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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm...
[deliverable/linux.git] / drivers / dma / mxs-dma.c
1 /*
2 * Copyright 2011 Freescale Semiconductor, Inc. All Rights Reserved.
3 *
4 * Refer to drivers/dma/imx-sdma.c
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11 #include <linux/init.h>
12 #include <linux/types.h>
13 #include <linux/mm.h>
14 #include <linux/interrupt.h>
15 #include <linux/clk.h>
16 #include <linux/wait.h>
17 #include <linux/sched.h>
18 #include <linux/semaphore.h>
19 #include <linux/device.h>
20 #include <linux/dma-mapping.h>
21 #include <linux/slab.h>
22 #include <linux/platform_device.h>
23 #include <linux/dmaengine.h>
24 #include <linux/delay.h>
25 #include <linux/fsl/mxs-dma.h>
26
27 #include <asm/irq.h>
28 #include <mach/mxs.h>
29 #include <mach/common.h>
30
31 #include "dmaengine.h"
32
33 /*
34 * NOTE: The term "PIO" throughout the mxs-dma implementation means
35 * PIO mode of mxs apbh-dma and apbx-dma. With this working mode,
36 * dma can program the controller registers of peripheral devices.
37 */
38
39 #define MXS_DMA_APBH 0
40 #define MXS_DMA_APBX 1
41 #define dma_is_apbh() (mxs_dma->dev_id == MXS_DMA_APBH)
42
43 #define APBH_VERSION_LATEST 3
44 #define apbh_is_old() (mxs_dma->version < APBH_VERSION_LATEST)
45
46 #define HW_APBHX_CTRL0 0x000
47 #define BM_APBH_CTRL0_APB_BURST8_EN (1 << 29)
48 #define BM_APBH_CTRL0_APB_BURST_EN (1 << 28)
49 #define BP_APBH_CTRL0_RESET_CHANNEL 16
50 #define HW_APBHX_CTRL1 0x010
51 #define HW_APBHX_CTRL2 0x020
52 #define HW_APBHX_CHANNEL_CTRL 0x030
53 #define BP_APBHX_CHANNEL_CTRL_RESET_CHANNEL 16
54 #define HW_APBH_VERSION (cpu_is_mx23() ? 0x3f0 : 0x800)
55 #define HW_APBX_VERSION 0x800
56 #define BP_APBHX_VERSION_MAJOR 24
57 #define HW_APBHX_CHn_NXTCMDAR(n) \
58 (((dma_is_apbh() && apbh_is_old()) ? 0x050 : 0x110) + (n) * 0x70)
59 #define HW_APBHX_CHn_SEMA(n) \
60 (((dma_is_apbh() && apbh_is_old()) ? 0x080 : 0x140) + (n) * 0x70)
61
62 /*
63 * ccw bits definitions
64 *
65 * COMMAND: 0..1 (2)
66 * CHAIN: 2 (1)
67 * IRQ: 3 (1)
68 * NAND_LOCK: 4 (1) - not implemented
69 * NAND_WAIT4READY: 5 (1) - not implemented
70 * DEC_SEM: 6 (1)
71 * WAIT4END: 7 (1)
72 * HALT_ON_TERMINATE: 8 (1)
73 * TERMINATE_FLUSH: 9 (1)
74 * RESERVED: 10..11 (2)
75 * PIO_NUM: 12..15 (4)
76 */
77 #define BP_CCW_COMMAND 0
78 #define BM_CCW_COMMAND (3 << 0)
79 #define CCW_CHAIN (1 << 2)
80 #define CCW_IRQ (1 << 3)
81 #define CCW_DEC_SEM (1 << 6)
82 #define CCW_WAIT4END (1 << 7)
83 #define CCW_HALT_ON_TERM (1 << 8)
84 #define CCW_TERM_FLUSH (1 << 9)
85 #define BP_CCW_PIO_NUM 12
86 #define BM_CCW_PIO_NUM (0xf << 12)
87
88 #define BF_CCW(value, field) (((value) << BP_CCW_##field) & BM_CCW_##field)
89
90 #define MXS_DMA_CMD_NO_XFER 0
91 #define MXS_DMA_CMD_WRITE 1
92 #define MXS_DMA_CMD_READ 2
93 #define MXS_DMA_CMD_DMA_SENSE 3 /* not implemented */
94
95 struct mxs_dma_ccw {
96 u32 next;
97 u16 bits;
98 u16 xfer_bytes;
99 #define MAX_XFER_BYTES 0xff00
100 u32 bufaddr;
101 #define MXS_PIO_WORDS 16
102 u32 pio_words[MXS_PIO_WORDS];
103 };
104
105 #define NUM_CCW (int)(PAGE_SIZE / sizeof(struct mxs_dma_ccw))
106
107 struct mxs_dma_chan {
108 struct mxs_dma_engine *mxs_dma;
109 struct dma_chan chan;
110 struct dma_async_tx_descriptor desc;
111 struct tasklet_struct tasklet;
112 int chan_irq;
113 struct mxs_dma_ccw *ccw;
114 dma_addr_t ccw_phys;
115 int desc_count;
116 enum dma_status status;
117 unsigned int flags;
118 #define MXS_DMA_SG_LOOP (1 << 0)
119 };
120
121 #define MXS_DMA_CHANNELS 16
122 #define MXS_DMA_CHANNELS_MASK 0xffff
123
124 struct mxs_dma_engine {
125 int dev_id;
126 unsigned int version;
127 void __iomem *base;
128 struct clk *clk;
129 struct dma_device dma_device;
130 struct device_dma_parameters dma_parms;
131 struct mxs_dma_chan mxs_chans[MXS_DMA_CHANNELS];
132 };
133
134 static void mxs_dma_reset_chan(struct mxs_dma_chan *mxs_chan)
135 {
136 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
137 int chan_id = mxs_chan->chan.chan_id;
138
139 if (dma_is_apbh() && apbh_is_old())
140 writel(1 << (chan_id + BP_APBH_CTRL0_RESET_CHANNEL),
141 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
142 else
143 writel(1 << (chan_id + BP_APBHX_CHANNEL_CTRL_RESET_CHANNEL),
144 mxs_dma->base + HW_APBHX_CHANNEL_CTRL + MXS_SET_ADDR);
145 }
146
147 static void mxs_dma_enable_chan(struct mxs_dma_chan *mxs_chan)
148 {
149 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
150 int chan_id = mxs_chan->chan.chan_id;
151
152 /* set cmd_addr up */
153 writel(mxs_chan->ccw_phys,
154 mxs_dma->base + HW_APBHX_CHn_NXTCMDAR(chan_id));
155
156 /* write 1 to SEMA to kick off the channel */
157 writel(1, mxs_dma->base + HW_APBHX_CHn_SEMA(chan_id));
158 }
159
160 static void mxs_dma_disable_chan(struct mxs_dma_chan *mxs_chan)
161 {
162 mxs_chan->status = DMA_SUCCESS;
163 }
164
165 static void mxs_dma_pause_chan(struct mxs_dma_chan *mxs_chan)
166 {
167 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
168 int chan_id = mxs_chan->chan.chan_id;
169
170 /* freeze the channel */
171 if (dma_is_apbh() && apbh_is_old())
172 writel(1 << chan_id,
173 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
174 else
175 writel(1 << chan_id,
176 mxs_dma->base + HW_APBHX_CHANNEL_CTRL + MXS_SET_ADDR);
177
178 mxs_chan->status = DMA_PAUSED;
179 }
180
181 static void mxs_dma_resume_chan(struct mxs_dma_chan *mxs_chan)
182 {
183 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
184 int chan_id = mxs_chan->chan.chan_id;
185
186 /* unfreeze the channel */
187 if (dma_is_apbh() && apbh_is_old())
188 writel(1 << chan_id,
189 mxs_dma->base + HW_APBHX_CTRL0 + MXS_CLR_ADDR);
190 else
191 writel(1 << chan_id,
192 mxs_dma->base + HW_APBHX_CHANNEL_CTRL + MXS_CLR_ADDR);
193
194 mxs_chan->status = DMA_IN_PROGRESS;
195 }
196
197 static struct mxs_dma_chan *to_mxs_dma_chan(struct dma_chan *chan)
198 {
199 return container_of(chan, struct mxs_dma_chan, chan);
200 }
201
202 static dma_cookie_t mxs_dma_tx_submit(struct dma_async_tx_descriptor *tx)
203 {
204 return dma_cookie_assign(tx);
205 }
206
207 static void mxs_dma_tasklet(unsigned long data)
208 {
209 struct mxs_dma_chan *mxs_chan = (struct mxs_dma_chan *) data;
210
211 if (mxs_chan->desc.callback)
212 mxs_chan->desc.callback(mxs_chan->desc.callback_param);
213 }
214
215 static irqreturn_t mxs_dma_int_handler(int irq, void *dev_id)
216 {
217 struct mxs_dma_engine *mxs_dma = dev_id;
218 u32 stat1, stat2;
219
220 /* completion status */
221 stat1 = readl(mxs_dma->base + HW_APBHX_CTRL1);
222 stat1 &= MXS_DMA_CHANNELS_MASK;
223 writel(stat1, mxs_dma->base + HW_APBHX_CTRL1 + MXS_CLR_ADDR);
224
225 /* error status */
226 stat2 = readl(mxs_dma->base + HW_APBHX_CTRL2);
227 writel(stat2, mxs_dma->base + HW_APBHX_CTRL2 + MXS_CLR_ADDR);
228
229 /*
230 * When both completion and error of termination bits set at the
231 * same time, we do not take it as an error. IOW, it only becomes
232 * an error we need to handle here in case of either it's (1) a bus
233 * error or (2) a termination error with no completion.
234 */
235 stat2 = ((stat2 >> MXS_DMA_CHANNELS) & stat2) | /* (1) */
236 (~(stat2 >> MXS_DMA_CHANNELS) & stat2 & ~stat1); /* (2) */
237
238 /* combine error and completion status for checking */
239 stat1 = (stat2 << MXS_DMA_CHANNELS) | stat1;
240 while (stat1) {
241 int channel = fls(stat1) - 1;
242 struct mxs_dma_chan *mxs_chan =
243 &mxs_dma->mxs_chans[channel % MXS_DMA_CHANNELS];
244
245 if (channel >= MXS_DMA_CHANNELS) {
246 dev_dbg(mxs_dma->dma_device.dev,
247 "%s: error in channel %d\n", __func__,
248 channel - MXS_DMA_CHANNELS);
249 mxs_chan->status = DMA_ERROR;
250 mxs_dma_reset_chan(mxs_chan);
251 } else {
252 if (mxs_chan->flags & MXS_DMA_SG_LOOP)
253 mxs_chan->status = DMA_IN_PROGRESS;
254 else
255 mxs_chan->status = DMA_SUCCESS;
256 }
257
258 stat1 &= ~(1 << channel);
259
260 if (mxs_chan->status == DMA_SUCCESS)
261 dma_cookie_complete(&mxs_chan->desc);
262
263 /* schedule tasklet on this channel */
264 tasklet_schedule(&mxs_chan->tasklet);
265 }
266
267 return IRQ_HANDLED;
268 }
269
270 static int mxs_dma_alloc_chan_resources(struct dma_chan *chan)
271 {
272 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
273 struct mxs_dma_data *data = chan->private;
274 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
275 int ret;
276
277 if (!data)
278 return -EINVAL;
279
280 mxs_chan->chan_irq = data->chan_irq;
281
282 mxs_chan->ccw = dma_alloc_coherent(mxs_dma->dma_device.dev, PAGE_SIZE,
283 &mxs_chan->ccw_phys, GFP_KERNEL);
284 if (!mxs_chan->ccw) {
285 ret = -ENOMEM;
286 goto err_alloc;
287 }
288
289 memset(mxs_chan->ccw, 0, PAGE_SIZE);
290
291 if (mxs_chan->chan_irq != NO_IRQ) {
292 ret = request_irq(mxs_chan->chan_irq, mxs_dma_int_handler,
293 0, "mxs-dma", mxs_dma);
294 if (ret)
295 goto err_irq;
296 }
297
298 ret = clk_prepare_enable(mxs_dma->clk);
299 if (ret)
300 goto err_clk;
301
302 mxs_dma_reset_chan(mxs_chan);
303
304 dma_async_tx_descriptor_init(&mxs_chan->desc, chan);
305 mxs_chan->desc.tx_submit = mxs_dma_tx_submit;
306
307 /* the descriptor is ready */
308 async_tx_ack(&mxs_chan->desc);
309
310 return 0;
311
312 err_clk:
313 free_irq(mxs_chan->chan_irq, mxs_dma);
314 err_irq:
315 dma_free_coherent(mxs_dma->dma_device.dev, PAGE_SIZE,
316 mxs_chan->ccw, mxs_chan->ccw_phys);
317 err_alloc:
318 return ret;
319 }
320
321 static void mxs_dma_free_chan_resources(struct dma_chan *chan)
322 {
323 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
324 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
325
326 mxs_dma_disable_chan(mxs_chan);
327
328 free_irq(mxs_chan->chan_irq, mxs_dma);
329
330 dma_free_coherent(mxs_dma->dma_device.dev, PAGE_SIZE,
331 mxs_chan->ccw, mxs_chan->ccw_phys);
332
333 clk_disable_unprepare(mxs_dma->clk);
334 }
335
336 /*
337 * How to use the flags for ->device_prep_slave_sg() :
338 * [1] If there is only one DMA command in the DMA chain, the code should be:
339 * ......
340 * ->device_prep_slave_sg(DMA_CTRL_ACK);
341 * ......
342 * [2] If there are two DMA commands in the DMA chain, the code should be
343 * ......
344 * ->device_prep_slave_sg(0);
345 * ......
346 * ->device_prep_slave_sg(DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
347 * ......
348 * [3] If there are more than two DMA commands in the DMA chain, the code
349 * should be:
350 * ......
351 * ->device_prep_slave_sg(0); // First
352 * ......
353 * ->device_prep_slave_sg(DMA_PREP_INTERRUPT [| DMA_CTRL_ACK]);
354 * ......
355 * ->device_prep_slave_sg(DMA_PREP_INTERRUPT | DMA_CTRL_ACK); // Last
356 * ......
357 */
358 static struct dma_async_tx_descriptor *mxs_dma_prep_slave_sg(
359 struct dma_chan *chan, struct scatterlist *sgl,
360 unsigned int sg_len, enum dma_transfer_direction direction,
361 unsigned long flags, void *context)
362 {
363 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
364 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
365 struct mxs_dma_ccw *ccw;
366 struct scatterlist *sg;
367 int i, j;
368 u32 *pio;
369 bool append = flags & DMA_PREP_INTERRUPT;
370 int idx = append ? mxs_chan->desc_count : 0;
371
372 if (mxs_chan->status == DMA_IN_PROGRESS && !append)
373 return NULL;
374
375 if (sg_len + (append ? idx : 0) > NUM_CCW) {
376 dev_err(mxs_dma->dma_device.dev,
377 "maximum number of sg exceeded: %d > %d\n",
378 sg_len, NUM_CCW);
379 goto err_out;
380 }
381
382 mxs_chan->status = DMA_IN_PROGRESS;
383 mxs_chan->flags = 0;
384
385 /*
386 * If the sg is prepared with append flag set, the sg
387 * will be appended to the last prepared sg.
388 */
389 if (append) {
390 BUG_ON(idx < 1);
391 ccw = &mxs_chan->ccw[idx - 1];
392 ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * idx;
393 ccw->bits |= CCW_CHAIN;
394 ccw->bits &= ~CCW_IRQ;
395 ccw->bits &= ~CCW_DEC_SEM;
396 } else {
397 idx = 0;
398 }
399
400 if (direction == DMA_TRANS_NONE) {
401 ccw = &mxs_chan->ccw[idx++];
402 pio = (u32 *) sgl;
403
404 for (j = 0; j < sg_len;)
405 ccw->pio_words[j++] = *pio++;
406
407 ccw->bits = 0;
408 ccw->bits |= CCW_IRQ;
409 ccw->bits |= CCW_DEC_SEM;
410 if (flags & DMA_CTRL_ACK)
411 ccw->bits |= CCW_WAIT4END;
412 ccw->bits |= CCW_HALT_ON_TERM;
413 ccw->bits |= CCW_TERM_FLUSH;
414 ccw->bits |= BF_CCW(sg_len, PIO_NUM);
415 ccw->bits |= BF_CCW(MXS_DMA_CMD_NO_XFER, COMMAND);
416 } else {
417 for_each_sg(sgl, sg, sg_len, i) {
418 if (sg->length > MAX_XFER_BYTES) {
419 dev_err(mxs_dma->dma_device.dev, "maximum bytes for sg entry exceeded: %d > %d\n",
420 sg->length, MAX_XFER_BYTES);
421 goto err_out;
422 }
423
424 ccw = &mxs_chan->ccw[idx++];
425
426 ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * idx;
427 ccw->bufaddr = sg->dma_address;
428 ccw->xfer_bytes = sg->length;
429
430 ccw->bits = 0;
431 ccw->bits |= CCW_CHAIN;
432 ccw->bits |= CCW_HALT_ON_TERM;
433 ccw->bits |= CCW_TERM_FLUSH;
434 ccw->bits |= BF_CCW(direction == DMA_DEV_TO_MEM ?
435 MXS_DMA_CMD_WRITE : MXS_DMA_CMD_READ,
436 COMMAND);
437
438 if (i + 1 == sg_len) {
439 ccw->bits &= ~CCW_CHAIN;
440 ccw->bits |= CCW_IRQ;
441 ccw->bits |= CCW_DEC_SEM;
442 if (flags & DMA_CTRL_ACK)
443 ccw->bits |= CCW_WAIT4END;
444 }
445 }
446 }
447 mxs_chan->desc_count = idx;
448
449 return &mxs_chan->desc;
450
451 err_out:
452 mxs_chan->status = DMA_ERROR;
453 return NULL;
454 }
455
456 static struct dma_async_tx_descriptor *mxs_dma_prep_dma_cyclic(
457 struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
458 size_t period_len, enum dma_transfer_direction direction,
459 void *context)
460 {
461 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
462 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
463 int num_periods = buf_len / period_len;
464 int i = 0, buf = 0;
465
466 if (mxs_chan->status == DMA_IN_PROGRESS)
467 return NULL;
468
469 mxs_chan->status = DMA_IN_PROGRESS;
470 mxs_chan->flags |= MXS_DMA_SG_LOOP;
471
472 if (num_periods > NUM_CCW) {
473 dev_err(mxs_dma->dma_device.dev,
474 "maximum number of sg exceeded: %d > %d\n",
475 num_periods, NUM_CCW);
476 goto err_out;
477 }
478
479 if (period_len > MAX_XFER_BYTES) {
480 dev_err(mxs_dma->dma_device.dev,
481 "maximum period size exceeded: %d > %d\n",
482 period_len, MAX_XFER_BYTES);
483 goto err_out;
484 }
485
486 while (buf < buf_len) {
487 struct mxs_dma_ccw *ccw = &mxs_chan->ccw[i];
488
489 if (i + 1 == num_periods)
490 ccw->next = mxs_chan->ccw_phys;
491 else
492 ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * (i + 1);
493
494 ccw->bufaddr = dma_addr;
495 ccw->xfer_bytes = period_len;
496
497 ccw->bits = 0;
498 ccw->bits |= CCW_CHAIN;
499 ccw->bits |= CCW_IRQ;
500 ccw->bits |= CCW_HALT_ON_TERM;
501 ccw->bits |= CCW_TERM_FLUSH;
502 ccw->bits |= BF_CCW(direction == DMA_DEV_TO_MEM ?
503 MXS_DMA_CMD_WRITE : MXS_DMA_CMD_READ, COMMAND);
504
505 dma_addr += period_len;
506 buf += period_len;
507
508 i++;
509 }
510 mxs_chan->desc_count = i;
511
512 return &mxs_chan->desc;
513
514 err_out:
515 mxs_chan->status = DMA_ERROR;
516 return NULL;
517 }
518
519 static int mxs_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
520 unsigned long arg)
521 {
522 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
523 int ret = 0;
524
525 switch (cmd) {
526 case DMA_TERMINATE_ALL:
527 mxs_dma_reset_chan(mxs_chan);
528 mxs_dma_disable_chan(mxs_chan);
529 break;
530 case DMA_PAUSE:
531 mxs_dma_pause_chan(mxs_chan);
532 break;
533 case DMA_RESUME:
534 mxs_dma_resume_chan(mxs_chan);
535 break;
536 default:
537 ret = -ENOSYS;
538 }
539
540 return ret;
541 }
542
543 static enum dma_status mxs_dma_tx_status(struct dma_chan *chan,
544 dma_cookie_t cookie, struct dma_tx_state *txstate)
545 {
546 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
547 dma_cookie_t last_used;
548
549 last_used = chan->cookie;
550 dma_set_tx_state(txstate, chan->completed_cookie, last_used, 0);
551
552 return mxs_chan->status;
553 }
554
555 static void mxs_dma_issue_pending(struct dma_chan *chan)
556 {
557 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
558
559 mxs_dma_enable_chan(mxs_chan);
560 }
561
562 static int __init mxs_dma_init(struct mxs_dma_engine *mxs_dma)
563 {
564 int ret;
565
566 ret = clk_prepare_enable(mxs_dma->clk);
567 if (ret)
568 return ret;
569
570 ret = mxs_reset_block(mxs_dma->base);
571 if (ret)
572 goto err_out;
573
574 /* only major version matters */
575 mxs_dma->version = readl(mxs_dma->base +
576 ((mxs_dma->dev_id == MXS_DMA_APBX) ?
577 HW_APBX_VERSION : HW_APBH_VERSION)) >>
578 BP_APBHX_VERSION_MAJOR;
579
580 /* enable apbh burst */
581 if (dma_is_apbh()) {
582 writel(BM_APBH_CTRL0_APB_BURST_EN,
583 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
584 writel(BM_APBH_CTRL0_APB_BURST8_EN,
585 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
586 }
587
588 /* enable irq for all the channels */
589 writel(MXS_DMA_CHANNELS_MASK << MXS_DMA_CHANNELS,
590 mxs_dma->base + HW_APBHX_CTRL1 + MXS_SET_ADDR);
591
592 err_out:
593 clk_disable_unprepare(mxs_dma->clk);
594 return ret;
595 }
596
597 static int __init mxs_dma_probe(struct platform_device *pdev)
598 {
599 const struct platform_device_id *id_entry =
600 platform_get_device_id(pdev);
601 struct mxs_dma_engine *mxs_dma;
602 struct resource *iores;
603 int ret, i;
604
605 mxs_dma = kzalloc(sizeof(*mxs_dma), GFP_KERNEL);
606 if (!mxs_dma)
607 return -ENOMEM;
608
609 mxs_dma->dev_id = id_entry->driver_data;
610
611 iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
612
613 if (!request_mem_region(iores->start, resource_size(iores),
614 pdev->name)) {
615 ret = -EBUSY;
616 goto err_request_region;
617 }
618
619 mxs_dma->base = ioremap(iores->start, resource_size(iores));
620 if (!mxs_dma->base) {
621 ret = -ENOMEM;
622 goto err_ioremap;
623 }
624
625 mxs_dma->clk = clk_get(&pdev->dev, NULL);
626 if (IS_ERR(mxs_dma->clk)) {
627 ret = PTR_ERR(mxs_dma->clk);
628 goto err_clk;
629 }
630
631 dma_cap_set(DMA_SLAVE, mxs_dma->dma_device.cap_mask);
632 dma_cap_set(DMA_CYCLIC, mxs_dma->dma_device.cap_mask);
633
634 INIT_LIST_HEAD(&mxs_dma->dma_device.channels);
635
636 /* Initialize channel parameters */
637 for (i = 0; i < MXS_DMA_CHANNELS; i++) {
638 struct mxs_dma_chan *mxs_chan = &mxs_dma->mxs_chans[i];
639
640 mxs_chan->mxs_dma = mxs_dma;
641 mxs_chan->chan.device = &mxs_dma->dma_device;
642 dma_cookie_init(&mxs_chan->chan);
643
644 tasklet_init(&mxs_chan->tasklet, mxs_dma_tasklet,
645 (unsigned long) mxs_chan);
646
647
648 /* Add the channel to mxs_chan list */
649 list_add_tail(&mxs_chan->chan.device_node,
650 &mxs_dma->dma_device.channels);
651 }
652
653 ret = mxs_dma_init(mxs_dma);
654 if (ret)
655 goto err_init;
656
657 mxs_dma->dma_device.dev = &pdev->dev;
658
659 /* mxs_dma gets 65535 bytes maximum sg size */
660 mxs_dma->dma_device.dev->dma_parms = &mxs_dma->dma_parms;
661 dma_set_max_seg_size(mxs_dma->dma_device.dev, MAX_XFER_BYTES);
662
663 mxs_dma->dma_device.device_alloc_chan_resources = mxs_dma_alloc_chan_resources;
664 mxs_dma->dma_device.device_free_chan_resources = mxs_dma_free_chan_resources;
665 mxs_dma->dma_device.device_tx_status = mxs_dma_tx_status;
666 mxs_dma->dma_device.device_prep_slave_sg = mxs_dma_prep_slave_sg;
667 mxs_dma->dma_device.device_prep_dma_cyclic = mxs_dma_prep_dma_cyclic;
668 mxs_dma->dma_device.device_control = mxs_dma_control;
669 mxs_dma->dma_device.device_issue_pending = mxs_dma_issue_pending;
670
671 ret = dma_async_device_register(&mxs_dma->dma_device);
672 if (ret) {
673 dev_err(mxs_dma->dma_device.dev, "unable to register\n");
674 goto err_init;
675 }
676
677 dev_info(mxs_dma->dma_device.dev, "initialized\n");
678
679 return 0;
680
681 err_init:
682 clk_put(mxs_dma->clk);
683 err_clk:
684 iounmap(mxs_dma->base);
685 err_ioremap:
686 release_mem_region(iores->start, resource_size(iores));
687 err_request_region:
688 kfree(mxs_dma);
689 return ret;
690 }
691
692 static struct platform_device_id mxs_dma_type[] = {
693 {
694 .name = "mxs-dma-apbh",
695 .driver_data = MXS_DMA_APBH,
696 }, {
697 .name = "mxs-dma-apbx",
698 .driver_data = MXS_DMA_APBX,
699 }, {
700 /* end of list */
701 }
702 };
703
704 static struct platform_driver mxs_dma_driver = {
705 .driver = {
706 .name = "mxs-dma",
707 },
708 .id_table = mxs_dma_type,
709 };
710
711 static int __init mxs_dma_module_init(void)
712 {
713 return platform_driver_probe(&mxs_dma_driver, mxs_dma_probe);
714 }
715 subsys_initcall(mxs_dma_module_init);
Linux kernel - Deliverables
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