1/*
2 * 8250-core based driver for the OMAP internal UART
3 *
4 * based on omap-serial.c, Copyright (C) 2010 Texas Instruments.
5 *
6 * Copyright (C) 2014 Sebastian Andrzej Siewior
7 *
8 */
9
10#include <linux/device.h>
11#include <linux/io.h>
12#include <linux/module.h>
13#include <linux/serial_8250.h>
14#include <linux/serial_reg.h>
15#include <linux/tty_flip.h>
16#include <linux/platform_device.h>
17#include <linux/slab.h>
18#include <linux/of.h>
19#include <linux/of_gpio.h>
20#include <linux/of_irq.h>
21#include <linux/delay.h>
22#include <linux/pm_runtime.h>
23#include <linux/console.h>
24#include <linux/pm_qos.h>
25#include <linux/dma-mapping.h>
26
27#include "8250.h"
28
29#define DEFAULT_CLK_SPEED	48000000
30
31#define UART_ERRATA_i202_MDR1_ACCESS	(1 << 0)
32#define OMAP_UART_WER_HAS_TX_WAKEUP	(1 << 1)
33#define OMAP_DMA_TX_KICK		(1 << 2)
34
35#define OMAP_UART_FCR_RX_TRIG		6
36#define OMAP_UART_FCR_TX_TRIG		4
37
38/* SCR register bitmasks */
39#define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK	(1 << 7)
40#define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK	(1 << 6)
41#define OMAP_UART_SCR_TX_EMPTY			(1 << 3)
42#define OMAP_UART_SCR_DMAMODE_MASK		(3 << 1)
43#define OMAP_UART_SCR_DMAMODE_1			(1 << 1)
44#define OMAP_UART_SCR_DMAMODE_CTL		(1 << 0)
45
46/* MVR register bitmasks */
47#define OMAP_UART_MVR_SCHEME_SHIFT	30
48#define OMAP_UART_LEGACY_MVR_MAJ_MASK	0xf0
49#define OMAP_UART_LEGACY_MVR_MAJ_SHIFT	4
50#define OMAP_UART_LEGACY_MVR_MIN_MASK	0x0f
51#define OMAP_UART_MVR_MAJ_MASK		0x700
52#define OMAP_UART_MVR_MAJ_SHIFT		8
53#define OMAP_UART_MVR_MIN_MASK		0x3f
54
55#define UART_TI752_TLR_TX	0
56#define UART_TI752_TLR_RX	4
57
58#define TRIGGER_TLR_MASK(x)	((x & 0x3c) >> 2)
59#define TRIGGER_FCR_MASK(x)	(x & 3)
60
61/* Enable XON/XOFF flow control on output */
62#define OMAP_UART_SW_TX		0x08
63/* Enable XON/XOFF flow control on input */
64#define OMAP_UART_SW_RX		0x02
65
66#define OMAP_UART_WER_MOD_WKUP	0x7f
67#define OMAP_UART_TX_WAKEUP_EN	(1 << 7)
68
69#define TX_TRIGGER	1
70#define RX_TRIGGER	48
71
72#define OMAP_UART_TCR_RESTORE(x)	((x / 4) << 4)
73#define OMAP_UART_TCR_HALT(x)		((x / 4) << 0)
74
75#define UART_BUILD_REVISION(x, y)	(((x) << 8) | (y))
76
77#define OMAP_UART_REV_46 0x0406
78#define OMAP_UART_REV_52 0x0502
79#define OMAP_UART_REV_63 0x0603
80
81struct omap8250_priv {
82	int line;
83	u8 habit;
84	u8 mdr1;
85	u8 efr;
86	u8 scr;
87	u8 wer;
88	u8 xon;
89	u8 xoff;
90	u8 delayed_restore;
91	u16 quot;
92
93	bool is_suspending;
94	int wakeirq;
95	int wakeups_enabled;
96	u32 latency;
97	u32 calc_latency;
98	struct pm_qos_request pm_qos_request;
99	struct work_struct qos_work;
100	struct uart_8250_dma omap8250_dma;
101};
102
103static u32 uart_read(struct uart_8250_port *up, u32 reg)
104{
105	return readl(up->port.membase + (reg << up->port.regshift));
106}
107
108static void omap8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
109{
110	struct uart_8250_port *up = up_to_u8250p(port);
111	struct omap8250_priv *priv = up->port.private_data;
112	u8 lcr;
113
114	serial8250_do_set_mctrl(port, mctrl);
115
116	/*
117	 * Turn off autoRTS if RTS is lowered and restore autoRTS setting
118	 * if RTS is raised
119	 */
120	lcr = serial_in(up, UART_LCR);
121	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
122	if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS))
123		priv->efr |= UART_EFR_RTS;
124	else
125		priv->efr &= ~UART_EFR_RTS;
126	serial_out(up, UART_EFR, priv->efr);
127	serial_out(up, UART_LCR, lcr);
128}
129
130/*
131 * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
132 * The access to uart register after MDR1 Access
133 * causes UART to corrupt data.
134 *
135 * Need a delay =
136 * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
137 * give 10 times as much
138 */
139static void omap_8250_mdr1_errataset(struct uart_8250_port *up,
140				     struct omap8250_priv *priv)
141{
142	u8 timeout = 255;
143	u8 old_mdr1;
144
145	old_mdr1 = serial_in(up, UART_OMAP_MDR1);
146	if (old_mdr1 == priv->mdr1)
147		return;
148
149	serial_out(up, UART_OMAP_MDR1, priv->mdr1);
150	udelay(2);
151	serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
152			UART_FCR_CLEAR_RCVR);
153	/*
154	 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
155	 * TX_FIFO_E bit is 1.
156	 */
157	while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
158				(UART_LSR_THRE | UART_LSR_DR))) {
159		timeout--;
160		if (!timeout) {
161			/* Should *never* happen. we warn and carry on */
162			dev_crit(up->port.dev, "Errata i202: timedout %x\n",
163				 serial_in(up, UART_LSR));
164			break;
165		}
166		udelay(1);
167	}
168}
169
170static void omap_8250_get_divisor(struct uart_port *port, unsigned int baud,
171				  struct omap8250_priv *priv)
172{
173	unsigned int uartclk = port->uartclk;
174	unsigned int div_13, div_16;
175	unsigned int abs_d13, abs_d16;
176
177	/*
178	 * Old custom speed handling.
179	 */
180	if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST) {
181		priv->quot = port->custom_divisor & 0xffff;
182		/*
183		 * I assume that nobody is using this. But hey, if somebody
184		 * would like to specify the divisor _and_ the mode then the
185		 * driver is ready and waiting for it.
186		 */
187		if (port->custom_divisor & (1 << 16))
188			priv->mdr1 = UART_OMAP_MDR1_13X_MODE;
189		else
190			priv->mdr1 = UART_OMAP_MDR1_16X_MODE;
191		return;
192	}
193	div_13 = DIV_ROUND_CLOSEST(uartclk, 13 * baud);
194	div_16 = DIV_ROUND_CLOSEST(uartclk, 16 * baud);
195
196	if (!div_13)
197		div_13 = 1;
198	if (!div_16)
199		div_16 = 1;
200
201	abs_d13 = abs(baud - uartclk / 13 / div_13);
202	abs_d16 = abs(baud - uartclk / 16 / div_16);
203
204	if (abs_d13 >= abs_d16) {
205		priv->mdr1 = UART_OMAP_MDR1_16X_MODE;
206		priv->quot = div_16;
207	} else {
208		priv->mdr1 = UART_OMAP_MDR1_13X_MODE;
209		priv->quot = div_13;
210	}
211}
212
213static void omap8250_update_scr(struct uart_8250_port *up,
214				struct omap8250_priv *priv)
215{
216	u8 old_scr;
217
218	old_scr = serial_in(up, UART_OMAP_SCR);
219	if (old_scr == priv->scr)
220		return;
221
222	/*
223	 * The manual recommends not to enable the DMA mode selector in the SCR
224	 * (instead of the FCR) register _and_ selecting the DMA mode as one
225	 * register write because this may lead to malfunction.
226	 */
227	if (priv->scr & OMAP_UART_SCR_DMAMODE_MASK)
228		serial_out(up, UART_OMAP_SCR,
229			   priv->scr & ~OMAP_UART_SCR_DMAMODE_MASK);
230	serial_out(up, UART_OMAP_SCR, priv->scr);
231}
232
233static void omap8250_restore_regs(struct uart_8250_port *up)
234{
235	struct omap8250_priv *priv = up->port.private_data;
236	struct uart_8250_dma	*dma = up->dma;
237
238	if (dma && dma->tx_running) {
239		/*
240		 * TCSANOW requests the change to occur immediately however if
241		 * we have a TX-DMA operation in progress then it has been
242		 * observed that it might stall and never complete. Therefore we
243		 * delay DMA completes to prevent this hang from happen.
244		 */
245		priv->delayed_restore = 1;
246		return;
247	}
248
249	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
250	serial_out(up, UART_EFR, UART_EFR_ECB);
251
252	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
253	serial_out(up, UART_MCR, UART_MCR_TCRTLR);
254	serial_out(up, UART_FCR, up->fcr);
255
256	omap8250_update_scr(up, priv);
257
258	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
259
260	serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_RESTORE(16) |
261			OMAP_UART_TCR_HALT(52));
262	serial_out(up, UART_TI752_TLR,
263		   TRIGGER_TLR_MASK(TX_TRIGGER) << UART_TI752_TLR_TX |
264		   TRIGGER_TLR_MASK(RX_TRIGGER) << UART_TI752_TLR_RX);
265
266	serial_out(up, UART_LCR, 0);
267
268	/* drop TCR + TLR access, we setup XON/XOFF later */
269	serial_out(up, UART_MCR, up->mcr);
270	serial_out(up, UART_IER, up->ier);
271
272	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
273	serial_dl_write(up, priv->quot);
274
275	serial_out(up, UART_EFR, priv->efr);
276
277	/* Configure flow control */
278	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
279	serial_out(up, UART_XON1, priv->xon);
280	serial_out(up, UART_XOFF1, priv->xoff);
281
282	serial_out(up, UART_LCR, up->lcr);
283	/* need mode A for FCR */
284	if (priv->habit & UART_ERRATA_i202_MDR1_ACCESS)
285		omap_8250_mdr1_errataset(up, priv);
286	else
287		serial_out(up, UART_OMAP_MDR1, priv->mdr1);
288	up->port.ops->set_mctrl(&up->port, up->port.mctrl);
289}
290
291/*
292 * OMAP can use "CLK / (16 or 13) / div" for baud rate. And then we have have
293 * some differences in how we want to handle flow control.
294 */
295static void omap_8250_set_termios(struct uart_port *port,
296				  struct ktermios *termios,
297				  struct ktermios *old)
298{
299	struct uart_8250_port *up =
300		container_of(port, struct uart_8250_port, port);
301	struct omap8250_priv *priv = up->port.private_data;
302	unsigned char cval = 0;
303	unsigned int baud;
304
305	switch (termios->c_cflag & CSIZE) {
306	case CS5:
307		cval = UART_LCR_WLEN5;
308		break;
309	case CS6:
310		cval = UART_LCR_WLEN6;
311		break;
312	case CS7:
313		cval = UART_LCR_WLEN7;
314		break;
315	default:
316	case CS8:
317		cval = UART_LCR_WLEN8;
318		break;
319	}
320
321	if (termios->c_cflag & CSTOPB)
322		cval |= UART_LCR_STOP;
323	if (termios->c_cflag & PARENB)
324		cval |= UART_LCR_PARITY;
325	if (!(termios->c_cflag & PARODD))
326		cval |= UART_LCR_EPAR;
327	if (termios->c_cflag & CMSPAR)
328		cval |= UART_LCR_SPAR;
329
330	/*
331	 * Ask the core to calculate the divisor for us.
332	 */
333	baud = uart_get_baud_rate(port, termios, old,
334				  port->uartclk / 16 / 0xffff,
335				  port->uartclk / 13);
336	omap_8250_get_divisor(port, baud, priv);
337
338	/*
339	 * Ok, we're now changing the port state. Do it with
340	 * interrupts disabled.
341	 */
342	pm_runtime_get_sync(port->dev);
343	spin_lock_irq(&port->lock);
344
345	/*
346	 * Update the per-port timeout.
347	 */
348	uart_update_timeout(port, termios->c_cflag, baud);
349
350	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
351	if (termios->c_iflag & INPCK)
352		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
353	if (termios->c_iflag & (IGNBRK | PARMRK))
354		up->port.read_status_mask |= UART_LSR_BI;
355
356	/*
357	 * Characters to ignore
358	 */
359	up->port.ignore_status_mask = 0;
360	if (termios->c_iflag & IGNPAR)
361		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
362	if (termios->c_iflag & IGNBRK) {
363		up->port.ignore_status_mask |= UART_LSR_BI;
364		/*
365		 * If we're ignoring parity and break indicators,
366		 * ignore overruns too (for real raw support).
367		 */
368		if (termios->c_iflag & IGNPAR)
369			up->port.ignore_status_mask |= UART_LSR_OE;
370	}
371
372	/*
373	 * ignore all characters if CREAD is not set
374	 */
375	if ((termios->c_cflag & CREAD) == 0)
376		up->port.ignore_status_mask |= UART_LSR_DR;
377
378	/*
379	 * Modem status interrupts
380	 */
381	up->ier &= ~UART_IER_MSI;
382	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
383		up->ier |= UART_IER_MSI;
384
385	up->lcr = cval;
386	/* Up to here it was mostly serial8250_do_set_termios() */
387
388	/*
389	 * We enable TRIG_GRANU for RX and TX and additionaly we set
390	 * SCR_TX_EMPTY bit. The result is the following:
391	 * - RX_TRIGGER amount of bytes in the FIFO will cause an interrupt.
392	 * - less than RX_TRIGGER number of bytes will also cause an interrupt
393	 *   once the UART decides that there no new bytes arriving.
394	 * - Once THRE is enabled, the interrupt will be fired once the FIFO is
395	 *   empty - the trigger level is ignored here.
396	 *
397	 * Once DMA is enabled:
398	 * - UART will assert the TX DMA line once there is room for TX_TRIGGER
399	 *   bytes in the TX FIFO. On each assert the DMA engine will move
400	 *   TX_TRIGGER bytes into the FIFO.
401	 * - UART will assert the RX DMA line once there are RX_TRIGGER bytes in
402	 *   the FIFO and move RX_TRIGGER bytes.
403	 * This is because threshold and trigger values are the same.
404	 */
405	up->fcr = UART_FCR_ENABLE_FIFO;
406	up->fcr |= TRIGGER_FCR_MASK(TX_TRIGGER) << OMAP_UART_FCR_TX_TRIG;
407	up->fcr |= TRIGGER_FCR_MASK(RX_TRIGGER) << OMAP_UART_FCR_RX_TRIG;
408
409	priv->scr = OMAP_UART_SCR_RX_TRIG_GRANU1_MASK | OMAP_UART_SCR_TX_EMPTY |
410		OMAP_UART_SCR_TX_TRIG_GRANU1_MASK;
411
412	if (up->dma)
413		priv->scr |= OMAP_UART_SCR_DMAMODE_1 |
414			OMAP_UART_SCR_DMAMODE_CTL;
415
416	priv->xon = termios->c_cc[VSTART];
417	priv->xoff = termios->c_cc[VSTOP];
418
419	priv->efr = 0;
420	up->mcr &= ~(UART_MCR_RTS | UART_MCR_XONANY);
421	up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
422
423	if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
424		/* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */
425		up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
426		priv->efr |= UART_EFR_CTS;
427	} else	if (up->port.flags & UPF_SOFT_FLOW) {
428		/*
429		 * IXON Flag:
430		 * Enable XON/XOFF flow control on input.
431		 * Receiver compares XON1, XOFF1.
432		 */
433		if (termios->c_iflag & IXON)
434			priv->efr |= OMAP_UART_SW_RX;
435
436		/*
437		 * IXOFF Flag:
438		 * Enable XON/XOFF flow control on output.
439		 * Transmit XON1, XOFF1
440		 */
441		if (termios->c_iflag & IXOFF) {
442			up->port.status |= UPSTAT_AUTOXOFF;
443			priv->efr |= OMAP_UART_SW_TX;
444		}
445
446		/*
447		 * IXANY Flag:
448		 * Enable any character to restart output.
449		 * Operation resumes after receiving any
450		 * character after recognition of the XOFF character
451		 */
452		if (termios->c_iflag & IXANY)
453			up->mcr |= UART_MCR_XONANY;
454	}
455	omap8250_restore_regs(up);
456
457	spin_unlock_irq(&up->port.lock);
458	pm_runtime_mark_last_busy(port->dev);
459	pm_runtime_put_autosuspend(port->dev);
460
461	/* calculate wakeup latency constraint */
462	priv->calc_latency = USEC_PER_SEC * 64 * 8 / baud;
463	priv->latency = priv->calc_latency;
464
465	schedule_work(&priv->qos_work);
466
467	/* Don't rewrite B0 */
468	if (tty_termios_baud_rate(termios))
469		tty_termios_encode_baud_rate(termios, baud, baud);
470}
471
472/* same as 8250 except that we may have extra flow bits set in EFR */
473static void omap_8250_pm(struct uart_port *port, unsigned int state,
474			 unsigned int oldstate)
475{
476	struct uart_8250_port *up = up_to_u8250p(port);
477	u8 efr;
478
479	pm_runtime_get_sync(port->dev);
480	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
481	efr = serial_in(up, UART_EFR);
482	serial_out(up, UART_EFR, efr | UART_EFR_ECB);
483	serial_out(up, UART_LCR, 0);
484
485	serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
486	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
487	serial_out(up, UART_EFR, efr);
488	serial_out(up, UART_LCR, 0);
489
490	pm_runtime_mark_last_busy(port->dev);
491	pm_runtime_put_autosuspend(port->dev);
492}
493
494static void omap_serial_fill_features_erratas(struct uart_8250_port *up,
495					      struct omap8250_priv *priv)
496{
497	u32 mvr, scheme;
498	u16 revision, major, minor;
499
500	mvr = uart_read(up, UART_OMAP_MVER);
501
502	/* Check revision register scheme */
503	scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
504
505	switch (scheme) {
506	case 0: /* Legacy Scheme: OMAP2/3 */
507		/* MINOR_REV[0:4], MAJOR_REV[4:7] */
508		major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
509			OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
510		minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
511		break;
512	case 1:
513		/* New Scheme: OMAP4+ */
514		/* MINOR_REV[0:5], MAJOR_REV[8:10] */
515		major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
516			OMAP_UART_MVR_MAJ_SHIFT;
517		minor = (mvr & OMAP_UART_MVR_MIN_MASK);
518		break;
519	default:
520		dev_warn(up->port.dev,
521			 "Unknown revision, defaulting to highest\n");
522		/* highest possible revision */
523		major = 0xff;
524		minor = 0xff;
525	}
526	/* normalize revision for the driver */
527	revision = UART_BUILD_REVISION(major, minor);
528
529	switch (revision) {
530	case OMAP_UART_REV_46:
531		priv->habit = UART_ERRATA_i202_MDR1_ACCESS;
532		break;
533	case OMAP_UART_REV_52:
534		priv->habit = UART_ERRATA_i202_MDR1_ACCESS |
535				OMAP_UART_WER_HAS_TX_WAKEUP;
536		break;
537	case OMAP_UART_REV_63:
538		priv->habit = UART_ERRATA_i202_MDR1_ACCESS |
539			OMAP_UART_WER_HAS_TX_WAKEUP;
540		break;
541	default:
542		break;
543	}
544}
545
546static void omap8250_uart_qos_work(struct work_struct *work)
547{
548	struct omap8250_priv *priv;
549
550	priv = container_of(work, struct omap8250_priv, qos_work);
551	pm_qos_update_request(&priv->pm_qos_request, priv->latency);
552}
553
554static irqreturn_t omap_wake_irq(int irq, void *dev_id)
555{
556	struct uart_port *port = dev_id;
557	int ret;
558
559	ret = port->handle_irq(port);
560	if (ret)
561		return IRQ_HANDLED;
562	return IRQ_NONE;
563}
564
565#ifdef CONFIG_SERIAL_8250_DMA
566static int omap_8250_dma_handle_irq(struct uart_port *port);
567#endif
568
569static irqreturn_t omap8250_irq(int irq, void *dev_id)
570{
571	struct uart_port *port = dev_id;
572	struct uart_8250_port *up = up_to_u8250p(port);
573	unsigned int iir;
574	int ret;
575
576#ifdef CONFIG_SERIAL_8250_DMA
577	if (up->dma) {
578		ret = omap_8250_dma_handle_irq(port);
579		return IRQ_RETVAL(ret);
580	}
581#endif
582
583	serial8250_rpm_get(up);
584	iir = serial_port_in(port, UART_IIR);
585	ret = serial8250_handle_irq(port, iir);
586	serial8250_rpm_put(up);
587
588	return IRQ_RETVAL(ret);
589}
590
591static int omap_8250_startup(struct uart_port *port)
592{
593	struct uart_8250_port *up = up_to_u8250p(port);
594	struct omap8250_priv *priv = port->private_data;
595	int ret;
596
597	if (priv->wakeirq) {
598		ret = request_irq(priv->wakeirq, omap_wake_irq,
599				  port->irqflags, "uart wakeup irq", port);
600		if (ret)
601			return ret;
602		disable_irq(priv->wakeirq);
603	}
604
605	pm_runtime_get_sync(port->dev);
606
607	up->mcr = 0;
608	serial_out(up, UART_FCR, UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
609
610	serial_out(up, UART_LCR, UART_LCR_WLEN8);
611
612	up->lsr_saved_flags = 0;
613	up->msr_saved_flags = 0;
614
615	if (up->dma) {
616		ret = serial8250_request_dma(up);
617		if (ret) {
618			dev_warn_ratelimited(port->dev,
619					     "failed to request DMA\n");
620			up->dma = NULL;
621		}
622	}
623
624	ret = request_irq(port->irq, omap8250_irq, IRQF_SHARED,
625			  dev_name(port->dev), port);
626	if (ret < 0)
627		goto err;
628
629	up->ier = UART_IER_RLSI | UART_IER_RDI;
630	serial_out(up, UART_IER, up->ier);
631
632#ifdef CONFIG_PM
633	up->capabilities |= UART_CAP_RPM;
634#endif
635
636	/* Enable module level wake up */
637	priv->wer = OMAP_UART_WER_MOD_WKUP;
638	if (priv->habit & OMAP_UART_WER_HAS_TX_WAKEUP)
639		priv->wer |= OMAP_UART_TX_WAKEUP_EN;
640	serial_out(up, UART_OMAP_WER, priv->wer);
641
642	if (up->dma)
643		up->dma->rx_dma(up, 0);
644
645	pm_runtime_mark_last_busy(port->dev);
646	pm_runtime_put_autosuspend(port->dev);
647	return 0;
648err:
649	pm_runtime_mark_last_busy(port->dev);
650	pm_runtime_put_autosuspend(port->dev);
651	if (priv->wakeirq)
652		free_irq(priv->wakeirq, port);
653	return ret;
654}
655
656static void omap_8250_shutdown(struct uart_port *port)
657{
658	struct uart_8250_port *up = up_to_u8250p(port);
659	struct omap8250_priv *priv = port->private_data;
660
661	flush_work(&priv->qos_work);
662	if (up->dma)
663		up->dma->rx_dma(up, UART_IIR_RX_TIMEOUT);
664
665	pm_runtime_get_sync(port->dev);
666
667	serial_out(up, UART_OMAP_WER, 0);
668
669	up->ier = 0;
670	serial_out(up, UART_IER, 0);
671
672	if (up->dma)
673		serial8250_release_dma(up);
674
675	/*
676	 * Disable break condition and FIFOs
677	 */
678	if (up->lcr & UART_LCR_SBC)
679		serial_out(up, UART_LCR, up->lcr & ~UART_LCR_SBC);
680	serial_out(up, UART_FCR, UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
681
682	pm_runtime_mark_last_busy(port->dev);
683	pm_runtime_put_autosuspend(port->dev);
684
685	free_irq(port->irq, port);
686	if (priv->wakeirq)
687		free_irq(priv->wakeirq, port);
688}
689
690static void omap_8250_throttle(struct uart_port *port)
691{
692	unsigned long flags;
693	struct uart_8250_port *up =
694		container_of(port, struct uart_8250_port, port);
695
696	pm_runtime_get_sync(port->dev);
697
698	spin_lock_irqsave(&port->lock, flags);
699	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
700	serial_out(up, UART_IER, up->ier);
701	spin_unlock_irqrestore(&port->lock, flags);
702
703	pm_runtime_mark_last_busy(port->dev);
704	pm_runtime_put_autosuspend(port->dev);
705}
706
707static void omap_8250_unthrottle(struct uart_port *port)
708{
709	unsigned long flags;
710	struct uart_8250_port *up =
711		container_of(port, struct uart_8250_port, port);
712
713	pm_runtime_get_sync(port->dev);
714
715	spin_lock_irqsave(&port->lock, flags);
716	up->ier |= UART_IER_RLSI | UART_IER_RDI;
717	serial_out(up, UART_IER, up->ier);
718	spin_unlock_irqrestore(&port->lock, flags);
719
720	pm_runtime_mark_last_busy(port->dev);
721	pm_runtime_put_autosuspend(port->dev);
722}
723
724#ifdef CONFIG_SERIAL_8250_DMA
725static int omap_8250_rx_dma(struct uart_8250_port *p, unsigned int iir);
726
727static void __dma_rx_do_complete(struct uart_8250_port *p, bool error)
728{
729	struct uart_8250_dma    *dma = p->dma;
730	struct tty_port         *tty_port = &p->port.state->port;
731	struct dma_tx_state     state;
732	int                     count;
733
734	dma_sync_single_for_cpu(dma->rxchan->device->dev, dma->rx_addr,
735				dma->rx_size, DMA_FROM_DEVICE);
736
737	dma->rx_running = 0;
738	dmaengine_tx_status(dma->rxchan, dma->rx_cookie, &state);
739	dmaengine_terminate_all(dma->rxchan);
740
741	count = dma->rx_size - state.residue;
742
743	tty_insert_flip_string(tty_port, dma->rx_buf, count);
744	p->port.icount.rx += count;
745	if (!error)
746		omap_8250_rx_dma(p, 0);
747
748	tty_flip_buffer_push(tty_port);
749}
750
751static void __dma_rx_complete(void *param)
752{
753	__dma_rx_do_complete(param, false);
754}
755
756static int omap_8250_rx_dma(struct uart_8250_port *p, unsigned int iir)
757{
758	struct uart_8250_dma            *dma = p->dma;
759	struct dma_async_tx_descriptor  *desc;
760
761	switch (iir & 0x3f) {
762	case UART_IIR_RLSI:
763		/* 8250_core handles errors and break interrupts */
764		if (dma->rx_running) {
765			dmaengine_pause(dma->rxchan);
766			__dma_rx_do_complete(p, true);
767		}
768		return -EIO;
769	case UART_IIR_RX_TIMEOUT:
770		/*
771		 * If RCVR FIFO trigger level was not reached, complete the
772		 * transfer and let 8250_core copy the remaining data.
773		 */
774		if (dma->rx_running) {
775			dmaengine_pause(dma->rxchan);
776			__dma_rx_do_complete(p, true);
777		}
778		return -ETIMEDOUT;
779	case UART_IIR_RDI:
780		/*
781		 * The OMAP UART is a special BEAST. If we receive RDI we _have_
782		 * a DMA transfer programmed but it didn't work. One reason is
783		 * that we were too slow and there were too many bytes in the
784		 * FIFO, the UART counted wrong and never kicked the DMA engine
785		 * to do anything. That means once we receive RDI on OMAP then
786		 * the DMA won't do anything soon so we have to cancel the DMA
787		 * transfer and purge the FIFO manually.
788		 */
789		if (dma->rx_running) {
790			dmaengine_pause(dma->rxchan);
791			__dma_rx_do_complete(p, true);
792		}
793		return -ETIMEDOUT;
794
795	default:
796		break;
797	}
798
799	if (dma->rx_running)
800		return 0;
801
802	desc = dmaengine_prep_slave_single(dma->rxchan, dma->rx_addr,
803					   dma->rx_size, DMA_DEV_TO_MEM,
804					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
805	if (!desc)
806		return -EBUSY;
807
808	dma->rx_running = 1;
809	desc->callback = __dma_rx_complete;
810	desc->callback_param = p;
811
812	dma->rx_cookie = dmaengine_submit(desc);
813
814	dma_sync_single_for_device(dma->rxchan->device->dev, dma->rx_addr,
815				   dma->rx_size, DMA_FROM_DEVICE);
816
817	dma_async_issue_pending(dma->rxchan);
818	return 0;
819}
820
821static int omap_8250_tx_dma(struct uart_8250_port *p);
822
823static void omap_8250_dma_tx_complete(void *param)
824{
825	struct uart_8250_port	*p = param;
826	struct uart_8250_dma	*dma = p->dma;
827	struct circ_buf		*xmit = &p->port.state->xmit;
828	unsigned long		flags;
829	bool			en_thri = false;
830	struct omap8250_priv	*priv = p->port.private_data;
831
832	dma_sync_single_for_cpu(dma->txchan->device->dev, dma->tx_addr,
833				UART_XMIT_SIZE, DMA_TO_DEVICE);
834
835	spin_lock_irqsave(&p->port.lock, flags);
836
837	dma->tx_running = 0;
838
839	xmit->tail += dma->tx_size;
840	xmit->tail &= UART_XMIT_SIZE - 1;
841	p->port.icount.tx += dma->tx_size;
842
843	if (priv->delayed_restore) {
844		priv->delayed_restore = 0;
845		omap8250_restore_regs(p);
846	}
847
848	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
849		uart_write_wakeup(&p->port);
850
851	if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) {
852		int ret;
853
854		ret = omap_8250_tx_dma(p);
855		if (ret)
856			en_thri = true;
857
858	} else if (p->capabilities & UART_CAP_RPM) {
859		en_thri = true;
860	}
861
862	if (en_thri) {
863		dma->tx_err = 1;
864		p->ier |= UART_IER_THRI;
865		serial_port_out(&p->port, UART_IER, p->ier);
866	}
867
868	spin_unlock_irqrestore(&p->port.lock, flags);
869}
870
871static int omap_8250_tx_dma(struct uart_8250_port *p)
872{
873	struct uart_8250_dma		*dma = p->dma;
874	struct omap8250_priv		*priv = p->port.private_data;
875	struct circ_buf			*xmit = &p->port.state->xmit;
876	struct dma_async_tx_descriptor	*desc;
877	unsigned int	skip_byte = 0;
878	int ret;
879
880	if (dma->tx_running)
881		return 0;
882	if (uart_tx_stopped(&p->port) || uart_circ_empty(xmit)) {
883
884		/*
885		 * Even if no data, we need to return an error for the two cases
886		 * below so serial8250_tx_chars() is invoked and properly clears
887		 * THRI and/or runtime suspend.
888		 */
889		if (dma->tx_err || p->capabilities & UART_CAP_RPM) {
890			ret = -EBUSY;
891			goto err;
892		}
893		if (p->ier & UART_IER_THRI) {
894			p->ier &= ~UART_IER_THRI;
895			serial_out(p, UART_IER, p->ier);
896		}
897		return 0;
898	}
899
900	dma->tx_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
901	if (priv->habit & OMAP_DMA_TX_KICK) {
902		u8 tx_lvl;
903
904		/*
905		 * We need to put the first byte into the FIFO in order to start
906		 * the DMA transfer. For transfers smaller than four bytes we
907		 * don't bother doing DMA at all. It seem not matter if there
908		 * are still bytes in the FIFO from the last transfer (in case
909		 * we got here directly from omap_8250_dma_tx_complete()). Bytes
910		 * leaving the FIFO seem not to trigger the DMA transfer. It is
911		 * really the byte that we put into the FIFO.
912		 * If the FIFO is already full then we most likely got here from
913		 * omap_8250_dma_tx_complete(). And this means the DMA engine
914		 * just completed its work. We don't have to wait the complete
915		 * 86us at 115200,8n1 but around 60us (not to mention lower
916		 * baudrates). So in that case we take the interrupt and try
917		 * again with an empty FIFO.
918		 */
919		tx_lvl = serial_in(p, UART_OMAP_TX_LVL);
920		if (tx_lvl == p->tx_loadsz) {
921			ret = -EBUSY;
922			goto err;
923		}
924		if (dma->tx_size < 4) {
925			ret = -EINVAL;
926			goto err;
927		}
928		skip_byte = 1;
929	}
930
931	desc = dmaengine_prep_slave_single(dma->txchan,
932			dma->tx_addr + xmit->tail + skip_byte,
933			dma->tx_size - skip_byte, DMA_MEM_TO_DEV,
934			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
935	if (!desc) {
936		ret = -EBUSY;
937		goto err;
938	}
939
940	dma->tx_running = 1;
941
942	desc->callback = omap_8250_dma_tx_complete;
943	desc->callback_param = p;
944
945	dma->tx_cookie = dmaengine_submit(desc);
946
947	dma_sync_single_for_device(dma->txchan->device->dev, dma->tx_addr,
948				   UART_XMIT_SIZE, DMA_TO_DEVICE);
949
950	dma_async_issue_pending(dma->txchan);
951	if (dma->tx_err)
952		dma->tx_err = 0;
953
954	if (p->ier & UART_IER_THRI) {
955		p->ier &= ~UART_IER_THRI;
956		serial_out(p, UART_IER, p->ier);
957	}
958	if (skip_byte)
959		serial_out(p, UART_TX, xmit->buf[xmit->tail]);
960	return 0;
961err:
962	dma->tx_err = 1;
963	return ret;
964}
965
966/*
967 * This is mostly serial8250_handle_irq(). We have a slightly different DMA
968 * hoook for RX/TX and need different logic for them in the ISR. Therefore we
969 * use the default routine in the non-DMA case and this one for with DMA.
970 */
971static int omap_8250_dma_handle_irq(struct uart_port *port)
972{
973	struct uart_8250_port *up = up_to_u8250p(port);
974	unsigned char status;
975	unsigned long flags;
976	u8 iir;
977	int dma_err = 0;
978
979	serial8250_rpm_get(up);
980
981	iir = serial_port_in(port, UART_IIR);
982	if (iir & UART_IIR_NO_INT) {
983		serial8250_rpm_put(up);
984		return 0;
985	}
986
987	spin_lock_irqsave(&port->lock, flags);
988
989	status = serial_port_in(port, UART_LSR);
990
991	if (status & (UART_LSR_DR | UART_LSR_BI)) {
992
993		dma_err = omap_8250_rx_dma(up, iir);
994		if (dma_err) {
995			status = serial8250_rx_chars(up, status);
996			omap_8250_rx_dma(up, 0);
997		}
998	}
999	serial8250_modem_status(up);
1000	if (status & UART_LSR_THRE && up->dma->tx_err) {
1001		if (uart_tx_stopped(&up->port) ||
1002		    uart_circ_empty(&up->port.state->xmit)) {
1003			up->dma->tx_err = 0;
1004			serial8250_tx_chars(up);
1005		} else  {
1006			/*
1007			 * try again due to an earlier failer which
1008			 * might have been resolved by now.
1009			 */
1010			dma_err = omap_8250_tx_dma(up);
1011			if (dma_err)
1012				serial8250_tx_chars(up);
1013		}
1014	}
1015
1016	spin_unlock_irqrestore(&port->lock, flags);
1017	serial8250_rpm_put(up);
1018	return 1;
1019}
1020
1021static bool the_no_dma_filter_fn(struct dma_chan *chan, void *param)
1022{
1023	return false;
1024}
1025
1026#else
1027
1028static inline int omap_8250_rx_dma(struct uart_8250_port *p, unsigned int iir)
1029{
1030	return -EINVAL;
1031}
1032#endif
1033
1034static int omap8250_no_handle_irq(struct uart_port *port)
1035{
1036	/* IRQ has not been requested but handling irq? */
1037	WARN_ONCE(1, "Unexpected irq handling before port startup\n");
1038	return 0;
1039}
1040
1041static int omap8250_probe(struct platform_device *pdev)
1042{
1043	struct resource *regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1044	struct resource *irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1045	struct omap8250_priv *priv;
1046	struct uart_8250_port up;
1047	int ret;
1048	void __iomem *membase;
1049
1050	if (!regs || !irq) {
1051		dev_err(&pdev->dev, "missing registers or irq\n");
1052		return -EINVAL;
1053	}
1054
1055	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
1056	if (!priv)
1057		return -ENOMEM;
1058
1059	membase = devm_ioremap_nocache(&pdev->dev, regs->start,
1060				       resource_size(regs));
1061	if (!membase)
1062		return -ENODEV;
1063
1064	memset(&up, 0, sizeof(up));
1065	up.port.dev = &pdev->dev;
1066	up.port.mapbase = regs->start;
1067	up.port.membase = membase;
1068	up.port.irq = irq->start;
1069	/*
1070	 * It claims to be 16C750 compatible however it is a little different.
1071	 * It has EFR and has no FCR7_64byte bit. The AFE (which it claims to
1072	 * have) is enabled via EFR instead of MCR. The type is set here 8250
1073	 * just to get things going. UNKNOWN does not work for a few reasons and
1074	 * we don't need our own type since we don't use 8250's set_termios()
1075	 * or pm callback.
1076	 */
1077	up.port.type = PORT_8250;
1078	up.port.iotype = UPIO_MEM;
1079	up.port.flags = UPF_FIXED_PORT | UPF_FIXED_TYPE | UPF_SOFT_FLOW |
1080		UPF_HARD_FLOW;
1081	up.port.private_data = priv;
1082
1083	up.port.regshift = 2;
1084	up.port.fifosize = 64;
1085	up.tx_loadsz = 64;
1086	up.capabilities = UART_CAP_FIFO;
1087#ifdef CONFIG_PM
1088	/*
1089	 * Runtime PM is mostly transparent. However to do it right we need to a
1090	 * TX empty interrupt before we can put the device to auto idle. So if
1091	 * PM is not enabled we don't add that flag and can spare that one extra
1092	 * interrupt in the TX path.
1093	 */
1094	up.capabilities |= UART_CAP_RPM;
1095#endif
1096	up.port.set_termios = omap_8250_set_termios;
1097	up.port.set_mctrl = omap8250_set_mctrl;
1098	up.port.pm = omap_8250_pm;
1099	up.port.startup = omap_8250_startup;
1100	up.port.shutdown = omap_8250_shutdown;
1101	up.port.throttle = omap_8250_throttle;
1102	up.port.unthrottle = omap_8250_unthrottle;
1103
1104	if (pdev->dev.of_node) {
1105		ret = of_alias_get_id(pdev->dev.of_node, "serial");
1106
1107		of_property_read_u32(pdev->dev.of_node, "clock-frequency",
1108				     &up.port.uartclk);
1109		priv->wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
1110	} else {
1111		ret = pdev->id;
1112	}
1113	if (ret < 0) {
1114		dev_err(&pdev->dev, "failed to get alias/pdev id\n");
1115		return ret;
1116	}
1117	up.port.line = ret;
1118
1119	if (!up.port.uartclk) {
1120		up.port.uartclk = DEFAULT_CLK_SPEED;
1121		dev_warn(&pdev->dev,
1122			 "No clock speed specified: using default: %d\n",
1123			 DEFAULT_CLK_SPEED);
1124	}
1125
1126	priv->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1127	priv->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1128	pm_qos_add_request(&priv->pm_qos_request, PM_QOS_CPU_DMA_LATENCY,
1129			   priv->latency);
1130	INIT_WORK(&priv->qos_work, omap8250_uart_qos_work);
1131
1132	device_init_wakeup(&pdev->dev, true);
1133	pm_runtime_use_autosuspend(&pdev->dev);
1134	pm_runtime_set_autosuspend_delay(&pdev->dev, -1);
1135
1136	pm_runtime_irq_safe(&pdev->dev);
1137	pm_runtime_enable(&pdev->dev);
1138
1139	pm_runtime_get_sync(&pdev->dev);
1140
1141	omap_serial_fill_features_erratas(&up, priv);
1142	up.port.handle_irq = omap8250_no_handle_irq;
1143#ifdef CONFIG_SERIAL_8250_DMA
1144	if (pdev->dev.of_node) {
1145		/*
1146		 * Oh DMA support. If there are no DMA properties in the DT then
1147		 * we will fall back to a generic DMA channel which does not
1148		 * really work here. To ensure that we do not get a generic DMA
1149		 * channel assigned, we have the the_no_dma_filter_fn() here.
1150		 * To avoid "failed to request DMA" messages we check for DMA
1151		 * properties in DT.
1152		 */
1153		ret = of_property_count_strings(pdev->dev.of_node, "dma-names");
1154		if (ret == 2) {
1155			up.dma = &priv->omap8250_dma;
1156			priv->omap8250_dma.fn = the_no_dma_filter_fn;
1157			priv->omap8250_dma.tx_dma = omap_8250_tx_dma;
1158			priv->omap8250_dma.rx_dma = omap_8250_rx_dma;
1159			priv->omap8250_dma.rx_size = RX_TRIGGER;
1160			priv->omap8250_dma.rxconf.src_maxburst = RX_TRIGGER;
1161			priv->omap8250_dma.txconf.dst_maxburst = TX_TRIGGER;
1162
1163			if (of_machine_is_compatible("ti,am33xx"))
1164				priv->habit |= OMAP_DMA_TX_KICK;
1165		}
1166	}
1167#endif
1168	ret = serial8250_register_8250_port(&up);
1169	if (ret < 0) {
1170		dev_err(&pdev->dev, "unable to register 8250 port\n");
1171		goto err;
1172	}
1173	priv->line = ret;
1174	platform_set_drvdata(pdev, priv);
1175	pm_runtime_mark_last_busy(&pdev->dev);
1176	pm_runtime_put_autosuspend(&pdev->dev);
1177	return 0;
1178err:
1179	pm_runtime_put(&pdev->dev);
1180	pm_runtime_disable(&pdev->dev);
1181	return ret;
1182}
1183
1184static int omap8250_remove(struct platform_device *pdev)
1185{
1186	struct omap8250_priv *priv = platform_get_drvdata(pdev);
1187
1188	pm_runtime_put_sync(&pdev->dev);
1189	pm_runtime_disable(&pdev->dev);
1190	serial8250_unregister_port(priv->line);
1191	pm_qos_remove_request(&priv->pm_qos_request);
1192	device_init_wakeup(&pdev->dev, false);
1193	return 0;
1194}
1195
1196#ifdef CONFIG_PM
1197
1198static inline void omap8250_enable_wakeirq(struct omap8250_priv *priv,
1199					   bool enable)
1200{
1201	if (!priv->wakeirq)
1202		return;
1203
1204	if (enable)
1205		enable_irq(priv->wakeirq);
1206	else
1207		disable_irq_nosync(priv->wakeirq);
1208}
1209
1210static void omap8250_enable_wakeup(struct omap8250_priv *priv,
1211				   bool enable)
1212{
1213	if (enable == priv->wakeups_enabled)
1214		return;
1215
1216	omap8250_enable_wakeirq(priv, enable);
1217	priv->wakeups_enabled = enable;
1218}
1219#endif
1220
1221#ifdef CONFIG_PM_SLEEP
1222static int omap8250_prepare(struct device *dev)
1223{
1224	struct omap8250_priv *priv = dev_get_drvdata(dev);
1225
1226	if (!priv)
1227		return 0;
1228	priv->is_suspending = true;
1229	return 0;
1230}
1231
1232static void omap8250_complete(struct device *dev)
1233{
1234	struct omap8250_priv *priv = dev_get_drvdata(dev);
1235
1236	if (!priv)
1237		return;
1238	priv->is_suspending = false;
1239}
1240
1241static int omap8250_suspend(struct device *dev)
1242{
1243	struct omap8250_priv *priv = dev_get_drvdata(dev);
1244
1245	serial8250_suspend_port(priv->line);
1246	flush_work(&priv->qos_work);
1247
1248	if (device_may_wakeup(dev))
1249		omap8250_enable_wakeup(priv, true);
1250	else
1251		omap8250_enable_wakeup(priv, false);
1252	return 0;
1253}
1254
1255static int omap8250_resume(struct device *dev)
1256{
1257	struct omap8250_priv *priv = dev_get_drvdata(dev);
1258
1259	if (device_may_wakeup(dev))
1260		omap8250_enable_wakeup(priv, false);
1261
1262	serial8250_resume_port(priv->line);
1263	return 0;
1264}
1265#else
1266#define omap8250_prepare NULL
1267#define omap8250_complete NULL
1268#endif
1269
1270#ifdef CONFIG_PM
1271static int omap8250_lost_context(struct uart_8250_port *up)
1272{
1273	u32 val;
1274
1275	val = serial_in(up, UART_OMAP_MDR1);
1276	/*
1277	 * If we lose context, then MDR1 is set to its reset value which is
1278	 * UART_OMAP_MDR1_DISABLE. After set_termios() we set it either to 13x
1279	 * or 16x but never to disable again.
1280	 */
1281	if (val == UART_OMAP_MDR1_DISABLE)
1282		return 1;
1283	return 0;
1284}
1285
1286static int omap8250_runtime_suspend(struct device *dev)
1287{
1288	struct omap8250_priv *priv = dev_get_drvdata(dev);
1289	struct uart_8250_port *up;
1290
1291	up = serial8250_get_port(priv->line);
1292	/*
1293	 * When using 'no_console_suspend', the console UART must not be
1294	 * suspended. Since driver suspend is managed by runtime suspend,
1295	 * preventing runtime suspend (by returning error) will keep device
1296	 * active during suspend.
1297	 */
1298	if (priv->is_suspending && !console_suspend_enabled) {
1299		if (uart_console(&up->port))
1300			return -EBUSY;
1301	}
1302
1303	omap8250_enable_wakeup(priv, true);
1304	if (up->dma)
1305		omap_8250_rx_dma(up, UART_IIR_RX_TIMEOUT);
1306
1307	priv->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1308	schedule_work(&priv->qos_work);
1309
1310	return 0;
1311}
1312
1313static int omap8250_runtime_resume(struct device *dev)
1314{
1315	struct omap8250_priv *priv = dev_get_drvdata(dev);
1316	struct uart_8250_port *up;
1317	int loss_cntx;
1318
1319	/* In case runtime-pm tries this before we are setup */
1320	if (!priv)
1321		return 0;
1322
1323	up = serial8250_get_port(priv->line);
1324	omap8250_enable_wakeup(priv, false);
1325	loss_cntx = omap8250_lost_context(up);
1326
1327	if (loss_cntx)
1328		omap8250_restore_regs(up);
1329
1330	if (up->dma)
1331		omap_8250_rx_dma(up, 0);
1332
1333	priv->latency = priv->calc_latency;
1334	schedule_work(&priv->qos_work);
1335	return 0;
1336}
1337#endif
1338
1339#ifdef CONFIG_SERIAL_8250_OMAP_TTYO_FIXUP
1340static int __init omap8250_console_fixup(void)
1341{
1342	char *omap_str;
1343	char *options;
1344	u8 idx;
1345
1346	if (strstr(boot_command_line, "console=ttyS"))
1347		/* user set a ttyS based name for the console */
1348		return 0;
1349
1350	omap_str = strstr(boot_command_line, "console=ttyO");
1351	if (!omap_str)
1352		/* user did not set ttyO based console, so we don't care */
1353		return 0;
1354
1355	omap_str += 12;
1356	if ('0' <= *omap_str && *omap_str <= '9')
1357		idx = *omap_str - '0';
1358	else
1359		return 0;
1360
1361	omap_str++;
1362	if (omap_str[0] == ',') {
1363		omap_str++;
1364		options = omap_str;
1365	} else {
1366		options = NULL;
1367	}
1368
1369	add_preferred_console("ttyS", idx, options);
1370	pr_err("WARNING: Your 'console=ttyO%d' has been replaced by 'ttyS%d'\n",
1371	       idx, idx);
1372	pr_err("This ensures that you still see kernel messages. Please\n");
1373	pr_err("update your kernel commandline.\n");
1374	return 0;
1375}
1376console_initcall(omap8250_console_fixup);
1377#endif
1378
1379static const struct dev_pm_ops omap8250_dev_pm_ops = {
1380	SET_SYSTEM_SLEEP_PM_OPS(omap8250_suspend, omap8250_resume)
1381	SET_RUNTIME_PM_OPS(omap8250_runtime_suspend,
1382			   omap8250_runtime_resume, NULL)
1383	.prepare        = omap8250_prepare,
1384	.complete       = omap8250_complete,
1385};
1386
1387static const struct of_device_id omap8250_dt_ids[] = {
1388	{ .compatible = "ti,omap2-uart" },
1389	{ .compatible = "ti,omap3-uart" },
1390	{ .compatible = "ti,omap4-uart" },
1391	{},
1392};
1393MODULE_DEVICE_TABLE(of, omap8250_dt_ids);
1394
1395static struct platform_driver omap8250_platform_driver = {
1396	.driver = {
1397		.name		= "omap8250",
1398		.pm		= &omap8250_dev_pm_ops,
1399		.of_match_table = omap8250_dt_ids,
1400	},
1401	.probe			= omap8250_probe,
1402	.remove			= omap8250_remove,
1403};
1404module_platform_driver(omap8250_platform_driver);
1405
1406MODULE_AUTHOR("Sebastian Andrzej Siewior");
1407MODULE_DESCRIPTION("OMAP 8250 Driver");
1408MODULE_LICENSE("GPL v2");
1409