xref: /openbmc/linux/drivers/dma/imx-dma.c (revision 63dc02bd)
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/init.h>
18 #include <linux/types.h>
19 #include <linux/mm.h>
20 #include <linux/interrupt.h>
21 #include <linux/spinlock.h>
22 #include <linux/device.h>
23 #include <linux/dma-mapping.h>
24 #include <linux/slab.h>
25 #include <linux/platform_device.h>
26 #include <linux/clk.h>
27 #include <linux/dmaengine.h>
28 #include <linux/module.h>
29 
30 #include <asm/irq.h>
31 #include <mach/dma.h>
32 #include <mach/hardware.h>
33 
34 #include "dmaengine.h"
35 #define IMXDMA_MAX_CHAN_DESCRIPTORS	16
36 #define IMX_DMA_CHANNELS  16
37 
38 #define IMX_DMA_2D_SLOTS	2
39 #define IMX_DMA_2D_SLOT_A	0
40 #define IMX_DMA_2D_SLOT_B	1
41 
42 #define IMX_DMA_LENGTH_LOOP	((unsigned int)-1)
43 #define IMX_DMA_MEMSIZE_32	(0 << 4)
44 #define IMX_DMA_MEMSIZE_8	(1 << 4)
45 #define IMX_DMA_MEMSIZE_16	(2 << 4)
46 #define IMX_DMA_TYPE_LINEAR	(0 << 10)
47 #define IMX_DMA_TYPE_2D		(1 << 10)
48 #define IMX_DMA_TYPE_FIFO	(2 << 10)
49 
50 #define IMX_DMA_ERR_BURST     (1 << 0)
51 #define IMX_DMA_ERR_REQUEST   (1 << 1)
52 #define IMX_DMA_ERR_TRANSFER  (1 << 2)
53 #define IMX_DMA_ERR_BUFFER    (1 << 3)
54 #define IMX_DMA_ERR_TIMEOUT   (1 << 4)
55 
56 #define DMA_DCR     0x00		/* Control Register */
57 #define DMA_DISR    0x04		/* Interrupt status Register */
58 #define DMA_DIMR    0x08		/* Interrupt mask Register */
59 #define DMA_DBTOSR  0x0c		/* Burst timeout status Register */
60 #define DMA_DRTOSR  0x10		/* Request timeout Register */
61 #define DMA_DSESR   0x14		/* Transfer Error Status Register */
62 #define DMA_DBOSR   0x18		/* Buffer overflow status Register */
63 #define DMA_DBTOCR  0x1c		/* Burst timeout control Register */
64 #define DMA_WSRA    0x40		/* W-Size Register A */
65 #define DMA_XSRA    0x44		/* X-Size Register A */
66 #define DMA_YSRA    0x48		/* Y-Size Register A */
67 #define DMA_WSRB    0x4c		/* W-Size Register B */
68 #define DMA_XSRB    0x50		/* X-Size Register B */
69 #define DMA_YSRB    0x54		/* Y-Size Register B */
70 #define DMA_SAR(x)  (0x80 + ((x) << 6))	/* Source Address Registers */
71 #define DMA_DAR(x)  (0x84 + ((x) << 6))	/* Destination Address Registers */
72 #define DMA_CNTR(x) (0x88 + ((x) << 6))	/* Count Registers */
73 #define DMA_CCR(x)  (0x8c + ((x) << 6))	/* Control Registers */
74 #define DMA_RSSR(x) (0x90 + ((x) << 6))	/* Request source select Registers */
75 #define DMA_BLR(x)  (0x94 + ((x) << 6))	/* Burst length Registers */
76 #define DMA_RTOR(x) (0x98 + ((x) << 6))	/* Request timeout Registers */
77 #define DMA_BUCR(x) (0x98 + ((x) << 6))	/* Bus Utilization Registers */
78 #define DMA_CCNR(x) (0x9C + ((x) << 6))	/* Channel counter Registers */
79 
80 #define DCR_DRST           (1<<1)
81 #define DCR_DEN            (1<<0)
82 #define DBTOCR_EN          (1<<15)
83 #define DBTOCR_CNT(x)      ((x) & 0x7fff)
84 #define CNTR_CNT(x)        ((x) & 0xffffff)
85 #define CCR_ACRPT          (1<<14)
86 #define CCR_DMOD_LINEAR    (0x0 << 12)
87 #define CCR_DMOD_2D        (0x1 << 12)
88 #define CCR_DMOD_FIFO      (0x2 << 12)
89 #define CCR_DMOD_EOBFIFO   (0x3 << 12)
90 #define CCR_SMOD_LINEAR    (0x0 << 10)
91 #define CCR_SMOD_2D        (0x1 << 10)
92 #define CCR_SMOD_FIFO      (0x2 << 10)
93 #define CCR_SMOD_EOBFIFO   (0x3 << 10)
94 #define CCR_MDIR_DEC       (1<<9)
95 #define CCR_MSEL_B         (1<<8)
96 #define CCR_DSIZ_32        (0x0 << 6)
97 #define CCR_DSIZ_8         (0x1 << 6)
98 #define CCR_DSIZ_16        (0x2 << 6)
99 #define CCR_SSIZ_32        (0x0 << 4)
100 #define CCR_SSIZ_8         (0x1 << 4)
101 #define CCR_SSIZ_16        (0x2 << 4)
102 #define CCR_REN            (1<<3)
103 #define CCR_RPT            (1<<2)
104 #define CCR_FRC            (1<<1)
105 #define CCR_CEN            (1<<0)
106 #define RTOR_EN            (1<<15)
107 #define RTOR_CLK           (1<<14)
108 #define RTOR_PSC           (1<<13)
109 
110 enum  imxdma_prep_type {
111 	IMXDMA_DESC_MEMCPY,
112 	IMXDMA_DESC_INTERLEAVED,
113 	IMXDMA_DESC_SLAVE_SG,
114 	IMXDMA_DESC_CYCLIC,
115 };
116 
117 struct imx_dma_2d_config {
118 	u16		xsr;
119 	u16		ysr;
120 	u16		wsr;
121 	int		count;
122 };
123 
124 struct imxdma_desc {
125 	struct list_head		node;
126 	struct dma_async_tx_descriptor	desc;
127 	enum dma_status			status;
128 	dma_addr_t			src;
129 	dma_addr_t			dest;
130 	size_t				len;
131 	enum dma_transfer_direction	direction;
132 	enum imxdma_prep_type		type;
133 	/* For memcpy and interleaved */
134 	unsigned int			config_port;
135 	unsigned int			config_mem;
136 	/* For interleaved transfers */
137 	unsigned int			x;
138 	unsigned int			y;
139 	unsigned int			w;
140 	/* For slave sg and cyclic */
141 	struct scatterlist		*sg;
142 	unsigned int			sgcount;
143 };
144 
145 struct imxdma_channel {
146 	int				hw_chaining;
147 	struct timer_list		watchdog;
148 	struct imxdma_engine		*imxdma;
149 	unsigned int			channel;
150 
151 	struct tasklet_struct		dma_tasklet;
152 	struct list_head		ld_free;
153 	struct list_head		ld_queue;
154 	struct list_head		ld_active;
155 	int				descs_allocated;
156 	enum dma_slave_buswidth		word_size;
157 	dma_addr_t			per_address;
158 	u32				watermark_level;
159 	struct dma_chan			chan;
160 	struct dma_async_tx_descriptor	desc;
161 	enum dma_status			status;
162 	int				dma_request;
163 	struct scatterlist		*sg_list;
164 	u32				ccr_from_device;
165 	u32				ccr_to_device;
166 	bool				enabled_2d;
167 	int				slot_2d;
168 };
169 
170 struct imxdma_engine {
171 	struct device			*dev;
172 	struct device_dma_parameters	dma_parms;
173 	struct dma_device		dma_device;
174 	void __iomem			*base;
175 	struct clk			*dma_clk;
176 	spinlock_t			lock;
177 	struct imx_dma_2d_config	slots_2d[IMX_DMA_2D_SLOTS];
178 	struct imxdma_channel		channel[IMX_DMA_CHANNELS];
179 };
180 
181 static struct imxdma_channel *to_imxdma_chan(struct dma_chan *chan)
182 {
183 	return container_of(chan, struct imxdma_channel, chan);
184 }
185 
186 static inline bool imxdma_chan_is_doing_cyclic(struct imxdma_channel *imxdmac)
187 {
188 	struct imxdma_desc *desc;
189 
190 	if (!list_empty(&imxdmac->ld_active)) {
191 		desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc,
192 					node);
193 		if (desc->type == IMXDMA_DESC_CYCLIC)
194 			return true;
195 	}
196 	return false;
197 }
198 
199 
200 
201 static void imx_dmav1_writel(struct imxdma_engine *imxdma, unsigned val,
202 			     unsigned offset)
203 {
204 	__raw_writel(val, imxdma->base + offset);
205 }
206 
207 static unsigned imx_dmav1_readl(struct imxdma_engine *imxdma, unsigned offset)
208 {
209 	return __raw_readl(imxdma->base + offset);
210 }
211 
212 static int imxdma_hw_chain(struct imxdma_channel *imxdmac)
213 {
214 	if (cpu_is_mx27())
215 		return imxdmac->hw_chaining;
216 	else
217 		return 0;
218 }
219 
220 /*
221  * imxdma_sg_next - prepare next chunk for scatter-gather DMA emulation
222  */
223 static inline int imxdma_sg_next(struct imxdma_desc *d)
224 {
225 	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
226 	struct imxdma_engine *imxdma = imxdmac->imxdma;
227 	struct scatterlist *sg = d->sg;
228 	unsigned long now;
229 
230 	now = min(d->len, sg->length);
231 	if (d->len != IMX_DMA_LENGTH_LOOP)
232 		d->len -= now;
233 
234 	if (d->direction == DMA_DEV_TO_MEM)
235 		imx_dmav1_writel(imxdma, sg->dma_address,
236 				 DMA_DAR(imxdmac->channel));
237 	else
238 		imx_dmav1_writel(imxdma, sg->dma_address,
239 				 DMA_SAR(imxdmac->channel));
240 
241 	imx_dmav1_writel(imxdma, now, DMA_CNTR(imxdmac->channel));
242 
243 	dev_dbg(imxdma->dev, " %s channel: %d dst 0x%08x, src 0x%08x, "
244 		"size 0x%08x\n", __func__, imxdmac->channel,
245 		 imx_dmav1_readl(imxdma, DMA_DAR(imxdmac->channel)),
246 		 imx_dmav1_readl(imxdma, DMA_SAR(imxdmac->channel)),
247 		 imx_dmav1_readl(imxdma, DMA_CNTR(imxdmac->channel)));
248 
249 	return now;
250 }
251 
252 static void imxdma_enable_hw(struct imxdma_desc *d)
253 {
254 	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
255 	struct imxdma_engine *imxdma = imxdmac->imxdma;
256 	int channel = imxdmac->channel;
257 	unsigned long flags;
258 
259 	dev_dbg(imxdma->dev, "%s channel %d\n", __func__, channel);
260 
261 	local_irq_save(flags);
262 
263 	imx_dmav1_writel(imxdma, 1 << channel, DMA_DISR);
264 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_DIMR) &
265 			 ~(1 << channel), DMA_DIMR);
266 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_CCR(channel)) |
267 			 CCR_CEN | CCR_ACRPT, DMA_CCR(channel));
268 
269 	if ((cpu_is_mx21() || cpu_is_mx27()) &&
270 			d->sg && imxdma_hw_chain(imxdmac)) {
271 		d->sg = sg_next(d->sg);
272 		if (d->sg) {
273 			u32 tmp;
274 			imxdma_sg_next(d);
275 			tmp = imx_dmav1_readl(imxdma, DMA_CCR(channel));
276 			imx_dmav1_writel(imxdma, tmp | CCR_RPT | CCR_ACRPT,
277 					 DMA_CCR(channel));
278 		}
279 	}
280 
281 	local_irq_restore(flags);
282 }
283 
284 static void imxdma_disable_hw(struct imxdma_channel *imxdmac)
285 {
286 	struct imxdma_engine *imxdma = imxdmac->imxdma;
287 	int channel = imxdmac->channel;
288 	unsigned long flags;
289 
290 	dev_dbg(imxdma->dev, "%s channel %d\n", __func__, channel);
291 
292 	if (imxdma_hw_chain(imxdmac))
293 		del_timer(&imxdmac->watchdog);
294 
295 	local_irq_save(flags);
296 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_DIMR) |
297 			 (1 << channel), DMA_DIMR);
298 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_CCR(channel)) &
299 			 ~CCR_CEN, DMA_CCR(channel));
300 	imx_dmav1_writel(imxdma, 1 << channel, DMA_DISR);
301 	local_irq_restore(flags);
302 }
303 
304 static void imxdma_watchdog(unsigned long data)
305 {
306 	struct imxdma_channel *imxdmac = (struct imxdma_channel *)data;
307 	struct imxdma_engine *imxdma = imxdmac->imxdma;
308 	int channel = imxdmac->channel;
309 
310 	imx_dmav1_writel(imxdma, 0, DMA_CCR(channel));
311 
312 	/* Tasklet watchdog error handler */
313 	tasklet_schedule(&imxdmac->dma_tasklet);
314 	dev_dbg(imxdma->dev, "channel %d: watchdog timeout!\n",
315 		imxdmac->channel);
316 }
317 
318 static irqreturn_t imxdma_err_handler(int irq, void *dev_id)
319 {
320 	struct imxdma_engine *imxdma = dev_id;
321 	unsigned int err_mask;
322 	int i, disr;
323 	int errcode;
324 
325 	disr = imx_dmav1_readl(imxdma, DMA_DISR);
326 
327 	err_mask = imx_dmav1_readl(imxdma, DMA_DBTOSR) |
328 		   imx_dmav1_readl(imxdma, DMA_DRTOSR) |
329 		   imx_dmav1_readl(imxdma, DMA_DSESR)  |
330 		   imx_dmav1_readl(imxdma, DMA_DBOSR);
331 
332 	if (!err_mask)
333 		return IRQ_HANDLED;
334 
335 	imx_dmav1_writel(imxdma, disr & err_mask, DMA_DISR);
336 
337 	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
338 		if (!(err_mask & (1 << i)))
339 			continue;
340 		errcode = 0;
341 
342 		if (imx_dmav1_readl(imxdma, DMA_DBTOSR) & (1 << i)) {
343 			imx_dmav1_writel(imxdma, 1 << i, DMA_DBTOSR);
344 			errcode |= IMX_DMA_ERR_BURST;
345 		}
346 		if (imx_dmav1_readl(imxdma, DMA_DRTOSR) & (1 << i)) {
347 			imx_dmav1_writel(imxdma, 1 << i, DMA_DRTOSR);
348 			errcode |= IMX_DMA_ERR_REQUEST;
349 		}
350 		if (imx_dmav1_readl(imxdma, DMA_DSESR) & (1 << i)) {
351 			imx_dmav1_writel(imxdma, 1 << i, DMA_DSESR);
352 			errcode |= IMX_DMA_ERR_TRANSFER;
353 		}
354 		if (imx_dmav1_readl(imxdma, DMA_DBOSR) & (1 << i)) {
355 			imx_dmav1_writel(imxdma, 1 << i, DMA_DBOSR);
356 			errcode |= IMX_DMA_ERR_BUFFER;
357 		}
358 		/* Tasklet error handler */
359 		tasklet_schedule(&imxdma->channel[i].dma_tasklet);
360 
361 		printk(KERN_WARNING
362 		       "DMA timeout on channel %d -%s%s%s%s\n", i,
363 		       errcode & IMX_DMA_ERR_BURST ?    " burst" : "",
364 		       errcode & IMX_DMA_ERR_REQUEST ?  " request" : "",
365 		       errcode & IMX_DMA_ERR_TRANSFER ? " transfer" : "",
366 		       errcode & IMX_DMA_ERR_BUFFER ?   " buffer" : "");
367 	}
368 	return IRQ_HANDLED;
369 }
370 
371 static void dma_irq_handle_channel(struct imxdma_channel *imxdmac)
372 {
373 	struct imxdma_engine *imxdma = imxdmac->imxdma;
374 	int chno = imxdmac->channel;
375 	struct imxdma_desc *desc;
376 
377 	spin_lock(&imxdma->lock);
378 	if (list_empty(&imxdmac->ld_active)) {
379 		spin_unlock(&imxdma->lock);
380 		goto out;
381 	}
382 
383 	desc = list_first_entry(&imxdmac->ld_active,
384 				struct imxdma_desc,
385 				node);
386 	spin_unlock(&imxdma->lock);
387 
388 	if (desc->sg) {
389 		u32 tmp;
390 		desc->sg = sg_next(desc->sg);
391 
392 		if (desc->sg) {
393 			imxdma_sg_next(desc);
394 
395 			tmp = imx_dmav1_readl(imxdma, DMA_CCR(chno));
396 
397 			if (imxdma_hw_chain(imxdmac)) {
398 				/* FIXME: The timeout should probably be
399 				 * configurable
400 				 */
401 				mod_timer(&imxdmac->watchdog,
402 					jiffies + msecs_to_jiffies(500));
403 
404 				tmp |= CCR_CEN | CCR_RPT | CCR_ACRPT;
405 				imx_dmav1_writel(imxdma, tmp, DMA_CCR(chno));
406 			} else {
407 				imx_dmav1_writel(imxdma, tmp & ~CCR_CEN,
408 						 DMA_CCR(chno));
409 				tmp |= CCR_CEN;
410 			}
411 
412 			imx_dmav1_writel(imxdma, tmp, DMA_CCR(chno));
413 
414 			if (imxdma_chan_is_doing_cyclic(imxdmac))
415 				/* Tasklet progression */
416 				tasklet_schedule(&imxdmac->dma_tasklet);
417 
418 			return;
419 		}
420 
421 		if (imxdma_hw_chain(imxdmac)) {
422 			del_timer(&imxdmac->watchdog);
423 			return;
424 		}
425 	}
426 
427 out:
428 	imx_dmav1_writel(imxdma, 0, DMA_CCR(chno));
429 	/* Tasklet irq */
430 	tasklet_schedule(&imxdmac->dma_tasklet);
431 }
432 
433 static irqreturn_t dma_irq_handler(int irq, void *dev_id)
434 {
435 	struct imxdma_engine *imxdma = dev_id;
436 	int i, disr;
437 
438 	if (cpu_is_mx21() || cpu_is_mx27())
439 		imxdma_err_handler(irq, dev_id);
440 
441 	disr = imx_dmav1_readl(imxdma, DMA_DISR);
442 
443 	dev_dbg(imxdma->dev, "%s called, disr=0x%08x\n", __func__, disr);
444 
445 	imx_dmav1_writel(imxdma, disr, DMA_DISR);
446 	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
447 		if (disr & (1 << i))
448 			dma_irq_handle_channel(&imxdma->channel[i]);
449 	}
450 
451 	return IRQ_HANDLED;
452 }
453 
454 static int imxdma_xfer_desc(struct imxdma_desc *d)
455 {
456 	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
457 	struct imxdma_engine *imxdma = imxdmac->imxdma;
458 	unsigned long flags;
459 	int slot = -1;
460 	int i;
461 
462 	/* Configure and enable */
463 	switch (d->type) {
464 	case IMXDMA_DESC_INTERLEAVED:
465 		/* Try to get a free 2D slot */
466 		spin_lock_irqsave(&imxdma->lock, flags);
467 		for (i = 0; i < IMX_DMA_2D_SLOTS; i++) {
468 			if ((imxdma->slots_2d[i].count > 0) &&
469 			((imxdma->slots_2d[i].xsr != d->x) ||
470 			(imxdma->slots_2d[i].ysr != d->y) ||
471 			(imxdma->slots_2d[i].wsr != d->w)))
472 				continue;
473 			slot = i;
474 			break;
475 		}
476 		if (slot < 0)
477 			return -EBUSY;
478 
479 		imxdma->slots_2d[slot].xsr = d->x;
480 		imxdma->slots_2d[slot].ysr = d->y;
481 		imxdma->slots_2d[slot].wsr = d->w;
482 		imxdma->slots_2d[slot].count++;
483 
484 		imxdmac->slot_2d = slot;
485 		imxdmac->enabled_2d = true;
486 		spin_unlock_irqrestore(&imxdma->lock, flags);
487 
488 		if (slot == IMX_DMA_2D_SLOT_A) {
489 			d->config_mem &= ~CCR_MSEL_B;
490 			d->config_port &= ~CCR_MSEL_B;
491 			imx_dmav1_writel(imxdma, d->x, DMA_XSRA);
492 			imx_dmav1_writel(imxdma, d->y, DMA_YSRA);
493 			imx_dmav1_writel(imxdma, d->w, DMA_WSRA);
494 		} else {
495 			d->config_mem |= CCR_MSEL_B;
496 			d->config_port |= CCR_MSEL_B;
497 			imx_dmav1_writel(imxdma, d->x, DMA_XSRB);
498 			imx_dmav1_writel(imxdma, d->y, DMA_YSRB);
499 			imx_dmav1_writel(imxdma, d->w, DMA_WSRB);
500 		}
501 		/*
502 		 * We fall-through here intentionally, since a 2D transfer is
503 		 * similar to MEMCPY just adding the 2D slot configuration.
504 		 */
505 	case IMXDMA_DESC_MEMCPY:
506 		imx_dmav1_writel(imxdma, d->src, DMA_SAR(imxdmac->channel));
507 		imx_dmav1_writel(imxdma, d->dest, DMA_DAR(imxdmac->channel));
508 		imx_dmav1_writel(imxdma, d->config_mem | (d->config_port << 2),
509 			 DMA_CCR(imxdmac->channel));
510 
511 		imx_dmav1_writel(imxdma, d->len, DMA_CNTR(imxdmac->channel));
512 
513 		dev_dbg(imxdma->dev, "%s channel: %d dest=0x%08x src=0x%08x "
514 			"dma_length=%d\n", __func__, imxdmac->channel,
515 			d->dest, d->src, d->len);
516 
517 		break;
518 	/* Cyclic transfer is the same as slave_sg with special sg configuration. */
519 	case IMXDMA_DESC_CYCLIC:
520 	case IMXDMA_DESC_SLAVE_SG:
521 		if (d->direction == DMA_DEV_TO_MEM) {
522 			imx_dmav1_writel(imxdma, imxdmac->per_address,
523 					 DMA_SAR(imxdmac->channel));
524 			imx_dmav1_writel(imxdma, imxdmac->ccr_from_device,
525 					 DMA_CCR(imxdmac->channel));
526 
527 			dev_dbg(imxdma->dev, "%s channel: %d sg=%p sgcount=%d "
528 				"total length=%d dev_addr=0x%08x (dev2mem)\n",
529 				__func__, imxdmac->channel, d->sg, d->sgcount,
530 				d->len, imxdmac->per_address);
531 		} else if (d->direction == DMA_MEM_TO_DEV) {
532 			imx_dmav1_writel(imxdma, imxdmac->per_address,
533 					 DMA_DAR(imxdmac->channel));
534 			imx_dmav1_writel(imxdma, imxdmac->ccr_to_device,
535 					 DMA_CCR(imxdmac->channel));
536 
537 			dev_dbg(imxdma->dev, "%s channel: %d sg=%p sgcount=%d "
538 				"total length=%d dev_addr=0x%08x (mem2dev)\n",
539 				__func__, imxdmac->channel, d->sg, d->sgcount,
540 				d->len, imxdmac->per_address);
541 		} else {
542 			dev_err(imxdma->dev, "%s channel: %d bad dma mode\n",
543 				__func__, imxdmac->channel);
544 			return -EINVAL;
545 		}
546 
547 		imxdma_sg_next(d);
548 
549 		break;
550 	default:
551 		return -EINVAL;
552 	}
553 	imxdma_enable_hw(d);
554 	return 0;
555 }
556 
557 static void imxdma_tasklet(unsigned long data)
558 {
559 	struct imxdma_channel *imxdmac = (void *)data;
560 	struct imxdma_engine *imxdma = imxdmac->imxdma;
561 	struct imxdma_desc *desc;
562 
563 	spin_lock(&imxdma->lock);
564 
565 	if (list_empty(&imxdmac->ld_active)) {
566 		/* Someone might have called terminate all */
567 		goto out;
568 	}
569 	desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc, node);
570 
571 	if (desc->desc.callback)
572 		desc->desc.callback(desc->desc.callback_param);
573 
574 	/* If we are dealing with a cyclic descriptor keep it on ld_active
575 	 * and dont mark the descripor as complete.
576 	 * Only in non-cyclic cases it would be marked as complete
577 	 */
578 	if (imxdma_chan_is_doing_cyclic(imxdmac))
579 		goto out;
580 	else
581 		dma_cookie_complete(&desc->desc);
582 
583 	/* Free 2D slot if it was an interleaved transfer */
584 	if (imxdmac->enabled_2d) {
585 		imxdma->slots_2d[imxdmac->slot_2d].count--;
586 		imxdmac->enabled_2d = false;
587 	}
588 
589 	list_move_tail(imxdmac->ld_active.next, &imxdmac->ld_free);
590 
591 	if (!list_empty(&imxdmac->ld_queue)) {
592 		desc = list_first_entry(&imxdmac->ld_queue, struct imxdma_desc,
593 					node);
594 		list_move_tail(imxdmac->ld_queue.next, &imxdmac->ld_active);
595 		if (imxdma_xfer_desc(desc) < 0)
596 			dev_warn(imxdma->dev, "%s: channel: %d couldn't xfer desc\n",
597 				 __func__, imxdmac->channel);
598 	}
599 out:
600 	spin_unlock(&imxdma->lock);
601 }
602 
603 static int imxdma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
604 		unsigned long arg)
605 {
606 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
607 	struct dma_slave_config *dmaengine_cfg = (void *)arg;
608 	struct imxdma_engine *imxdma = imxdmac->imxdma;
609 	unsigned long flags;
610 	unsigned int mode = 0;
611 
612 	switch (cmd) {
613 	case DMA_TERMINATE_ALL:
614 		imxdma_disable_hw(imxdmac);
615 
616 		spin_lock_irqsave(&imxdma->lock, flags);
617 		list_splice_tail_init(&imxdmac->ld_active, &imxdmac->ld_free);
618 		list_splice_tail_init(&imxdmac->ld_queue, &imxdmac->ld_free);
619 		spin_unlock_irqrestore(&imxdma->lock, flags);
620 		return 0;
621 	case DMA_SLAVE_CONFIG:
622 		if (dmaengine_cfg->direction == DMA_DEV_TO_MEM) {
623 			imxdmac->per_address = dmaengine_cfg->src_addr;
624 			imxdmac->watermark_level = dmaengine_cfg->src_maxburst;
625 			imxdmac->word_size = dmaengine_cfg->src_addr_width;
626 		} else {
627 			imxdmac->per_address = dmaengine_cfg->dst_addr;
628 			imxdmac->watermark_level = dmaengine_cfg->dst_maxburst;
629 			imxdmac->word_size = dmaengine_cfg->dst_addr_width;
630 		}
631 
632 		switch (imxdmac->word_size) {
633 		case DMA_SLAVE_BUSWIDTH_1_BYTE:
634 			mode = IMX_DMA_MEMSIZE_8;
635 			break;
636 		case DMA_SLAVE_BUSWIDTH_2_BYTES:
637 			mode = IMX_DMA_MEMSIZE_16;
638 			break;
639 		default:
640 		case DMA_SLAVE_BUSWIDTH_4_BYTES:
641 			mode = IMX_DMA_MEMSIZE_32;
642 			break;
643 		}
644 
645 		imxdmac->hw_chaining = 1;
646 		if (!imxdma_hw_chain(imxdmac))
647 			return -EINVAL;
648 		imxdmac->ccr_from_device = (mode | IMX_DMA_TYPE_FIFO) |
649 			((IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) << 2) |
650 			CCR_REN;
651 		imxdmac->ccr_to_device =
652 			(IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) |
653 			((mode | IMX_DMA_TYPE_FIFO) << 2) | CCR_REN;
654 		imx_dmav1_writel(imxdma, imxdmac->dma_request,
655 				 DMA_RSSR(imxdmac->channel));
656 
657 		/* Set burst length */
658 		imx_dmav1_writel(imxdma, imxdmac->watermark_level *
659 				imxdmac->word_size, DMA_BLR(imxdmac->channel));
660 
661 		return 0;
662 	default:
663 		return -ENOSYS;
664 	}
665 
666 	return -EINVAL;
667 }
668 
669 static enum dma_status imxdma_tx_status(struct dma_chan *chan,
670 					    dma_cookie_t cookie,
671 					    struct dma_tx_state *txstate)
672 {
673 	return dma_cookie_status(chan, cookie, txstate);
674 }
675 
676 static dma_cookie_t imxdma_tx_submit(struct dma_async_tx_descriptor *tx)
677 {
678 	struct imxdma_channel *imxdmac = to_imxdma_chan(tx->chan);
679 	struct imxdma_engine *imxdma = imxdmac->imxdma;
680 	dma_cookie_t cookie;
681 	unsigned long flags;
682 
683 	spin_lock_irqsave(&imxdma->lock, flags);
684 	list_move_tail(imxdmac->ld_free.next, &imxdmac->ld_queue);
685 	cookie = dma_cookie_assign(tx);
686 	spin_unlock_irqrestore(&imxdma->lock, flags);
687 
688 	return cookie;
689 }
690 
691 static int imxdma_alloc_chan_resources(struct dma_chan *chan)
692 {
693 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
694 	struct imx_dma_data *data = chan->private;
695 
696 	if (data != NULL)
697 		imxdmac->dma_request = data->dma_request;
698 
699 	while (imxdmac->descs_allocated < IMXDMA_MAX_CHAN_DESCRIPTORS) {
700 		struct imxdma_desc *desc;
701 
702 		desc = kzalloc(sizeof(*desc), GFP_KERNEL);
703 		if (!desc)
704 			break;
705 		__memzero(&desc->desc, sizeof(struct dma_async_tx_descriptor));
706 		dma_async_tx_descriptor_init(&desc->desc, chan);
707 		desc->desc.tx_submit = imxdma_tx_submit;
708 		/* txd.flags will be overwritten in prep funcs */
709 		desc->desc.flags = DMA_CTRL_ACK;
710 		desc->status = DMA_SUCCESS;
711 
712 		list_add_tail(&desc->node, &imxdmac->ld_free);
713 		imxdmac->descs_allocated++;
714 	}
715 
716 	if (!imxdmac->descs_allocated)
717 		return -ENOMEM;
718 
719 	return imxdmac->descs_allocated;
720 }
721 
722 static void imxdma_free_chan_resources(struct dma_chan *chan)
723 {
724 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
725 	struct imxdma_engine *imxdma = imxdmac->imxdma;
726 	struct imxdma_desc *desc, *_desc;
727 	unsigned long flags;
728 
729 	spin_lock_irqsave(&imxdma->lock, flags);
730 
731 	imxdma_disable_hw(imxdmac);
732 	list_splice_tail_init(&imxdmac->ld_active, &imxdmac->ld_free);
733 	list_splice_tail_init(&imxdmac->ld_queue, &imxdmac->ld_free);
734 
735 	spin_unlock_irqrestore(&imxdma->lock, flags);
736 
737 	list_for_each_entry_safe(desc, _desc, &imxdmac->ld_free, node) {
738 		kfree(desc);
739 		imxdmac->descs_allocated--;
740 	}
741 	INIT_LIST_HEAD(&imxdmac->ld_free);
742 
743 	if (imxdmac->sg_list) {
744 		kfree(imxdmac->sg_list);
745 		imxdmac->sg_list = NULL;
746 	}
747 }
748 
749 static struct dma_async_tx_descriptor *imxdma_prep_slave_sg(
750 		struct dma_chan *chan, struct scatterlist *sgl,
751 		unsigned int sg_len, enum dma_transfer_direction direction,
752 		unsigned long flags, void *context)
753 {
754 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
755 	struct scatterlist *sg;
756 	int i, dma_length = 0;
757 	struct imxdma_desc *desc;
758 
759 	if (list_empty(&imxdmac->ld_free) ||
760 	    imxdma_chan_is_doing_cyclic(imxdmac))
761 		return NULL;
762 
763 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
764 
765 	for_each_sg(sgl, sg, sg_len, i) {
766 		dma_length += sg->length;
767 	}
768 
769 	switch (imxdmac->word_size) {
770 	case DMA_SLAVE_BUSWIDTH_4_BYTES:
771 		if (sgl->length & 3 || sgl->dma_address & 3)
772 			return NULL;
773 		break;
774 	case DMA_SLAVE_BUSWIDTH_2_BYTES:
775 		if (sgl->length & 1 || sgl->dma_address & 1)
776 			return NULL;
777 		break;
778 	case DMA_SLAVE_BUSWIDTH_1_BYTE:
779 		break;
780 	default:
781 		return NULL;
782 	}
783 
784 	desc->type = IMXDMA_DESC_SLAVE_SG;
785 	desc->sg = sgl;
786 	desc->sgcount = sg_len;
787 	desc->len = dma_length;
788 	desc->direction = direction;
789 	if (direction == DMA_DEV_TO_MEM) {
790 		desc->src = imxdmac->per_address;
791 	} else {
792 		desc->dest = imxdmac->per_address;
793 	}
794 	desc->desc.callback = NULL;
795 	desc->desc.callback_param = NULL;
796 
797 	return &desc->desc;
798 }
799 
800 static struct dma_async_tx_descriptor *imxdma_prep_dma_cyclic(
801 		struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
802 		size_t period_len, enum dma_transfer_direction direction,
803 		void *context)
804 {
805 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
806 	struct imxdma_engine *imxdma = imxdmac->imxdma;
807 	struct imxdma_desc *desc;
808 	int i;
809 	unsigned int periods = buf_len / period_len;
810 
811 	dev_dbg(imxdma->dev, "%s channel: %d buf_len=%d period_len=%d\n",
812 			__func__, imxdmac->channel, buf_len, period_len);
813 
814 	if (list_empty(&imxdmac->ld_free) ||
815 	    imxdma_chan_is_doing_cyclic(imxdmac))
816 		return NULL;
817 
818 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
819 
820 	if (imxdmac->sg_list)
821 		kfree(imxdmac->sg_list);
822 
823 	imxdmac->sg_list = kcalloc(periods + 1,
824 			sizeof(struct scatterlist), GFP_KERNEL);
825 	if (!imxdmac->sg_list)
826 		return NULL;
827 
828 	sg_init_table(imxdmac->sg_list, periods);
829 
830 	for (i = 0; i < periods; i++) {
831 		imxdmac->sg_list[i].page_link = 0;
832 		imxdmac->sg_list[i].offset = 0;
833 		imxdmac->sg_list[i].dma_address = dma_addr;
834 		imxdmac->sg_list[i].length = period_len;
835 		dma_addr += period_len;
836 	}
837 
838 	/* close the loop */
839 	imxdmac->sg_list[periods].offset = 0;
840 	imxdmac->sg_list[periods].length = 0;
841 	imxdmac->sg_list[periods].page_link =
842 		((unsigned long)imxdmac->sg_list | 0x01) & ~0x02;
843 
844 	desc->type = IMXDMA_DESC_CYCLIC;
845 	desc->sg = imxdmac->sg_list;
846 	desc->sgcount = periods;
847 	desc->len = IMX_DMA_LENGTH_LOOP;
848 	desc->direction = direction;
849 	if (direction == DMA_DEV_TO_MEM) {
850 		desc->src = imxdmac->per_address;
851 	} else {
852 		desc->dest = imxdmac->per_address;
853 	}
854 	desc->desc.callback = NULL;
855 	desc->desc.callback_param = NULL;
856 
857 	return &desc->desc;
858 }
859 
860 static struct dma_async_tx_descriptor *imxdma_prep_dma_memcpy(
861 	struct dma_chan *chan, dma_addr_t dest,
862 	dma_addr_t src, size_t len, unsigned long flags)
863 {
864 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
865 	struct imxdma_engine *imxdma = imxdmac->imxdma;
866 	struct imxdma_desc *desc;
867 
868 	dev_dbg(imxdma->dev, "%s channel: %d src=0x%x dst=0x%x len=%d\n",
869 			__func__, imxdmac->channel, src, dest, len);
870 
871 	if (list_empty(&imxdmac->ld_free) ||
872 	    imxdma_chan_is_doing_cyclic(imxdmac))
873 		return NULL;
874 
875 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
876 
877 	desc->type = IMXDMA_DESC_MEMCPY;
878 	desc->src = src;
879 	desc->dest = dest;
880 	desc->len = len;
881 	desc->direction = DMA_MEM_TO_MEM;
882 	desc->config_port = IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR;
883 	desc->config_mem = IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR;
884 	desc->desc.callback = NULL;
885 	desc->desc.callback_param = NULL;
886 
887 	return &desc->desc;
888 }
889 
890 static struct dma_async_tx_descriptor *imxdma_prep_dma_interleaved(
891 	struct dma_chan *chan, struct dma_interleaved_template *xt,
892 	unsigned long flags)
893 {
894 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
895 	struct imxdma_engine *imxdma = imxdmac->imxdma;
896 	struct imxdma_desc *desc;
897 
898 	dev_dbg(imxdma->dev, "%s channel: %d src_start=0x%x dst_start=0x%x\n"
899 		"   src_sgl=%s dst_sgl=%s numf=%d frame_size=%d\n", __func__,
900 		imxdmac->channel, xt->src_start, xt->dst_start,
901 		xt->src_sgl ? "true" : "false", xt->dst_sgl ? "true" : "false",
902 		xt->numf, xt->frame_size);
903 
904 	if (list_empty(&imxdmac->ld_free) ||
905 	    imxdma_chan_is_doing_cyclic(imxdmac))
906 		return NULL;
907 
908 	if (xt->frame_size != 1 || xt->numf <= 0 || xt->dir != DMA_MEM_TO_MEM)
909 		return NULL;
910 
911 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
912 
913 	desc->type = IMXDMA_DESC_INTERLEAVED;
914 	desc->src = xt->src_start;
915 	desc->dest = xt->dst_start;
916 	desc->x = xt->sgl[0].size;
917 	desc->y = xt->numf;
918 	desc->w = xt->sgl[0].icg + desc->x;
919 	desc->len = desc->x * desc->y;
920 	desc->direction = DMA_MEM_TO_MEM;
921 	desc->config_port = IMX_DMA_MEMSIZE_32;
922 	desc->config_mem = IMX_DMA_MEMSIZE_32;
923 	if (xt->src_sgl)
924 		desc->config_mem |= IMX_DMA_TYPE_2D;
925 	if (xt->dst_sgl)
926 		desc->config_port |= IMX_DMA_TYPE_2D;
927 	desc->desc.callback = NULL;
928 	desc->desc.callback_param = NULL;
929 
930 	return &desc->desc;
931 }
932 
933 static void imxdma_issue_pending(struct dma_chan *chan)
934 {
935 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
936 	struct imxdma_engine *imxdma = imxdmac->imxdma;
937 	struct imxdma_desc *desc;
938 	unsigned long flags;
939 
940 	spin_lock_irqsave(&imxdma->lock, flags);
941 	if (list_empty(&imxdmac->ld_active) &&
942 	    !list_empty(&imxdmac->ld_queue)) {
943 		desc = list_first_entry(&imxdmac->ld_queue,
944 					struct imxdma_desc, node);
945 
946 		if (imxdma_xfer_desc(desc) < 0) {
947 			dev_warn(imxdma->dev,
948 				 "%s: channel: %d couldn't issue DMA xfer\n",
949 				 __func__, imxdmac->channel);
950 		} else {
951 			list_move_tail(imxdmac->ld_queue.next,
952 				       &imxdmac->ld_active);
953 		}
954 	}
955 	spin_unlock_irqrestore(&imxdma->lock, flags);
956 }
957 
958 static int __init imxdma_probe(struct platform_device *pdev)
959 	{
960 	struct imxdma_engine *imxdma;
961 	int ret, i;
962 
963 
964 	imxdma = kzalloc(sizeof(*imxdma), GFP_KERNEL);
965 	if (!imxdma)
966 		return -ENOMEM;
967 
968 	if (cpu_is_mx1()) {
969 		imxdma->base = MX1_IO_ADDRESS(MX1_DMA_BASE_ADDR);
970 	} else if (cpu_is_mx21()) {
971 		imxdma->base = MX21_IO_ADDRESS(MX21_DMA_BASE_ADDR);
972 	} else if (cpu_is_mx27()) {
973 		imxdma->base = MX27_IO_ADDRESS(MX27_DMA_BASE_ADDR);
974 	} else {
975 		kfree(imxdma);
976 		return 0;
977 	}
978 
979 	imxdma->dma_clk = clk_get(NULL, "dma");
980 	if (IS_ERR(imxdma->dma_clk))
981 		return PTR_ERR(imxdma->dma_clk);
982 	clk_enable(imxdma->dma_clk);
983 
984 	/* reset DMA module */
985 	imx_dmav1_writel(imxdma, DCR_DRST, DMA_DCR);
986 
987 	if (cpu_is_mx1()) {
988 		ret = request_irq(MX1_DMA_INT, dma_irq_handler, 0, "DMA", imxdma);
989 		if (ret) {
990 			dev_warn(imxdma->dev, "Can't register IRQ for DMA\n");
991 			kfree(imxdma);
992 			return ret;
993 		}
994 
995 		ret = request_irq(MX1_DMA_ERR, imxdma_err_handler, 0, "DMA", imxdma);
996 		if (ret) {
997 			dev_warn(imxdma->dev, "Can't register ERRIRQ for DMA\n");
998 			free_irq(MX1_DMA_INT, NULL);
999 			kfree(imxdma);
1000 			return ret;
1001 		}
1002 	}
1003 
1004 	/* enable DMA module */
1005 	imx_dmav1_writel(imxdma, DCR_DEN, DMA_DCR);
1006 
1007 	/* clear all interrupts */
1008 	imx_dmav1_writel(imxdma, (1 << IMX_DMA_CHANNELS) - 1, DMA_DISR);
1009 
1010 	/* disable interrupts */
1011 	imx_dmav1_writel(imxdma, (1 << IMX_DMA_CHANNELS) - 1, DMA_DIMR);
1012 
1013 	INIT_LIST_HEAD(&imxdma->dma_device.channels);
1014 
1015 	dma_cap_set(DMA_SLAVE, imxdma->dma_device.cap_mask);
1016 	dma_cap_set(DMA_CYCLIC, imxdma->dma_device.cap_mask);
1017 	dma_cap_set(DMA_MEMCPY, imxdma->dma_device.cap_mask);
1018 	dma_cap_set(DMA_INTERLEAVE, imxdma->dma_device.cap_mask);
1019 
1020 	/* Initialize 2D global parameters */
1021 	for (i = 0; i < IMX_DMA_2D_SLOTS; i++)
1022 		imxdma->slots_2d[i].count = 0;
1023 
1024 	spin_lock_init(&imxdma->lock);
1025 
1026 	/* Initialize channel parameters */
1027 	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
1028 		struct imxdma_channel *imxdmac = &imxdma->channel[i];
1029 
1030 		if (cpu_is_mx21() || cpu_is_mx27()) {
1031 			ret = request_irq(MX2x_INT_DMACH0 + i,
1032 					dma_irq_handler, 0, "DMA", imxdma);
1033 			if (ret) {
1034 				dev_warn(imxdma->dev, "Can't register IRQ %d "
1035 					 "for DMA channel %d\n",
1036 					 MX2x_INT_DMACH0 + i, i);
1037 				goto err_init;
1038 			}
1039 			init_timer(&imxdmac->watchdog);
1040 			imxdmac->watchdog.function = &imxdma_watchdog;
1041 			imxdmac->watchdog.data = (unsigned long)imxdmac;
1042 		}
1043 
1044 		imxdmac->imxdma = imxdma;
1045 
1046 		INIT_LIST_HEAD(&imxdmac->ld_queue);
1047 		INIT_LIST_HEAD(&imxdmac->ld_free);
1048 		INIT_LIST_HEAD(&imxdmac->ld_active);
1049 
1050 		tasklet_init(&imxdmac->dma_tasklet, imxdma_tasklet,
1051 			     (unsigned long)imxdmac);
1052 		imxdmac->chan.device = &imxdma->dma_device;
1053 		dma_cookie_init(&imxdmac->chan);
1054 		imxdmac->channel = i;
1055 
1056 		/* Add the channel to the DMAC list */
1057 		list_add_tail(&imxdmac->chan.device_node,
1058 			      &imxdma->dma_device.channels);
1059 	}
1060 
1061 	imxdma->dev = &pdev->dev;
1062 	imxdma->dma_device.dev = &pdev->dev;
1063 
1064 	imxdma->dma_device.device_alloc_chan_resources = imxdma_alloc_chan_resources;
1065 	imxdma->dma_device.device_free_chan_resources = imxdma_free_chan_resources;
1066 	imxdma->dma_device.device_tx_status = imxdma_tx_status;
1067 	imxdma->dma_device.device_prep_slave_sg = imxdma_prep_slave_sg;
1068 	imxdma->dma_device.device_prep_dma_cyclic = imxdma_prep_dma_cyclic;
1069 	imxdma->dma_device.device_prep_dma_memcpy = imxdma_prep_dma_memcpy;
1070 	imxdma->dma_device.device_prep_interleaved_dma = imxdma_prep_dma_interleaved;
1071 	imxdma->dma_device.device_control = imxdma_control;
1072 	imxdma->dma_device.device_issue_pending = imxdma_issue_pending;
1073 
1074 	platform_set_drvdata(pdev, imxdma);
1075 
1076 	imxdma->dma_device.copy_align = 2; /* 2^2 = 4 bytes alignment */
1077 	imxdma->dma_device.dev->dma_parms = &imxdma->dma_parms;
1078 	dma_set_max_seg_size(imxdma->dma_device.dev, 0xffffff);
1079 
1080 	ret = dma_async_device_register(&imxdma->dma_device);
1081 	if (ret) {
1082 		dev_err(&pdev->dev, "unable to register\n");
1083 		goto err_init;
1084 	}
1085 
1086 	return 0;
1087 
1088 err_init:
1089 
1090 	if (cpu_is_mx21() || cpu_is_mx27()) {
1091 		while (--i >= 0)
1092 			free_irq(MX2x_INT_DMACH0 + i, NULL);
1093 	} else if cpu_is_mx1() {
1094 		free_irq(MX1_DMA_INT, NULL);
1095 		free_irq(MX1_DMA_ERR, NULL);
1096 	}
1097 
1098 	kfree(imxdma);
1099 	return ret;
1100 }
1101 
1102 static int __exit imxdma_remove(struct platform_device *pdev)
1103 {
1104 	struct imxdma_engine *imxdma = platform_get_drvdata(pdev);
1105 	int i;
1106 
1107         dma_async_device_unregister(&imxdma->dma_device);
1108 
1109 	if (cpu_is_mx21() || cpu_is_mx27()) {
1110 		for (i = 0; i < IMX_DMA_CHANNELS; i++)
1111 			free_irq(MX2x_INT_DMACH0 + i, NULL);
1112 	} else if cpu_is_mx1() {
1113 		free_irq(MX1_DMA_INT, NULL);
1114 		free_irq(MX1_DMA_ERR, NULL);
1115 	}
1116 
1117         kfree(imxdma);
1118 
1119         return 0;
1120 }
1121 
1122 static struct platform_driver imxdma_driver = {
1123 	.driver		= {
1124 		.name	= "imx-dma",
1125 	},
1126 	.remove		= __exit_p(imxdma_remove),
1127 };
1128 
1129 static int __init imxdma_module_init(void)
1130 {
1131 	return platform_driver_probe(&imxdma_driver, imxdma_probe);
1132 }
1133 subsys_initcall(imxdma_module_init);
1134 
1135 MODULE_AUTHOR("Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>");
1136 MODULE_DESCRIPTION("i.MX dma driver");
1137 MODULE_LICENSE("GPL");
1138