1// SPDX-License-Identifier: GPL-2.0+
2//
3// drivers/dma/imx-dma.c
4//
5// This file contains a driver for the Freescale i.MX DMA engine
6// found on i.MX1/21/27
7//
8// Copyright 2010 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
9// Copyright 2012 Javier Martin, Vista Silicon <javier.martin@vista-silicon.com>
10
11#include <linux/err.h>
12#include <linux/init.h>
13#include <linux/types.h>
14#include <linux/mm.h>
15#include <linux/interrupt.h>
16#include <linux/spinlock.h>
17#include <linux/device.h>
18#include <linux/dma-mapping.h>
19#include <linux/slab.h>
20#include <linux/platform_device.h>
21#include <linux/clk.h>
22#include <linux/dmaengine.h>
23#include <linux/module.h>
24#include <linux/of.h>
25#include <linux/of_dma.h>
26
27#include <asm/irq.h>
28#include <linux/dma/imx-dma.h>
29
30#include "dmaengine.h"
31#define IMXDMA_MAX_CHAN_DESCRIPTORS	16
32#define IMX_DMA_CHANNELS  16
33
34#define IMX_DMA_2D_SLOTS	2
35#define IMX_DMA_2D_SLOT_A	0
36#define IMX_DMA_2D_SLOT_B	1
37
38#define IMX_DMA_LENGTH_LOOP	((unsigned int)-1)
39#define IMX_DMA_MEMSIZE_32	(0 << 4)
40#define IMX_DMA_MEMSIZE_8	(1 << 4)
41#define IMX_DMA_MEMSIZE_16	(2 << 4)
42#define IMX_DMA_TYPE_LINEAR	(0 << 10)
43#define IMX_DMA_TYPE_2D		(1 << 10)
44#define IMX_DMA_TYPE_FIFO	(2 << 10)
45
46#define IMX_DMA_ERR_BURST     (1 << 0)
47#define IMX_DMA_ERR_REQUEST   (1 << 1)
48#define IMX_DMA_ERR_TRANSFER  (1 << 2)
49#define IMX_DMA_ERR_BUFFER    (1 << 3)
50#define IMX_DMA_ERR_TIMEOUT   (1 << 4)
51
52#define DMA_DCR     0x00		/* Control Register */
53#define DMA_DISR    0x04		/* Interrupt status Register */
54#define DMA_DIMR    0x08		/* Interrupt mask Register */
55#define DMA_DBTOSR  0x0c		/* Burst timeout status Register */
56#define DMA_DRTOSR  0x10		/* Request timeout Register */
57#define DMA_DSESR   0x14		/* Transfer Error Status Register */
58#define DMA_DBOSR   0x18		/* Buffer overflow status Register */
59#define DMA_DBTOCR  0x1c		/* Burst timeout control Register */
60#define DMA_WSRA    0x40		/* W-Size Register A */
61#define DMA_XSRA    0x44		/* X-Size Register A */
62#define DMA_YSRA    0x48		/* Y-Size Register A */
63#define DMA_WSRB    0x4c		/* W-Size Register B */
64#define DMA_XSRB    0x50		/* X-Size Register B */
65#define DMA_YSRB    0x54		/* Y-Size Register B */
66#define DMA_SAR(x)  (0x80 + ((x) << 6))	/* Source Address Registers */
67#define DMA_DAR(x)  (0x84 + ((x) << 6))	/* Destination Address Registers */
68#define DMA_CNTR(x) (0x88 + ((x) << 6))	/* Count Registers */
69#define DMA_CCR(x)  (0x8c + ((x) << 6))	/* Control Registers */
70#define DMA_RSSR(x) (0x90 + ((x) << 6))	/* Request source select Registers */
71#define DMA_BLR(x)  (0x94 + ((x) << 6))	/* Burst length Registers */
72#define DMA_RTOR(x) (0x98 + ((x) << 6))	/* Request timeout Registers */
73#define DMA_BUCR(x) (0x98 + ((x) << 6))	/* Bus Utilization Registers */
74#define DMA_CCNR(x) (0x9C + ((x) << 6))	/* Channel counter Registers */
75
76#define DCR_DRST           (1<<1)
77#define DCR_DEN            (1<<0)
78#define DBTOCR_EN          (1<<15)
79#define DBTOCR_CNT(x)      ((x) & 0x7fff)
80#define CNTR_CNT(x)        ((x) & 0xffffff)
81#define CCR_ACRPT          (1<<14)
82#define CCR_DMOD_LINEAR    (0x0 << 12)
83#define CCR_DMOD_2D        (0x1 << 12)
84#define CCR_DMOD_FIFO      (0x2 << 12)
85#define CCR_DMOD_EOBFIFO   (0x3 << 12)
86#define CCR_SMOD_LINEAR    (0x0 << 10)
87#define CCR_SMOD_2D        (0x1 << 10)
88#define CCR_SMOD_FIFO      (0x2 << 10)
89#define CCR_SMOD_EOBFIFO   (0x3 << 10)
90#define CCR_MDIR_DEC       (1<<9)
91#define CCR_MSEL_B         (1<<8)
92#define CCR_DSIZ_32        (0x0 << 6)
93#define CCR_DSIZ_8         (0x1 << 6)
94#define CCR_DSIZ_16        (0x2 << 6)
95#define CCR_SSIZ_32        (0x0 << 4)
96#define CCR_SSIZ_8         (0x1 << 4)
97#define CCR_SSIZ_16        (0x2 << 4)
98#define CCR_REN            (1<<3)
99#define CCR_RPT            (1<<2)
100#define CCR_FRC            (1<<1)
101#define CCR_CEN            (1<<0)
102#define RTOR_EN            (1<<15)
103#define RTOR_CLK           (1<<14)
104#define RTOR_PSC           (1<<13)
105
106enum  imxdma_prep_type {
107	IMXDMA_DESC_MEMCPY,
108	IMXDMA_DESC_INTERLEAVED,
109	IMXDMA_DESC_SLAVE_SG,
110	IMXDMA_DESC_CYCLIC,
111};
112
113struct imx_dma_2d_config {
114	u16		xsr;
115	u16		ysr;
116	u16		wsr;
117	int		count;
118};
119
120struct imxdma_desc {
121	struct list_head		node;
122	struct dma_async_tx_descriptor	desc;
123	enum dma_status			status;
124	dma_addr_t			src;
125	dma_addr_t			dest;
126	size_t				len;
127	enum dma_transfer_direction	direction;
128	enum imxdma_prep_type		type;
129	/* For memcpy and interleaved */
130	unsigned int			config_port;
131	unsigned int			config_mem;
132	/* For interleaved transfers */
133	unsigned int			x;
134	unsigned int			y;
135	unsigned int			w;
136	/* For slave sg and cyclic */
137	struct scatterlist		*sg;
138	unsigned int			sgcount;
139};
140
141struct imxdma_channel {
142	int				hw_chaining;
143	struct timer_list		watchdog;
144	struct imxdma_engine		*imxdma;
145	unsigned int			channel;
146
147	struct tasklet_struct		dma_tasklet;
148	struct list_head		ld_free;
149	struct list_head		ld_queue;
150	struct list_head		ld_active;
151	int				descs_allocated;
152	enum dma_slave_buswidth		word_size;
153	dma_addr_t			per_address;
154	u32				watermark_level;
155	struct dma_chan			chan;
156	struct dma_async_tx_descriptor	desc;
157	enum dma_status			status;
158	int				dma_request;
159	struct scatterlist		*sg_list;
160	u32				ccr_from_device;
161	u32				ccr_to_device;
162	bool				enabled_2d;
163	int				slot_2d;
164	unsigned int			irq;
165	struct dma_slave_config		config;
166};
167
168enum imx_dma_type {
169	IMX1_DMA,
170	IMX21_DMA,
171	IMX27_DMA,
172};
173
174struct imxdma_engine {
175	struct device			*dev;
176	struct dma_device		dma_device;
177	void __iomem			*base;
178	struct clk			*dma_ahb;
179	struct clk			*dma_ipg;
180	spinlock_t			lock;
181	struct imx_dma_2d_config	slots_2d[IMX_DMA_2D_SLOTS];
182	struct imxdma_channel		channel[IMX_DMA_CHANNELS];
183	enum imx_dma_type		devtype;
184	unsigned int			irq;
185	unsigned int			irq_err;
186
187};
188
189struct imxdma_filter_data {
190	struct imxdma_engine	*imxdma;
191	int			 request;
192};
193
194static const struct of_device_id imx_dma_of_dev_id[] = {
195	{
196		.compatible = "fsl,imx1-dma", .data = (const void *)IMX1_DMA,
197	}, {
198		.compatible = "fsl,imx21-dma", .data = (const void *)IMX21_DMA,
199	}, {
200		.compatible = "fsl,imx27-dma", .data = (const void *)IMX27_DMA,
201	}, {
202		/* sentinel */
203	}
204};
205MODULE_DEVICE_TABLE(of, imx_dma_of_dev_id);
206
207static inline int is_imx1_dma(struct imxdma_engine *imxdma)
208{
209	return imxdma->devtype == IMX1_DMA;
210}
211
212static inline int is_imx27_dma(struct imxdma_engine *imxdma)
213{
214	return imxdma->devtype == IMX27_DMA;
215}
216
217static struct imxdma_channel *to_imxdma_chan(struct dma_chan *chan)
218{
219	return container_of(chan, struct imxdma_channel, chan);
220}
221
222static inline bool imxdma_chan_is_doing_cyclic(struct imxdma_channel *imxdmac)
223{
224	struct imxdma_desc *desc;
225
226	if (!list_empty(&imxdmac->ld_active)) {
227		desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc,
228					node);
229		if (desc->type == IMXDMA_DESC_CYCLIC)
230			return true;
231	}
232	return false;
233}
234
235
236
237static void imx_dmav1_writel(struct imxdma_engine *imxdma, unsigned val,
238			     unsigned offset)
239{
240	__raw_writel(val, imxdma->base + offset);
241}
242
243static unsigned imx_dmav1_readl(struct imxdma_engine *imxdma, unsigned offset)
244{
245	return __raw_readl(imxdma->base + offset);
246}
247
248static int imxdma_hw_chain(struct imxdma_channel *imxdmac)
249{
250	struct imxdma_engine *imxdma = imxdmac->imxdma;
251
252	if (is_imx27_dma(imxdma))
253		return imxdmac->hw_chaining;
254	else
255		return 0;
256}
257
258/*
259 * imxdma_sg_next - prepare next chunk for scatter-gather DMA emulation
260 */
261static inline void imxdma_sg_next(struct imxdma_desc *d)
262{
263	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
264	struct imxdma_engine *imxdma = imxdmac->imxdma;
265	struct scatterlist *sg = d->sg;
266	size_t now;
267
268	now = min_t(size_t, d->len, sg_dma_len(sg));
269	if (d->len != IMX_DMA_LENGTH_LOOP)
270		d->len -= now;
271
272	if (d->direction == DMA_DEV_TO_MEM)
273		imx_dmav1_writel(imxdma, sg->dma_address,
274				 DMA_DAR(imxdmac->channel));
275	else
276		imx_dmav1_writel(imxdma, sg->dma_address,
277				 DMA_SAR(imxdmac->channel));
278
279	imx_dmav1_writel(imxdma, now, DMA_CNTR(imxdmac->channel));
280
281	dev_dbg(imxdma->dev, " %s channel: %d dst 0x%08x, src 0x%08x, "
282		"size 0x%08x\n", __func__, imxdmac->channel,
283		 imx_dmav1_readl(imxdma, DMA_DAR(imxdmac->channel)),
284		 imx_dmav1_readl(imxdma, DMA_SAR(imxdmac->channel)),
285		 imx_dmav1_readl(imxdma, DMA_CNTR(imxdmac->channel)));
286}
287
288static void imxdma_enable_hw(struct imxdma_desc *d)
289{
290	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
291	struct imxdma_engine *imxdma = imxdmac->imxdma;
292	int channel = imxdmac->channel;
293	unsigned long flags;
294
295	dev_dbg(imxdma->dev, "%s channel %d\n", __func__, channel);
296
297	local_irq_save(flags);
298
299	imx_dmav1_writel(imxdma, 1 << channel, DMA_DISR);
300	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_DIMR) &
301			 ~(1 << channel), DMA_DIMR);
302	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_CCR(channel)) |
303			 CCR_CEN | CCR_ACRPT, DMA_CCR(channel));
304
305	if (!is_imx1_dma(imxdma) &&
306			d->sg && imxdma_hw_chain(imxdmac)) {
307		d->sg = sg_next(d->sg);
308		if (d->sg) {
309			u32 tmp;
310			imxdma_sg_next(d);
311			tmp = imx_dmav1_readl(imxdma, DMA_CCR(channel));
312			imx_dmav1_writel(imxdma, tmp | CCR_RPT | CCR_ACRPT,
313					 DMA_CCR(channel));
314		}
315	}
316
317	local_irq_restore(flags);
318}
319
320static void imxdma_disable_hw(struct imxdma_channel *imxdmac)
321{
322	struct imxdma_engine *imxdma = imxdmac->imxdma;
323	int channel = imxdmac->channel;
324	unsigned long flags;
325
326	dev_dbg(imxdma->dev, "%s channel %d\n", __func__, channel);
327
328	if (imxdma_hw_chain(imxdmac))
329		del_timer(&imxdmac->watchdog);
330
331	local_irq_save(flags);
332	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_DIMR) |
333			 (1 << channel), DMA_DIMR);
334	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_CCR(channel)) &
335			 ~CCR_CEN, DMA_CCR(channel));
336	imx_dmav1_writel(imxdma, 1 << channel, DMA_DISR);
337	local_irq_restore(flags);
338}
339
340static void imxdma_watchdog(struct timer_list *t)
341{
342	struct imxdma_channel *imxdmac = from_timer(imxdmac, t, watchdog);
343	struct imxdma_engine *imxdma = imxdmac->imxdma;
344	int channel = imxdmac->channel;
345
346	imx_dmav1_writel(imxdma, 0, DMA_CCR(channel));
347
348	/* Tasklet watchdog error handler */
349	tasklet_schedule(&imxdmac->dma_tasklet);
350	dev_dbg(imxdma->dev, "channel %d: watchdog timeout!\n",
351		imxdmac->channel);
352}
353
354static irqreturn_t imxdma_err_handler(int irq, void *dev_id)
355{
356	struct imxdma_engine *imxdma = dev_id;
357	unsigned int err_mask;
358	int i, disr;
359	int errcode;
360
361	disr = imx_dmav1_readl(imxdma, DMA_DISR);
362
363	err_mask = imx_dmav1_readl(imxdma, DMA_DBTOSR) |
364		   imx_dmav1_readl(imxdma, DMA_DRTOSR) |
365		   imx_dmav1_readl(imxdma, DMA_DSESR)  |
366		   imx_dmav1_readl(imxdma, DMA_DBOSR);
367
368	if (!err_mask)
369		return IRQ_HANDLED;
370
371	imx_dmav1_writel(imxdma, disr & err_mask, DMA_DISR);
372
373	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
374		if (!(err_mask & (1 << i)))
375			continue;
376		errcode = 0;
377
378		if (imx_dmav1_readl(imxdma, DMA_DBTOSR) & (1 << i)) {
379			imx_dmav1_writel(imxdma, 1 << i, DMA_DBTOSR);
380			errcode |= IMX_DMA_ERR_BURST;
381		}
382		if (imx_dmav1_readl(imxdma, DMA_DRTOSR) & (1 << i)) {
383			imx_dmav1_writel(imxdma, 1 << i, DMA_DRTOSR);
384			errcode |= IMX_DMA_ERR_REQUEST;
385		}
386		if (imx_dmav1_readl(imxdma, DMA_DSESR) & (1 << i)) {
387			imx_dmav1_writel(imxdma, 1 << i, DMA_DSESR);
388			errcode |= IMX_DMA_ERR_TRANSFER;
389		}
390		if (imx_dmav1_readl(imxdma, DMA_DBOSR) & (1 << i)) {
391			imx_dmav1_writel(imxdma, 1 << i, DMA_DBOSR);
392			errcode |= IMX_DMA_ERR_BUFFER;
393		}
394		/* Tasklet error handler */
395		tasklet_schedule(&imxdma->channel[i].dma_tasklet);
396
397		dev_warn(imxdma->dev,
398			 "DMA timeout on channel %d -%s%s%s%s\n", i,
399			 errcode & IMX_DMA_ERR_BURST ?    " burst" : "",
400			 errcode & IMX_DMA_ERR_REQUEST ?  " request" : "",
401			 errcode & IMX_DMA_ERR_TRANSFER ? " transfer" : "",
402			 errcode & IMX_DMA_ERR_BUFFER ?   " buffer" : "");
403	}
404	return IRQ_HANDLED;
405}
406
407static void dma_irq_handle_channel(struct imxdma_channel *imxdmac)
408{
409	struct imxdma_engine *imxdma = imxdmac->imxdma;
410	int chno = imxdmac->channel;
411	struct imxdma_desc *desc;
412	unsigned long flags;
413
414	spin_lock_irqsave(&imxdma->lock, flags);
415	if (list_empty(&imxdmac->ld_active)) {
416		spin_unlock_irqrestore(&imxdma->lock, flags);
417		goto out;
418	}
419
420	desc = list_first_entry(&imxdmac->ld_active,
421				struct imxdma_desc,
422				node);
423	spin_unlock_irqrestore(&imxdma->lock, flags);
424
425	if (desc->sg) {
426		u32 tmp;
427		desc->sg = sg_next(desc->sg);
428
429		if (desc->sg) {
430			imxdma_sg_next(desc);
431
432			tmp = imx_dmav1_readl(imxdma, DMA_CCR(chno));
433
434			if (imxdma_hw_chain(imxdmac)) {
435				/* FIXME: The timeout should probably be
436				 * configurable
437				 */
438				mod_timer(&imxdmac->watchdog,
439					jiffies + msecs_to_jiffies(500));
440
441				tmp |= CCR_CEN | CCR_RPT | CCR_ACRPT;
442				imx_dmav1_writel(imxdma, tmp, DMA_CCR(chno));
443			} else {
444				imx_dmav1_writel(imxdma, tmp & ~CCR_CEN,
445						 DMA_CCR(chno));
446				tmp |= CCR_CEN;
447			}
448
449			imx_dmav1_writel(imxdma, tmp, DMA_CCR(chno));
450
451			if (imxdma_chan_is_doing_cyclic(imxdmac))
452				/* Tasklet progression */
453				tasklet_schedule(&imxdmac->dma_tasklet);
454
455			return;
456		}
457
458		if (imxdma_hw_chain(imxdmac)) {
459			del_timer(&imxdmac->watchdog);
460			return;
461		}
462	}
463
464out:
465	imx_dmav1_writel(imxdma, 0, DMA_CCR(chno));
466	/* Tasklet irq */
467	tasklet_schedule(&imxdmac->dma_tasklet);
468}
469
470static irqreturn_t dma_irq_handler(int irq, void *dev_id)
471{
472	struct imxdma_engine *imxdma = dev_id;
473	int i, disr;
474
475	if (!is_imx1_dma(imxdma))
476		imxdma_err_handler(irq, dev_id);
477
478	disr = imx_dmav1_readl(imxdma, DMA_DISR);
479
480	dev_dbg(imxdma->dev, "%s called, disr=0x%08x\n", __func__, disr);
481
482	imx_dmav1_writel(imxdma, disr, DMA_DISR);
483	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
484		if (disr & (1 << i))
485			dma_irq_handle_channel(&imxdma->channel[i]);
486	}
487
488	return IRQ_HANDLED;
489}
490
491static int imxdma_xfer_desc(struct imxdma_desc *d)
492{
493	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
494	struct imxdma_engine *imxdma = imxdmac->imxdma;
495	int slot = -1;
496	int i;
497
498	/* Configure and enable */
499	switch (d->type) {
500	case IMXDMA_DESC_INTERLEAVED:
501		/* Try to get a free 2D slot */
502		for (i = 0; i < IMX_DMA_2D_SLOTS; i++) {
503			if ((imxdma->slots_2d[i].count > 0) &&
504			((imxdma->slots_2d[i].xsr != d->x) ||
505			(imxdma->slots_2d[i].ysr != d->y) ||
506			(imxdma->slots_2d[i].wsr != d->w)))
507				continue;
508			slot = i;
509			break;
510		}
511		if (slot < 0)
512			return -EBUSY;
513
514		imxdma->slots_2d[slot].xsr = d->x;
515		imxdma->slots_2d[slot].ysr = d->y;
516		imxdma->slots_2d[slot].wsr = d->w;
517		imxdma->slots_2d[slot].count++;
518
519		imxdmac->slot_2d = slot;
520		imxdmac->enabled_2d = true;
521
522		if (slot == IMX_DMA_2D_SLOT_A) {
523			d->config_mem &= ~CCR_MSEL_B;
524			d->config_port &= ~CCR_MSEL_B;
525			imx_dmav1_writel(imxdma, d->x, DMA_XSRA);
526			imx_dmav1_writel(imxdma, d->y, DMA_YSRA);
527			imx_dmav1_writel(imxdma, d->w, DMA_WSRA);
528		} else {
529			d->config_mem |= CCR_MSEL_B;
530			d->config_port |= CCR_MSEL_B;
531			imx_dmav1_writel(imxdma, d->x, DMA_XSRB);
532			imx_dmav1_writel(imxdma, d->y, DMA_YSRB);
533			imx_dmav1_writel(imxdma, d->w, DMA_WSRB);
534		}
535		/*
536		 * We fall-through here intentionally, since a 2D transfer is
537		 * similar to MEMCPY just adding the 2D slot configuration.
538		 */
539		fallthrough;
540	case IMXDMA_DESC_MEMCPY:
541		imx_dmav1_writel(imxdma, d->src, DMA_SAR(imxdmac->channel));
542		imx_dmav1_writel(imxdma, d->dest, DMA_DAR(imxdmac->channel));
543		imx_dmav1_writel(imxdma, d->config_mem | (d->config_port << 2),
544			 DMA_CCR(imxdmac->channel));
545
546		imx_dmav1_writel(imxdma, d->len, DMA_CNTR(imxdmac->channel));
547
548		dev_dbg(imxdma->dev,
549			"%s channel: %d dest=0x%08llx src=0x%08llx dma_length=%zu\n",
550			__func__, imxdmac->channel,
551			(unsigned long long)d->dest,
552			(unsigned long long)d->src, d->len);
553
554		break;
555	/* Cyclic transfer is the same as slave_sg with special sg configuration. */
556	case IMXDMA_DESC_CYCLIC:
557	case IMXDMA_DESC_SLAVE_SG:
558		if (d->direction == DMA_DEV_TO_MEM) {
559			imx_dmav1_writel(imxdma, imxdmac->per_address,
560					 DMA_SAR(imxdmac->channel));
561			imx_dmav1_writel(imxdma, imxdmac->ccr_from_device,
562					 DMA_CCR(imxdmac->channel));
563
564			dev_dbg(imxdma->dev,
565				"%s channel: %d sg=%p sgcount=%d total length=%zu dev_addr=0x%08llx (dev2mem)\n",
566				__func__, imxdmac->channel,
567				d->sg, d->sgcount, d->len,
568				(unsigned long long)imxdmac->per_address);
569		} else if (d->direction == DMA_MEM_TO_DEV) {
570			imx_dmav1_writel(imxdma, imxdmac->per_address,
571					 DMA_DAR(imxdmac->channel));
572			imx_dmav1_writel(imxdma, imxdmac->ccr_to_device,
573					 DMA_CCR(imxdmac->channel));
574
575			dev_dbg(imxdma->dev,
576				"%s channel: %d sg=%p sgcount=%d total length=%zu dev_addr=0x%08llx (mem2dev)\n",
577				__func__, imxdmac->channel,
578				d->sg, d->sgcount, d->len,
579				(unsigned long long)imxdmac->per_address);
580		} else {
581			dev_err(imxdma->dev, "%s channel: %d bad dma mode\n",
582				__func__, imxdmac->channel);
583			return -EINVAL;
584		}
585
586		imxdma_sg_next(d);
587
588		break;
589	default:
590		return -EINVAL;
591	}
592	imxdma_enable_hw(d);
593	return 0;
594}
595
596static void imxdma_tasklet(struct tasklet_struct *t)
597{
598	struct imxdma_channel *imxdmac = from_tasklet(imxdmac, t, dma_tasklet);
599	struct imxdma_engine *imxdma = imxdmac->imxdma;
600	struct imxdma_desc *desc, *next_desc;
601	unsigned long flags;
602
603	spin_lock_irqsave(&imxdma->lock, flags);
604
605	if (list_empty(&imxdmac->ld_active)) {
606		/* Someone might have called terminate all */
607		spin_unlock_irqrestore(&imxdma->lock, flags);
608		return;
609	}
610	desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc, node);
611
612	/* If we are dealing with a cyclic descriptor, keep it on ld_active
613	 * and dont mark the descriptor as complete.
614	 * Only in non-cyclic cases it would be marked as complete
615	 */
616	if (imxdma_chan_is_doing_cyclic(imxdmac))
617		goto out;
618	else
619		dma_cookie_complete(&desc->desc);
620
621	/* Free 2D slot if it was an interleaved transfer */
622	if (imxdmac->enabled_2d) {
623		imxdma->slots_2d[imxdmac->slot_2d].count--;
624		imxdmac->enabled_2d = false;
625	}
626
627	list_move_tail(imxdmac->ld_active.next, &imxdmac->ld_free);
628
629	if (!list_empty(&imxdmac->ld_queue)) {
630		next_desc = list_first_entry(&imxdmac->ld_queue,
631					     struct imxdma_desc, node);
632		list_move_tail(imxdmac->ld_queue.next, &imxdmac->ld_active);
633		if (imxdma_xfer_desc(next_desc) < 0)
634			dev_warn(imxdma->dev, "%s: channel: %d couldn't xfer desc\n",
635				 __func__, imxdmac->channel);
636	}
637out:
638	spin_unlock_irqrestore(&imxdma->lock, flags);
639
640	dmaengine_desc_get_callback_invoke(&desc->desc, NULL);
641}
642
643static int imxdma_terminate_all(struct dma_chan *chan)
644{
645	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
646	struct imxdma_engine *imxdma = imxdmac->imxdma;
647	unsigned long flags;
648
649	imxdma_disable_hw(imxdmac);
650
651	spin_lock_irqsave(&imxdma->lock, flags);
652	list_splice_tail_init(&imxdmac->ld_active, &imxdmac->ld_free);
653	list_splice_tail_init(&imxdmac->ld_queue, &imxdmac->ld_free);
654	spin_unlock_irqrestore(&imxdma->lock, flags);
655	return 0;
656}
657
658static int imxdma_config_write(struct dma_chan *chan,
659			       struct dma_slave_config *dmaengine_cfg,
660			       enum dma_transfer_direction direction)
661{
662	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
663	struct imxdma_engine *imxdma = imxdmac->imxdma;
664	unsigned int mode = 0;
665
666	if (direction == DMA_DEV_TO_MEM) {
667		imxdmac->per_address = dmaengine_cfg->src_addr;
668		imxdmac->watermark_level = dmaengine_cfg->src_maxburst;
669		imxdmac->word_size = dmaengine_cfg->src_addr_width;
670	} else {
671		imxdmac->per_address = dmaengine_cfg->dst_addr;
672		imxdmac->watermark_level = dmaengine_cfg->dst_maxburst;
673		imxdmac->word_size = dmaengine_cfg->dst_addr_width;
674	}
675
676	switch (imxdmac->word_size) {
677	case DMA_SLAVE_BUSWIDTH_1_BYTE:
678		mode = IMX_DMA_MEMSIZE_8;
679		break;
680	case DMA_SLAVE_BUSWIDTH_2_BYTES:
681		mode = IMX_DMA_MEMSIZE_16;
682		break;
683	default:
684	case DMA_SLAVE_BUSWIDTH_4_BYTES:
685		mode = IMX_DMA_MEMSIZE_32;
686		break;
687	}
688
689	imxdmac->hw_chaining = 0;
690
691	imxdmac->ccr_from_device = (mode | IMX_DMA_TYPE_FIFO) |
692		((IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) << 2) |
693		CCR_REN;
694	imxdmac->ccr_to_device =
695		(IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) |
696		((mode | IMX_DMA_TYPE_FIFO) << 2) | CCR_REN;
697	imx_dmav1_writel(imxdma, imxdmac->dma_request,
698			 DMA_RSSR(imxdmac->channel));
699
700	/* Set burst length */
701	imx_dmav1_writel(imxdma, imxdmac->watermark_level *
702			 imxdmac->word_size, DMA_BLR(imxdmac->channel));
703
704	return 0;
705}
706
707static int imxdma_config(struct dma_chan *chan,
708			 struct dma_slave_config *dmaengine_cfg)
709{
710	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
711
712	memcpy(&imxdmac->config, dmaengine_cfg, sizeof(*dmaengine_cfg));
713
714	return 0;
715}
716
717static enum dma_status imxdma_tx_status(struct dma_chan *chan,
718					    dma_cookie_t cookie,
719					    struct dma_tx_state *txstate)
720{
721	return dma_cookie_status(chan, cookie, txstate);
722}
723
724static dma_cookie_t imxdma_tx_submit(struct dma_async_tx_descriptor *tx)
725{
726	struct imxdma_channel *imxdmac = to_imxdma_chan(tx->chan);
727	struct imxdma_engine *imxdma = imxdmac->imxdma;
728	dma_cookie_t cookie;
729	unsigned long flags;
730
731	spin_lock_irqsave(&imxdma->lock, flags);
732	list_move_tail(imxdmac->ld_free.next, &imxdmac->ld_queue);
733	cookie = dma_cookie_assign(tx);
734	spin_unlock_irqrestore(&imxdma->lock, flags);
735
736	return cookie;
737}
738
739static int imxdma_alloc_chan_resources(struct dma_chan *chan)
740{
741	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
742	struct imx_dma_data *data = chan->private;
743
744	if (data != NULL)
745		imxdmac->dma_request = data->dma_request;
746
747	while (imxdmac->descs_allocated < IMXDMA_MAX_CHAN_DESCRIPTORS) {
748		struct imxdma_desc *desc;
749
750		desc = kzalloc(sizeof(*desc), GFP_KERNEL);
751		if (!desc)
752			break;
753		dma_async_tx_descriptor_init(&desc->desc, chan);
754		desc->desc.tx_submit = imxdma_tx_submit;
755		/* txd.flags will be overwritten in prep funcs */
756		desc->desc.flags = DMA_CTRL_ACK;
757		desc->status = DMA_COMPLETE;
758
759		list_add_tail(&desc->node, &imxdmac->ld_free);
760		imxdmac->descs_allocated++;
761	}
762
763	if (!imxdmac->descs_allocated)
764		return -ENOMEM;
765
766	return imxdmac->descs_allocated;
767}
768
769static void imxdma_free_chan_resources(struct dma_chan *chan)
770{
771	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
772	struct imxdma_engine *imxdma = imxdmac->imxdma;
773	struct imxdma_desc *desc, *_desc;
774	unsigned long flags;
775
776	spin_lock_irqsave(&imxdma->lock, flags);
777
778	imxdma_disable_hw(imxdmac);
779	list_splice_tail_init(&imxdmac->ld_active, &imxdmac->ld_free);
780	list_splice_tail_init(&imxdmac->ld_queue, &imxdmac->ld_free);
781
782	spin_unlock_irqrestore(&imxdma->lock, flags);
783
784	list_for_each_entry_safe(desc, _desc, &imxdmac->ld_free, node) {
785		kfree(desc);
786		imxdmac->descs_allocated--;
787	}
788	INIT_LIST_HEAD(&imxdmac->ld_free);
789
790	kfree(imxdmac->sg_list);
791	imxdmac->sg_list = NULL;
792}
793
794static struct dma_async_tx_descriptor *imxdma_prep_slave_sg(
795		struct dma_chan *chan, struct scatterlist *sgl,
796		unsigned int sg_len, enum dma_transfer_direction direction,
797		unsigned long flags, void *context)
798{
799	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
800	struct scatterlist *sg;
801	int i, dma_length = 0;
802	struct imxdma_desc *desc;
803
804	if (list_empty(&imxdmac->ld_free) ||
805	    imxdma_chan_is_doing_cyclic(imxdmac))
806		return NULL;
807
808	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
809
810	for_each_sg(sgl, sg, sg_len, i) {
811		dma_length += sg_dma_len(sg);
812	}
813
814	imxdma_config_write(chan, &imxdmac->config, direction);
815
816	switch (imxdmac->word_size) {
817	case DMA_SLAVE_BUSWIDTH_4_BYTES:
818		if (sg_dma_len(sgl) & 3 || sgl->dma_address & 3)
819			return NULL;
820		break;
821	case DMA_SLAVE_BUSWIDTH_2_BYTES:
822		if (sg_dma_len(sgl) & 1 || sgl->dma_address & 1)
823			return NULL;
824		break;
825	case DMA_SLAVE_BUSWIDTH_1_BYTE:
826		break;
827	default:
828		return NULL;
829	}
830
831	desc->type = IMXDMA_DESC_SLAVE_SG;
832	desc->sg = sgl;
833	desc->sgcount = sg_len;
834	desc->len = dma_length;
835	desc->direction = direction;
836	if (direction == DMA_DEV_TO_MEM) {
837		desc->src = imxdmac->per_address;
838	} else {
839		desc->dest = imxdmac->per_address;
840	}
841	desc->desc.callback = NULL;
842	desc->desc.callback_param = NULL;
843
844	return &desc->desc;
845}
846
847static struct dma_async_tx_descriptor *imxdma_prep_dma_cyclic(
848		struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
849		size_t period_len, enum dma_transfer_direction direction,
850		unsigned long flags)
851{
852	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
853	struct imxdma_engine *imxdma = imxdmac->imxdma;
854	struct imxdma_desc *desc;
855	int i;
856	unsigned int periods = buf_len / period_len;
857
858	dev_dbg(imxdma->dev, "%s channel: %d buf_len=%zu period_len=%zu\n",
859			__func__, imxdmac->channel, buf_len, period_len);
860
861	if (list_empty(&imxdmac->ld_free) ||
862	    imxdma_chan_is_doing_cyclic(imxdmac))
863		return NULL;
864
865	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
866
867	kfree(imxdmac->sg_list);
868
869	imxdmac->sg_list = kcalloc(periods + 1,
870			sizeof(struct scatterlist), GFP_ATOMIC);
871	if (!imxdmac->sg_list)
872		return NULL;
873
874	sg_init_table(imxdmac->sg_list, periods);
875
876	for (i = 0; i < periods; i++) {
877		sg_assign_page(&imxdmac->sg_list[i], NULL);
878		imxdmac->sg_list[i].offset = 0;
879		imxdmac->sg_list[i].dma_address = dma_addr;
880		sg_dma_len(&imxdmac->sg_list[i]) = period_len;
881		dma_addr += period_len;
882	}
883
884	/* close the loop */
885	sg_chain(imxdmac->sg_list, periods + 1, imxdmac->sg_list);
886
887	desc->type = IMXDMA_DESC_CYCLIC;
888	desc->sg = imxdmac->sg_list;
889	desc->sgcount = periods;
890	desc->len = IMX_DMA_LENGTH_LOOP;
891	desc->direction = direction;
892	if (direction == DMA_DEV_TO_MEM) {
893		desc->src = imxdmac->per_address;
894	} else {
895		desc->dest = imxdmac->per_address;
896	}
897	desc->desc.callback = NULL;
898	desc->desc.callback_param = NULL;
899
900	imxdma_config_write(chan, &imxdmac->config, direction);
901
902	return &desc->desc;
903}
904
905static struct dma_async_tx_descriptor *imxdma_prep_dma_memcpy(
906	struct dma_chan *chan, dma_addr_t dest,
907	dma_addr_t src, size_t len, unsigned long flags)
908{
909	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
910	struct imxdma_engine *imxdma = imxdmac->imxdma;
911	struct imxdma_desc *desc;
912
913	dev_dbg(imxdma->dev, "%s channel: %d src=0x%llx dst=0x%llx len=%zu\n",
914		__func__, imxdmac->channel, (unsigned long long)src,
915		(unsigned long long)dest, len);
916
917	if (list_empty(&imxdmac->ld_free) ||
918	    imxdma_chan_is_doing_cyclic(imxdmac))
919		return NULL;
920
921	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
922
923	desc->type = IMXDMA_DESC_MEMCPY;
924	desc->src = src;
925	desc->dest = dest;
926	desc->len = len;
927	desc->direction = DMA_MEM_TO_MEM;
928	desc->config_port = IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR;
929	desc->config_mem = IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR;
930	desc->desc.callback = NULL;
931	desc->desc.callback_param = NULL;
932
933	return &desc->desc;
934}
935
936static struct dma_async_tx_descriptor *imxdma_prep_dma_interleaved(
937	struct dma_chan *chan, struct dma_interleaved_template *xt,
938	unsigned long flags)
939{
940	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
941	struct imxdma_engine *imxdma = imxdmac->imxdma;
942	struct imxdma_desc *desc;
943
944	dev_dbg(imxdma->dev, "%s channel: %d src_start=0x%llx dst_start=0x%llx\n"
945		"   src_sgl=%s dst_sgl=%s numf=%zu frame_size=%zu\n", __func__,
946		imxdmac->channel, (unsigned long long)xt->src_start,
947		(unsigned long long) xt->dst_start,
948		xt->src_sgl ? "true" : "false", xt->dst_sgl ? "true" : "false",
949		xt->numf, xt->frame_size);
950
951	if (list_empty(&imxdmac->ld_free) ||
952	    imxdma_chan_is_doing_cyclic(imxdmac))
953		return NULL;
954
955	if (xt->frame_size != 1 || xt->numf <= 0 || xt->dir != DMA_MEM_TO_MEM)
956		return NULL;
957
958	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
959
960	desc->type = IMXDMA_DESC_INTERLEAVED;
961	desc->src = xt->src_start;
962	desc->dest = xt->dst_start;
963	desc->x = xt->sgl[0].size;
964	desc->y = xt->numf;
965	desc->w = xt->sgl[0].icg + desc->x;
966	desc->len = desc->x * desc->y;
967	desc->direction = DMA_MEM_TO_MEM;
968	desc->config_port = IMX_DMA_MEMSIZE_32;
969	desc->config_mem = IMX_DMA_MEMSIZE_32;
970	if (xt->src_sgl)
971		desc->config_mem |= IMX_DMA_TYPE_2D;
972	if (xt->dst_sgl)
973		desc->config_port |= IMX_DMA_TYPE_2D;
974	desc->desc.callback = NULL;
975	desc->desc.callback_param = NULL;
976
977	return &desc->desc;
978}
979
980static void imxdma_issue_pending(struct dma_chan *chan)
981{
982	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
983	struct imxdma_engine *imxdma = imxdmac->imxdma;
984	struct imxdma_desc *desc;
985	unsigned long flags;
986
987	spin_lock_irqsave(&imxdma->lock, flags);
988	if (list_empty(&imxdmac->ld_active) &&
989	    !list_empty(&imxdmac->ld_queue)) {
990		desc = list_first_entry(&imxdmac->ld_queue,
991					struct imxdma_desc, node);
992
993		if (imxdma_xfer_desc(desc) < 0) {
994			dev_warn(imxdma->dev,
995				 "%s: channel: %d couldn't issue DMA xfer\n",
996				 __func__, imxdmac->channel);
997		} else {
998			list_move_tail(imxdmac->ld_queue.next,
999				       &imxdmac->ld_active);
1000		}
1001	}
1002	spin_unlock_irqrestore(&imxdma->lock, flags);
1003}
1004
1005static bool imxdma_filter_fn(struct dma_chan *chan, void *param)
1006{
1007	struct imxdma_filter_data *fdata = param;
1008	struct imxdma_channel *imxdma_chan = to_imxdma_chan(chan);
1009
1010	if (chan->device->dev != fdata->imxdma->dev)
1011		return false;
1012
1013	imxdma_chan->dma_request = fdata->request;
1014	chan->private = NULL;
1015
1016	return true;
1017}
1018
1019static struct dma_chan *imxdma_xlate(struct of_phandle_args *dma_spec,
1020						struct of_dma *ofdma)
1021{
1022	int count = dma_spec->args_count;
1023	struct imxdma_engine *imxdma = ofdma->of_dma_data;
1024	struct imxdma_filter_data fdata = {
1025		.imxdma = imxdma,
1026	};
1027
1028	if (count != 1)
1029		return NULL;
1030
1031	fdata.request = dma_spec->args[0];
1032
1033	return dma_request_channel(imxdma->dma_device.cap_mask,
1034					imxdma_filter_fn, &fdata);
1035}
1036
1037static int __init imxdma_probe(struct platform_device *pdev)
1038{
1039	struct imxdma_engine *imxdma;
1040	int ret, i;
1041	int irq, irq_err;
1042
1043	imxdma = devm_kzalloc(&pdev->dev, sizeof(*imxdma), GFP_KERNEL);
1044	if (!imxdma)
1045		return -ENOMEM;
1046
1047	imxdma->dev = &pdev->dev;
1048	imxdma->devtype = (uintptr_t)of_device_get_match_data(&pdev->dev);
1049
1050	imxdma->base = devm_platform_ioremap_resource(pdev, 0);
1051	if (IS_ERR(imxdma->base))
1052		return PTR_ERR(imxdma->base);
1053
1054	irq = platform_get_irq(pdev, 0);
1055	if (irq < 0)
1056		return irq;
1057
1058	imxdma->dma_ipg = devm_clk_get(&pdev->dev, "ipg");
1059	if (IS_ERR(imxdma->dma_ipg))
1060		return PTR_ERR(imxdma->dma_ipg);
1061
1062	imxdma->dma_ahb = devm_clk_get(&pdev->dev, "ahb");
1063	if (IS_ERR(imxdma->dma_ahb))
1064		return PTR_ERR(imxdma->dma_ahb);
1065
1066	ret = clk_prepare_enable(imxdma->dma_ipg);
1067	if (ret)
1068		return ret;
1069	ret = clk_prepare_enable(imxdma->dma_ahb);
1070	if (ret)
1071		goto disable_dma_ipg_clk;
1072
1073	/* reset DMA module */
1074	imx_dmav1_writel(imxdma, DCR_DRST, DMA_DCR);
1075
1076	if (is_imx1_dma(imxdma)) {
1077		ret = devm_request_irq(&pdev->dev, irq,
1078				       dma_irq_handler, 0, "DMA", imxdma);
1079		if (ret) {
1080			dev_warn(imxdma->dev, "Can't register IRQ for DMA\n");
1081			goto disable_dma_ahb_clk;
1082		}
1083		imxdma->irq = irq;
1084
1085		irq_err = platform_get_irq(pdev, 1);
1086		if (irq_err < 0) {
1087			ret = irq_err;
1088			goto disable_dma_ahb_clk;
1089		}
1090
1091		ret = devm_request_irq(&pdev->dev, irq_err,
1092				       imxdma_err_handler, 0, "DMA", imxdma);
1093		if (ret) {
1094			dev_warn(imxdma->dev, "Can't register ERRIRQ for DMA\n");
1095			goto disable_dma_ahb_clk;
1096		}
1097		imxdma->irq_err = irq_err;
1098	}
1099
1100	/* enable DMA module */
1101	imx_dmav1_writel(imxdma, DCR_DEN, DMA_DCR);
1102
1103	/* clear all interrupts */
1104	imx_dmav1_writel(imxdma, (1 << IMX_DMA_CHANNELS) - 1, DMA_DISR);
1105
1106	/* disable interrupts */
1107	imx_dmav1_writel(imxdma, (1 << IMX_DMA_CHANNELS) - 1, DMA_DIMR);
1108
1109	INIT_LIST_HEAD(&imxdma->dma_device.channels);
1110
1111	dma_cap_set(DMA_SLAVE, imxdma->dma_device.cap_mask);
1112	dma_cap_set(DMA_CYCLIC, imxdma->dma_device.cap_mask);
1113	dma_cap_set(DMA_MEMCPY, imxdma->dma_device.cap_mask);
1114	dma_cap_set(DMA_INTERLEAVE, imxdma->dma_device.cap_mask);
1115
1116	/* Initialize 2D global parameters */
1117	for (i = 0; i < IMX_DMA_2D_SLOTS; i++)
1118		imxdma->slots_2d[i].count = 0;
1119
1120	spin_lock_init(&imxdma->lock);
1121
1122	/* Initialize channel parameters */
1123	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
1124		struct imxdma_channel *imxdmac = &imxdma->channel[i];
1125
1126		if (!is_imx1_dma(imxdma)) {
1127			ret = devm_request_irq(&pdev->dev, irq + i,
1128					dma_irq_handler, 0, "DMA", imxdma);
1129			if (ret) {
1130				dev_warn(imxdma->dev, "Can't register IRQ %d "
1131					 "for DMA channel %d\n",
1132					 irq + i, i);
1133				goto disable_dma_ahb_clk;
1134			}
1135
1136			imxdmac->irq = irq + i;
1137			timer_setup(&imxdmac->watchdog, imxdma_watchdog, 0);
1138		}
1139
1140		imxdmac->imxdma = imxdma;
1141
1142		INIT_LIST_HEAD(&imxdmac->ld_queue);
1143		INIT_LIST_HEAD(&imxdmac->ld_free);
1144		INIT_LIST_HEAD(&imxdmac->ld_active);
1145
1146		tasklet_setup(&imxdmac->dma_tasklet, imxdma_tasklet);
1147		imxdmac->chan.device = &imxdma->dma_device;
1148		dma_cookie_init(&imxdmac->chan);
1149		imxdmac->channel = i;
1150
1151		/* Add the channel to the DMAC list */
1152		list_add_tail(&imxdmac->chan.device_node,
1153			      &imxdma->dma_device.channels);
1154	}
1155
1156	imxdma->dma_device.dev = &pdev->dev;
1157
1158	imxdma->dma_device.device_alloc_chan_resources = imxdma_alloc_chan_resources;
1159	imxdma->dma_device.device_free_chan_resources = imxdma_free_chan_resources;
1160	imxdma->dma_device.device_tx_status = imxdma_tx_status;
1161	imxdma->dma_device.device_prep_slave_sg = imxdma_prep_slave_sg;
1162	imxdma->dma_device.device_prep_dma_cyclic = imxdma_prep_dma_cyclic;
1163	imxdma->dma_device.device_prep_dma_memcpy = imxdma_prep_dma_memcpy;
1164	imxdma->dma_device.device_prep_interleaved_dma = imxdma_prep_dma_interleaved;
1165	imxdma->dma_device.device_config = imxdma_config;
1166	imxdma->dma_device.device_terminate_all = imxdma_terminate_all;
1167	imxdma->dma_device.device_issue_pending = imxdma_issue_pending;
1168
1169	platform_set_drvdata(pdev, imxdma);
1170
1171	imxdma->dma_device.copy_align = DMAENGINE_ALIGN_4_BYTES;
1172	dma_set_max_seg_size(imxdma->dma_device.dev, 0xffffff);
1173
1174	ret = dma_async_device_register(&imxdma->dma_device);
1175	if (ret) {
1176		dev_err(&pdev->dev, "unable to register\n");
1177		goto disable_dma_ahb_clk;
1178	}
1179
1180	if (pdev->dev.of_node) {
1181		ret = of_dma_controller_register(pdev->dev.of_node,
1182				imxdma_xlate, imxdma);
1183		if (ret) {
1184			dev_err(&pdev->dev, "unable to register of_dma_controller\n");
1185			goto err_of_dma_controller;
1186		}
1187	}
1188
1189	return 0;
1190
1191err_of_dma_controller:
1192	dma_async_device_unregister(&imxdma->dma_device);
1193disable_dma_ahb_clk:
1194	clk_disable_unprepare(imxdma->dma_ahb);
1195disable_dma_ipg_clk:
1196	clk_disable_unprepare(imxdma->dma_ipg);
1197	return ret;
1198}
1199
1200static void imxdma_free_irq(struct platform_device *pdev, struct imxdma_engine *imxdma)
1201{
1202	int i;
1203
1204	if (is_imx1_dma(imxdma)) {
1205		disable_irq(imxdma->irq);
1206		disable_irq(imxdma->irq_err);
1207	}
1208
1209	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
1210		struct imxdma_channel *imxdmac = &imxdma->channel[i];
1211
1212		if (!is_imx1_dma(imxdma))
1213			disable_irq(imxdmac->irq);
1214
1215		tasklet_kill(&imxdmac->dma_tasklet);
1216	}
1217}
1218
1219static void imxdma_remove(struct platform_device *pdev)
1220{
1221	struct imxdma_engine *imxdma = platform_get_drvdata(pdev);
1222
1223	imxdma_free_irq(pdev, imxdma);
1224
1225        dma_async_device_unregister(&imxdma->dma_device);
1226
1227	if (pdev->dev.of_node)
1228		of_dma_controller_free(pdev->dev.of_node);
1229
1230	clk_disable_unprepare(imxdma->dma_ipg);
1231	clk_disable_unprepare(imxdma->dma_ahb);
1232}
1233
1234static struct platform_driver imxdma_driver = {
1235	.driver		= {
1236		.name	= "imx-dma",
1237		.of_match_table = imx_dma_of_dev_id,
1238	},
1239	.remove_new	= imxdma_remove,
1240};
1241
1242static int __init imxdma_module_init(void)
1243{
1244	return platform_driver_probe(&imxdma_driver, imxdma_probe);
1245}
1246subsys_initcall(imxdma_module_init);
1247
1248MODULE_AUTHOR("Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>");
1249MODULE_DESCRIPTION("i.MX dma driver");
1250MODULE_LICENSE("GPL");
1251