[go: nahoru, domu]

1/*
2 * MOXA ART SoCs DMA Engine support.
3 *
4 * Copyright (C) 2013 Jonas Jensen
5 *
6 * Jonas Jensen <jonas.jensen@gmail.com>
7 *
8 * This file is licensed under the terms of the GNU General Public
9 * License version 2.  This program is licensed "as is" without any
10 * warranty of any kind, whether express or implied.
11 */
12
13#include <linux/dmaengine.h>
14#include <linux/dma-mapping.h>
15#include <linux/err.h>
16#include <linux/init.h>
17#include <linux/interrupt.h>
18#include <linux/list.h>
19#include <linux/module.h>
20#include <linux/platform_device.h>
21#include <linux/slab.h>
22#include <linux/spinlock.h>
23#include <linux/of_address.h>
24#include <linux/of_irq.h>
25#include <linux/of_dma.h>
26#include <linux/bitops.h>
27
28#include <asm/cacheflush.h>
29
30#include "dmaengine.h"
31#include "virt-dma.h"
32
33#define APB_DMA_MAX_CHANNEL			4
34
35#define REG_OFF_ADDRESS_SOURCE			0
36#define REG_OFF_ADDRESS_DEST			4
37#define REG_OFF_CYCLES				8
38#define REG_OFF_CTRL				12
39#define REG_OFF_CHAN_SIZE			16
40
41#define APB_DMA_ENABLE				BIT(0)
42#define APB_DMA_FIN_INT_STS			BIT(1)
43#define APB_DMA_FIN_INT_EN			BIT(2)
44#define APB_DMA_BURST_MODE			BIT(3)
45#define APB_DMA_ERR_INT_STS			BIT(4)
46#define APB_DMA_ERR_INT_EN			BIT(5)
47
48/*
49 * Unset: APB
50 * Set:   AHB
51 */
52#define APB_DMA_SOURCE_SELECT			0x40
53#define APB_DMA_DEST_SELECT			0x80
54
55#define APB_DMA_SOURCE				0x100
56#define APB_DMA_DEST				0x1000
57
58#define APB_DMA_SOURCE_MASK			0x700
59#define APB_DMA_DEST_MASK			0x7000
60
61/*
62 * 000: No increment
63 * 001: +1 (Burst=0), +4  (Burst=1)
64 * 010: +2 (Burst=0), +8  (Burst=1)
65 * 011: +4 (Burst=0), +16 (Burst=1)
66 * 101: -1 (Burst=0), -4  (Burst=1)
67 * 110: -2 (Burst=0), -8  (Burst=1)
68 * 111: -4 (Burst=0), -16 (Burst=1)
69 */
70#define APB_DMA_SOURCE_INC_0			0
71#define APB_DMA_SOURCE_INC_1_4			0x100
72#define APB_DMA_SOURCE_INC_2_8			0x200
73#define APB_DMA_SOURCE_INC_4_16			0x300
74#define APB_DMA_SOURCE_DEC_1_4			0x500
75#define APB_DMA_SOURCE_DEC_2_8			0x600
76#define APB_DMA_SOURCE_DEC_4_16			0x700
77#define APB_DMA_DEST_INC_0			0
78#define APB_DMA_DEST_INC_1_4			0x1000
79#define APB_DMA_DEST_INC_2_8			0x2000
80#define APB_DMA_DEST_INC_4_16			0x3000
81#define APB_DMA_DEST_DEC_1_4			0x5000
82#define APB_DMA_DEST_DEC_2_8			0x6000
83#define APB_DMA_DEST_DEC_4_16			0x7000
84
85/*
86 * Request signal select source/destination address for DMA hardware handshake.
87 *
88 * The request line number is a property of the DMA controller itself,
89 * e.g. MMC must always request channels where dma_slave_config->slave_id is 5.
90 *
91 * 0:    No request / Grant signal
92 * 1-15: Request    / Grant signal
93 */
94#define APB_DMA_SOURCE_REQ_NO			0x1000000
95#define APB_DMA_SOURCE_REQ_NO_MASK		0xf000000
96#define APB_DMA_DEST_REQ_NO			0x10000
97#define APB_DMA_DEST_REQ_NO_MASK		0xf0000
98
99#define APB_DMA_DATA_WIDTH			0x100000
100#define APB_DMA_DATA_WIDTH_MASK			0x300000
101/*
102 * Data width of transfer:
103 *
104 * 00: Word
105 * 01: Half
106 * 10: Byte
107 */
108#define APB_DMA_DATA_WIDTH_4			0
109#define APB_DMA_DATA_WIDTH_2			0x100000
110#define APB_DMA_DATA_WIDTH_1			0x200000
111
112#define APB_DMA_CYCLES_MASK			0x00ffffff
113
114#define MOXART_DMA_DATA_TYPE_S8			0x00
115#define MOXART_DMA_DATA_TYPE_S16		0x01
116#define MOXART_DMA_DATA_TYPE_S32		0x02
117
118struct moxart_sg {
119	dma_addr_t addr;
120	uint32_t len;
121};
122
123struct moxart_desc {
124	enum dma_transfer_direction	dma_dir;
125	dma_addr_t			dev_addr;
126	unsigned int			sglen;
127	unsigned int			dma_cycles;
128	struct virt_dma_desc		vd;
129	uint8_t				es;
130	struct moxart_sg		sg[0];
131};
132
133struct moxart_chan {
134	struct virt_dma_chan		vc;
135
136	void __iomem			*base;
137	struct moxart_desc		*desc;
138
139	struct dma_slave_config		cfg;
140
141	bool				allocated;
142	bool				error;
143	int				ch_num;
144	unsigned int			line_reqno;
145	unsigned int			sgidx;
146};
147
148struct moxart_dmadev {
149	struct dma_device		dma_slave;
150	struct moxart_chan		slave_chans[APB_DMA_MAX_CHANNEL];
151};
152
153struct moxart_filter_data {
154	struct moxart_dmadev		*mdc;
155	struct of_phandle_args		*dma_spec;
156};
157
158static const unsigned int es_bytes[] = {
159	[MOXART_DMA_DATA_TYPE_S8] = 1,
160	[MOXART_DMA_DATA_TYPE_S16] = 2,
161	[MOXART_DMA_DATA_TYPE_S32] = 4,
162};
163
164static struct device *chan2dev(struct dma_chan *chan)
165{
166	return &chan->dev->device;
167}
168
169static inline struct moxart_chan *to_moxart_dma_chan(struct dma_chan *c)
170{
171	return container_of(c, struct moxart_chan, vc.chan);
172}
173
174static inline struct moxart_desc *to_moxart_dma_desc(
175	struct dma_async_tx_descriptor *t)
176{
177	return container_of(t, struct moxart_desc, vd.tx);
178}
179
180static void moxart_dma_desc_free(struct virt_dma_desc *vd)
181{
182	kfree(container_of(vd, struct moxart_desc, vd));
183}
184
185static int moxart_terminate_all(struct dma_chan *chan)
186{
187	struct moxart_chan *ch = to_moxart_dma_chan(chan);
188	unsigned long flags;
189	LIST_HEAD(head);
190	u32 ctrl;
191
192	dev_dbg(chan2dev(chan), "%s: ch=%p\n", __func__, ch);
193
194	spin_lock_irqsave(&ch->vc.lock, flags);
195
196	if (ch->desc)
197		ch->desc = NULL;
198
199	ctrl = readl(ch->base + REG_OFF_CTRL);
200	ctrl &= ~(APB_DMA_ENABLE | APB_DMA_FIN_INT_EN | APB_DMA_ERR_INT_EN);
201	writel(ctrl, ch->base + REG_OFF_CTRL);
202
203	vchan_get_all_descriptors(&ch->vc, &head);
204	spin_unlock_irqrestore(&ch->vc.lock, flags);
205	vchan_dma_desc_free_list(&ch->vc, &head);
206
207	return 0;
208}
209
210static int moxart_slave_config(struct dma_chan *chan,
211			       struct dma_slave_config *cfg)
212{
213	struct moxart_chan *ch = to_moxart_dma_chan(chan);
214	u32 ctrl;
215
216	ch->cfg = *cfg;
217
218	ctrl = readl(ch->base + REG_OFF_CTRL);
219	ctrl |= APB_DMA_BURST_MODE;
220	ctrl &= ~(APB_DMA_DEST_MASK | APB_DMA_SOURCE_MASK);
221	ctrl &= ~(APB_DMA_DEST_REQ_NO_MASK | APB_DMA_SOURCE_REQ_NO_MASK);
222
223	switch (ch->cfg.src_addr_width) {
224	case DMA_SLAVE_BUSWIDTH_1_BYTE:
225		ctrl |= APB_DMA_DATA_WIDTH_1;
226		if (ch->cfg.direction != DMA_MEM_TO_DEV)
227			ctrl |= APB_DMA_DEST_INC_1_4;
228		else
229			ctrl |= APB_DMA_SOURCE_INC_1_4;
230		break;
231	case DMA_SLAVE_BUSWIDTH_2_BYTES:
232		ctrl |= APB_DMA_DATA_WIDTH_2;
233		if (ch->cfg.direction != DMA_MEM_TO_DEV)
234			ctrl |= APB_DMA_DEST_INC_2_8;
235		else
236			ctrl |= APB_DMA_SOURCE_INC_2_8;
237		break;
238	case DMA_SLAVE_BUSWIDTH_4_BYTES:
239		ctrl &= ~APB_DMA_DATA_WIDTH;
240		if (ch->cfg.direction != DMA_MEM_TO_DEV)
241			ctrl |= APB_DMA_DEST_INC_4_16;
242		else
243			ctrl |= APB_DMA_SOURCE_INC_4_16;
244		break;
245	default:
246		return -EINVAL;
247	}
248
249	if (ch->cfg.direction == DMA_MEM_TO_DEV) {
250		ctrl &= ~APB_DMA_DEST_SELECT;
251		ctrl |= APB_DMA_SOURCE_SELECT;
252		ctrl |= (ch->line_reqno << 16 &
253			 APB_DMA_DEST_REQ_NO_MASK);
254	} else {
255		ctrl |= APB_DMA_DEST_SELECT;
256		ctrl &= ~APB_DMA_SOURCE_SELECT;
257		ctrl |= (ch->line_reqno << 24 &
258			 APB_DMA_SOURCE_REQ_NO_MASK);
259	}
260
261	writel(ctrl, ch->base + REG_OFF_CTRL);
262
263	return 0;
264}
265
266static int moxart_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
267			  unsigned long arg)
268{
269	int ret = 0;
270
271	switch (cmd) {
272	case DMA_PAUSE:
273	case DMA_RESUME:
274		return -EINVAL;
275	case DMA_TERMINATE_ALL:
276		moxart_terminate_all(chan);
277		break;
278	case DMA_SLAVE_CONFIG:
279		ret = moxart_slave_config(chan, (struct dma_slave_config *)arg);
280		break;
281	default:
282		ret = -ENOSYS;
283	}
284
285	return ret;
286}
287
288static struct dma_async_tx_descriptor *moxart_prep_slave_sg(
289	struct dma_chan *chan, struct scatterlist *sgl,
290	unsigned int sg_len, enum dma_transfer_direction dir,
291	unsigned long tx_flags, void *context)
292{
293	struct moxart_chan *ch = to_moxart_dma_chan(chan);
294	struct moxart_desc *d;
295	enum dma_slave_buswidth dev_width;
296	dma_addr_t dev_addr;
297	struct scatterlist *sgent;
298	unsigned int es;
299	unsigned int i;
300
301	if (!is_slave_direction(dir)) {
302		dev_err(chan2dev(chan), "%s: invalid DMA direction\n",
303			__func__);
304		return NULL;
305	}
306
307	if (dir == DMA_DEV_TO_MEM) {
308		dev_addr = ch->cfg.src_addr;
309		dev_width = ch->cfg.src_addr_width;
310	} else {
311		dev_addr = ch->cfg.dst_addr;
312		dev_width = ch->cfg.dst_addr_width;
313	}
314
315	switch (dev_width) {
316	case DMA_SLAVE_BUSWIDTH_1_BYTE:
317		es = MOXART_DMA_DATA_TYPE_S8;
318		break;
319	case DMA_SLAVE_BUSWIDTH_2_BYTES:
320		es = MOXART_DMA_DATA_TYPE_S16;
321		break;
322	case DMA_SLAVE_BUSWIDTH_4_BYTES:
323		es = MOXART_DMA_DATA_TYPE_S32;
324		break;
325	default:
326		dev_err(chan2dev(chan), "%s: unsupported data width (%u)\n",
327			__func__, dev_width);
328		return NULL;
329	}
330
331	d = kzalloc(sizeof(*d) + sg_len * sizeof(d->sg[0]), GFP_ATOMIC);
332	if (!d)
333		return NULL;
334
335	d->dma_dir = dir;
336	d->dev_addr = dev_addr;
337	d->es = es;
338
339	for_each_sg(sgl, sgent, sg_len, i) {
340		d->sg[i].addr = sg_dma_address(sgent);
341		d->sg[i].len = sg_dma_len(sgent);
342	}
343
344	d->sglen = sg_len;
345
346	ch->error = 0;
347
348	return vchan_tx_prep(&ch->vc, &d->vd, tx_flags);
349}
350
351static struct dma_chan *moxart_of_xlate(struct of_phandle_args *dma_spec,
352					struct of_dma *ofdma)
353{
354	struct moxart_dmadev *mdc = ofdma->of_dma_data;
355	struct dma_chan *chan;
356	struct moxart_chan *ch;
357
358	chan = dma_get_any_slave_channel(&mdc->dma_slave);
359	if (!chan)
360		return NULL;
361
362	ch = to_moxart_dma_chan(chan);
363	ch->line_reqno = dma_spec->args[0];
364
365	return chan;
366}
367
368static int moxart_alloc_chan_resources(struct dma_chan *chan)
369{
370	struct moxart_chan *ch = to_moxart_dma_chan(chan);
371
372	dev_dbg(chan2dev(chan), "%s: allocating channel #%u\n",
373		__func__, ch->ch_num);
374	ch->allocated = 1;
375
376	return 0;
377}
378
379static void moxart_free_chan_resources(struct dma_chan *chan)
380{
381	struct moxart_chan *ch = to_moxart_dma_chan(chan);
382
383	vchan_free_chan_resources(&ch->vc);
384
385	dev_dbg(chan2dev(chan), "%s: freeing channel #%u\n",
386		__func__, ch->ch_num);
387	ch->allocated = 0;
388}
389
390static void moxart_dma_set_params(struct moxart_chan *ch, dma_addr_t src_addr,
391				  dma_addr_t dst_addr)
392{
393	writel(src_addr, ch->base + REG_OFF_ADDRESS_SOURCE);
394	writel(dst_addr, ch->base + REG_OFF_ADDRESS_DEST);
395}
396
397static void moxart_set_transfer_params(struct moxart_chan *ch, unsigned int len)
398{
399	struct moxart_desc *d = ch->desc;
400	unsigned int sglen_div = es_bytes[d->es];
401
402	d->dma_cycles = len >> sglen_div;
403
404	/*
405	 * There are 4 cycles on 64 bytes copied, i.e. one cycle copies 16
406	 * bytes ( when width is APB_DMAB_DATA_WIDTH_4 ).
407	 */
408	writel(d->dma_cycles, ch->base + REG_OFF_CYCLES);
409
410	dev_dbg(chan2dev(&ch->vc.chan), "%s: set %u DMA cycles (len=%u)\n",
411		__func__, d->dma_cycles, len);
412}
413
414static void moxart_start_dma(struct moxart_chan *ch)
415{
416	u32 ctrl;
417
418	ctrl = readl(ch->base + REG_OFF_CTRL);
419	ctrl |= (APB_DMA_ENABLE | APB_DMA_FIN_INT_EN | APB_DMA_ERR_INT_EN);
420	writel(ctrl, ch->base + REG_OFF_CTRL);
421}
422
423static void moxart_dma_start_sg(struct moxart_chan *ch, unsigned int idx)
424{
425	struct moxart_desc *d = ch->desc;
426	struct moxart_sg *sg = ch->desc->sg + idx;
427
428	if (ch->desc->dma_dir == DMA_MEM_TO_DEV)
429		moxart_dma_set_params(ch, sg->addr, d->dev_addr);
430	else if (ch->desc->dma_dir == DMA_DEV_TO_MEM)
431		moxart_dma_set_params(ch, d->dev_addr, sg->addr);
432
433	moxart_set_transfer_params(ch, sg->len);
434
435	moxart_start_dma(ch);
436}
437
438static void moxart_dma_start_desc(struct dma_chan *chan)
439{
440	struct moxart_chan *ch = to_moxart_dma_chan(chan);
441	struct virt_dma_desc *vd;
442
443	vd = vchan_next_desc(&ch->vc);
444
445	if (!vd) {
446		ch->desc = NULL;
447		return;
448	}
449
450	list_del(&vd->node);
451
452	ch->desc = to_moxart_dma_desc(&vd->tx);
453	ch->sgidx = 0;
454
455	moxart_dma_start_sg(ch, 0);
456}
457
458static void moxart_issue_pending(struct dma_chan *chan)
459{
460	struct moxart_chan *ch = to_moxart_dma_chan(chan);
461	unsigned long flags;
462
463	spin_lock_irqsave(&ch->vc.lock, flags);
464	if (vchan_issue_pending(&ch->vc) && !ch->desc)
465		moxart_dma_start_desc(chan);
466	spin_unlock_irqrestore(&ch->vc.lock, flags);
467}
468
469static size_t moxart_dma_desc_size(struct moxart_desc *d,
470				   unsigned int completed_sgs)
471{
472	unsigned int i;
473	size_t size;
474
475	for (size = i = completed_sgs; i < d->sglen; i++)
476		size += d->sg[i].len;
477
478	return size;
479}
480
481static size_t moxart_dma_desc_size_in_flight(struct moxart_chan *ch)
482{
483	size_t size;
484	unsigned int completed_cycles, cycles;
485
486	size = moxart_dma_desc_size(ch->desc, ch->sgidx);
487	cycles = readl(ch->base + REG_OFF_CYCLES);
488	completed_cycles = (ch->desc->dma_cycles - cycles);
489	size -= completed_cycles << es_bytes[ch->desc->es];
490
491	dev_dbg(chan2dev(&ch->vc.chan), "%s: size=%zu\n", __func__, size);
492
493	return size;
494}
495
496static enum dma_status moxart_tx_status(struct dma_chan *chan,
497					dma_cookie_t cookie,
498					struct dma_tx_state *txstate)
499{
500	struct moxart_chan *ch = to_moxart_dma_chan(chan);
501	struct virt_dma_desc *vd;
502	struct moxart_desc *d;
503	enum dma_status ret;
504	unsigned long flags;
505
506	/*
507	 * dma_cookie_status() assigns initial residue value.
508	 */
509	ret = dma_cookie_status(chan, cookie, txstate);
510
511	spin_lock_irqsave(&ch->vc.lock, flags);
512	vd = vchan_find_desc(&ch->vc, cookie);
513	if (vd) {
514		d = to_moxart_dma_desc(&vd->tx);
515		txstate->residue = moxart_dma_desc_size(d, 0);
516	} else if (ch->desc && ch->desc->vd.tx.cookie == cookie) {
517		txstate->residue = moxart_dma_desc_size_in_flight(ch);
518	}
519	spin_unlock_irqrestore(&ch->vc.lock, flags);
520
521	if (ch->error)
522		return DMA_ERROR;
523
524	return ret;
525}
526
527static void moxart_dma_init(struct dma_device *dma, struct device *dev)
528{
529	dma->device_prep_slave_sg		= moxart_prep_slave_sg;
530	dma->device_alloc_chan_resources	= moxart_alloc_chan_resources;
531	dma->device_free_chan_resources		= moxart_free_chan_resources;
532	dma->device_issue_pending		= moxart_issue_pending;
533	dma->device_tx_status			= moxart_tx_status;
534	dma->device_control			= moxart_control;
535	dma->dev				= dev;
536
537	INIT_LIST_HEAD(&dma->channels);
538}
539
540static irqreturn_t moxart_dma_interrupt(int irq, void *devid)
541{
542	struct moxart_dmadev *mc = devid;
543	struct moxart_chan *ch = &mc->slave_chans[0];
544	unsigned int i;
545	unsigned long flags;
546	u32 ctrl;
547
548	dev_dbg(chan2dev(&ch->vc.chan), "%s\n", __func__);
549
550	for (i = 0; i < APB_DMA_MAX_CHANNEL; i++, ch++) {
551		if (!ch->allocated)
552			continue;
553
554		ctrl = readl(ch->base + REG_OFF_CTRL);
555
556		dev_dbg(chan2dev(&ch->vc.chan), "%s: ch=%p ch->base=%p ctrl=%x\n",
557			__func__, ch, ch->base, ctrl);
558
559		if (ctrl & APB_DMA_FIN_INT_STS) {
560			ctrl &= ~APB_DMA_FIN_INT_STS;
561			if (ch->desc) {
562				spin_lock_irqsave(&ch->vc.lock, flags);
563				if (++ch->sgidx < ch->desc->sglen) {
564					moxart_dma_start_sg(ch, ch->sgidx);
565				} else {
566					vchan_cookie_complete(&ch->desc->vd);
567					moxart_dma_start_desc(&ch->vc.chan);
568				}
569				spin_unlock_irqrestore(&ch->vc.lock, flags);
570			}
571		}
572
573		if (ctrl & APB_DMA_ERR_INT_STS) {
574			ctrl &= ~APB_DMA_ERR_INT_STS;
575			ch->error = 1;
576		}
577
578		writel(ctrl, ch->base + REG_OFF_CTRL);
579	}
580
581	return IRQ_HANDLED;
582}
583
584static int moxart_probe(struct platform_device *pdev)
585{
586	struct device *dev = &pdev->dev;
587	struct device_node *node = dev->of_node;
588	struct resource *res;
589	static void __iomem *dma_base_addr;
590	int ret, i;
591	unsigned int irq;
592	struct moxart_chan *ch;
593	struct moxart_dmadev *mdc;
594
595	mdc = devm_kzalloc(dev, sizeof(*mdc), GFP_KERNEL);
596	if (!mdc) {
597		dev_err(dev, "can't allocate DMA container\n");
598		return -ENOMEM;
599	}
600
601	irq = irq_of_parse_and_map(node, 0);
602	if (irq == NO_IRQ) {
603		dev_err(dev, "no IRQ resource\n");
604		return -EINVAL;
605	}
606
607	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
608	dma_base_addr = devm_ioremap_resource(dev, res);
609	if (IS_ERR(dma_base_addr))
610		return PTR_ERR(dma_base_addr);
611
612	dma_cap_zero(mdc->dma_slave.cap_mask);
613	dma_cap_set(DMA_SLAVE, mdc->dma_slave.cap_mask);
614	dma_cap_set(DMA_PRIVATE, mdc->dma_slave.cap_mask);
615
616	moxart_dma_init(&mdc->dma_slave, dev);
617
618	ch = &mdc->slave_chans[0];
619	for (i = 0; i < APB_DMA_MAX_CHANNEL; i++, ch++) {
620		ch->ch_num = i;
621		ch->base = dma_base_addr + i * REG_OFF_CHAN_SIZE;
622		ch->allocated = 0;
623
624		ch->vc.desc_free = moxart_dma_desc_free;
625		vchan_init(&ch->vc, &mdc->dma_slave);
626
627		dev_dbg(dev, "%s: chs[%d]: ch->ch_num=%u ch->base=%p\n",
628			__func__, i, ch->ch_num, ch->base);
629	}
630
631	platform_set_drvdata(pdev, mdc);
632
633	ret = devm_request_irq(dev, irq, moxart_dma_interrupt, 0,
634			       "moxart-dma-engine", mdc);
635	if (ret) {
636		dev_err(dev, "devm_request_irq failed\n");
637		return ret;
638	}
639
640	ret = dma_async_device_register(&mdc->dma_slave);
641	if (ret) {
642		dev_err(dev, "dma_async_device_register failed\n");
643		return ret;
644	}
645
646	ret = of_dma_controller_register(node, moxart_of_xlate, mdc);
647	if (ret) {
648		dev_err(dev, "of_dma_controller_register failed\n");
649		dma_async_device_unregister(&mdc->dma_slave);
650		return ret;
651	}
652
653	dev_dbg(dev, "%s: IRQ=%u\n", __func__, irq);
654
655	return 0;
656}
657
658static int moxart_remove(struct platform_device *pdev)
659{
660	struct moxart_dmadev *m = platform_get_drvdata(pdev);
661
662	dma_async_device_unregister(&m->dma_slave);
663
664	if (pdev->dev.of_node)
665		of_dma_controller_free(pdev->dev.of_node);
666
667	return 0;
668}
669
670static const struct of_device_id moxart_dma_match[] = {
671	{ .compatible = "moxa,moxart-dma" },
672	{ }
673};
674
675static struct platform_driver moxart_driver = {
676	.probe	= moxart_probe,
677	.remove	= moxart_remove,
678	.driver = {
679		.name		= "moxart-dma-engine",
680		.owner		= THIS_MODULE,
681		.of_match_table	= moxart_dma_match,
682	},
683};
684
685static int moxart_init(void)
686{
687	return platform_driver_register(&moxart_driver);
688}
689subsys_initcall(moxart_init);
690
691static void __exit moxart_exit(void)
692{
693	platform_driver_unregister(&moxart_driver);
694}
695module_exit(moxart_exit);
696
697MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>");
698MODULE_DESCRIPTION("MOXART DMA engine driver");
699MODULE_LICENSE("GPL v2");
700