1/*
2 *  NXP (Philips) SCC+++(SCN+++) serial driver
3 *
4 *  Copyright (C) 2012 Alexander Shiyan <shc_work@mail.ru>
5 *
6 *  Based on sc26xx.c, by Thomas Bogend��rfer (tsbogend@alpha.franken.de)
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 */
13
14#if defined(CONFIG_SERIAL_SCCNXP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
15#define SUPPORT_SYSRQ
16#endif
17
18#include <linux/clk.h>
19#include <linux/err.h>
20#include <linux/module.h>
21#include <linux/device.h>
22#include <linux/console.h>
23#include <linux/serial_core.h>
24#include <linux/serial.h>
25#include <linux/io.h>
26#include <linux/tty.h>
27#include <linux/tty_flip.h>
28#include <linux/spinlock.h>
29#include <linux/platform_device.h>
30#include <linux/platform_data/serial-sccnxp.h>
31#include <linux/regulator/consumer.h>
32
33#define SCCNXP_NAME			"uart-sccnxp"
34#define SCCNXP_MAJOR			204
35#define SCCNXP_MINOR			205
36
37#define SCCNXP_MR_REG			(0x00)
38#	define MR0_BAUD_NORMAL		(0 << 0)
39#	define MR0_BAUD_EXT1		(1 << 0)
40#	define MR0_BAUD_EXT2		(5 << 0)
41#	define MR0_FIFO			(1 << 3)
42#	define MR0_TXLVL		(1 << 4)
43#	define MR1_BITS_5		(0 << 0)
44#	define MR1_BITS_6		(1 << 0)
45#	define MR1_BITS_7		(2 << 0)
46#	define MR1_BITS_8		(3 << 0)
47#	define MR1_PAR_EVN		(0 << 2)
48#	define MR1_PAR_ODD		(1 << 2)
49#	define MR1_PAR_NO		(4 << 2)
50#	define MR2_STOP1		(7 << 0)
51#	define MR2_STOP2		(0xf << 0)
52#define SCCNXP_SR_REG			(0x01)
53#define SCCNXP_CSR_REG			SCCNXP_SR_REG
54#	define SR_RXRDY			(1 << 0)
55#	define SR_FULL			(1 << 1)
56#	define SR_TXRDY			(1 << 2)
57#	define SR_TXEMT			(1 << 3)
58#	define SR_OVR			(1 << 4)
59#	define SR_PE			(1 << 5)
60#	define SR_FE			(1 << 6)
61#	define SR_BRK			(1 << 7)
62#define SCCNXP_CR_REG			(0x02)
63#	define CR_RX_ENABLE		(1 << 0)
64#	define CR_RX_DISABLE		(1 << 1)
65#	define CR_TX_ENABLE		(1 << 2)
66#	define CR_TX_DISABLE		(1 << 3)
67#	define CR_CMD_MRPTR1		(0x01 << 4)
68#	define CR_CMD_RX_RESET		(0x02 << 4)
69#	define CR_CMD_TX_RESET		(0x03 << 4)
70#	define CR_CMD_STATUS_RESET	(0x04 << 4)
71#	define CR_CMD_BREAK_RESET	(0x05 << 4)
72#	define CR_CMD_START_BREAK	(0x06 << 4)
73#	define CR_CMD_STOP_BREAK	(0x07 << 4)
74#	define CR_CMD_MRPTR0		(0x0b << 4)
75#define SCCNXP_RHR_REG			(0x03)
76#define SCCNXP_THR_REG			SCCNXP_RHR_REG
77#define SCCNXP_IPCR_REG			(0x04)
78#define SCCNXP_ACR_REG			SCCNXP_IPCR_REG
79#	define ACR_BAUD0		(0 << 7)
80#	define ACR_BAUD1		(1 << 7)
81#	define ACR_TIMER_MODE		(6 << 4)
82#define SCCNXP_ISR_REG			(0x05)
83#define SCCNXP_IMR_REG			SCCNXP_ISR_REG
84#	define IMR_TXRDY		(1 << 0)
85#	define IMR_RXRDY		(1 << 1)
86#	define ISR_TXRDY(x)		(1 << ((x * 4) + 0))
87#	define ISR_RXRDY(x)		(1 << ((x * 4) + 1))
88#define SCCNXP_IPR_REG			(0x0d)
89#define SCCNXP_OPCR_REG			SCCNXP_IPR_REG
90#define SCCNXP_SOP_REG			(0x0e)
91#define SCCNXP_ROP_REG			(0x0f)
92
93/* Route helpers */
94#define MCTRL_MASK(sig)			(0xf << (sig))
95#define MCTRL_IBIT(cfg, sig)		((((cfg) >> (sig)) & 0xf) - LINE_IP0)
96#define MCTRL_OBIT(cfg, sig)		((((cfg) >> (sig)) & 0xf) - LINE_OP0)
97
98#define SCCNXP_HAVE_IO		0x00000001
99#define SCCNXP_HAVE_MR0		0x00000002
100
101struct sccnxp_chip {
102	const char		*name;
103	unsigned int		nr;
104	unsigned long		freq_min;
105	unsigned long		freq_std;
106	unsigned long		freq_max;
107	unsigned int		flags;
108	unsigned int		fifosize;
109};
110
111struct sccnxp_port {
112	struct uart_driver	uart;
113	struct uart_port	port[SCCNXP_MAX_UARTS];
114	bool			opened[SCCNXP_MAX_UARTS];
115
116	int			irq;
117	u8			imr;
118
119	struct sccnxp_chip	*chip;
120
121#ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
122	struct console		console;
123#endif
124
125	spinlock_t		lock;
126
127	bool			poll;
128	struct timer_list	timer;
129
130	struct sccnxp_pdata	pdata;
131
132	struct regulator	*regulator;
133};
134
135static const struct sccnxp_chip sc2681 = {
136	.name		= "SC2681",
137	.nr		= 2,
138	.freq_min	= 1000000,
139	.freq_std	= 3686400,
140	.freq_max	= 4000000,
141	.flags		= SCCNXP_HAVE_IO,
142	.fifosize	= 3,
143};
144
145static const struct sccnxp_chip sc2691 = {
146	.name		= "SC2691",
147	.nr		= 1,
148	.freq_min	= 1000000,
149	.freq_std	= 3686400,
150	.freq_max	= 4000000,
151	.flags		= 0,
152	.fifosize	= 3,
153};
154
155static const struct sccnxp_chip sc2692 = {
156	.name		= "SC2692",
157	.nr		= 2,
158	.freq_min	= 1000000,
159	.freq_std	= 3686400,
160	.freq_max	= 4000000,
161	.flags		= SCCNXP_HAVE_IO,
162	.fifosize	= 3,
163};
164
165static const struct sccnxp_chip sc2891 = {
166	.name		= "SC2891",
167	.nr		= 1,
168	.freq_min	= 100000,
169	.freq_std	= 3686400,
170	.freq_max	= 8000000,
171	.flags		= SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0,
172	.fifosize	= 16,
173};
174
175static const struct sccnxp_chip sc2892 = {
176	.name		= "SC2892",
177	.nr		= 2,
178	.freq_min	= 100000,
179	.freq_std	= 3686400,
180	.freq_max	= 8000000,
181	.flags		= SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0,
182	.fifosize	= 16,
183};
184
185static const struct sccnxp_chip sc28202 = {
186	.name		= "SC28202",
187	.nr		= 2,
188	.freq_min	= 1000000,
189	.freq_std	= 14745600,
190	.freq_max	= 50000000,
191	.flags		= SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0,
192	.fifosize	= 256,
193};
194
195static const struct sccnxp_chip sc68681 = {
196	.name		= "SC68681",
197	.nr		= 2,
198	.freq_min	= 1000000,
199	.freq_std	= 3686400,
200	.freq_max	= 4000000,
201	.flags		= SCCNXP_HAVE_IO,
202	.fifosize	= 3,
203};
204
205static const struct sccnxp_chip sc68692 = {
206	.name		= "SC68692",
207	.nr		= 2,
208	.freq_min	= 1000000,
209	.freq_std	= 3686400,
210	.freq_max	= 4000000,
211	.flags		= SCCNXP_HAVE_IO,
212	.fifosize	= 3,
213};
214
215static inline u8 sccnxp_read(struct uart_port *port, u8 reg)
216{
217	return readb(port->membase + (reg << port->regshift));
218}
219
220static inline void sccnxp_write(struct uart_port *port, u8 reg, u8 v)
221{
222	writeb(v, port->membase + (reg << port->regshift));
223}
224
225static inline u8 sccnxp_port_read(struct uart_port *port, u8 reg)
226{
227	return sccnxp_read(port, (port->line << 3) + reg);
228}
229
230static inline void sccnxp_port_write(struct uart_port *port, u8 reg, u8 v)
231{
232	sccnxp_write(port, (port->line << 3) + reg, v);
233}
234
235static int sccnxp_update_best_err(int a, int b, int *besterr)
236{
237	int err = abs(a - b);
238
239	if ((*besterr < 0) || (*besterr > err)) {
240		*besterr = err;
241		return 0;
242	}
243
244	return 1;
245}
246
247static const struct {
248	u8	csr;
249	u8	acr;
250	u8	mr0;
251	int	baud;
252} baud_std[] = {
253	{ 0,	ACR_BAUD0,	MR0_BAUD_NORMAL,	50, },
254	{ 0,	ACR_BAUD1,	MR0_BAUD_NORMAL,	75, },
255	{ 1,	ACR_BAUD0,	MR0_BAUD_NORMAL,	110, },
256	{ 2,	ACR_BAUD0,	MR0_BAUD_NORMAL,	134, },
257	{ 3,	ACR_BAUD1,	MR0_BAUD_NORMAL,	150, },
258	{ 3,	ACR_BAUD0,	MR0_BAUD_NORMAL,	200, },
259	{ 4,	ACR_BAUD0,	MR0_BAUD_NORMAL,	300, },
260	{ 0,	ACR_BAUD1,	MR0_BAUD_EXT1,		450, },
261	{ 1,	ACR_BAUD0,	MR0_BAUD_EXT2,		880, },
262	{ 3,	ACR_BAUD1,	MR0_BAUD_EXT1,		900, },
263	{ 5,	ACR_BAUD0,	MR0_BAUD_NORMAL,	600, },
264	{ 7,	ACR_BAUD0,	MR0_BAUD_NORMAL,	1050, },
265	{ 2,	ACR_BAUD0,	MR0_BAUD_EXT2,		1076, },
266	{ 6,	ACR_BAUD0,	MR0_BAUD_NORMAL,	1200, },
267	{ 10,	ACR_BAUD1,	MR0_BAUD_NORMAL,	1800, },
268	{ 7,	ACR_BAUD1,	MR0_BAUD_NORMAL,	2000, },
269	{ 8,	ACR_BAUD0,	MR0_BAUD_NORMAL,	2400, },
270	{ 5,	ACR_BAUD1,	MR0_BAUD_EXT1,		3600, },
271	{ 9,	ACR_BAUD0,	MR0_BAUD_NORMAL,	4800, },
272	{ 10,	ACR_BAUD0,	MR0_BAUD_NORMAL,	7200, },
273	{ 11,	ACR_BAUD0,	MR0_BAUD_NORMAL,	9600, },
274	{ 8,	ACR_BAUD0,	MR0_BAUD_EXT1,		14400, },
275	{ 12,	ACR_BAUD1,	MR0_BAUD_NORMAL,	19200, },
276	{ 9,	ACR_BAUD0,	MR0_BAUD_EXT1,		28800, },
277	{ 12,	ACR_BAUD0,	MR0_BAUD_NORMAL,	38400, },
278	{ 11,	ACR_BAUD0,	MR0_BAUD_EXT1,		57600, },
279	{ 12,	ACR_BAUD1,	MR0_BAUD_EXT1,		115200, },
280	{ 12,	ACR_BAUD0,	MR0_BAUD_EXT1,		230400, },
281	{ 0, 0, 0, 0 }
282};
283
284static int sccnxp_set_baud(struct uart_port *port, int baud)
285{
286	struct sccnxp_port *s = dev_get_drvdata(port->dev);
287	int div_std, tmp_baud, bestbaud = baud, besterr = -1;
288	struct sccnxp_chip *chip = s->chip;
289	u8 i, acr = 0, csr = 0, mr0 = 0;
290
291	/* Find best baud from table */
292	for (i = 0; baud_std[i].baud && besterr; i++) {
293		if (baud_std[i].mr0 && !(chip->flags & SCCNXP_HAVE_MR0))
294			continue;
295		div_std = DIV_ROUND_CLOSEST(chip->freq_std, baud_std[i].baud);
296		tmp_baud = DIV_ROUND_CLOSEST(port->uartclk, div_std);
297		if (!sccnxp_update_best_err(baud, tmp_baud, &besterr)) {
298			acr = baud_std[i].acr;
299			csr = baud_std[i].csr;
300			mr0 = baud_std[i].mr0;
301			bestbaud = tmp_baud;
302		}
303	}
304
305	if (chip->flags & SCCNXP_HAVE_MR0) {
306		/* Enable FIFO, set half level for TX */
307		mr0 |= MR0_FIFO | MR0_TXLVL;
308		/* Update MR0 */
309		sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_MRPTR0);
310		sccnxp_port_write(port, SCCNXP_MR_REG, mr0);
311	}
312
313	sccnxp_port_write(port, SCCNXP_ACR_REG, acr | ACR_TIMER_MODE);
314	sccnxp_port_write(port, SCCNXP_CSR_REG, (csr << 4) | csr);
315
316	if (baud != bestbaud)
317		dev_dbg(port->dev, "Baudrate desired: %i, calculated: %i\n",
318			baud, bestbaud);
319
320	return bestbaud;
321}
322
323static void sccnxp_enable_irq(struct uart_port *port, int mask)
324{
325	struct sccnxp_port *s = dev_get_drvdata(port->dev);
326
327	s->imr |= mask << (port->line * 4);
328	sccnxp_write(port, SCCNXP_IMR_REG, s->imr);
329}
330
331static void sccnxp_disable_irq(struct uart_port *port, int mask)
332{
333	struct sccnxp_port *s = dev_get_drvdata(port->dev);
334
335	s->imr &= ~(mask << (port->line * 4));
336	sccnxp_write(port, SCCNXP_IMR_REG, s->imr);
337}
338
339static void sccnxp_set_bit(struct uart_port *port, int sig, int state)
340{
341	u8 bitmask;
342	struct sccnxp_port *s = dev_get_drvdata(port->dev);
343
344	if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(sig)) {
345		bitmask = 1 << MCTRL_OBIT(s->pdata.mctrl_cfg[port->line], sig);
346		if (state)
347			sccnxp_write(port, SCCNXP_SOP_REG, bitmask);
348		else
349			sccnxp_write(port, SCCNXP_ROP_REG, bitmask);
350	}
351}
352
353static void sccnxp_handle_rx(struct uart_port *port)
354{
355	u8 sr;
356	unsigned int ch, flag;
357
358	for (;;) {
359		sr = sccnxp_port_read(port, SCCNXP_SR_REG);
360		if (!(sr & SR_RXRDY))
361			break;
362		sr &= SR_PE | SR_FE | SR_OVR | SR_BRK;
363
364		ch = sccnxp_port_read(port, SCCNXP_RHR_REG);
365
366		port->icount.rx++;
367		flag = TTY_NORMAL;
368
369		if (unlikely(sr)) {
370			if (sr & SR_BRK) {
371				port->icount.brk++;
372				sccnxp_port_write(port, SCCNXP_CR_REG,
373						  CR_CMD_BREAK_RESET);
374				if (uart_handle_break(port))
375					continue;
376			} else if (sr & SR_PE)
377				port->icount.parity++;
378			else if (sr & SR_FE)
379				port->icount.frame++;
380			else if (sr & SR_OVR) {
381				port->icount.overrun++;
382				sccnxp_port_write(port, SCCNXP_CR_REG,
383						  CR_CMD_STATUS_RESET);
384			}
385
386			sr &= port->read_status_mask;
387			if (sr & SR_BRK)
388				flag = TTY_BREAK;
389			else if (sr & SR_PE)
390				flag = TTY_PARITY;
391			else if (sr & SR_FE)
392				flag = TTY_FRAME;
393			else if (sr & SR_OVR)
394				flag = TTY_OVERRUN;
395		}
396
397		if (uart_handle_sysrq_char(port, ch))
398			continue;
399
400		if (sr & port->ignore_status_mask)
401			continue;
402
403		uart_insert_char(port, sr, SR_OVR, ch, flag);
404	}
405
406	tty_flip_buffer_push(&port->state->port);
407}
408
409static void sccnxp_handle_tx(struct uart_port *port)
410{
411	u8 sr;
412	struct circ_buf *xmit = &port->state->xmit;
413	struct sccnxp_port *s = dev_get_drvdata(port->dev);
414
415	if (unlikely(port->x_char)) {
416		sccnxp_port_write(port, SCCNXP_THR_REG, port->x_char);
417		port->icount.tx++;
418		port->x_char = 0;
419		return;
420	}
421
422	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
423		/* Disable TX if FIFO is empty */
424		if (sccnxp_port_read(port, SCCNXP_SR_REG) & SR_TXEMT) {
425			sccnxp_disable_irq(port, IMR_TXRDY);
426
427			/* Set direction to input */
428			if (s->chip->flags & SCCNXP_HAVE_IO)
429				sccnxp_set_bit(port, DIR_OP, 0);
430		}
431		return;
432	}
433
434	while (!uart_circ_empty(xmit)) {
435		sr = sccnxp_port_read(port, SCCNXP_SR_REG);
436		if (!(sr & SR_TXRDY))
437			break;
438
439		sccnxp_port_write(port, SCCNXP_THR_REG, xmit->buf[xmit->tail]);
440		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
441		port->icount.tx++;
442	}
443
444	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
445		uart_write_wakeup(port);
446}
447
448static void sccnxp_handle_events(struct sccnxp_port *s)
449{
450	int i;
451	u8 isr;
452
453	do {
454		isr = sccnxp_read(&s->port[0], SCCNXP_ISR_REG);
455		isr &= s->imr;
456		if (!isr)
457			break;
458
459		for (i = 0; i < s->uart.nr; i++) {
460			if (s->opened[i] && (isr & ISR_RXRDY(i)))
461				sccnxp_handle_rx(&s->port[i]);
462			if (s->opened[i] && (isr & ISR_TXRDY(i)))
463				sccnxp_handle_tx(&s->port[i]);
464		}
465	} while (1);
466}
467
468static void sccnxp_timer(unsigned long data)
469{
470	struct sccnxp_port *s = (struct sccnxp_port *)data;
471	unsigned long flags;
472
473	spin_lock_irqsave(&s->lock, flags);
474	sccnxp_handle_events(s);
475	spin_unlock_irqrestore(&s->lock, flags);
476
477	mod_timer(&s->timer, jiffies + usecs_to_jiffies(s->pdata.poll_time_us));
478}
479
480static irqreturn_t sccnxp_ist(int irq, void *dev_id)
481{
482	struct sccnxp_port *s = (struct sccnxp_port *)dev_id;
483	unsigned long flags;
484
485	spin_lock_irqsave(&s->lock, flags);
486	sccnxp_handle_events(s);
487	spin_unlock_irqrestore(&s->lock, flags);
488
489	return IRQ_HANDLED;
490}
491
492static void sccnxp_start_tx(struct uart_port *port)
493{
494	struct sccnxp_port *s = dev_get_drvdata(port->dev);
495	unsigned long flags;
496
497	spin_lock_irqsave(&s->lock, flags);
498
499	/* Set direction to output */
500	if (s->chip->flags & SCCNXP_HAVE_IO)
501		sccnxp_set_bit(port, DIR_OP, 1);
502
503	sccnxp_enable_irq(port, IMR_TXRDY);
504
505	spin_unlock_irqrestore(&s->lock, flags);
506}
507
508static void sccnxp_stop_tx(struct uart_port *port)
509{
510	/* Do nothing */
511}
512
513static void sccnxp_stop_rx(struct uart_port *port)
514{
515	struct sccnxp_port *s = dev_get_drvdata(port->dev);
516	unsigned long flags;
517
518	spin_lock_irqsave(&s->lock, flags);
519	sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_DISABLE);
520	spin_unlock_irqrestore(&s->lock, flags);
521}
522
523static unsigned int sccnxp_tx_empty(struct uart_port *port)
524{
525	u8 val;
526	unsigned long flags;
527	struct sccnxp_port *s = dev_get_drvdata(port->dev);
528
529	spin_lock_irqsave(&s->lock, flags);
530	val = sccnxp_port_read(port, SCCNXP_SR_REG);
531	spin_unlock_irqrestore(&s->lock, flags);
532
533	return (val & SR_TXEMT) ? TIOCSER_TEMT : 0;
534}
535
536static void sccnxp_set_mctrl(struct uart_port *port, unsigned int mctrl)
537{
538	struct sccnxp_port *s = dev_get_drvdata(port->dev);
539	unsigned long flags;
540
541	if (!(s->chip->flags & SCCNXP_HAVE_IO))
542		return;
543
544	spin_lock_irqsave(&s->lock, flags);
545
546	sccnxp_set_bit(port, DTR_OP, mctrl & TIOCM_DTR);
547	sccnxp_set_bit(port, RTS_OP, mctrl & TIOCM_RTS);
548
549	spin_unlock_irqrestore(&s->lock, flags);
550}
551
552static unsigned int sccnxp_get_mctrl(struct uart_port *port)
553{
554	u8 bitmask, ipr;
555	unsigned long flags;
556	struct sccnxp_port *s = dev_get_drvdata(port->dev);
557	unsigned int mctrl = TIOCM_DSR | TIOCM_CTS | TIOCM_CAR;
558
559	if (!(s->chip->flags & SCCNXP_HAVE_IO))
560		return mctrl;
561
562	spin_lock_irqsave(&s->lock, flags);
563
564	ipr = ~sccnxp_read(port, SCCNXP_IPCR_REG);
565
566	if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(DSR_IP)) {
567		bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
568					  DSR_IP);
569		mctrl &= ~TIOCM_DSR;
570		mctrl |= (ipr & bitmask) ? TIOCM_DSR : 0;
571	}
572	if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(CTS_IP)) {
573		bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
574					  CTS_IP);
575		mctrl &= ~TIOCM_CTS;
576		mctrl |= (ipr & bitmask) ? TIOCM_CTS : 0;
577	}
578	if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(DCD_IP)) {
579		bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
580					  DCD_IP);
581		mctrl &= ~TIOCM_CAR;
582		mctrl |= (ipr & bitmask) ? TIOCM_CAR : 0;
583	}
584	if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(RNG_IP)) {
585		bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
586					  RNG_IP);
587		mctrl &= ~TIOCM_RNG;
588		mctrl |= (ipr & bitmask) ? TIOCM_RNG : 0;
589	}
590
591	spin_unlock_irqrestore(&s->lock, flags);
592
593	return mctrl;
594}
595
596static void sccnxp_break_ctl(struct uart_port *port, int break_state)
597{
598	struct sccnxp_port *s = dev_get_drvdata(port->dev);
599	unsigned long flags;
600
601	spin_lock_irqsave(&s->lock, flags);
602	sccnxp_port_write(port, SCCNXP_CR_REG, break_state ?
603			  CR_CMD_START_BREAK : CR_CMD_STOP_BREAK);
604	spin_unlock_irqrestore(&s->lock, flags);
605}
606
607static void sccnxp_set_termios(struct uart_port *port,
608			       struct ktermios *termios, struct ktermios *old)
609{
610	struct sccnxp_port *s = dev_get_drvdata(port->dev);
611	unsigned long flags;
612	u8 mr1, mr2;
613	int baud;
614
615	spin_lock_irqsave(&s->lock, flags);
616
617	/* Mask termios capabilities we don't support */
618	termios->c_cflag &= ~CMSPAR;
619
620	/* Disable RX & TX, reset break condition, status and FIFOs */
621	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_RX_RESET |
622					       CR_RX_DISABLE | CR_TX_DISABLE);
623	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_TX_RESET);
624	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_STATUS_RESET);
625	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_BREAK_RESET);
626
627	/* Word size */
628	switch (termios->c_cflag & CSIZE) {
629	case CS5:
630		mr1 = MR1_BITS_5;
631		break;
632	case CS6:
633		mr1 = MR1_BITS_6;
634		break;
635	case CS7:
636		mr1 = MR1_BITS_7;
637		break;
638	case CS8:
639	default:
640		mr1 = MR1_BITS_8;
641		break;
642	}
643
644	/* Parity */
645	if (termios->c_cflag & PARENB) {
646		if (termios->c_cflag & PARODD)
647			mr1 |= MR1_PAR_ODD;
648	} else
649		mr1 |= MR1_PAR_NO;
650
651	/* Stop bits */
652	mr2 = (termios->c_cflag & CSTOPB) ? MR2_STOP2 : MR2_STOP1;
653
654	/* Update desired format */
655	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_MRPTR1);
656	sccnxp_port_write(port, SCCNXP_MR_REG, mr1);
657	sccnxp_port_write(port, SCCNXP_MR_REG, mr2);
658
659	/* Set read status mask */
660	port->read_status_mask = SR_OVR;
661	if (termios->c_iflag & INPCK)
662		port->read_status_mask |= SR_PE | SR_FE;
663	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
664		port->read_status_mask |= SR_BRK;
665
666	/* Set status ignore mask */
667	port->ignore_status_mask = 0;
668	if (termios->c_iflag & IGNBRK)
669		port->ignore_status_mask |= SR_BRK;
670	if (termios->c_iflag & IGNPAR)
671		port->ignore_status_mask |= SR_PE;
672	if (!(termios->c_cflag & CREAD))
673		port->ignore_status_mask |= SR_PE | SR_OVR | SR_FE | SR_BRK;
674
675	/* Setup baudrate */
676	baud = uart_get_baud_rate(port, termios, old, 50,
677				  (s->chip->flags & SCCNXP_HAVE_MR0) ?
678				  230400 : 38400);
679	baud = sccnxp_set_baud(port, baud);
680
681	/* Update timeout according to new baud rate */
682	uart_update_timeout(port, termios->c_cflag, baud);
683
684	/* Report actual baudrate back to core */
685	if (tty_termios_baud_rate(termios))
686		tty_termios_encode_baud_rate(termios, baud, baud);
687
688	/* Enable RX & TX */
689	sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_ENABLE | CR_TX_ENABLE);
690
691	spin_unlock_irqrestore(&s->lock, flags);
692}
693
694static int sccnxp_startup(struct uart_port *port)
695{
696	struct sccnxp_port *s = dev_get_drvdata(port->dev);
697	unsigned long flags;
698
699	spin_lock_irqsave(&s->lock, flags);
700
701	if (s->chip->flags & SCCNXP_HAVE_IO) {
702		/* Outputs are controlled manually */
703		sccnxp_write(port, SCCNXP_OPCR_REG, 0);
704	}
705
706	/* Reset break condition, status and FIFOs */
707	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_RX_RESET);
708	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_TX_RESET);
709	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_STATUS_RESET);
710	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_BREAK_RESET);
711
712	/* Enable RX & TX */
713	sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_ENABLE | CR_TX_ENABLE);
714
715	/* Enable RX interrupt */
716	sccnxp_enable_irq(port, IMR_RXRDY);
717
718	s->opened[port->line] = 1;
719
720	spin_unlock_irqrestore(&s->lock, flags);
721
722	return 0;
723}
724
725static void sccnxp_shutdown(struct uart_port *port)
726{
727	struct sccnxp_port *s = dev_get_drvdata(port->dev);
728	unsigned long flags;
729
730	spin_lock_irqsave(&s->lock, flags);
731
732	s->opened[port->line] = 0;
733
734	/* Disable interrupts */
735	sccnxp_disable_irq(port, IMR_TXRDY | IMR_RXRDY);
736
737	/* Disable TX & RX */
738	sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_DISABLE | CR_TX_DISABLE);
739
740	/* Leave direction to input */
741	if (s->chip->flags & SCCNXP_HAVE_IO)
742		sccnxp_set_bit(port, DIR_OP, 0);
743
744	spin_unlock_irqrestore(&s->lock, flags);
745}
746
747static const char *sccnxp_type(struct uart_port *port)
748{
749	struct sccnxp_port *s = dev_get_drvdata(port->dev);
750
751	return (port->type == PORT_SC26XX) ? s->chip->name : NULL;
752}
753
754static void sccnxp_release_port(struct uart_port *port)
755{
756	/* Do nothing */
757}
758
759static int sccnxp_request_port(struct uart_port *port)
760{
761	/* Do nothing */
762	return 0;
763}
764
765static void sccnxp_config_port(struct uart_port *port, int flags)
766{
767	if (flags & UART_CONFIG_TYPE)
768		port->type = PORT_SC26XX;
769}
770
771static int sccnxp_verify_port(struct uart_port *port, struct serial_struct *s)
772{
773	if ((s->type == PORT_UNKNOWN) || (s->type == PORT_SC26XX))
774		return 0;
775	if (s->irq == port->irq)
776		return 0;
777
778	return -EINVAL;
779}
780
781static const struct uart_ops sccnxp_ops = {
782	.tx_empty	= sccnxp_tx_empty,
783	.set_mctrl	= sccnxp_set_mctrl,
784	.get_mctrl	= sccnxp_get_mctrl,
785	.stop_tx	= sccnxp_stop_tx,
786	.start_tx	= sccnxp_start_tx,
787	.stop_rx	= sccnxp_stop_rx,
788	.break_ctl	= sccnxp_break_ctl,
789	.startup	= sccnxp_startup,
790	.shutdown	= sccnxp_shutdown,
791	.set_termios	= sccnxp_set_termios,
792	.type		= sccnxp_type,
793	.release_port	= sccnxp_release_port,
794	.request_port	= sccnxp_request_port,
795	.config_port	= sccnxp_config_port,
796	.verify_port	= sccnxp_verify_port,
797};
798
799#ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
800static void sccnxp_console_putchar(struct uart_port *port, int c)
801{
802	int tryes = 100000;
803
804	while (tryes--) {
805		if (sccnxp_port_read(port, SCCNXP_SR_REG) & SR_TXRDY) {
806			sccnxp_port_write(port, SCCNXP_THR_REG, c);
807			break;
808		}
809		barrier();
810	}
811}
812
813static void sccnxp_console_write(struct console *co, const char *c, unsigned n)
814{
815	struct sccnxp_port *s = (struct sccnxp_port *)co->data;
816	struct uart_port *port = &s->port[co->index];
817	unsigned long flags;
818
819	spin_lock_irqsave(&s->lock, flags);
820	uart_console_write(port, c, n, sccnxp_console_putchar);
821	spin_unlock_irqrestore(&s->lock, flags);
822}
823
824static int sccnxp_console_setup(struct console *co, char *options)
825{
826	struct sccnxp_port *s = (struct sccnxp_port *)co->data;
827	struct uart_port *port = &s->port[(co->index > 0) ? co->index : 0];
828	int baud = 9600, bits = 8, parity = 'n', flow = 'n';
829
830	if (options)
831		uart_parse_options(options, &baud, &parity, &bits, &flow);
832
833	return uart_set_options(port, co, baud, parity, bits, flow);
834}
835#endif
836
837static const struct platform_device_id sccnxp_id_table[] = {
838	{ .name = "sc2681",	.driver_data = (kernel_ulong_t)&sc2681, },
839	{ .name = "sc2691",	.driver_data = (kernel_ulong_t)&sc2691, },
840	{ .name = "sc2692",	.driver_data = (kernel_ulong_t)&sc2692, },
841	{ .name = "sc2891",	.driver_data = (kernel_ulong_t)&sc2891, },
842	{ .name = "sc2892",	.driver_data = (kernel_ulong_t)&sc2892, },
843	{ .name = "sc28202",	.driver_data = (kernel_ulong_t)&sc28202, },
844	{ .name = "sc68681",	.driver_data = (kernel_ulong_t)&sc68681, },
845	{ .name = "sc68692",	.driver_data = (kernel_ulong_t)&sc68692, },
846	{ }
847};
848MODULE_DEVICE_TABLE(platform, sccnxp_id_table);
849
850static int sccnxp_probe(struct platform_device *pdev)
851{
852	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
853	struct sccnxp_pdata *pdata = dev_get_platdata(&pdev->dev);
854	int i, ret, uartclk;
855	struct sccnxp_port *s;
856	void __iomem *membase;
857	struct clk *clk;
858
859	membase = devm_ioremap_resource(&pdev->dev, res);
860	if (IS_ERR(membase))
861		return PTR_ERR(membase);
862
863	s = devm_kzalloc(&pdev->dev, sizeof(struct sccnxp_port), GFP_KERNEL);
864	if (!s) {
865		dev_err(&pdev->dev, "Error allocating port structure\n");
866		return -ENOMEM;
867	}
868	platform_set_drvdata(pdev, s);
869
870	spin_lock_init(&s->lock);
871
872	s->chip = (struct sccnxp_chip *)pdev->id_entry->driver_data;
873
874	s->regulator = devm_regulator_get(&pdev->dev, "vcc");
875	if (!IS_ERR(s->regulator)) {
876		ret = regulator_enable(s->regulator);
877		if (ret) {
878			dev_err(&pdev->dev,
879				"Failed to enable regulator: %i\n", ret);
880			return ret;
881		}
882	} else if (PTR_ERR(s->regulator) == -EPROBE_DEFER)
883		return -EPROBE_DEFER;
884
885	clk = devm_clk_get(&pdev->dev, NULL);
886	if (IS_ERR(clk)) {
887		if (PTR_ERR(clk) == -EPROBE_DEFER) {
888			ret = -EPROBE_DEFER;
889			goto err_out;
890		}
891		dev_notice(&pdev->dev, "Using default clock frequency\n");
892		uartclk = s->chip->freq_std;
893	} else
894		uartclk = clk_get_rate(clk);
895
896	/* Check input frequency */
897	if ((uartclk < s->chip->freq_min) || (uartclk > s->chip->freq_max)) {
898		dev_err(&pdev->dev, "Frequency out of bounds\n");
899		ret = -EINVAL;
900		goto err_out;
901	}
902
903	if (pdata)
904		memcpy(&s->pdata, pdata, sizeof(struct sccnxp_pdata));
905
906	if (s->pdata.poll_time_us) {
907		dev_info(&pdev->dev, "Using poll mode, resolution %u usecs\n",
908			 s->pdata.poll_time_us);
909		s->poll = 1;
910	}
911
912	if (!s->poll) {
913		s->irq = platform_get_irq(pdev, 0);
914		if (s->irq < 0) {
915			dev_err(&pdev->dev, "Missing irq resource data\n");
916			ret = -ENXIO;
917			goto err_out;
918		}
919	}
920
921	s->uart.owner		= THIS_MODULE;
922	s->uart.dev_name	= "ttySC";
923	s->uart.major		= SCCNXP_MAJOR;
924	s->uart.minor		= SCCNXP_MINOR;
925	s->uart.nr		= s->chip->nr;
926#ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
927	s->uart.cons		= &s->console;
928	s->uart.cons->device	= uart_console_device;
929	s->uart.cons->write	= sccnxp_console_write;
930	s->uart.cons->setup	= sccnxp_console_setup;
931	s->uart.cons->flags	= CON_PRINTBUFFER;
932	s->uart.cons->index	= -1;
933	s->uart.cons->data	= s;
934	strcpy(s->uart.cons->name, "ttySC");
935#endif
936	ret = uart_register_driver(&s->uart);
937	if (ret) {
938		dev_err(&pdev->dev, "Registering UART driver failed\n");
939		goto err_out;
940	}
941
942	for (i = 0; i < s->uart.nr; i++) {
943		s->port[i].line		= i;
944		s->port[i].dev		= &pdev->dev;
945		s->port[i].irq		= s->irq;
946		s->port[i].type		= PORT_SC26XX;
947		s->port[i].fifosize	= s->chip->fifosize;
948		s->port[i].flags	= UPF_SKIP_TEST | UPF_FIXED_TYPE;
949		s->port[i].iotype	= UPIO_MEM;
950		s->port[i].mapbase	= res->start;
951		s->port[i].membase	= membase;
952		s->port[i].regshift	= s->pdata.reg_shift;
953		s->port[i].uartclk	= uartclk;
954		s->port[i].ops		= &sccnxp_ops;
955		uart_add_one_port(&s->uart, &s->port[i]);
956		/* Set direction to input */
957		if (s->chip->flags & SCCNXP_HAVE_IO)
958			sccnxp_set_bit(&s->port[i], DIR_OP, 0);
959	}
960
961	/* Disable interrupts */
962	s->imr = 0;
963	sccnxp_write(&s->port[0], SCCNXP_IMR_REG, 0);
964
965	if (!s->poll) {
966		ret = devm_request_threaded_irq(&pdev->dev, s->irq, NULL,
967						sccnxp_ist,
968						IRQF_TRIGGER_FALLING |
969						IRQF_ONESHOT,
970						dev_name(&pdev->dev), s);
971		if (!ret)
972			return 0;
973
974		dev_err(&pdev->dev, "Unable to reguest IRQ %i\n", s->irq);
975	} else {
976		init_timer(&s->timer);
977		setup_timer(&s->timer, sccnxp_timer, (unsigned long)s);
978		mod_timer(&s->timer, jiffies +
979			  usecs_to_jiffies(s->pdata.poll_time_us));
980		return 0;
981	}
982
983	uart_unregister_driver(&s->uart);
984err_out:
985	if (!IS_ERR(s->regulator))
986		return regulator_disable(s->regulator);
987
988	return ret;
989}
990
991static int sccnxp_remove(struct platform_device *pdev)
992{
993	int i;
994	struct sccnxp_port *s = platform_get_drvdata(pdev);
995
996	if (!s->poll)
997		devm_free_irq(&pdev->dev, s->irq, s);
998	else
999		del_timer_sync(&s->timer);
1000
1001	for (i = 0; i < s->uart.nr; i++)
1002		uart_remove_one_port(&s->uart, &s->port[i]);
1003
1004	uart_unregister_driver(&s->uart);
1005
1006	if (!IS_ERR(s->regulator))
1007		return regulator_disable(s->regulator);
1008
1009	return 0;
1010}
1011
1012static struct platform_driver sccnxp_uart_driver = {
1013	.driver = {
1014		.name	= SCCNXP_NAME,
1015	},
1016	.probe		= sccnxp_probe,
1017	.remove		= sccnxp_remove,
1018	.id_table	= sccnxp_id_table,
1019};
1020module_platform_driver(sccnxp_uart_driver);
1021
1022MODULE_LICENSE("GPL v2");
1023MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
1024MODULE_DESCRIPTION("SCCNXP serial driver");
1025