xref: /openbmc/linux/drivers/dma/imx-dma.c (revision 161f4089)
1 /*
2  * drivers/dma/imx-dma.c
3  *
4  * This file contains a driver for the Freescale i.MX DMA engine
5  * found on i.MX1/21/27
6  *
7  * Copyright 2010 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
8  * Copyright 2012 Javier Martin, Vista Silicon <javier.martin@vista-silicon.com>
9  *
10  * The code contained herein is licensed under the GNU General Public
11  * License. You may obtain a copy of the GNU General Public License
12  * Version 2 or later at the following locations:
13  *
14  * http://www.opensource.org/licenses/gpl-license.html
15  * http://www.gnu.org/copyleft/gpl.html
16  */
17 #include <linux/err.h>
18 #include <linux/init.h>
19 #include <linux/types.h>
20 #include <linux/mm.h>
21 #include <linux/interrupt.h>
22 #include <linux/spinlock.h>
23 #include <linux/device.h>
24 #include <linux/dma-mapping.h>
25 #include <linux/slab.h>
26 #include <linux/platform_device.h>
27 #include <linux/clk.h>
28 #include <linux/dmaengine.h>
29 #include <linux/module.h>
30 #include <linux/of_device.h>
31 #include <linux/of_dma.h>
32 
33 #include <asm/irq.h>
34 #include <linux/platform_data/dma-imx.h>
35 
36 #include "dmaengine.h"
37 #define IMXDMA_MAX_CHAN_DESCRIPTORS	16
38 #define IMX_DMA_CHANNELS  16
39 
40 #define IMX_DMA_2D_SLOTS	2
41 #define IMX_DMA_2D_SLOT_A	0
42 #define IMX_DMA_2D_SLOT_B	1
43 
44 #define IMX_DMA_LENGTH_LOOP	((unsigned int)-1)
45 #define IMX_DMA_MEMSIZE_32	(0 << 4)
46 #define IMX_DMA_MEMSIZE_8	(1 << 4)
47 #define IMX_DMA_MEMSIZE_16	(2 << 4)
48 #define IMX_DMA_TYPE_LINEAR	(0 << 10)
49 #define IMX_DMA_TYPE_2D		(1 << 10)
50 #define IMX_DMA_TYPE_FIFO	(2 << 10)
51 
52 #define IMX_DMA_ERR_BURST     (1 << 0)
53 #define IMX_DMA_ERR_REQUEST   (1 << 1)
54 #define IMX_DMA_ERR_TRANSFER  (1 << 2)
55 #define IMX_DMA_ERR_BUFFER    (1 << 3)
56 #define IMX_DMA_ERR_TIMEOUT   (1 << 4)
57 
58 #define DMA_DCR     0x00		/* Control Register */
59 #define DMA_DISR    0x04		/* Interrupt status Register */
60 #define DMA_DIMR    0x08		/* Interrupt mask Register */
61 #define DMA_DBTOSR  0x0c		/* Burst timeout status Register */
62 #define DMA_DRTOSR  0x10		/* Request timeout Register */
63 #define DMA_DSESR   0x14		/* Transfer Error Status Register */
64 #define DMA_DBOSR   0x18		/* Buffer overflow status Register */
65 #define DMA_DBTOCR  0x1c		/* Burst timeout control Register */
66 #define DMA_WSRA    0x40		/* W-Size Register A */
67 #define DMA_XSRA    0x44		/* X-Size Register A */
68 #define DMA_YSRA    0x48		/* Y-Size Register A */
69 #define DMA_WSRB    0x4c		/* W-Size Register B */
70 #define DMA_XSRB    0x50		/* X-Size Register B */
71 #define DMA_YSRB    0x54		/* Y-Size Register B */
72 #define DMA_SAR(x)  (0x80 + ((x) << 6))	/* Source Address Registers */
73 #define DMA_DAR(x)  (0x84 + ((x) << 6))	/* Destination Address Registers */
74 #define DMA_CNTR(x) (0x88 + ((x) << 6))	/* Count Registers */
75 #define DMA_CCR(x)  (0x8c + ((x) << 6))	/* Control Registers */
76 #define DMA_RSSR(x) (0x90 + ((x) << 6))	/* Request source select Registers */
77 #define DMA_BLR(x)  (0x94 + ((x) << 6))	/* Burst length Registers */
78 #define DMA_RTOR(x) (0x98 + ((x) << 6))	/* Request timeout Registers */
79 #define DMA_BUCR(x) (0x98 + ((x) << 6))	/* Bus Utilization Registers */
80 #define DMA_CCNR(x) (0x9C + ((x) << 6))	/* Channel counter Registers */
81 
82 #define DCR_DRST           (1<<1)
83 #define DCR_DEN            (1<<0)
84 #define DBTOCR_EN          (1<<15)
85 #define DBTOCR_CNT(x)      ((x) & 0x7fff)
86 #define CNTR_CNT(x)        ((x) & 0xffffff)
87 #define CCR_ACRPT          (1<<14)
88 #define CCR_DMOD_LINEAR    (0x0 << 12)
89 #define CCR_DMOD_2D        (0x1 << 12)
90 #define CCR_DMOD_FIFO      (0x2 << 12)
91 #define CCR_DMOD_EOBFIFO   (0x3 << 12)
92 #define CCR_SMOD_LINEAR    (0x0 << 10)
93 #define CCR_SMOD_2D        (0x1 << 10)
94 #define CCR_SMOD_FIFO      (0x2 << 10)
95 #define CCR_SMOD_EOBFIFO   (0x3 << 10)
96 #define CCR_MDIR_DEC       (1<<9)
97 #define CCR_MSEL_B         (1<<8)
98 #define CCR_DSIZ_32        (0x0 << 6)
99 #define CCR_DSIZ_8         (0x1 << 6)
100 #define CCR_DSIZ_16        (0x2 << 6)
101 #define CCR_SSIZ_32        (0x0 << 4)
102 #define CCR_SSIZ_8         (0x1 << 4)
103 #define CCR_SSIZ_16        (0x2 << 4)
104 #define CCR_REN            (1<<3)
105 #define CCR_RPT            (1<<2)
106 #define CCR_FRC            (1<<1)
107 #define CCR_CEN            (1<<0)
108 #define RTOR_EN            (1<<15)
109 #define RTOR_CLK           (1<<14)
110 #define RTOR_PSC           (1<<13)
111 
112 enum  imxdma_prep_type {
113 	IMXDMA_DESC_MEMCPY,
114 	IMXDMA_DESC_INTERLEAVED,
115 	IMXDMA_DESC_SLAVE_SG,
116 	IMXDMA_DESC_CYCLIC,
117 };
118 
119 struct imx_dma_2d_config {
120 	u16		xsr;
121 	u16		ysr;
122 	u16		wsr;
123 	int		count;
124 };
125 
126 struct imxdma_desc {
127 	struct list_head		node;
128 	struct dma_async_tx_descriptor	desc;
129 	enum dma_status			status;
130 	dma_addr_t			src;
131 	dma_addr_t			dest;
132 	size_t				len;
133 	enum dma_transfer_direction	direction;
134 	enum imxdma_prep_type		type;
135 	/* For memcpy and interleaved */
136 	unsigned int			config_port;
137 	unsigned int			config_mem;
138 	/* For interleaved transfers */
139 	unsigned int			x;
140 	unsigned int			y;
141 	unsigned int			w;
142 	/* For slave sg and cyclic */
143 	struct scatterlist		*sg;
144 	unsigned int			sgcount;
145 };
146 
147 struct imxdma_channel {
148 	int				hw_chaining;
149 	struct timer_list		watchdog;
150 	struct imxdma_engine		*imxdma;
151 	unsigned int			channel;
152 
153 	struct tasklet_struct		dma_tasklet;
154 	struct list_head		ld_free;
155 	struct list_head		ld_queue;
156 	struct list_head		ld_active;
157 	int				descs_allocated;
158 	enum dma_slave_buswidth		word_size;
159 	dma_addr_t			per_address;
160 	u32				watermark_level;
161 	struct dma_chan			chan;
162 	struct dma_async_tx_descriptor	desc;
163 	enum dma_status			status;
164 	int				dma_request;
165 	struct scatterlist		*sg_list;
166 	u32				ccr_from_device;
167 	u32				ccr_to_device;
168 	bool				enabled_2d;
169 	int				slot_2d;
170 };
171 
172 enum imx_dma_type {
173 	IMX1_DMA,
174 	IMX21_DMA,
175 	IMX27_DMA,
176 };
177 
178 struct imxdma_engine {
179 	struct device			*dev;
180 	struct device_dma_parameters	dma_parms;
181 	struct dma_device		dma_device;
182 	void __iomem			*base;
183 	struct clk			*dma_ahb;
184 	struct clk			*dma_ipg;
185 	spinlock_t			lock;
186 	struct imx_dma_2d_config	slots_2d[IMX_DMA_2D_SLOTS];
187 	struct imxdma_channel		channel[IMX_DMA_CHANNELS];
188 	enum imx_dma_type		devtype;
189 };
190 
191 struct imxdma_filter_data {
192 	struct imxdma_engine	*imxdma;
193 	int			 request;
194 };
195 
196 static struct platform_device_id imx_dma_devtype[] = {
197 	{
198 		.name = "imx1-dma",
199 		.driver_data = IMX1_DMA,
200 	}, {
201 		.name = "imx21-dma",
202 		.driver_data = IMX21_DMA,
203 	}, {
204 		.name = "imx27-dma",
205 		.driver_data = IMX27_DMA,
206 	}, {
207 		/* sentinel */
208 	}
209 };
210 MODULE_DEVICE_TABLE(platform, imx_dma_devtype);
211 
212 static const struct of_device_id imx_dma_of_dev_id[] = {
213 	{
214 		.compatible = "fsl,imx1-dma",
215 		.data = &imx_dma_devtype[IMX1_DMA],
216 	}, {
217 		.compatible = "fsl,imx21-dma",
218 		.data = &imx_dma_devtype[IMX21_DMA],
219 	}, {
220 		.compatible = "fsl,imx27-dma",
221 		.data = &imx_dma_devtype[IMX27_DMA],
222 	}, {
223 		/* sentinel */
224 	}
225 };
226 MODULE_DEVICE_TABLE(of, imx_dma_of_dev_id);
227 
228 static inline int is_imx1_dma(struct imxdma_engine *imxdma)
229 {
230 	return imxdma->devtype == IMX1_DMA;
231 }
232 
233 static inline int is_imx21_dma(struct imxdma_engine *imxdma)
234 {
235 	return imxdma->devtype == IMX21_DMA;
236 }
237 
238 static inline int is_imx27_dma(struct imxdma_engine *imxdma)
239 {
240 	return imxdma->devtype == IMX27_DMA;
241 }
242 
243 static struct imxdma_channel *to_imxdma_chan(struct dma_chan *chan)
244 {
245 	return container_of(chan, struct imxdma_channel, chan);
246 }
247 
248 static inline bool imxdma_chan_is_doing_cyclic(struct imxdma_channel *imxdmac)
249 {
250 	struct imxdma_desc *desc;
251 
252 	if (!list_empty(&imxdmac->ld_active)) {
253 		desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc,
254 					node);
255 		if (desc->type == IMXDMA_DESC_CYCLIC)
256 			return true;
257 	}
258 	return false;
259 }
260 
261 
262 
263 static void imx_dmav1_writel(struct imxdma_engine *imxdma, unsigned val,
264 			     unsigned offset)
265 {
266 	__raw_writel(val, imxdma->base + offset);
267 }
268 
269 static unsigned imx_dmav1_readl(struct imxdma_engine *imxdma, unsigned offset)
270 {
271 	return __raw_readl(imxdma->base + offset);
272 }
273 
274 static int imxdma_hw_chain(struct imxdma_channel *imxdmac)
275 {
276 	struct imxdma_engine *imxdma = imxdmac->imxdma;
277 
278 	if (is_imx27_dma(imxdma))
279 		return imxdmac->hw_chaining;
280 	else
281 		return 0;
282 }
283 
284 /*
285  * imxdma_sg_next - prepare next chunk for scatter-gather DMA emulation
286  */
287 static inline int imxdma_sg_next(struct imxdma_desc *d)
288 {
289 	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
290 	struct imxdma_engine *imxdma = imxdmac->imxdma;
291 	struct scatterlist *sg = d->sg;
292 	unsigned long now;
293 
294 	now = min(d->len, sg_dma_len(sg));
295 	if (d->len != IMX_DMA_LENGTH_LOOP)
296 		d->len -= now;
297 
298 	if (d->direction == DMA_DEV_TO_MEM)
299 		imx_dmav1_writel(imxdma, sg->dma_address,
300 				 DMA_DAR(imxdmac->channel));
301 	else
302 		imx_dmav1_writel(imxdma, sg->dma_address,
303 				 DMA_SAR(imxdmac->channel));
304 
305 	imx_dmav1_writel(imxdma, now, DMA_CNTR(imxdmac->channel));
306 
307 	dev_dbg(imxdma->dev, " %s channel: %d dst 0x%08x, src 0x%08x, "
308 		"size 0x%08x\n", __func__, imxdmac->channel,
309 		 imx_dmav1_readl(imxdma, DMA_DAR(imxdmac->channel)),
310 		 imx_dmav1_readl(imxdma, DMA_SAR(imxdmac->channel)),
311 		 imx_dmav1_readl(imxdma, DMA_CNTR(imxdmac->channel)));
312 
313 	return now;
314 }
315 
316 static void imxdma_enable_hw(struct imxdma_desc *d)
317 {
318 	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
319 	struct imxdma_engine *imxdma = imxdmac->imxdma;
320 	int channel = imxdmac->channel;
321 	unsigned long flags;
322 
323 	dev_dbg(imxdma->dev, "%s channel %d\n", __func__, channel);
324 
325 	local_irq_save(flags);
326 
327 	imx_dmav1_writel(imxdma, 1 << channel, DMA_DISR);
328 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_DIMR) &
329 			 ~(1 << channel), DMA_DIMR);
330 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_CCR(channel)) |
331 			 CCR_CEN | CCR_ACRPT, DMA_CCR(channel));
332 
333 	if (!is_imx1_dma(imxdma) &&
334 			d->sg && imxdma_hw_chain(imxdmac)) {
335 		d->sg = sg_next(d->sg);
336 		if (d->sg) {
337 			u32 tmp;
338 			imxdma_sg_next(d);
339 			tmp = imx_dmav1_readl(imxdma, DMA_CCR(channel));
340 			imx_dmav1_writel(imxdma, tmp | CCR_RPT | CCR_ACRPT,
341 					 DMA_CCR(channel));
342 		}
343 	}
344 
345 	local_irq_restore(flags);
346 }
347 
348 static void imxdma_disable_hw(struct imxdma_channel *imxdmac)
349 {
350 	struct imxdma_engine *imxdma = imxdmac->imxdma;
351 	int channel = imxdmac->channel;
352 	unsigned long flags;
353 
354 	dev_dbg(imxdma->dev, "%s channel %d\n", __func__, channel);
355 
356 	if (imxdma_hw_chain(imxdmac))
357 		del_timer(&imxdmac->watchdog);
358 
359 	local_irq_save(flags);
360 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_DIMR) |
361 			 (1 << channel), DMA_DIMR);
362 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_CCR(channel)) &
363 			 ~CCR_CEN, DMA_CCR(channel));
364 	imx_dmav1_writel(imxdma, 1 << channel, DMA_DISR);
365 	local_irq_restore(flags);
366 }
367 
368 static void imxdma_watchdog(unsigned long data)
369 {
370 	struct imxdma_channel *imxdmac = (struct imxdma_channel *)data;
371 	struct imxdma_engine *imxdma = imxdmac->imxdma;
372 	int channel = imxdmac->channel;
373 
374 	imx_dmav1_writel(imxdma, 0, DMA_CCR(channel));
375 
376 	/* Tasklet watchdog error handler */
377 	tasklet_schedule(&imxdmac->dma_tasklet);
378 	dev_dbg(imxdma->dev, "channel %d: watchdog timeout!\n",
379 		imxdmac->channel);
380 }
381 
382 static irqreturn_t imxdma_err_handler(int irq, void *dev_id)
383 {
384 	struct imxdma_engine *imxdma = dev_id;
385 	unsigned int err_mask;
386 	int i, disr;
387 	int errcode;
388 
389 	disr = imx_dmav1_readl(imxdma, DMA_DISR);
390 
391 	err_mask = imx_dmav1_readl(imxdma, DMA_DBTOSR) |
392 		   imx_dmav1_readl(imxdma, DMA_DRTOSR) |
393 		   imx_dmav1_readl(imxdma, DMA_DSESR)  |
394 		   imx_dmav1_readl(imxdma, DMA_DBOSR);
395 
396 	if (!err_mask)
397 		return IRQ_HANDLED;
398 
399 	imx_dmav1_writel(imxdma, disr & err_mask, DMA_DISR);
400 
401 	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
402 		if (!(err_mask & (1 << i)))
403 			continue;
404 		errcode = 0;
405 
406 		if (imx_dmav1_readl(imxdma, DMA_DBTOSR) & (1 << i)) {
407 			imx_dmav1_writel(imxdma, 1 << i, DMA_DBTOSR);
408 			errcode |= IMX_DMA_ERR_BURST;
409 		}
410 		if (imx_dmav1_readl(imxdma, DMA_DRTOSR) & (1 << i)) {
411 			imx_dmav1_writel(imxdma, 1 << i, DMA_DRTOSR);
412 			errcode |= IMX_DMA_ERR_REQUEST;
413 		}
414 		if (imx_dmav1_readl(imxdma, DMA_DSESR) & (1 << i)) {
415 			imx_dmav1_writel(imxdma, 1 << i, DMA_DSESR);
416 			errcode |= IMX_DMA_ERR_TRANSFER;
417 		}
418 		if (imx_dmav1_readl(imxdma, DMA_DBOSR) & (1 << i)) {
419 			imx_dmav1_writel(imxdma, 1 << i, DMA_DBOSR);
420 			errcode |= IMX_DMA_ERR_BUFFER;
421 		}
422 		/* Tasklet error handler */
423 		tasklet_schedule(&imxdma->channel[i].dma_tasklet);
424 
425 		printk(KERN_WARNING
426 		       "DMA timeout on channel %d -%s%s%s%s\n", i,
427 		       errcode & IMX_DMA_ERR_BURST ?    " burst" : "",
428 		       errcode & IMX_DMA_ERR_REQUEST ?  " request" : "",
429 		       errcode & IMX_DMA_ERR_TRANSFER ? " transfer" : "",
430 		       errcode & IMX_DMA_ERR_BUFFER ?   " buffer" : "");
431 	}
432 	return IRQ_HANDLED;
433 }
434 
435 static void dma_irq_handle_channel(struct imxdma_channel *imxdmac)
436 {
437 	struct imxdma_engine *imxdma = imxdmac->imxdma;
438 	int chno = imxdmac->channel;
439 	struct imxdma_desc *desc;
440 	unsigned long flags;
441 
442 	spin_lock_irqsave(&imxdma->lock, flags);
443 	if (list_empty(&imxdmac->ld_active)) {
444 		spin_unlock_irqrestore(&imxdma->lock, flags);
445 		goto out;
446 	}
447 
448 	desc = list_first_entry(&imxdmac->ld_active,
449 				struct imxdma_desc,
450 				node);
451 	spin_unlock_irqrestore(&imxdma->lock, flags);
452 
453 	if (desc->sg) {
454 		u32 tmp;
455 		desc->sg = sg_next(desc->sg);
456 
457 		if (desc->sg) {
458 			imxdma_sg_next(desc);
459 
460 			tmp = imx_dmav1_readl(imxdma, DMA_CCR(chno));
461 
462 			if (imxdma_hw_chain(imxdmac)) {
463 				/* FIXME: The timeout should probably be
464 				 * configurable
465 				 */
466 				mod_timer(&imxdmac->watchdog,
467 					jiffies + msecs_to_jiffies(500));
468 
469 				tmp |= CCR_CEN | CCR_RPT | CCR_ACRPT;
470 				imx_dmav1_writel(imxdma, tmp, DMA_CCR(chno));
471 			} else {
472 				imx_dmav1_writel(imxdma, tmp & ~CCR_CEN,
473 						 DMA_CCR(chno));
474 				tmp |= CCR_CEN;
475 			}
476 
477 			imx_dmav1_writel(imxdma, tmp, DMA_CCR(chno));
478 
479 			if (imxdma_chan_is_doing_cyclic(imxdmac))
480 				/* Tasklet progression */
481 				tasklet_schedule(&imxdmac->dma_tasklet);
482 
483 			return;
484 		}
485 
486 		if (imxdma_hw_chain(imxdmac)) {
487 			del_timer(&imxdmac->watchdog);
488 			return;
489 		}
490 	}
491 
492 out:
493 	imx_dmav1_writel(imxdma, 0, DMA_CCR(chno));
494 	/* Tasklet irq */
495 	tasklet_schedule(&imxdmac->dma_tasklet);
496 }
497 
498 static irqreturn_t dma_irq_handler(int irq, void *dev_id)
499 {
500 	struct imxdma_engine *imxdma = dev_id;
501 	int i, disr;
502 
503 	if (!is_imx1_dma(imxdma))
504 		imxdma_err_handler(irq, dev_id);
505 
506 	disr = imx_dmav1_readl(imxdma, DMA_DISR);
507 
508 	dev_dbg(imxdma->dev, "%s called, disr=0x%08x\n", __func__, disr);
509 
510 	imx_dmav1_writel(imxdma, disr, DMA_DISR);
511 	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
512 		if (disr & (1 << i))
513 			dma_irq_handle_channel(&imxdma->channel[i]);
514 	}
515 
516 	return IRQ_HANDLED;
517 }
518 
519 static int imxdma_xfer_desc(struct imxdma_desc *d)
520 {
521 	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
522 	struct imxdma_engine *imxdma = imxdmac->imxdma;
523 	int slot = -1;
524 	int i;
525 
526 	/* Configure and enable */
527 	switch (d->type) {
528 	case IMXDMA_DESC_INTERLEAVED:
529 		/* Try to get a free 2D slot */
530 		for (i = 0; i < IMX_DMA_2D_SLOTS; i++) {
531 			if ((imxdma->slots_2d[i].count > 0) &&
532 			((imxdma->slots_2d[i].xsr != d->x) ||
533 			(imxdma->slots_2d[i].ysr != d->y) ||
534 			(imxdma->slots_2d[i].wsr != d->w)))
535 				continue;
536 			slot = i;
537 			break;
538 		}
539 		if (slot < 0)
540 			return -EBUSY;
541 
542 		imxdma->slots_2d[slot].xsr = d->x;
543 		imxdma->slots_2d[slot].ysr = d->y;
544 		imxdma->slots_2d[slot].wsr = d->w;
545 		imxdma->slots_2d[slot].count++;
546 
547 		imxdmac->slot_2d = slot;
548 		imxdmac->enabled_2d = true;
549 
550 		if (slot == IMX_DMA_2D_SLOT_A) {
551 			d->config_mem &= ~CCR_MSEL_B;
552 			d->config_port &= ~CCR_MSEL_B;
553 			imx_dmav1_writel(imxdma, d->x, DMA_XSRA);
554 			imx_dmav1_writel(imxdma, d->y, DMA_YSRA);
555 			imx_dmav1_writel(imxdma, d->w, DMA_WSRA);
556 		} else {
557 			d->config_mem |= CCR_MSEL_B;
558 			d->config_port |= CCR_MSEL_B;
559 			imx_dmav1_writel(imxdma, d->x, DMA_XSRB);
560 			imx_dmav1_writel(imxdma, d->y, DMA_YSRB);
561 			imx_dmav1_writel(imxdma, d->w, DMA_WSRB);
562 		}
563 		/*
564 		 * We fall-through here intentionally, since a 2D transfer is
565 		 * similar to MEMCPY just adding the 2D slot configuration.
566 		 */
567 	case IMXDMA_DESC_MEMCPY:
568 		imx_dmav1_writel(imxdma, d->src, DMA_SAR(imxdmac->channel));
569 		imx_dmav1_writel(imxdma, d->dest, DMA_DAR(imxdmac->channel));
570 		imx_dmav1_writel(imxdma, d->config_mem | (d->config_port << 2),
571 			 DMA_CCR(imxdmac->channel));
572 
573 		imx_dmav1_writel(imxdma, d->len, DMA_CNTR(imxdmac->channel));
574 
575 		dev_dbg(imxdma->dev, "%s channel: %d dest=0x%08x src=0x%08x "
576 			"dma_length=%d\n", __func__, imxdmac->channel,
577 			d->dest, d->src, d->len);
578 
579 		break;
580 	/* Cyclic transfer is the same as slave_sg with special sg configuration. */
581 	case IMXDMA_DESC_CYCLIC:
582 	case IMXDMA_DESC_SLAVE_SG:
583 		if (d->direction == DMA_DEV_TO_MEM) {
584 			imx_dmav1_writel(imxdma, imxdmac->per_address,
585 					 DMA_SAR(imxdmac->channel));
586 			imx_dmav1_writel(imxdma, imxdmac->ccr_from_device,
587 					 DMA_CCR(imxdmac->channel));
588 
589 			dev_dbg(imxdma->dev, "%s channel: %d sg=%p sgcount=%d "
590 				"total length=%d dev_addr=0x%08x (dev2mem)\n",
591 				__func__, imxdmac->channel, d->sg, d->sgcount,
592 				d->len, imxdmac->per_address);
593 		} else if (d->direction == DMA_MEM_TO_DEV) {
594 			imx_dmav1_writel(imxdma, imxdmac->per_address,
595 					 DMA_DAR(imxdmac->channel));
596 			imx_dmav1_writel(imxdma, imxdmac->ccr_to_device,
597 					 DMA_CCR(imxdmac->channel));
598 
599 			dev_dbg(imxdma->dev, "%s channel: %d sg=%p sgcount=%d "
600 				"total length=%d dev_addr=0x%08x (mem2dev)\n",
601 				__func__, imxdmac->channel, d->sg, d->sgcount,
602 				d->len, imxdmac->per_address);
603 		} else {
604 			dev_err(imxdma->dev, "%s channel: %d bad dma mode\n",
605 				__func__, imxdmac->channel);
606 			return -EINVAL;
607 		}
608 
609 		imxdma_sg_next(d);
610 
611 		break;
612 	default:
613 		return -EINVAL;
614 	}
615 	imxdma_enable_hw(d);
616 	return 0;
617 }
618 
619 static void imxdma_tasklet(unsigned long data)
620 {
621 	struct imxdma_channel *imxdmac = (void *)data;
622 	struct imxdma_engine *imxdma = imxdmac->imxdma;
623 	struct imxdma_desc *desc;
624 	unsigned long flags;
625 
626 	spin_lock_irqsave(&imxdma->lock, flags);
627 
628 	if (list_empty(&imxdmac->ld_active)) {
629 		/* Someone might have called terminate all */
630 		spin_unlock_irqrestore(&imxdma->lock, flags);
631 		return;
632 	}
633 	desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc, node);
634 
635 	/* If we are dealing with a cyclic descriptor, keep it on ld_active
636 	 * and dont mark the descriptor as complete.
637 	 * Only in non-cyclic cases it would be marked as complete
638 	 */
639 	if (imxdma_chan_is_doing_cyclic(imxdmac))
640 		goto out;
641 	else
642 		dma_cookie_complete(&desc->desc);
643 
644 	/* Free 2D slot if it was an interleaved transfer */
645 	if (imxdmac->enabled_2d) {
646 		imxdma->slots_2d[imxdmac->slot_2d].count--;
647 		imxdmac->enabled_2d = false;
648 	}
649 
650 	list_move_tail(imxdmac->ld_active.next, &imxdmac->ld_free);
651 
652 	if (!list_empty(&imxdmac->ld_queue)) {
653 		desc = list_first_entry(&imxdmac->ld_queue, struct imxdma_desc,
654 					node);
655 		list_move_tail(imxdmac->ld_queue.next, &imxdmac->ld_active);
656 		if (imxdma_xfer_desc(desc) < 0)
657 			dev_warn(imxdma->dev, "%s: channel: %d couldn't xfer desc\n",
658 				 __func__, imxdmac->channel);
659 	}
660 out:
661 	spin_unlock_irqrestore(&imxdma->lock, flags);
662 
663 	if (desc->desc.callback)
664 		desc->desc.callback(desc->desc.callback_param);
665 
666 }
667 
668 static int imxdma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
669 		unsigned long arg)
670 {
671 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
672 	struct dma_slave_config *dmaengine_cfg = (void *)arg;
673 	struct imxdma_engine *imxdma = imxdmac->imxdma;
674 	unsigned long flags;
675 	unsigned int mode = 0;
676 
677 	switch (cmd) {
678 	case DMA_TERMINATE_ALL:
679 		imxdma_disable_hw(imxdmac);
680 
681 		spin_lock_irqsave(&imxdma->lock, flags);
682 		list_splice_tail_init(&imxdmac->ld_active, &imxdmac->ld_free);
683 		list_splice_tail_init(&imxdmac->ld_queue, &imxdmac->ld_free);
684 		spin_unlock_irqrestore(&imxdma->lock, flags);
685 		return 0;
686 	case DMA_SLAVE_CONFIG:
687 		if (dmaengine_cfg->direction == DMA_DEV_TO_MEM) {
688 			imxdmac->per_address = dmaengine_cfg->src_addr;
689 			imxdmac->watermark_level = dmaengine_cfg->src_maxburst;
690 			imxdmac->word_size = dmaengine_cfg->src_addr_width;
691 		} else {
692 			imxdmac->per_address = dmaengine_cfg->dst_addr;
693 			imxdmac->watermark_level = dmaengine_cfg->dst_maxburst;
694 			imxdmac->word_size = dmaengine_cfg->dst_addr_width;
695 		}
696 
697 		switch (imxdmac->word_size) {
698 		case DMA_SLAVE_BUSWIDTH_1_BYTE:
699 			mode = IMX_DMA_MEMSIZE_8;
700 			break;
701 		case DMA_SLAVE_BUSWIDTH_2_BYTES:
702 			mode = IMX_DMA_MEMSIZE_16;
703 			break;
704 		default:
705 		case DMA_SLAVE_BUSWIDTH_4_BYTES:
706 			mode = IMX_DMA_MEMSIZE_32;
707 			break;
708 		}
709 
710 		imxdmac->hw_chaining = 0;
711 
712 		imxdmac->ccr_from_device = (mode | IMX_DMA_TYPE_FIFO) |
713 			((IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) << 2) |
714 			CCR_REN;
715 		imxdmac->ccr_to_device =
716 			(IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) |
717 			((mode | IMX_DMA_TYPE_FIFO) << 2) | CCR_REN;
718 		imx_dmav1_writel(imxdma, imxdmac->dma_request,
719 				 DMA_RSSR(imxdmac->channel));
720 
721 		/* Set burst length */
722 		imx_dmav1_writel(imxdma, imxdmac->watermark_level *
723 				imxdmac->word_size, DMA_BLR(imxdmac->channel));
724 
725 		return 0;
726 	default:
727 		return -ENOSYS;
728 	}
729 
730 	return -EINVAL;
731 }
732 
733 static enum dma_status imxdma_tx_status(struct dma_chan *chan,
734 					    dma_cookie_t cookie,
735 					    struct dma_tx_state *txstate)
736 {
737 	return dma_cookie_status(chan, cookie, txstate);
738 }
739 
740 static dma_cookie_t imxdma_tx_submit(struct dma_async_tx_descriptor *tx)
741 {
742 	struct imxdma_channel *imxdmac = to_imxdma_chan(tx->chan);
743 	struct imxdma_engine *imxdma = imxdmac->imxdma;
744 	dma_cookie_t cookie;
745 	unsigned long flags;
746 
747 	spin_lock_irqsave(&imxdma->lock, flags);
748 	list_move_tail(imxdmac->ld_free.next, &imxdmac->ld_queue);
749 	cookie = dma_cookie_assign(tx);
750 	spin_unlock_irqrestore(&imxdma->lock, flags);
751 
752 	return cookie;
753 }
754 
755 static int imxdma_alloc_chan_resources(struct dma_chan *chan)
756 {
757 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
758 	struct imx_dma_data *data = chan->private;
759 
760 	if (data != NULL)
761 		imxdmac->dma_request = data->dma_request;
762 
763 	while (imxdmac->descs_allocated < IMXDMA_MAX_CHAN_DESCRIPTORS) {
764 		struct imxdma_desc *desc;
765 
766 		desc = kzalloc(sizeof(*desc), GFP_KERNEL);
767 		if (!desc)
768 			break;
769 		__memzero(&desc->desc, sizeof(struct dma_async_tx_descriptor));
770 		dma_async_tx_descriptor_init(&desc->desc, chan);
771 		desc->desc.tx_submit = imxdma_tx_submit;
772 		/* txd.flags will be overwritten in prep funcs */
773 		desc->desc.flags = DMA_CTRL_ACK;
774 		desc->status = DMA_SUCCESS;
775 
776 		list_add_tail(&desc->node, &imxdmac->ld_free);
777 		imxdmac->descs_allocated++;
778 	}
779 
780 	if (!imxdmac->descs_allocated)
781 		return -ENOMEM;
782 
783 	return imxdmac->descs_allocated;
784 }
785 
786 static void imxdma_free_chan_resources(struct dma_chan *chan)
787 {
788 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
789 	struct imxdma_engine *imxdma = imxdmac->imxdma;
790 	struct imxdma_desc *desc, *_desc;
791 	unsigned long flags;
792 
793 	spin_lock_irqsave(&imxdma->lock, flags);
794 
795 	imxdma_disable_hw(imxdmac);
796 	list_splice_tail_init(&imxdmac->ld_active, &imxdmac->ld_free);
797 	list_splice_tail_init(&imxdmac->ld_queue, &imxdmac->ld_free);
798 
799 	spin_unlock_irqrestore(&imxdma->lock, flags);
800 
801 	list_for_each_entry_safe(desc, _desc, &imxdmac->ld_free, node) {
802 		kfree(desc);
803 		imxdmac->descs_allocated--;
804 	}
805 	INIT_LIST_HEAD(&imxdmac->ld_free);
806 
807 	kfree(imxdmac->sg_list);
808 	imxdmac->sg_list = NULL;
809 }
810 
811 static struct dma_async_tx_descriptor *imxdma_prep_slave_sg(
812 		struct dma_chan *chan, struct scatterlist *sgl,
813 		unsigned int sg_len, enum dma_transfer_direction direction,
814 		unsigned long flags, void *context)
815 {
816 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
817 	struct scatterlist *sg;
818 	int i, dma_length = 0;
819 	struct imxdma_desc *desc;
820 
821 	if (list_empty(&imxdmac->ld_free) ||
822 	    imxdma_chan_is_doing_cyclic(imxdmac))
823 		return NULL;
824 
825 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
826 
827 	for_each_sg(sgl, sg, sg_len, i) {
828 		dma_length += sg_dma_len(sg);
829 	}
830 
831 	switch (imxdmac->word_size) {
832 	case DMA_SLAVE_BUSWIDTH_4_BYTES:
833 		if (sg_dma_len(sgl) & 3 || sgl->dma_address & 3)
834 			return NULL;
835 		break;
836 	case DMA_SLAVE_BUSWIDTH_2_BYTES:
837 		if (sg_dma_len(sgl) & 1 || sgl->dma_address & 1)
838 			return NULL;
839 		break;
840 	case DMA_SLAVE_BUSWIDTH_1_BYTE:
841 		break;
842 	default:
843 		return NULL;
844 	}
845 
846 	desc->type = IMXDMA_DESC_SLAVE_SG;
847 	desc->sg = sgl;
848 	desc->sgcount = sg_len;
849 	desc->len = dma_length;
850 	desc->direction = direction;
851 	if (direction == DMA_DEV_TO_MEM) {
852 		desc->src = imxdmac->per_address;
853 	} else {
854 		desc->dest = imxdmac->per_address;
855 	}
856 	desc->desc.callback = NULL;
857 	desc->desc.callback_param = NULL;
858 
859 	return &desc->desc;
860 }
861 
862 static struct dma_async_tx_descriptor *imxdma_prep_dma_cyclic(
863 		struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
864 		size_t period_len, enum dma_transfer_direction direction,
865 		unsigned long flags, void *context)
866 {
867 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
868 	struct imxdma_engine *imxdma = imxdmac->imxdma;
869 	struct imxdma_desc *desc;
870 	int i;
871 	unsigned int periods = buf_len / period_len;
872 
873 	dev_dbg(imxdma->dev, "%s channel: %d buf_len=%d period_len=%d\n",
874 			__func__, imxdmac->channel, buf_len, period_len);
875 
876 	if (list_empty(&imxdmac->ld_free) ||
877 	    imxdma_chan_is_doing_cyclic(imxdmac))
878 		return NULL;
879 
880 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
881 
882 	kfree(imxdmac->sg_list);
883 
884 	imxdmac->sg_list = kcalloc(periods + 1,
885 			sizeof(struct scatterlist), GFP_ATOMIC);
886 	if (!imxdmac->sg_list)
887 		return NULL;
888 
889 	sg_init_table(imxdmac->sg_list, periods);
890 
891 	for (i = 0; i < periods; i++) {
892 		imxdmac->sg_list[i].page_link = 0;
893 		imxdmac->sg_list[i].offset = 0;
894 		imxdmac->sg_list[i].dma_address = dma_addr;
895 		sg_dma_len(&imxdmac->sg_list[i]) = period_len;
896 		dma_addr += period_len;
897 	}
898 
899 	/* close the loop */
900 	imxdmac->sg_list[periods].offset = 0;
901 	sg_dma_len(&imxdmac->sg_list[periods]) = 0;
902 	imxdmac->sg_list[periods].page_link =
903 		((unsigned long)imxdmac->sg_list | 0x01) & ~0x02;
904 
905 	desc->type = IMXDMA_DESC_CYCLIC;
906 	desc->sg = imxdmac->sg_list;
907 	desc->sgcount = periods;
908 	desc->len = IMX_DMA_LENGTH_LOOP;
909 	desc->direction = direction;
910 	if (direction == DMA_DEV_TO_MEM) {
911 		desc->src = imxdmac->per_address;
912 	} else {
913 		desc->dest = imxdmac->per_address;
914 	}
915 	desc->desc.callback = NULL;
916 	desc->desc.callback_param = NULL;
917 
918 	return &desc->desc;
919 }
920 
921 static struct dma_async_tx_descriptor *imxdma_prep_dma_memcpy(
922 	struct dma_chan *chan, dma_addr_t dest,
923 	dma_addr_t src, size_t len, unsigned long flags)
924 {
925 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
926 	struct imxdma_engine *imxdma = imxdmac->imxdma;
927 	struct imxdma_desc *desc;
928 
929 	dev_dbg(imxdma->dev, "%s channel: %d src=0x%x dst=0x%x len=%d\n",
930 			__func__, imxdmac->channel, src, dest, len);
931 
932 	if (list_empty(&imxdmac->ld_free) ||
933 	    imxdma_chan_is_doing_cyclic(imxdmac))
934 		return NULL;
935 
936 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
937 
938 	desc->type = IMXDMA_DESC_MEMCPY;
939 	desc->src = src;
940 	desc->dest = dest;
941 	desc->len = len;
942 	desc->direction = DMA_MEM_TO_MEM;
943 	desc->config_port = IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR;
944 	desc->config_mem = IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR;
945 	desc->desc.callback = NULL;
946 	desc->desc.callback_param = NULL;
947 
948 	return &desc->desc;
949 }
950 
951 static struct dma_async_tx_descriptor *imxdma_prep_dma_interleaved(
952 	struct dma_chan *chan, struct dma_interleaved_template *xt,
953 	unsigned long flags)
954 {
955 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
956 	struct imxdma_engine *imxdma = imxdmac->imxdma;
957 	struct imxdma_desc *desc;
958 
959 	dev_dbg(imxdma->dev, "%s channel: %d src_start=0x%x dst_start=0x%x\n"
960 		"   src_sgl=%s dst_sgl=%s numf=%d frame_size=%d\n", __func__,
961 		imxdmac->channel, xt->src_start, xt->dst_start,
962 		xt->src_sgl ? "true" : "false", xt->dst_sgl ? "true" : "false",
963 		xt->numf, xt->frame_size);
964 
965 	if (list_empty(&imxdmac->ld_free) ||
966 	    imxdma_chan_is_doing_cyclic(imxdmac))
967 		return NULL;
968 
969 	if (xt->frame_size != 1 || xt->numf <= 0 || xt->dir != DMA_MEM_TO_MEM)
970 		return NULL;
971 
972 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
973 
974 	desc->type = IMXDMA_DESC_INTERLEAVED;
975 	desc->src = xt->src_start;
976 	desc->dest = xt->dst_start;
977 	desc->x = xt->sgl[0].size;
978 	desc->y = xt->numf;
979 	desc->w = xt->sgl[0].icg + desc->x;
980 	desc->len = desc->x * desc->y;
981 	desc->direction = DMA_MEM_TO_MEM;
982 	desc->config_port = IMX_DMA_MEMSIZE_32;
983 	desc->config_mem = IMX_DMA_MEMSIZE_32;
984 	if (xt->src_sgl)
985 		desc->config_mem |= IMX_DMA_TYPE_2D;
986 	if (xt->dst_sgl)
987 		desc->config_port |= IMX_DMA_TYPE_2D;
988 	desc->desc.callback = NULL;
989 	desc->desc.callback_param = NULL;
990 
991 	return &desc->desc;
992 }
993 
994 static void imxdma_issue_pending(struct dma_chan *chan)
995 {
996 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
997 	struct imxdma_engine *imxdma = imxdmac->imxdma;
998 	struct imxdma_desc *desc;
999 	unsigned long flags;
1000 
1001 	spin_lock_irqsave(&imxdma->lock, flags);
1002 	if (list_empty(&imxdmac->ld_active) &&
1003 	    !list_empty(&imxdmac->ld_queue)) {
1004 		desc = list_first_entry(&imxdmac->ld_queue,
1005 					struct imxdma_desc, node);
1006 
1007 		if (imxdma_xfer_desc(desc) < 0) {
1008 			dev_warn(imxdma->dev,
1009 				 "%s: channel: %d couldn't issue DMA xfer\n",
1010 				 __func__, imxdmac->channel);
1011 		} else {
1012 			list_move_tail(imxdmac->ld_queue.next,
1013 				       &imxdmac->ld_active);
1014 		}
1015 	}
1016 	spin_unlock_irqrestore(&imxdma->lock, flags);
1017 }
1018 
1019 static bool imxdma_filter_fn(struct dma_chan *chan, void *param)
1020 {
1021 	struct imxdma_filter_data *fdata = param;
1022 	struct imxdma_channel *imxdma_chan = to_imxdma_chan(chan);
1023 
1024 	if (chan->device->dev != fdata->imxdma->dev)
1025 		return false;
1026 
1027 	imxdma_chan->dma_request = fdata->request;
1028 	chan->private = NULL;
1029 
1030 	return true;
1031 }
1032 
1033 static struct dma_chan *imxdma_xlate(struct of_phandle_args *dma_spec,
1034 						struct of_dma *ofdma)
1035 {
1036 	int count = dma_spec->args_count;
1037 	struct imxdma_engine *imxdma = ofdma->of_dma_data;
1038 	struct imxdma_filter_data fdata = {
1039 		.imxdma = imxdma,
1040 	};
1041 
1042 	if (count != 1)
1043 		return NULL;
1044 
1045 	fdata.request = dma_spec->args[0];
1046 
1047 	return dma_request_channel(imxdma->dma_device.cap_mask,
1048 					imxdma_filter_fn, &fdata);
1049 }
1050 
1051 static int __init imxdma_probe(struct platform_device *pdev)
1052 	{
1053 	struct imxdma_engine *imxdma;
1054 	struct resource *res;
1055 	const struct of_device_id *of_id;
1056 	int ret, i;
1057 	int irq, irq_err;
1058 
1059 	of_id = of_match_device(imx_dma_of_dev_id, &pdev->dev);
1060 	if (of_id)
1061 		pdev->id_entry = of_id->data;
1062 
1063 	imxdma = devm_kzalloc(&pdev->dev, sizeof(*imxdma), GFP_KERNEL);
1064 	if (!imxdma)
1065 		return -ENOMEM;
1066 
1067 	imxdma->dev = &pdev->dev;
1068 	imxdma->devtype = pdev->id_entry->driver_data;
1069 
1070 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1071 	imxdma->base = devm_ioremap_resource(&pdev->dev, res);
1072 	if (IS_ERR(imxdma->base))
1073 		return PTR_ERR(imxdma->base);
1074 
1075 	irq = platform_get_irq(pdev, 0);
1076 	if (irq < 0)
1077 		return irq;
1078 
1079 	imxdma->dma_ipg = devm_clk_get(&pdev->dev, "ipg");
1080 	if (IS_ERR(imxdma->dma_ipg))
1081 		return PTR_ERR(imxdma->dma_ipg);
1082 
1083 	imxdma->dma_ahb = devm_clk_get(&pdev->dev, "ahb");
1084 	if (IS_ERR(imxdma->dma_ahb))
1085 		return PTR_ERR(imxdma->dma_ahb);
1086 
1087 	clk_prepare_enable(imxdma->dma_ipg);
1088 	clk_prepare_enable(imxdma->dma_ahb);
1089 
1090 	/* reset DMA module */
1091 	imx_dmav1_writel(imxdma, DCR_DRST, DMA_DCR);
1092 
1093 	if (is_imx1_dma(imxdma)) {
1094 		ret = devm_request_irq(&pdev->dev, irq,
1095 				       dma_irq_handler, 0, "DMA", imxdma);
1096 		if (ret) {
1097 			dev_warn(imxdma->dev, "Can't register IRQ for DMA\n");
1098 			goto err;
1099 		}
1100 
1101 		irq_err = platform_get_irq(pdev, 1);
1102 		if (irq_err < 0) {
1103 			ret = irq_err;
1104 			goto err;
1105 		}
1106 
1107 		ret = devm_request_irq(&pdev->dev, irq_err,
1108 				       imxdma_err_handler, 0, "DMA", imxdma);
1109 		if (ret) {
1110 			dev_warn(imxdma->dev, "Can't register ERRIRQ for DMA\n");
1111 			goto err;
1112 		}
1113 	}
1114 
1115 	/* enable DMA module */
1116 	imx_dmav1_writel(imxdma, DCR_DEN, DMA_DCR);
1117 
1118 	/* clear all interrupts */
1119 	imx_dmav1_writel(imxdma, (1 << IMX_DMA_CHANNELS) - 1, DMA_DISR);
1120 
1121 	/* disable interrupts */
1122 	imx_dmav1_writel(imxdma, (1 << IMX_DMA_CHANNELS) - 1, DMA_DIMR);
1123 
1124 	INIT_LIST_HEAD(&imxdma->dma_device.channels);
1125 
1126 	dma_cap_set(DMA_SLAVE, imxdma->dma_device.cap_mask);
1127 	dma_cap_set(DMA_CYCLIC, imxdma->dma_device.cap_mask);
1128 	dma_cap_set(DMA_MEMCPY, imxdma->dma_device.cap_mask);
1129 	dma_cap_set(DMA_INTERLEAVE, imxdma->dma_device.cap_mask);
1130 
1131 	/* Initialize 2D global parameters */
1132 	for (i = 0; i < IMX_DMA_2D_SLOTS; i++)
1133 		imxdma->slots_2d[i].count = 0;
1134 
1135 	spin_lock_init(&imxdma->lock);
1136 
1137 	/* Initialize channel parameters */
1138 	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
1139 		struct imxdma_channel *imxdmac = &imxdma->channel[i];
1140 
1141 		if (!is_imx1_dma(imxdma)) {
1142 			ret = devm_request_irq(&pdev->dev, irq + i,
1143 					dma_irq_handler, 0, "DMA", imxdma);
1144 			if (ret) {
1145 				dev_warn(imxdma->dev, "Can't register IRQ %d "
1146 					 "for DMA channel %d\n",
1147 					 irq + i, i);
1148 				goto err;
1149 			}
1150 			init_timer(&imxdmac->watchdog);
1151 			imxdmac->watchdog.function = &imxdma_watchdog;
1152 			imxdmac->watchdog.data = (unsigned long)imxdmac;
1153 		}
1154 
1155 		imxdmac->imxdma = imxdma;
1156 
1157 		INIT_LIST_HEAD(&imxdmac->ld_queue);
1158 		INIT_LIST_HEAD(&imxdmac->ld_free);
1159 		INIT_LIST_HEAD(&imxdmac->ld_active);
1160 
1161 		tasklet_init(&imxdmac->dma_tasklet, imxdma_tasklet,
1162 			     (unsigned long)imxdmac);
1163 		imxdmac->chan.device = &imxdma->dma_device;
1164 		dma_cookie_init(&imxdmac->chan);
1165 		imxdmac->channel = i;
1166 
1167 		/* Add the channel to the DMAC list */
1168 		list_add_tail(&imxdmac->chan.device_node,
1169 			      &imxdma->dma_device.channels);
1170 	}
1171 
1172 	imxdma->dma_device.dev = &pdev->dev;
1173 
1174 	imxdma->dma_device.device_alloc_chan_resources = imxdma_alloc_chan_resources;
1175 	imxdma->dma_device.device_free_chan_resources = imxdma_free_chan_resources;
1176 	imxdma->dma_device.device_tx_status = imxdma_tx_status;
1177 	imxdma->dma_device.device_prep_slave_sg = imxdma_prep_slave_sg;
1178 	imxdma->dma_device.device_prep_dma_cyclic = imxdma_prep_dma_cyclic;
1179 	imxdma->dma_device.device_prep_dma_memcpy = imxdma_prep_dma_memcpy;
1180 	imxdma->dma_device.device_prep_interleaved_dma = imxdma_prep_dma_interleaved;
1181 	imxdma->dma_device.device_control = imxdma_control;
1182 	imxdma->dma_device.device_issue_pending = imxdma_issue_pending;
1183 
1184 	platform_set_drvdata(pdev, imxdma);
1185 
1186 	imxdma->dma_device.copy_align = 2; /* 2^2 = 4 bytes alignment */
1187 	imxdma->dma_device.dev->dma_parms = &imxdma->dma_parms;
1188 	dma_set_max_seg_size(imxdma->dma_device.dev, 0xffffff);
1189 
1190 	ret = dma_async_device_register(&imxdma->dma_device);
1191 	if (ret) {
1192 		dev_err(&pdev->dev, "unable to register\n");
1193 		goto err;
1194 	}
1195 
1196 	if (pdev->dev.of_node) {
1197 		ret = of_dma_controller_register(pdev->dev.of_node,
1198 				imxdma_xlate, imxdma);
1199 		if (ret) {
1200 			dev_err(&pdev->dev, "unable to register of_dma_controller\n");
1201 			goto err_of_dma_controller;
1202 		}
1203 	}
1204 
1205 	return 0;
1206 
1207 err_of_dma_controller:
1208 	dma_async_device_unregister(&imxdma->dma_device);
1209 err:
1210 	clk_disable_unprepare(imxdma->dma_ipg);
1211 	clk_disable_unprepare(imxdma->dma_ahb);
1212 	return ret;
1213 }
1214 
1215 static int imxdma_remove(struct platform_device *pdev)
1216 {
1217 	struct imxdma_engine *imxdma = platform_get_drvdata(pdev);
1218 
1219         dma_async_device_unregister(&imxdma->dma_device);
1220 
1221 	if (pdev->dev.of_node)
1222 		of_dma_controller_free(pdev->dev.of_node);
1223 
1224 	clk_disable_unprepare(imxdma->dma_ipg);
1225 	clk_disable_unprepare(imxdma->dma_ahb);
1226 
1227         return 0;
1228 }
1229 
1230 static struct platform_driver imxdma_driver = {
1231 	.driver		= {
1232 		.name	= "imx-dma",
1233 		.of_match_table = imx_dma_of_dev_id,
1234 	},
1235 	.id_table	= imx_dma_devtype,
1236 	.remove		= imxdma_remove,
1237 };
1238 
1239 static int __init imxdma_module_init(void)
1240 {
1241 	return platform_driver_probe(&imxdma_driver, imxdma_probe);
1242 }
1243 subsys_initcall(imxdma_module_init);
1244 
1245 MODULE_AUTHOR("Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>");
1246 MODULE_DESCRIPTION("i.MX dma driver");
1247 MODULE_LICENSE("GPL");
1248