?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
asix: fix infinite loop in rx_fixup()
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / dma / mxs-dma.c
blobbe641cbd36fcb30c16aafaf25f279ecc0064b07a
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
26 #include <asm/irq.h>
27 #include <mach/mxs.h>
28 #include <mach/dma.h>
29 #include <mach/common.h>
30
31 /*
32 * NOTE: The term "PIO" throughout the mxs-dma implementation means
33 * PIO mode of mxs apbh-dma and apbx-dma. With this working mode,
34 * dma can program the controller registers of peripheral devices.
35 */
36
37 #define MXS_DMA_APBH 0
38 #define MXS_DMA_APBX 1
39 #define dma_is_apbh() (mxs_dma->dev_id == MXS_DMA_APBH)
40
41 #define APBH_VERSION_LATEST 3
42 #define apbh_is_old() (mxs_dma->version < APBH_VERSION_LATEST)
43
44 #define HW_APBHX_CTRL0 0x000
45 #define BM_APBH_CTRL0_APB_BURST8_EN (1 << 29)
46 #define BM_APBH_CTRL0_APB_BURST_EN (1 << 28)
47 #define BP_APBH_CTRL0_CLKGATE_CHANNEL 8
48 #define BP_APBH_CTRL0_RESET_CHANNEL 16
49 #define HW_APBHX_CTRL1 0x010
50 #define HW_APBHX_CTRL2 0x020
51 #define HW_APBHX_CHANNEL_CTRL 0x030
52 #define BP_APBHX_CHANNEL_CTRL_RESET_CHANNEL 16
53 #define HW_APBH_VERSION (cpu_is_mx23() ? 0x3f0 : 0x800)
54 #define HW_APBX_VERSION 0x800
55 #define BP_APBHX_VERSION_MAJOR 24
56 #define HW_APBHX_CHn_NXTCMDAR(n) \
57 (((dma_is_apbh() && apbh_is_old()) ? 0x050 : 0x110) + (n) * 0x70)
58 #define HW_APBHX_CHn_SEMA(n) \
59 (((dma_is_apbh() && apbh_is_old()) ? 0x080 : 0x140) + (n) * 0x70)
60
61 /*
62 * ccw bits definitions
63 *
64 * COMMAND: 0..1 (2)
65 * CHAIN: 2 (1)
66 * IRQ: 3 (1)
67 * NAND_LOCK: 4 (1) - not implemented
68 * NAND_WAIT4READY: 5 (1) - not implemented
69 * DEC_SEM: 6 (1)
70 * WAIT4END: 7 (1)
71 * HALT_ON_TERMINATE: 8 (1)
72 * TERMINATE_FLUSH: 9 (1)
73 * RESERVED: 10..11 (2)
74 * PIO_NUM: 12..15 (4)
75 */
76 #define BP_CCW_COMMAND 0
77 #define BM_CCW_COMMAND (3 << 0)
78 #define CCW_CHAIN (1 << 2)
79 #define CCW_IRQ (1 << 3)
80 #define CCW_DEC_SEM (1 << 6)
81 #define CCW_WAIT4END (1 << 7)
82 #define CCW_HALT_ON_TERM (1 << 8)
83 #define CCW_TERM_FLUSH (1 << 9)
84 #define BP_CCW_PIO_NUM 12
85 #define BM_CCW_PIO_NUM (0xf << 12)
86
87 #define BF_CCW(value, field) (((value) << BP_CCW_##field) & BM_CCW_##field)
88
89 #define MXS_DMA_CMD_NO_XFER 0
90 #define MXS_DMA_CMD_WRITE 1
91 #define MXS_DMA_CMD_READ 2
92 #define MXS_DMA_CMD_DMA_SENSE 3 /* not implemented */
93
94 struct mxs_dma_ccw {
95 u32 next;
96 u16 bits;
97 u16 xfer_bytes;
98 #define MAX_XFER_BYTES 0xff00
99 u32 bufaddr;
100 #define MXS_PIO_WORDS 16
101 u32 pio_words[MXS_PIO_WORDS];
102 };
103
104 #define NUM_CCW (int)(PAGE_SIZE / sizeof(struct mxs_dma_ccw))
105
106 struct mxs_dma_chan {
107 struct mxs_dma_engine *mxs_dma;
108 struct dma_chan chan;
109 struct dma_async_tx_descriptor desc;
110 struct tasklet_struct tasklet;
111 int chan_irq;
112 struct mxs_dma_ccw *ccw;
113 dma_addr_t ccw_phys;
114 dma_cookie_t last_completed;
115 enum dma_status status;
116 unsigned int flags;
117 #define MXS_DMA_SG_LOOP (1 << 0)
118 };
119
120 #define MXS_DMA_CHANNELS 16
121 #define MXS_DMA_CHANNELS_MASK 0xffff
122
123 struct mxs_dma_engine {
124 int dev_id;
125 unsigned int version;
126 void __iomem *base;
127 struct clk *clk;
128 struct dma_device dma_device;
129 struct device_dma_parameters dma_parms;
130 struct mxs_dma_chan mxs_chans[MXS_DMA_CHANNELS];
131 };
132
133 static void mxs_dma_reset_chan(struct mxs_dma_chan *mxs_chan)
134 {
135 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
136 int chan_id = mxs_chan->chan.chan_id;
137
138 if (dma_is_apbh() && apbh_is_old())
139 writel(1 << (chan_id + BP_APBH_CTRL0_RESET_CHANNEL),
140 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
141 else
142 writel(1 << (chan_id + BP_APBHX_CHANNEL_CTRL_RESET_CHANNEL),
143 mxs_dma->base + HW_APBHX_CHANNEL_CTRL + MXS_SET_ADDR);
144 }
145
146 static void mxs_dma_enable_chan(struct mxs_dma_chan *mxs_chan)
147 {
148 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
149 int chan_id = mxs_chan->chan.chan_id;
150
151 /* set cmd_addr up */
152 writel(mxs_chan->ccw_phys,
153 mxs_dma->base + HW_APBHX_CHn_NXTCMDAR(chan_id));
154
155 /* enable apbh channel clock */
156 if (dma_is_apbh()) {
157 if (apbh_is_old())
158 writel(1 << (chan_id + BP_APBH_CTRL0_CLKGATE_CHANNEL),
159 mxs_dma->base + HW_APBHX_CTRL0 + MXS_CLR_ADDR);
160 else
161 writel(1 << chan_id,
162 mxs_dma->base + HW_APBHX_CTRL0 + MXS_CLR_ADDR);
163 }
164
165 /* write 1 to SEMA to kick off the channel */
166 writel(1, mxs_dma->base + HW_APBHX_CHn_SEMA(chan_id));
167 }
168
169 static void mxs_dma_disable_chan(struct mxs_dma_chan *mxs_chan)
170 {
171 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
172 int chan_id = mxs_chan->chan.chan_id;
173
174 /* disable apbh channel clock */
175 if (dma_is_apbh()) {
176 if (apbh_is_old())
177 writel(1 << (chan_id + BP_APBH_CTRL0_CLKGATE_CHANNEL),
178 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
179 else
180 writel(1 << chan_id,
181 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
182 }
183
184 mxs_chan->status = DMA_SUCCESS;
185 }
186
187 static void mxs_dma_pause_chan(struct mxs_dma_chan *mxs_chan)
188 {
189 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
190 int chan_id = mxs_chan->chan.chan_id;
191
192 /* freeze the channel */
193 if (dma_is_apbh() && apbh_is_old())
194 writel(1 << chan_id,
195 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
196 else
197 writel(1 << chan_id,
198 mxs_dma->base + HW_APBHX_CHANNEL_CTRL + MXS_SET_ADDR);
199
200 mxs_chan->status = DMA_PAUSED;
201 }
202
203 static void mxs_dma_resume_chan(struct mxs_dma_chan *mxs_chan)
204 {
205 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
206 int chan_id = mxs_chan->chan.chan_id;
207
208 /* unfreeze the channel */
209 if (dma_is_apbh() && apbh_is_old())
210 writel(1 << chan_id,
211 mxs_dma->base + HW_APBHX_CTRL0 + MXS_CLR_ADDR);
212 else
213 writel(1 << chan_id,
214 mxs_dma->base + HW_APBHX_CHANNEL_CTRL + MXS_CLR_ADDR);
215
216 mxs_chan->status = DMA_IN_PROGRESS;
217 }
218
219 static dma_cookie_t mxs_dma_assign_cookie(struct mxs_dma_chan *mxs_chan)
220 {
221 dma_cookie_t cookie = mxs_chan->chan.cookie;
222
223 if (++cookie < 0)
224 cookie = 1;
225
226 mxs_chan->chan.cookie = cookie;
227 mxs_chan->desc.cookie = cookie;
228
229 return cookie;
230 }
231
232 static struct mxs_dma_chan *to_mxs_dma_chan(struct dma_chan *chan)
233 {
234 return container_of(chan, struct mxs_dma_chan, chan);
235 }
236
237 static dma_cookie_t mxs_dma_tx_submit(struct dma_async_tx_descriptor *tx)
238 {
239 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(tx->chan);
240
241 mxs_dma_enable_chan(mxs_chan);
242
243 return mxs_dma_assign_cookie(mxs_chan);
244 }
245
246 static void mxs_dma_tasklet(unsigned long data)
247 {
248 struct mxs_dma_chan *mxs_chan = (struct mxs_dma_chan *) data;
249
250 if (mxs_chan->desc.callback)
251 mxs_chan->desc.callback(mxs_chan->desc.callback_param);
252 }
253
254 static irqreturn_t mxs_dma_int_handler(int irq, void *dev_id)
255 {
256 struct mxs_dma_engine *mxs_dma = dev_id;
257 u32 stat1, stat2;
258
259 /* completion status */
260 stat1 = readl(mxs_dma->base + HW_APBHX_CTRL1);
261 stat1 &= MXS_DMA_CHANNELS_MASK;
262 writel(stat1, mxs_dma->base + HW_APBHX_CTRL1 + MXS_CLR_ADDR);
263
264 /* error status */
265 stat2 = readl(mxs_dma->base + HW_APBHX_CTRL2);
266 writel(stat2, mxs_dma->base + HW_APBHX_CTRL2 + MXS_CLR_ADDR);
267
268 /*
269 * When both completion and error of termination bits set at the
270 * same time, we do not take it as an error. IOW, it only becomes
271 * an error we need to handler here in case of ether it's (1) an bus
272 * error or (2) a termination error with no completion.
273 */
274 stat2 = ((stat2 >> MXS_DMA_CHANNELS) & stat2) | /* (1) */
275 (~(stat2 >> MXS_DMA_CHANNELS) & stat2 & ~stat1); /* (2) */
276
277 /* combine error and completion status for checking */
278 stat1 = (stat2 << MXS_DMA_CHANNELS) | stat1;
279 while (stat1) {
280 int channel = fls(stat1) - 1;
281 struct mxs_dma_chan *mxs_chan =
282 &mxs_dma->mxs_chans[channel % MXS_DMA_CHANNELS];
283
284 if (channel >= MXS_DMA_CHANNELS) {
285 dev_dbg(mxs_dma->dma_device.dev,
286 "%s: error in channel %d\n", __func__,
287 channel - MXS_DMA_CHANNELS);
288 mxs_chan->status = DMA_ERROR;
289 mxs_dma_reset_chan(mxs_chan);
290 } else {
291 if (mxs_chan->flags & MXS_DMA_SG_LOOP)
292 mxs_chan->status = DMA_IN_PROGRESS;
293 else
294 mxs_chan->status = DMA_SUCCESS;
295 }
296
297 stat1 &= ~(1 << channel);
298
299 if (mxs_chan->status == DMA_SUCCESS)
300 mxs_chan->last_completed = mxs_chan->desc.cookie;
301
302 /* schedule tasklet on this channel */
303 tasklet_schedule(&mxs_chan->tasklet);
304 }
305
306 return IRQ_HANDLED;
307 }
308
309 static int mxs_dma_alloc_chan_resources(struct dma_chan *chan)
310 {
311 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
312 struct mxs_dma_data *data = chan->private;
313 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
314 int ret;
315
316 if (!data)
317 return -EINVAL;
318
319 mxs_chan->chan_irq = data->chan_irq;
320
321 mxs_chan->ccw = dma_alloc_coherent(mxs_dma->dma_device.dev, PAGE_SIZE,
322 &mxs_chan->ccw_phys, GFP_KERNEL);
323 if (!mxs_chan->ccw) {
324 ret = -ENOMEM;
325 goto err_alloc;
326 }
327
328 memset(mxs_chan->ccw, 0, PAGE_SIZE);
329
330 if (mxs_chan->chan_irq != NO_IRQ) {
331 ret = request_irq(mxs_chan->chan_irq, mxs_dma_int_handler,
332 0, "mxs-dma", mxs_dma);
333 if (ret)
334 goto err_irq;
335 }
336
337 ret = clk_enable(mxs_dma->clk);
338 if (ret)
339 goto err_clk;
340
341 mxs_dma_reset_chan(mxs_chan);
342
343 dma_async_tx_descriptor_init(&mxs_chan->desc, chan);
344 mxs_chan->desc.tx_submit = mxs_dma_tx_submit;
345
346 /* the descriptor is ready */
347 async_tx_ack(&mxs_chan->desc);
348
349 return 0;
350
351 err_clk:
352 free_irq(mxs_chan->chan_irq, mxs_dma);
353 err_irq:
354 dma_free_coherent(mxs_dma->dma_device.dev, PAGE_SIZE,
355 mxs_chan->ccw, mxs_chan->ccw_phys);
356 err_alloc:
357 return ret;
358 }
359
360 static void mxs_dma_free_chan_resources(struct dma_chan *chan)
361 {
362 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
363 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
364
365 mxs_dma_disable_chan(mxs_chan);
366
367 free_irq(mxs_chan->chan_irq, mxs_dma);
368
369 dma_free_coherent(mxs_dma->dma_device.dev, PAGE_SIZE,
370 mxs_chan->ccw, mxs_chan->ccw_phys);
371
372 clk_disable(mxs_dma->clk);
373 }
374
375 static struct dma_async_tx_descriptor *mxs_dma_prep_slave_sg(
376 struct dma_chan *chan, struct scatterlist *sgl,
377 unsigned int sg_len, enum dma_data_direction direction,
378 unsigned long append)
379 {
380 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
381 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
382 struct mxs_dma_ccw *ccw;
383 struct scatterlist *sg;
384 int i, j;
385 u32 *pio;
386 static int idx;
387
388 if (mxs_chan->status == DMA_IN_PROGRESS && !append)
389 return NULL;
390
391 if (sg_len + (append ? idx : 0) > NUM_CCW) {
392 dev_err(mxs_dma->dma_device.dev,
393 "maximum number of sg exceeded: %d > %d\n",
394 sg_len, NUM_CCW);
395 goto err_out;
396 }
397
398 mxs_chan->status = DMA_IN_PROGRESS;
399 mxs_chan->flags = 0;
400
401 /*
402 * If the sg is prepared with append flag set, the sg
403 * will be appended to the last prepared sg.
404 */
405 if (append) {
406 BUG_ON(idx < 1);
407 ccw = &mxs_chan->ccw[idx - 1];
408 ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * idx;
409 ccw->bits |= CCW_CHAIN;
410 ccw->bits &= ~CCW_IRQ;
411 ccw->bits &= ~CCW_DEC_SEM;
412 ccw->bits &= ~CCW_WAIT4END;
413 } else {
414 idx = 0;
415 }
416
417 if (direction == DMA_NONE) {
418 ccw = &mxs_chan->ccw[idx++];
419 pio = (u32 *) sgl;
420
421 for (j = 0; j < sg_len;)
422 ccw->pio_words[j++] = *pio++;
423
424 ccw->bits = 0;
425 ccw->bits |= CCW_IRQ;
426 ccw->bits |= CCW_DEC_SEM;
427 ccw->bits |= CCW_WAIT4END;
428 ccw->bits |= CCW_HALT_ON_TERM;
429 ccw->bits |= CCW_TERM_FLUSH;
430 ccw->bits |= BF_CCW(sg_len, PIO_NUM);
431 ccw->bits |= BF_CCW(MXS_DMA_CMD_NO_XFER, COMMAND);
432 } else {
433 for_each_sg(sgl, sg, sg_len, i) {
434 if (sg->length > MAX_XFER_BYTES) {
435 dev_err(mxs_dma->dma_device.dev, "maximum bytes for sg entry exceeded: %d > %d\n",
436 sg->length, MAX_XFER_BYTES);
437 goto err_out;
438 }
439
440 ccw = &mxs_chan->ccw[idx++];
441
442 ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * idx;
443 ccw->bufaddr = sg->dma_address;
444 ccw->xfer_bytes = sg->length;
445
446 ccw->bits = 0;
447 ccw->bits |= CCW_CHAIN;
448 ccw->bits |= CCW_HALT_ON_TERM;
449 ccw->bits |= CCW_TERM_FLUSH;
450 ccw->bits |= BF_CCW(direction == DMA_FROM_DEVICE ?
451 MXS_DMA_CMD_WRITE : MXS_DMA_CMD_READ,
452 COMMAND);
453
454 if (i + 1 == sg_len) {
455 ccw->bits &= ~CCW_CHAIN;
456 ccw->bits |= CCW_IRQ;
457 ccw->bits |= CCW_DEC_SEM;
458 ccw->bits |= CCW_WAIT4END;
459 }
460 }
461 }
462
463 return &mxs_chan->desc;
464
465 err_out:
466 mxs_chan->status = DMA_ERROR;
467 return NULL;
468 }
469
470 static struct dma_async_tx_descriptor *mxs_dma_prep_dma_cyclic(
471 struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
472 size_t period_len, enum dma_data_direction direction)
473 {
474 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
475 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
476 int num_periods = buf_len / period_len;
477 int i = 0, buf = 0;
478
479 if (mxs_chan->status == DMA_IN_PROGRESS)
480 return NULL;
481
482 mxs_chan->status = DMA_IN_PROGRESS;
483 mxs_chan->flags |= MXS_DMA_SG_LOOP;
484
485 if (num_periods > NUM_CCW) {
486 dev_err(mxs_dma->dma_device.dev,
487 "maximum number of sg exceeded: %d > %d\n",
488 num_periods, NUM_CCW);
489 goto err_out;
490 }
491
492 if (period_len > MAX_XFER_BYTES) {
493 dev_err(mxs_dma->dma_device.dev,
494 "maximum period size exceeded: %d > %d\n",
495 period_len, MAX_XFER_BYTES);
496 goto err_out;
497 }
498
499 while (buf < buf_len) {
500 struct mxs_dma_ccw *ccw = &mxs_chan->ccw[i];
501
502 if (i + 1 == num_periods)
503 ccw->next = mxs_chan->ccw_phys;
504 else
505 ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * (i + 1);
506
507 ccw->bufaddr = dma_addr;
508 ccw->xfer_bytes = period_len;
509
510 ccw->bits = 0;
511 ccw->bits |= CCW_CHAIN;
512 ccw->bits |= CCW_IRQ;
513 ccw->bits |= CCW_HALT_ON_TERM;
514 ccw->bits |= CCW_TERM_FLUSH;
515 ccw->bits |= BF_CCW(direction == DMA_FROM_DEVICE ?
516 MXS_DMA_CMD_WRITE : MXS_DMA_CMD_READ, COMMAND);
517
518 dma_addr += period_len;
519 buf += period_len;
520
521 i++;
522 }
523
524 return &mxs_chan->desc;
525
526 err_out:
527 mxs_chan->status = DMA_ERROR;
528 return NULL;
529 }
530
531 static int mxs_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
532 unsigned long arg)
533 {
534 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
535 int ret = 0;
536
537 switch (cmd) {
538 case DMA_TERMINATE_ALL:
539 mxs_dma_disable_chan(mxs_chan);
540 mxs_dma_reset_chan(mxs_chan);
541 break;
542 case DMA_PAUSE:
543 mxs_dma_pause_chan(mxs_chan);
544 break;
545 case DMA_RESUME:
546 mxs_dma_resume_chan(mxs_chan);
547 break;
548 default:
549 ret = -ENOSYS;
550 }
551
552 return ret;
553 }
554
555 static enum dma_status mxs_dma_tx_status(struct dma_chan *chan,
556 dma_cookie_t cookie, struct dma_tx_state *txstate)
557 {
558 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
559 dma_cookie_t last_used;
560
561 last_used = chan->cookie;
562 dma_set_tx_state(txstate, mxs_chan->last_completed, last_used, 0);
563
564 return mxs_chan->status;
565 }
566
567 static void mxs_dma_issue_pending(struct dma_chan *chan)
568 {
569 /*
570 * Nothing to do. We only have a single descriptor.
571 */
572 }
573
574 static int __init mxs_dma_init(struct mxs_dma_engine *mxs_dma)
575 {
576 int ret;
577
578 ret = clk_enable(mxs_dma->clk);
579 if (ret)
580 goto err_out;
581
582 ret = mxs_reset_block(mxs_dma->base);
583 if (ret)
584 goto err_out;
585
586 /* only major version matters */
587 mxs_dma->version = readl(mxs_dma->base +
588 ((mxs_dma->dev_id == MXS_DMA_APBX) ?
589 HW_APBX_VERSION : HW_APBH_VERSION)) >>
590 BP_APBHX_VERSION_MAJOR;
591
592 /* enable apbh burst */
593 if (dma_is_apbh()) {
594 writel(BM_APBH_CTRL0_APB_BURST_EN,
595 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
596 writel(BM_APBH_CTRL0_APB_BURST8_EN,
597 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
598 }
599
600 /* enable irq for all the channels */
601 writel(MXS_DMA_CHANNELS_MASK << MXS_DMA_CHANNELS,
602 mxs_dma->base + HW_APBHX_CTRL1 + MXS_SET_ADDR);
603
604 clk_disable(mxs_dma->clk);
605
606 return 0;
607
608 err_out:
609 return ret;
610 }
611
612 static int __init mxs_dma_probe(struct platform_device *pdev)
613 {
614 const struct platform_device_id *id_entry =
615 platform_get_device_id(pdev);
616 struct mxs_dma_engine *mxs_dma;
617 struct resource *iores;
618 int ret, i;
619
620 mxs_dma = kzalloc(sizeof(*mxs_dma), GFP_KERNEL);
621 if (!mxs_dma)
622 return -ENOMEM;
623
624 mxs_dma->dev_id = id_entry->driver_data;
625
626 iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
627
628 if (!request_mem_region(iores->start, resource_size(iores),
629 pdev->name)) {
630 ret = -EBUSY;
631 goto err_request_region;
632 }
633
634 mxs_dma->base = ioremap(iores->start, resource_size(iores));
635 if (!mxs_dma->base) {
636 ret = -ENOMEM;
637 goto err_ioremap;
638 }
639
640 mxs_dma->clk = clk_get(&pdev->dev, NULL);
641 if (IS_ERR(mxs_dma->clk)) {
642 ret = PTR_ERR(mxs_dma->clk);
643 goto err_clk;
644 }
645
646 dma_cap_set(DMA_SLAVE, mxs_dma->dma_device.cap_mask);
647 dma_cap_set(DMA_CYCLIC, mxs_dma->dma_device.cap_mask);
648
649 INIT_LIST_HEAD(&mxs_dma->dma_device.channels);
650
651 /* Initialize channel parameters */
652 for (i = 0; i < MXS_DMA_CHANNELS; i++) {
653 struct mxs_dma_chan *mxs_chan = &mxs_dma->mxs_chans[i];
654
655 mxs_chan->mxs_dma = mxs_dma;
656 mxs_chan->chan.device = &mxs_dma->dma_device;
657
658 tasklet_init(&mxs_chan->tasklet, mxs_dma_tasklet,
659 (unsigned long) mxs_chan);
660
661
662 /* Add the channel to mxs_chan list */
663 list_add_tail(&mxs_chan->chan.device_node,
664 &mxs_dma->dma_device.channels);
665 }
666
667 ret = mxs_dma_init(mxs_dma);
668 if (ret)
669 goto err_init;
670
671 mxs_dma->dma_device.dev = &pdev->dev;
672
673 /* mxs_dma gets 65535 bytes maximum sg size */
674 mxs_dma->dma_device.dev->dma_parms = &mxs_dma->dma_parms;
675 dma_set_max_seg_size(mxs_dma->dma_device.dev, MAX_XFER_BYTES);
676
677 mxs_dma->dma_device.device_alloc_chan_resources = mxs_dma_alloc_chan_resources;
678 mxs_dma->dma_device.device_free_chan_resources = mxs_dma_free_chan_resources;
679 mxs_dma->dma_device.device_tx_status = mxs_dma_tx_status;
680 mxs_dma->dma_device.device_prep_slave_sg = mxs_dma_prep_slave_sg;
681 mxs_dma->dma_device.device_prep_dma_cyclic = mxs_dma_prep_dma_cyclic;
682 mxs_dma->dma_device.device_control = mxs_dma_control;
683 mxs_dma->dma_device.device_issue_pending = mxs_dma_issue_pending;
684
685 ret = dma_async_device_register(&mxs_dma->dma_device);
686 if (ret) {
687 dev_err(mxs_dma->dma_device.dev, "unable to register\n");
688 goto err_init;
689 }
690
691 dev_info(mxs_dma->dma_device.dev, "initialized\n");
692
693 return 0;
694
695 err_init:
696 clk_put(mxs_dma->clk);
697 err_clk:
698 iounmap(mxs_dma->base);
699 err_ioremap:
700 release_mem_region(iores->start, resource_size(iores));
701 err_request_region:
702 kfree(mxs_dma);
703 return ret;
704 }
705
706 static struct platform_device_id mxs_dma_type[] = {
707 {
708 .name = "mxs-dma-apbh",
709 .driver_data = MXS_DMA_APBH,
710 }, {
711 .name = "mxs-dma-apbx",
712 .driver_data = MXS_DMA_APBX,
713 }, {
714 /* end of list */
715 }
716 };
717
718 static struct platform_driver mxs_dma_driver = {
719 .driver = {
720 .name = "mxs-dma",
721 },
722 .id_table = mxs_dma_type,
723 };
724
725 static int __init mxs_dma_module_init(void)
726 {
727 return platform_driver_probe(&mxs_dma_driver, mxs_dma_probe);
728 }
729 subsys_initcall(mxs_dma_module_init);
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree