1/*
2 * Freescale STMP37XX/STMP378X Application UART driver
3 *
4 * Author: dmitry pervushin <dimka@embeddedalley.com>
5 *
6 * Copyright 2008-2010 Freescale Semiconductor, Inc.
7 * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
8 *
9 * The code contained herein is licensed under the GNU General Public
10 * License. You may obtain a copy of the GNU General Public License
11 * Version 2 or later at the following locations:
12 *
13 * http://www.opensource.org/licenses/gpl-license.html
14 * http://www.gnu.org/copyleft/gpl.html
15 */
16
17#if defined(CONFIG_SERIAL_MXS_AUART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
18#define SUPPORT_SYSRQ
19#endif
20
21#include <linux/kernel.h>
22#include <linux/errno.h>
23#include <linux/init.h>
24#include <linux/console.h>
25#include <linux/interrupt.h>
26#include <linux/module.h>
27#include <linux/slab.h>
28#include <linux/wait.h>
29#include <linux/tty.h>
30#include <linux/tty_driver.h>
31#include <linux/tty_flip.h>
32#include <linux/serial.h>
33#include <linux/serial_core.h>
34#include <linux/platform_device.h>
35#include <linux/device.h>
36#include <linux/clk.h>
37#include <linux/delay.h>
38#include <linux/io.h>
39#include <linux/of_device.h>
40#include <linux/dma-mapping.h>
41#include <linux/dmaengine.h>
42
43#include <asm/cacheflush.h>
44
45#include <linux/gpio.h>
46#include <linux/gpio/consumer.h>
47#include <linux/err.h>
48#include <linux/irq.h>
49#include "serial_mctrl_gpio.h"
50
51#define MXS_AUART_PORTS 5
52#define MXS_AUART_FIFO_SIZE		16
53
54#define AUART_CTRL0			0x00000000
55#define AUART_CTRL0_SET			0x00000004
56#define AUART_CTRL0_CLR			0x00000008
57#define AUART_CTRL0_TOG			0x0000000c
58#define AUART_CTRL1			0x00000010
59#define AUART_CTRL1_SET			0x00000014
60#define AUART_CTRL1_CLR			0x00000018
61#define AUART_CTRL1_TOG			0x0000001c
62#define AUART_CTRL2			0x00000020
63#define AUART_CTRL2_SET			0x00000024
64#define AUART_CTRL2_CLR			0x00000028
65#define AUART_CTRL2_TOG			0x0000002c
66#define AUART_LINECTRL			0x00000030
67#define AUART_LINECTRL_SET		0x00000034
68#define AUART_LINECTRL_CLR		0x00000038
69#define AUART_LINECTRL_TOG		0x0000003c
70#define AUART_LINECTRL2			0x00000040
71#define AUART_LINECTRL2_SET		0x00000044
72#define AUART_LINECTRL2_CLR		0x00000048
73#define AUART_LINECTRL2_TOG		0x0000004c
74#define AUART_INTR			0x00000050
75#define AUART_INTR_SET			0x00000054
76#define AUART_INTR_CLR			0x00000058
77#define AUART_INTR_TOG			0x0000005c
78#define AUART_DATA			0x00000060
79#define AUART_STAT			0x00000070
80#define AUART_DEBUG			0x00000080
81#define AUART_VERSION			0x00000090
82#define AUART_AUTOBAUD			0x000000a0
83
84#define AUART_CTRL0_SFTRST			(1 << 31)
85#define AUART_CTRL0_CLKGATE			(1 << 30)
86#define AUART_CTRL0_RXTO_ENABLE			(1 << 27)
87#define AUART_CTRL0_RXTIMEOUT(v)		(((v) & 0x7ff) << 16)
88#define AUART_CTRL0_XFER_COUNT(v)		((v) & 0xffff)
89
90#define AUART_CTRL1_XFER_COUNT(v)		((v) & 0xffff)
91
92#define AUART_CTRL2_DMAONERR			(1 << 26)
93#define AUART_CTRL2_TXDMAE			(1 << 25)
94#define AUART_CTRL2_RXDMAE			(1 << 24)
95
96#define AUART_CTRL2_CTSEN			(1 << 15)
97#define AUART_CTRL2_RTSEN			(1 << 14)
98#define AUART_CTRL2_RTS				(1 << 11)
99#define AUART_CTRL2_RXE				(1 << 9)
100#define AUART_CTRL2_TXE				(1 << 8)
101#define AUART_CTRL2_UARTEN			(1 << 0)
102
103#define AUART_LINECTRL_BAUD_DIVINT_SHIFT	16
104#define AUART_LINECTRL_BAUD_DIVINT_MASK		0xffff0000
105#define AUART_LINECTRL_BAUD_DIVINT(v)		(((v) & 0xffff) << 16)
106#define AUART_LINECTRL_BAUD_DIVFRAC_SHIFT	8
107#define AUART_LINECTRL_BAUD_DIVFRAC_MASK	0x00003f00
108#define AUART_LINECTRL_BAUD_DIVFRAC(v)		(((v) & 0x3f) << 8)
109#define AUART_LINECTRL_WLEN_MASK		0x00000060
110#define AUART_LINECTRL_WLEN(v)			(((v) & 0x3) << 5)
111#define AUART_LINECTRL_FEN			(1 << 4)
112#define AUART_LINECTRL_STP2			(1 << 3)
113#define AUART_LINECTRL_EPS			(1 << 2)
114#define AUART_LINECTRL_PEN			(1 << 1)
115#define AUART_LINECTRL_BRK			(1 << 0)
116
117#define AUART_INTR_RTIEN			(1 << 22)
118#define AUART_INTR_TXIEN			(1 << 21)
119#define AUART_INTR_RXIEN			(1 << 20)
120#define AUART_INTR_CTSMIEN			(1 << 17)
121#define AUART_INTR_RTIS				(1 << 6)
122#define AUART_INTR_TXIS				(1 << 5)
123#define AUART_INTR_RXIS				(1 << 4)
124#define AUART_INTR_CTSMIS			(1 << 1)
125
126#define AUART_STAT_BUSY				(1 << 29)
127#define AUART_STAT_CTS				(1 << 28)
128#define AUART_STAT_TXFE				(1 << 27)
129#define AUART_STAT_TXFF				(1 << 25)
130#define AUART_STAT_RXFE				(1 << 24)
131#define AUART_STAT_OERR				(1 << 19)
132#define AUART_STAT_BERR				(1 << 18)
133#define AUART_STAT_PERR				(1 << 17)
134#define AUART_STAT_FERR				(1 << 16)
135#define AUART_STAT_RXCOUNT_MASK			0xffff
136
137static struct uart_driver auart_driver;
138
139enum mxs_auart_type {
140	IMX23_AUART,
141	IMX28_AUART,
142};
143
144struct mxs_auart_port {
145	struct uart_port port;
146
147#define MXS_AUART_DMA_ENABLED	0x2
148#define MXS_AUART_DMA_TX_SYNC	2  /* bit 2 */
149#define MXS_AUART_DMA_RX_READY	3  /* bit 3 */
150#define MXS_AUART_RTSCTS	4  /* bit 4 */
151	unsigned long flags;
152	unsigned int mctrl_prev;
153	enum mxs_auart_type devtype;
154
155	struct clk *clk;
156	struct device *dev;
157
158	/* for DMA */
159	struct scatterlist tx_sgl;
160	struct dma_chan	*tx_dma_chan;
161	void *tx_dma_buf;
162
163	struct scatterlist rx_sgl;
164	struct dma_chan	*rx_dma_chan;
165	void *rx_dma_buf;
166
167	struct mctrl_gpios	*gpios;
168	int			gpio_irq[UART_GPIO_MAX];
169	bool			ms_irq_enabled;
170};
171
172static struct platform_device_id mxs_auart_devtype[] = {
173	{ .name = "mxs-auart-imx23", .driver_data = IMX23_AUART },
174	{ .name = "mxs-auart-imx28", .driver_data = IMX28_AUART },
175	{ /* sentinel */ }
176};
177MODULE_DEVICE_TABLE(platform, mxs_auart_devtype);
178
179static const struct of_device_id mxs_auart_dt_ids[] = {
180	{
181		.compatible = "fsl,imx28-auart",
182		.data = &mxs_auart_devtype[IMX28_AUART]
183	}, {
184		.compatible = "fsl,imx23-auart",
185		.data = &mxs_auart_devtype[IMX23_AUART]
186	}, { /* sentinel */ }
187};
188MODULE_DEVICE_TABLE(of, mxs_auart_dt_ids);
189
190static inline int is_imx28_auart(struct mxs_auart_port *s)
191{
192	return s->devtype == IMX28_AUART;
193}
194
195static inline bool auart_dma_enabled(struct mxs_auart_port *s)
196{
197	return s->flags & MXS_AUART_DMA_ENABLED;
198}
199
200static void mxs_auart_stop_tx(struct uart_port *u);
201
202#define to_auart_port(u) container_of(u, struct mxs_auart_port, port)
203
204static void mxs_auart_tx_chars(struct mxs_auart_port *s);
205
206static void dma_tx_callback(void *param)
207{
208	struct mxs_auart_port *s = param;
209	struct circ_buf *xmit = &s->port.state->xmit;
210
211	dma_unmap_sg(s->dev, &s->tx_sgl, 1, DMA_TO_DEVICE);
212
213	/* clear the bit used to serialize the DMA tx. */
214	clear_bit(MXS_AUART_DMA_TX_SYNC, &s->flags);
215	smp_mb__after_atomic();
216
217	/* wake up the possible processes. */
218	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
219		uart_write_wakeup(&s->port);
220
221	mxs_auart_tx_chars(s);
222}
223
224static int mxs_auart_dma_tx(struct mxs_auart_port *s, int size)
225{
226	struct dma_async_tx_descriptor *desc;
227	struct scatterlist *sgl = &s->tx_sgl;
228	struct dma_chan *channel = s->tx_dma_chan;
229	u32 pio;
230
231	/* [1] : send PIO. Note, the first pio word is CTRL1. */
232	pio = AUART_CTRL1_XFER_COUNT(size);
233	desc = dmaengine_prep_slave_sg(channel, (struct scatterlist *)&pio,
234					1, DMA_TRANS_NONE, 0);
235	if (!desc) {
236		dev_err(s->dev, "step 1 error\n");
237		return -EINVAL;
238	}
239
240	/* [2] : set DMA buffer. */
241	sg_init_one(sgl, s->tx_dma_buf, size);
242	dma_map_sg(s->dev, sgl, 1, DMA_TO_DEVICE);
243	desc = dmaengine_prep_slave_sg(channel, sgl,
244			1, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
245	if (!desc) {
246		dev_err(s->dev, "step 2 error\n");
247		return -EINVAL;
248	}
249
250	/* [3] : submit the DMA */
251	desc->callback = dma_tx_callback;
252	desc->callback_param = s;
253	dmaengine_submit(desc);
254	dma_async_issue_pending(channel);
255	return 0;
256}
257
258static void mxs_auart_tx_chars(struct mxs_auart_port *s)
259{
260	struct circ_buf *xmit = &s->port.state->xmit;
261
262	if (auart_dma_enabled(s)) {
263		u32 i = 0;
264		int size;
265		void *buffer = s->tx_dma_buf;
266
267		if (test_and_set_bit(MXS_AUART_DMA_TX_SYNC, &s->flags))
268			return;
269
270		while (!uart_circ_empty(xmit) && !uart_tx_stopped(&s->port)) {
271			size = min_t(u32, UART_XMIT_SIZE - i,
272				     CIRC_CNT_TO_END(xmit->head,
273						     xmit->tail,
274						     UART_XMIT_SIZE));
275			memcpy(buffer + i, xmit->buf + xmit->tail, size);
276			xmit->tail = (xmit->tail + size) & (UART_XMIT_SIZE - 1);
277
278			i += size;
279			if (i >= UART_XMIT_SIZE)
280				break;
281		}
282
283		if (uart_tx_stopped(&s->port))
284			mxs_auart_stop_tx(&s->port);
285
286		if (i) {
287			mxs_auart_dma_tx(s, i);
288		} else {
289			clear_bit(MXS_AUART_DMA_TX_SYNC, &s->flags);
290			smp_mb__after_atomic();
291		}
292		return;
293	}
294
295
296	while (!(readl(s->port.membase + AUART_STAT) &
297		 AUART_STAT_TXFF)) {
298		if (s->port.x_char) {
299			s->port.icount.tx++;
300			writel(s->port.x_char,
301				     s->port.membase + AUART_DATA);
302			s->port.x_char = 0;
303			continue;
304		}
305		if (!uart_circ_empty(xmit) && !uart_tx_stopped(&s->port)) {
306			s->port.icount.tx++;
307			writel(xmit->buf[xmit->tail],
308				     s->port.membase + AUART_DATA);
309			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
310		} else
311			break;
312	}
313	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
314		uart_write_wakeup(&s->port);
315
316	if (uart_circ_empty(&(s->port.state->xmit)))
317		writel(AUART_INTR_TXIEN,
318			     s->port.membase + AUART_INTR_CLR);
319	else
320		writel(AUART_INTR_TXIEN,
321			     s->port.membase + AUART_INTR_SET);
322
323	if (uart_tx_stopped(&s->port))
324		mxs_auart_stop_tx(&s->port);
325}
326
327static void mxs_auart_rx_char(struct mxs_auart_port *s)
328{
329	int flag;
330	u32 stat;
331	u8 c;
332
333	c = readl(s->port.membase + AUART_DATA);
334	stat = readl(s->port.membase + AUART_STAT);
335
336	flag = TTY_NORMAL;
337	s->port.icount.rx++;
338
339	if (stat & AUART_STAT_BERR) {
340		s->port.icount.brk++;
341		if (uart_handle_break(&s->port))
342			goto out;
343	} else if (stat & AUART_STAT_PERR) {
344		s->port.icount.parity++;
345	} else if (stat & AUART_STAT_FERR) {
346		s->port.icount.frame++;
347	}
348
349	/*
350	 * Mask off conditions which should be ingored.
351	 */
352	stat &= s->port.read_status_mask;
353
354	if (stat & AUART_STAT_BERR) {
355		flag = TTY_BREAK;
356	} else if (stat & AUART_STAT_PERR)
357		flag = TTY_PARITY;
358	else if (stat & AUART_STAT_FERR)
359		flag = TTY_FRAME;
360
361	if (stat & AUART_STAT_OERR)
362		s->port.icount.overrun++;
363
364	if (uart_handle_sysrq_char(&s->port, c))
365		goto out;
366
367	uart_insert_char(&s->port, stat, AUART_STAT_OERR, c, flag);
368out:
369	writel(stat, s->port.membase + AUART_STAT);
370}
371
372static void mxs_auart_rx_chars(struct mxs_auart_port *s)
373{
374	u32 stat = 0;
375
376	for (;;) {
377		stat = readl(s->port.membase + AUART_STAT);
378		if (stat & AUART_STAT_RXFE)
379			break;
380		mxs_auart_rx_char(s);
381	}
382
383	writel(stat, s->port.membase + AUART_STAT);
384	tty_flip_buffer_push(&s->port.state->port);
385}
386
387static int mxs_auart_request_port(struct uart_port *u)
388{
389	return 0;
390}
391
392static int mxs_auart_verify_port(struct uart_port *u,
393				    struct serial_struct *ser)
394{
395	if (u->type != PORT_UNKNOWN && u->type != PORT_IMX)
396		return -EINVAL;
397	return 0;
398}
399
400static void mxs_auart_config_port(struct uart_port *u, int flags)
401{
402}
403
404static const char *mxs_auart_type(struct uart_port *u)
405{
406	struct mxs_auart_port *s = to_auart_port(u);
407
408	return dev_name(s->dev);
409}
410
411static void mxs_auart_release_port(struct uart_port *u)
412{
413}
414
415static void mxs_auart_set_mctrl(struct uart_port *u, unsigned mctrl)
416{
417	struct mxs_auart_port *s = to_auart_port(u);
418
419	u32 ctrl = readl(u->membase + AUART_CTRL2);
420
421	ctrl &= ~(AUART_CTRL2_RTSEN | AUART_CTRL2_RTS);
422	if (mctrl & TIOCM_RTS) {
423		if (uart_cts_enabled(u))
424			ctrl |= AUART_CTRL2_RTSEN;
425		else
426			ctrl |= AUART_CTRL2_RTS;
427	}
428
429	writel(ctrl, u->membase + AUART_CTRL2);
430
431	mctrl_gpio_set(s->gpios, mctrl);
432}
433
434#define MCTRL_ANY_DELTA        (TIOCM_RI | TIOCM_DSR | TIOCM_CD | TIOCM_CTS)
435static u32 mxs_auart_modem_status(struct mxs_auart_port *s, u32 mctrl)
436{
437	u32 mctrl_diff;
438
439	mctrl_diff = mctrl ^ s->mctrl_prev;
440	s->mctrl_prev = mctrl;
441	if (mctrl_diff & MCTRL_ANY_DELTA && s->ms_irq_enabled &&
442						s->port.state != NULL) {
443		if (mctrl_diff & TIOCM_RI)
444			s->port.icount.rng++;
445		if (mctrl_diff & TIOCM_DSR)
446			s->port.icount.dsr++;
447		if (mctrl_diff & TIOCM_CD)
448			uart_handle_dcd_change(&s->port, mctrl & TIOCM_CD);
449		if (mctrl_diff & TIOCM_CTS)
450			uart_handle_cts_change(&s->port, mctrl & TIOCM_CTS);
451
452		wake_up_interruptible(&s->port.state->port.delta_msr_wait);
453	}
454	return mctrl;
455}
456
457static u32 mxs_auart_get_mctrl(struct uart_port *u)
458{
459	struct mxs_auart_port *s = to_auart_port(u);
460	u32 stat = readl(u->membase + AUART_STAT);
461	u32 mctrl = 0;
462
463	if (stat & AUART_STAT_CTS)
464		mctrl |= TIOCM_CTS;
465
466	return mctrl_gpio_get(s->gpios, &mctrl);
467}
468
469/*
470 * Enable modem status interrupts
471 */
472static void mxs_auart_enable_ms(struct uart_port *port)
473{
474	struct mxs_auart_port *s = to_auart_port(port);
475
476	/*
477	 * Interrupt should not be enabled twice
478	 */
479	if (s->ms_irq_enabled)
480		return;
481
482	s->ms_irq_enabled = true;
483
484	if (s->gpio_irq[UART_GPIO_CTS] >= 0)
485		enable_irq(s->gpio_irq[UART_GPIO_CTS]);
486	/* TODO: enable AUART_INTR_CTSMIEN otherwise */
487
488	if (s->gpio_irq[UART_GPIO_DSR] >= 0)
489		enable_irq(s->gpio_irq[UART_GPIO_DSR]);
490
491	if (s->gpio_irq[UART_GPIO_RI] >= 0)
492		enable_irq(s->gpio_irq[UART_GPIO_RI]);
493
494	if (s->gpio_irq[UART_GPIO_DCD] >= 0)
495		enable_irq(s->gpio_irq[UART_GPIO_DCD]);
496}
497
498/*
499 * Disable modem status interrupts
500 */
501static void mxs_auart_disable_ms(struct uart_port *port)
502{
503	struct mxs_auart_port *s = to_auart_port(port);
504
505	/*
506	 * Interrupt should not be disabled twice
507	 */
508	if (!s->ms_irq_enabled)
509		return;
510
511	s->ms_irq_enabled = false;
512
513	if (s->gpio_irq[UART_GPIO_CTS] >= 0)
514		disable_irq(s->gpio_irq[UART_GPIO_CTS]);
515	/* TODO: disable AUART_INTR_CTSMIEN otherwise */
516
517	if (s->gpio_irq[UART_GPIO_DSR] >= 0)
518		disable_irq(s->gpio_irq[UART_GPIO_DSR]);
519
520	if (s->gpio_irq[UART_GPIO_RI] >= 0)
521		disable_irq(s->gpio_irq[UART_GPIO_RI]);
522
523	if (s->gpio_irq[UART_GPIO_DCD] >= 0)
524		disable_irq(s->gpio_irq[UART_GPIO_DCD]);
525}
526
527static int mxs_auart_dma_prep_rx(struct mxs_auart_port *s);
528static void dma_rx_callback(void *arg)
529{
530	struct mxs_auart_port *s = (struct mxs_auart_port *) arg;
531	struct tty_port *port = &s->port.state->port;
532	int count;
533	u32 stat;
534
535	dma_unmap_sg(s->dev, &s->rx_sgl, 1, DMA_FROM_DEVICE);
536
537	stat = readl(s->port.membase + AUART_STAT);
538	stat &= ~(AUART_STAT_OERR | AUART_STAT_BERR |
539			AUART_STAT_PERR | AUART_STAT_FERR);
540
541	count = stat & AUART_STAT_RXCOUNT_MASK;
542	tty_insert_flip_string(port, s->rx_dma_buf, count);
543
544	writel(stat, s->port.membase + AUART_STAT);
545	tty_flip_buffer_push(port);
546
547	/* start the next DMA for RX. */
548	mxs_auart_dma_prep_rx(s);
549}
550
551static int mxs_auart_dma_prep_rx(struct mxs_auart_port *s)
552{
553	struct dma_async_tx_descriptor *desc;
554	struct scatterlist *sgl = &s->rx_sgl;
555	struct dma_chan *channel = s->rx_dma_chan;
556	u32 pio[1];
557
558	/* [1] : send PIO */
559	pio[0] = AUART_CTRL0_RXTO_ENABLE
560		| AUART_CTRL0_RXTIMEOUT(0x80)
561		| AUART_CTRL0_XFER_COUNT(UART_XMIT_SIZE);
562	desc = dmaengine_prep_slave_sg(channel, (struct scatterlist *)pio,
563					1, DMA_TRANS_NONE, 0);
564	if (!desc) {
565		dev_err(s->dev, "step 1 error\n");
566		return -EINVAL;
567	}
568
569	/* [2] : send DMA request */
570	sg_init_one(sgl, s->rx_dma_buf, UART_XMIT_SIZE);
571	dma_map_sg(s->dev, sgl, 1, DMA_FROM_DEVICE);
572	desc = dmaengine_prep_slave_sg(channel, sgl, 1, DMA_DEV_TO_MEM,
573					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
574	if (!desc) {
575		dev_err(s->dev, "step 2 error\n");
576		return -1;
577	}
578
579	/* [3] : submit the DMA, but do not issue it. */
580	desc->callback = dma_rx_callback;
581	desc->callback_param = s;
582	dmaengine_submit(desc);
583	dma_async_issue_pending(channel);
584	return 0;
585}
586
587static void mxs_auart_dma_exit_channel(struct mxs_auart_port *s)
588{
589	if (s->tx_dma_chan) {
590		dma_release_channel(s->tx_dma_chan);
591		s->tx_dma_chan = NULL;
592	}
593	if (s->rx_dma_chan) {
594		dma_release_channel(s->rx_dma_chan);
595		s->rx_dma_chan = NULL;
596	}
597
598	kfree(s->tx_dma_buf);
599	kfree(s->rx_dma_buf);
600	s->tx_dma_buf = NULL;
601	s->rx_dma_buf = NULL;
602}
603
604static void mxs_auart_dma_exit(struct mxs_auart_port *s)
605{
606
607	writel(AUART_CTRL2_TXDMAE | AUART_CTRL2_RXDMAE | AUART_CTRL2_DMAONERR,
608		s->port.membase + AUART_CTRL2_CLR);
609
610	mxs_auart_dma_exit_channel(s);
611	s->flags &= ~MXS_AUART_DMA_ENABLED;
612	clear_bit(MXS_AUART_DMA_TX_SYNC, &s->flags);
613	clear_bit(MXS_AUART_DMA_RX_READY, &s->flags);
614}
615
616static int mxs_auart_dma_init(struct mxs_auart_port *s)
617{
618	if (auart_dma_enabled(s))
619		return 0;
620
621	/* init for RX */
622	s->rx_dma_chan = dma_request_slave_channel(s->dev, "rx");
623	if (!s->rx_dma_chan)
624		goto err_out;
625	s->rx_dma_buf = kzalloc(UART_XMIT_SIZE, GFP_KERNEL | GFP_DMA);
626	if (!s->rx_dma_buf)
627		goto err_out;
628
629	/* init for TX */
630	s->tx_dma_chan = dma_request_slave_channel(s->dev, "tx");
631	if (!s->tx_dma_chan)
632		goto err_out;
633	s->tx_dma_buf = kzalloc(UART_XMIT_SIZE, GFP_KERNEL | GFP_DMA);
634	if (!s->tx_dma_buf)
635		goto err_out;
636
637	/* set the flags */
638	s->flags |= MXS_AUART_DMA_ENABLED;
639	dev_dbg(s->dev, "enabled the DMA support.");
640
641	/* The DMA buffer is now the FIFO the TTY subsystem can use */
642	s->port.fifosize = UART_XMIT_SIZE;
643
644	return 0;
645
646err_out:
647	mxs_auart_dma_exit_channel(s);
648	return -EINVAL;
649
650}
651
652#define RTS_AT_AUART()	IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(s->gpios,	\
653							UART_GPIO_RTS))
654#define CTS_AT_AUART()	IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(s->gpios,	\
655							UART_GPIO_CTS))
656static void mxs_auart_settermios(struct uart_port *u,
657				 struct ktermios *termios,
658				 struct ktermios *old)
659{
660	struct mxs_auart_port *s = to_auart_port(u);
661	u32 bm, ctrl, ctrl2, div;
662	unsigned int cflag, baud;
663
664	cflag = termios->c_cflag;
665
666	ctrl = AUART_LINECTRL_FEN;
667	ctrl2 = readl(u->membase + AUART_CTRL2);
668
669	/* byte size */
670	switch (cflag & CSIZE) {
671	case CS5:
672		bm = 0;
673		break;
674	case CS6:
675		bm = 1;
676		break;
677	case CS7:
678		bm = 2;
679		break;
680	case CS8:
681		bm = 3;
682		break;
683	default:
684		return;
685	}
686
687	ctrl |= AUART_LINECTRL_WLEN(bm);
688
689	/* parity */
690	if (cflag & PARENB) {
691		ctrl |= AUART_LINECTRL_PEN;
692		if ((cflag & PARODD) == 0)
693			ctrl |= AUART_LINECTRL_EPS;
694	}
695
696	u->read_status_mask = 0;
697
698	if (termios->c_iflag & INPCK)
699		u->read_status_mask |= AUART_STAT_PERR;
700	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
701		u->read_status_mask |= AUART_STAT_BERR;
702
703	/*
704	 * Characters to ignore
705	 */
706	u->ignore_status_mask = 0;
707	if (termios->c_iflag & IGNPAR)
708		u->ignore_status_mask |= AUART_STAT_PERR;
709	if (termios->c_iflag & IGNBRK) {
710		u->ignore_status_mask |= AUART_STAT_BERR;
711		/*
712		 * If we're ignoring parity and break indicators,
713		 * ignore overruns too (for real raw support).
714		 */
715		if (termios->c_iflag & IGNPAR)
716			u->ignore_status_mask |= AUART_STAT_OERR;
717	}
718
719	/*
720	 * ignore all characters if CREAD is not set
721	 */
722	if (cflag & CREAD)
723		ctrl2 |= AUART_CTRL2_RXE;
724	else
725		ctrl2 &= ~AUART_CTRL2_RXE;
726
727	/* figure out the stop bits requested */
728	if (cflag & CSTOPB)
729		ctrl |= AUART_LINECTRL_STP2;
730
731	/* figure out the hardware flow control settings */
732	ctrl2 &= ~(AUART_CTRL2_CTSEN | AUART_CTRL2_RTSEN);
733	if (cflag & CRTSCTS) {
734		/*
735		 * The DMA has a bug(see errata:2836) in mx23.
736		 * So we can not implement the DMA for auart in mx23,
737		 * we can only implement the DMA support for auart
738		 * in mx28.
739		 */
740		if (is_imx28_auart(s)
741				&& test_bit(MXS_AUART_RTSCTS, &s->flags)) {
742			if (!mxs_auart_dma_init(s))
743				/* enable DMA tranfer */
744				ctrl2 |= AUART_CTRL2_TXDMAE | AUART_CTRL2_RXDMAE
745				       | AUART_CTRL2_DMAONERR;
746		}
747		/* Even if RTS is GPIO line RTSEN can be enabled because
748		 * the pinctrl configuration decides about RTS pin function */
749		ctrl2 |= AUART_CTRL2_RTSEN;
750		if (CTS_AT_AUART())
751			ctrl2 |= AUART_CTRL2_CTSEN;
752	}
753
754	/* set baud rate */
755	baud = uart_get_baud_rate(u, termios, old, 0, u->uartclk);
756	div = u->uartclk * 32 / baud;
757	ctrl |= AUART_LINECTRL_BAUD_DIVFRAC(div & 0x3F);
758	ctrl |= AUART_LINECTRL_BAUD_DIVINT(div >> 6);
759
760	writel(ctrl, u->membase + AUART_LINECTRL);
761	writel(ctrl2, u->membase + AUART_CTRL2);
762
763	uart_update_timeout(u, termios->c_cflag, baud);
764
765	/* prepare for the DMA RX. */
766	if (auart_dma_enabled(s) &&
767		!test_and_set_bit(MXS_AUART_DMA_RX_READY, &s->flags)) {
768		if (!mxs_auart_dma_prep_rx(s)) {
769			/* Disable the normal RX interrupt. */
770			writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN,
771					u->membase + AUART_INTR_CLR);
772		} else {
773			mxs_auart_dma_exit(s);
774			dev_err(s->dev, "We can not start up the DMA.\n");
775		}
776	}
777
778	/* CTS flow-control and modem-status interrupts */
779	if (UART_ENABLE_MS(u, termios->c_cflag))
780		mxs_auart_enable_ms(u);
781	else
782		mxs_auart_disable_ms(u);
783}
784
785static void mxs_auart_set_ldisc(struct uart_port *port,
786				struct ktermios *termios)
787{
788	if (termios->c_line == N_PPS) {
789		port->flags |= UPF_HARDPPS_CD;
790		mxs_auart_enable_ms(port);
791	} else {
792		port->flags &= ~UPF_HARDPPS_CD;
793	}
794}
795
796static irqreturn_t mxs_auart_irq_handle(int irq, void *context)
797{
798	u32 istat;
799	struct mxs_auart_port *s = context;
800	u32 mctrl_temp = s->mctrl_prev;
801	u32 stat = readl(s->port.membase + AUART_STAT);
802
803	istat = readl(s->port.membase + AUART_INTR);
804
805	/* ack irq */
806	writel(istat & (AUART_INTR_RTIS
807		| AUART_INTR_TXIS
808		| AUART_INTR_RXIS
809		| AUART_INTR_CTSMIS),
810			s->port.membase + AUART_INTR_CLR);
811
812	/*
813	 * Dealing with GPIO interrupt
814	 */
815	if (irq == s->gpio_irq[UART_GPIO_CTS] ||
816	    irq == s->gpio_irq[UART_GPIO_DCD] ||
817	    irq == s->gpio_irq[UART_GPIO_DSR] ||
818	    irq == s->gpio_irq[UART_GPIO_RI])
819		mxs_auart_modem_status(s,
820				mctrl_gpio_get(s->gpios, &mctrl_temp));
821
822	if (istat & AUART_INTR_CTSMIS) {
823		if (CTS_AT_AUART() && s->ms_irq_enabled)
824			uart_handle_cts_change(&s->port,
825					stat & AUART_STAT_CTS);
826		writel(AUART_INTR_CTSMIS,
827				s->port.membase + AUART_INTR_CLR);
828		istat &= ~AUART_INTR_CTSMIS;
829	}
830
831	if (istat & (AUART_INTR_RTIS | AUART_INTR_RXIS)) {
832		if (!auart_dma_enabled(s))
833			mxs_auart_rx_chars(s);
834		istat &= ~(AUART_INTR_RTIS | AUART_INTR_RXIS);
835	}
836
837	if (istat & AUART_INTR_TXIS) {
838		mxs_auart_tx_chars(s);
839		istat &= ~AUART_INTR_TXIS;
840	}
841
842	return IRQ_HANDLED;
843}
844
845static void mxs_auart_reset(struct uart_port *u)
846{
847	int i;
848	unsigned int reg;
849
850	writel(AUART_CTRL0_SFTRST, u->membase + AUART_CTRL0_CLR);
851
852	for (i = 0; i < 10000; i++) {
853		reg = readl(u->membase + AUART_CTRL0);
854		if (!(reg & AUART_CTRL0_SFTRST))
855			break;
856		udelay(3);
857	}
858	writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR);
859}
860
861static int mxs_auart_startup(struct uart_port *u)
862{
863	int ret;
864	struct mxs_auart_port *s = to_auart_port(u);
865
866	ret = clk_prepare_enable(s->clk);
867	if (ret)
868		return ret;
869
870	writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR);
871
872	writel(AUART_CTRL2_UARTEN, u->membase + AUART_CTRL2_SET);
873
874	writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN,
875			u->membase + AUART_INTR);
876
877	/* Reset FIFO size (it could have changed if DMA was enabled) */
878	u->fifosize = MXS_AUART_FIFO_SIZE;
879
880	/*
881	 * Enable fifo so all four bytes of a DMA word are written to
882	 * output (otherwise, only the LSB is written, ie. 1 in 4 bytes)
883	 */
884	writel(AUART_LINECTRL_FEN, u->membase + AUART_LINECTRL_SET);
885
886	/* get initial status of modem lines */
887	mctrl_gpio_get(s->gpios, &s->mctrl_prev);
888
889	s->ms_irq_enabled = false;
890	return 0;
891}
892
893static void mxs_auart_shutdown(struct uart_port *u)
894{
895	struct mxs_auart_port *s = to_auart_port(u);
896
897	mxs_auart_disable_ms(u);
898
899	if (auart_dma_enabled(s))
900		mxs_auart_dma_exit(s);
901
902	writel(AUART_CTRL2_UARTEN, u->membase + AUART_CTRL2_CLR);
903
904	writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN,
905			u->membase + AUART_INTR_CLR);
906
907	writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_SET);
908
909	clk_disable_unprepare(s->clk);
910}
911
912static unsigned int mxs_auart_tx_empty(struct uart_port *u)
913{
914	if ((readl(u->membase + AUART_STAT) &
915		 (AUART_STAT_TXFE | AUART_STAT_BUSY)) == AUART_STAT_TXFE)
916		return TIOCSER_TEMT;
917
918	return 0;
919}
920
921static void mxs_auart_start_tx(struct uart_port *u)
922{
923	struct mxs_auart_port *s = to_auart_port(u);
924
925	/* enable transmitter */
926	writel(AUART_CTRL2_TXE, u->membase + AUART_CTRL2_SET);
927
928	mxs_auart_tx_chars(s);
929}
930
931static void mxs_auart_stop_tx(struct uart_port *u)
932{
933	writel(AUART_CTRL2_TXE, u->membase + AUART_CTRL2_CLR);
934}
935
936static void mxs_auart_stop_rx(struct uart_port *u)
937{
938	writel(AUART_CTRL2_RXE, u->membase + AUART_CTRL2_CLR);
939}
940
941static void mxs_auart_break_ctl(struct uart_port *u, int ctl)
942{
943	if (ctl)
944		writel(AUART_LINECTRL_BRK,
945			     u->membase + AUART_LINECTRL_SET);
946	else
947		writel(AUART_LINECTRL_BRK,
948			     u->membase + AUART_LINECTRL_CLR);
949}
950
951static struct uart_ops mxs_auart_ops = {
952	.tx_empty       = mxs_auart_tx_empty,
953	.start_tx       = mxs_auart_start_tx,
954	.stop_tx	= mxs_auart_stop_tx,
955	.stop_rx	= mxs_auart_stop_rx,
956	.enable_ms      = mxs_auart_enable_ms,
957	.break_ctl      = mxs_auart_break_ctl,
958	.set_mctrl	= mxs_auart_set_mctrl,
959	.get_mctrl      = mxs_auart_get_mctrl,
960	.startup	= mxs_auart_startup,
961	.shutdown       = mxs_auart_shutdown,
962	.set_termios    = mxs_auart_settermios,
963	.set_ldisc      = mxs_auart_set_ldisc,
964	.type	   	= mxs_auart_type,
965	.release_port   = mxs_auart_release_port,
966	.request_port   = mxs_auart_request_port,
967	.config_port    = mxs_auart_config_port,
968	.verify_port    = mxs_auart_verify_port,
969};
970
971static struct mxs_auart_port *auart_port[MXS_AUART_PORTS];
972
973#ifdef CONFIG_SERIAL_MXS_AUART_CONSOLE
974static void mxs_auart_console_putchar(struct uart_port *port, int ch)
975{
976	unsigned int to = 1000;
977
978	while (readl(port->membase + AUART_STAT) & AUART_STAT_TXFF) {
979		if (!to--)
980			break;
981		udelay(1);
982	}
983
984	writel(ch, port->membase + AUART_DATA);
985}
986
987static void
988auart_console_write(struct console *co, const char *str, unsigned int count)
989{
990	struct mxs_auart_port *s;
991	struct uart_port *port;
992	unsigned int old_ctrl0, old_ctrl2;
993	unsigned int to = 20000;
994
995	if (co->index >= MXS_AUART_PORTS || co->index < 0)
996		return;
997
998	s = auart_port[co->index];
999	port = &s->port;
1000
1001	clk_enable(s->clk);
1002
1003	/* First save the CR then disable the interrupts */
1004	old_ctrl2 = readl(port->membase + AUART_CTRL2);
1005	old_ctrl0 = readl(port->membase + AUART_CTRL0);
1006
1007	writel(AUART_CTRL0_CLKGATE,
1008		     port->membase + AUART_CTRL0_CLR);
1009	writel(AUART_CTRL2_UARTEN | AUART_CTRL2_TXE,
1010		     port->membase + AUART_CTRL2_SET);
1011
1012	uart_console_write(port, str, count, mxs_auart_console_putchar);
1013
1014	/* Finally, wait for transmitter to become empty ... */
1015	while (readl(port->membase + AUART_STAT) & AUART_STAT_BUSY) {
1016		udelay(1);
1017		if (!to--)
1018			break;
1019	}
1020
1021	/*
1022	 * ... and restore the TCR if we waited long enough for the transmitter
1023	 * to be idle. This might keep the transmitter enabled although it is
1024	 * unused, but that is better than to disable it while it is still
1025	 * transmitting.
1026	 */
1027	if (!(readl(port->membase + AUART_STAT) & AUART_STAT_BUSY)) {
1028		writel(old_ctrl0, port->membase + AUART_CTRL0);
1029		writel(old_ctrl2, port->membase + AUART_CTRL2);
1030	}
1031
1032	clk_disable(s->clk);
1033}
1034
1035static void __init
1036auart_console_get_options(struct uart_port *port, int *baud,
1037			  int *parity, int *bits)
1038{
1039	unsigned int lcr_h, quot;
1040
1041	if (!(readl(port->membase + AUART_CTRL2) & AUART_CTRL2_UARTEN))
1042		return;
1043
1044	lcr_h = readl(port->membase + AUART_LINECTRL);
1045
1046	*parity = 'n';
1047	if (lcr_h & AUART_LINECTRL_PEN) {
1048		if (lcr_h & AUART_LINECTRL_EPS)
1049			*parity = 'e';
1050		else
1051			*parity = 'o';
1052	}
1053
1054	if ((lcr_h & AUART_LINECTRL_WLEN_MASK) == AUART_LINECTRL_WLEN(2))
1055		*bits = 7;
1056	else
1057		*bits = 8;
1058
1059	quot = ((readl(port->membase + AUART_LINECTRL)
1060			& AUART_LINECTRL_BAUD_DIVINT_MASK))
1061			    >> (AUART_LINECTRL_BAUD_DIVINT_SHIFT - 6);
1062	quot |= ((readl(port->membase + AUART_LINECTRL)
1063			& AUART_LINECTRL_BAUD_DIVFRAC_MASK))
1064				>> AUART_LINECTRL_BAUD_DIVFRAC_SHIFT;
1065	if (quot == 0)
1066		quot = 1;
1067
1068	*baud = (port->uartclk << 2) / quot;
1069}
1070
1071static int __init
1072auart_console_setup(struct console *co, char *options)
1073{
1074	struct mxs_auart_port *s;
1075	int baud = 9600;
1076	int bits = 8;
1077	int parity = 'n';
1078	int flow = 'n';
1079	int ret;
1080
1081	/*
1082	 * Check whether an invalid uart number has been specified, and
1083	 * if so, search for the first available port that does have
1084	 * console support.
1085	 */
1086	if (co->index == -1 || co->index >= ARRAY_SIZE(auart_port))
1087		co->index = 0;
1088	s = auart_port[co->index];
1089	if (!s)
1090		return -ENODEV;
1091
1092	ret = clk_prepare_enable(s->clk);
1093	if (ret)
1094		return ret;
1095
1096	if (options)
1097		uart_parse_options(options, &baud, &parity, &bits, &flow);
1098	else
1099		auart_console_get_options(&s->port, &baud, &parity, &bits);
1100
1101	ret = uart_set_options(&s->port, co, baud, parity, bits, flow);
1102
1103	clk_disable_unprepare(s->clk);
1104
1105	return ret;
1106}
1107
1108static struct console auart_console = {
1109	.name		= "ttyAPP",
1110	.write		= auart_console_write,
1111	.device		= uart_console_device,
1112	.setup		= auart_console_setup,
1113	.flags		= CON_PRINTBUFFER,
1114	.index		= -1,
1115	.data		= &auart_driver,
1116};
1117#endif
1118
1119static struct uart_driver auart_driver = {
1120	.owner		= THIS_MODULE,
1121	.driver_name	= "ttyAPP",
1122	.dev_name	= "ttyAPP",
1123	.major		= 0,
1124	.minor		= 0,
1125	.nr		= MXS_AUART_PORTS,
1126#ifdef CONFIG_SERIAL_MXS_AUART_CONSOLE
1127	.cons =		&auart_console,
1128#endif
1129};
1130
1131/*
1132 * This function returns 1 if pdev isn't a device instatiated by dt, 0 if it
1133 * could successfully get all information from dt or a negative errno.
1134 */
1135static int serial_mxs_probe_dt(struct mxs_auart_port *s,
1136		struct platform_device *pdev)
1137{
1138	struct device_node *np = pdev->dev.of_node;
1139	int ret;
1140
1141	if (!np)
1142		/* no device tree device */
1143		return 1;
1144
1145	ret = of_alias_get_id(np, "serial");
1146	if (ret < 0) {
1147		dev_err(&pdev->dev, "failed to get alias id: %d\n", ret);
1148		return ret;
1149	}
1150	s->port.line = ret;
1151
1152	if (of_get_property(np, "fsl,uart-has-rtscts", NULL))
1153		set_bit(MXS_AUART_RTSCTS, &s->flags);
1154
1155	return 0;
1156}
1157
1158static int mxs_auart_init_gpios(struct mxs_auart_port *s, struct device *dev)
1159{
1160	enum mctrl_gpio_idx i;
1161	struct gpio_desc *gpiod;
1162
1163	s->gpios = mctrl_gpio_init(dev, 0);
1164	if (IS_ERR(s->gpios))
1165		return PTR_ERR(s->gpios);
1166
1167	/* Block (enabled before) DMA option if RTS or CTS is GPIO line */
1168	if (!RTS_AT_AUART() || !CTS_AT_AUART()) {
1169		if (test_bit(MXS_AUART_RTSCTS, &s->flags))
1170			dev_warn(dev,
1171				 "DMA and flow control via gpio may cause some problems. DMA disabled!\n");
1172		clear_bit(MXS_AUART_RTSCTS, &s->flags);
1173	}
1174
1175	for (i = 0; i < UART_GPIO_MAX; i++) {
1176		gpiod = mctrl_gpio_to_gpiod(s->gpios, i);
1177		if (gpiod && (gpiod_get_direction(gpiod) == GPIOF_DIR_IN))
1178			s->gpio_irq[i] = gpiod_to_irq(gpiod);
1179		else
1180			s->gpio_irq[i] = -EINVAL;
1181	}
1182
1183	return 0;
1184}
1185
1186static void mxs_auart_free_gpio_irq(struct mxs_auart_port *s)
1187{
1188	enum mctrl_gpio_idx i;
1189
1190	for (i = 0; i < UART_GPIO_MAX; i++)
1191		if (s->gpio_irq[i] >= 0)
1192			free_irq(s->gpio_irq[i], s);
1193}
1194
1195static int mxs_auart_request_gpio_irq(struct mxs_auart_port *s)
1196{
1197	int *irq = s->gpio_irq;
1198	enum mctrl_gpio_idx i;
1199	int err = 0;
1200
1201	for (i = 0; (i < UART_GPIO_MAX) && !err; i++) {
1202		if (irq[i] < 0)
1203			continue;
1204
1205		irq_set_status_flags(irq[i], IRQ_NOAUTOEN);
1206		err = request_irq(irq[i], mxs_auart_irq_handle,
1207				IRQ_TYPE_EDGE_BOTH, dev_name(s->dev), s);
1208		if (err)
1209			dev_err(s->dev, "%s - Can't get %d irq\n",
1210				__func__, irq[i]);
1211	}
1212
1213	/*
1214	 * If something went wrong, rollback.
1215	 */
1216	while (err && (--i >= 0))
1217		if (irq[i] >= 0)
1218			free_irq(irq[i], s);
1219
1220	return err;
1221}
1222
1223static int mxs_auart_probe(struct platform_device *pdev)
1224{
1225	const struct of_device_id *of_id =
1226			of_match_device(mxs_auart_dt_ids, &pdev->dev);
1227	struct mxs_auart_port *s;
1228	u32 version;
1229	int ret, irq;
1230	struct resource *r;
1231
1232	s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
1233	if (!s)
1234		return -ENOMEM;
1235
1236	ret = serial_mxs_probe_dt(s, pdev);
1237	if (ret > 0)
1238		s->port.line = pdev->id < 0 ? 0 : pdev->id;
1239	else if (ret < 0)
1240		return ret;
1241
1242	if (of_id) {
1243		pdev->id_entry = of_id->data;
1244		s->devtype = pdev->id_entry->driver_data;
1245	}
1246
1247	s->clk = devm_clk_get(&pdev->dev, NULL);
1248	if (IS_ERR(s->clk))
1249		return PTR_ERR(s->clk);
1250
1251	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1252	if (!r)
1253		return -ENXIO;
1254
1255
1256	s->port.mapbase = r->start;
1257	s->port.membase = ioremap(r->start, resource_size(r));
1258	s->port.ops = &mxs_auart_ops;
1259	s->port.iotype = UPIO_MEM;
1260	s->port.fifosize = MXS_AUART_FIFO_SIZE;
1261	s->port.uartclk = clk_get_rate(s->clk);
1262	s->port.type = PORT_IMX;
1263	s->port.dev = s->dev = &pdev->dev;
1264
1265	s->mctrl_prev = 0;
1266
1267	irq = platform_get_irq(pdev, 0);
1268	if (irq < 0)
1269		return irq;
1270
1271	s->port.irq = irq;
1272	ret = devm_request_irq(&pdev->dev, irq, mxs_auart_irq_handle, 0,
1273			       dev_name(&pdev->dev), s);
1274	if (ret)
1275		return ret;
1276
1277	platform_set_drvdata(pdev, s);
1278
1279	ret = mxs_auart_init_gpios(s, &pdev->dev);
1280	if (ret) {
1281		dev_err(&pdev->dev, "Failed to initialize GPIOs.\n");
1282		return ret;
1283	}
1284
1285	/*
1286	 * Get the GPIO lines IRQ
1287	 */
1288	ret = mxs_auart_request_gpio_irq(s);
1289	if (ret)
1290		return ret;
1291
1292	auart_port[s->port.line] = s;
1293
1294	mxs_auart_reset(&s->port);
1295
1296	ret = uart_add_one_port(&auart_driver, &s->port);
1297	if (ret)
1298		goto out_free_gpio_irq;
1299
1300	version = readl(s->port.membase + AUART_VERSION);
1301	dev_info(&pdev->dev, "Found APPUART %d.%d.%d\n",
1302	       (version >> 24) & 0xff,
1303	       (version >> 16) & 0xff, version & 0xffff);
1304
1305	return 0;
1306
1307out_free_gpio_irq:
1308	mxs_auart_free_gpio_irq(s);
1309	auart_port[pdev->id] = NULL;
1310	return ret;
1311}
1312
1313static int mxs_auart_remove(struct platform_device *pdev)
1314{
1315	struct mxs_auart_port *s = platform_get_drvdata(pdev);
1316
1317	uart_remove_one_port(&auart_driver, &s->port);
1318	auart_port[pdev->id] = NULL;
1319	mxs_auart_free_gpio_irq(s);
1320
1321	return 0;
1322}
1323
1324static struct platform_driver mxs_auart_driver = {
1325	.probe = mxs_auart_probe,
1326	.remove = mxs_auart_remove,
1327	.driver = {
1328		.name = "mxs-auart",
1329		.of_match_table = mxs_auart_dt_ids,
1330	},
1331};
1332
1333static int __init mxs_auart_init(void)
1334{
1335	int r;
1336
1337	r = uart_register_driver(&auart_driver);
1338	if (r)
1339		goto out;
1340
1341	r = platform_driver_register(&mxs_auart_driver);
1342	if (r)
1343		goto out_err;
1344
1345	return 0;
1346out_err:
1347	uart_unregister_driver(&auart_driver);
1348out:
1349	return r;
1350}
1351
1352static void __exit mxs_auart_exit(void)
1353{
1354	platform_driver_unregister(&mxs_auart_driver);
1355	uart_unregister_driver(&auart_driver);
1356}
1357
1358module_init(mxs_auart_init);
1359module_exit(mxs_auart_exit);
1360MODULE_LICENSE("GPL");
1361MODULE_DESCRIPTION("Freescale MXS application uart driver");
1362MODULE_ALIAS("platform:mxs-auart");
1363