xref: /openbmc/linux/drivers/tty/serial/fsl_lpuart.c (revision 92a2c6b2)
1 /*
2  *  Freescale lpuart serial port driver
3  *
4  *  Copyright 2012-2014 Freescale Semiconductor, Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  */
11 
12 #if defined(CONFIG_SERIAL_FSL_LPUART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
13 #define SUPPORT_SYSRQ
14 #endif
15 
16 #include <linux/clk.h>
17 #include <linux/console.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/dmaengine.h>
20 #include <linux/dmapool.h>
21 #include <linux/io.h>
22 #include <linux/irq.h>
23 #include <linux/module.h>
24 #include <linux/of.h>
25 #include <linux/of_device.h>
26 #include <linux/of_dma.h>
27 #include <linux/serial_core.h>
28 #include <linux/slab.h>
29 #include <linux/tty_flip.h>
30 
31 /* All registers are 8-bit width */
32 #define UARTBDH			0x00
33 #define UARTBDL			0x01
34 #define UARTCR1			0x02
35 #define UARTCR2			0x03
36 #define UARTSR1			0x04
37 #define UARTCR3			0x06
38 #define UARTDR			0x07
39 #define UARTCR4			0x0a
40 #define UARTCR5			0x0b
41 #define UARTMODEM		0x0d
42 #define UARTPFIFO		0x10
43 #define UARTCFIFO		0x11
44 #define UARTSFIFO		0x12
45 #define UARTTWFIFO		0x13
46 #define UARTTCFIFO		0x14
47 #define UARTRWFIFO		0x15
48 
49 #define UARTBDH_LBKDIE		0x80
50 #define UARTBDH_RXEDGIE		0x40
51 #define UARTBDH_SBR_MASK	0x1f
52 
53 #define UARTCR1_LOOPS		0x80
54 #define UARTCR1_RSRC		0x20
55 #define UARTCR1_M		0x10
56 #define UARTCR1_WAKE		0x08
57 #define UARTCR1_ILT		0x04
58 #define UARTCR1_PE		0x02
59 #define UARTCR1_PT		0x01
60 
61 #define UARTCR2_TIE		0x80
62 #define UARTCR2_TCIE		0x40
63 #define UARTCR2_RIE		0x20
64 #define UARTCR2_ILIE		0x10
65 #define UARTCR2_TE		0x08
66 #define UARTCR2_RE		0x04
67 #define UARTCR2_RWU		0x02
68 #define UARTCR2_SBK		0x01
69 
70 #define UARTSR1_TDRE		0x80
71 #define UARTSR1_TC		0x40
72 #define UARTSR1_RDRF		0x20
73 #define UARTSR1_IDLE		0x10
74 #define UARTSR1_OR		0x08
75 #define UARTSR1_NF		0x04
76 #define UARTSR1_FE		0x02
77 #define UARTSR1_PE		0x01
78 
79 #define UARTCR3_R8		0x80
80 #define UARTCR3_T8		0x40
81 #define UARTCR3_TXDIR		0x20
82 #define UARTCR3_TXINV		0x10
83 #define UARTCR3_ORIE		0x08
84 #define UARTCR3_NEIE		0x04
85 #define UARTCR3_FEIE		0x02
86 #define UARTCR3_PEIE		0x01
87 
88 #define UARTCR4_MAEN1		0x80
89 #define UARTCR4_MAEN2		0x40
90 #define UARTCR4_M10		0x20
91 #define UARTCR4_BRFA_MASK	0x1f
92 #define UARTCR4_BRFA_OFF	0
93 
94 #define UARTCR5_TDMAS		0x80
95 #define UARTCR5_RDMAS		0x20
96 
97 #define UARTMODEM_RXRTSE	0x08
98 #define UARTMODEM_TXRTSPOL	0x04
99 #define UARTMODEM_TXRTSE	0x02
100 #define UARTMODEM_TXCTSE	0x01
101 
102 #define UARTPFIFO_TXFE		0x80
103 #define UARTPFIFO_FIFOSIZE_MASK	0x7
104 #define UARTPFIFO_TXSIZE_OFF	4
105 #define UARTPFIFO_RXFE		0x08
106 #define UARTPFIFO_RXSIZE_OFF	0
107 
108 #define UARTCFIFO_TXFLUSH	0x80
109 #define UARTCFIFO_RXFLUSH	0x40
110 #define UARTCFIFO_RXOFE		0x04
111 #define UARTCFIFO_TXOFE		0x02
112 #define UARTCFIFO_RXUFE		0x01
113 
114 #define UARTSFIFO_TXEMPT	0x80
115 #define UARTSFIFO_RXEMPT	0x40
116 #define UARTSFIFO_RXOF		0x04
117 #define UARTSFIFO_TXOF		0x02
118 #define UARTSFIFO_RXUF		0x01
119 
120 /* 32-bit register defination */
121 #define UARTBAUD		0x00
122 #define UARTSTAT		0x04
123 #define UARTCTRL		0x08
124 #define UARTDATA		0x0C
125 #define UARTMATCH		0x10
126 #define UARTMODIR		0x14
127 #define UARTFIFO		0x18
128 #define UARTWATER		0x1c
129 
130 #define UARTBAUD_MAEN1		0x80000000
131 #define UARTBAUD_MAEN2		0x40000000
132 #define UARTBAUD_M10		0x20000000
133 #define UARTBAUD_TDMAE		0x00800000
134 #define UARTBAUD_RDMAE		0x00200000
135 #define UARTBAUD_MATCFG		0x00400000
136 #define UARTBAUD_BOTHEDGE	0x00020000
137 #define UARTBAUD_RESYNCDIS	0x00010000
138 #define UARTBAUD_LBKDIE		0x00008000
139 #define UARTBAUD_RXEDGIE	0x00004000
140 #define UARTBAUD_SBNS		0x00002000
141 #define UARTBAUD_SBR		0x00000000
142 #define UARTBAUD_SBR_MASK	0x1fff
143 
144 #define UARTSTAT_LBKDIF		0x80000000
145 #define UARTSTAT_RXEDGIF	0x40000000
146 #define UARTSTAT_MSBF		0x20000000
147 #define UARTSTAT_RXINV		0x10000000
148 #define UARTSTAT_RWUID		0x08000000
149 #define UARTSTAT_BRK13		0x04000000
150 #define UARTSTAT_LBKDE		0x02000000
151 #define UARTSTAT_RAF		0x01000000
152 #define UARTSTAT_TDRE		0x00800000
153 #define UARTSTAT_TC		0x00400000
154 #define UARTSTAT_RDRF		0x00200000
155 #define UARTSTAT_IDLE		0x00100000
156 #define UARTSTAT_OR		0x00080000
157 #define UARTSTAT_NF		0x00040000
158 #define UARTSTAT_FE		0x00020000
159 #define UARTSTAT_PE		0x00010000
160 #define UARTSTAT_MA1F		0x00008000
161 #define UARTSTAT_M21F		0x00004000
162 
163 #define UARTCTRL_R8T9		0x80000000
164 #define UARTCTRL_R9T8		0x40000000
165 #define UARTCTRL_TXDIR		0x20000000
166 #define UARTCTRL_TXINV		0x10000000
167 #define UARTCTRL_ORIE		0x08000000
168 #define UARTCTRL_NEIE		0x04000000
169 #define UARTCTRL_FEIE		0x02000000
170 #define UARTCTRL_PEIE		0x01000000
171 #define UARTCTRL_TIE		0x00800000
172 #define UARTCTRL_TCIE		0x00400000
173 #define UARTCTRL_RIE		0x00200000
174 #define UARTCTRL_ILIE		0x00100000
175 #define UARTCTRL_TE		0x00080000
176 #define UARTCTRL_RE		0x00040000
177 #define UARTCTRL_RWU		0x00020000
178 #define UARTCTRL_SBK		0x00010000
179 #define UARTCTRL_MA1IE		0x00008000
180 #define UARTCTRL_MA2IE		0x00004000
181 #define UARTCTRL_IDLECFG	0x00000100
182 #define UARTCTRL_LOOPS		0x00000080
183 #define UARTCTRL_DOZEEN		0x00000040
184 #define UARTCTRL_RSRC		0x00000020
185 #define UARTCTRL_M		0x00000010
186 #define UARTCTRL_WAKE		0x00000008
187 #define UARTCTRL_ILT		0x00000004
188 #define UARTCTRL_PE		0x00000002
189 #define UARTCTRL_PT		0x00000001
190 
191 #define UARTDATA_NOISY		0x00008000
192 #define UARTDATA_PARITYE	0x00004000
193 #define UARTDATA_FRETSC		0x00002000
194 #define UARTDATA_RXEMPT		0x00001000
195 #define UARTDATA_IDLINE		0x00000800
196 #define UARTDATA_MASK		0x3ff
197 
198 #define UARTMODIR_IREN		0x00020000
199 #define UARTMODIR_TXCTSSRC	0x00000020
200 #define UARTMODIR_TXCTSC	0x00000010
201 #define UARTMODIR_RXRTSE	0x00000008
202 #define UARTMODIR_TXRTSPOL	0x00000004
203 #define UARTMODIR_TXRTSE	0x00000002
204 #define UARTMODIR_TXCTSE	0x00000001
205 
206 #define UARTFIFO_TXEMPT		0x00800000
207 #define UARTFIFO_RXEMPT		0x00400000
208 #define UARTFIFO_TXOF		0x00020000
209 #define UARTFIFO_RXUF		0x00010000
210 #define UARTFIFO_TXFLUSH	0x00008000
211 #define UARTFIFO_RXFLUSH	0x00004000
212 #define UARTFIFO_TXOFE		0x00000200
213 #define UARTFIFO_RXUFE		0x00000100
214 #define UARTFIFO_TXFE		0x00000080
215 #define UARTFIFO_FIFOSIZE_MASK	0x7
216 #define UARTFIFO_TXSIZE_OFF	4
217 #define UARTFIFO_RXFE		0x00000008
218 #define UARTFIFO_RXSIZE_OFF	0
219 
220 #define UARTWATER_COUNT_MASK	0xff
221 #define UARTWATER_TXCNT_OFF	8
222 #define UARTWATER_RXCNT_OFF	24
223 #define UARTWATER_WATER_MASK	0xff
224 #define UARTWATER_TXWATER_OFF	0
225 #define UARTWATER_RXWATER_OFF	16
226 
227 #define FSL_UART_RX_DMA_BUFFER_SIZE	64
228 
229 #define DRIVER_NAME	"fsl-lpuart"
230 #define DEV_NAME	"ttyLP"
231 #define UART_NR		6
232 
233 struct lpuart_port {
234 	struct uart_port	port;
235 	struct clk		*clk;
236 	unsigned int		txfifo_size;
237 	unsigned int		rxfifo_size;
238 	bool			lpuart32;
239 
240 	bool			lpuart_dma_tx_use;
241 	bool			lpuart_dma_rx_use;
242 	struct dma_chan		*dma_tx_chan;
243 	struct dma_chan		*dma_rx_chan;
244 	struct dma_async_tx_descriptor  *dma_tx_desc;
245 	struct dma_async_tx_descriptor  *dma_rx_desc;
246 	dma_addr_t		dma_tx_buf_bus;
247 	dma_addr_t		dma_rx_buf_bus;
248 	dma_cookie_t		dma_tx_cookie;
249 	dma_cookie_t		dma_rx_cookie;
250 	unsigned char		*dma_tx_buf_virt;
251 	unsigned char		*dma_rx_buf_virt;
252 	unsigned int		dma_tx_bytes;
253 	unsigned int		dma_rx_bytes;
254 	int			dma_tx_in_progress;
255 	int			dma_rx_in_progress;
256 	unsigned int		dma_rx_timeout;
257 	struct timer_list	lpuart_timer;
258 };
259 
260 static struct of_device_id lpuart_dt_ids[] = {
261 	{
262 		.compatible = "fsl,vf610-lpuart",
263 	},
264 	{
265 		.compatible = "fsl,ls1021a-lpuart",
266 	},
267 	{ /* sentinel */ }
268 };
269 MODULE_DEVICE_TABLE(of, lpuart_dt_ids);
270 
271 /* Forward declare this for the dma callbacks*/
272 static void lpuart_dma_tx_complete(void *arg);
273 static void lpuart_dma_rx_complete(void *arg);
274 
275 static u32 lpuart32_read(void __iomem *addr)
276 {
277 	return ioread32be(addr);
278 }
279 
280 static void lpuart32_write(u32 val, void __iomem *addr)
281 {
282 	iowrite32be(val, addr);
283 }
284 
285 static void lpuart_stop_tx(struct uart_port *port)
286 {
287 	unsigned char temp;
288 
289 	temp = readb(port->membase + UARTCR2);
290 	temp &= ~(UARTCR2_TIE | UARTCR2_TCIE);
291 	writeb(temp, port->membase + UARTCR2);
292 }
293 
294 static void lpuart32_stop_tx(struct uart_port *port)
295 {
296 	unsigned long temp;
297 
298 	temp = lpuart32_read(port->membase + UARTCTRL);
299 	temp &= ~(UARTCTRL_TIE | UARTCTRL_TCIE);
300 	lpuart32_write(temp, port->membase + UARTCTRL);
301 }
302 
303 static void lpuart_stop_rx(struct uart_port *port)
304 {
305 	unsigned char temp;
306 
307 	temp = readb(port->membase + UARTCR2);
308 	writeb(temp & ~UARTCR2_RE, port->membase + UARTCR2);
309 }
310 
311 static void lpuart32_stop_rx(struct uart_port *port)
312 {
313 	unsigned long temp;
314 
315 	temp = lpuart32_read(port->membase + UARTCTRL);
316 	lpuart32_write(temp & ~UARTCTRL_RE, port->membase + UARTCTRL);
317 }
318 
319 static void lpuart_copy_rx_to_tty(struct lpuart_port *sport,
320 		struct tty_port *tty, int count)
321 {
322 	int copied;
323 
324 	sport->port.icount.rx += count;
325 
326 	if (!tty) {
327 		dev_err(sport->port.dev, "No tty port\n");
328 		return;
329 	}
330 
331 	dma_sync_single_for_cpu(sport->port.dev, sport->dma_rx_buf_bus,
332 			FSL_UART_RX_DMA_BUFFER_SIZE, DMA_FROM_DEVICE);
333 	copied = tty_insert_flip_string(tty,
334 			((unsigned char *)(sport->dma_rx_buf_virt)), count);
335 
336 	if (copied != count) {
337 		WARN_ON(1);
338 		dev_err(sport->port.dev, "RxData copy to tty layer failed\n");
339 	}
340 
341 	dma_sync_single_for_device(sport->port.dev, sport->dma_rx_buf_bus,
342 			FSL_UART_RX_DMA_BUFFER_SIZE, DMA_TO_DEVICE);
343 }
344 
345 static void lpuart_pio_tx(struct lpuart_port *sport)
346 {
347 	struct circ_buf *xmit = &sport->port.state->xmit;
348 	unsigned long flags;
349 
350 	spin_lock_irqsave(&sport->port.lock, flags);
351 
352 	while (!uart_circ_empty(xmit) &&
353 		readb(sport->port.membase + UARTTCFIFO) < sport->txfifo_size) {
354 		writeb(xmit->buf[xmit->tail], sport->port.membase + UARTDR);
355 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
356 		sport->port.icount.tx++;
357 	}
358 
359 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
360 		uart_write_wakeup(&sport->port);
361 
362 	if (uart_circ_empty(xmit))
363 		writeb(readb(sport->port.membase + UARTCR5) | UARTCR5_TDMAS,
364 			sport->port.membase + UARTCR5);
365 
366 	spin_unlock_irqrestore(&sport->port.lock, flags);
367 }
368 
369 static int lpuart_dma_tx(struct lpuart_port *sport, unsigned long count)
370 {
371 	struct circ_buf *xmit = &sport->port.state->xmit;
372 	dma_addr_t tx_bus_addr;
373 
374 	dma_sync_single_for_device(sport->port.dev, sport->dma_tx_buf_bus,
375 				UART_XMIT_SIZE, DMA_TO_DEVICE);
376 	sport->dma_tx_bytes = count & ~(sport->txfifo_size - 1);
377 	tx_bus_addr = sport->dma_tx_buf_bus + xmit->tail;
378 	sport->dma_tx_desc = dmaengine_prep_slave_single(sport->dma_tx_chan,
379 					tx_bus_addr, sport->dma_tx_bytes,
380 					DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
381 
382 	if (!sport->dma_tx_desc) {
383 		dev_err(sport->port.dev, "Not able to get desc for tx\n");
384 		return -EIO;
385 	}
386 
387 	sport->dma_tx_desc->callback = lpuart_dma_tx_complete;
388 	sport->dma_tx_desc->callback_param = sport;
389 	sport->dma_tx_in_progress = 1;
390 	sport->dma_tx_cookie = dmaengine_submit(sport->dma_tx_desc);
391 	dma_async_issue_pending(sport->dma_tx_chan);
392 
393 	return 0;
394 }
395 
396 static void lpuart_prepare_tx(struct lpuart_port *sport)
397 {
398 	struct circ_buf *xmit = &sport->port.state->xmit;
399 	unsigned long count =  CIRC_CNT_TO_END(xmit->head,
400 					xmit->tail, UART_XMIT_SIZE);
401 
402 	if (!count)
403 		return;
404 
405 	if (count < sport->txfifo_size)
406 		writeb(readb(sport->port.membase + UARTCR5) & ~UARTCR5_TDMAS,
407 				sport->port.membase + UARTCR5);
408 	else {
409 		writeb(readb(sport->port.membase + UARTCR5) | UARTCR5_TDMAS,
410 				sport->port.membase + UARTCR5);
411 		lpuart_dma_tx(sport, count);
412 	}
413 }
414 
415 static void lpuart_dma_tx_complete(void *arg)
416 {
417 	struct lpuart_port *sport = arg;
418 	struct circ_buf *xmit = &sport->port.state->xmit;
419 	unsigned long flags;
420 
421 	async_tx_ack(sport->dma_tx_desc);
422 
423 	spin_lock_irqsave(&sport->port.lock, flags);
424 
425 	xmit->tail = (xmit->tail + sport->dma_tx_bytes) & (UART_XMIT_SIZE - 1);
426 	sport->dma_tx_in_progress = 0;
427 
428 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
429 		uart_write_wakeup(&sport->port);
430 
431 	lpuart_prepare_tx(sport);
432 
433 	spin_unlock_irqrestore(&sport->port.lock, flags);
434 }
435 
436 static int lpuart_dma_rx(struct lpuart_port *sport)
437 {
438 	dma_sync_single_for_device(sport->port.dev, sport->dma_rx_buf_bus,
439 			FSL_UART_RX_DMA_BUFFER_SIZE, DMA_TO_DEVICE);
440 	sport->dma_rx_desc = dmaengine_prep_slave_single(sport->dma_rx_chan,
441 			sport->dma_rx_buf_bus, FSL_UART_RX_DMA_BUFFER_SIZE,
442 			DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT);
443 
444 	if (!sport->dma_rx_desc) {
445 		dev_err(sport->port.dev, "Not able to get desc for rx\n");
446 		return -EIO;
447 	}
448 
449 	sport->dma_rx_desc->callback = lpuart_dma_rx_complete;
450 	sport->dma_rx_desc->callback_param = sport;
451 	sport->dma_rx_in_progress = 1;
452 	sport->dma_rx_cookie = dmaengine_submit(sport->dma_rx_desc);
453 	dma_async_issue_pending(sport->dma_rx_chan);
454 
455 	return 0;
456 }
457 
458 static void lpuart_flush_buffer(struct uart_port *port)
459 {
460 	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
461 	if (sport->lpuart_dma_tx_use) {
462 		dmaengine_terminate_all(sport->dma_tx_chan);
463 		sport->dma_tx_in_progress = 0;
464 	}
465 }
466 
467 static void lpuart_dma_rx_complete(void *arg)
468 {
469 	struct lpuart_port *sport = arg;
470 	struct tty_port *port = &sport->port.state->port;
471 	unsigned long flags;
472 
473 	async_tx_ack(sport->dma_rx_desc);
474 	mod_timer(&sport->lpuart_timer, jiffies + sport->dma_rx_timeout);
475 
476 	spin_lock_irqsave(&sport->port.lock, flags);
477 
478 	sport->dma_rx_in_progress = 0;
479 	lpuart_copy_rx_to_tty(sport, port, FSL_UART_RX_DMA_BUFFER_SIZE);
480 	tty_flip_buffer_push(port);
481 	lpuart_dma_rx(sport);
482 
483 	spin_unlock_irqrestore(&sport->port.lock, flags);
484 }
485 
486 static void lpuart_timer_func(unsigned long data)
487 {
488 	struct lpuart_port *sport = (struct lpuart_port *)data;
489 	struct tty_port *port = &sport->port.state->port;
490 	struct dma_tx_state state;
491 	unsigned long flags;
492 	unsigned char temp;
493 	int count;
494 
495 	del_timer(&sport->lpuart_timer);
496 	dmaengine_pause(sport->dma_rx_chan);
497 	dmaengine_tx_status(sport->dma_rx_chan, sport->dma_rx_cookie, &state);
498 	dmaengine_terminate_all(sport->dma_rx_chan);
499 	count = FSL_UART_RX_DMA_BUFFER_SIZE - state.residue;
500 	async_tx_ack(sport->dma_rx_desc);
501 
502 	spin_lock_irqsave(&sport->port.lock, flags);
503 
504 	sport->dma_rx_in_progress = 0;
505 	lpuart_copy_rx_to_tty(sport, port, count);
506 	tty_flip_buffer_push(port);
507 	temp = readb(sport->port.membase + UARTCR5);
508 	writeb(temp & ~UARTCR5_RDMAS, sport->port.membase + UARTCR5);
509 
510 	spin_unlock_irqrestore(&sport->port.lock, flags);
511 }
512 
513 static inline void lpuart_prepare_rx(struct lpuart_port *sport)
514 {
515 	unsigned long flags;
516 	unsigned char temp;
517 
518 	spin_lock_irqsave(&sport->port.lock, flags);
519 
520 	sport->lpuart_timer.expires = jiffies + sport->dma_rx_timeout;
521 	add_timer(&sport->lpuart_timer);
522 
523 	lpuart_dma_rx(sport);
524 	temp = readb(sport->port.membase + UARTCR5);
525 	writeb(temp | UARTCR5_RDMAS, sport->port.membase + UARTCR5);
526 
527 	spin_unlock_irqrestore(&sport->port.lock, flags);
528 }
529 
530 static inline void lpuart_transmit_buffer(struct lpuart_port *sport)
531 {
532 	struct circ_buf *xmit = &sport->port.state->xmit;
533 
534 	while (!uart_circ_empty(xmit) &&
535 		(readb(sport->port.membase + UARTTCFIFO) < sport->txfifo_size)) {
536 		writeb(xmit->buf[xmit->tail], sport->port.membase + UARTDR);
537 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
538 		sport->port.icount.tx++;
539 	}
540 
541 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
542 		uart_write_wakeup(&sport->port);
543 
544 	if (uart_circ_empty(xmit))
545 		lpuart_stop_tx(&sport->port);
546 }
547 
548 static inline void lpuart32_transmit_buffer(struct lpuart_port *sport)
549 {
550 	struct circ_buf *xmit = &sport->port.state->xmit;
551 	unsigned long txcnt;
552 
553 	txcnt = lpuart32_read(sport->port.membase + UARTWATER);
554 	txcnt = txcnt >> UARTWATER_TXCNT_OFF;
555 	txcnt &= UARTWATER_COUNT_MASK;
556 	while (!uart_circ_empty(xmit) && (txcnt < sport->txfifo_size)) {
557 		lpuart32_write(xmit->buf[xmit->tail], sport->port.membase + UARTDATA);
558 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
559 		sport->port.icount.tx++;
560 		txcnt = lpuart32_read(sport->port.membase + UARTWATER);
561 		txcnt = txcnt >> UARTWATER_TXCNT_OFF;
562 		txcnt &= UARTWATER_COUNT_MASK;
563 	}
564 
565 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
566 		uart_write_wakeup(&sport->port);
567 
568 	if (uart_circ_empty(xmit))
569 		lpuart32_stop_tx(&sport->port);
570 }
571 
572 static void lpuart_start_tx(struct uart_port *port)
573 {
574 	struct lpuart_port *sport = container_of(port,
575 			struct lpuart_port, port);
576 	struct circ_buf *xmit = &sport->port.state->xmit;
577 	unsigned char temp;
578 
579 	temp = readb(port->membase + UARTCR2);
580 	writeb(temp | UARTCR2_TIE, port->membase + UARTCR2);
581 
582 	if (sport->lpuart_dma_tx_use) {
583 		if (!uart_circ_empty(xmit) && !sport->dma_tx_in_progress)
584 			lpuart_prepare_tx(sport);
585 	} else {
586 		if (readb(port->membase + UARTSR1) & UARTSR1_TDRE)
587 			lpuart_transmit_buffer(sport);
588 	}
589 }
590 
591 static void lpuart32_start_tx(struct uart_port *port)
592 {
593 	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
594 	unsigned long temp;
595 
596 	temp = lpuart32_read(port->membase + UARTCTRL);
597 	lpuart32_write(temp | UARTCTRL_TIE, port->membase + UARTCTRL);
598 
599 	if (lpuart32_read(port->membase + UARTSTAT) & UARTSTAT_TDRE)
600 		lpuart32_transmit_buffer(sport);
601 }
602 
603 static irqreturn_t lpuart_txint(int irq, void *dev_id)
604 {
605 	struct lpuart_port *sport = dev_id;
606 	struct circ_buf *xmit = &sport->port.state->xmit;
607 	unsigned long flags;
608 
609 	spin_lock_irqsave(&sport->port.lock, flags);
610 	if (sport->port.x_char) {
611 		if (sport->lpuart32)
612 			lpuart32_write(sport->port.x_char, sport->port.membase + UARTDATA);
613 		else
614 			writeb(sport->port.x_char, sport->port.membase + UARTDR);
615 		goto out;
616 	}
617 
618 	if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
619 		if (sport->lpuart32)
620 			lpuart32_stop_tx(&sport->port);
621 		else
622 			lpuart_stop_tx(&sport->port);
623 		goto out;
624 	}
625 
626 	if (sport->lpuart32)
627 		lpuart32_transmit_buffer(sport);
628 	else
629 		lpuart_transmit_buffer(sport);
630 
631 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
632 		uart_write_wakeup(&sport->port);
633 
634 out:
635 	spin_unlock_irqrestore(&sport->port.lock, flags);
636 	return IRQ_HANDLED;
637 }
638 
639 static irqreturn_t lpuart_rxint(int irq, void *dev_id)
640 {
641 	struct lpuart_port *sport = dev_id;
642 	unsigned int flg, ignored = 0;
643 	struct tty_port *port = &sport->port.state->port;
644 	unsigned long flags;
645 	unsigned char rx, sr;
646 
647 	spin_lock_irqsave(&sport->port.lock, flags);
648 
649 	while (!(readb(sport->port.membase + UARTSFIFO) & UARTSFIFO_RXEMPT)) {
650 		flg = TTY_NORMAL;
651 		sport->port.icount.rx++;
652 		/*
653 		 * to clear the FE, OR, NF, FE, PE flags,
654 		 * read SR1 then read DR
655 		 */
656 		sr = readb(sport->port.membase + UARTSR1);
657 		rx = readb(sport->port.membase + UARTDR);
658 
659 		if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx))
660 			continue;
661 
662 		if (sr & (UARTSR1_PE | UARTSR1_OR | UARTSR1_FE)) {
663 			if (sr & UARTSR1_PE)
664 				sport->port.icount.parity++;
665 			else if (sr & UARTSR1_FE)
666 				sport->port.icount.frame++;
667 
668 			if (sr & UARTSR1_OR)
669 				sport->port.icount.overrun++;
670 
671 			if (sr & sport->port.ignore_status_mask) {
672 				if (++ignored > 100)
673 					goto out;
674 				continue;
675 			}
676 
677 			sr &= sport->port.read_status_mask;
678 
679 			if (sr & UARTSR1_PE)
680 				flg = TTY_PARITY;
681 			else if (sr & UARTSR1_FE)
682 				flg = TTY_FRAME;
683 
684 			if (sr & UARTSR1_OR)
685 				flg = TTY_OVERRUN;
686 
687 #ifdef SUPPORT_SYSRQ
688 			sport->port.sysrq = 0;
689 #endif
690 		}
691 
692 		tty_insert_flip_char(port, rx, flg);
693 	}
694 
695 out:
696 	spin_unlock_irqrestore(&sport->port.lock, flags);
697 
698 	tty_flip_buffer_push(port);
699 	return IRQ_HANDLED;
700 }
701 
702 static irqreturn_t lpuart32_rxint(int irq, void *dev_id)
703 {
704 	struct lpuart_port *sport = dev_id;
705 	unsigned int flg, ignored = 0;
706 	struct tty_port *port = &sport->port.state->port;
707 	unsigned long flags;
708 	unsigned long rx, sr;
709 
710 	spin_lock_irqsave(&sport->port.lock, flags);
711 
712 	while (!(lpuart32_read(sport->port.membase + UARTFIFO) & UARTFIFO_RXEMPT)) {
713 		flg = TTY_NORMAL;
714 		sport->port.icount.rx++;
715 		/*
716 		 * to clear the FE, OR, NF, FE, PE flags,
717 		 * read STAT then read DATA reg
718 		 */
719 		sr = lpuart32_read(sport->port.membase + UARTSTAT);
720 		rx = lpuart32_read(sport->port.membase + UARTDATA);
721 		rx &= 0x3ff;
722 
723 		if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx))
724 			continue;
725 
726 		if (sr & (UARTSTAT_PE | UARTSTAT_OR | UARTSTAT_FE)) {
727 			if (sr & UARTSTAT_PE)
728 				sport->port.icount.parity++;
729 			else if (sr & UARTSTAT_FE)
730 				sport->port.icount.frame++;
731 
732 			if (sr & UARTSTAT_OR)
733 				sport->port.icount.overrun++;
734 
735 			if (sr & sport->port.ignore_status_mask) {
736 				if (++ignored > 100)
737 					goto out;
738 				continue;
739 			}
740 
741 			sr &= sport->port.read_status_mask;
742 
743 			if (sr & UARTSTAT_PE)
744 				flg = TTY_PARITY;
745 			else if (sr & UARTSTAT_FE)
746 				flg = TTY_FRAME;
747 
748 			if (sr & UARTSTAT_OR)
749 				flg = TTY_OVERRUN;
750 
751 #ifdef SUPPORT_SYSRQ
752 			sport->port.sysrq = 0;
753 #endif
754 		}
755 
756 		tty_insert_flip_char(port, rx, flg);
757 	}
758 
759 out:
760 	spin_unlock_irqrestore(&sport->port.lock, flags);
761 
762 	tty_flip_buffer_push(port);
763 	return IRQ_HANDLED;
764 }
765 
766 static irqreturn_t lpuart_int(int irq, void *dev_id)
767 {
768 	struct lpuart_port *sport = dev_id;
769 	unsigned char sts, crdma;
770 
771 	sts = readb(sport->port.membase + UARTSR1);
772 	crdma = readb(sport->port.membase + UARTCR5);
773 
774 	if (sts & UARTSR1_RDRF && !(crdma & UARTCR5_RDMAS)) {
775 		if (sport->lpuart_dma_rx_use)
776 			lpuart_prepare_rx(sport);
777 		else
778 			lpuart_rxint(irq, dev_id);
779 	}
780 	if (sts & UARTSR1_TDRE && !(crdma & UARTCR5_TDMAS)) {
781 		if (sport->lpuart_dma_tx_use)
782 			lpuart_pio_tx(sport);
783 		else
784 			lpuart_txint(irq, dev_id);
785 	}
786 
787 	return IRQ_HANDLED;
788 }
789 
790 static irqreturn_t lpuart32_int(int irq, void *dev_id)
791 {
792 	struct lpuart_port *sport = dev_id;
793 	unsigned long sts, rxcount;
794 
795 	sts = lpuart32_read(sport->port.membase + UARTSTAT);
796 	rxcount = lpuart32_read(sport->port.membase + UARTWATER);
797 	rxcount = rxcount >> UARTWATER_RXCNT_OFF;
798 
799 	if (sts & UARTSTAT_RDRF || rxcount > 0)
800 		lpuart32_rxint(irq, dev_id);
801 
802 	if ((sts & UARTSTAT_TDRE) &&
803 		!(lpuart32_read(sport->port.membase + UARTBAUD) & UARTBAUD_TDMAE))
804 		lpuart_txint(irq, dev_id);
805 
806 	lpuart32_write(sts, sport->port.membase + UARTSTAT);
807 	return IRQ_HANDLED;
808 }
809 
810 /* return TIOCSER_TEMT when transmitter is not busy */
811 static unsigned int lpuart_tx_empty(struct uart_port *port)
812 {
813 	return (readb(port->membase + UARTSR1) & UARTSR1_TC) ?
814 		TIOCSER_TEMT : 0;
815 }
816 
817 static unsigned int lpuart32_tx_empty(struct uart_port *port)
818 {
819 	return (lpuart32_read(port->membase + UARTSTAT) & UARTSTAT_TC) ?
820 		TIOCSER_TEMT : 0;
821 }
822 
823 static unsigned int lpuart_get_mctrl(struct uart_port *port)
824 {
825 	unsigned int temp = 0;
826 	unsigned char reg;
827 
828 	reg = readb(port->membase + UARTMODEM);
829 	if (reg & UARTMODEM_TXCTSE)
830 		temp |= TIOCM_CTS;
831 
832 	if (reg & UARTMODEM_RXRTSE)
833 		temp |= TIOCM_RTS;
834 
835 	return temp;
836 }
837 
838 static unsigned int lpuart32_get_mctrl(struct uart_port *port)
839 {
840 	unsigned int temp = 0;
841 	unsigned long reg;
842 
843 	reg = lpuart32_read(port->membase + UARTMODIR);
844 	if (reg & UARTMODIR_TXCTSE)
845 		temp |= TIOCM_CTS;
846 
847 	if (reg & UARTMODIR_RXRTSE)
848 		temp |= TIOCM_RTS;
849 
850 	return temp;
851 }
852 
853 static void lpuart_set_mctrl(struct uart_port *port, unsigned int mctrl)
854 {
855 	unsigned char temp;
856 
857 	temp = readb(port->membase + UARTMODEM) &
858 			~(UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
859 
860 	if (mctrl & TIOCM_RTS)
861 		temp |= UARTMODEM_RXRTSE;
862 
863 	if (mctrl & TIOCM_CTS)
864 		temp |= UARTMODEM_TXCTSE;
865 
866 	writeb(temp, port->membase + UARTMODEM);
867 }
868 
869 static void lpuart32_set_mctrl(struct uart_port *port, unsigned int mctrl)
870 {
871 	unsigned long temp;
872 
873 	temp = lpuart32_read(port->membase + UARTMODIR) &
874 			~(UARTMODIR_RXRTSE | UARTMODIR_TXCTSE);
875 
876 	if (mctrl & TIOCM_RTS)
877 		temp |= UARTMODIR_RXRTSE;
878 
879 	if (mctrl & TIOCM_CTS)
880 		temp |= UARTMODIR_TXCTSE;
881 
882 	lpuart32_write(temp, port->membase + UARTMODIR);
883 }
884 
885 static void lpuart_break_ctl(struct uart_port *port, int break_state)
886 {
887 	unsigned char temp;
888 
889 	temp = readb(port->membase + UARTCR2) & ~UARTCR2_SBK;
890 
891 	if (break_state != 0)
892 		temp |= UARTCR2_SBK;
893 
894 	writeb(temp, port->membase + UARTCR2);
895 }
896 
897 static void lpuart32_break_ctl(struct uart_port *port, int break_state)
898 {
899 	unsigned long temp;
900 
901 	temp = lpuart32_read(port->membase + UARTCTRL) & ~UARTCTRL_SBK;
902 
903 	if (break_state != 0)
904 		temp |= UARTCTRL_SBK;
905 
906 	lpuart32_write(temp, port->membase + UARTCTRL);
907 }
908 
909 static void lpuart_setup_watermark(struct lpuart_port *sport)
910 {
911 	unsigned char val, cr2;
912 	unsigned char cr2_saved;
913 
914 	cr2 = readb(sport->port.membase + UARTCR2);
915 	cr2_saved = cr2;
916 	cr2 &= ~(UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_TE |
917 			UARTCR2_RIE | UARTCR2_RE);
918 	writeb(cr2, sport->port.membase + UARTCR2);
919 
920 	val = readb(sport->port.membase + UARTPFIFO);
921 	writeb(val | UARTPFIFO_TXFE | UARTPFIFO_RXFE,
922 			sport->port.membase + UARTPFIFO);
923 
924 	/* flush Tx and Rx FIFO */
925 	writeb(UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH,
926 			sport->port.membase + UARTCFIFO);
927 
928 	writeb(0, sport->port.membase + UARTTWFIFO);
929 	writeb(1, sport->port.membase + UARTRWFIFO);
930 
931 	/* Restore cr2 */
932 	writeb(cr2_saved, sport->port.membase + UARTCR2);
933 }
934 
935 static void lpuart32_setup_watermark(struct lpuart_port *sport)
936 {
937 	unsigned long val, ctrl;
938 	unsigned long ctrl_saved;
939 
940 	ctrl = lpuart32_read(sport->port.membase + UARTCTRL);
941 	ctrl_saved = ctrl;
942 	ctrl &= ~(UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_TE |
943 			UARTCTRL_RIE | UARTCTRL_RE);
944 	lpuart32_write(ctrl, sport->port.membase + UARTCTRL);
945 
946 	/* enable FIFO mode */
947 	val = lpuart32_read(sport->port.membase + UARTFIFO);
948 	val |= UARTFIFO_TXFE | UARTFIFO_RXFE;
949 	val |= UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH;
950 	lpuart32_write(val, sport->port.membase + UARTFIFO);
951 
952 	/* set the watermark */
953 	val = (0x1 << UARTWATER_RXWATER_OFF) | (0x0 << UARTWATER_TXWATER_OFF);
954 	lpuart32_write(val, sport->port.membase + UARTWATER);
955 
956 	/* Restore cr2 */
957 	lpuart32_write(ctrl_saved, sport->port.membase + UARTCTRL);
958 }
959 
960 static int lpuart_dma_tx_request(struct uart_port *port)
961 {
962 	struct lpuart_port *sport = container_of(port,
963 					struct lpuart_port, port);
964 	struct dma_slave_config dma_tx_sconfig;
965 	dma_addr_t dma_bus;
966 	unsigned char *dma_buf;
967 	int ret;
968 
969 	dma_bus = dma_map_single(sport->dma_tx_chan->device->dev,
970 				sport->port.state->xmit.buf,
971 				UART_XMIT_SIZE, DMA_TO_DEVICE);
972 
973 	if (dma_mapping_error(sport->dma_tx_chan->device->dev, dma_bus)) {
974 		dev_err(sport->port.dev, "dma_map_single tx failed\n");
975 		return -ENOMEM;
976 	}
977 
978 	dma_buf = sport->port.state->xmit.buf;
979 	dma_tx_sconfig.dst_addr = sport->port.mapbase + UARTDR;
980 	dma_tx_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
981 	dma_tx_sconfig.dst_maxburst = sport->txfifo_size;
982 	dma_tx_sconfig.direction = DMA_MEM_TO_DEV;
983 	ret = dmaengine_slave_config(sport->dma_tx_chan, &dma_tx_sconfig);
984 
985 	if (ret < 0) {
986 		dev_err(sport->port.dev,
987 				"Dma slave config failed, err = %d\n", ret);
988 		return ret;
989 	}
990 
991 	sport->dma_tx_buf_virt = dma_buf;
992 	sport->dma_tx_buf_bus = dma_bus;
993 	sport->dma_tx_in_progress = 0;
994 
995 	return 0;
996 }
997 
998 static int lpuart_dma_rx_request(struct uart_port *port)
999 {
1000 	struct lpuart_port *sport = container_of(port,
1001 					struct lpuart_port, port);
1002 	struct dma_slave_config dma_rx_sconfig;
1003 	dma_addr_t dma_bus;
1004 	unsigned char *dma_buf;
1005 	int ret;
1006 
1007 	dma_buf = devm_kzalloc(sport->port.dev,
1008 				FSL_UART_RX_DMA_BUFFER_SIZE, GFP_KERNEL);
1009 
1010 	if (!dma_buf) {
1011 		dev_err(sport->port.dev, "Dma rx alloc failed\n");
1012 		return -ENOMEM;
1013 	}
1014 
1015 	dma_bus = dma_map_single(sport->dma_rx_chan->device->dev, dma_buf,
1016 				FSL_UART_RX_DMA_BUFFER_SIZE, DMA_FROM_DEVICE);
1017 
1018 	if (dma_mapping_error(sport->dma_rx_chan->device->dev, dma_bus)) {
1019 		dev_err(sport->port.dev, "dma_map_single rx failed\n");
1020 		return -ENOMEM;
1021 	}
1022 
1023 	dma_rx_sconfig.src_addr = sport->port.mapbase + UARTDR;
1024 	dma_rx_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1025 	dma_rx_sconfig.src_maxburst = 1;
1026 	dma_rx_sconfig.direction = DMA_DEV_TO_MEM;
1027 	ret = dmaengine_slave_config(sport->dma_rx_chan, &dma_rx_sconfig);
1028 
1029 	if (ret < 0) {
1030 		dev_err(sport->port.dev,
1031 				"Dma slave config failed, err = %d\n", ret);
1032 		return ret;
1033 	}
1034 
1035 	sport->dma_rx_buf_virt = dma_buf;
1036 	sport->dma_rx_buf_bus = dma_bus;
1037 	sport->dma_rx_in_progress = 0;
1038 
1039 	return 0;
1040 }
1041 
1042 static void lpuart_dma_tx_free(struct uart_port *port)
1043 {
1044 	struct lpuart_port *sport = container_of(port,
1045 					struct lpuart_port, port);
1046 
1047 	dma_unmap_single(sport->port.dev, sport->dma_tx_buf_bus,
1048 			UART_XMIT_SIZE, DMA_TO_DEVICE);
1049 
1050 	sport->dma_tx_buf_bus = 0;
1051 	sport->dma_tx_buf_virt = NULL;
1052 }
1053 
1054 static void lpuart_dma_rx_free(struct uart_port *port)
1055 {
1056 	struct lpuart_port *sport = container_of(port,
1057 					struct lpuart_port, port);
1058 
1059 	dma_unmap_single(sport->port.dev, sport->dma_rx_buf_bus,
1060 			FSL_UART_RX_DMA_BUFFER_SIZE, DMA_FROM_DEVICE);
1061 
1062 	sport->dma_rx_buf_bus = 0;
1063 	sport->dma_rx_buf_virt = NULL;
1064 }
1065 
1066 static int lpuart_startup(struct uart_port *port)
1067 {
1068 	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1069 	int ret;
1070 	unsigned long flags;
1071 	unsigned char temp;
1072 
1073 	/* determine FIFO size and enable FIFO mode */
1074 	temp = readb(sport->port.membase + UARTPFIFO);
1075 
1076 	sport->txfifo_size = 0x1 << (((temp >> UARTPFIFO_TXSIZE_OFF) &
1077 		UARTPFIFO_FIFOSIZE_MASK) + 1);
1078 
1079 	sport->rxfifo_size = 0x1 << (((temp >> UARTPFIFO_RXSIZE_OFF) &
1080 		UARTPFIFO_FIFOSIZE_MASK) + 1);
1081 
1082 	if (sport->dma_rx_chan && !lpuart_dma_rx_request(port)) {
1083 		sport->lpuart_dma_rx_use = true;
1084 		setup_timer(&sport->lpuart_timer, lpuart_timer_func,
1085 			    (unsigned long)sport);
1086 	} else
1087 		sport->lpuart_dma_rx_use = false;
1088 
1089 
1090 	if (sport->dma_tx_chan && !lpuart_dma_tx_request(port)) {
1091 		sport->lpuart_dma_tx_use = true;
1092 		temp = readb(port->membase + UARTCR5);
1093 		temp &= ~UARTCR5_RDMAS;
1094 		writeb(temp | UARTCR5_TDMAS, port->membase + UARTCR5);
1095 	} else
1096 		sport->lpuart_dma_tx_use = false;
1097 
1098 	ret = devm_request_irq(port->dev, port->irq, lpuart_int, 0,
1099 				DRIVER_NAME, sport);
1100 	if (ret)
1101 		return ret;
1102 
1103 	spin_lock_irqsave(&sport->port.lock, flags);
1104 
1105 	lpuart_setup_watermark(sport);
1106 
1107 	temp = readb(sport->port.membase + UARTCR2);
1108 	temp |= (UARTCR2_RIE | UARTCR2_TIE | UARTCR2_RE | UARTCR2_TE);
1109 	writeb(temp, sport->port.membase + UARTCR2);
1110 
1111 	spin_unlock_irqrestore(&sport->port.lock, flags);
1112 	return 0;
1113 }
1114 
1115 static int lpuart32_startup(struct uart_port *port)
1116 {
1117 	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1118 	int ret;
1119 	unsigned long flags;
1120 	unsigned long temp;
1121 
1122 	/* determine FIFO size */
1123 	temp = lpuart32_read(sport->port.membase + UARTFIFO);
1124 
1125 	sport->txfifo_size = 0x1 << (((temp >> UARTFIFO_TXSIZE_OFF) &
1126 		UARTFIFO_FIFOSIZE_MASK) - 1);
1127 
1128 	sport->rxfifo_size = 0x1 << (((temp >> UARTFIFO_RXSIZE_OFF) &
1129 		UARTFIFO_FIFOSIZE_MASK) - 1);
1130 
1131 	ret = devm_request_irq(port->dev, port->irq, lpuart32_int, 0,
1132 				DRIVER_NAME, sport);
1133 	if (ret)
1134 		return ret;
1135 
1136 	spin_lock_irqsave(&sport->port.lock, flags);
1137 
1138 	lpuart32_setup_watermark(sport);
1139 
1140 	temp = lpuart32_read(sport->port.membase + UARTCTRL);
1141 	temp |= (UARTCTRL_RIE | UARTCTRL_TIE | UARTCTRL_RE | UARTCTRL_TE);
1142 	temp |= UARTCTRL_ILIE;
1143 	lpuart32_write(temp, sport->port.membase + UARTCTRL);
1144 
1145 	spin_unlock_irqrestore(&sport->port.lock, flags);
1146 	return 0;
1147 }
1148 
1149 static void lpuart_shutdown(struct uart_port *port)
1150 {
1151 	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1152 	unsigned char temp;
1153 	unsigned long flags;
1154 
1155 	spin_lock_irqsave(&port->lock, flags);
1156 
1157 	/* disable Rx/Tx and interrupts */
1158 	temp = readb(port->membase + UARTCR2);
1159 	temp &= ~(UARTCR2_TE | UARTCR2_RE |
1160 			UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_RIE);
1161 	writeb(temp, port->membase + UARTCR2);
1162 
1163 	spin_unlock_irqrestore(&port->lock, flags);
1164 
1165 	devm_free_irq(port->dev, port->irq, sport);
1166 
1167 	if (sport->lpuart_dma_rx_use) {
1168 		lpuart_dma_rx_free(&sport->port);
1169 		del_timer_sync(&sport->lpuart_timer);
1170 	}
1171 
1172 	if (sport->lpuart_dma_tx_use)
1173 		lpuart_dma_tx_free(&sport->port);
1174 }
1175 
1176 static void lpuart32_shutdown(struct uart_port *port)
1177 {
1178 	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1179 	unsigned long temp;
1180 	unsigned long flags;
1181 
1182 	spin_lock_irqsave(&port->lock, flags);
1183 
1184 	/* disable Rx/Tx and interrupts */
1185 	temp = lpuart32_read(port->membase + UARTCTRL);
1186 	temp &= ~(UARTCTRL_TE | UARTCTRL_RE |
1187 			UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_RIE);
1188 	lpuart32_write(temp, port->membase + UARTCTRL);
1189 
1190 	spin_unlock_irqrestore(&port->lock, flags);
1191 
1192 	devm_free_irq(port->dev, port->irq, sport);
1193 }
1194 
1195 static void
1196 lpuart_set_termios(struct uart_port *port, struct ktermios *termios,
1197 		   struct ktermios *old)
1198 {
1199 	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1200 	unsigned long flags;
1201 	unsigned char cr1, old_cr1, old_cr2, cr4, bdh, modem;
1202 	unsigned int  baud;
1203 	unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
1204 	unsigned int sbr, brfa;
1205 
1206 	cr1 = old_cr1 = readb(sport->port.membase + UARTCR1);
1207 	old_cr2 = readb(sport->port.membase + UARTCR2);
1208 	cr4 = readb(sport->port.membase + UARTCR4);
1209 	bdh = readb(sport->port.membase + UARTBDH);
1210 	modem = readb(sport->port.membase + UARTMODEM);
1211 	/*
1212 	 * only support CS8 and CS7, and for CS7 must enable PE.
1213 	 * supported mode:
1214 	 *  - (7,e/o,1)
1215 	 *  - (8,n,1)
1216 	 *  - (8,m/s,1)
1217 	 *  - (8,e/o,1)
1218 	 */
1219 	while ((termios->c_cflag & CSIZE) != CS8 &&
1220 		(termios->c_cflag & CSIZE) != CS7) {
1221 		termios->c_cflag &= ~CSIZE;
1222 		termios->c_cflag |= old_csize;
1223 		old_csize = CS8;
1224 	}
1225 
1226 	if ((termios->c_cflag & CSIZE) == CS8 ||
1227 		(termios->c_cflag & CSIZE) == CS7)
1228 		cr1 = old_cr1 & ~UARTCR1_M;
1229 
1230 	if (termios->c_cflag & CMSPAR) {
1231 		if ((termios->c_cflag & CSIZE) != CS8) {
1232 			termios->c_cflag &= ~CSIZE;
1233 			termios->c_cflag |= CS8;
1234 		}
1235 		cr1 |= UARTCR1_M;
1236 	}
1237 
1238 	if (termios->c_cflag & CRTSCTS) {
1239 		modem |= (UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1240 	} else {
1241 		termios->c_cflag &= ~CRTSCTS;
1242 		modem &= ~(UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1243 	}
1244 
1245 	if (termios->c_cflag & CSTOPB)
1246 		termios->c_cflag &= ~CSTOPB;
1247 
1248 	/* parity must be enabled when CS7 to match 8-bits format */
1249 	if ((termios->c_cflag & CSIZE) == CS7)
1250 		termios->c_cflag |= PARENB;
1251 
1252 	if ((termios->c_cflag & PARENB)) {
1253 		if (termios->c_cflag & CMSPAR) {
1254 			cr1 &= ~UARTCR1_PE;
1255 			cr1 |= UARTCR1_M;
1256 		} else {
1257 			cr1 |= UARTCR1_PE;
1258 			if ((termios->c_cflag & CSIZE) == CS8)
1259 				cr1 |= UARTCR1_M;
1260 			if (termios->c_cflag & PARODD)
1261 				cr1 |= UARTCR1_PT;
1262 			else
1263 				cr1 &= ~UARTCR1_PT;
1264 		}
1265 	}
1266 
1267 	/* ask the core to calculate the divisor */
1268 	baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
1269 
1270 	spin_lock_irqsave(&sport->port.lock, flags);
1271 
1272 	sport->port.read_status_mask = 0;
1273 	if (termios->c_iflag & INPCK)
1274 		sport->port.read_status_mask |=	(UARTSR1_FE | UARTSR1_PE);
1275 	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
1276 		sport->port.read_status_mask |= UARTSR1_FE;
1277 
1278 	/* characters to ignore */
1279 	sport->port.ignore_status_mask = 0;
1280 	if (termios->c_iflag & IGNPAR)
1281 		sport->port.ignore_status_mask |= UARTSR1_PE;
1282 	if (termios->c_iflag & IGNBRK) {
1283 		sport->port.ignore_status_mask |= UARTSR1_FE;
1284 		/*
1285 		 * if we're ignoring parity and break indicators,
1286 		 * ignore overruns too (for real raw support).
1287 		 */
1288 		if (termios->c_iflag & IGNPAR)
1289 			sport->port.ignore_status_mask |= UARTSR1_OR;
1290 	}
1291 
1292 	/* update the per-port timeout */
1293 	uart_update_timeout(port, termios->c_cflag, baud);
1294 
1295 	if (sport->lpuart_dma_rx_use) {
1296 		/* Calculate delay for 1.5 DMA buffers */
1297 		sport->dma_rx_timeout = (sport->port.timeout - HZ / 50) *
1298 					FSL_UART_RX_DMA_BUFFER_SIZE * 3 /
1299 					sport->rxfifo_size / 2;
1300 		dev_dbg(port->dev, "DMA Rx t-out %ums, tty t-out %u jiffies\n",
1301 			sport->dma_rx_timeout * 1000 / HZ, sport->port.timeout);
1302 		if (sport->dma_rx_timeout < msecs_to_jiffies(20))
1303 			sport->dma_rx_timeout = msecs_to_jiffies(20);
1304 	}
1305 
1306 	/* wait transmit engin complete */
1307 	while (!(readb(sport->port.membase + UARTSR1) & UARTSR1_TC))
1308 		barrier();
1309 
1310 	/* disable transmit and receive */
1311 	writeb(old_cr2 & ~(UARTCR2_TE | UARTCR2_RE),
1312 			sport->port.membase + UARTCR2);
1313 
1314 	sbr = sport->port.uartclk / (16 * baud);
1315 	brfa = ((sport->port.uartclk - (16 * sbr * baud)) * 2) / baud;
1316 	bdh &= ~UARTBDH_SBR_MASK;
1317 	bdh |= (sbr >> 8) & 0x1F;
1318 	cr4 &= ~UARTCR4_BRFA_MASK;
1319 	brfa &= UARTCR4_BRFA_MASK;
1320 	writeb(cr4 | brfa, sport->port.membase + UARTCR4);
1321 	writeb(bdh, sport->port.membase + UARTBDH);
1322 	writeb(sbr & 0xFF, sport->port.membase + UARTBDL);
1323 	writeb(cr1, sport->port.membase + UARTCR1);
1324 	writeb(modem, sport->port.membase + UARTMODEM);
1325 
1326 	/* restore control register */
1327 	writeb(old_cr2, sport->port.membase + UARTCR2);
1328 
1329 	spin_unlock_irqrestore(&sport->port.lock, flags);
1330 }
1331 
1332 static void
1333 lpuart32_set_termios(struct uart_port *port, struct ktermios *termios,
1334 		   struct ktermios *old)
1335 {
1336 	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1337 	unsigned long flags;
1338 	unsigned long ctrl, old_ctrl, bd, modem;
1339 	unsigned int  baud;
1340 	unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
1341 	unsigned int sbr;
1342 
1343 	ctrl = old_ctrl = lpuart32_read(sport->port.membase + UARTCTRL);
1344 	bd = lpuart32_read(sport->port.membase + UARTBAUD);
1345 	modem = lpuart32_read(sport->port.membase + UARTMODIR);
1346 	/*
1347 	 * only support CS8 and CS7, and for CS7 must enable PE.
1348 	 * supported mode:
1349 	 *  - (7,e/o,1)
1350 	 *  - (8,n,1)
1351 	 *  - (8,m/s,1)
1352 	 *  - (8,e/o,1)
1353 	 */
1354 	while ((termios->c_cflag & CSIZE) != CS8 &&
1355 		(termios->c_cflag & CSIZE) != CS7) {
1356 		termios->c_cflag &= ~CSIZE;
1357 		termios->c_cflag |= old_csize;
1358 		old_csize = CS8;
1359 	}
1360 
1361 	if ((termios->c_cflag & CSIZE) == CS8 ||
1362 		(termios->c_cflag & CSIZE) == CS7)
1363 		ctrl = old_ctrl & ~UARTCTRL_M;
1364 
1365 	if (termios->c_cflag & CMSPAR) {
1366 		if ((termios->c_cflag & CSIZE) != CS8) {
1367 			termios->c_cflag &= ~CSIZE;
1368 			termios->c_cflag |= CS8;
1369 		}
1370 		ctrl |= UARTCTRL_M;
1371 	}
1372 
1373 	if (termios->c_cflag & CRTSCTS) {
1374 		modem |= (UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1375 	} else {
1376 		termios->c_cflag &= ~CRTSCTS;
1377 		modem &= ~(UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1378 	}
1379 
1380 	if (termios->c_cflag & CSTOPB)
1381 		termios->c_cflag &= ~CSTOPB;
1382 
1383 	/* parity must be enabled when CS7 to match 8-bits format */
1384 	if ((termios->c_cflag & CSIZE) == CS7)
1385 		termios->c_cflag |= PARENB;
1386 
1387 	if ((termios->c_cflag & PARENB)) {
1388 		if (termios->c_cflag & CMSPAR) {
1389 			ctrl &= ~UARTCTRL_PE;
1390 			ctrl |= UARTCTRL_M;
1391 		} else {
1392 			ctrl |= UARTCR1_PE;
1393 			if ((termios->c_cflag & CSIZE) == CS8)
1394 				ctrl |= UARTCTRL_M;
1395 			if (termios->c_cflag & PARODD)
1396 				ctrl |= UARTCTRL_PT;
1397 			else
1398 				ctrl &= ~UARTCTRL_PT;
1399 		}
1400 	}
1401 
1402 	/* ask the core to calculate the divisor */
1403 	baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
1404 
1405 	spin_lock_irqsave(&sport->port.lock, flags);
1406 
1407 	sport->port.read_status_mask = 0;
1408 	if (termios->c_iflag & INPCK)
1409 		sport->port.read_status_mask |=	(UARTSTAT_FE | UARTSTAT_PE);
1410 	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
1411 		sport->port.read_status_mask |= UARTSTAT_FE;
1412 
1413 	/* characters to ignore */
1414 	sport->port.ignore_status_mask = 0;
1415 	if (termios->c_iflag & IGNPAR)
1416 		sport->port.ignore_status_mask |= UARTSTAT_PE;
1417 	if (termios->c_iflag & IGNBRK) {
1418 		sport->port.ignore_status_mask |= UARTSTAT_FE;
1419 		/*
1420 		 * if we're ignoring parity and break indicators,
1421 		 * ignore overruns too (for real raw support).
1422 		 */
1423 		if (termios->c_iflag & IGNPAR)
1424 			sport->port.ignore_status_mask |= UARTSTAT_OR;
1425 	}
1426 
1427 	/* update the per-port timeout */
1428 	uart_update_timeout(port, termios->c_cflag, baud);
1429 
1430 	/* wait transmit engin complete */
1431 	while (!(lpuart32_read(sport->port.membase + UARTSTAT) & UARTSTAT_TC))
1432 		barrier();
1433 
1434 	/* disable transmit and receive */
1435 	lpuart32_write(old_ctrl & ~(UARTCTRL_TE | UARTCTRL_RE),
1436 			sport->port.membase + UARTCTRL);
1437 
1438 	sbr = sport->port.uartclk / (16 * baud);
1439 	bd &= ~UARTBAUD_SBR_MASK;
1440 	bd |= sbr & UARTBAUD_SBR_MASK;
1441 	bd |= UARTBAUD_BOTHEDGE;
1442 	bd &= ~(UARTBAUD_TDMAE | UARTBAUD_RDMAE);
1443 	lpuart32_write(bd, sport->port.membase + UARTBAUD);
1444 	lpuart32_write(modem, sport->port.membase + UARTMODIR);
1445 	lpuart32_write(ctrl, sport->port.membase + UARTCTRL);
1446 	/* restore control register */
1447 
1448 	spin_unlock_irqrestore(&sport->port.lock, flags);
1449 }
1450 
1451 static const char *lpuart_type(struct uart_port *port)
1452 {
1453 	return "FSL_LPUART";
1454 }
1455 
1456 static void lpuart_release_port(struct uart_port *port)
1457 {
1458 	/* nothing to do */
1459 }
1460 
1461 static int lpuart_request_port(struct uart_port *port)
1462 {
1463 	return  0;
1464 }
1465 
1466 /* configure/autoconfigure the port */
1467 static void lpuart_config_port(struct uart_port *port, int flags)
1468 {
1469 	if (flags & UART_CONFIG_TYPE)
1470 		port->type = PORT_LPUART;
1471 }
1472 
1473 static int lpuart_verify_port(struct uart_port *port, struct serial_struct *ser)
1474 {
1475 	int ret = 0;
1476 
1477 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_LPUART)
1478 		ret = -EINVAL;
1479 	if (port->irq != ser->irq)
1480 		ret = -EINVAL;
1481 	if (ser->io_type != UPIO_MEM)
1482 		ret = -EINVAL;
1483 	if (port->uartclk / 16 != ser->baud_base)
1484 		ret = -EINVAL;
1485 	if (port->iobase != ser->port)
1486 		ret = -EINVAL;
1487 	if (ser->hub6 != 0)
1488 		ret = -EINVAL;
1489 	return ret;
1490 }
1491 
1492 static struct uart_ops lpuart_pops = {
1493 	.tx_empty	= lpuart_tx_empty,
1494 	.set_mctrl	= lpuart_set_mctrl,
1495 	.get_mctrl	= lpuart_get_mctrl,
1496 	.stop_tx	= lpuart_stop_tx,
1497 	.start_tx	= lpuart_start_tx,
1498 	.stop_rx	= lpuart_stop_rx,
1499 	.break_ctl	= lpuart_break_ctl,
1500 	.startup	= lpuart_startup,
1501 	.shutdown	= lpuart_shutdown,
1502 	.set_termios	= lpuart_set_termios,
1503 	.type		= lpuart_type,
1504 	.request_port	= lpuart_request_port,
1505 	.release_port	= lpuart_release_port,
1506 	.config_port	= lpuart_config_port,
1507 	.verify_port	= lpuart_verify_port,
1508 	.flush_buffer	= lpuart_flush_buffer,
1509 };
1510 
1511 static struct uart_ops lpuart32_pops = {
1512 	.tx_empty	= lpuart32_tx_empty,
1513 	.set_mctrl	= lpuart32_set_mctrl,
1514 	.get_mctrl	= lpuart32_get_mctrl,
1515 	.stop_tx	= lpuart32_stop_tx,
1516 	.start_tx	= lpuart32_start_tx,
1517 	.stop_rx	= lpuart32_stop_rx,
1518 	.break_ctl	= lpuart32_break_ctl,
1519 	.startup	= lpuart32_startup,
1520 	.shutdown	= lpuart32_shutdown,
1521 	.set_termios	= lpuart32_set_termios,
1522 	.type		= lpuart_type,
1523 	.request_port	= lpuart_request_port,
1524 	.release_port	= lpuart_release_port,
1525 	.config_port	= lpuart_config_port,
1526 	.verify_port	= lpuart_verify_port,
1527 	.flush_buffer	= lpuart_flush_buffer,
1528 };
1529 
1530 static struct lpuart_port *lpuart_ports[UART_NR];
1531 
1532 #ifdef CONFIG_SERIAL_FSL_LPUART_CONSOLE
1533 static void lpuart_console_putchar(struct uart_port *port, int ch)
1534 {
1535 	while (!(readb(port->membase + UARTSR1) & UARTSR1_TDRE))
1536 		barrier();
1537 
1538 	writeb(ch, port->membase + UARTDR);
1539 }
1540 
1541 static void lpuart32_console_putchar(struct uart_port *port, int ch)
1542 {
1543 	while (!(lpuart32_read(port->membase + UARTSTAT) & UARTSTAT_TDRE))
1544 		barrier();
1545 
1546 	lpuart32_write(ch, port->membase + UARTDATA);
1547 }
1548 
1549 static void
1550 lpuart_console_write(struct console *co, const char *s, unsigned int count)
1551 {
1552 	struct lpuart_port *sport = lpuart_ports[co->index];
1553 	unsigned char  old_cr2, cr2;
1554 
1555 	/* first save CR2 and then disable interrupts */
1556 	cr2 = old_cr2 = readb(sport->port.membase + UARTCR2);
1557 	cr2 |= (UARTCR2_TE |  UARTCR2_RE);
1558 	cr2 &= ~(UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_RIE);
1559 	writeb(cr2, sport->port.membase + UARTCR2);
1560 
1561 	uart_console_write(&sport->port, s, count, lpuart_console_putchar);
1562 
1563 	/* wait for transmitter finish complete and restore CR2 */
1564 	while (!(readb(sport->port.membase + UARTSR1) & UARTSR1_TC))
1565 		barrier();
1566 
1567 	writeb(old_cr2, sport->port.membase + UARTCR2);
1568 }
1569 
1570 static void
1571 lpuart32_console_write(struct console *co, const char *s, unsigned int count)
1572 {
1573 	struct lpuart_port *sport = lpuart_ports[co->index];
1574 	unsigned long  old_cr, cr;
1575 
1576 	/* first save CR2 and then disable interrupts */
1577 	cr = old_cr = lpuart32_read(sport->port.membase + UARTCTRL);
1578 	cr |= (UARTCTRL_TE |  UARTCTRL_RE);
1579 	cr &= ~(UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_RIE);
1580 	lpuart32_write(cr, sport->port.membase + UARTCTRL);
1581 
1582 	uart_console_write(&sport->port, s, count, lpuart32_console_putchar);
1583 
1584 	/* wait for transmitter finish complete and restore CR2 */
1585 	while (!(lpuart32_read(sport->port.membase + UARTSTAT) & UARTSTAT_TC))
1586 		barrier();
1587 
1588 	lpuart32_write(old_cr, sport->port.membase + UARTCTRL);
1589 }
1590 
1591 /*
1592  * if the port was already initialised (eg, by a boot loader),
1593  * try to determine the current setup.
1594  */
1595 static void __init
1596 lpuart_console_get_options(struct lpuart_port *sport, int *baud,
1597 			   int *parity, int *bits)
1598 {
1599 	unsigned char cr, bdh, bdl, brfa;
1600 	unsigned int sbr, uartclk, baud_raw;
1601 
1602 	cr = readb(sport->port.membase + UARTCR2);
1603 	cr &= UARTCR2_TE | UARTCR2_RE;
1604 	if (!cr)
1605 		return;
1606 
1607 	/* ok, the port was enabled */
1608 
1609 	cr = readb(sport->port.membase + UARTCR1);
1610 
1611 	*parity = 'n';
1612 	if (cr & UARTCR1_PE) {
1613 		if (cr & UARTCR1_PT)
1614 			*parity = 'o';
1615 		else
1616 			*parity = 'e';
1617 	}
1618 
1619 	if (cr & UARTCR1_M)
1620 		*bits = 9;
1621 	else
1622 		*bits = 8;
1623 
1624 	bdh = readb(sport->port.membase + UARTBDH);
1625 	bdh &= UARTBDH_SBR_MASK;
1626 	bdl = readb(sport->port.membase + UARTBDL);
1627 	sbr = bdh;
1628 	sbr <<= 8;
1629 	sbr |= bdl;
1630 	brfa = readb(sport->port.membase + UARTCR4);
1631 	brfa &= UARTCR4_BRFA_MASK;
1632 
1633 	uartclk = clk_get_rate(sport->clk);
1634 	/*
1635 	 * baud = mod_clk/(16*(sbr[13]+(brfa)/32)
1636 	 */
1637 	baud_raw = uartclk / (16 * (sbr + brfa / 32));
1638 
1639 	if (*baud != baud_raw)
1640 		printk(KERN_INFO "Serial: Console lpuart rounded baud rate"
1641 				"from %d to %d\n", baud_raw, *baud);
1642 }
1643 
1644 static void __init
1645 lpuart32_console_get_options(struct lpuart_port *sport, int *baud,
1646 			   int *parity, int *bits)
1647 {
1648 	unsigned long cr, bd;
1649 	unsigned int sbr, uartclk, baud_raw;
1650 
1651 	cr = lpuart32_read(sport->port.membase + UARTCTRL);
1652 	cr &= UARTCTRL_TE | UARTCTRL_RE;
1653 	if (!cr)
1654 		return;
1655 
1656 	/* ok, the port was enabled */
1657 
1658 	cr = lpuart32_read(sport->port.membase + UARTCTRL);
1659 
1660 	*parity = 'n';
1661 	if (cr & UARTCTRL_PE) {
1662 		if (cr & UARTCTRL_PT)
1663 			*parity = 'o';
1664 		else
1665 			*parity = 'e';
1666 	}
1667 
1668 	if (cr & UARTCTRL_M)
1669 		*bits = 9;
1670 	else
1671 		*bits = 8;
1672 
1673 	bd = lpuart32_read(sport->port.membase + UARTBAUD);
1674 	bd &= UARTBAUD_SBR_MASK;
1675 	sbr = bd;
1676 	uartclk = clk_get_rate(sport->clk);
1677 	/*
1678 	 * baud = mod_clk/(16*(sbr[13]+(brfa)/32)
1679 	 */
1680 	baud_raw = uartclk / (16 * sbr);
1681 
1682 	if (*baud != baud_raw)
1683 		printk(KERN_INFO "Serial: Console lpuart rounded baud rate"
1684 				"from %d to %d\n", baud_raw, *baud);
1685 }
1686 
1687 static int __init lpuart_console_setup(struct console *co, char *options)
1688 {
1689 	struct lpuart_port *sport;
1690 	int baud = 115200;
1691 	int bits = 8;
1692 	int parity = 'n';
1693 	int flow = 'n';
1694 
1695 	/*
1696 	 * check whether an invalid uart number has been specified, and
1697 	 * if so, search for the first available port that does have
1698 	 * console support.
1699 	 */
1700 	if (co->index == -1 || co->index >= ARRAY_SIZE(lpuart_ports))
1701 		co->index = 0;
1702 
1703 	sport = lpuart_ports[co->index];
1704 	if (sport == NULL)
1705 		return -ENODEV;
1706 
1707 	if (options)
1708 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1709 	else
1710 		if (sport->lpuart32)
1711 			lpuart32_console_get_options(sport, &baud, &parity, &bits);
1712 		else
1713 			lpuart_console_get_options(sport, &baud, &parity, &bits);
1714 
1715 	if (sport->lpuart32)
1716 		lpuart32_setup_watermark(sport);
1717 	else
1718 		lpuart_setup_watermark(sport);
1719 
1720 	return uart_set_options(&sport->port, co, baud, parity, bits, flow);
1721 }
1722 
1723 static struct uart_driver lpuart_reg;
1724 static struct console lpuart_console = {
1725 	.name		= DEV_NAME,
1726 	.write		= lpuart_console_write,
1727 	.device		= uart_console_device,
1728 	.setup		= lpuart_console_setup,
1729 	.flags		= CON_PRINTBUFFER,
1730 	.index		= -1,
1731 	.data		= &lpuart_reg,
1732 };
1733 
1734 static struct console lpuart32_console = {
1735 	.name		= DEV_NAME,
1736 	.write		= lpuart32_console_write,
1737 	.device		= uart_console_device,
1738 	.setup		= lpuart_console_setup,
1739 	.flags		= CON_PRINTBUFFER,
1740 	.index		= -1,
1741 	.data		= &lpuart_reg,
1742 };
1743 
1744 #define LPUART_CONSOLE	(&lpuart_console)
1745 #define LPUART32_CONSOLE	(&lpuart32_console)
1746 #else
1747 #define LPUART_CONSOLE	NULL
1748 #define LPUART32_CONSOLE	NULL
1749 #endif
1750 
1751 static struct uart_driver lpuart_reg = {
1752 	.owner		= THIS_MODULE,
1753 	.driver_name	= DRIVER_NAME,
1754 	.dev_name	= DEV_NAME,
1755 	.nr		= ARRAY_SIZE(lpuart_ports),
1756 	.cons		= LPUART_CONSOLE,
1757 };
1758 
1759 static int lpuart_probe(struct platform_device *pdev)
1760 {
1761 	struct device_node *np = pdev->dev.of_node;
1762 	struct lpuart_port *sport;
1763 	struct resource *res;
1764 	int ret;
1765 
1766 	sport = devm_kzalloc(&pdev->dev, sizeof(*sport), GFP_KERNEL);
1767 	if (!sport)
1768 		return -ENOMEM;
1769 
1770 	pdev->dev.coherent_dma_mask = 0;
1771 
1772 	ret = of_alias_get_id(np, "serial");
1773 	if (ret < 0) {
1774 		dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
1775 		return ret;
1776 	}
1777 	sport->port.line = ret;
1778 	sport->lpuart32 = of_device_is_compatible(np, "fsl,ls1021a-lpuart");
1779 
1780 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1781 	sport->port.membase = devm_ioremap_resource(&pdev->dev, res);
1782 	if (IS_ERR(sport->port.membase))
1783 		return PTR_ERR(sport->port.membase);
1784 
1785 	sport->port.mapbase = res->start;
1786 	sport->port.dev = &pdev->dev;
1787 	sport->port.type = PORT_LPUART;
1788 	sport->port.iotype = UPIO_MEM;
1789 	sport->port.irq = platform_get_irq(pdev, 0);
1790 	if (sport->lpuart32)
1791 		sport->port.ops = &lpuart32_pops;
1792 	else
1793 		sport->port.ops = &lpuart_pops;
1794 	sport->port.flags = UPF_BOOT_AUTOCONF;
1795 
1796 	sport->clk = devm_clk_get(&pdev->dev, "ipg");
1797 	if (IS_ERR(sport->clk)) {
1798 		ret = PTR_ERR(sport->clk);
1799 		dev_err(&pdev->dev, "failed to get uart clk: %d\n", ret);
1800 		return ret;
1801 	}
1802 
1803 	ret = clk_prepare_enable(sport->clk);
1804 	if (ret) {
1805 		dev_err(&pdev->dev, "failed to enable uart clk: %d\n", ret);
1806 		return ret;
1807 	}
1808 
1809 	sport->port.uartclk = clk_get_rate(sport->clk);
1810 
1811 	lpuart_ports[sport->port.line] = sport;
1812 
1813 	platform_set_drvdata(pdev, &sport->port);
1814 
1815 	if (sport->lpuart32)
1816 		lpuart_reg.cons = LPUART32_CONSOLE;
1817 	else
1818 		lpuart_reg.cons = LPUART_CONSOLE;
1819 
1820 	ret = uart_add_one_port(&lpuart_reg, &sport->port);
1821 	if (ret) {
1822 		clk_disable_unprepare(sport->clk);
1823 		return ret;
1824 	}
1825 
1826 	sport->dma_tx_chan = dma_request_slave_channel(sport->port.dev, "tx");
1827 	if (!sport->dma_tx_chan)
1828 		dev_info(sport->port.dev, "DMA tx channel request failed, "
1829 				"operating without tx DMA\n");
1830 
1831 	sport->dma_rx_chan = dma_request_slave_channel(sport->port.dev, "rx");
1832 	if (!sport->dma_rx_chan)
1833 		dev_info(sport->port.dev, "DMA rx channel request failed, "
1834 				"operating without rx DMA\n");
1835 
1836 	return 0;
1837 }
1838 
1839 static int lpuart_remove(struct platform_device *pdev)
1840 {
1841 	struct lpuart_port *sport = platform_get_drvdata(pdev);
1842 
1843 	uart_remove_one_port(&lpuart_reg, &sport->port);
1844 
1845 	clk_disable_unprepare(sport->clk);
1846 
1847 	if (sport->dma_tx_chan)
1848 		dma_release_channel(sport->dma_tx_chan);
1849 
1850 	if (sport->dma_rx_chan)
1851 		dma_release_channel(sport->dma_rx_chan);
1852 
1853 	return 0;
1854 }
1855 
1856 #ifdef CONFIG_PM_SLEEP
1857 static int lpuart_suspend(struct device *dev)
1858 {
1859 	struct lpuart_port *sport = dev_get_drvdata(dev);
1860 	unsigned long temp;
1861 
1862 	if (sport->lpuart32) {
1863 		/* disable Rx/Tx and interrupts */
1864 		temp = lpuart32_read(sport->port.membase + UARTCTRL);
1865 		temp &= ~(UARTCTRL_TE | UARTCTRL_TIE | UARTCTRL_TCIE);
1866 		lpuart32_write(temp, sport->port.membase + UARTCTRL);
1867 	} else {
1868 		/* disable Rx/Tx and interrupts */
1869 		temp = readb(sport->port.membase + UARTCR2);
1870 		temp &= ~(UARTCR2_TE | UARTCR2_TIE | UARTCR2_TCIE);
1871 		writeb(temp, sport->port.membase + UARTCR2);
1872 	}
1873 
1874 	uart_suspend_port(&lpuart_reg, &sport->port);
1875 
1876 	return 0;
1877 }
1878 
1879 static int lpuart_resume(struct device *dev)
1880 {
1881 	struct lpuart_port *sport = dev_get_drvdata(dev);
1882 	unsigned long temp;
1883 
1884 	if (sport->lpuart32) {
1885 		lpuart32_setup_watermark(sport);
1886 		temp = lpuart32_read(sport->port.membase + UARTCTRL);
1887 		temp |= (UARTCTRL_RIE | UARTCTRL_TIE | UARTCTRL_RE |
1888 			 UARTCTRL_TE | UARTCTRL_ILIE);
1889 		lpuart32_write(temp, sport->port.membase + UARTCTRL);
1890 	} else {
1891 		lpuart_setup_watermark(sport);
1892 		temp = readb(sport->port.membase + UARTCR2);
1893 		temp |= (UARTCR2_RIE | UARTCR2_TIE | UARTCR2_RE | UARTCR2_TE);
1894 		writeb(temp, sport->port.membase + UARTCR2);
1895 	}
1896 
1897 	uart_resume_port(&lpuart_reg, &sport->port);
1898 
1899 	return 0;
1900 }
1901 #endif
1902 
1903 static SIMPLE_DEV_PM_OPS(lpuart_pm_ops, lpuart_suspend, lpuart_resume);
1904 
1905 static struct platform_driver lpuart_driver = {
1906 	.probe		= lpuart_probe,
1907 	.remove		= lpuart_remove,
1908 	.driver		= {
1909 		.name	= "fsl-lpuart",
1910 		.of_match_table = lpuart_dt_ids,
1911 		.pm	= &lpuart_pm_ops,
1912 	},
1913 };
1914 
1915 static int __init lpuart_serial_init(void)
1916 {
1917 	int ret = uart_register_driver(&lpuart_reg);
1918 
1919 	if (ret)
1920 		return ret;
1921 
1922 	ret = platform_driver_register(&lpuart_driver);
1923 	if (ret)
1924 		uart_unregister_driver(&lpuart_reg);
1925 
1926 	return ret;
1927 }
1928 
1929 static void __exit lpuart_serial_exit(void)
1930 {
1931 	platform_driver_unregister(&lpuart_driver);
1932 	uart_unregister_driver(&lpuart_reg);
1933 }
1934 
1935 module_init(lpuart_serial_init);
1936 module_exit(lpuart_serial_exit);
1937 
1938 MODULE_DESCRIPTION("Freescale lpuart serial port driver");
1939 MODULE_LICENSE("GPL v2");
1940