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radix tree: use GFP_ZONEMASK bits of gfp_t for flags
[linux/fpc-iii.git] / drivers / dma / dma-jz4740.c
blobafd5e10f8927cb0c5573bb946a48755aad58b0aa
1 /*
2 * Copyright (C) 2013, Lars-Peter Clausen <lars@metafoo.de>
3 * JZ4740 DMAC support
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
9 *
10 */
11
12 #include <linux/dmaengine.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/err.h>
15 #include <linux/init.h>
16 #include <linux/list.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/slab.h>
20 #include <linux/spinlock.h>
21 #include <linux/irq.h>
22 #include <linux/clk.h>
23
24 #include "virt-dma.h"
25
26 #define JZ_DMA_NR_CHANS 6
27
28 #define JZ_REG_DMA_SRC_ADDR(x) (0x00 + (x) * 0x20)
29 #define JZ_REG_DMA_DST_ADDR(x) (0x04 + (x) * 0x20)
30 #define JZ_REG_DMA_TRANSFER_COUNT(x) (0x08 + (x) * 0x20)
31 #define JZ_REG_DMA_REQ_TYPE(x) (0x0C + (x) * 0x20)
32 #define JZ_REG_DMA_STATUS_CTRL(x) (0x10 + (x) * 0x20)
33 #define JZ_REG_DMA_CMD(x) (0x14 + (x) * 0x20)
34 #define JZ_REG_DMA_DESC_ADDR(x) (0x18 + (x) * 0x20)
35
36 #define JZ_REG_DMA_CTRL 0x300
37 #define JZ_REG_DMA_IRQ 0x304
38 #define JZ_REG_DMA_DOORBELL 0x308
39 #define JZ_REG_DMA_DOORBELL_SET 0x30C
40
41 #define JZ_DMA_STATUS_CTRL_NO_DESC BIT(31)
42 #define JZ_DMA_STATUS_CTRL_DESC_INV BIT(6)
43 #define JZ_DMA_STATUS_CTRL_ADDR_ERR BIT(4)
44 #define JZ_DMA_STATUS_CTRL_TRANSFER_DONE BIT(3)
45 #define JZ_DMA_STATUS_CTRL_HALT BIT(2)
46 #define JZ_DMA_STATUS_CTRL_COUNT_TERMINATE BIT(1)
47 #define JZ_DMA_STATUS_CTRL_ENABLE BIT(0)
48
49 #define JZ_DMA_CMD_SRC_INC BIT(23)
50 #define JZ_DMA_CMD_DST_INC BIT(22)
51 #define JZ_DMA_CMD_RDIL_MASK (0xf << 16)
52 #define JZ_DMA_CMD_SRC_WIDTH_MASK (0x3 << 14)
53 #define JZ_DMA_CMD_DST_WIDTH_MASK (0x3 << 12)
54 #define JZ_DMA_CMD_INTERVAL_LENGTH_MASK (0x7 << 8)
55 #define JZ_DMA_CMD_BLOCK_MODE BIT(7)
56 #define JZ_DMA_CMD_DESC_VALID BIT(4)
57 #define JZ_DMA_CMD_DESC_VALID_MODE BIT(3)
58 #define JZ_DMA_CMD_VALID_IRQ_ENABLE BIT(2)
59 #define JZ_DMA_CMD_TRANSFER_IRQ_ENABLE BIT(1)
60 #define JZ_DMA_CMD_LINK_ENABLE BIT(0)
61
62 #define JZ_DMA_CMD_FLAGS_OFFSET 22
63 #define JZ_DMA_CMD_RDIL_OFFSET 16
64 #define JZ_DMA_CMD_SRC_WIDTH_OFFSET 14
65 #define JZ_DMA_CMD_DST_WIDTH_OFFSET 12
66 #define JZ_DMA_CMD_TRANSFER_SIZE_OFFSET 8
67 #define JZ_DMA_CMD_MODE_OFFSET 7
68
69 #define JZ_DMA_CTRL_PRIORITY_MASK (0x3 << 8)
70 #define JZ_DMA_CTRL_HALT BIT(3)
71 #define JZ_DMA_CTRL_ADDRESS_ERROR BIT(2)
72 #define JZ_DMA_CTRL_ENABLE BIT(0)
73
74 enum jz4740_dma_width {
75 JZ4740_DMA_WIDTH_32BIT = 0,
76 JZ4740_DMA_WIDTH_8BIT = 1,
77 JZ4740_DMA_WIDTH_16BIT = 2,
78 };
79
80 enum jz4740_dma_transfer_size {
81 JZ4740_DMA_TRANSFER_SIZE_4BYTE = 0,
82 JZ4740_DMA_TRANSFER_SIZE_1BYTE = 1,
83 JZ4740_DMA_TRANSFER_SIZE_2BYTE = 2,
84 JZ4740_DMA_TRANSFER_SIZE_16BYTE = 3,
85 JZ4740_DMA_TRANSFER_SIZE_32BYTE = 4,
86 };
87
88 enum jz4740_dma_flags {
89 JZ4740_DMA_SRC_AUTOINC = 0x2,
90 JZ4740_DMA_DST_AUTOINC = 0x1,
91 };
92
93 enum jz4740_dma_mode {
94 JZ4740_DMA_MODE_SINGLE = 0,
95 JZ4740_DMA_MODE_BLOCK = 1,
96 };
97
98 struct jz4740_dma_sg {
99 dma_addr_t addr;
100 unsigned int len;
101 };
102
103 struct jz4740_dma_desc {
104 struct virt_dma_desc vdesc;
105
106 enum dma_transfer_direction direction;
107 bool cyclic;
108
109 unsigned int num_sgs;
110 struct jz4740_dma_sg sg[];
111 };
112
113 struct jz4740_dmaengine_chan {
114 struct virt_dma_chan vchan;
115 unsigned int id;
116
117 dma_addr_t fifo_addr;
118 unsigned int transfer_shift;
119
120 struct jz4740_dma_desc *desc;
121 unsigned int next_sg;
122 };
123
124 struct jz4740_dma_dev {
125 struct dma_device ddev;
126 void __iomem *base;
127 struct clk *clk;
128
129 struct jz4740_dmaengine_chan chan[JZ_DMA_NR_CHANS];
130 };
131
132 static struct jz4740_dma_dev *jz4740_dma_chan_get_dev(
133 struct jz4740_dmaengine_chan *chan)
134 {
135 return container_of(chan->vchan.chan.device, struct jz4740_dma_dev,
136 ddev);
137 }
138
139 static struct jz4740_dmaengine_chan *to_jz4740_dma_chan(struct dma_chan *c)
140 {
141 return container_of(c, struct jz4740_dmaengine_chan, vchan.chan);
142 }
143
144 static struct jz4740_dma_desc *to_jz4740_dma_desc(struct virt_dma_desc *vdesc)
145 {
146 return container_of(vdesc, struct jz4740_dma_desc, vdesc);
147 }
148
149 static inline uint32_t jz4740_dma_read(struct jz4740_dma_dev *dmadev,
150 unsigned int reg)
151 {
152 return readl(dmadev->base + reg);
153 }
154
155 static inline void jz4740_dma_write(struct jz4740_dma_dev *dmadev,
156 unsigned reg, uint32_t val)
157 {
158 writel(val, dmadev->base + reg);
159 }
160
161 static inline void jz4740_dma_write_mask(struct jz4740_dma_dev *dmadev,
162 unsigned int reg, uint32_t val, uint32_t mask)
163 {
164 uint32_t tmp;
165
166 tmp = jz4740_dma_read(dmadev, reg);
167 tmp &= ~mask;
168 tmp |= val;
169 jz4740_dma_write(dmadev, reg, tmp);
170 }
171
172 static struct jz4740_dma_desc *jz4740_dma_alloc_desc(unsigned int num_sgs)
173 {
174 return kzalloc(sizeof(struct jz4740_dma_desc) +
175 sizeof(struct jz4740_dma_sg) * num_sgs, GFP_ATOMIC);
176 }
177
178 static enum jz4740_dma_width jz4740_dma_width(enum dma_slave_buswidth width)
179 {
180 switch (width) {
181 case DMA_SLAVE_BUSWIDTH_1_BYTE:
182 return JZ4740_DMA_WIDTH_8BIT;
183 case DMA_SLAVE_BUSWIDTH_2_BYTES:
184 return JZ4740_DMA_WIDTH_16BIT;
185 case DMA_SLAVE_BUSWIDTH_4_BYTES:
186 return JZ4740_DMA_WIDTH_32BIT;
187 default:
188 return JZ4740_DMA_WIDTH_32BIT;
189 }
190 }
191
192 static enum jz4740_dma_transfer_size jz4740_dma_maxburst(u32 maxburst)
193 {
194 if (maxburst <= 1)
195 return JZ4740_DMA_TRANSFER_SIZE_1BYTE;
196 else if (maxburst <= 3)
197 return JZ4740_DMA_TRANSFER_SIZE_2BYTE;
198 else if (maxburst <= 15)
199 return JZ4740_DMA_TRANSFER_SIZE_4BYTE;
200 else if (maxburst <= 31)
201 return JZ4740_DMA_TRANSFER_SIZE_16BYTE;
202
203 return JZ4740_DMA_TRANSFER_SIZE_32BYTE;
204 }
205
206 static int jz4740_dma_slave_config(struct dma_chan *c,
207 struct dma_slave_config *config)
208 {
209 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
210 struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
211 enum jz4740_dma_width src_width;
212 enum jz4740_dma_width dst_width;
213 enum jz4740_dma_transfer_size transfer_size;
214 enum jz4740_dma_flags flags;
215 uint32_t cmd;
216
217 switch (config->direction) {
218 case DMA_MEM_TO_DEV:
219 flags = JZ4740_DMA_SRC_AUTOINC;
220 transfer_size = jz4740_dma_maxburst(config->dst_maxburst);
221 chan->fifo_addr = config->dst_addr;
222 break;
223 case DMA_DEV_TO_MEM:
224 flags = JZ4740_DMA_DST_AUTOINC;
225 transfer_size = jz4740_dma_maxburst(config->src_maxburst);
226 chan->fifo_addr = config->src_addr;
227 break;
228 default:
229 return -EINVAL;
230 }
231
232 src_width = jz4740_dma_width(config->src_addr_width);
233 dst_width = jz4740_dma_width(config->dst_addr_width);
234
235 switch (transfer_size) {
236 case JZ4740_DMA_TRANSFER_SIZE_2BYTE:
237 chan->transfer_shift = 1;
238 break;
239 case JZ4740_DMA_TRANSFER_SIZE_4BYTE:
240 chan->transfer_shift = 2;
241 break;
242 case JZ4740_DMA_TRANSFER_SIZE_16BYTE:
243 chan->transfer_shift = 4;
244 break;
245 case JZ4740_DMA_TRANSFER_SIZE_32BYTE:
246 chan->transfer_shift = 5;
247 break;
248 default:
249 chan->transfer_shift = 0;
250 break;
251 }
252
253 cmd = flags << JZ_DMA_CMD_FLAGS_OFFSET;
254 cmd |= src_width << JZ_DMA_CMD_SRC_WIDTH_OFFSET;
255 cmd |= dst_width << JZ_DMA_CMD_DST_WIDTH_OFFSET;
256 cmd |= transfer_size << JZ_DMA_CMD_TRANSFER_SIZE_OFFSET;
257 cmd |= JZ4740_DMA_MODE_SINGLE << JZ_DMA_CMD_MODE_OFFSET;
258 cmd |= JZ_DMA_CMD_TRANSFER_IRQ_ENABLE;
259
260 jz4740_dma_write(dmadev, JZ_REG_DMA_CMD(chan->id), cmd);
261 jz4740_dma_write(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id), 0);
262 jz4740_dma_write(dmadev, JZ_REG_DMA_REQ_TYPE(chan->id),
263 config->slave_id);
264
265 return 0;
266 }
267
268 static int jz4740_dma_terminate_all(struct dma_chan *c)
269 {
270 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
271 struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
272 unsigned long flags;
273 LIST_HEAD(head);
274
275 spin_lock_irqsave(&chan->vchan.lock, flags);
276 jz4740_dma_write_mask(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id), 0,
277 JZ_DMA_STATUS_CTRL_ENABLE);
278 chan->desc = NULL;
279 vchan_get_all_descriptors(&chan->vchan, &head);
280 spin_unlock_irqrestore(&chan->vchan.lock, flags);
281
282 vchan_dma_desc_free_list(&chan->vchan, &head);
283
284 return 0;
285 }
286
287 static int jz4740_dma_start_transfer(struct jz4740_dmaengine_chan *chan)
288 {
289 struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
290 dma_addr_t src_addr, dst_addr;
291 struct virt_dma_desc *vdesc;
292 struct jz4740_dma_sg *sg;
293
294 jz4740_dma_write_mask(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id), 0,
295 JZ_DMA_STATUS_CTRL_ENABLE);
296
297 if (!chan->desc) {
298 vdesc = vchan_next_desc(&chan->vchan);
299 if (!vdesc)
300 return 0;
301 chan->desc = to_jz4740_dma_desc(vdesc);
302 chan->next_sg = 0;
303 }
304
305 if (chan->next_sg == chan->desc->num_sgs)
306 chan->next_sg = 0;
307
308 sg = &chan->desc->sg[chan->next_sg];
309
310 if (chan->desc->direction == DMA_MEM_TO_DEV) {
311 src_addr = sg->addr;
312 dst_addr = chan->fifo_addr;
313 } else {
314 src_addr = chan->fifo_addr;
315 dst_addr = sg->addr;
316 }
317 jz4740_dma_write(dmadev, JZ_REG_DMA_SRC_ADDR(chan->id), src_addr);
318 jz4740_dma_write(dmadev, JZ_REG_DMA_DST_ADDR(chan->id), dst_addr);
319 jz4740_dma_write(dmadev, JZ_REG_DMA_TRANSFER_COUNT(chan->id),
320 sg->len >> chan->transfer_shift);
321
322 chan->next_sg++;
323
324 jz4740_dma_write_mask(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id),
325 JZ_DMA_STATUS_CTRL_NO_DESC | JZ_DMA_STATUS_CTRL_ENABLE,
326 JZ_DMA_STATUS_CTRL_HALT | JZ_DMA_STATUS_CTRL_NO_DESC |
327 JZ_DMA_STATUS_CTRL_ENABLE);
328
329 jz4740_dma_write_mask(dmadev, JZ_REG_DMA_CTRL,
330 JZ_DMA_CTRL_ENABLE,
331 JZ_DMA_CTRL_HALT | JZ_DMA_CTRL_ENABLE);
332
333 return 0;
334 }
335
336 static void jz4740_dma_chan_irq(struct jz4740_dmaengine_chan *chan)
337 {
338 spin_lock(&chan->vchan.lock);
339 if (chan->desc) {
340 if (chan->desc->cyclic) {
341 vchan_cyclic_callback(&chan->desc->vdesc);
342 } else {
343 if (chan->next_sg == chan->desc->num_sgs) {
344 list_del(&chan->desc->vdesc.node);
345 vchan_cookie_complete(&chan->desc->vdesc);
346 chan->desc = NULL;
347 }
348 }
349 }
350 jz4740_dma_start_transfer(chan);
351 spin_unlock(&chan->vchan.lock);
352 }
353
354 static irqreturn_t jz4740_dma_irq(int irq, void *devid)
355 {
356 struct jz4740_dma_dev *dmadev = devid;
357 uint32_t irq_status;
358 unsigned int i;
359
360 irq_status = readl(dmadev->base + JZ_REG_DMA_IRQ);
361
362 for (i = 0; i < 6; ++i) {
363 if (irq_status & (1 << i)) {
364 jz4740_dma_write_mask(dmadev,
365 JZ_REG_DMA_STATUS_CTRL(i), 0,
366 JZ_DMA_STATUS_CTRL_ENABLE |
367 JZ_DMA_STATUS_CTRL_TRANSFER_DONE);
368
369 jz4740_dma_chan_irq(&dmadev->chan[i]);
370 }
371 }
372
373 return IRQ_HANDLED;
374 }
375
376 static void jz4740_dma_issue_pending(struct dma_chan *c)
377 {
378 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
379 unsigned long flags;
380
381 spin_lock_irqsave(&chan->vchan.lock, flags);
382 if (vchan_issue_pending(&chan->vchan) && !chan->desc)
383 jz4740_dma_start_transfer(chan);
384 spin_unlock_irqrestore(&chan->vchan.lock, flags);
385 }
386
387 static struct dma_async_tx_descriptor *jz4740_dma_prep_slave_sg(
388 struct dma_chan *c, struct scatterlist *sgl,
389 unsigned int sg_len, enum dma_transfer_direction direction,
390 unsigned long flags, void *context)
391 {
392 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
393 struct jz4740_dma_desc *desc;
394 struct scatterlist *sg;
395 unsigned int i;
396
397 desc = jz4740_dma_alloc_desc(sg_len);
398 if (!desc)
399 return NULL;
400
401 for_each_sg(sgl, sg, sg_len, i) {
402 desc->sg[i].addr = sg_dma_address(sg);
403 desc->sg[i].len = sg_dma_len(sg);
404 }
405
406 desc->num_sgs = sg_len;
407 desc->direction = direction;
408 desc->cyclic = false;
409
410 return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
411 }
412
413 static struct dma_async_tx_descriptor *jz4740_dma_prep_dma_cyclic(
414 struct dma_chan *c, dma_addr_t buf_addr, size_t buf_len,
415 size_t period_len, enum dma_transfer_direction direction,
416 unsigned long flags)
417 {
418 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
419 struct jz4740_dma_desc *desc;
420 unsigned int num_periods, i;
421
422 if (buf_len % period_len)
423 return NULL;
424
425 num_periods = buf_len / period_len;
426
427 desc = jz4740_dma_alloc_desc(num_periods);
428 if (!desc)
429 return NULL;
430
431 for (i = 0; i < num_periods; i++) {
432 desc->sg[i].addr = buf_addr;
433 desc->sg[i].len = period_len;
434 buf_addr += period_len;
435 }
436
437 desc->num_sgs = num_periods;
438 desc->direction = direction;
439 desc->cyclic = true;
440
441 return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
442 }
443
444 static size_t jz4740_dma_desc_residue(struct jz4740_dmaengine_chan *chan,
445 struct jz4740_dma_desc *desc, unsigned int next_sg)
446 {
447 struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
448 unsigned int residue, count;
449 unsigned int i;
450
451 residue = 0;
452
453 for (i = next_sg; i < desc->num_sgs; i++)
454 residue += desc->sg[i].len;
455
456 if (next_sg != 0) {
457 count = jz4740_dma_read(dmadev,
458 JZ_REG_DMA_TRANSFER_COUNT(chan->id));
459 residue += count << chan->transfer_shift;
460 }
461
462 return residue;
463 }
464
465 static enum dma_status jz4740_dma_tx_status(struct dma_chan *c,
466 dma_cookie_t cookie, struct dma_tx_state *state)
467 {
468 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
469 struct virt_dma_desc *vdesc;
470 enum dma_status status;
471 unsigned long flags;
472
473 status = dma_cookie_status(c, cookie, state);
474 if (status == DMA_COMPLETE || !state)
475 return status;
476
477 spin_lock_irqsave(&chan->vchan.lock, flags);
478 vdesc = vchan_find_desc(&chan->vchan, cookie);
479 if (cookie == chan->desc->vdesc.tx.cookie) {
480 state->residue = jz4740_dma_desc_residue(chan, chan->desc,
481 chan->next_sg);
482 } else if (vdesc) {
483 state->residue = jz4740_dma_desc_residue(chan,
484 to_jz4740_dma_desc(vdesc), 0);
485 } else {
486 state->residue = 0;
487 }
488 spin_unlock_irqrestore(&chan->vchan.lock, flags);
489
490 return status;
491 }
492
493 static void jz4740_dma_free_chan_resources(struct dma_chan *c)
494 {
495 vchan_free_chan_resources(to_virt_chan(c));
496 }
497
498 static void jz4740_dma_desc_free(struct virt_dma_desc *vdesc)
499 {
500 kfree(container_of(vdesc, struct jz4740_dma_desc, vdesc));
501 }
502
503 #define JZ4740_DMA_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
504 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | BIT(DMA_SLAVE_BUSWIDTH_4_BYTES))
505
506 static int jz4740_dma_probe(struct platform_device *pdev)
507 {
508 struct jz4740_dmaengine_chan *chan;
509 struct jz4740_dma_dev *dmadev;
510 struct dma_device *dd;
511 unsigned int i;
512 struct resource *res;
513 int ret;
514 int irq;
515
516 dmadev = devm_kzalloc(&pdev->dev, sizeof(*dmadev), GFP_KERNEL);
517 if (!dmadev)
518 return -EINVAL;
519
520 dd = &dmadev->ddev;
521
522 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
523 dmadev->base = devm_ioremap_resource(&pdev->dev, res);
524 if (IS_ERR(dmadev->base))
525 return PTR_ERR(dmadev->base);
526
527 dmadev->clk = clk_get(&pdev->dev, "dma");
528 if (IS_ERR(dmadev->clk))
529 return PTR_ERR(dmadev->clk);
530
531 clk_prepare_enable(dmadev->clk);
532
533 dma_cap_set(DMA_SLAVE, dd->cap_mask);
534 dma_cap_set(DMA_CYCLIC, dd->cap_mask);
535 dd->device_free_chan_resources = jz4740_dma_free_chan_resources;
536 dd->device_tx_status = jz4740_dma_tx_status;
537 dd->device_issue_pending = jz4740_dma_issue_pending;
538 dd->device_prep_slave_sg = jz4740_dma_prep_slave_sg;
539 dd->device_prep_dma_cyclic = jz4740_dma_prep_dma_cyclic;
540 dd->device_config = jz4740_dma_slave_config;
541 dd->device_terminate_all = jz4740_dma_terminate_all;
542 dd->src_addr_widths = JZ4740_DMA_BUSWIDTHS;
543 dd->dst_addr_widths = JZ4740_DMA_BUSWIDTHS;
544 dd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
545 dd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
546 dd->dev = &pdev->dev;
547 INIT_LIST_HEAD(&dd->channels);
548
549 for (i = 0; i < JZ_DMA_NR_CHANS; i++) {
550 chan = &dmadev->chan[i];
551 chan->id = i;
552 chan->vchan.desc_free = jz4740_dma_desc_free;
553 vchan_init(&chan->vchan, dd);
554 }
555
556 ret = dma_async_device_register(dd);
557 if (ret)
558 goto err_clk;
559
560 irq = platform_get_irq(pdev, 0);
561 ret = request_irq(irq, jz4740_dma_irq, 0, dev_name(&pdev->dev), dmadev);
562 if (ret)
563 goto err_unregister;
564
565 platform_set_drvdata(pdev, dmadev);
566
567 return 0;
568
569 err_unregister:
570 dma_async_device_unregister(dd);
571 err_clk:
572 clk_disable_unprepare(dmadev->clk);
573 return ret;
574 }
575
576 static void jz4740_cleanup_vchan(struct dma_device *dmadev)
577 {
578 struct jz4740_dmaengine_chan *chan, *_chan;
579
580 list_for_each_entry_safe(chan, _chan,
581 &dmadev->channels, vchan.chan.device_node) {
582 list_del(&chan->vchan.chan.device_node);
583 tasklet_kill(&chan->vchan.task);
584 }
585 }
586
587
588 static int jz4740_dma_remove(struct platform_device *pdev)
589 {
590 struct jz4740_dma_dev *dmadev = platform_get_drvdata(pdev);
591 int irq = platform_get_irq(pdev, 0);
592
593 free_irq(irq, dmadev);
594
595 jz4740_cleanup_vchan(&dmadev->ddev);
596 dma_async_device_unregister(&dmadev->ddev);
597 clk_disable_unprepare(dmadev->clk);
598
599 return 0;
600 }
601
602 static struct platform_driver jz4740_dma_driver = {
603 .probe = jz4740_dma_probe,
604 .remove = jz4740_dma_remove,
605 .driver = {
606 .name = "jz4740-dma",
607 },
608 };
609 module_platform_driver(jz4740_dma_driver);
610
611 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
612 MODULE_DESCRIPTION("JZ4740 DMA driver");
613 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support