xref: /openbmc/linux/drivers/tty/serial/sh-sci.c (revision 260ea95c)
1 /*
2  * SuperH on-chip serial module support.  (SCI with no FIFO / with FIFO)
3  *
4  *  Copyright (C) 2002 - 2011  Paul Mundt
5  *  Copyright (C) 2015 Glider bvba
6  *  Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
7  *
8  * based off of the old drivers/char/sh-sci.c by:
9  *
10  *   Copyright (C) 1999, 2000  Niibe Yutaka
11  *   Copyright (C) 2000  Sugioka Toshinobu
12  *   Modified to support multiple serial ports. Stuart Menefy (May 2000).
13  *   Modified to support SecureEdge. David McCullough (2002)
14  *   Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003).
15  *   Removed SH7300 support (Jul 2007).
16  *
17  * This file is subject to the terms and conditions of the GNU General Public
18  * License.  See the file "COPYING" in the main directory of this archive
19  * for more details.
20  */
21 #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
22 #define SUPPORT_SYSRQ
23 #endif
24 
25 #undef DEBUG
26 
27 #include <linux/clk.h>
28 #include <linux/console.h>
29 #include <linux/ctype.h>
30 #include <linux/cpufreq.h>
31 #include <linux/delay.h>
32 #include <linux/dmaengine.h>
33 #include <linux/dma-mapping.h>
34 #include <linux/err.h>
35 #include <linux/errno.h>
36 #include <linux/init.h>
37 #include <linux/interrupt.h>
38 #include <linux/ioport.h>
39 #include <linux/major.h>
40 #include <linux/module.h>
41 #include <linux/mm.h>
42 #include <linux/of.h>
43 #include <linux/platform_device.h>
44 #include <linux/pm_runtime.h>
45 #include <linux/scatterlist.h>
46 #include <linux/serial.h>
47 #include <linux/serial_sci.h>
48 #include <linux/sh_dma.h>
49 #include <linux/slab.h>
50 #include <linux/string.h>
51 #include <linux/sysrq.h>
52 #include <linux/timer.h>
53 #include <linux/tty.h>
54 #include <linux/tty_flip.h>
55 
56 #ifdef CONFIG_SUPERH
57 #include <asm/sh_bios.h>
58 #endif
59 
60 #include "serial_mctrl_gpio.h"
61 #include "sh-sci.h"
62 
63 /* Offsets into the sci_port->irqs array */
64 enum {
65 	SCIx_ERI_IRQ,
66 	SCIx_RXI_IRQ,
67 	SCIx_TXI_IRQ,
68 	SCIx_BRI_IRQ,
69 	SCIx_NR_IRQS,
70 
71 	SCIx_MUX_IRQ = SCIx_NR_IRQS,	/* special case */
72 };
73 
74 #define SCIx_IRQ_IS_MUXED(port)			\
75 	((port)->irqs[SCIx_ERI_IRQ] ==	\
76 	 (port)->irqs[SCIx_RXI_IRQ]) ||	\
77 	((port)->irqs[SCIx_ERI_IRQ] &&	\
78 	 ((port)->irqs[SCIx_RXI_IRQ] < 0))
79 
80 enum SCI_CLKS {
81 	SCI_FCK,		/* Functional Clock */
82 	SCI_SCK,		/* Optional External Clock */
83 	SCI_BRG_INT,		/* Optional BRG Internal Clock Source */
84 	SCI_SCIF_CLK,		/* Optional BRG External Clock Source */
85 	SCI_NUM_CLKS
86 };
87 
88 /* Bit x set means sampling rate x + 1 is supported */
89 #define SCI_SR(x)		BIT((x) - 1)
90 #define SCI_SR_RANGE(x, y)	GENMASK((y) - 1, (x) - 1)
91 
92 #define SCI_SR_SCIFAB		SCI_SR(5) | SCI_SR(7) | SCI_SR(11) | \
93 				SCI_SR(13) | SCI_SR(16) | SCI_SR(17) | \
94 				SCI_SR(19) | SCI_SR(27)
95 
96 #define min_sr(_port)		ffs((_port)->sampling_rate_mask)
97 #define max_sr(_port)		fls((_port)->sampling_rate_mask)
98 
99 /* Iterate over all supported sampling rates, from high to low */
100 #define for_each_sr(_sr, _port)						\
101 	for ((_sr) = max_sr(_port); (_sr) >= min_sr(_port); (_sr)--)	\
102 		if ((_port)->sampling_rate_mask & SCI_SR((_sr)))
103 
104 struct plat_sci_reg {
105 	u8 offset, size;
106 };
107 
108 struct sci_port_params {
109 	const struct plat_sci_reg regs[SCIx_NR_REGS];
110 	unsigned int fifosize;
111 	unsigned int overrun_reg;
112 	unsigned int overrun_mask;
113 	unsigned int sampling_rate_mask;
114 	unsigned int error_mask;
115 	unsigned int error_clear;
116 };
117 
118 struct sci_port {
119 	struct uart_port	port;
120 
121 	/* Platform configuration */
122 	const struct sci_port_params *params;
123 	const struct plat_sci_port *cfg;
124 	unsigned int		sampling_rate_mask;
125 	resource_size_t		reg_size;
126 	struct mctrl_gpios	*gpios;
127 
128 	/* Clocks */
129 	struct clk		*clks[SCI_NUM_CLKS];
130 	unsigned long		clk_rates[SCI_NUM_CLKS];
131 
132 	int			irqs[SCIx_NR_IRQS];
133 	char			*irqstr[SCIx_NR_IRQS];
134 
135 	struct dma_chan			*chan_tx;
136 	struct dma_chan			*chan_rx;
137 
138 #ifdef CONFIG_SERIAL_SH_SCI_DMA
139 	dma_cookie_t			cookie_tx;
140 	dma_cookie_t			cookie_rx[2];
141 	dma_cookie_t			active_rx;
142 	dma_addr_t			tx_dma_addr;
143 	unsigned int			tx_dma_len;
144 	struct scatterlist		sg_rx[2];
145 	void				*rx_buf[2];
146 	size_t				buf_len_rx;
147 	struct work_struct		work_tx;
148 	struct timer_list		rx_timer;
149 	unsigned int			rx_timeout;
150 #endif
151 	unsigned int			rx_frame;
152 	int				rx_trigger;
153 	struct timer_list		rx_fifo_timer;
154 	int				rx_fifo_timeout;
155 
156 	bool has_rtscts;
157 	bool autorts;
158 };
159 
160 #define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
161 
162 static struct sci_port sci_ports[SCI_NPORTS];
163 static struct uart_driver sci_uart_driver;
164 
165 static inline struct sci_port *
166 to_sci_port(struct uart_port *uart)
167 {
168 	return container_of(uart, struct sci_port, port);
169 }
170 
171 static const struct sci_port_params sci_port_params[SCIx_NR_REGTYPES] = {
172 	/*
173 	 * Common SCI definitions, dependent on the port's regshift
174 	 * value.
175 	 */
176 	[SCIx_SCI_REGTYPE] = {
177 		.regs = {
178 			[SCSMR]		= { 0x00,  8 },
179 			[SCBRR]		= { 0x01,  8 },
180 			[SCSCR]		= { 0x02,  8 },
181 			[SCxTDR]	= { 0x03,  8 },
182 			[SCxSR]		= { 0x04,  8 },
183 			[SCxRDR]	= { 0x05,  8 },
184 		},
185 		.fifosize = 1,
186 		.overrun_reg = SCxSR,
187 		.overrun_mask = SCI_ORER,
188 		.sampling_rate_mask = SCI_SR(32),
189 		.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
190 		.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
191 	},
192 
193 	/*
194 	 * Common definitions for legacy IrDA ports.
195 	 */
196 	[SCIx_IRDA_REGTYPE] = {
197 		.regs = {
198 			[SCSMR]		= { 0x00,  8 },
199 			[SCBRR]		= { 0x02,  8 },
200 			[SCSCR]		= { 0x04,  8 },
201 			[SCxTDR]	= { 0x06,  8 },
202 			[SCxSR]		= { 0x08, 16 },
203 			[SCxRDR]	= { 0x0a,  8 },
204 			[SCFCR]		= { 0x0c,  8 },
205 			[SCFDR]		= { 0x0e, 16 },
206 		},
207 		.fifosize = 1,
208 		.overrun_reg = SCxSR,
209 		.overrun_mask = SCI_ORER,
210 		.sampling_rate_mask = SCI_SR(32),
211 		.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
212 		.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
213 	},
214 
215 	/*
216 	 * Common SCIFA definitions.
217 	 */
218 	[SCIx_SCIFA_REGTYPE] = {
219 		.regs = {
220 			[SCSMR]		= { 0x00, 16 },
221 			[SCBRR]		= { 0x04,  8 },
222 			[SCSCR]		= { 0x08, 16 },
223 			[SCxTDR]	= { 0x20,  8 },
224 			[SCxSR]		= { 0x14, 16 },
225 			[SCxRDR]	= { 0x24,  8 },
226 			[SCFCR]		= { 0x18, 16 },
227 			[SCFDR]		= { 0x1c, 16 },
228 			[SCPCR]		= { 0x30, 16 },
229 			[SCPDR]		= { 0x34, 16 },
230 		},
231 		.fifosize = 64,
232 		.overrun_reg = SCxSR,
233 		.overrun_mask = SCIFA_ORER,
234 		.sampling_rate_mask = SCI_SR_SCIFAB,
235 		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
236 		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
237 	},
238 
239 	/*
240 	 * Common SCIFB definitions.
241 	 */
242 	[SCIx_SCIFB_REGTYPE] = {
243 		.regs = {
244 			[SCSMR]		= { 0x00, 16 },
245 			[SCBRR]		= { 0x04,  8 },
246 			[SCSCR]		= { 0x08, 16 },
247 			[SCxTDR]	= { 0x40,  8 },
248 			[SCxSR]		= { 0x14, 16 },
249 			[SCxRDR]	= { 0x60,  8 },
250 			[SCFCR]		= { 0x18, 16 },
251 			[SCTFDR]	= { 0x38, 16 },
252 			[SCRFDR]	= { 0x3c, 16 },
253 			[SCPCR]		= { 0x30, 16 },
254 			[SCPDR]		= { 0x34, 16 },
255 		},
256 		.fifosize = 256,
257 		.overrun_reg = SCxSR,
258 		.overrun_mask = SCIFA_ORER,
259 		.sampling_rate_mask = SCI_SR_SCIFAB,
260 		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
261 		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
262 	},
263 
264 	/*
265 	 * Common SH-2(A) SCIF definitions for ports with FIFO data
266 	 * count registers.
267 	 */
268 	[SCIx_SH2_SCIF_FIFODATA_REGTYPE] = {
269 		.regs = {
270 			[SCSMR]		= { 0x00, 16 },
271 			[SCBRR]		= { 0x04,  8 },
272 			[SCSCR]		= { 0x08, 16 },
273 			[SCxTDR]	= { 0x0c,  8 },
274 			[SCxSR]		= { 0x10, 16 },
275 			[SCxRDR]	= { 0x14,  8 },
276 			[SCFCR]		= { 0x18, 16 },
277 			[SCFDR]		= { 0x1c, 16 },
278 			[SCSPTR]	= { 0x20, 16 },
279 			[SCLSR]		= { 0x24, 16 },
280 		},
281 		.fifosize = 16,
282 		.overrun_reg = SCLSR,
283 		.overrun_mask = SCLSR_ORER,
284 		.sampling_rate_mask = SCI_SR(32),
285 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
286 		.error_clear = SCIF_ERROR_CLEAR,
287 	},
288 
289 	/*
290 	 * Common SH-3 SCIF definitions.
291 	 */
292 	[SCIx_SH3_SCIF_REGTYPE] = {
293 		.regs = {
294 			[SCSMR]		= { 0x00,  8 },
295 			[SCBRR]		= { 0x02,  8 },
296 			[SCSCR]		= { 0x04,  8 },
297 			[SCxTDR]	= { 0x06,  8 },
298 			[SCxSR]		= { 0x08, 16 },
299 			[SCxRDR]	= { 0x0a,  8 },
300 			[SCFCR]		= { 0x0c,  8 },
301 			[SCFDR]		= { 0x0e, 16 },
302 		},
303 		.fifosize = 16,
304 		.overrun_reg = SCLSR,
305 		.overrun_mask = SCLSR_ORER,
306 		.sampling_rate_mask = SCI_SR(32),
307 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
308 		.error_clear = SCIF_ERROR_CLEAR,
309 	},
310 
311 	/*
312 	 * Common SH-4(A) SCIF(B) definitions.
313 	 */
314 	[SCIx_SH4_SCIF_REGTYPE] = {
315 		.regs = {
316 			[SCSMR]		= { 0x00, 16 },
317 			[SCBRR]		= { 0x04,  8 },
318 			[SCSCR]		= { 0x08, 16 },
319 			[SCxTDR]	= { 0x0c,  8 },
320 			[SCxSR]		= { 0x10, 16 },
321 			[SCxRDR]	= { 0x14,  8 },
322 			[SCFCR]		= { 0x18, 16 },
323 			[SCFDR]		= { 0x1c, 16 },
324 			[SCSPTR]	= { 0x20, 16 },
325 			[SCLSR]		= { 0x24, 16 },
326 		},
327 		.fifosize = 16,
328 		.overrun_reg = SCLSR,
329 		.overrun_mask = SCLSR_ORER,
330 		.sampling_rate_mask = SCI_SR(32),
331 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
332 		.error_clear = SCIF_ERROR_CLEAR,
333 	},
334 
335 	/*
336 	 * Common SCIF definitions for ports with a Baud Rate Generator for
337 	 * External Clock (BRG).
338 	 */
339 	[SCIx_SH4_SCIF_BRG_REGTYPE] = {
340 		.regs = {
341 			[SCSMR]		= { 0x00, 16 },
342 			[SCBRR]		= { 0x04,  8 },
343 			[SCSCR]		= { 0x08, 16 },
344 			[SCxTDR]	= { 0x0c,  8 },
345 			[SCxSR]		= { 0x10, 16 },
346 			[SCxRDR]	= { 0x14,  8 },
347 			[SCFCR]		= { 0x18, 16 },
348 			[SCFDR]		= { 0x1c, 16 },
349 			[SCSPTR]	= { 0x20, 16 },
350 			[SCLSR]		= { 0x24, 16 },
351 			[SCDL]		= { 0x30, 16 },
352 			[SCCKS]		= { 0x34, 16 },
353 		},
354 		.fifosize = 16,
355 		.overrun_reg = SCLSR,
356 		.overrun_mask = SCLSR_ORER,
357 		.sampling_rate_mask = SCI_SR(32),
358 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
359 		.error_clear = SCIF_ERROR_CLEAR,
360 	},
361 
362 	/*
363 	 * Common HSCIF definitions.
364 	 */
365 	[SCIx_HSCIF_REGTYPE] = {
366 		.regs = {
367 			[SCSMR]		= { 0x00, 16 },
368 			[SCBRR]		= { 0x04,  8 },
369 			[SCSCR]		= { 0x08, 16 },
370 			[SCxTDR]	= { 0x0c,  8 },
371 			[SCxSR]		= { 0x10, 16 },
372 			[SCxRDR]	= { 0x14,  8 },
373 			[SCFCR]		= { 0x18, 16 },
374 			[SCFDR]		= { 0x1c, 16 },
375 			[SCSPTR]	= { 0x20, 16 },
376 			[SCLSR]		= { 0x24, 16 },
377 			[HSSRR]		= { 0x40, 16 },
378 			[SCDL]		= { 0x30, 16 },
379 			[SCCKS]		= { 0x34, 16 },
380 			[HSRTRGR]	= { 0x54, 16 },
381 			[HSTTRGR]	= { 0x58, 16 },
382 		},
383 		.fifosize = 128,
384 		.overrun_reg = SCLSR,
385 		.overrun_mask = SCLSR_ORER,
386 		.sampling_rate_mask = SCI_SR_RANGE(8, 32),
387 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
388 		.error_clear = SCIF_ERROR_CLEAR,
389 	},
390 
391 	/*
392 	 * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR
393 	 * register.
394 	 */
395 	[SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = {
396 		.regs = {
397 			[SCSMR]		= { 0x00, 16 },
398 			[SCBRR]		= { 0x04,  8 },
399 			[SCSCR]		= { 0x08, 16 },
400 			[SCxTDR]	= { 0x0c,  8 },
401 			[SCxSR]		= { 0x10, 16 },
402 			[SCxRDR]	= { 0x14,  8 },
403 			[SCFCR]		= { 0x18, 16 },
404 			[SCFDR]		= { 0x1c, 16 },
405 			[SCLSR]		= { 0x24, 16 },
406 		},
407 		.fifosize = 16,
408 		.overrun_reg = SCLSR,
409 		.overrun_mask = SCLSR_ORER,
410 		.sampling_rate_mask = SCI_SR(32),
411 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
412 		.error_clear = SCIF_ERROR_CLEAR,
413 	},
414 
415 	/*
416 	 * Common SH-4(A) SCIF(B) definitions for ports with FIFO data
417 	 * count registers.
418 	 */
419 	[SCIx_SH4_SCIF_FIFODATA_REGTYPE] = {
420 		.regs = {
421 			[SCSMR]		= { 0x00, 16 },
422 			[SCBRR]		= { 0x04,  8 },
423 			[SCSCR]		= { 0x08, 16 },
424 			[SCxTDR]	= { 0x0c,  8 },
425 			[SCxSR]		= { 0x10, 16 },
426 			[SCxRDR]	= { 0x14,  8 },
427 			[SCFCR]		= { 0x18, 16 },
428 			[SCFDR]		= { 0x1c, 16 },
429 			[SCTFDR]	= { 0x1c, 16 },	/* aliased to SCFDR */
430 			[SCRFDR]	= { 0x20, 16 },
431 			[SCSPTR]	= { 0x24, 16 },
432 			[SCLSR]		= { 0x28, 16 },
433 		},
434 		.fifosize = 16,
435 		.overrun_reg = SCLSR,
436 		.overrun_mask = SCLSR_ORER,
437 		.sampling_rate_mask = SCI_SR(32),
438 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
439 		.error_clear = SCIF_ERROR_CLEAR,
440 	},
441 
442 	/*
443 	 * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR
444 	 * registers.
445 	 */
446 	[SCIx_SH7705_SCIF_REGTYPE] = {
447 		.regs = {
448 			[SCSMR]		= { 0x00, 16 },
449 			[SCBRR]		= { 0x04,  8 },
450 			[SCSCR]		= { 0x08, 16 },
451 			[SCxTDR]	= { 0x20,  8 },
452 			[SCxSR]		= { 0x14, 16 },
453 			[SCxRDR]	= { 0x24,  8 },
454 			[SCFCR]		= { 0x18, 16 },
455 			[SCFDR]		= { 0x1c, 16 },
456 		},
457 		.fifosize = 64,
458 		.overrun_reg = SCxSR,
459 		.overrun_mask = SCIFA_ORER,
460 		.sampling_rate_mask = SCI_SR(16),
461 		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
462 		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
463 	},
464 };
465 
466 #define sci_getreg(up, offset)		(&to_sci_port(up)->params->regs[offset])
467 
468 /*
469  * The "offset" here is rather misleading, in that it refers to an enum
470  * value relative to the port mapping rather than the fixed offset
471  * itself, which needs to be manually retrieved from the platform's
472  * register map for the given port.
473  */
474 static unsigned int sci_serial_in(struct uart_port *p, int offset)
475 {
476 	const struct plat_sci_reg *reg = sci_getreg(p, offset);
477 
478 	if (reg->size == 8)
479 		return ioread8(p->membase + (reg->offset << p->regshift));
480 	else if (reg->size == 16)
481 		return ioread16(p->membase + (reg->offset << p->regshift));
482 	else
483 		WARN(1, "Invalid register access\n");
484 
485 	return 0;
486 }
487 
488 static void sci_serial_out(struct uart_port *p, int offset, int value)
489 {
490 	const struct plat_sci_reg *reg = sci_getreg(p, offset);
491 
492 	if (reg->size == 8)
493 		iowrite8(value, p->membase + (reg->offset << p->regshift));
494 	else if (reg->size == 16)
495 		iowrite16(value, p->membase + (reg->offset << p->regshift));
496 	else
497 		WARN(1, "Invalid register access\n");
498 }
499 
500 static void sci_port_enable(struct sci_port *sci_port)
501 {
502 	unsigned int i;
503 
504 	if (!sci_port->port.dev)
505 		return;
506 
507 	pm_runtime_get_sync(sci_port->port.dev);
508 
509 	for (i = 0; i < SCI_NUM_CLKS; i++) {
510 		clk_prepare_enable(sci_port->clks[i]);
511 		sci_port->clk_rates[i] = clk_get_rate(sci_port->clks[i]);
512 	}
513 	sci_port->port.uartclk = sci_port->clk_rates[SCI_FCK];
514 }
515 
516 static void sci_port_disable(struct sci_port *sci_port)
517 {
518 	unsigned int i;
519 
520 	if (!sci_port->port.dev)
521 		return;
522 
523 	for (i = SCI_NUM_CLKS; i-- > 0; )
524 		clk_disable_unprepare(sci_port->clks[i]);
525 
526 	pm_runtime_put_sync(sci_port->port.dev);
527 }
528 
529 static inline unsigned long port_rx_irq_mask(struct uart_port *port)
530 {
531 	/*
532 	 * Not all ports (such as SCIFA) will support REIE. Rather than
533 	 * special-casing the port type, we check the port initialization
534 	 * IRQ enable mask to see whether the IRQ is desired at all. If
535 	 * it's unset, it's logically inferred that there's no point in
536 	 * testing for it.
537 	 */
538 	return SCSCR_RIE | (to_sci_port(port)->cfg->scscr & SCSCR_REIE);
539 }
540 
541 static void sci_start_tx(struct uart_port *port)
542 {
543 	struct sci_port *s = to_sci_port(port);
544 	unsigned short ctrl;
545 
546 #ifdef CONFIG_SERIAL_SH_SCI_DMA
547 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
548 		u16 new, scr = serial_port_in(port, SCSCR);
549 		if (s->chan_tx)
550 			new = scr | SCSCR_TDRQE;
551 		else
552 			new = scr & ~SCSCR_TDRQE;
553 		if (new != scr)
554 			serial_port_out(port, SCSCR, new);
555 	}
556 
557 	if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
558 	    dma_submit_error(s->cookie_tx)) {
559 		s->cookie_tx = 0;
560 		schedule_work(&s->work_tx);
561 	}
562 #endif
563 
564 	if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
565 		/* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
566 		ctrl = serial_port_in(port, SCSCR);
567 		serial_port_out(port, SCSCR, ctrl | SCSCR_TIE);
568 	}
569 }
570 
571 static void sci_stop_tx(struct uart_port *port)
572 {
573 	unsigned short ctrl;
574 
575 	/* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
576 	ctrl = serial_port_in(port, SCSCR);
577 
578 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
579 		ctrl &= ~SCSCR_TDRQE;
580 
581 	ctrl &= ~SCSCR_TIE;
582 
583 	serial_port_out(port, SCSCR, ctrl);
584 }
585 
586 static void sci_start_rx(struct uart_port *port)
587 {
588 	unsigned short ctrl;
589 
590 	ctrl = serial_port_in(port, SCSCR) | port_rx_irq_mask(port);
591 
592 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
593 		ctrl &= ~SCSCR_RDRQE;
594 
595 	serial_port_out(port, SCSCR, ctrl);
596 }
597 
598 static void sci_stop_rx(struct uart_port *port)
599 {
600 	unsigned short ctrl;
601 
602 	ctrl = serial_port_in(port, SCSCR);
603 
604 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
605 		ctrl &= ~SCSCR_RDRQE;
606 
607 	ctrl &= ~port_rx_irq_mask(port);
608 
609 	serial_port_out(port, SCSCR, ctrl);
610 }
611 
612 static void sci_clear_SCxSR(struct uart_port *port, unsigned int mask)
613 {
614 	if (port->type == PORT_SCI) {
615 		/* Just store the mask */
616 		serial_port_out(port, SCxSR, mask);
617 	} else if (to_sci_port(port)->params->overrun_mask == SCIFA_ORER) {
618 		/* SCIFA/SCIFB and SCIF on SH7705/SH7720/SH7721 */
619 		/* Only clear the status bits we want to clear */
620 		serial_port_out(port, SCxSR,
621 				serial_port_in(port, SCxSR) & mask);
622 	} else {
623 		/* Store the mask, clear parity/framing errors */
624 		serial_port_out(port, SCxSR, mask & ~(SCIF_FERC | SCIF_PERC));
625 	}
626 }
627 
628 #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
629     defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
630 
631 #ifdef CONFIG_CONSOLE_POLL
632 static int sci_poll_get_char(struct uart_port *port)
633 {
634 	unsigned short status;
635 	int c;
636 
637 	do {
638 		status = serial_port_in(port, SCxSR);
639 		if (status & SCxSR_ERRORS(port)) {
640 			sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
641 			continue;
642 		}
643 		break;
644 	} while (1);
645 
646 	if (!(status & SCxSR_RDxF(port)))
647 		return NO_POLL_CHAR;
648 
649 	c = serial_port_in(port, SCxRDR);
650 
651 	/* Dummy read */
652 	serial_port_in(port, SCxSR);
653 	sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
654 
655 	return c;
656 }
657 #endif
658 
659 static void sci_poll_put_char(struct uart_port *port, unsigned char c)
660 {
661 	unsigned short status;
662 
663 	do {
664 		status = serial_port_in(port, SCxSR);
665 	} while (!(status & SCxSR_TDxE(port)));
666 
667 	serial_port_out(port, SCxTDR, c);
668 	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
669 }
670 #endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE ||
671 	  CONFIG_SERIAL_SH_SCI_EARLYCON */
672 
673 static void sci_init_pins(struct uart_port *port, unsigned int cflag)
674 {
675 	struct sci_port *s = to_sci_port(port);
676 
677 	/*
678 	 * Use port-specific handler if provided.
679 	 */
680 	if (s->cfg->ops && s->cfg->ops->init_pins) {
681 		s->cfg->ops->init_pins(port, cflag);
682 		return;
683 	}
684 
685 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
686 		u16 data = serial_port_in(port, SCPDR);
687 		u16 ctrl = serial_port_in(port, SCPCR);
688 
689 		/* Enable RXD and TXD pin functions */
690 		ctrl &= ~(SCPCR_RXDC | SCPCR_TXDC);
691 		if (to_sci_port(port)->has_rtscts) {
692 			/* RTS# is output, active low, unless autorts */
693 			if (!(port->mctrl & TIOCM_RTS)) {
694 				ctrl |= SCPCR_RTSC;
695 				data |= SCPDR_RTSD;
696 			} else if (!s->autorts) {
697 				ctrl |= SCPCR_RTSC;
698 				data &= ~SCPDR_RTSD;
699 			} else {
700 				/* Enable RTS# pin function */
701 				ctrl &= ~SCPCR_RTSC;
702 			}
703 			/* Enable CTS# pin function */
704 			ctrl &= ~SCPCR_CTSC;
705 		}
706 		serial_port_out(port, SCPDR, data);
707 		serial_port_out(port, SCPCR, ctrl);
708 	} else if (sci_getreg(port, SCSPTR)->size) {
709 		u16 status = serial_port_in(port, SCSPTR);
710 
711 		/* RTS# is always output; and active low, unless autorts */
712 		status |= SCSPTR_RTSIO;
713 		if (!(port->mctrl & TIOCM_RTS))
714 			status |= SCSPTR_RTSDT;
715 		else if (!s->autorts)
716 			status &= ~SCSPTR_RTSDT;
717 		/* CTS# and SCK are inputs */
718 		status &= ~(SCSPTR_CTSIO | SCSPTR_SCKIO);
719 		serial_port_out(port, SCSPTR, status);
720 	}
721 }
722 
723 static int sci_txfill(struct uart_port *port)
724 {
725 	struct sci_port *s = to_sci_port(port);
726 	unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
727 	const struct plat_sci_reg *reg;
728 
729 	reg = sci_getreg(port, SCTFDR);
730 	if (reg->size)
731 		return serial_port_in(port, SCTFDR) & fifo_mask;
732 
733 	reg = sci_getreg(port, SCFDR);
734 	if (reg->size)
735 		return serial_port_in(port, SCFDR) >> 8;
736 
737 	return !(serial_port_in(port, SCxSR) & SCI_TDRE);
738 }
739 
740 static int sci_txroom(struct uart_port *port)
741 {
742 	return port->fifosize - sci_txfill(port);
743 }
744 
745 static int sci_rxfill(struct uart_port *port)
746 {
747 	struct sci_port *s = to_sci_port(port);
748 	unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
749 	const struct plat_sci_reg *reg;
750 
751 	reg = sci_getreg(port, SCRFDR);
752 	if (reg->size)
753 		return serial_port_in(port, SCRFDR) & fifo_mask;
754 
755 	reg = sci_getreg(port, SCFDR);
756 	if (reg->size)
757 		return serial_port_in(port, SCFDR) & fifo_mask;
758 
759 	return (serial_port_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
760 }
761 
762 /* ********************************************************************** *
763  *                   the interrupt related routines                       *
764  * ********************************************************************** */
765 
766 static void sci_transmit_chars(struct uart_port *port)
767 {
768 	struct circ_buf *xmit = &port->state->xmit;
769 	unsigned int stopped = uart_tx_stopped(port);
770 	unsigned short status;
771 	unsigned short ctrl;
772 	int count;
773 
774 	status = serial_port_in(port, SCxSR);
775 	if (!(status & SCxSR_TDxE(port))) {
776 		ctrl = serial_port_in(port, SCSCR);
777 		if (uart_circ_empty(xmit))
778 			ctrl &= ~SCSCR_TIE;
779 		else
780 			ctrl |= SCSCR_TIE;
781 		serial_port_out(port, SCSCR, ctrl);
782 		return;
783 	}
784 
785 	count = sci_txroom(port);
786 
787 	do {
788 		unsigned char c;
789 
790 		if (port->x_char) {
791 			c = port->x_char;
792 			port->x_char = 0;
793 		} else if (!uart_circ_empty(xmit) && !stopped) {
794 			c = xmit->buf[xmit->tail];
795 			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
796 		} else {
797 			break;
798 		}
799 
800 		serial_port_out(port, SCxTDR, c);
801 
802 		port->icount.tx++;
803 	} while (--count > 0);
804 
805 	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
806 
807 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
808 		uart_write_wakeup(port);
809 	if (uart_circ_empty(xmit)) {
810 		sci_stop_tx(port);
811 	} else {
812 		ctrl = serial_port_in(port, SCSCR);
813 
814 		if (port->type != PORT_SCI) {
815 			serial_port_in(port, SCxSR); /* Dummy read */
816 			sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
817 		}
818 
819 		ctrl |= SCSCR_TIE;
820 		serial_port_out(port, SCSCR, ctrl);
821 	}
822 }
823 
824 /* On SH3, SCIF may read end-of-break as a space->mark char */
825 #define STEPFN(c)  ({int __c = (c); (((__c-1)|(__c)) == -1); })
826 
827 static void sci_receive_chars(struct uart_port *port)
828 {
829 	struct tty_port *tport = &port->state->port;
830 	int i, count, copied = 0;
831 	unsigned short status;
832 	unsigned char flag;
833 
834 	status = serial_port_in(port, SCxSR);
835 	if (!(status & SCxSR_RDxF(port)))
836 		return;
837 
838 	while (1) {
839 		/* Don't copy more bytes than there is room for in the buffer */
840 		count = tty_buffer_request_room(tport, sci_rxfill(port));
841 
842 		/* If for any reason we can't copy more data, we're done! */
843 		if (count == 0)
844 			break;
845 
846 		if (port->type == PORT_SCI) {
847 			char c = serial_port_in(port, SCxRDR);
848 			if (uart_handle_sysrq_char(port, c))
849 				count = 0;
850 			else
851 				tty_insert_flip_char(tport, c, TTY_NORMAL);
852 		} else {
853 			for (i = 0; i < count; i++) {
854 				char c = serial_port_in(port, SCxRDR);
855 
856 				status = serial_port_in(port, SCxSR);
857 				if (uart_handle_sysrq_char(port, c)) {
858 					count--; i--;
859 					continue;
860 				}
861 
862 				/* Store data and status */
863 				if (status & SCxSR_FER(port)) {
864 					flag = TTY_FRAME;
865 					port->icount.frame++;
866 					dev_notice(port->dev, "frame error\n");
867 				} else if (status & SCxSR_PER(port)) {
868 					flag = TTY_PARITY;
869 					port->icount.parity++;
870 					dev_notice(port->dev, "parity error\n");
871 				} else
872 					flag = TTY_NORMAL;
873 
874 				tty_insert_flip_char(tport, c, flag);
875 			}
876 		}
877 
878 		serial_port_in(port, SCxSR); /* dummy read */
879 		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
880 
881 		copied += count;
882 		port->icount.rx += count;
883 	}
884 
885 	if (copied) {
886 		/* Tell the rest of the system the news. New characters! */
887 		tty_flip_buffer_push(tport);
888 	} else {
889 		serial_port_in(port, SCxSR); /* dummy read */
890 		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
891 	}
892 }
893 
894 static int sci_handle_errors(struct uart_port *port)
895 {
896 	int copied = 0;
897 	unsigned short status = serial_port_in(port, SCxSR);
898 	struct tty_port *tport = &port->state->port;
899 	struct sci_port *s = to_sci_port(port);
900 
901 	/* Handle overruns */
902 	if (status & s->params->overrun_mask) {
903 		port->icount.overrun++;
904 
905 		/* overrun error */
906 		if (tty_insert_flip_char(tport, 0, TTY_OVERRUN))
907 			copied++;
908 
909 		dev_notice(port->dev, "overrun error\n");
910 	}
911 
912 	if (status & SCxSR_FER(port)) {
913 		/* frame error */
914 		port->icount.frame++;
915 
916 		if (tty_insert_flip_char(tport, 0, TTY_FRAME))
917 			copied++;
918 
919 		dev_notice(port->dev, "frame error\n");
920 	}
921 
922 	if (status & SCxSR_PER(port)) {
923 		/* parity error */
924 		port->icount.parity++;
925 
926 		if (tty_insert_flip_char(tport, 0, TTY_PARITY))
927 			copied++;
928 
929 		dev_notice(port->dev, "parity error\n");
930 	}
931 
932 	if (copied)
933 		tty_flip_buffer_push(tport);
934 
935 	return copied;
936 }
937 
938 static int sci_handle_fifo_overrun(struct uart_port *port)
939 {
940 	struct tty_port *tport = &port->state->port;
941 	struct sci_port *s = to_sci_port(port);
942 	const struct plat_sci_reg *reg;
943 	int copied = 0;
944 	u16 status;
945 
946 	reg = sci_getreg(port, s->params->overrun_reg);
947 	if (!reg->size)
948 		return 0;
949 
950 	status = serial_port_in(port, s->params->overrun_reg);
951 	if (status & s->params->overrun_mask) {
952 		status &= ~s->params->overrun_mask;
953 		serial_port_out(port, s->params->overrun_reg, status);
954 
955 		port->icount.overrun++;
956 
957 		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
958 		tty_flip_buffer_push(tport);
959 
960 		dev_dbg(port->dev, "overrun error\n");
961 		copied++;
962 	}
963 
964 	return copied;
965 }
966 
967 static int sci_handle_breaks(struct uart_port *port)
968 {
969 	int copied = 0;
970 	unsigned short status = serial_port_in(port, SCxSR);
971 	struct tty_port *tport = &port->state->port;
972 
973 	if (uart_handle_break(port))
974 		return 0;
975 
976 	if (status & SCxSR_BRK(port)) {
977 		port->icount.brk++;
978 
979 		/* Notify of BREAK */
980 		if (tty_insert_flip_char(tport, 0, TTY_BREAK))
981 			copied++;
982 
983 		dev_dbg(port->dev, "BREAK detected\n");
984 	}
985 
986 	if (copied)
987 		tty_flip_buffer_push(tport);
988 
989 	copied += sci_handle_fifo_overrun(port);
990 
991 	return copied;
992 }
993 
994 static int scif_set_rtrg(struct uart_port *port, int rx_trig)
995 {
996 	unsigned int bits;
997 
998 	if (rx_trig < 1)
999 		rx_trig = 1;
1000 	if (rx_trig >= port->fifosize)
1001 		rx_trig = port->fifosize;
1002 
1003 	/* HSCIF can be set to an arbitrary level. */
1004 	if (sci_getreg(port, HSRTRGR)->size) {
1005 		serial_port_out(port, HSRTRGR, rx_trig);
1006 		return rx_trig;
1007 	}
1008 
1009 	switch (port->type) {
1010 	case PORT_SCIF:
1011 		if (rx_trig < 4) {
1012 			bits = 0;
1013 			rx_trig = 1;
1014 		} else if (rx_trig < 8) {
1015 			bits = SCFCR_RTRG0;
1016 			rx_trig = 4;
1017 		} else if (rx_trig < 14) {
1018 			bits = SCFCR_RTRG1;
1019 			rx_trig = 8;
1020 		} else {
1021 			bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1022 			rx_trig = 14;
1023 		}
1024 		break;
1025 	case PORT_SCIFA:
1026 	case PORT_SCIFB:
1027 		if (rx_trig < 16) {
1028 			bits = 0;
1029 			rx_trig = 1;
1030 		} else if (rx_trig < 32) {
1031 			bits = SCFCR_RTRG0;
1032 			rx_trig = 16;
1033 		} else if (rx_trig < 48) {
1034 			bits = SCFCR_RTRG1;
1035 			rx_trig = 32;
1036 		} else {
1037 			bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1038 			rx_trig = 48;
1039 		}
1040 		break;
1041 	default:
1042 		WARN(1, "unknown FIFO configuration");
1043 		return 1;
1044 	}
1045 
1046 	serial_port_out(port, SCFCR,
1047 		(serial_port_in(port, SCFCR) &
1048 		~(SCFCR_RTRG1 | SCFCR_RTRG0)) | bits);
1049 
1050 	return rx_trig;
1051 }
1052 
1053 static int scif_rtrg_enabled(struct uart_port *port)
1054 {
1055 	if (sci_getreg(port, HSRTRGR)->size)
1056 		return serial_port_in(port, HSRTRGR) != 0;
1057 	else
1058 		return (serial_port_in(port, SCFCR) &
1059 			(SCFCR_RTRG0 | SCFCR_RTRG1)) != 0;
1060 }
1061 
1062 static void rx_fifo_timer_fn(unsigned long arg)
1063 {
1064 	struct sci_port *s = (struct sci_port *)arg;
1065 	struct uart_port *port = &s->port;
1066 
1067 	dev_dbg(port->dev, "Rx timed out\n");
1068 	scif_set_rtrg(port, 1);
1069 }
1070 
1071 static ssize_t rx_trigger_show(struct device *dev,
1072 			       struct device_attribute *attr,
1073 			       char *buf)
1074 {
1075 	struct uart_port *port = dev_get_drvdata(dev);
1076 	struct sci_port *sci = to_sci_port(port);
1077 
1078 	return sprintf(buf, "%d\n", sci->rx_trigger);
1079 }
1080 
1081 static ssize_t rx_trigger_store(struct device *dev,
1082 				struct device_attribute *attr,
1083 				const char *buf,
1084 				size_t count)
1085 {
1086 	struct uart_port *port = dev_get_drvdata(dev);
1087 	struct sci_port *sci = to_sci_port(port);
1088 	long r;
1089 
1090 	if (kstrtol(buf, 0, &r) == -EINVAL)
1091 		return -EINVAL;
1092 
1093 	sci->rx_trigger = scif_set_rtrg(port, r);
1094 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1095 		scif_set_rtrg(port, 1);
1096 
1097 	return count;
1098 }
1099 
1100 static DEVICE_ATTR(rx_fifo_trigger, 0644, rx_trigger_show, rx_trigger_store);
1101 
1102 static ssize_t rx_fifo_timeout_show(struct device *dev,
1103 			       struct device_attribute *attr,
1104 			       char *buf)
1105 {
1106 	struct uart_port *port = dev_get_drvdata(dev);
1107 	struct sci_port *sci = to_sci_port(port);
1108 
1109 	return sprintf(buf, "%d\n", sci->rx_fifo_timeout);
1110 }
1111 
1112 static ssize_t rx_fifo_timeout_store(struct device *dev,
1113 				struct device_attribute *attr,
1114 				const char *buf,
1115 				size_t count)
1116 {
1117 	struct uart_port *port = dev_get_drvdata(dev);
1118 	struct sci_port *sci = to_sci_port(port);
1119 	long r;
1120 
1121 	if (kstrtol(buf, 0, &r) == -EINVAL)
1122 		return -EINVAL;
1123 	sci->rx_fifo_timeout = r;
1124 	scif_set_rtrg(port, 1);
1125 	if (r > 0)
1126 		setup_timer(&sci->rx_fifo_timer, rx_fifo_timer_fn,
1127 			    (unsigned long)sci);
1128 	return count;
1129 }
1130 
1131 static DEVICE_ATTR(rx_fifo_timeout, 0644, rx_fifo_timeout_show, rx_fifo_timeout_store);
1132 
1133 
1134 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1135 static void sci_dma_tx_complete(void *arg)
1136 {
1137 	struct sci_port *s = arg;
1138 	struct uart_port *port = &s->port;
1139 	struct circ_buf *xmit = &port->state->xmit;
1140 	unsigned long flags;
1141 
1142 	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1143 
1144 	spin_lock_irqsave(&port->lock, flags);
1145 
1146 	xmit->tail += s->tx_dma_len;
1147 	xmit->tail &= UART_XMIT_SIZE - 1;
1148 
1149 	port->icount.tx += s->tx_dma_len;
1150 
1151 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1152 		uart_write_wakeup(port);
1153 
1154 	if (!uart_circ_empty(xmit)) {
1155 		s->cookie_tx = 0;
1156 		schedule_work(&s->work_tx);
1157 	} else {
1158 		s->cookie_tx = -EINVAL;
1159 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1160 			u16 ctrl = serial_port_in(port, SCSCR);
1161 			serial_port_out(port, SCSCR, ctrl & ~SCSCR_TIE);
1162 		}
1163 	}
1164 
1165 	spin_unlock_irqrestore(&port->lock, flags);
1166 }
1167 
1168 /* Locking: called with port lock held */
1169 static int sci_dma_rx_push(struct sci_port *s, void *buf, size_t count)
1170 {
1171 	struct uart_port *port = &s->port;
1172 	struct tty_port *tport = &port->state->port;
1173 	int copied;
1174 
1175 	copied = tty_insert_flip_string(tport, buf, count);
1176 	if (copied < count)
1177 		port->icount.buf_overrun++;
1178 
1179 	port->icount.rx += copied;
1180 
1181 	return copied;
1182 }
1183 
1184 static int sci_dma_rx_find_active(struct sci_port *s)
1185 {
1186 	unsigned int i;
1187 
1188 	for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1189 		if (s->active_rx == s->cookie_rx[i])
1190 			return i;
1191 
1192 	return -1;
1193 }
1194 
1195 static void sci_rx_dma_release(struct sci_port *s, bool enable_pio)
1196 {
1197 	struct dma_chan *chan = s->chan_rx;
1198 	struct uart_port *port = &s->port;
1199 	unsigned long flags;
1200 
1201 	spin_lock_irqsave(&port->lock, flags);
1202 	s->chan_rx = NULL;
1203 	s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL;
1204 	spin_unlock_irqrestore(&port->lock, flags);
1205 	dmaengine_terminate_all(chan);
1206 	dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0],
1207 			  sg_dma_address(&s->sg_rx[0]));
1208 	dma_release_channel(chan);
1209 	if (enable_pio)
1210 		sci_start_rx(port);
1211 }
1212 
1213 static void sci_dma_rx_complete(void *arg)
1214 {
1215 	struct sci_port *s = arg;
1216 	struct dma_chan *chan = s->chan_rx;
1217 	struct uart_port *port = &s->port;
1218 	struct dma_async_tx_descriptor *desc;
1219 	unsigned long flags;
1220 	int active, count = 0;
1221 
1222 	dev_dbg(port->dev, "%s(%d) active cookie %d\n", __func__, port->line,
1223 		s->active_rx);
1224 
1225 	spin_lock_irqsave(&port->lock, flags);
1226 
1227 	active = sci_dma_rx_find_active(s);
1228 	if (active >= 0)
1229 		count = sci_dma_rx_push(s, s->rx_buf[active], s->buf_len_rx);
1230 
1231 	mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
1232 
1233 	if (count)
1234 		tty_flip_buffer_push(&port->state->port);
1235 
1236 	desc = dmaengine_prep_slave_sg(s->chan_rx, &s->sg_rx[active], 1,
1237 				       DMA_DEV_TO_MEM,
1238 				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1239 	if (!desc)
1240 		goto fail;
1241 
1242 	desc->callback = sci_dma_rx_complete;
1243 	desc->callback_param = s;
1244 	s->cookie_rx[active] = dmaengine_submit(desc);
1245 	if (dma_submit_error(s->cookie_rx[active]))
1246 		goto fail;
1247 
1248 	s->active_rx = s->cookie_rx[!active];
1249 
1250 	dma_async_issue_pending(chan);
1251 
1252 	spin_unlock_irqrestore(&port->lock, flags);
1253 	dev_dbg(port->dev, "%s: cookie %d #%d, new active cookie %d\n",
1254 		__func__, s->cookie_rx[active], active, s->active_rx);
1255 	return;
1256 
1257 fail:
1258 	spin_unlock_irqrestore(&port->lock, flags);
1259 	dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
1260 	sci_rx_dma_release(s, true);
1261 }
1262 
1263 static void sci_tx_dma_release(struct sci_port *s, bool enable_pio)
1264 {
1265 	struct dma_chan *chan = s->chan_tx;
1266 	struct uart_port *port = &s->port;
1267 	unsigned long flags;
1268 
1269 	spin_lock_irqsave(&port->lock, flags);
1270 	s->chan_tx = NULL;
1271 	s->cookie_tx = -EINVAL;
1272 	spin_unlock_irqrestore(&port->lock, flags);
1273 	dmaengine_terminate_all(chan);
1274 	dma_unmap_single(chan->device->dev, s->tx_dma_addr, UART_XMIT_SIZE,
1275 			 DMA_TO_DEVICE);
1276 	dma_release_channel(chan);
1277 	if (enable_pio)
1278 		sci_start_tx(port);
1279 }
1280 
1281 static void sci_submit_rx(struct sci_port *s)
1282 {
1283 	struct dma_chan *chan = s->chan_rx;
1284 	int i;
1285 
1286 	for (i = 0; i < 2; i++) {
1287 		struct scatterlist *sg = &s->sg_rx[i];
1288 		struct dma_async_tx_descriptor *desc;
1289 
1290 		desc = dmaengine_prep_slave_sg(chan,
1291 			sg, 1, DMA_DEV_TO_MEM,
1292 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1293 		if (!desc)
1294 			goto fail;
1295 
1296 		desc->callback = sci_dma_rx_complete;
1297 		desc->callback_param = s;
1298 		s->cookie_rx[i] = dmaengine_submit(desc);
1299 		if (dma_submit_error(s->cookie_rx[i]))
1300 			goto fail;
1301 
1302 	}
1303 
1304 	s->active_rx = s->cookie_rx[0];
1305 
1306 	dma_async_issue_pending(chan);
1307 	return;
1308 
1309 fail:
1310 	if (i)
1311 		dmaengine_terminate_all(chan);
1312 	for (i = 0; i < 2; i++)
1313 		s->cookie_rx[i] = -EINVAL;
1314 	s->active_rx = -EINVAL;
1315 	sci_rx_dma_release(s, true);
1316 }
1317 
1318 static void work_fn_tx(struct work_struct *work)
1319 {
1320 	struct sci_port *s = container_of(work, struct sci_port, work_tx);
1321 	struct dma_async_tx_descriptor *desc;
1322 	struct dma_chan *chan = s->chan_tx;
1323 	struct uart_port *port = &s->port;
1324 	struct circ_buf *xmit = &port->state->xmit;
1325 	dma_addr_t buf;
1326 
1327 	/*
1328 	 * DMA is idle now.
1329 	 * Port xmit buffer is already mapped, and it is one page... Just adjust
1330 	 * offsets and lengths. Since it is a circular buffer, we have to
1331 	 * transmit till the end, and then the rest. Take the port lock to get a
1332 	 * consistent xmit buffer state.
1333 	 */
1334 	spin_lock_irq(&port->lock);
1335 	buf = s->tx_dma_addr + (xmit->tail & (UART_XMIT_SIZE - 1));
1336 	s->tx_dma_len = min_t(unsigned int,
1337 		CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE),
1338 		CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE));
1339 	spin_unlock_irq(&port->lock);
1340 
1341 	desc = dmaengine_prep_slave_single(chan, buf, s->tx_dma_len,
1342 					   DMA_MEM_TO_DEV,
1343 					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1344 	if (!desc) {
1345 		dev_warn(port->dev, "Failed preparing Tx DMA descriptor\n");
1346 		/* switch to PIO */
1347 		sci_tx_dma_release(s, true);
1348 		return;
1349 	}
1350 
1351 	dma_sync_single_for_device(chan->device->dev, buf, s->tx_dma_len,
1352 				   DMA_TO_DEVICE);
1353 
1354 	spin_lock_irq(&port->lock);
1355 	desc->callback = sci_dma_tx_complete;
1356 	desc->callback_param = s;
1357 	spin_unlock_irq(&port->lock);
1358 	s->cookie_tx = dmaengine_submit(desc);
1359 	if (dma_submit_error(s->cookie_tx)) {
1360 		dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
1361 		/* switch to PIO */
1362 		sci_tx_dma_release(s, true);
1363 		return;
1364 	}
1365 
1366 	dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n",
1367 		__func__, xmit->buf, xmit->tail, xmit->head, s->cookie_tx);
1368 
1369 	dma_async_issue_pending(chan);
1370 }
1371 
1372 static void rx_timer_fn(unsigned long arg)
1373 {
1374 	struct sci_port *s = (struct sci_port *)arg;
1375 	struct dma_chan *chan = s->chan_rx;
1376 	struct uart_port *port = &s->port;
1377 	struct dma_tx_state state;
1378 	enum dma_status status;
1379 	unsigned long flags;
1380 	unsigned int read;
1381 	int active, count;
1382 	u16 scr;
1383 
1384 	dev_dbg(port->dev, "DMA Rx timed out\n");
1385 
1386 	spin_lock_irqsave(&port->lock, flags);
1387 
1388 	active = sci_dma_rx_find_active(s);
1389 	if (active < 0) {
1390 		spin_unlock_irqrestore(&port->lock, flags);
1391 		return;
1392 	}
1393 
1394 	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1395 	if (status == DMA_COMPLETE) {
1396 		spin_unlock_irqrestore(&port->lock, flags);
1397 		dev_dbg(port->dev, "Cookie %d #%d has already completed\n",
1398 			s->active_rx, active);
1399 
1400 		/* Let packet complete handler take care of the packet */
1401 		return;
1402 	}
1403 
1404 	dmaengine_pause(chan);
1405 
1406 	/*
1407 	 * sometimes DMA transfer doesn't stop even if it is stopped and
1408 	 * data keeps on coming until transaction is complete so check
1409 	 * for DMA_COMPLETE again
1410 	 * Let packet complete handler take care of the packet
1411 	 */
1412 	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1413 	if (status == DMA_COMPLETE) {
1414 		spin_unlock_irqrestore(&port->lock, flags);
1415 		dev_dbg(port->dev, "Transaction complete after DMA engine was stopped");
1416 		return;
1417 	}
1418 
1419 	/* Handle incomplete DMA receive */
1420 	dmaengine_terminate_all(s->chan_rx);
1421 	read = sg_dma_len(&s->sg_rx[active]) - state.residue;
1422 
1423 	if (read) {
1424 		count = sci_dma_rx_push(s, s->rx_buf[active], read);
1425 		if (count)
1426 			tty_flip_buffer_push(&port->state->port);
1427 	}
1428 
1429 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1430 		sci_submit_rx(s);
1431 
1432 	/* Direct new serial port interrupts back to CPU */
1433 	scr = serial_port_in(port, SCSCR);
1434 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1435 		scr &= ~SCSCR_RDRQE;
1436 		enable_irq(s->irqs[SCIx_RXI_IRQ]);
1437 	}
1438 	serial_port_out(port, SCSCR, scr | SCSCR_RIE);
1439 
1440 	spin_unlock_irqrestore(&port->lock, flags);
1441 }
1442 
1443 static struct dma_chan *sci_request_dma_chan(struct uart_port *port,
1444 					     enum dma_transfer_direction dir)
1445 {
1446 	struct dma_chan *chan;
1447 	struct dma_slave_config cfg;
1448 	int ret;
1449 
1450 	chan = dma_request_slave_channel(port->dev,
1451 					 dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1452 	if (!chan) {
1453 		dev_warn(port->dev, "dma_request_slave_channel failed\n");
1454 		return NULL;
1455 	}
1456 
1457 	memset(&cfg, 0, sizeof(cfg));
1458 	cfg.direction = dir;
1459 	if (dir == DMA_MEM_TO_DEV) {
1460 		cfg.dst_addr = port->mapbase +
1461 			(sci_getreg(port, SCxTDR)->offset << port->regshift);
1462 		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1463 	} else {
1464 		cfg.src_addr = port->mapbase +
1465 			(sci_getreg(port, SCxRDR)->offset << port->regshift);
1466 		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1467 	}
1468 
1469 	ret = dmaengine_slave_config(chan, &cfg);
1470 	if (ret) {
1471 		dev_warn(port->dev, "dmaengine_slave_config failed %d\n", ret);
1472 		dma_release_channel(chan);
1473 		return NULL;
1474 	}
1475 
1476 	return chan;
1477 }
1478 
1479 static void sci_request_dma(struct uart_port *port)
1480 {
1481 	struct sci_port *s = to_sci_port(port);
1482 	struct dma_chan *chan;
1483 
1484 	dev_dbg(port->dev, "%s: port %d\n", __func__, port->line);
1485 
1486 	if (!port->dev->of_node)
1487 		return;
1488 
1489 	s->cookie_tx = -EINVAL;
1490 	chan = sci_request_dma_chan(port, DMA_MEM_TO_DEV);
1491 	dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
1492 	if (chan) {
1493 		s->chan_tx = chan;
1494 		/* UART circular tx buffer is an aligned page. */
1495 		s->tx_dma_addr = dma_map_single(chan->device->dev,
1496 						port->state->xmit.buf,
1497 						UART_XMIT_SIZE,
1498 						DMA_TO_DEVICE);
1499 		if (dma_mapping_error(chan->device->dev, s->tx_dma_addr)) {
1500 			dev_warn(port->dev, "Failed mapping Tx DMA descriptor\n");
1501 			dma_release_channel(chan);
1502 			s->chan_tx = NULL;
1503 		} else {
1504 			dev_dbg(port->dev, "%s: mapped %lu@%p to %pad\n",
1505 				__func__, UART_XMIT_SIZE,
1506 				port->state->xmit.buf, &s->tx_dma_addr);
1507 		}
1508 
1509 		INIT_WORK(&s->work_tx, work_fn_tx);
1510 	}
1511 
1512 	chan = sci_request_dma_chan(port, DMA_DEV_TO_MEM);
1513 	dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
1514 	if (chan) {
1515 		unsigned int i;
1516 		dma_addr_t dma;
1517 		void *buf;
1518 
1519 		s->chan_rx = chan;
1520 
1521 		s->buf_len_rx = 2 * max_t(size_t, 16, port->fifosize);
1522 		buf = dma_alloc_coherent(chan->device->dev, s->buf_len_rx * 2,
1523 					 &dma, GFP_KERNEL);
1524 		if (!buf) {
1525 			dev_warn(port->dev,
1526 				 "Failed to allocate Rx dma buffer, using PIO\n");
1527 			dma_release_channel(chan);
1528 			s->chan_rx = NULL;
1529 			return;
1530 		}
1531 
1532 		for (i = 0; i < 2; i++) {
1533 			struct scatterlist *sg = &s->sg_rx[i];
1534 
1535 			sg_init_table(sg, 1);
1536 			s->rx_buf[i] = buf;
1537 			sg_dma_address(sg) = dma;
1538 			sg_dma_len(sg) = s->buf_len_rx;
1539 
1540 			buf += s->buf_len_rx;
1541 			dma += s->buf_len_rx;
1542 		}
1543 
1544 		setup_timer(&s->rx_timer, rx_timer_fn, (unsigned long)s);
1545 
1546 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1547 			sci_submit_rx(s);
1548 	}
1549 }
1550 
1551 static void sci_free_dma(struct uart_port *port)
1552 {
1553 	struct sci_port *s = to_sci_port(port);
1554 
1555 	if (s->chan_tx)
1556 		sci_tx_dma_release(s, false);
1557 	if (s->chan_rx)
1558 		sci_rx_dma_release(s, false);
1559 }
1560 
1561 static void sci_flush_buffer(struct uart_port *port)
1562 {
1563 	/*
1564 	 * In uart_flush_buffer(), the xmit circular buffer has just been
1565 	 * cleared, so we have to reset tx_dma_len accordingly.
1566 	 */
1567 	to_sci_port(port)->tx_dma_len = 0;
1568 }
1569 #else /* !CONFIG_SERIAL_SH_SCI_DMA */
1570 static inline void sci_request_dma(struct uart_port *port)
1571 {
1572 }
1573 
1574 static inline void sci_free_dma(struct uart_port *port)
1575 {
1576 }
1577 
1578 #define sci_flush_buffer	NULL
1579 #endif /* !CONFIG_SERIAL_SH_SCI_DMA */
1580 
1581 static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
1582 {
1583 	struct uart_port *port = ptr;
1584 	struct sci_port *s = to_sci_port(port);
1585 
1586 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1587 	if (s->chan_rx) {
1588 		u16 scr = serial_port_in(port, SCSCR);
1589 		u16 ssr = serial_port_in(port, SCxSR);
1590 
1591 		/* Disable future Rx interrupts */
1592 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1593 			disable_irq_nosync(irq);
1594 			scr |= SCSCR_RDRQE;
1595 		} else {
1596 			scr &= ~SCSCR_RIE;
1597 			sci_submit_rx(s);
1598 		}
1599 		serial_port_out(port, SCSCR, scr);
1600 		/* Clear current interrupt */
1601 		serial_port_out(port, SCxSR,
1602 				ssr & ~(SCIF_DR | SCxSR_RDxF(port)));
1603 		dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u jiffies\n",
1604 			jiffies, s->rx_timeout);
1605 		mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
1606 
1607 		return IRQ_HANDLED;
1608 	}
1609 #endif
1610 
1611 	if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0) {
1612 		if (!scif_rtrg_enabled(port))
1613 			scif_set_rtrg(port, s->rx_trigger);
1614 
1615 		mod_timer(&s->rx_fifo_timer, jiffies + DIV_ROUND_UP(
1616 			  s->rx_frame * s->rx_fifo_timeout, 1000));
1617 	}
1618 
1619 	/* I think sci_receive_chars has to be called irrespective
1620 	 * of whether the I_IXOFF is set, otherwise, how is the interrupt
1621 	 * to be disabled?
1622 	 */
1623 	sci_receive_chars(ptr);
1624 
1625 	return IRQ_HANDLED;
1626 }
1627 
1628 static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
1629 {
1630 	struct uart_port *port = ptr;
1631 	unsigned long flags;
1632 
1633 	spin_lock_irqsave(&port->lock, flags);
1634 	sci_transmit_chars(port);
1635 	spin_unlock_irqrestore(&port->lock, flags);
1636 
1637 	return IRQ_HANDLED;
1638 }
1639 
1640 static irqreturn_t sci_er_interrupt(int irq, void *ptr)
1641 {
1642 	struct uart_port *port = ptr;
1643 	struct sci_port *s = to_sci_port(port);
1644 
1645 	/* Handle errors */
1646 	if (port->type == PORT_SCI) {
1647 		if (sci_handle_errors(port)) {
1648 			/* discard character in rx buffer */
1649 			serial_port_in(port, SCxSR);
1650 			sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
1651 		}
1652 	} else {
1653 		sci_handle_fifo_overrun(port);
1654 		if (!s->chan_rx)
1655 			sci_receive_chars(ptr);
1656 	}
1657 
1658 	sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
1659 
1660 	/* Kick the transmission */
1661 	if (!s->chan_tx)
1662 		sci_tx_interrupt(irq, ptr);
1663 
1664 	return IRQ_HANDLED;
1665 }
1666 
1667 static irqreturn_t sci_br_interrupt(int irq, void *ptr)
1668 {
1669 	struct uart_port *port = ptr;
1670 
1671 	/* Handle BREAKs */
1672 	sci_handle_breaks(port);
1673 	sci_clear_SCxSR(port, SCxSR_BREAK_CLEAR(port));
1674 
1675 	return IRQ_HANDLED;
1676 }
1677 
1678 static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
1679 {
1680 	unsigned short ssr_status, scr_status, err_enabled, orer_status = 0;
1681 	struct uart_port *port = ptr;
1682 	struct sci_port *s = to_sci_port(port);
1683 	irqreturn_t ret = IRQ_NONE;
1684 
1685 	ssr_status = serial_port_in(port, SCxSR);
1686 	scr_status = serial_port_in(port, SCSCR);
1687 	if (s->params->overrun_reg == SCxSR)
1688 		orer_status = ssr_status;
1689 	else if (sci_getreg(port, s->params->overrun_reg)->size)
1690 		orer_status = serial_port_in(port, s->params->overrun_reg);
1691 
1692 	err_enabled = scr_status & port_rx_irq_mask(port);
1693 
1694 	/* Tx Interrupt */
1695 	if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) &&
1696 	    !s->chan_tx)
1697 		ret = sci_tx_interrupt(irq, ptr);
1698 
1699 	/*
1700 	 * Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
1701 	 * DR flags
1702 	 */
1703 	if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
1704 	    (scr_status & SCSCR_RIE))
1705 		ret = sci_rx_interrupt(irq, ptr);
1706 
1707 	/* Error Interrupt */
1708 	if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
1709 		ret = sci_er_interrupt(irq, ptr);
1710 
1711 	/* Break Interrupt */
1712 	if ((ssr_status & SCxSR_BRK(port)) && err_enabled)
1713 		ret = sci_br_interrupt(irq, ptr);
1714 
1715 	/* Overrun Interrupt */
1716 	if (orer_status & s->params->overrun_mask) {
1717 		sci_handle_fifo_overrun(port);
1718 		ret = IRQ_HANDLED;
1719 	}
1720 
1721 	return ret;
1722 }
1723 
1724 static const struct sci_irq_desc {
1725 	const char	*desc;
1726 	irq_handler_t	handler;
1727 } sci_irq_desc[] = {
1728 	/*
1729 	 * Split out handlers, the default case.
1730 	 */
1731 	[SCIx_ERI_IRQ] = {
1732 		.desc = "rx err",
1733 		.handler = sci_er_interrupt,
1734 	},
1735 
1736 	[SCIx_RXI_IRQ] = {
1737 		.desc = "rx full",
1738 		.handler = sci_rx_interrupt,
1739 	},
1740 
1741 	[SCIx_TXI_IRQ] = {
1742 		.desc = "tx empty",
1743 		.handler = sci_tx_interrupt,
1744 	},
1745 
1746 	[SCIx_BRI_IRQ] = {
1747 		.desc = "break",
1748 		.handler = sci_br_interrupt,
1749 	},
1750 
1751 	/*
1752 	 * Special muxed handler.
1753 	 */
1754 	[SCIx_MUX_IRQ] = {
1755 		.desc = "mux",
1756 		.handler = sci_mpxed_interrupt,
1757 	},
1758 };
1759 
1760 static int sci_request_irq(struct sci_port *port)
1761 {
1762 	struct uart_port *up = &port->port;
1763 	int i, j, ret = 0;
1764 
1765 	for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) {
1766 		const struct sci_irq_desc *desc;
1767 		int irq;
1768 
1769 		if (SCIx_IRQ_IS_MUXED(port)) {
1770 			i = SCIx_MUX_IRQ;
1771 			irq = up->irq;
1772 		} else {
1773 			irq = port->irqs[i];
1774 
1775 			/*
1776 			 * Certain port types won't support all of the
1777 			 * available interrupt sources.
1778 			 */
1779 			if (unlikely(irq < 0))
1780 				continue;
1781 		}
1782 
1783 		desc = sci_irq_desc + i;
1784 		port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s",
1785 					    dev_name(up->dev), desc->desc);
1786 		if (!port->irqstr[j]) {
1787 			ret = -ENOMEM;
1788 			goto out_nomem;
1789 		}
1790 
1791 		ret = request_irq(irq, desc->handler, up->irqflags,
1792 				  port->irqstr[j], port);
1793 		if (unlikely(ret)) {
1794 			dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc);
1795 			goto out_noirq;
1796 		}
1797 	}
1798 
1799 	return 0;
1800 
1801 out_noirq:
1802 	while (--i >= 0)
1803 		free_irq(port->irqs[i], port);
1804 
1805 out_nomem:
1806 	while (--j >= 0)
1807 		kfree(port->irqstr[j]);
1808 
1809 	return ret;
1810 }
1811 
1812 static void sci_free_irq(struct sci_port *port)
1813 {
1814 	int i;
1815 
1816 	/*
1817 	 * Intentionally in reverse order so we iterate over the muxed
1818 	 * IRQ first.
1819 	 */
1820 	for (i = 0; i < SCIx_NR_IRQS; i++) {
1821 		int irq = port->irqs[i];
1822 
1823 		/*
1824 		 * Certain port types won't support all of the available
1825 		 * interrupt sources.
1826 		 */
1827 		if (unlikely(irq < 0))
1828 			continue;
1829 
1830 		free_irq(port->irqs[i], port);
1831 		kfree(port->irqstr[i]);
1832 
1833 		if (SCIx_IRQ_IS_MUXED(port)) {
1834 			/* If there's only one IRQ, we're done. */
1835 			return;
1836 		}
1837 	}
1838 }
1839 
1840 static unsigned int sci_tx_empty(struct uart_port *port)
1841 {
1842 	unsigned short status = serial_port_in(port, SCxSR);
1843 	unsigned short in_tx_fifo = sci_txfill(port);
1844 
1845 	return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
1846 }
1847 
1848 static void sci_set_rts(struct uart_port *port, bool state)
1849 {
1850 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1851 		u16 data = serial_port_in(port, SCPDR);
1852 
1853 		/* Active low */
1854 		if (state)
1855 			data &= ~SCPDR_RTSD;
1856 		else
1857 			data |= SCPDR_RTSD;
1858 		serial_port_out(port, SCPDR, data);
1859 
1860 		/* RTS# is output */
1861 		serial_port_out(port, SCPCR,
1862 				serial_port_in(port, SCPCR) | SCPCR_RTSC);
1863 	} else if (sci_getreg(port, SCSPTR)->size) {
1864 		u16 ctrl = serial_port_in(port, SCSPTR);
1865 
1866 		/* Active low */
1867 		if (state)
1868 			ctrl &= ~SCSPTR_RTSDT;
1869 		else
1870 			ctrl |= SCSPTR_RTSDT;
1871 		serial_port_out(port, SCSPTR, ctrl);
1872 	}
1873 }
1874 
1875 static bool sci_get_cts(struct uart_port *port)
1876 {
1877 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1878 		/* Active low */
1879 		return !(serial_port_in(port, SCPDR) & SCPDR_CTSD);
1880 	} else if (sci_getreg(port, SCSPTR)->size) {
1881 		/* Active low */
1882 		return !(serial_port_in(port, SCSPTR) & SCSPTR_CTSDT);
1883 	}
1884 
1885 	return true;
1886 }
1887 
1888 /*
1889  * Modem control is a bit of a mixed bag for SCI(F) ports. Generally
1890  * CTS/RTS is supported in hardware by at least one port and controlled
1891  * via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently
1892  * handled via the ->init_pins() op, which is a bit of a one-way street,
1893  * lacking any ability to defer pin control -- this will later be
1894  * converted over to the GPIO framework).
1895  *
1896  * Other modes (such as loopback) are supported generically on certain
1897  * port types, but not others. For these it's sufficient to test for the
1898  * existence of the support register and simply ignore the port type.
1899  */
1900 static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
1901 {
1902 	struct sci_port *s = to_sci_port(port);
1903 
1904 	if (mctrl & TIOCM_LOOP) {
1905 		const struct plat_sci_reg *reg;
1906 
1907 		/*
1908 		 * Standard loopback mode for SCFCR ports.
1909 		 */
1910 		reg = sci_getreg(port, SCFCR);
1911 		if (reg->size)
1912 			serial_port_out(port, SCFCR,
1913 					serial_port_in(port, SCFCR) |
1914 					SCFCR_LOOP);
1915 	}
1916 
1917 	mctrl_gpio_set(s->gpios, mctrl);
1918 
1919 	if (!s->has_rtscts)
1920 		return;
1921 
1922 	if (!(mctrl & TIOCM_RTS)) {
1923 		/* Disable Auto RTS */
1924 		serial_port_out(port, SCFCR,
1925 				serial_port_in(port, SCFCR) & ~SCFCR_MCE);
1926 
1927 		/* Clear RTS */
1928 		sci_set_rts(port, 0);
1929 	} else if (s->autorts) {
1930 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1931 			/* Enable RTS# pin function */
1932 			serial_port_out(port, SCPCR,
1933 				serial_port_in(port, SCPCR) & ~SCPCR_RTSC);
1934 		}
1935 
1936 		/* Enable Auto RTS */
1937 		serial_port_out(port, SCFCR,
1938 				serial_port_in(port, SCFCR) | SCFCR_MCE);
1939 	} else {
1940 		/* Set RTS */
1941 		sci_set_rts(port, 1);
1942 	}
1943 }
1944 
1945 static unsigned int sci_get_mctrl(struct uart_port *port)
1946 {
1947 	struct sci_port *s = to_sci_port(port);
1948 	struct mctrl_gpios *gpios = s->gpios;
1949 	unsigned int mctrl = 0;
1950 
1951 	mctrl_gpio_get(gpios, &mctrl);
1952 
1953 	/*
1954 	 * CTS/RTS is handled in hardware when supported, while nothing
1955 	 * else is wired up.
1956 	 */
1957 	if (s->autorts) {
1958 		if (sci_get_cts(port))
1959 			mctrl |= TIOCM_CTS;
1960 	} else if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_CTS))) {
1961 		mctrl |= TIOCM_CTS;
1962 	}
1963 	if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_DSR)))
1964 		mctrl |= TIOCM_DSR;
1965 	if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_DCD)))
1966 		mctrl |= TIOCM_CAR;
1967 
1968 	return mctrl;
1969 }
1970 
1971 static void sci_enable_ms(struct uart_port *port)
1972 {
1973 	mctrl_gpio_enable_ms(to_sci_port(port)->gpios);
1974 }
1975 
1976 static void sci_break_ctl(struct uart_port *port, int break_state)
1977 {
1978 	unsigned short scscr, scsptr;
1979 
1980 	/* check wheter the port has SCSPTR */
1981 	if (!sci_getreg(port, SCSPTR)->size) {
1982 		/*
1983 		 * Not supported by hardware. Most parts couple break and rx
1984 		 * interrupts together, with break detection always enabled.
1985 		 */
1986 		return;
1987 	}
1988 
1989 	scsptr = serial_port_in(port, SCSPTR);
1990 	scscr = serial_port_in(port, SCSCR);
1991 
1992 	if (break_state == -1) {
1993 		scsptr = (scsptr | SCSPTR_SPB2IO) & ~SCSPTR_SPB2DT;
1994 		scscr &= ~SCSCR_TE;
1995 	} else {
1996 		scsptr = (scsptr | SCSPTR_SPB2DT) & ~SCSPTR_SPB2IO;
1997 		scscr |= SCSCR_TE;
1998 	}
1999 
2000 	serial_port_out(port, SCSPTR, scsptr);
2001 	serial_port_out(port, SCSCR, scscr);
2002 }
2003 
2004 static int sci_startup(struct uart_port *port)
2005 {
2006 	struct sci_port *s = to_sci_port(port);
2007 	int ret;
2008 
2009 	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2010 
2011 	sci_request_dma(port);
2012 
2013 	ret = sci_request_irq(s);
2014 	if (unlikely(ret < 0)) {
2015 		sci_free_dma(port);
2016 		return ret;
2017 	}
2018 
2019 	return 0;
2020 }
2021 
2022 static void sci_shutdown(struct uart_port *port)
2023 {
2024 	struct sci_port *s = to_sci_port(port);
2025 	unsigned long flags;
2026 	u16 scr;
2027 
2028 	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2029 
2030 	s->autorts = false;
2031 	mctrl_gpio_disable_ms(to_sci_port(port)->gpios);
2032 
2033 	spin_lock_irqsave(&port->lock, flags);
2034 	sci_stop_rx(port);
2035 	sci_stop_tx(port);
2036 	/* Stop RX and TX, disable related interrupts, keep clock source */
2037 	scr = serial_port_in(port, SCSCR);
2038 	serial_port_out(port, SCSCR, scr & (SCSCR_CKE1 | SCSCR_CKE0));
2039 	spin_unlock_irqrestore(&port->lock, flags);
2040 
2041 #ifdef CONFIG_SERIAL_SH_SCI_DMA
2042 	if (s->chan_rx) {
2043 		dev_dbg(port->dev, "%s(%d) deleting rx_timer\n", __func__,
2044 			port->line);
2045 		del_timer_sync(&s->rx_timer);
2046 	}
2047 #endif
2048 
2049 	sci_free_irq(s);
2050 	sci_free_dma(port);
2051 }
2052 
2053 static int sci_sck_calc(struct sci_port *s, unsigned int bps,
2054 			unsigned int *srr)
2055 {
2056 	unsigned long freq = s->clk_rates[SCI_SCK];
2057 	int err, min_err = INT_MAX;
2058 	unsigned int sr;
2059 
2060 	if (s->port.type != PORT_HSCIF)
2061 		freq *= 2;
2062 
2063 	for_each_sr(sr, s) {
2064 		err = DIV_ROUND_CLOSEST(freq, sr) - bps;
2065 		if (abs(err) >= abs(min_err))
2066 			continue;
2067 
2068 		min_err = err;
2069 		*srr = sr - 1;
2070 
2071 		if (!err)
2072 			break;
2073 	}
2074 
2075 	dev_dbg(s->port.dev, "SCK: %u%+d bps using SR %u\n", bps, min_err,
2076 		*srr + 1);
2077 	return min_err;
2078 }
2079 
2080 static int sci_brg_calc(struct sci_port *s, unsigned int bps,
2081 			unsigned long freq, unsigned int *dlr,
2082 			unsigned int *srr)
2083 {
2084 	int err, min_err = INT_MAX;
2085 	unsigned int sr, dl;
2086 
2087 	if (s->port.type != PORT_HSCIF)
2088 		freq *= 2;
2089 
2090 	for_each_sr(sr, s) {
2091 		dl = DIV_ROUND_CLOSEST(freq, sr * bps);
2092 		dl = clamp(dl, 1U, 65535U);
2093 
2094 		err = DIV_ROUND_CLOSEST(freq, sr * dl) - bps;
2095 		if (abs(err) >= abs(min_err))
2096 			continue;
2097 
2098 		min_err = err;
2099 		*dlr = dl;
2100 		*srr = sr - 1;
2101 
2102 		if (!err)
2103 			break;
2104 	}
2105 
2106 	dev_dbg(s->port.dev, "BRG: %u%+d bps using DL %u SR %u\n", bps,
2107 		min_err, *dlr, *srr + 1);
2108 	return min_err;
2109 }
2110 
2111 /* calculate sample rate, BRR, and clock select */
2112 static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
2113 			  unsigned int *brr, unsigned int *srr,
2114 			  unsigned int *cks)
2115 {
2116 	unsigned long freq = s->clk_rates[SCI_FCK];
2117 	unsigned int sr, br, prediv, scrate, c;
2118 	int err, min_err = INT_MAX;
2119 
2120 	if (s->port.type != PORT_HSCIF)
2121 		freq *= 2;
2122 
2123 	/*
2124 	 * Find the combination of sample rate and clock select with the
2125 	 * smallest deviation from the desired baud rate.
2126 	 * Prefer high sample rates to maximise the receive margin.
2127 	 *
2128 	 * M: Receive margin (%)
2129 	 * N: Ratio of bit rate to clock (N = sampling rate)
2130 	 * D: Clock duty (D = 0 to 1.0)
2131 	 * L: Frame length (L = 9 to 12)
2132 	 * F: Absolute value of clock frequency deviation
2133 	 *
2134 	 *  M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) -
2135 	 *      (|D - 0.5| / N * (1 + F))|
2136 	 *  NOTE: Usually, treat D for 0.5, F is 0 by this calculation.
2137 	 */
2138 	for_each_sr(sr, s) {
2139 		for (c = 0; c <= 3; c++) {
2140 			/* integerized formulas from HSCIF documentation */
2141 			prediv = sr * (1 << (2 * c + 1));
2142 
2143 			/*
2144 			 * We need to calculate:
2145 			 *
2146 			 *     br = freq / (prediv * bps) clamped to [1..256]
2147 			 *     err = freq / (br * prediv) - bps
2148 			 *
2149 			 * Watch out for overflow when calculating the desired
2150 			 * sampling clock rate!
2151 			 */
2152 			if (bps > UINT_MAX / prediv)
2153 				break;
2154 
2155 			scrate = prediv * bps;
2156 			br = DIV_ROUND_CLOSEST(freq, scrate);
2157 			br = clamp(br, 1U, 256U);
2158 
2159 			err = DIV_ROUND_CLOSEST(freq, br * prediv) - bps;
2160 			if (abs(err) >= abs(min_err))
2161 				continue;
2162 
2163 			min_err = err;
2164 			*brr = br - 1;
2165 			*srr = sr - 1;
2166 			*cks = c;
2167 
2168 			if (!err)
2169 				goto found;
2170 		}
2171 	}
2172 
2173 found:
2174 	dev_dbg(s->port.dev, "BRR: %u%+d bps using N %u SR %u cks %u\n", bps,
2175 		min_err, *brr, *srr + 1, *cks);
2176 	return min_err;
2177 }
2178 
2179 static void sci_reset(struct uart_port *port)
2180 {
2181 	const struct plat_sci_reg *reg;
2182 	unsigned int status;
2183 	struct sci_port *s = to_sci_port(port);
2184 
2185 	serial_port_out(port, SCSCR, 0x00);	/* TE=0, RE=0, CKE1=0 */
2186 
2187 	reg = sci_getreg(port, SCFCR);
2188 	if (reg->size)
2189 		serial_port_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
2190 
2191 	sci_clear_SCxSR(port,
2192 			SCxSR_RDxF_CLEAR(port) & SCxSR_ERROR_CLEAR(port) &
2193 			SCxSR_BREAK_CLEAR(port));
2194 	if (sci_getreg(port, SCLSR)->size) {
2195 		status = serial_port_in(port, SCLSR);
2196 		status &= ~(SCLSR_TO | SCLSR_ORER);
2197 		serial_port_out(port, SCLSR, status);
2198 	}
2199 
2200 	if (s->rx_trigger > 1) {
2201 		if (s->rx_fifo_timeout) {
2202 			scif_set_rtrg(port, 1);
2203 			setup_timer(&s->rx_fifo_timer, rx_fifo_timer_fn,
2204 				    (unsigned long)s);
2205 		} else {
2206 			if (port->type == PORT_SCIFA ||
2207 			    port->type == PORT_SCIFB)
2208 				scif_set_rtrg(port, 1);
2209 			else
2210 				scif_set_rtrg(port, s->rx_trigger);
2211 		}
2212 	}
2213 }
2214 
2215 static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
2216 			    struct ktermios *old)
2217 {
2218 	unsigned int baud, smr_val = SCSMR_ASYNC, scr_val = 0, i, bits;
2219 	unsigned int brr = 255, cks = 0, srr = 15, dl = 0, sccks = 0;
2220 	unsigned int brr1 = 255, cks1 = 0, srr1 = 15, dl1 = 0;
2221 	struct sci_port *s = to_sci_port(port);
2222 	const struct plat_sci_reg *reg;
2223 	int min_err = INT_MAX, err;
2224 	unsigned long max_freq = 0;
2225 	int best_clk = -1;
2226 
2227 	if ((termios->c_cflag & CSIZE) == CS7)
2228 		smr_val |= SCSMR_CHR;
2229 	if (termios->c_cflag & PARENB)
2230 		smr_val |= SCSMR_PE;
2231 	if (termios->c_cflag & PARODD)
2232 		smr_val |= SCSMR_PE | SCSMR_ODD;
2233 	if (termios->c_cflag & CSTOPB)
2234 		smr_val |= SCSMR_STOP;
2235 
2236 	/*
2237 	 * earlyprintk comes here early on with port->uartclk set to zero.
2238 	 * the clock framework is not up and running at this point so here
2239 	 * we assume that 115200 is the maximum baud rate. please note that
2240 	 * the baud rate is not programmed during earlyprintk - it is assumed
2241 	 * that the previous boot loader has enabled required clocks and
2242 	 * setup the baud rate generator hardware for us already.
2243 	 */
2244 	if (!port->uartclk) {
2245 		baud = uart_get_baud_rate(port, termios, old, 0, 115200);
2246 		goto done;
2247 	}
2248 
2249 	for (i = 0; i < SCI_NUM_CLKS; i++)
2250 		max_freq = max(max_freq, s->clk_rates[i]);
2251 
2252 	baud = uart_get_baud_rate(port, termios, old, 0, max_freq / min_sr(s));
2253 	if (!baud)
2254 		goto done;
2255 
2256 	/*
2257 	 * There can be multiple sources for the sampling clock.  Find the one
2258 	 * that gives us the smallest deviation from the desired baud rate.
2259 	 */
2260 
2261 	/* Optional Undivided External Clock */
2262 	if (s->clk_rates[SCI_SCK] && port->type != PORT_SCIFA &&
2263 	    port->type != PORT_SCIFB) {
2264 		err = sci_sck_calc(s, baud, &srr1);
2265 		if (abs(err) < abs(min_err)) {
2266 			best_clk = SCI_SCK;
2267 			scr_val = SCSCR_CKE1;
2268 			sccks = SCCKS_CKS;
2269 			min_err = err;
2270 			srr = srr1;
2271 			if (!err)
2272 				goto done;
2273 		}
2274 	}
2275 
2276 	/* Optional BRG Frequency Divided External Clock */
2277 	if (s->clk_rates[SCI_SCIF_CLK] && sci_getreg(port, SCDL)->size) {
2278 		err = sci_brg_calc(s, baud, s->clk_rates[SCI_SCIF_CLK], &dl1,
2279 				   &srr1);
2280 		if (abs(err) < abs(min_err)) {
2281 			best_clk = SCI_SCIF_CLK;
2282 			scr_val = SCSCR_CKE1;
2283 			sccks = 0;
2284 			min_err = err;
2285 			dl = dl1;
2286 			srr = srr1;
2287 			if (!err)
2288 				goto done;
2289 		}
2290 	}
2291 
2292 	/* Optional BRG Frequency Divided Internal Clock */
2293 	if (s->clk_rates[SCI_BRG_INT] && sci_getreg(port, SCDL)->size) {
2294 		err = sci_brg_calc(s, baud, s->clk_rates[SCI_BRG_INT], &dl1,
2295 				   &srr1);
2296 		if (abs(err) < abs(min_err)) {
2297 			best_clk = SCI_BRG_INT;
2298 			scr_val = SCSCR_CKE1;
2299 			sccks = SCCKS_XIN;
2300 			min_err = err;
2301 			dl = dl1;
2302 			srr = srr1;
2303 			if (!min_err)
2304 				goto done;
2305 		}
2306 	}
2307 
2308 	/* Divided Functional Clock using standard Bit Rate Register */
2309 	err = sci_scbrr_calc(s, baud, &brr1, &srr1, &cks1);
2310 	if (abs(err) < abs(min_err)) {
2311 		best_clk = SCI_FCK;
2312 		scr_val = 0;
2313 		min_err = err;
2314 		brr = brr1;
2315 		srr = srr1;
2316 		cks = cks1;
2317 	}
2318 
2319 done:
2320 	if (best_clk >= 0)
2321 		dev_dbg(port->dev, "Using clk %pC for %u%+d bps\n",
2322 			s->clks[best_clk], baud, min_err);
2323 
2324 	sci_port_enable(s);
2325 
2326 	/*
2327 	 * Program the optional External Baud Rate Generator (BRG) first.
2328 	 * It controls the mux to select (H)SCK or frequency divided clock.
2329 	 */
2330 	if (best_clk >= 0 && sci_getreg(port, SCCKS)->size) {
2331 		serial_port_out(port, SCDL, dl);
2332 		serial_port_out(port, SCCKS, sccks);
2333 	}
2334 
2335 	sci_reset(port);
2336 
2337 	uart_update_timeout(port, termios->c_cflag, baud);
2338 
2339 	if (best_clk >= 0) {
2340 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
2341 			switch (srr + 1) {
2342 			case 5:  smr_val |= SCSMR_SRC_5;  break;
2343 			case 7:  smr_val |= SCSMR_SRC_7;  break;
2344 			case 11: smr_val |= SCSMR_SRC_11; break;
2345 			case 13: smr_val |= SCSMR_SRC_13; break;
2346 			case 16: smr_val |= SCSMR_SRC_16; break;
2347 			case 17: smr_val |= SCSMR_SRC_17; break;
2348 			case 19: smr_val |= SCSMR_SRC_19; break;
2349 			case 27: smr_val |= SCSMR_SRC_27; break;
2350 			}
2351 		smr_val |= cks;
2352 		dev_dbg(port->dev,
2353 			 "SCR 0x%x SMR 0x%x BRR %u CKS 0x%x DL %u SRR %u\n",
2354 			 scr_val, smr_val, brr, sccks, dl, srr);
2355 		serial_port_out(port, SCSCR, scr_val);
2356 		serial_port_out(port, SCSMR, smr_val);
2357 		serial_port_out(port, SCBRR, brr);
2358 		if (sci_getreg(port, HSSRR)->size)
2359 			serial_port_out(port, HSSRR, srr | HSCIF_SRE);
2360 
2361 		/* Wait one bit interval */
2362 		udelay((1000000 + (baud - 1)) / baud);
2363 	} else {
2364 		/* Don't touch the bit rate configuration */
2365 		scr_val = s->cfg->scscr & (SCSCR_CKE1 | SCSCR_CKE0);
2366 		smr_val |= serial_port_in(port, SCSMR) &
2367 			   (SCSMR_CKEDG | SCSMR_SRC_MASK | SCSMR_CKS);
2368 		dev_dbg(port->dev, "SCR 0x%x SMR 0x%x\n", scr_val, smr_val);
2369 		serial_port_out(port, SCSCR, scr_val);
2370 		serial_port_out(port, SCSMR, smr_val);
2371 	}
2372 
2373 	sci_init_pins(port, termios->c_cflag);
2374 
2375 	port->status &= ~UPSTAT_AUTOCTS;
2376 	s->autorts = false;
2377 	reg = sci_getreg(port, SCFCR);
2378 	if (reg->size) {
2379 		unsigned short ctrl = serial_port_in(port, SCFCR);
2380 
2381 		if ((port->flags & UPF_HARD_FLOW) &&
2382 		    (termios->c_cflag & CRTSCTS)) {
2383 			/* There is no CTS interrupt to restart the hardware */
2384 			port->status |= UPSTAT_AUTOCTS;
2385 			/* MCE is enabled when RTS is raised */
2386 			s->autorts = true;
2387 		}
2388 
2389 		/*
2390 		 * As we've done a sci_reset() above, ensure we don't
2391 		 * interfere with the FIFOs while toggling MCE. As the
2392 		 * reset values could still be set, simply mask them out.
2393 		 */
2394 		ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST);
2395 
2396 		serial_port_out(port, SCFCR, ctrl);
2397 	}
2398 	if (port->flags & UPF_HARD_FLOW) {
2399 		/* Refresh (Auto) RTS */
2400 		sci_set_mctrl(port, port->mctrl);
2401 	}
2402 
2403 	scr_val |= SCSCR_RE | SCSCR_TE |
2404 		   (s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0));
2405 	dev_dbg(port->dev, "SCSCR 0x%x\n", scr_val);
2406 	serial_port_out(port, SCSCR, scr_val);
2407 	if ((srr + 1 == 5) &&
2408 	    (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) {
2409 		/*
2410 		 * In asynchronous mode, when the sampling rate is 1/5, first
2411 		 * received data may become invalid on some SCIFA and SCIFB.
2412 		 * To avoid this problem wait more than 1 serial data time (1
2413 		 * bit time x serial data number) after setting SCSCR.RE = 1.
2414 		 */
2415 		udelay(DIV_ROUND_UP(10 * 1000000, baud));
2416 	}
2417 
2418 	/*
2419 	 * Calculate delay for 2 DMA buffers (4 FIFO).
2420 	 * See serial_core.c::uart_update_timeout().
2421 	 * With 10 bits (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above
2422 	 * function calculates 1 jiffie for the data plus 5 jiffies for the
2423 	 * "slop(e)." Then below we calculate 5 jiffies (20ms) for 2 DMA
2424 	 * buffers (4 FIFO sizes), but when performing a faster transfer, the
2425 	 * value obtained by this formula is too small. Therefore, if the value
2426 	 * is smaller than 20ms, use 20ms as the timeout value for DMA.
2427 	 */
2428 	/* byte size and parity */
2429 	switch (termios->c_cflag & CSIZE) {
2430 	case CS5:
2431 		bits = 7;
2432 		break;
2433 	case CS6:
2434 		bits = 8;
2435 		break;
2436 	case CS7:
2437 		bits = 9;
2438 		break;
2439 	default:
2440 		bits = 10;
2441 		break;
2442 	}
2443 
2444 	if (termios->c_cflag & CSTOPB)
2445 		bits++;
2446 	if (termios->c_cflag & PARENB)
2447 		bits++;
2448 
2449 	s->rx_frame = (100 * bits * HZ) / (baud / 10);
2450 #ifdef CONFIG_SERIAL_SH_SCI_DMA
2451 	s->rx_timeout = DIV_ROUND_UP(s->buf_len_rx * 2 * s->rx_frame, 1000);
2452 	dev_dbg(port->dev, "DMA Rx t-out %ums, tty t-out %u jiffies\n",
2453 		s->rx_timeout * 1000 / HZ, port->timeout);
2454 	if (s->rx_timeout < msecs_to_jiffies(20))
2455 		s->rx_timeout = msecs_to_jiffies(20);
2456 #endif
2457 
2458 	if ((termios->c_cflag & CREAD) != 0)
2459 		sci_start_rx(port);
2460 
2461 	sci_port_disable(s);
2462 
2463 	if (UART_ENABLE_MS(port, termios->c_cflag))
2464 		sci_enable_ms(port);
2465 }
2466 
2467 static void sci_pm(struct uart_port *port, unsigned int state,
2468 		   unsigned int oldstate)
2469 {
2470 	struct sci_port *sci_port = to_sci_port(port);
2471 
2472 	switch (state) {
2473 	case UART_PM_STATE_OFF:
2474 		sci_port_disable(sci_port);
2475 		break;
2476 	default:
2477 		sci_port_enable(sci_port);
2478 		break;
2479 	}
2480 }
2481 
2482 static const char *sci_type(struct uart_port *port)
2483 {
2484 	switch (port->type) {
2485 	case PORT_IRDA:
2486 		return "irda";
2487 	case PORT_SCI:
2488 		return "sci";
2489 	case PORT_SCIF:
2490 		return "scif";
2491 	case PORT_SCIFA:
2492 		return "scifa";
2493 	case PORT_SCIFB:
2494 		return "scifb";
2495 	case PORT_HSCIF:
2496 		return "hscif";
2497 	}
2498 
2499 	return NULL;
2500 }
2501 
2502 static int sci_remap_port(struct uart_port *port)
2503 {
2504 	struct sci_port *sport = to_sci_port(port);
2505 
2506 	/*
2507 	 * Nothing to do if there's already an established membase.
2508 	 */
2509 	if (port->membase)
2510 		return 0;
2511 
2512 	if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2513 		port->membase = ioremap_nocache(port->mapbase, sport->reg_size);
2514 		if (unlikely(!port->membase)) {
2515 			dev_err(port->dev, "can't remap port#%d\n", port->line);
2516 			return -ENXIO;
2517 		}
2518 	} else {
2519 		/*
2520 		 * For the simple (and majority of) cases where we don't
2521 		 * need to do any remapping, just cast the cookie
2522 		 * directly.
2523 		 */
2524 		port->membase = (void __iomem *)(uintptr_t)port->mapbase;
2525 	}
2526 
2527 	return 0;
2528 }
2529 
2530 static void sci_release_port(struct uart_port *port)
2531 {
2532 	struct sci_port *sport = to_sci_port(port);
2533 
2534 	if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2535 		iounmap(port->membase);
2536 		port->membase = NULL;
2537 	}
2538 
2539 	release_mem_region(port->mapbase, sport->reg_size);
2540 }
2541 
2542 static int sci_request_port(struct uart_port *port)
2543 {
2544 	struct resource *res;
2545 	struct sci_port *sport = to_sci_port(port);
2546 	int ret;
2547 
2548 	res = request_mem_region(port->mapbase, sport->reg_size,
2549 				 dev_name(port->dev));
2550 	if (unlikely(res == NULL)) {
2551 		dev_err(port->dev, "request_mem_region failed.");
2552 		return -EBUSY;
2553 	}
2554 
2555 	ret = sci_remap_port(port);
2556 	if (unlikely(ret != 0)) {
2557 		release_resource(res);
2558 		return ret;
2559 	}
2560 
2561 	return 0;
2562 }
2563 
2564 static void sci_config_port(struct uart_port *port, int flags)
2565 {
2566 	if (flags & UART_CONFIG_TYPE) {
2567 		struct sci_port *sport = to_sci_port(port);
2568 
2569 		port->type = sport->cfg->type;
2570 		sci_request_port(port);
2571 	}
2572 }
2573 
2574 static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
2575 {
2576 	if (ser->baud_base < 2400)
2577 		/* No paper tape reader for Mitch.. */
2578 		return -EINVAL;
2579 
2580 	return 0;
2581 }
2582 
2583 static const struct uart_ops sci_uart_ops = {
2584 	.tx_empty	= sci_tx_empty,
2585 	.set_mctrl	= sci_set_mctrl,
2586 	.get_mctrl	= sci_get_mctrl,
2587 	.start_tx	= sci_start_tx,
2588 	.stop_tx	= sci_stop_tx,
2589 	.stop_rx	= sci_stop_rx,
2590 	.enable_ms	= sci_enable_ms,
2591 	.break_ctl	= sci_break_ctl,
2592 	.startup	= sci_startup,
2593 	.shutdown	= sci_shutdown,
2594 	.flush_buffer	= sci_flush_buffer,
2595 	.set_termios	= sci_set_termios,
2596 	.pm		= sci_pm,
2597 	.type		= sci_type,
2598 	.release_port	= sci_release_port,
2599 	.request_port	= sci_request_port,
2600 	.config_port	= sci_config_port,
2601 	.verify_port	= sci_verify_port,
2602 #ifdef CONFIG_CONSOLE_POLL
2603 	.poll_get_char	= sci_poll_get_char,
2604 	.poll_put_char	= sci_poll_put_char,
2605 #endif
2606 };
2607 
2608 static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
2609 {
2610 	const char *clk_names[] = {
2611 		[SCI_FCK] = "fck",
2612 		[SCI_SCK] = "sck",
2613 		[SCI_BRG_INT] = "brg_int",
2614 		[SCI_SCIF_CLK] = "scif_clk",
2615 	};
2616 	struct clk *clk;
2617 	unsigned int i;
2618 
2619 	if (sci_port->cfg->type == PORT_HSCIF)
2620 		clk_names[SCI_SCK] = "hsck";
2621 
2622 	for (i = 0; i < SCI_NUM_CLKS; i++) {
2623 		clk = devm_clk_get(dev, clk_names[i]);
2624 		if (PTR_ERR(clk) == -EPROBE_DEFER)
2625 			return -EPROBE_DEFER;
2626 
2627 		if (IS_ERR(clk) && i == SCI_FCK) {
2628 			/*
2629 			 * "fck" used to be called "sci_ick", and we need to
2630 			 * maintain DT backward compatibility.
2631 			 */
2632 			clk = devm_clk_get(dev, "sci_ick");
2633 			if (PTR_ERR(clk) == -EPROBE_DEFER)
2634 				return -EPROBE_DEFER;
2635 
2636 			if (!IS_ERR(clk))
2637 				goto found;
2638 
2639 			/*
2640 			 * Not all SH platforms declare a clock lookup entry
2641 			 * for SCI devices, in which case we need to get the
2642 			 * global "peripheral_clk" clock.
2643 			 */
2644 			clk = devm_clk_get(dev, "peripheral_clk");
2645 			if (!IS_ERR(clk))
2646 				goto found;
2647 
2648 			dev_err(dev, "failed to get %s (%ld)\n", clk_names[i],
2649 				PTR_ERR(clk));
2650 			return PTR_ERR(clk);
2651 		}
2652 
2653 found:
2654 		if (IS_ERR(clk))
2655 			dev_dbg(dev, "failed to get %s (%ld)\n", clk_names[i],
2656 				PTR_ERR(clk));
2657 		else
2658 			dev_dbg(dev, "clk %s is %pC rate %pCr\n", clk_names[i],
2659 				clk, clk);
2660 		sci_port->clks[i] = IS_ERR(clk) ? NULL : clk;
2661 	}
2662 	return 0;
2663 }
2664 
2665 static const struct sci_port_params *
2666 sci_probe_regmap(const struct plat_sci_port *cfg)
2667 {
2668 	unsigned int regtype;
2669 
2670 	if (cfg->regtype != SCIx_PROBE_REGTYPE)
2671 		return &sci_port_params[cfg->regtype];
2672 
2673 	switch (cfg->type) {
2674 	case PORT_SCI:
2675 		regtype = SCIx_SCI_REGTYPE;
2676 		break;
2677 	case PORT_IRDA:
2678 		regtype = SCIx_IRDA_REGTYPE;
2679 		break;
2680 	case PORT_SCIFA:
2681 		regtype = SCIx_SCIFA_REGTYPE;
2682 		break;
2683 	case PORT_SCIFB:
2684 		regtype = SCIx_SCIFB_REGTYPE;
2685 		break;
2686 	case PORT_SCIF:
2687 		/*
2688 		 * The SH-4 is a bit of a misnomer here, although that's
2689 		 * where this particular port layout originated. This
2690 		 * configuration (or some slight variation thereof)
2691 		 * remains the dominant model for all SCIFs.
2692 		 */
2693 		regtype = SCIx_SH4_SCIF_REGTYPE;
2694 		break;
2695 	case PORT_HSCIF:
2696 		regtype = SCIx_HSCIF_REGTYPE;
2697 		break;
2698 	default:
2699 		pr_err("Can't probe register map for given port\n");
2700 		return NULL;
2701 	}
2702 
2703 	return &sci_port_params[regtype];
2704 }
2705 
2706 static int sci_init_single(struct platform_device *dev,
2707 			   struct sci_port *sci_port, unsigned int index,
2708 			   const struct plat_sci_port *p, bool early)
2709 {
2710 	struct uart_port *port = &sci_port->port;
2711 	const struct resource *res;
2712 	unsigned int i;
2713 	int ret;
2714 
2715 	sci_port->cfg	= p;
2716 
2717 	port->ops	= &sci_uart_ops;
2718 	port->iotype	= UPIO_MEM;
2719 	port->line	= index;
2720 
2721 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
2722 	if (res == NULL)
2723 		return -ENOMEM;
2724 
2725 	port->mapbase = res->start;
2726 	sci_port->reg_size = resource_size(res);
2727 
2728 	for (i = 0; i < ARRAY_SIZE(sci_port->irqs); ++i)
2729 		sci_port->irqs[i] = platform_get_irq(dev, i);
2730 
2731 	/* The SCI generates several interrupts. They can be muxed together or
2732 	 * connected to different interrupt lines. In the muxed case only one
2733 	 * interrupt resource is specified. In the non-muxed case three or four
2734 	 * interrupt resources are specified, as the BRI interrupt is optional.
2735 	 */
2736 	if (sci_port->irqs[0] < 0)
2737 		return -ENXIO;
2738 
2739 	if (sci_port->irqs[1] < 0) {
2740 		sci_port->irqs[1] = sci_port->irqs[0];
2741 		sci_port->irqs[2] = sci_port->irqs[0];
2742 		sci_port->irqs[3] = sci_port->irqs[0];
2743 	}
2744 
2745 	sci_port->params = sci_probe_regmap(p);
2746 	if (unlikely(sci_port->params == NULL))
2747 		return -EINVAL;
2748 
2749 	switch (p->type) {
2750 	case PORT_SCIFB:
2751 		sci_port->rx_trigger = 48;
2752 		break;
2753 	case PORT_HSCIF:
2754 		sci_port->rx_trigger = 64;
2755 		break;
2756 	case PORT_SCIFA:
2757 		sci_port->rx_trigger = 32;
2758 		break;
2759 	case PORT_SCIF:
2760 		if (p->regtype == SCIx_SH7705_SCIF_REGTYPE)
2761 			/* RX triggering not implemented for this IP */
2762 			sci_port->rx_trigger = 1;
2763 		else
2764 			sci_port->rx_trigger = 8;
2765 		break;
2766 	default:
2767 		sci_port->rx_trigger = 1;
2768 		break;
2769 	}
2770 
2771 	sci_port->rx_fifo_timeout = 0;
2772 
2773 	/* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't
2774 	 * match the SoC datasheet, this should be investigated. Let platform
2775 	 * data override the sampling rate for now.
2776 	 */
2777 	sci_port->sampling_rate_mask = p->sampling_rate
2778 				     ? SCI_SR(p->sampling_rate)
2779 				     : sci_port->params->sampling_rate_mask;
2780 
2781 	if (!early) {
2782 		ret = sci_init_clocks(sci_port, &dev->dev);
2783 		if (ret < 0)
2784 			return ret;
2785 
2786 		port->dev = &dev->dev;
2787 
2788 		pm_runtime_enable(&dev->dev);
2789 	}
2790 
2791 	port->type		= p->type;
2792 	port->flags		= UPF_FIXED_PORT | UPF_BOOT_AUTOCONF | p->flags;
2793 	port->fifosize		= sci_port->params->fifosize;
2794 
2795 	if (port->type == PORT_SCI) {
2796 		if (sci_port->reg_size >= 0x20)
2797 			port->regshift = 2;
2798 		else
2799 			port->regshift = 1;
2800 	}
2801 
2802 	/*
2803 	 * The UART port needs an IRQ value, so we peg this to the RX IRQ
2804 	 * for the multi-IRQ ports, which is where we are primarily
2805 	 * concerned with the shutdown path synchronization.
2806 	 *
2807 	 * For the muxed case there's nothing more to do.
2808 	 */
2809 	port->irq		= sci_port->irqs[SCIx_RXI_IRQ];
2810 	port->irqflags		= 0;
2811 
2812 	port->serial_in		= sci_serial_in;
2813 	port->serial_out	= sci_serial_out;
2814 
2815 	return 0;
2816 }
2817 
2818 static void sci_cleanup_single(struct sci_port *port)
2819 {
2820 	pm_runtime_disable(port->port.dev);
2821 }
2822 
2823 #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
2824     defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
2825 static void serial_console_putchar(struct uart_port *port, int ch)
2826 {
2827 	sci_poll_put_char(port, ch);
2828 }
2829 
2830 /*
2831  *	Print a string to the serial port trying not to disturb
2832  *	any possible real use of the port...
2833  */
2834 static void serial_console_write(struct console *co, const char *s,
2835 				 unsigned count)
2836 {
2837 	struct sci_port *sci_port = &sci_ports[co->index];
2838 	struct uart_port *port = &sci_port->port;
2839 	unsigned short bits, ctrl, ctrl_temp;
2840 	unsigned long flags;
2841 	int locked = 1;
2842 
2843 	local_irq_save(flags);
2844 #if defined(SUPPORT_SYSRQ)
2845 	if (port->sysrq)
2846 		locked = 0;
2847 	else
2848 #endif
2849 	if (oops_in_progress)
2850 		locked = spin_trylock(&port->lock);
2851 	else
2852 		spin_lock(&port->lock);
2853 
2854 	/* first save SCSCR then disable interrupts, keep clock source */
2855 	ctrl = serial_port_in(port, SCSCR);
2856 	ctrl_temp = SCSCR_RE | SCSCR_TE |
2857 		    (sci_port->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0)) |
2858 		    (ctrl & (SCSCR_CKE1 | SCSCR_CKE0));
2859 	serial_port_out(port, SCSCR, ctrl_temp);
2860 
2861 	uart_console_write(port, s, count, serial_console_putchar);
2862 
2863 	/* wait until fifo is empty and last bit has been transmitted */
2864 	bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
2865 	while ((serial_port_in(port, SCxSR) & bits) != bits)
2866 		cpu_relax();
2867 
2868 	/* restore the SCSCR */
2869 	serial_port_out(port, SCSCR, ctrl);
2870 
2871 	if (locked)
2872 		spin_unlock(&port->lock);
2873 	local_irq_restore(flags);
2874 }
2875 
2876 static int serial_console_setup(struct console *co, char *options)
2877 {
2878 	struct sci_port *sci_port;
2879 	struct uart_port *port;
2880 	int baud = 115200;
2881 	int bits = 8;
2882 	int parity = 'n';
2883 	int flow = 'n';
2884 	int ret;
2885 
2886 	/*
2887 	 * Refuse to handle any bogus ports.
2888 	 */
2889 	if (co->index < 0 || co->index >= SCI_NPORTS)
2890 		return -ENODEV;
2891 
2892 	sci_port = &sci_ports[co->index];
2893 	port = &sci_port->port;
2894 
2895 	/*
2896 	 * Refuse to handle uninitialized ports.
2897 	 */
2898 	if (!port->ops)
2899 		return -ENODEV;
2900 
2901 	ret = sci_remap_port(port);
2902 	if (unlikely(ret != 0))
2903 		return ret;
2904 
2905 	if (options)
2906 		uart_parse_options(options, &baud, &parity, &bits, &flow);
2907 
2908 	return uart_set_options(port, co, baud, parity, bits, flow);
2909 }
2910 
2911 static struct console serial_console = {
2912 	.name		= "ttySC",
2913 	.device		= uart_console_device,
2914 	.write		= serial_console_write,
2915 	.setup		= serial_console_setup,
2916 	.flags		= CON_PRINTBUFFER,
2917 	.index		= -1,
2918 	.data		= &sci_uart_driver,
2919 };
2920 
2921 static struct console early_serial_console = {
2922 	.name           = "early_ttySC",
2923 	.write          = serial_console_write,
2924 	.flags          = CON_PRINTBUFFER,
2925 	.index		= -1,
2926 };
2927 
2928 static char early_serial_buf[32];
2929 
2930 static int sci_probe_earlyprintk(struct platform_device *pdev)
2931 {
2932 	const struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev);
2933 
2934 	if (early_serial_console.data)
2935 		return -EEXIST;
2936 
2937 	early_serial_console.index = pdev->id;
2938 
2939 	sci_init_single(pdev, &sci_ports[pdev->id], pdev->id, cfg, true);
2940 
2941 	serial_console_setup(&early_serial_console, early_serial_buf);
2942 
2943 	if (!strstr(early_serial_buf, "keep"))
2944 		early_serial_console.flags |= CON_BOOT;
2945 
2946 	register_console(&early_serial_console);
2947 	return 0;
2948 }
2949 
2950 #define SCI_CONSOLE	(&serial_console)
2951 
2952 #else
2953 static inline int sci_probe_earlyprintk(struct platform_device *pdev)
2954 {
2955 	return -EINVAL;
2956 }
2957 
2958 #define SCI_CONSOLE	NULL
2959 
2960 #endif /* CONFIG_SERIAL_SH_SCI_CONSOLE || CONFIG_SERIAL_SH_SCI_EARLYCON */
2961 
2962 static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized";
2963 
2964 static DEFINE_MUTEX(sci_uart_registration_lock);
2965 static struct uart_driver sci_uart_driver = {
2966 	.owner		= THIS_MODULE,
2967 	.driver_name	= "sci",
2968 	.dev_name	= "ttySC",
2969 	.major		= SCI_MAJOR,
2970 	.minor		= SCI_MINOR_START,
2971 	.nr		= SCI_NPORTS,
2972 	.cons		= SCI_CONSOLE,
2973 };
2974 
2975 static int sci_remove(struct platform_device *dev)
2976 {
2977 	struct sci_port *port = platform_get_drvdata(dev);
2978 
2979 	uart_remove_one_port(&sci_uart_driver, &port->port);
2980 
2981 	sci_cleanup_single(port);
2982 
2983 	if (port->port.fifosize > 1) {
2984 		sysfs_remove_file(&dev->dev.kobj,
2985 				  &dev_attr_rx_fifo_trigger.attr);
2986 	}
2987 	if (port->port.type == PORT_SCIFA || port->port.type == PORT_SCIFB) {
2988 		sysfs_remove_file(&dev->dev.kobj,
2989 				  &dev_attr_rx_fifo_timeout.attr);
2990 	}
2991 
2992 	return 0;
2993 }
2994 
2995 
2996 #define SCI_OF_DATA(type, regtype)	(void *)((type) << 16 | (regtype))
2997 #define SCI_OF_TYPE(data)		((unsigned long)(data) >> 16)
2998 #define SCI_OF_REGTYPE(data)		((unsigned long)(data) & 0xffff)
2999 
3000 static const struct of_device_id of_sci_match[] = {
3001 	/* SoC-specific types */
3002 	{
3003 		.compatible = "renesas,scif-r7s72100",
3004 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH2_SCIF_FIFODATA_REGTYPE),
3005 	},
3006 	/* Family-specific types */
3007 	{
3008 		.compatible = "renesas,rcar-gen1-scif",
3009 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3010 	}, {
3011 		.compatible = "renesas,rcar-gen2-scif",
3012 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3013 	}, {
3014 		.compatible = "renesas,rcar-gen3-scif",
3015 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3016 	},
3017 	/* Generic types */
3018 	{
3019 		.compatible = "renesas,scif",
3020 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_REGTYPE),
3021 	}, {
3022 		.compatible = "renesas,scifa",
3023 		.data = SCI_OF_DATA(PORT_SCIFA, SCIx_SCIFA_REGTYPE),
3024 	}, {
3025 		.compatible = "renesas,scifb",
3026 		.data = SCI_OF_DATA(PORT_SCIFB, SCIx_SCIFB_REGTYPE),
3027 	}, {
3028 		.compatible = "renesas,hscif",
3029 		.data = SCI_OF_DATA(PORT_HSCIF, SCIx_HSCIF_REGTYPE),
3030 	}, {
3031 		.compatible = "renesas,sci",
3032 		.data = SCI_OF_DATA(PORT_SCI, SCIx_SCI_REGTYPE),
3033 	}, {
3034 		/* Terminator */
3035 	},
3036 };
3037 MODULE_DEVICE_TABLE(of, of_sci_match);
3038 
3039 static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev,
3040 					  unsigned int *dev_id)
3041 {
3042 	struct device_node *np = pdev->dev.of_node;
3043 	const struct of_device_id *match;
3044 	struct plat_sci_port *p;
3045 	struct sci_port *sp;
3046 	int id;
3047 
3048 	if (!IS_ENABLED(CONFIG_OF) || !np)
3049 		return NULL;
3050 
3051 	match = of_match_node(of_sci_match, np);
3052 	if (!match)
3053 		return NULL;
3054 
3055 	p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
3056 	if (!p)
3057 		return NULL;
3058 
3059 	/* Get the line number from the aliases node. */
3060 	id = of_alias_get_id(np, "serial");
3061 	if (id < 0) {
3062 		dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
3063 		return NULL;
3064 	}
3065 
3066 	sp = &sci_ports[id];
3067 	*dev_id = id;
3068 
3069 	p->type = SCI_OF_TYPE(match->data);
3070 	p->regtype = SCI_OF_REGTYPE(match->data);
3071 
3072 	if (of_find_property(np, "uart-has-rtscts", NULL))
3073 		sp->has_rtscts = true;
3074 
3075 	return p;
3076 }
3077 
3078 static int sci_probe_single(struct platform_device *dev,
3079 				      unsigned int index,
3080 				      struct plat_sci_port *p,
3081 				      struct sci_port *sciport)
3082 {
3083 	int ret;
3084 
3085 	/* Sanity check */
3086 	if (unlikely(index >= SCI_NPORTS)) {
3087 		dev_notice(&dev->dev, "Attempting to register port %d when only %d are available\n",
3088 			   index+1, SCI_NPORTS);
3089 		dev_notice(&dev->dev, "Consider bumping CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
3090 		return -EINVAL;
3091 	}
3092 
3093 	mutex_lock(&sci_uart_registration_lock);
3094 	if (!sci_uart_driver.state) {
3095 		ret = uart_register_driver(&sci_uart_driver);
3096 		if (ret) {
3097 			mutex_unlock(&sci_uart_registration_lock);
3098 			return ret;
3099 		}
3100 	}
3101 	mutex_unlock(&sci_uart_registration_lock);
3102 
3103 	ret = sci_init_single(dev, sciport, index, p, false);
3104 	if (ret)
3105 		return ret;
3106 
3107 	sciport->gpios = mctrl_gpio_init(&sciport->port, 0);
3108 	if (IS_ERR(sciport->gpios) && PTR_ERR(sciport->gpios) != -ENOSYS)
3109 		return PTR_ERR(sciport->gpios);
3110 
3111 	if (sciport->has_rtscts) {
3112 		if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(sciport->gpios,
3113 							UART_GPIO_CTS)) ||
3114 		    !IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(sciport->gpios,
3115 							UART_GPIO_RTS))) {
3116 			dev_err(&dev->dev, "Conflicting RTS/CTS config\n");
3117 			return -EINVAL;
3118 		}
3119 		sciport->port.flags |= UPF_HARD_FLOW;
3120 	}
3121 
3122 	ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
3123 	if (ret) {
3124 		sci_cleanup_single(sciport);
3125 		return ret;
3126 	}
3127 
3128 	return 0;
3129 }
3130 
3131 static int sci_probe(struct platform_device *dev)
3132 {
3133 	struct plat_sci_port *p;
3134 	struct sci_port *sp;
3135 	unsigned int dev_id;
3136 	int ret;
3137 
3138 	/*
3139 	 * If we've come here via earlyprintk initialization, head off to
3140 	 * the special early probe. We don't have sufficient device state
3141 	 * to make it beyond this yet.
3142 	 */
3143 	if (is_early_platform_device(dev))
3144 		return sci_probe_earlyprintk(dev);
3145 
3146 	if (dev->dev.of_node) {
3147 		p = sci_parse_dt(dev, &dev_id);
3148 		if (p == NULL)
3149 			return -EINVAL;
3150 	} else {
3151 		p = dev->dev.platform_data;
3152 		if (p == NULL) {
3153 			dev_err(&dev->dev, "no platform data supplied\n");
3154 			return -EINVAL;
3155 		}
3156 
3157 		dev_id = dev->id;
3158 	}
3159 
3160 	sp = &sci_ports[dev_id];
3161 	platform_set_drvdata(dev, sp);
3162 
3163 	ret = sci_probe_single(dev, dev_id, p, sp);
3164 	if (ret)
3165 		return ret;
3166 
3167 	if (sp->port.fifosize > 1) {
3168 		ret = sysfs_create_file(&dev->dev.kobj,
3169 				&dev_attr_rx_fifo_trigger.attr);
3170 		if (ret)
3171 			return ret;
3172 	}
3173 	if (sp->port.type == PORT_SCIFA || sp->port.type ==  PORT_SCIFB) {
3174 		ret = sysfs_create_file(&dev->dev.kobj,
3175 				&dev_attr_rx_fifo_timeout.attr);
3176 		if (ret) {
3177 			if (sp->port.fifosize > 1) {
3178 				sysfs_remove_file(&dev->dev.kobj,
3179 					&dev_attr_rx_fifo_trigger.attr);
3180 			}
3181 			return ret;
3182 		}
3183 	}
3184 
3185 #ifdef CONFIG_SH_STANDARD_BIOS
3186 	sh_bios_gdb_detach();
3187 #endif
3188 
3189 	return 0;
3190 }
3191 
3192 static __maybe_unused int sci_suspend(struct device *dev)
3193 {
3194 	struct sci_port *sport = dev_get_drvdata(dev);
3195 
3196 	if (sport)
3197 		uart_suspend_port(&sci_uart_driver, &sport->port);
3198 
3199 	return 0;
3200 }
3201 
3202 static __maybe_unused int sci_resume(struct device *dev)
3203 {
3204 	struct sci_port *sport = dev_get_drvdata(dev);
3205 
3206 	if (sport)
3207 		uart_resume_port(&sci_uart_driver, &sport->port);
3208 
3209 	return 0;
3210 }
3211 
3212 static SIMPLE_DEV_PM_OPS(sci_dev_pm_ops, sci_suspend, sci_resume);
3213 
3214 static struct platform_driver sci_driver = {
3215 	.probe		= sci_probe,
3216 	.remove		= sci_remove,
3217 	.driver		= {
3218 		.name	= "sh-sci",
3219 		.pm	= &sci_dev_pm_ops,
3220 		.of_match_table = of_match_ptr(of_sci_match),
3221 	},
3222 };
3223 
3224 static int __init sci_init(void)
3225 {
3226 	pr_info("%s\n", banner);
3227 
3228 	return platform_driver_register(&sci_driver);
3229 }
3230 
3231 static void __exit sci_exit(void)
3232 {
3233 	platform_driver_unregister(&sci_driver);
3234 
3235 	if (sci_uart_driver.state)
3236 		uart_unregister_driver(&sci_uart_driver);
3237 }
3238 
3239 #ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
3240 early_platform_init_buffer("earlyprintk", &sci_driver,
3241 			   early_serial_buf, ARRAY_SIZE(early_serial_buf));
3242 #endif
3243 #ifdef CONFIG_SERIAL_SH_SCI_EARLYCON
3244 static struct __init plat_sci_port port_cfg;
3245 
3246 static int __init early_console_setup(struct earlycon_device *device,
3247 				      int type)
3248 {
3249 	if (!device->port.membase)
3250 		return -ENODEV;
3251 
3252 	device->port.serial_in = sci_serial_in;
3253 	device->port.serial_out	= sci_serial_out;
3254 	device->port.type = type;
3255 	memcpy(&sci_ports[0].port, &device->port, sizeof(struct uart_port));
3256 	port_cfg.type = type;
3257 	sci_ports[0].cfg = &port_cfg;
3258 	sci_ports[0].params = sci_probe_regmap(&port_cfg);
3259 	port_cfg.scscr = sci_serial_in(&sci_ports[0].port, SCSCR);
3260 	sci_serial_out(&sci_ports[0].port, SCSCR,
3261 		       SCSCR_RE | SCSCR_TE | port_cfg.scscr);
3262 
3263 	device->con->write = serial_console_write;
3264 	return 0;
3265 }
3266 static int __init sci_early_console_setup(struct earlycon_device *device,
3267 					  const char *opt)
3268 {
3269 	return early_console_setup(device, PORT_SCI);
3270 }
3271 static int __init scif_early_console_setup(struct earlycon_device *device,
3272 					  const char *opt)
3273 {
3274 	return early_console_setup(device, PORT_SCIF);
3275 }
3276 static int __init scifa_early_console_setup(struct earlycon_device *device,
3277 					  const char *opt)
3278 {
3279 	return early_console_setup(device, PORT_SCIFA);
3280 }
3281 static int __init scifb_early_console_setup(struct earlycon_device *device,
3282 					  const char *opt)
3283 {
3284 	return early_console_setup(device, PORT_SCIFB);
3285 }
3286 static int __init hscif_early_console_setup(struct earlycon_device *device,
3287 					  const char *opt)
3288 {
3289 	return early_console_setup(device, PORT_HSCIF);
3290 }
3291 
3292 OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup);
3293 OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup);
3294 OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup);
3295 OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup);
3296 OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup);
3297 #endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */
3298 
3299 module_init(sci_init);
3300 module_exit(sci_exit);
3301 
3302 MODULE_LICENSE("GPL");
3303 MODULE_ALIAS("platform:sh-sci");
3304 MODULE_AUTHOR("Paul Mundt");
3305 MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver");
3306