1068		/* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */
1069		up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
1070		up->efr |= UART_EFR_CTS;
1071	} else {
1072		/* Disable AUTORTS and AUTOCTS */
1073		up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
1074	}
1075
1076	if (up->port.flags & UPF_SOFT_FLOW) {
1077		/* clear SW control mode bits */
1078		up->efr &= OMAP_UART_SW_CLR;
1079
1080		/*
1081		 * IXON Flag:
1082		 * Enable XON/XOFF flow control on input.
1083		 * Receiver compares XON1, XOFF1.
1084		 */
1085		if (termios->c_iflag & IXON)
1086			up->efr |= OMAP_UART_SW_RX;
1087
1088		/*
1089		 * IXOFF Flag:
1090		 * Enable XON/XOFF flow control on output.
1091		 * Transmit XON1, XOFF1
1092		 */
1093		if (termios->c_iflag & IXOFF) {
1094			up->port.status |= UPSTAT_AUTOXOFF;
1095			up->efr |= OMAP_UART_SW_TX;
1096		}
1097
1098		/*
1099		 * IXANY Flag:
1100		 * Enable any character to restart output.
1101		 * Operation resumes after receiving any
1102		 * character after recognition of the XOFF character
1103		 */
1104		if (termios->c_iflag & IXANY)
1105			up->mcr |= UART_MCR_XONANY;
1106		else
1107			up->mcr &= ~UART_MCR_XONANY;
1108	}
1109	serial_out(up, UART_MCR, up->mcr);
1110	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1111	serial_out(up, UART_EFR, up->efr);
1112	serial_out(up, UART_LCR, up->lcr);
1113
1114	serial_omap_set_mctrl(&up->port, up->port.mctrl);
1115
1116	spin_unlock_irqrestore(&up->port.lock, flags);
1117	pm_runtime_mark_last_busy(up->dev);
1118	pm_runtime_put_autosuspend(up->dev);
1119	dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
1120}
1121
1122static void
1123serial_omap_pm(struct uart_port *port, unsigned int state,
1124	       unsigned int oldstate)
1125{
1126	struct uart_omap_port *up = to_uart_omap_port(port);
1127	unsigned char efr;
1128
1129	dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
1130
1131	pm_runtime_get_sync(up->dev);
1132	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1133	efr = serial_in(up, UART_EFR);
1134	serial_out(up, UART_EFR, efr | UART_EFR_ECB);
1135	serial_out(up, UART_LCR, 0);
1136
1137	serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
1138	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1139	serial_out(up, UART_EFR, efr);
1140	serial_out(up, UART_LCR, 0);
1141
1142	if (!device_may_wakeup(up->dev)) {
1143		if (!state)
1144			pm_runtime_forbid(up->dev);
1145		else
1146			pm_runtime_allow(up->dev);
1147	}
1148
1149	pm_runtime_mark_last_busy(up->dev);
1150	pm_runtime_put_autosuspend(up->dev);
1151}
1152
1153static void serial_omap_release_port(struct uart_port *port)
1154{
1155	dev_dbg(port->dev, "serial_omap_release_port+\n");
1156}
1157
1158static int serial_omap_request_port(struct uart_port *port)
1159{
1160	dev_dbg(port->dev, "serial_omap_request_port+\n");
1161	return 0;
1162}
1163
1164static void serial_omap_config_port(struct uart_port *port, int flags)
1165{
1166	struct uart_omap_port *up = to_uart_omap_port(port);
1167
1168	dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
1169							up->port.line);
1170	up->port.type = PORT_OMAP;
1171	up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
1172}
1173
1174static int
1175serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
1176{
1177	/* we don't want the core code to modify any port params */
1178	dev_dbg(port->dev, "serial_omap_verify_port+\n");
1179	return -EINVAL;
1180}
1181
1182static const char *
1183serial_omap_type(struct uart_port *port)
1184{
1185	struct uart_omap_port *up = to_uart_omap_port(port);
1186
1187	dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
1188	return up->name;
1189}
1190
1191#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1192
1193static inline void wait_for_xmitr(struct uart_omap_port *up)
1194{
1195	unsigned int status, tmout = 10000;
1196
1197	/* Wait up to 10ms for the character(s) to be sent. */
1198	do {
1199		status = serial_in(up, UART_LSR);
1200
1201		if (status & UART_LSR_BI)
1202			up->lsr_break_flag = UART_LSR_BI;
1203
1204		if (--tmout == 0)
1205			break;
1206		udelay(1);
1207	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
1208
1209	/* Wait up to 1s for flow control if necessary */
1210	if (up->port.flags & UPF_CONS_FLOW) {
1211		tmout = 1000000;
1212		for (tmout = 1000000; tmout; tmout--) {
1213			unsigned int msr = serial_in(up, UART_MSR);
1214
1215			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1216			if (msr & UART_MSR_CTS)
1217				break;
1218
1219			udelay(1);
1220		}
1221	}
1222}
1223
1224#ifdef CONFIG_CONSOLE_POLL
1225
1226static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
1227{
1228	struct uart_omap_port *up = to_uart_omap_port(port);
1229
1230	pm_runtime_get_sync(up->dev);
1231	wait_for_xmitr(up);
1232	serial_out(up, UART_TX, ch);
1233	pm_runtime_mark_last_busy(up->dev);
1234	pm_runtime_put_autosuspend(up->dev);
1235}
1236
1237static int serial_omap_poll_get_char(struct uart_port *port)
1238{
1239	struct uart_omap_port *up = to_uart_omap_port(port);
1240	unsigned int status;
1241
1242	pm_runtime_get_sync(up->dev);
1243	status = serial_in(up, UART_LSR);
1244	if (!(status & UART_LSR_DR)) {
1245		status = NO_POLL_CHAR;
1246		goto out;
1247	}
1248
1249	status = serial_in(up, UART_RX);
1250
1251out:
1252	pm_runtime_mark_last_busy(up->dev);
1253	pm_runtime_put_autosuspend(up->dev);
1254
1255	return status;
1256}
1257
1258#endif /* CONFIG_CONSOLE_POLL */
1259
1260#ifdef CONFIG_SERIAL_OMAP_CONSOLE
1261
1262static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
1263
1264static struct uart_driver serial_omap_reg;
1265
1266static void serial_omap_console_putchar(struct uart_port *port, int ch)
1267{
1268	struct uart_omap_port *up = to_uart_omap_port(port);
1269
1270	wait_for_xmitr(up);
1271	serial_out(up, UART_TX, ch);
1272}
1273
1274static void
1275serial_omap_console_write(struct console *co, const char *s,
1276		unsigned int count)
1277{
1278	struct uart_omap_port *up = serial_omap_console_ports[co->index];
1279	unsigned long flags;
1280	unsigned int ier;
1281	int locked = 1;
1282
1283	pm_runtime_get_sync(up->dev);
1284
1285	local_irq_save(flags);
1286	if (up->port.sysrq)
1287		locked = 0;
1288	else if (oops_in_progress)
1289		locked = spin_trylock(&up->port.lock);
1290	else
1291		spin_lock(&up->port.lock);
1292
1293	/*
1294	 * First save the IER then disable the interrupts
1295	 */
1296	ier = serial_in(up, UART_IER);
1297	serial_out(up, UART_IER, 0);
1298
1299	uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1300
1301	/*
1302	 * Finally, wait for transmitter to become empty
1303	 * and restore the IER
1304	 */
1305	wait_for_xmitr(up);
1306	serial_out(up, UART_IER, ier);
1307	/*
1308	 * The receive handling will happen properly because the
1309	 * receive ready bit will still be set; it is not cleared
1310	 * on read.  However, modem control will not, we must
1311	 * call it if we have saved something in the saved flags
1312	 * while processing with interrupts off.
1313	 */
1314	if (up->msr_saved_flags)
1315		check_modem_status(up);
1316
1317	pm_runtime_mark_last_busy(up->dev);
1318	pm_runtime_put_autosuspend(up->dev);
1319	if (locked)
1320		spin_unlock(&up->port.lock);
1321	local_irq_restore(flags);
1322}
1323
1324static int __init
1325serial_omap_console_setup(struct console *co, char *options)
1326{
1327	struct uart_omap_port *up;
1328	int baud = 115200;
1329	int bits = 8;
1330	int parity = 'n';
1331	int flow = 'n';
1332
1333	if (serial_omap_console_ports[co->index] == NULL)
1334		return -ENODEV;
1335	up = serial_omap_console_ports[co->index];
1336
1337	if (options)
1338		uart_parse_options(options, &baud, &parity, &bits, &flow);
1339
1340	return uart_set_options(&up->port, co, baud, parity, bits, flow);
1341}
1342
1343static struct console serial_omap_console = {
1344	.name		= OMAP_SERIAL_NAME,
1345	.write		= serial_omap_console_write,
1346	.device		= uart_console_device,
1347	.setup		= serial_omap_console_setup,
1348	.flags		= CON_PRINTBUFFER,
1349	.index		= -1,
1350	.data		= &serial_omap_reg,
1351};
1352
1353static void serial_omap_add_console_port(struct uart_omap_port *up)
1354{
1355	serial_omap_console_ports[up->port.line] = up;
1356}
1357
1358#define OMAP_CONSOLE	(&serial_omap_console)
1359
1360#else
1361
1362#define OMAP_CONSOLE	NULL
1363
1364static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1365{}
1366
1367#endif
1368
1369/* Enable or disable the rs485 support */
1370static int
1371serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485)
1372{
1373	struct uart_omap_port *up = to_uart_omap_port(port);
1374	unsigned int mode;
1375	int val;
1376
1377	pm_runtime_get_sync(up->dev);
1378
1379	/* Disable interrupts from this port */
1380	mode = up->ier;
1381	up->ier = 0;
1382	serial_out(up, UART_IER, 0);
1383
1384	/* Clamp the delays to [0, 100ms] */
1385	rs485->delay_rts_before_send = min(rs485->delay_rts_before_send, 100U);
1386	rs485->delay_rts_after_send  = min(rs485->delay_rts_after_send, 100U);
1387
1388	/* store new config */
1389	port->rs485 = *rs485;
1390
1391	/*
1392	 * Just as a precaution, only allow rs485
1393	 * to be enabled if the gpio pin is valid
1394	 */
1395	if (gpio_is_valid(up->rts_gpio)) {
1396		/* enable / disable rts */
1397		val = (port->rs485.flags & SER_RS485_ENABLED) ?
1398			SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
1399		val = (port->rs485.flags & val) ? 1 : 0;
1400		gpio_set_value(up->rts_gpio, val);
1401	} else
1402		port->rs485.flags &= ~SER_RS485_ENABLED;
1403
1404	/* Enable interrupts */
1405	up->ier = mode;
1406	serial_out(up, UART_IER, up->ier);
1407
1408	/* If RS-485 is disabled, make sure the THR interrupt is fired when
1409	 * TX FIFO is below the trigger level.
1410	 */
1411	if (!(port->rs485.flags & SER_RS485_ENABLED) &&
1412	    (up->scr & OMAP_UART_SCR_TX_EMPTY)) {
1413		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
1414		serial_out(up, UART_OMAP_SCR, up->scr);
1415	}
1416
1417	pm_runtime_mark_last_busy(up->dev);
1418	pm_runtime_put_autosuspend(up->dev);
1419
1420	return 0;
1421}
1422
1423static struct uart_ops serial_omap_pops = {
1424	.tx_empty	= serial_omap_tx_empty,
1425	.set_mctrl	= serial_omap_set_mctrl,
1426	.get_mctrl	= serial_omap_get_mctrl,
1427	.stop_tx	= serial_omap_stop_tx,
1428	.start_tx	= serial_omap_start_tx,
1429	.throttle	= serial_omap_throttle,
1430	.unthrottle	= serial_omap_unthrottle,
1431	.stop_rx	= serial_omap_stop_rx,
1432	.enable_ms	= serial_omap_enable_ms,
1433	.break_ctl	= serial_omap_break_ctl,
1434	.startup	= serial_omap_startup,
1435	.shutdown	= serial_omap_shutdown,
1436	.set_termios	= serial_omap_set_termios,
1437	.pm		= serial_omap_pm,
1438	.type		= serial_omap_type,
1439	.release_port	= serial_omap_release_port,
1440	.request_port	= serial_omap_request_port,
1441	.config_port	= serial_omap_config_port,
1442	.verify_port	= serial_omap_verify_port,
1443#ifdef CONFIG_CONSOLE_POLL
1444	.poll_put_char  = serial_omap_poll_put_char,
1445	.poll_get_char  = serial_omap_poll_get_char,
1446#endif
1447};
1448
1449static struct uart_driver serial_omap_reg = {
1450	.owner		= THIS_MODULE,
1451	.driver_name	= "OMAP-SERIAL",
1452	.dev_name	= OMAP_SERIAL_NAME,
1453	.nr		= OMAP_MAX_HSUART_PORTS,
1454	.cons		= OMAP_CONSOLE,
1455};
1456
1457#ifdef CONFIG_PM_SLEEP
1458static int serial_omap_prepare(struct device *dev)
1459{
1460	struct uart_omap_port *up = dev_get_drvdata(dev);
1461
1462	up->is_suspending = true;
1463
1464	return 0;
1465}
1466
1467static void serial_omap_complete(struct device *dev)
1468{
1469	struct uart_omap_port *up = dev_get_drvdata(dev);
1470
1471	up->is_suspending = false;
1472}
1473
1474static int serial_omap_suspend(struct device *dev)
1475{
1476	struct uart_omap_port *up = dev_get_drvdata(dev);
1477
1478	uart_suspend_port(&serial_omap_reg, &up->port);
1479	flush_work(&up->qos_work);
1480
1481	if (device_may_wakeup(dev))
1482		serial_omap_enable_wakeup(up, true);
1483	else
1484		serial_omap_enable_wakeup(up, false);
1485
1486	return 0;
1487}
1488
1489static int serial_omap_resume(struct device *dev)
1490{
1491	struct uart_omap_port *up = dev_get_drvdata(dev);
1492
1493	if (device_may_wakeup(dev))
1494		serial_omap_enable_wakeup(up, false);
1495
1496	uart_resume_port(&serial_omap_reg, &up->port);
1497
1498	return 0;
1499}
1500#else
1501#define serial_omap_prepare NULL
1502#define serial_omap_complete NULL
1503#endif /* CONFIG_PM_SLEEP */
1504
1505static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
1506{
1507	u32 mvr, scheme;
1508	u16 revision, major, minor;
1509
1510	mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
1511
1512	/* Check revision register scheme */
1513	scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
1514
1515	switch (scheme) {
1516	case 0: /* Legacy Scheme: OMAP2/3 */
1517		/* MINOR_REV[0:4], MAJOR_REV[4:7] */
1518		major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
1519					OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
1520		minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
1521		break;
1522	case 1:
1523		/* New Scheme: OMAP4+ */
1524		/* MINOR_REV[0:5], MAJOR_REV[8:10] */
1525		major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
1526					OMAP_UART_MVR_MAJ_SHIFT;
1527		minor = (mvr & OMAP_UART_MVR_MIN_MASK);
1528		break;
1529	default:
1530		dev_warn(up->dev,
1531			"Unknown %s revision, defaulting to highest\n",
1532			up->name);
1533		/* highest possible revision */
1534		major = 0xff;
1535		minor = 0xff;
1536	}
1537
1538	/* normalize revision for the driver */
1539	revision = UART_BUILD_REVISION(major, minor);
1540
1541	switch (revision) {
1542	case OMAP_UART_REV_46:
1543		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1544				UART_ERRATA_i291_DMA_FORCEIDLE);
1545		break;
1546	case OMAP_UART_REV_52:
1547		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1548				UART_ERRATA_i291_DMA_FORCEIDLE);
1549		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1550		break;
1551	case OMAP_UART_REV_63:
1552		up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
1553		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1554		break;
1555	default:
1556		break;
1557	}
1558}
1559
1560static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1561{
1562	struct omap_uart_port_info *omap_up_info;
1563
1564	omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1565	if (!omap_up_info)
1566		return NULL; /* out of memory */
1567
1568	of_property_read_u32(dev->of_node, "clock-frequency",
1569					 &omap_up_info->uartclk);
1570	return omap_up_info;
1571}
1572
1573static int serial_omap_probe_rs485(struct uart_omap_port *up,
1574				   struct device_node *np)
1575{
1576	struct serial_rs485 *rs485conf = &up->port.rs485;
1577	u32 rs485_delay[2];
1578	enum of_gpio_flags flags;
1579	int ret;
1580
1581	rs485conf->flags = 0;
1582	up->rts_gpio = -EINVAL;
1583
1584	if (!np)
1585		return 0;
1586
1587	if (of_property_read_bool(np, "rs485-rts-active-high"))
1588		rs485conf->flags |= SER_RS485_RTS_ON_SEND;
1589	else
1590		rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
1591
1592	/* check for tx enable gpio */
1593	up->rts_gpio = of_get_named_gpio_flags(np, "rts-gpio", 0, &flags);
1594	if (gpio_is_valid(up->rts_gpio)) {
1595		ret = devm_gpio_request(up->dev, up->rts_gpio, "omap-serial");
1596		if (ret < 0)
1597			return ret;
1598		ret = gpio_direction_output(up->rts_gpio,
1599					    flags & SER_RS485_RTS_AFTER_SEND);
1600		if (ret < 0)
1601			return ret;
1602	} else if (up->rts_gpio == -EPROBE_DEFER) {
1603		return -EPROBE_DEFER;
1604	} else {
1605		up->rts_gpio = -EINVAL;
1606	}
1607
1608	if (of_property_read_u32_array(np, "rs485-rts-delay",
1609				    rs485_delay, 2) == 0) {
1610		rs485conf->delay_rts_before_send = rs485_delay[0];
1611		rs485conf->delay_rts_after_send = rs485_delay[1];
1612	}
1613
1614	if (of_property_read_bool(np, "rs485-rx-during-tx"))
1615		rs485conf->flags |= SER_RS485_RX_DURING_TX;
1616
1617	if (of_property_read_bool(np, "linux,rs485-enabled-at-boot-time"))
1618		rs485conf->flags |= SER_RS485_ENABLED;
1619
1620	return 0;
1621}
1622
1623static int serial_omap_probe(struct platform_device *pdev)
1624{
1625	struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
1626	struct uart_omap_port *up;
1627	struct resource *mem;
1628	void __iomem *base;
1629	int uartirq = 0;
1630	int wakeirq = 0;
1631	int ret;
1632
1633	/* The optional wakeirq may be specified in the board dts file */
1634	if (pdev->dev.of_node) {
1635		uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0);
1636		if (!uartirq)
1637			return -EPROBE_DEFER;
1638		wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
1639		omap_up_info = of_get_uart_port_info(&pdev->dev);
1640		pdev->dev.platform_data = omap_up_info;
1641	} else {
1642		uartirq = platform_get_irq(pdev, 0);
1643		if (uartirq < 0)
1644			return -EPROBE_DEFER;
1645	}
1646
1647	up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
1648	if (!up)
1649		return -ENOMEM;
1650
1651	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1652	base = devm_ioremap_resource(&pdev->dev, mem);
1653	if (IS_ERR(base))
1654		return PTR_ERR(base);
1655
1656	up->dev = &pdev->dev;
1657	up->port.dev = &pdev->dev;
1658	up->port.type = PORT_OMAP;
1659	up->port.iotype = UPIO_MEM;
1660	up->port.irq = uartirq;
1661	up->port.regshift = 2;
1662	up->port.fifosize = 64;
1663	up->port.ops = &serial_omap_pops;
1664
1665	if (pdev->dev.of_node)
1666		ret = of_alias_get_id(pdev->dev.of_node, "serial");
1667	else
1668		ret = pdev->id;
1669
1670	if (ret < 0) {
1671		dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1672			ret);
1673		goto err_port_line;
1674	}
1675	up->port.line = ret;
1676
1677	if (up->port.line >= OMAP_MAX_HSUART_PORTS) {
1678		dev_err(&pdev->dev, "uart ID %d >  MAX %d.\n", up->port.line,
1679			OMAP_MAX_HSUART_PORTS);
1680		ret = -ENXIO;
1681		goto err_port_line;
1682	}
1683
1684	up->wakeirq = wakeirq;
1685	if (!up->wakeirq)
1686		dev_info(up->port.dev, "no wakeirq for uart%d\n",
1687			 up->port.line);
1688
1689	ret = serial_omap_probe_rs485(up, pdev->dev.of_node);
1690	if (ret < 0)
1691		goto err_rs485;
1692
1693	sprintf(up->name, "OMAP UART%d", up->port.line);
1694	up->port.mapbase = mem->start;
1695	up->port.membase = base;
1696	up->port.flags = omap_up_info->flags;
1697	up->port.uartclk = omap_up_info->uartclk;
1698	up->port.rs485_config = serial_omap_config_rs485;
1699	if (!up->port.uartclk) {
1700		up->port.uartclk = DEFAULT_CLK_SPEED;
1701		dev_warn(&pdev->dev,
1702			 "No clock speed specified: using default: %d\n",
1703			 DEFAULT_CLK_SPEED);
1704	}
1705
1706	up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1707	up->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1708	pm_qos_add_request(&up->pm_qos_request,
1709		PM_QOS_CPU_DMA_LATENCY, up->latency);
1710	INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1711
1712	platform_set_drvdata(pdev, up);
1713	if (omap_up_info->autosuspend_timeout == 0)
1714		omap_up_info->autosuspend_timeout = -1;
1715
1716	device_init_wakeup(up->dev, true);
1717	pm_runtime_use_autosuspend(&pdev->dev);
1718	pm_runtime_set_autosuspend_delay(&pdev->dev,
1719			omap_up_info->autosuspend_timeout);
1720
1721	pm_runtime_irq_safe(&pdev->dev);
1722	pm_runtime_enable(&pdev->dev);
1723
1724	pm_runtime_get_sync(&pdev->dev);
1725
1726	omap_serial_fill_features_erratas(up);
1727
1728	ui[up->port.line] = up;
1729	serial_omap_add_console_port(up);
1730
1731	ret = uart_add_one_port(&serial_omap_reg, &up->port);
1732	if (ret != 0)
1733		goto err_add_port;
1734
1735	pm_runtime_mark_last_busy(up->dev);
1736	pm_runtime_put_autosuspend(up->dev);
1737	return 0;
1738
1739err_add_port:
1740	pm_runtime_put(&pdev->dev);
1741	pm_runtime_disable(&pdev->dev);
1742	pm_qos_remove_request(&up->pm_qos_request);
1743	device_init_wakeup(up->dev, false);
1744err_rs485:
1745err_port_line:
1746	return ret;
1747}
1748
1749static int serial_omap_remove(struct platform_device *dev)
1750{
1751	struct uart_omap_port *up = platform_get_drvdata(dev);
1752
1753	pm_runtime_put_sync(up->dev);
1754	pm_runtime_disable(up->dev);
1755	uart_remove_one_port(&serial_omap_reg, &up->port);
1756	pm_qos_remove_request(&up->pm_qos_request);
1757	device_init_wakeup(&dev->dev, false);
1758
1759	return 0;
1760}
1761
1762/*
1763 * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1764 * The access to uart register after MDR1 Access
1765 * causes UART to corrupt data.
1766 *
1767 * Need a delay =
1768 * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1769 * give 10 times as much
1770 */
1771static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1772{
1773	u8 timeout = 255;
1774
1775	serial_out(up, UART_OMAP_MDR1, mdr1);
1776	udelay(2);
1777	serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1778			UART_FCR_CLEAR_RCVR);
1779	/*
1780	 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1781	 * TX_FIFO_E bit is 1.
1782	 */
1783	while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1784				(UART_LSR_THRE | UART_LSR_DR))) {
1785		timeout--;
1786		if (!timeout) {
1787			/* Should *never* happen. we warn and carry on */
1788			dev_crit(up->dev, "Errata i202: timedout %x\n",
1789						serial_in(up, UART_LSR));
1790			break;
1791		}
1792		udelay(1);
1793	}
1794}
1795
1796#ifdef CONFIG_PM
1797static void serial_omap_restore_context(struct uart_omap_port *up)
1798{
1799	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1800		serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1801	else
1802		serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1803
1804	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1805	serial_out(up, UART_EFR, UART_EFR_ECB);
1806	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1807	serial_out(up, UART_IER, 0x0);
1808	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1809	serial_out(up, UART_DLL, up->dll);
1810	serial_out(up, UART_DLM, up->dlh);
1811	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1812	serial_out(up, UART_IER, up->ier);
1813	serial_out(up, UART_FCR, up->fcr);
1814	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1815	serial_out(up, UART_MCR, up->mcr);
1816	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1817	serial_out(up, UART_OMAP_SCR, up->scr);
1818	serial_out(up, UART_EFR, up->efr);
1819	serial_out(up, UART_LCR, up->lcr);
1820	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1821		serial_omap_mdr1_errataset(up, up->mdr1);
1822	else
1823		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1824	serial_out(up, UART_OMAP_WER, up->wer);
1825}
1826
1827static int serial_omap_runtime_suspend(struct device *dev)
1828{
1829	struct uart_omap_port *up = dev_get_drvdata(dev);
1830
1831	if (!up)
1832		return -EINVAL;
1833
1834	/*
1835	* When using 'no_console_suspend', the console UART must not be
1836	* suspended. Since driver suspend is managed by runtime suspend,
1837	* preventing runtime suspend (by returning error) will keep device
1838	* active during suspend.
1839	*/
1840	if (up->is_suspending && !console_suspend_enabled &&
1841	    uart_console(&up->port))
1842		return -EBUSY;
1843
1844	up->context_loss_cnt = serial_omap_get_context_loss_count(up);
1845
1846	serial_omap_enable_wakeup(up, true);
1847
1848	up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1849	schedule_work(&up->qos_work);
1850
1851	return 0;
1852}
1853
1854static int serial_omap_runtime_resume(struct device *dev)
1855{
1856	struct uart_omap_port *up = dev_get_drvdata(dev);
1857
1858	int loss_cnt = serial_omap_get_context_loss_count(up);
1859
1860	serial_omap_enable_wakeup(up, false);
1861
1862	if (loss_cnt < 0) {
1863		dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
1864			loss_cnt);
1865		serial_omap_restore_context(up);
1866	} else if (up->context_loss_cnt != loss_cnt) {
1867		serial_omap_restore_context(up);
1868	}
1869	up->latency = up->calc_latency;
1870	schedule_work(&up->qos_work);
1871
1872	return 0;
1873}
1874#endif
1875
1876static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1877	SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1878	SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1879				serial_omap_runtime_resume, NULL)
1880	.prepare        = serial_omap_prepare,
1881	.complete       = serial_omap_complete,
1882};
1883
1884#if defined(CONFIG_OF)
1885static const struct of_device_id omap_serial_of_match[] = {
1886	{ .compatible = "ti,omap2-uart" },
1887	{ .compatible = "ti,omap3-uart" },
1888	{ .compatible = "ti,omap4-uart" },
1889	{},
1890};
1891MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1892#endif
1893
1894static struct platform_driver serial_omap_driver = {
1895	.probe          = serial_omap_probe,
1896	.remove         = serial_omap_remove,
1897	.driver		= {
1898		.name	= DRIVER_NAME,
1899		.pm	= &serial_omap_dev_pm_ops,
1900		.of_match_table = of_match_ptr(omap_serial_of_match),
1901	},
1902};
1903
1904static int __init serial_omap_init(void)
1905{
1906	int ret;
1907
1908	ret = uart_register_driver(&serial_omap_reg);
1909	if (ret != 0)
1910		return ret;
1911	ret = platform_driver_register(&serial_omap_driver);
1912	if (ret != 0)
1913		uart_unregister_driver(&serial_omap_reg);
1914	return ret;
1915}
1916
1917static void __exit serial_omap_exit(void)
1918{
1919	platform_driver_unregister(&serial_omap_driver);
1920	uart_unregister_driver(&serial_omap_reg);
1921}
1922
1923module_init(serial_omap_init);
1924module_exit(serial_omap_exit);
1925
1926MODULE_DESCRIPTION("OMAP High Speed UART driver");
1927MODULE_LICENSE("GPL");
1928MODULE_AUTHOR("Texas Instruments Inc");
1929