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 * You should have received a copy of the GNU General Public License along
11 * with this program; if not, write to the Free Software Foundation, Inc.,
12 * 675 Mass Ave, Cambridge, MA 02139, USA.
13 *
14 */
15
16 #include <linux/dmaengine.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/err.h>
19 #include <linux/init.h>
20 #include <linux/list.h>
21 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 #include <linux/slab.h>
24 #include <linux/spinlock.h>
25 #include <linux/irq.h>
26 #include <linux/clk.h>
27
28 #include <asm/mach-jz4740/dma.h>
29
30 #include "virt-dma.h"
31
32 #define JZ_DMA_NR_CHANS 6
33
34 #define JZ_REG_DMA_SRC_ADDR(x) (0x00 + (x) * 0x20)
35 #define JZ_REG_DMA_DST_ADDR(x) (0x04 + (x) * 0x20)
36 #define JZ_REG_DMA_TRANSFER_COUNT(x) (0x08 + (x) * 0x20)
37 #define JZ_REG_DMA_REQ_TYPE(x) (0x0C + (x) * 0x20)
38 #define JZ_REG_DMA_STATUS_CTRL(x) (0x10 + (x) * 0x20)
39 #define JZ_REG_DMA_CMD(x) (0x14 + (x) * 0x20)
40 #define JZ_REG_DMA_DESC_ADDR(x) (0x18 + (x) * 0x20)
41
42 #define JZ_REG_DMA_CTRL 0x300
43 #define JZ_REG_DMA_IRQ 0x304
44 #define JZ_REG_DMA_DOORBELL 0x308
45 #define JZ_REG_DMA_DOORBELL_SET 0x30C
46
47 #define JZ_DMA_STATUS_CTRL_NO_DESC BIT(31)
48 #define JZ_DMA_STATUS_CTRL_DESC_INV BIT(6)
49 #define JZ_DMA_STATUS_CTRL_ADDR_ERR BIT(4)
50 #define JZ_DMA_STATUS_CTRL_TRANSFER_DONE BIT(3)
51 #define JZ_DMA_STATUS_CTRL_HALT BIT(2)
52 #define JZ_DMA_STATUS_CTRL_COUNT_TERMINATE BIT(1)
53 #define JZ_DMA_STATUS_CTRL_ENABLE BIT(0)
54
55 #define JZ_DMA_CMD_SRC_INC BIT(23)
56 #define JZ_DMA_CMD_DST_INC BIT(22)
57 #define JZ_DMA_CMD_RDIL_MASK (0xf << 16)
58 #define JZ_DMA_CMD_SRC_WIDTH_MASK (0x3 << 14)
59 #define JZ_DMA_CMD_DST_WIDTH_MASK (0x3 << 12)
60 #define JZ_DMA_CMD_INTERVAL_LENGTH_MASK (0x7 << 8)
61 #define JZ_DMA_CMD_BLOCK_MODE BIT(7)
62 #define JZ_DMA_CMD_DESC_VALID BIT(4)
63 #define JZ_DMA_CMD_DESC_VALID_MODE BIT(3)
64 #define JZ_DMA_CMD_VALID_IRQ_ENABLE BIT(2)
65 #define JZ_DMA_CMD_TRANSFER_IRQ_ENABLE BIT(1)
66 #define JZ_DMA_CMD_LINK_ENABLE BIT(0)
67
68 #define JZ_DMA_CMD_FLAGS_OFFSET 22
69 #define JZ_DMA_CMD_RDIL_OFFSET 16
70 #define JZ_DMA_CMD_SRC_WIDTH_OFFSET 14
71 #define JZ_DMA_CMD_DST_WIDTH_OFFSET 12
72 #define JZ_DMA_CMD_TRANSFER_SIZE_OFFSET 8
73 #define JZ_DMA_CMD_MODE_OFFSET 7
74
75 #define JZ_DMA_CTRL_PRIORITY_MASK (0x3 << 8)
76 #define JZ_DMA_CTRL_HALT BIT(3)
77 #define JZ_DMA_CTRL_ADDRESS_ERROR BIT(2)
78 #define JZ_DMA_CTRL_ENABLE BIT(0)
79
80 enum jz4740_dma_width {
81 JZ4740_DMA_WIDTH_32BIT = 0,
82 JZ4740_DMA_WIDTH_8BIT = 1,
83 JZ4740_DMA_WIDTH_16BIT = 2,
84 };
85
86 enum jz4740_dma_transfer_size {
87 JZ4740_DMA_TRANSFER_SIZE_4BYTE = 0,
88 JZ4740_DMA_TRANSFER_SIZE_1BYTE = 1,
89 JZ4740_DMA_TRANSFER_SIZE_2BYTE = 2,
90 JZ4740_DMA_TRANSFER_SIZE_16BYTE = 3,
91 JZ4740_DMA_TRANSFER_SIZE_32BYTE = 4,
92 };
93
94 enum jz4740_dma_flags {
95 JZ4740_DMA_SRC_AUTOINC = 0x2,
96 JZ4740_DMA_DST_AUTOINC = 0x1,
97 };
98
99 enum jz4740_dma_mode {
100 JZ4740_DMA_MODE_SINGLE = 0,
101 JZ4740_DMA_MODE_BLOCK = 1,
102 };
103
104 struct jz4740_dma_sg {
105 dma_addr_t addr;
106 unsigned int len;
107 };
108
109 struct jz4740_dma_desc {
110 struct virt_dma_desc vdesc;
111
112 enum dma_transfer_direction direction;
113 bool cyclic;
114
115 unsigned int num_sgs;
116 struct jz4740_dma_sg sg[];
117 };
118
119 struct jz4740_dmaengine_chan {
120 struct virt_dma_chan vchan;
121 unsigned int id;
122
123 dma_addr_t fifo_addr;
124 unsigned int transfer_shift;
125
126 struct jz4740_dma_desc *desc;
127 unsigned int next_sg;
128 };
129
130 struct jz4740_dma_dev {
131 struct dma_device ddev;
132 void __iomem *base;
133 struct clk *clk;
134
135 struct jz4740_dmaengine_chan chan[JZ_DMA_NR_CHANS];
136 };
137
jz4740_dma_chan_get_dev(struct jz4740_dmaengine_chan * chan)138 static struct jz4740_dma_dev *jz4740_dma_chan_get_dev(
139 struct jz4740_dmaengine_chan *chan)
140 {
141 return container_of(chan->vchan.chan.device, struct jz4740_dma_dev,
142 ddev);
143 }
144
to_jz4740_dma_chan(struct dma_chan * c)145 static struct jz4740_dmaengine_chan *to_jz4740_dma_chan(struct dma_chan *c)
146 {
147 return container_of(c, struct jz4740_dmaengine_chan, vchan.chan);
148 }
149
to_jz4740_dma_desc(struct virt_dma_desc * vdesc)150 static struct jz4740_dma_desc *to_jz4740_dma_desc(struct virt_dma_desc *vdesc)
151 {
152 return container_of(vdesc, struct jz4740_dma_desc, vdesc);
153 }
154
jz4740_dma_read(struct jz4740_dma_dev * dmadev,unsigned int reg)155 static inline uint32_t jz4740_dma_read(struct jz4740_dma_dev *dmadev,
156 unsigned int reg)
157 {
158 return readl(dmadev->base + reg);
159 }
160
jz4740_dma_write(struct jz4740_dma_dev * dmadev,unsigned reg,uint32_t val)161 static inline void jz4740_dma_write(struct jz4740_dma_dev *dmadev,
162 unsigned reg, uint32_t val)
163 {
164 writel(val, dmadev->base + reg);
165 }
166
jz4740_dma_write_mask(struct jz4740_dma_dev * dmadev,unsigned int reg,uint32_t val,uint32_t mask)167 static inline void jz4740_dma_write_mask(struct jz4740_dma_dev *dmadev,
168 unsigned int reg, uint32_t val, uint32_t mask)
169 {
170 uint32_t tmp;
171
172 tmp = jz4740_dma_read(dmadev, reg);
173 tmp &= ~mask;
174 tmp |= val;
175 jz4740_dma_write(dmadev, reg, tmp);
176 }
177
jz4740_dma_alloc_desc(unsigned int num_sgs)178 static struct jz4740_dma_desc *jz4740_dma_alloc_desc(unsigned int num_sgs)
179 {
180 return kzalloc(sizeof(struct jz4740_dma_desc) +
181 sizeof(struct jz4740_dma_sg) * num_sgs, GFP_ATOMIC);
182 }
183
jz4740_dma_width(enum dma_slave_buswidth width)184 static enum jz4740_dma_width jz4740_dma_width(enum dma_slave_buswidth width)
185 {
186 switch (width) {
187 case DMA_SLAVE_BUSWIDTH_1_BYTE:
188 return JZ4740_DMA_WIDTH_8BIT;
189 case DMA_SLAVE_BUSWIDTH_2_BYTES:
190 return JZ4740_DMA_WIDTH_16BIT;
191 case DMA_SLAVE_BUSWIDTH_4_BYTES:
192 return JZ4740_DMA_WIDTH_32BIT;
193 default:
194 return JZ4740_DMA_WIDTH_32BIT;
195 }
196 }
197
jz4740_dma_maxburst(u32 maxburst)198 static enum jz4740_dma_transfer_size jz4740_dma_maxburst(u32 maxburst)
199 {
200 if (maxburst <= 1)
201 return JZ4740_DMA_TRANSFER_SIZE_1BYTE;
202 else if (maxburst <= 3)
203 return JZ4740_DMA_TRANSFER_SIZE_2BYTE;
204 else if (maxburst <= 15)
205 return JZ4740_DMA_TRANSFER_SIZE_4BYTE;
206 else if (maxburst <= 31)
207 return JZ4740_DMA_TRANSFER_SIZE_16BYTE;
208
209 return JZ4740_DMA_TRANSFER_SIZE_32BYTE;
210 }
211
jz4740_dma_slave_config(struct dma_chan * c,const struct dma_slave_config * config)212 static int jz4740_dma_slave_config(struct dma_chan *c,
213 const struct dma_slave_config *config)
214 {
215 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
216 struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
217 enum jz4740_dma_width src_width;
218 enum jz4740_dma_width dst_width;
219 enum jz4740_dma_transfer_size transfer_size;
220 enum jz4740_dma_flags flags;
221 uint32_t cmd;
222
223 switch (config->direction) {
224 case DMA_MEM_TO_DEV:
225 flags = JZ4740_DMA_SRC_AUTOINC;
226 transfer_size = jz4740_dma_maxburst(config->dst_maxburst);
227 chan->fifo_addr = config->dst_addr;
228 break;
229 case DMA_DEV_TO_MEM:
230 flags = JZ4740_DMA_DST_AUTOINC;
231 transfer_size = jz4740_dma_maxburst(config->src_maxburst);
232 chan->fifo_addr = config->src_addr;
233 break;
234 default:
235 return -EINVAL;
236 }
237
238 src_width = jz4740_dma_width(config->src_addr_width);
239 dst_width = jz4740_dma_width(config->dst_addr_width);
240
241 switch (transfer_size) {
242 case JZ4740_DMA_TRANSFER_SIZE_2BYTE:
243 chan->transfer_shift = 1;
244 break;
245 case JZ4740_DMA_TRANSFER_SIZE_4BYTE:
246 chan->transfer_shift = 2;
247 break;
248 case JZ4740_DMA_TRANSFER_SIZE_16BYTE:
249 chan->transfer_shift = 4;
250 break;
251 case JZ4740_DMA_TRANSFER_SIZE_32BYTE:
252 chan->transfer_shift = 5;
253 break;
254 default:
255 chan->transfer_shift = 0;
256 break;
257 }
258
259 cmd = flags << JZ_DMA_CMD_FLAGS_OFFSET;
260 cmd |= src_width << JZ_DMA_CMD_SRC_WIDTH_OFFSET;
261 cmd |= dst_width << JZ_DMA_CMD_DST_WIDTH_OFFSET;
262 cmd |= transfer_size << JZ_DMA_CMD_TRANSFER_SIZE_OFFSET;
263 cmd |= JZ4740_DMA_MODE_SINGLE << JZ_DMA_CMD_MODE_OFFSET;
264 cmd |= JZ_DMA_CMD_TRANSFER_IRQ_ENABLE;
265
266 jz4740_dma_write(dmadev, JZ_REG_DMA_CMD(chan->id), cmd);
267 jz4740_dma_write(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id), 0);
268 jz4740_dma_write(dmadev, JZ_REG_DMA_REQ_TYPE(chan->id),
269 config->slave_id);
270
271 return 0;
272 }
273
jz4740_dma_terminate_all(struct dma_chan * c)274 static int jz4740_dma_terminate_all(struct dma_chan *c)
275 {
276 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
277 struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
278 unsigned long flags;
279 LIST_HEAD(head);
280
281 spin_lock_irqsave(&chan->vchan.lock, flags);
282 jz4740_dma_write_mask(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id), 0,
283 JZ_DMA_STATUS_CTRL_ENABLE);
284 chan->desc = NULL;
285 vchan_get_all_descriptors(&chan->vchan, &head);
286 spin_unlock_irqrestore(&chan->vchan.lock, flags);
287
288 vchan_dma_desc_free_list(&chan->vchan, &head);
289
290 return 0;
291 }
292
jz4740_dma_control(struct dma_chan * chan,enum dma_ctrl_cmd cmd,unsigned long arg)293 static int jz4740_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
294 unsigned long arg)
295 {
296 struct dma_slave_config *config = (struct dma_slave_config *)arg;
297
298 switch (cmd) {
299 case DMA_SLAVE_CONFIG:
300 return jz4740_dma_slave_config(chan, config);
301 case DMA_TERMINATE_ALL:
302 return jz4740_dma_terminate_all(chan);
303 default:
304 return -ENOSYS;
305 }
306 }
307
jz4740_dma_start_transfer(struct jz4740_dmaengine_chan * chan)308 static int jz4740_dma_start_transfer(struct jz4740_dmaengine_chan *chan)
309 {
310 struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
311 dma_addr_t src_addr, dst_addr;
312 struct virt_dma_desc *vdesc;
313 struct jz4740_dma_sg *sg;
314
315 jz4740_dma_write_mask(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id), 0,
316 JZ_DMA_STATUS_CTRL_ENABLE);
317
318 if (!chan->desc) {
319 vdesc = vchan_next_desc(&chan->vchan);
320 if (!vdesc)
321 return 0;
322 chan->desc = to_jz4740_dma_desc(vdesc);
323 chan->next_sg = 0;
324 }
325
326 if (chan->next_sg == chan->desc->num_sgs)
327 chan->next_sg = 0;
328
329 sg = &chan->desc->sg[chan->next_sg];
330
331 if (chan->desc->direction == DMA_MEM_TO_DEV) {
332 src_addr = sg->addr;
333 dst_addr = chan->fifo_addr;
334 } else {
335 src_addr = chan->fifo_addr;
336 dst_addr = sg->addr;
337 }
338 jz4740_dma_write(dmadev, JZ_REG_DMA_SRC_ADDR(chan->id), src_addr);
339 jz4740_dma_write(dmadev, JZ_REG_DMA_DST_ADDR(chan->id), dst_addr);
340 jz4740_dma_write(dmadev, JZ_REG_DMA_TRANSFER_COUNT(chan->id),
341 sg->len >> chan->transfer_shift);
342
343 chan->next_sg++;
344
345 jz4740_dma_write_mask(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id),
346 JZ_DMA_STATUS_CTRL_NO_DESC | JZ_DMA_STATUS_CTRL_ENABLE,
347 JZ_DMA_STATUS_CTRL_HALT | JZ_DMA_STATUS_CTRL_NO_DESC |
348 JZ_DMA_STATUS_CTRL_ENABLE);
349
350 jz4740_dma_write_mask(dmadev, JZ_REG_DMA_CTRL,
351 JZ_DMA_CTRL_ENABLE,
352 JZ_DMA_CTRL_HALT | JZ_DMA_CTRL_ENABLE);
353
354 return 0;
355 }
356
jz4740_dma_chan_irq(struct jz4740_dmaengine_chan * chan)357 static void jz4740_dma_chan_irq(struct jz4740_dmaengine_chan *chan)
358 {
359 spin_lock(&chan->vchan.lock);
360 if (chan->desc) {
361 if (chan->desc && chan->desc->cyclic) {
362 vchan_cyclic_callback(&chan->desc->vdesc);
363 } else {
364 if (chan->next_sg == chan->desc->num_sgs) {
365 list_del(&chan->desc->vdesc.node);
366 vchan_cookie_complete(&chan->desc->vdesc);
367 chan->desc = NULL;
368 }
369 }
370 }
371 jz4740_dma_start_transfer(chan);
372 spin_unlock(&chan->vchan.lock);
373 }
374
jz4740_dma_irq(int irq,void * devid)375 static irqreturn_t jz4740_dma_irq(int irq, void *devid)
376 {
377 struct jz4740_dma_dev *dmadev = devid;
378 uint32_t irq_status;
379 unsigned int i;
380
381 irq_status = readl(dmadev->base + JZ_REG_DMA_IRQ);
382
383 for (i = 0; i < 6; ++i) {
384 if (irq_status & (1 << i)) {
385 jz4740_dma_write_mask(dmadev,
386 JZ_REG_DMA_STATUS_CTRL(i), 0,
387 JZ_DMA_STATUS_CTRL_ENABLE |
388 JZ_DMA_STATUS_CTRL_TRANSFER_DONE);
389
390 jz4740_dma_chan_irq(&dmadev->chan[i]);
391 }
392 }
393
394 return IRQ_HANDLED;
395 }
396
jz4740_dma_issue_pending(struct dma_chan * c)397 static void jz4740_dma_issue_pending(struct dma_chan *c)
398 {
399 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
400 unsigned long flags;
401
402 spin_lock_irqsave(&chan->vchan.lock, flags);
403 if (vchan_issue_pending(&chan->vchan) && !chan->desc)
404 jz4740_dma_start_transfer(chan);
405 spin_unlock_irqrestore(&chan->vchan.lock, flags);
406 }
407
jz4740_dma_prep_slave_sg(struct dma_chan * c,struct scatterlist * sgl,unsigned int sg_len,enum dma_transfer_direction direction,unsigned long flags,void * context)408 static struct dma_async_tx_descriptor *jz4740_dma_prep_slave_sg(
409 struct dma_chan *c, struct scatterlist *sgl,
410 unsigned int sg_len, enum dma_transfer_direction direction,
411 unsigned long flags, void *context)
412 {
413 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
414 struct jz4740_dma_desc *desc;
415 struct scatterlist *sg;
416 unsigned int i;
417
418 desc = jz4740_dma_alloc_desc(sg_len);
419 if (!desc)
420 return NULL;
421
422 for_each_sg(sgl, sg, sg_len, i) {
423 desc->sg[i].addr = sg_dma_address(sg);
424 desc->sg[i].len = sg_dma_len(sg);
425 }
426
427 desc->num_sgs = sg_len;
428 desc->direction = direction;
429 desc->cyclic = false;
430
431 return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
432 }
433
jz4740_dma_prep_dma_cyclic(struct dma_chan * c,dma_addr_t buf_addr,size_t buf_len,size_t period_len,enum dma_transfer_direction direction,unsigned long flags)434 static struct dma_async_tx_descriptor *jz4740_dma_prep_dma_cyclic(
435 struct dma_chan *c, dma_addr_t buf_addr, size_t buf_len,
436 size_t period_len, enum dma_transfer_direction direction,
437 unsigned long flags)
438 {
439 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
440 struct jz4740_dma_desc *desc;
441 unsigned int num_periods, i;
442
443 if (buf_len % period_len)
444 return NULL;
445
446 num_periods = buf_len / period_len;
447
448 desc = jz4740_dma_alloc_desc(num_periods);
449 if (!desc)
450 return NULL;
451
452 for (i = 0; i < num_periods; i++) {
453 desc->sg[i].addr = buf_addr;
454 desc->sg[i].len = period_len;
455 buf_addr += period_len;
456 }
457
458 desc->num_sgs = num_periods;
459 desc->direction = direction;
460 desc->cyclic = true;
461
462 return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
463 }
464
jz4740_dma_desc_residue(struct jz4740_dmaengine_chan * chan,struct jz4740_dma_desc * desc,unsigned int next_sg)465 static size_t jz4740_dma_desc_residue(struct jz4740_dmaengine_chan *chan,
466 struct jz4740_dma_desc *desc, unsigned int next_sg)
467 {
468 struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
469 unsigned int residue, count;
470 unsigned int i;
471
472 residue = 0;
473
474 for (i = next_sg; i < desc->num_sgs; i++)
475 residue += desc->sg[i].len;
476
477 if (next_sg != 0) {
478 count = jz4740_dma_read(dmadev,
479 JZ_REG_DMA_TRANSFER_COUNT(chan->id));
480 residue += count << chan->transfer_shift;
481 }
482
483 return residue;
484 }
485
jz4740_dma_tx_status(struct dma_chan * c,dma_cookie_t cookie,struct dma_tx_state * state)486 static enum dma_status jz4740_dma_tx_status(struct dma_chan *c,
487 dma_cookie_t cookie, struct dma_tx_state *state)
488 {
489 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
490 struct virt_dma_desc *vdesc;
491 enum dma_status status;
492 unsigned long flags;
493
494 status = dma_cookie_status(c, cookie, state);
495 if (status == DMA_COMPLETE || !state)
496 return status;
497
498 spin_lock_irqsave(&chan->vchan.lock, flags);
499 vdesc = vchan_find_desc(&chan->vchan, cookie);
500 if (cookie == chan->desc->vdesc.tx.cookie) {
501 state->residue = jz4740_dma_desc_residue(chan, chan->desc,
502 chan->next_sg);
503 } else if (vdesc) {
504 state->residue = jz4740_dma_desc_residue(chan,
505 to_jz4740_dma_desc(vdesc), 0);
506 } else {
507 state->residue = 0;
508 }
509 spin_unlock_irqrestore(&chan->vchan.lock, flags);
510
511 return status;
512 }
513
jz4740_dma_alloc_chan_resources(struct dma_chan * c)514 static int jz4740_dma_alloc_chan_resources(struct dma_chan *c)
515 {
516 return 0;
517 }
518
jz4740_dma_free_chan_resources(struct dma_chan * c)519 static void jz4740_dma_free_chan_resources(struct dma_chan *c)
520 {
521 vchan_free_chan_resources(to_virt_chan(c));
522 }
523
jz4740_dma_desc_free(struct virt_dma_desc * vdesc)524 static void jz4740_dma_desc_free(struct virt_dma_desc *vdesc)
525 {
526 kfree(container_of(vdesc, struct jz4740_dma_desc, vdesc));
527 }
528
jz4740_dma_probe(struct platform_device * pdev)529 static int jz4740_dma_probe(struct platform_device *pdev)
530 {
531 struct jz4740_dmaengine_chan *chan;
532 struct jz4740_dma_dev *dmadev;
533 struct dma_device *dd;
534 unsigned int i;
535 struct resource *res;
536 int ret;
537 int irq;
538
539 dmadev = devm_kzalloc(&pdev->dev, sizeof(*dmadev), GFP_KERNEL);
540 if (!dmadev)
541 return -EINVAL;
542
543 dd = &dmadev->ddev;
544
545 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
546 dmadev->base = devm_ioremap_resource(&pdev->dev, res);
547 if (IS_ERR(dmadev->base))
548 return PTR_ERR(dmadev->base);
549
550 dmadev->clk = clk_get(&pdev->dev, "dma");
551 if (IS_ERR(dmadev->clk))
552 return PTR_ERR(dmadev->clk);
553
554 clk_prepare_enable(dmadev->clk);
555
556 dma_cap_set(DMA_SLAVE, dd->cap_mask);
557 dma_cap_set(DMA_CYCLIC, dd->cap_mask);
558 dd->device_alloc_chan_resources = jz4740_dma_alloc_chan_resources;
559 dd->device_free_chan_resources = jz4740_dma_free_chan_resources;
560 dd->device_tx_status = jz4740_dma_tx_status;
561 dd->device_issue_pending = jz4740_dma_issue_pending;
562 dd->device_prep_slave_sg = jz4740_dma_prep_slave_sg;
563 dd->device_prep_dma_cyclic = jz4740_dma_prep_dma_cyclic;
564 dd->device_control = jz4740_dma_control;
565 dd->dev = &pdev->dev;
566 dd->chancnt = JZ_DMA_NR_CHANS;
567 INIT_LIST_HEAD(&dd->channels);
568
569 for (i = 0; i < dd->chancnt; i++) {
570 chan = &dmadev->chan[i];
571 chan->id = i;
572 chan->vchan.desc_free = jz4740_dma_desc_free;
573 vchan_init(&chan->vchan, dd);
574 }
575
576 ret = dma_async_device_register(dd);
577 if (ret)
578 return ret;
579
580 irq = platform_get_irq(pdev, 0);
581 ret = request_irq(irq, jz4740_dma_irq, 0, dev_name(&pdev->dev), dmadev);
582 if (ret)
583 goto err_unregister;
584
585 platform_set_drvdata(pdev, dmadev);
586
587 return 0;
588
589 err_unregister:
590 dma_async_device_unregister(dd);
591 return ret;
592 }
593
jz4740_dma_remove(struct platform_device * pdev)594 static int jz4740_dma_remove(struct platform_device *pdev)
595 {
596 struct jz4740_dma_dev *dmadev = platform_get_drvdata(pdev);
597 int irq = platform_get_irq(pdev, 0);
598
599 free_irq(irq, dmadev);
600 dma_async_device_unregister(&dmadev->ddev);
601 clk_disable_unprepare(dmadev->clk);
602
603 return 0;
604 }
605
606 static struct platform_driver jz4740_dma_driver = {
607 .probe = jz4740_dma_probe,
608 .remove = jz4740_dma_remove,
609 .driver = {
610 .name = "jz4740-dma",
611 .owner = THIS_MODULE,
612 },
613 };
614 module_platform_driver(jz4740_dma_driver);
615
616 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
617 MODULE_DESCRIPTION("JZ4740 DMA driver");
618 MODULE_LICENSE("GPL v2");
619