Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
[pandora-kernel.git] / drivers / dma / coh901318.c
1 /*
2  * driver/dma/coh901318.c
3  *
4  * Copyright (C) 2007-2009 ST-Ericsson
5  * License terms: GNU General Public License (GPL) version 2
6  * DMA driver for COH 901 318
7  * Author: Per Friden <per.friden@stericsson.com>
8  */
9
10 #include <linux/init.h>
11 #include <linux/module.h>
12 #include <linux/kernel.h> /* printk() */
13 #include <linux/fs.h> /* everything... */
14 #include <linux/scatterlist.h>
15 #include <linux/slab.h> /* kmalloc() */
16 #include <linux/dmaengine.h>
17 #include <linux/platform_device.h>
18 #include <linux/device.h>
19 #include <linux/irqreturn.h>
20 #include <linux/interrupt.h>
21 #include <linux/io.h>
22 #include <linux/uaccess.h>
23 #include <linux/debugfs.h>
24 #include <mach/coh901318.h>
25
26 #include "coh901318_lli.h"
27
28 #define COHC_2_DEV(cohc) (&cohc->chan.dev->device)
29
30 #ifdef VERBOSE_DEBUG
31 #define COH_DBG(x) ({ if (1) x; 0; })
32 #else
33 #define COH_DBG(x) ({ if (0) x; 0; })
34 #endif
35
36 struct coh901318_desc {
37         struct dma_async_tx_descriptor desc;
38         struct list_head node;
39         struct scatterlist *sg;
40         unsigned int sg_len;
41         struct coh901318_lli *lli;
42         enum dma_data_direction dir;
43         unsigned long flags;
44 };
45
46 struct coh901318_base {
47         struct device *dev;
48         void __iomem *virtbase;
49         struct coh901318_pool pool;
50         struct powersave pm;
51         struct dma_device dma_slave;
52         struct dma_device dma_memcpy;
53         struct coh901318_chan *chans;
54         struct coh901318_platform *platform;
55 };
56
57 struct coh901318_chan {
58         spinlock_t lock;
59         int allocated;
60         int completed;
61         int id;
62         int stopped;
63
64         struct work_struct free_work;
65         struct dma_chan chan;
66
67         struct tasklet_struct tasklet;
68
69         struct list_head active;
70         struct list_head queue;
71         struct list_head free;
72
73         unsigned long nbr_active_done;
74         unsigned long busy;
75
76         u32 runtime_addr;
77         u32 runtime_ctrl;
78
79         struct coh901318_base *base;
80 };
81
82 static void coh901318_list_print(struct coh901318_chan *cohc,
83                                  struct coh901318_lli *lli)
84 {
85         struct coh901318_lli *l = lli;
86         int i = 0;
87
88         while (l) {
89                 dev_vdbg(COHC_2_DEV(cohc), "i %d, lli %p, ctrl 0x%x, src 0x%x"
90                          ", dst 0x%x, link 0x%x virt_link_addr 0x%p\n",
91                          i, l, l->control, l->src_addr, l->dst_addr,
92                          l->link_addr, l->virt_link_addr);
93                 i++;
94                 l = l->virt_link_addr;
95         }
96 }
97
98 #ifdef CONFIG_DEBUG_FS
99
100 #define COH901318_DEBUGFS_ASSIGN(x, y) (x = y)
101
102 static struct coh901318_base *debugfs_dma_base;
103 static struct dentry *dma_dentry;
104
105 static int coh901318_debugfs_open(struct inode *inode, struct file *file)
106 {
107
108         file->private_data = inode->i_private;
109         return 0;
110 }
111
112 static int coh901318_debugfs_read(struct file *file, char __user *buf,
113                                   size_t count, loff_t *f_pos)
114 {
115         u64 started_channels = debugfs_dma_base->pm.started_channels;
116         int pool_count = debugfs_dma_base->pool.debugfs_pool_counter;
117         int i;
118         int ret = 0;
119         char *dev_buf;
120         char *tmp;
121         int dev_size;
122
123         dev_buf = kmalloc(4*1024, GFP_KERNEL);
124         if (dev_buf == NULL)
125                 goto err_kmalloc;
126         tmp = dev_buf;
127
128         tmp += sprintf(tmp, "DMA -- enabled dma channels\n");
129
130         for (i = 0; i < debugfs_dma_base->platform->max_channels; i++)
131                 if (started_channels & (1 << i))
132                         tmp += sprintf(tmp, "channel %d\n", i);
133
134         tmp += sprintf(tmp, "Pool alloc nbr %d\n", pool_count);
135         dev_size = tmp  - dev_buf;
136
137         /* No more to read if offset != 0 */
138         if (*f_pos > dev_size)
139                 goto out;
140
141         if (count > dev_size - *f_pos)
142                 count = dev_size - *f_pos;
143
144         if (copy_to_user(buf, dev_buf + *f_pos, count))
145                 ret = -EINVAL;
146         ret = count;
147         *f_pos += count;
148
149  out:
150         kfree(dev_buf);
151         return ret;
152
153  err_kmalloc:
154         return 0;
155 }
156
157 static const struct file_operations coh901318_debugfs_status_operations = {
158         .owner          = THIS_MODULE,
159         .open           = coh901318_debugfs_open,
160         .read           = coh901318_debugfs_read,
161         .llseek         = default_llseek,
162 };
163
164
165 static int __init init_coh901318_debugfs(void)
166 {
167
168         dma_dentry = debugfs_create_dir("dma", NULL);
169
170         (void) debugfs_create_file("status",
171                                    S_IFREG | S_IRUGO,
172                                    dma_dentry, NULL,
173                                    &coh901318_debugfs_status_operations);
174         return 0;
175 }
176
177 static void __exit exit_coh901318_debugfs(void)
178 {
179         debugfs_remove_recursive(dma_dentry);
180 }
181
182 module_init(init_coh901318_debugfs);
183 module_exit(exit_coh901318_debugfs);
184 #else
185
186 #define COH901318_DEBUGFS_ASSIGN(x, y)
187
188 #endif /* CONFIG_DEBUG_FS */
189
190 static inline struct coh901318_chan *to_coh901318_chan(struct dma_chan *chan)
191 {
192         return container_of(chan, struct coh901318_chan, chan);
193 }
194
195 static inline dma_addr_t
196 cohc_dev_addr(struct coh901318_chan *cohc)
197 {
198         /* Runtime supplied address will take precedence */
199         if (cohc->runtime_addr)
200                 return cohc->runtime_addr;
201         return cohc->base->platform->chan_conf[cohc->id].dev_addr;
202 }
203
204 static inline const struct coh901318_params *
205 cohc_chan_param(struct coh901318_chan *cohc)
206 {
207         return &cohc->base->platform->chan_conf[cohc->id].param;
208 }
209
210 static inline const struct coh_dma_channel *
211 cohc_chan_conf(struct coh901318_chan *cohc)
212 {
213         return &cohc->base->platform->chan_conf[cohc->id];
214 }
215
216 static void enable_powersave(struct coh901318_chan *cohc)
217 {
218         unsigned long flags;
219         struct powersave *pm = &cohc->base->pm;
220
221         spin_lock_irqsave(&pm->lock, flags);
222
223         pm->started_channels &= ~(1ULL << cohc->id);
224
225         if (!pm->started_channels) {
226                 /* DMA no longer intends to access memory */
227                 cohc->base->platform->access_memory_state(cohc->base->dev,
228                                                           false);
229         }
230
231         spin_unlock_irqrestore(&pm->lock, flags);
232 }
233 static void disable_powersave(struct coh901318_chan *cohc)
234 {
235         unsigned long flags;
236         struct powersave *pm = &cohc->base->pm;
237
238         spin_lock_irqsave(&pm->lock, flags);
239
240         if (!pm->started_channels) {
241                 /* DMA intends to access memory */
242                 cohc->base->platform->access_memory_state(cohc->base->dev,
243                                                           true);
244         }
245
246         pm->started_channels |= (1ULL << cohc->id);
247
248         spin_unlock_irqrestore(&pm->lock, flags);
249 }
250
251 static inline int coh901318_set_ctrl(struct coh901318_chan *cohc, u32 control)
252 {
253         int channel = cohc->id;
254         void __iomem *virtbase = cohc->base->virtbase;
255
256         writel(control,
257                virtbase + COH901318_CX_CTRL +
258                COH901318_CX_CTRL_SPACING * channel);
259         return 0;
260 }
261
262 static inline int coh901318_set_conf(struct coh901318_chan *cohc, u32 conf)
263 {
264         int channel = cohc->id;
265         void __iomem *virtbase = cohc->base->virtbase;
266
267         writel(conf,
268                virtbase + COH901318_CX_CFG +
269                COH901318_CX_CFG_SPACING*channel);
270         return 0;
271 }
272
273
274 static int coh901318_start(struct coh901318_chan *cohc)
275 {
276         u32 val;
277         int channel = cohc->id;
278         void __iomem *virtbase = cohc->base->virtbase;
279
280         disable_powersave(cohc);
281
282         val = readl(virtbase + COH901318_CX_CFG +
283                     COH901318_CX_CFG_SPACING * channel);
284
285         /* Enable channel */
286         val |= COH901318_CX_CFG_CH_ENABLE;
287         writel(val, virtbase + COH901318_CX_CFG +
288                COH901318_CX_CFG_SPACING * channel);
289
290         return 0;
291 }
292
293 static int coh901318_prep_linked_list(struct coh901318_chan *cohc,
294                                       struct coh901318_lli *lli)
295 {
296         int channel = cohc->id;
297         void __iomem *virtbase = cohc->base->virtbase;
298
299         BUG_ON(readl(virtbase + COH901318_CX_STAT +
300                      COH901318_CX_STAT_SPACING*channel) &
301                COH901318_CX_STAT_ACTIVE);
302
303         writel(lli->src_addr,
304                virtbase + COH901318_CX_SRC_ADDR +
305                COH901318_CX_SRC_ADDR_SPACING * channel);
306
307         writel(lli->dst_addr, virtbase +
308                COH901318_CX_DST_ADDR +
309                COH901318_CX_DST_ADDR_SPACING * channel);
310
311         writel(lli->link_addr, virtbase + COH901318_CX_LNK_ADDR +
312                COH901318_CX_LNK_ADDR_SPACING * channel);
313
314         writel(lli->control, virtbase + COH901318_CX_CTRL +
315                COH901318_CX_CTRL_SPACING * channel);
316
317         return 0;
318 }
319 static dma_cookie_t
320 coh901318_assign_cookie(struct coh901318_chan *cohc,
321                         struct coh901318_desc *cohd)
322 {
323         dma_cookie_t cookie = cohc->chan.cookie;
324
325         if (++cookie < 0)
326                 cookie = 1;
327
328         cohc->chan.cookie = cookie;
329         cohd->desc.cookie = cookie;
330
331         return cookie;
332 }
333
334 static struct coh901318_desc *
335 coh901318_desc_get(struct coh901318_chan *cohc)
336 {
337         struct coh901318_desc *desc;
338
339         if (list_empty(&cohc->free)) {
340                 /* alloc new desc because we're out of used ones
341                  * TODO: alloc a pile of descs instead of just one,
342                  * avoid many small allocations.
343                  */
344                 desc = kzalloc(sizeof(struct coh901318_desc), GFP_NOWAIT);
345                 if (desc == NULL)
346                         goto out;
347                 INIT_LIST_HEAD(&desc->node);
348                 dma_async_tx_descriptor_init(&desc->desc, &cohc->chan);
349         } else {
350                 /* Reuse an old desc. */
351                 desc = list_first_entry(&cohc->free,
352                                         struct coh901318_desc,
353                                         node);
354                 list_del(&desc->node);
355                 /* Initialize it a bit so it's not insane */
356                 desc->sg = NULL;
357                 desc->sg_len = 0;
358                 desc->desc.callback = NULL;
359                 desc->desc.callback_param = NULL;
360         }
361
362  out:
363         return desc;
364 }
365
366 static void
367 coh901318_desc_free(struct coh901318_chan *cohc, struct coh901318_desc *cohd)
368 {
369         list_add_tail(&cohd->node, &cohc->free);
370 }
371
372 /* call with irq lock held */
373 static void
374 coh901318_desc_submit(struct coh901318_chan *cohc, struct coh901318_desc *desc)
375 {
376         list_add_tail(&desc->node, &cohc->active);
377 }
378
379 static struct coh901318_desc *
380 coh901318_first_active_get(struct coh901318_chan *cohc)
381 {
382         struct coh901318_desc *d;
383
384         if (list_empty(&cohc->active))
385                 return NULL;
386
387         d = list_first_entry(&cohc->active,
388                              struct coh901318_desc,
389                              node);
390         return d;
391 }
392
393 static void
394 coh901318_desc_remove(struct coh901318_desc *cohd)
395 {
396         list_del(&cohd->node);
397 }
398
399 static void
400 coh901318_desc_queue(struct coh901318_chan *cohc, struct coh901318_desc *desc)
401 {
402         list_add_tail(&desc->node, &cohc->queue);
403 }
404
405 static struct coh901318_desc *
406 coh901318_first_queued(struct coh901318_chan *cohc)
407 {
408         struct coh901318_desc *d;
409
410         if (list_empty(&cohc->queue))
411                 return NULL;
412
413         d = list_first_entry(&cohc->queue,
414                              struct coh901318_desc,
415                              node);
416         return d;
417 }
418
419 static inline u32 coh901318_get_bytes_in_lli(struct coh901318_lli *in_lli)
420 {
421         struct coh901318_lli *lli = in_lli;
422         u32 bytes = 0;
423
424         while (lli) {
425                 bytes += lli->control & COH901318_CX_CTRL_TC_VALUE_MASK;
426                 lli = lli->virt_link_addr;
427         }
428         return bytes;
429 }
430
431 /*
432  * Get the number of bytes left to transfer on this channel,
433  * it is unwise to call this before stopping the channel for
434  * absolute measures, but for a rough guess you can still call
435  * it.
436  */
437 static u32 coh901318_get_bytes_left(struct dma_chan *chan)
438 {
439         struct coh901318_chan *cohc = to_coh901318_chan(chan);
440         struct coh901318_desc *cohd;
441         struct list_head *pos;
442         unsigned long flags;
443         u32 left = 0;
444         int i = 0;
445
446         spin_lock_irqsave(&cohc->lock, flags);
447
448         /*
449          * If there are many queued jobs, we iterate and add the
450          * size of them all. We take a special look on the first
451          * job though, since it is probably active.
452          */
453         list_for_each(pos, &cohc->active) {
454                 /*
455                  * The first job in the list will be working on the
456                  * hardware. The job can be stopped but still active,
457                  * so that the transfer counter is somewhere inside
458                  * the buffer.
459                  */
460                 cohd = list_entry(pos, struct coh901318_desc, node);
461
462                 if (i == 0) {
463                         struct coh901318_lli *lli;
464                         dma_addr_t ladd;
465
466                         /* Read current transfer count value */
467                         left = readl(cohc->base->virtbase +
468                                      COH901318_CX_CTRL +
469                                      COH901318_CX_CTRL_SPACING * cohc->id) &
470                                 COH901318_CX_CTRL_TC_VALUE_MASK;
471
472                         /* See if the transfer is linked... */
473                         ladd = readl(cohc->base->virtbase +
474                                      COH901318_CX_LNK_ADDR +
475                                      COH901318_CX_LNK_ADDR_SPACING *
476                                      cohc->id) &
477                                 ~COH901318_CX_LNK_LINK_IMMEDIATE;
478                         /* Single transaction */
479                         if (!ladd)
480                                 continue;
481
482                         /*
483                          * Linked transaction, follow the lli, find the
484                          * currently processing lli, and proceed to the next
485                          */
486                         lli = cohd->lli;
487                         while (lli && lli->link_addr != ladd)
488                                 lli = lli->virt_link_addr;
489
490                         if (lli)
491                                 lli = lli->virt_link_addr;
492
493                         /*
494                          * Follow remaining lli links around to count the total
495                          * number of bytes left
496                          */
497                         left += coh901318_get_bytes_in_lli(lli);
498                 } else {
499                         left += coh901318_get_bytes_in_lli(cohd->lli);
500                 }
501                 i++;
502         }
503
504         /* Also count bytes in the queued jobs */
505         list_for_each(pos, &cohc->queue) {
506                 cohd = list_entry(pos, struct coh901318_desc, node);
507                 left += coh901318_get_bytes_in_lli(cohd->lli);
508         }
509
510         spin_unlock_irqrestore(&cohc->lock, flags);
511
512         return left;
513 }
514
515 /*
516  * Pauses a transfer without losing data. Enables power save.
517  * Use this function in conjunction with coh901318_resume.
518  */
519 static void coh901318_pause(struct dma_chan *chan)
520 {
521         u32 val;
522         unsigned long flags;
523         struct coh901318_chan *cohc = to_coh901318_chan(chan);
524         int channel = cohc->id;
525         void __iomem *virtbase = cohc->base->virtbase;
526
527         spin_lock_irqsave(&cohc->lock, flags);
528
529         /* Disable channel in HW */
530         val = readl(virtbase + COH901318_CX_CFG +
531                     COH901318_CX_CFG_SPACING * channel);
532
533         /* Stopping infinite transfer */
534         if ((val & COH901318_CX_CTRL_TC_ENABLE) == 0 &&
535             (val & COH901318_CX_CFG_CH_ENABLE))
536                 cohc->stopped = 1;
537
538
539         val &= ~COH901318_CX_CFG_CH_ENABLE;
540         /* Enable twice, HW bug work around */
541         writel(val, virtbase + COH901318_CX_CFG +
542                COH901318_CX_CFG_SPACING * channel);
543         writel(val, virtbase + COH901318_CX_CFG +
544                COH901318_CX_CFG_SPACING * channel);
545
546         /* Spin-wait for it to actually go inactive */
547         while (readl(virtbase + COH901318_CX_STAT+COH901318_CX_STAT_SPACING *
548                      channel) & COH901318_CX_STAT_ACTIVE)
549                 cpu_relax();
550
551         /* Check if we stopped an active job */
552         if ((readl(virtbase + COH901318_CX_CTRL+COH901318_CX_CTRL_SPACING *
553                    channel) & COH901318_CX_CTRL_TC_VALUE_MASK) > 0)
554                 cohc->stopped = 1;
555
556         enable_powersave(cohc);
557
558         spin_unlock_irqrestore(&cohc->lock, flags);
559 }
560
561 /* Resumes a transfer that has been stopped via 300_dma_stop(..).
562    Power save is handled.
563 */
564 static void coh901318_resume(struct dma_chan *chan)
565 {
566         u32 val;
567         unsigned long flags;
568         struct coh901318_chan *cohc = to_coh901318_chan(chan);
569         int channel = cohc->id;
570
571         spin_lock_irqsave(&cohc->lock, flags);
572
573         disable_powersave(cohc);
574
575         if (cohc->stopped) {
576                 /* Enable channel in HW */
577                 val = readl(cohc->base->virtbase + COH901318_CX_CFG +
578                             COH901318_CX_CFG_SPACING * channel);
579
580                 val |= COH901318_CX_CFG_CH_ENABLE;
581
582                 writel(val, cohc->base->virtbase + COH901318_CX_CFG +
583                        COH901318_CX_CFG_SPACING*channel);
584
585                 cohc->stopped = 0;
586         }
587
588         spin_unlock_irqrestore(&cohc->lock, flags);
589 }
590
591 bool coh901318_filter_id(struct dma_chan *chan, void *chan_id)
592 {
593         unsigned int ch_nr = (unsigned int) chan_id;
594
595         if (ch_nr == to_coh901318_chan(chan)->id)
596                 return true;
597
598         return false;
599 }
600 EXPORT_SYMBOL(coh901318_filter_id);
601
602 /*
603  * DMA channel allocation
604  */
605 static int coh901318_config(struct coh901318_chan *cohc,
606                             struct coh901318_params *param)
607 {
608         unsigned long flags;
609         const struct coh901318_params *p;
610         int channel = cohc->id;
611         void __iomem *virtbase = cohc->base->virtbase;
612
613         spin_lock_irqsave(&cohc->lock, flags);
614
615         if (param)
616                 p = param;
617         else
618                 p = &cohc->base->platform->chan_conf[channel].param;
619
620         /* Clear any pending BE or TC interrupt */
621         if (channel < 32) {
622                 writel(1 << channel, virtbase + COH901318_BE_INT_CLEAR1);
623                 writel(1 << channel, virtbase + COH901318_TC_INT_CLEAR1);
624         } else {
625                 writel(1 << (channel - 32), virtbase +
626                        COH901318_BE_INT_CLEAR2);
627                 writel(1 << (channel - 32), virtbase +
628                        COH901318_TC_INT_CLEAR2);
629         }
630
631         coh901318_set_conf(cohc, p->config);
632         coh901318_set_ctrl(cohc, p->ctrl_lli_last);
633
634         spin_unlock_irqrestore(&cohc->lock, flags);
635
636         return 0;
637 }
638
639 /* must lock when calling this function
640  * start queued jobs, if any
641  * TODO: start all queued jobs in one go
642  *
643  * Returns descriptor if queued job is started otherwise NULL.
644  * If the queue is empty NULL is returned.
645  */
646 static struct coh901318_desc *coh901318_queue_start(struct coh901318_chan *cohc)
647 {
648         struct coh901318_desc *cohd;
649
650         /*
651          * start queued jobs, if any
652          * TODO: transmit all queued jobs in one go
653          */
654         cohd = coh901318_first_queued(cohc);
655
656         if (cohd != NULL) {
657                 /* Remove from queue */
658                 coh901318_desc_remove(cohd);
659                 /* initiate DMA job */
660                 cohc->busy = 1;
661
662                 coh901318_desc_submit(cohc, cohd);
663
664                 coh901318_prep_linked_list(cohc, cohd->lli);
665
666                 /* start dma job on this channel */
667                 coh901318_start(cohc);
668
669         }
670
671         return cohd;
672 }
673
674 /*
675  * This tasklet is called from the interrupt handler to
676  * handle each descriptor (DMA job) that is sent to a channel.
677  */
678 static void dma_tasklet(unsigned long data)
679 {
680         struct coh901318_chan *cohc = (struct coh901318_chan *) data;
681         struct coh901318_desc *cohd_fin;
682         unsigned long flags;
683         dma_async_tx_callback callback;
684         void *callback_param;
685
686         dev_vdbg(COHC_2_DEV(cohc), "[%s] chan_id %d"
687                  " nbr_active_done %ld\n", __func__,
688                  cohc->id, cohc->nbr_active_done);
689
690         spin_lock_irqsave(&cohc->lock, flags);
691
692         /* get first active descriptor entry from list */
693         cohd_fin = coh901318_first_active_get(cohc);
694
695         if (cohd_fin == NULL)
696                 goto err;
697
698         /* locate callback to client */
699         callback = cohd_fin->desc.callback;
700         callback_param = cohd_fin->desc.callback_param;
701
702         /* sign this job as completed on the channel */
703         cohc->completed = cohd_fin->desc.cookie;
704
705         /* release the lli allocation and remove the descriptor */
706         coh901318_lli_free(&cohc->base->pool, &cohd_fin->lli);
707
708         /* return desc to free-list */
709         coh901318_desc_remove(cohd_fin);
710         coh901318_desc_free(cohc, cohd_fin);
711
712         spin_unlock_irqrestore(&cohc->lock, flags);
713
714         /* Call the callback when we're done */
715         if (callback)
716                 callback(callback_param);
717
718         spin_lock_irqsave(&cohc->lock, flags);
719
720         /*
721          * If another interrupt fired while the tasklet was scheduling,
722          * we don't get called twice, so we have this number of active
723          * counter that keep track of the number of IRQs expected to
724          * be handled for this channel. If there happen to be more than
725          * one IRQ to be ack:ed, we simply schedule this tasklet again.
726          */
727         cohc->nbr_active_done--;
728         if (cohc->nbr_active_done) {
729                 dev_dbg(COHC_2_DEV(cohc), "scheduling tasklet again, new IRQs "
730                         "came in while we were scheduling this tasklet\n");
731                 if (cohc_chan_conf(cohc)->priority_high)
732                         tasklet_hi_schedule(&cohc->tasklet);
733                 else
734                         tasklet_schedule(&cohc->tasklet);
735         }
736
737         spin_unlock_irqrestore(&cohc->lock, flags);
738
739         return;
740
741  err:
742         spin_unlock_irqrestore(&cohc->lock, flags);
743         dev_err(COHC_2_DEV(cohc), "[%s] No active dma desc\n", __func__);
744 }
745
746
747 /* called from interrupt context */
748 static void dma_tc_handle(struct coh901318_chan *cohc)
749 {
750         /*
751          * If the channel is not allocated, then we shouldn't have
752          * any TC interrupts on it.
753          */
754         if (!cohc->allocated) {
755                 dev_err(COHC_2_DEV(cohc), "spurious interrupt from "
756                         "unallocated channel\n");
757                 return;
758         }
759
760         spin_lock(&cohc->lock);
761
762         /*
763          * When we reach this point, at least one queue item
764          * should have been moved over from cohc->queue to
765          * cohc->active and run to completion, that is why we're
766          * getting a terminal count interrupt is it not?
767          * If you get this BUG() the most probable cause is that
768          * the individual nodes in the lli chain have IRQ enabled,
769          * so check your platform config for lli chain ctrl.
770          */
771         BUG_ON(list_empty(&cohc->active));
772
773         cohc->nbr_active_done++;
774
775         /*
776          * This attempt to take a job from cohc->queue, put it
777          * into cohc->active and start it.
778          */
779         if (coh901318_queue_start(cohc) == NULL)
780                 cohc->busy = 0;
781
782         spin_unlock(&cohc->lock);
783
784         /*
785          * This tasklet will remove items from cohc->active
786          * and thus terminates them.
787          */
788         if (cohc_chan_conf(cohc)->priority_high)
789                 tasklet_hi_schedule(&cohc->tasklet);
790         else
791                 tasklet_schedule(&cohc->tasklet);
792 }
793
794
795 static irqreturn_t dma_irq_handler(int irq, void *dev_id)
796 {
797         u32 status1;
798         u32 status2;
799         int i;
800         int ch;
801         struct coh901318_base *base  = dev_id;
802         struct coh901318_chan *cohc;
803         void __iomem *virtbase = base->virtbase;
804
805         status1 = readl(virtbase + COH901318_INT_STATUS1);
806         status2 = readl(virtbase + COH901318_INT_STATUS2);
807
808         if (unlikely(status1 == 0 && status2 == 0)) {
809                 dev_warn(base->dev, "spurious DMA IRQ from no channel!\n");
810                 return IRQ_HANDLED;
811         }
812
813         /* TODO: consider handle IRQ in tasklet here to
814          *       minimize interrupt latency */
815
816         /* Check the first 32 DMA channels for IRQ */
817         while (status1) {
818                 /* Find first bit set, return as a number. */
819                 i = ffs(status1) - 1;
820                 ch = i;
821
822                 cohc = &base->chans[ch];
823                 spin_lock(&cohc->lock);
824
825                 /* Mask off this bit */
826                 status1 &= ~(1 << i);
827                 /* Check the individual channel bits */
828                 if (test_bit(i, virtbase + COH901318_BE_INT_STATUS1)) {
829                         dev_crit(COHC_2_DEV(cohc),
830                                  "DMA bus error on channel %d!\n", ch);
831                         BUG_ON(1);
832                         /* Clear BE interrupt */
833                         __set_bit(i, virtbase + COH901318_BE_INT_CLEAR1);
834                 } else {
835                         /* Caused by TC, really? */
836                         if (unlikely(!test_bit(i, virtbase +
837                                                COH901318_TC_INT_STATUS1))) {
838                                 dev_warn(COHC_2_DEV(cohc),
839                                          "ignoring interrupt not caused by terminal count on channel %d\n", ch);
840                                 /* Clear TC interrupt */
841                                 BUG_ON(1);
842                                 __set_bit(i, virtbase + COH901318_TC_INT_CLEAR1);
843                         } else {
844                                 /* Enable powersave if transfer has finished */
845                                 if (!(readl(virtbase + COH901318_CX_STAT +
846                                             COH901318_CX_STAT_SPACING*ch) &
847                                       COH901318_CX_STAT_ENABLED)) {
848                                         enable_powersave(cohc);
849                                 }
850
851                                 /* Must clear TC interrupt before calling
852                                  * dma_tc_handle
853                                  * in case tc_handle initiate a new dma job
854                                  */
855                                 __set_bit(i, virtbase + COH901318_TC_INT_CLEAR1);
856
857                                 dma_tc_handle(cohc);
858                         }
859                 }
860                 spin_unlock(&cohc->lock);
861         }
862
863         /* Check the remaining 32 DMA channels for IRQ */
864         while (status2) {
865                 /* Find first bit set, return as a number. */
866                 i = ffs(status2) - 1;
867                 ch = i + 32;
868                 cohc = &base->chans[ch];
869                 spin_lock(&cohc->lock);
870
871                 /* Mask off this bit */
872                 status2 &= ~(1 << i);
873                 /* Check the individual channel bits */
874                 if (test_bit(i, virtbase + COH901318_BE_INT_STATUS2)) {
875                         dev_crit(COHC_2_DEV(cohc),
876                                  "DMA bus error on channel %d!\n", ch);
877                         /* Clear BE interrupt */
878                         BUG_ON(1);
879                         __set_bit(i, virtbase + COH901318_BE_INT_CLEAR2);
880                 } else {
881                         /* Caused by TC, really? */
882                         if (unlikely(!test_bit(i, virtbase +
883                                                COH901318_TC_INT_STATUS2))) {
884                                 dev_warn(COHC_2_DEV(cohc),
885                                          "ignoring interrupt not caused by terminal count on channel %d\n", ch);
886                                 /* Clear TC interrupt */
887                                 __set_bit(i, virtbase + COH901318_TC_INT_CLEAR2);
888                                 BUG_ON(1);
889                         } else {
890                                 /* Enable powersave if transfer has finished */
891                                 if (!(readl(virtbase + COH901318_CX_STAT +
892                                             COH901318_CX_STAT_SPACING*ch) &
893                                       COH901318_CX_STAT_ENABLED)) {
894                                         enable_powersave(cohc);
895                                 }
896                                 /* Must clear TC interrupt before calling
897                                  * dma_tc_handle
898                                  * in case tc_handle initiate a new dma job
899                                  */
900                                 __set_bit(i, virtbase + COH901318_TC_INT_CLEAR2);
901
902                                 dma_tc_handle(cohc);
903                         }
904                 }
905                 spin_unlock(&cohc->lock);
906         }
907
908         return IRQ_HANDLED;
909 }
910
911 static int coh901318_alloc_chan_resources(struct dma_chan *chan)
912 {
913         struct coh901318_chan   *cohc = to_coh901318_chan(chan);
914         unsigned long flags;
915
916         dev_vdbg(COHC_2_DEV(cohc), "[%s] DMA channel %d\n",
917                  __func__, cohc->id);
918
919         if (chan->client_count > 1)
920                 return -EBUSY;
921
922         spin_lock_irqsave(&cohc->lock, flags);
923
924         coh901318_config(cohc, NULL);
925
926         cohc->allocated = 1;
927         cohc->completed = chan->cookie = 1;
928
929         spin_unlock_irqrestore(&cohc->lock, flags);
930
931         return 1;
932 }
933
934 static void
935 coh901318_free_chan_resources(struct dma_chan *chan)
936 {
937         struct coh901318_chan   *cohc = to_coh901318_chan(chan);
938         int channel = cohc->id;
939         unsigned long flags;
940
941         spin_lock_irqsave(&cohc->lock, flags);
942
943         /* Disable HW */
944         writel(0x00000000U, cohc->base->virtbase + COH901318_CX_CFG +
945                COH901318_CX_CFG_SPACING*channel);
946         writel(0x00000000U, cohc->base->virtbase + COH901318_CX_CTRL +
947                COH901318_CX_CTRL_SPACING*channel);
948
949         cohc->allocated = 0;
950
951         spin_unlock_irqrestore(&cohc->lock, flags);
952
953         chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
954 }
955
956
957 static dma_cookie_t
958 coh901318_tx_submit(struct dma_async_tx_descriptor *tx)
959 {
960         struct coh901318_desc *cohd = container_of(tx, struct coh901318_desc,
961                                                    desc);
962         struct coh901318_chan *cohc = to_coh901318_chan(tx->chan);
963         unsigned long flags;
964
965         spin_lock_irqsave(&cohc->lock, flags);
966
967         tx->cookie = coh901318_assign_cookie(cohc, cohd);
968
969         coh901318_desc_queue(cohc, cohd);
970
971         spin_unlock_irqrestore(&cohc->lock, flags);
972
973         return tx->cookie;
974 }
975
976 static struct dma_async_tx_descriptor *
977 coh901318_prep_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
978                       size_t size, unsigned long flags)
979 {
980         struct coh901318_lli *lli;
981         struct coh901318_desc *cohd;
982         unsigned long flg;
983         struct coh901318_chan *cohc = to_coh901318_chan(chan);
984         int lli_len;
985         u32 ctrl_last = cohc_chan_param(cohc)->ctrl_lli_last;
986         int ret;
987
988         spin_lock_irqsave(&cohc->lock, flg);
989
990         dev_vdbg(COHC_2_DEV(cohc),
991                  "[%s] channel %d src 0x%x dest 0x%x size %d\n",
992                  __func__, cohc->id, src, dest, size);
993
994         if (flags & DMA_PREP_INTERRUPT)
995                 /* Trigger interrupt after last lli */
996                 ctrl_last |= COH901318_CX_CTRL_TC_IRQ_ENABLE;
997
998         lli_len = size >> MAX_DMA_PACKET_SIZE_SHIFT;
999         if ((lli_len << MAX_DMA_PACKET_SIZE_SHIFT) < size)
1000                 lli_len++;
1001
1002         lli = coh901318_lli_alloc(&cohc->base->pool, lli_len);
1003
1004         if (lli == NULL)
1005                 goto err;
1006
1007         ret = coh901318_lli_fill_memcpy(
1008                 &cohc->base->pool, lli, src, size, dest,
1009                 cohc_chan_param(cohc)->ctrl_lli_chained,
1010                 ctrl_last);
1011         if (ret)
1012                 goto err;
1013
1014         COH_DBG(coh901318_list_print(cohc, lli));
1015
1016         /* Pick a descriptor to handle this transfer */
1017         cohd = coh901318_desc_get(cohc);
1018         cohd->lli = lli;
1019         cohd->flags = flags;
1020         cohd->desc.tx_submit = coh901318_tx_submit;
1021
1022         spin_unlock_irqrestore(&cohc->lock, flg);
1023
1024         return &cohd->desc;
1025  err:
1026         spin_unlock_irqrestore(&cohc->lock, flg);
1027         return NULL;
1028 }
1029
1030 static struct dma_async_tx_descriptor *
1031 coh901318_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
1032                         unsigned int sg_len, enum dma_data_direction direction,
1033                         unsigned long flags)
1034 {
1035         struct coh901318_chan *cohc = to_coh901318_chan(chan);
1036         struct coh901318_lli *lli;
1037         struct coh901318_desc *cohd;
1038         const struct coh901318_params *params;
1039         struct scatterlist *sg;
1040         int len = 0;
1041         int size;
1042         int i;
1043         u32 ctrl_chained = cohc_chan_param(cohc)->ctrl_lli_chained;
1044         u32 ctrl = cohc_chan_param(cohc)->ctrl_lli;
1045         u32 ctrl_last = cohc_chan_param(cohc)->ctrl_lli_last;
1046         u32 config;
1047         unsigned long flg;
1048         int ret;
1049
1050         if (!sgl)
1051                 goto out;
1052         if (sgl->length == 0)
1053                 goto out;
1054
1055         spin_lock_irqsave(&cohc->lock, flg);
1056
1057         dev_vdbg(COHC_2_DEV(cohc), "[%s] sg_len %d dir %d\n",
1058                  __func__, sg_len, direction);
1059
1060         if (flags & DMA_PREP_INTERRUPT)
1061                 /* Trigger interrupt after last lli */
1062                 ctrl_last |= COH901318_CX_CTRL_TC_IRQ_ENABLE;
1063
1064         params = cohc_chan_param(cohc);
1065         config = params->config;
1066         /*
1067          * Add runtime-specific control on top, make
1068          * sure the bits you set per peripheral channel are
1069          * cleared in the default config from the platform.
1070          */
1071         ctrl_chained |= cohc->runtime_ctrl;
1072         ctrl_last |= cohc->runtime_ctrl;
1073         ctrl |= cohc->runtime_ctrl;
1074
1075         if (direction == DMA_TO_DEVICE) {
1076                 u32 tx_flags = COH901318_CX_CTRL_PRDD_SOURCE |
1077                         COH901318_CX_CTRL_SRC_ADDR_INC_ENABLE;
1078
1079                 config |= COH901318_CX_CFG_RM_MEMORY_TO_PRIMARY;
1080                 ctrl_chained |= tx_flags;
1081                 ctrl_last |= tx_flags;
1082                 ctrl |= tx_flags;
1083         } else if (direction == DMA_FROM_DEVICE) {
1084                 u32 rx_flags = COH901318_CX_CTRL_PRDD_DEST |
1085                         COH901318_CX_CTRL_DST_ADDR_INC_ENABLE;
1086
1087                 config |= COH901318_CX_CFG_RM_PRIMARY_TO_MEMORY;
1088                 ctrl_chained |= rx_flags;
1089                 ctrl_last |= rx_flags;
1090                 ctrl |= rx_flags;
1091         } else
1092                 goto err_direction;
1093
1094         coh901318_set_conf(cohc, config);
1095
1096         /* The dma only supports transmitting packages up to
1097          * MAX_DMA_PACKET_SIZE. Calculate to total number of
1098          * dma elemts required to send the entire sg list
1099          */
1100         for_each_sg(sgl, sg, sg_len, i) {
1101                 unsigned int factor;
1102                 size = sg_dma_len(sg);
1103
1104                 if (size <= MAX_DMA_PACKET_SIZE) {
1105                         len++;
1106                         continue;
1107                 }
1108
1109                 factor = size >> MAX_DMA_PACKET_SIZE_SHIFT;
1110                 if ((factor << MAX_DMA_PACKET_SIZE_SHIFT) < size)
1111                         factor++;
1112
1113                 len += factor;
1114         }
1115
1116         pr_debug("Allocate %d lli:s for this transfer\n", len);
1117         lli = coh901318_lli_alloc(&cohc->base->pool, len);
1118
1119         if (lli == NULL)
1120                 goto err_dma_alloc;
1121
1122         /* initiate allocated lli list */
1123         ret = coh901318_lli_fill_sg(&cohc->base->pool, lli, sgl, sg_len,
1124                                     cohc_dev_addr(cohc),
1125                                     ctrl_chained,
1126                                     ctrl,
1127                                     ctrl_last,
1128                                     direction, COH901318_CX_CTRL_TC_IRQ_ENABLE);
1129         if (ret)
1130                 goto err_lli_fill;
1131
1132         /*
1133          * Set the default ctrl for the channel to the one from the lli,
1134          * things may have changed due to odd buffer alignment etc.
1135          */
1136         coh901318_set_ctrl(cohc, lli->control);
1137
1138         COH_DBG(coh901318_list_print(cohc, lli));
1139
1140         /* Pick a descriptor to handle this transfer */
1141         cohd = coh901318_desc_get(cohc);
1142         cohd->dir = direction;
1143         cohd->flags = flags;
1144         cohd->desc.tx_submit = coh901318_tx_submit;
1145         cohd->lli = lli;
1146
1147         spin_unlock_irqrestore(&cohc->lock, flg);
1148
1149         return &cohd->desc;
1150  err_lli_fill:
1151  err_dma_alloc:
1152  err_direction:
1153         spin_unlock_irqrestore(&cohc->lock, flg);
1154  out:
1155         return NULL;
1156 }
1157
1158 static enum dma_status
1159 coh901318_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
1160                  struct dma_tx_state *txstate)
1161 {
1162         struct coh901318_chan *cohc = to_coh901318_chan(chan);
1163         dma_cookie_t last_used;
1164         dma_cookie_t last_complete;
1165         int ret;
1166
1167         last_complete = cohc->completed;
1168         last_used = chan->cookie;
1169
1170         ret = dma_async_is_complete(cookie, last_complete, last_used);
1171
1172         dma_set_tx_state(txstate, last_complete, last_used,
1173                          coh901318_get_bytes_left(chan));
1174         if (ret == DMA_IN_PROGRESS && cohc->stopped)
1175                 ret = DMA_PAUSED;
1176
1177         return ret;
1178 }
1179
1180 static void
1181 coh901318_issue_pending(struct dma_chan *chan)
1182 {
1183         struct coh901318_chan *cohc = to_coh901318_chan(chan);
1184         unsigned long flags;
1185
1186         spin_lock_irqsave(&cohc->lock, flags);
1187
1188         /*
1189          * Busy means that pending jobs are already being processed,
1190          * and then there is no point in starting the queue: the
1191          * terminal count interrupt on the channel will take the next
1192          * job on the queue and execute it anyway.
1193          */
1194         if (!cohc->busy)
1195                 coh901318_queue_start(cohc);
1196
1197         spin_unlock_irqrestore(&cohc->lock, flags);
1198 }
1199
1200 /*
1201  * Here we wrap in the runtime dma control interface
1202  */
1203 struct burst_table {
1204         int burst_8bit;
1205         int burst_16bit;
1206         int burst_32bit;
1207         u32 reg;
1208 };
1209
1210 static const struct burst_table burst_sizes[] = {
1211         {
1212                 .burst_8bit = 64,
1213                 .burst_16bit = 32,
1214                 .burst_32bit = 16,
1215                 .reg = COH901318_CX_CTRL_BURST_COUNT_64_BYTES,
1216         },
1217         {
1218                 .burst_8bit = 48,
1219                 .burst_16bit = 24,
1220                 .burst_32bit = 12,
1221                 .reg = COH901318_CX_CTRL_BURST_COUNT_48_BYTES,
1222         },
1223         {
1224                 .burst_8bit = 32,
1225                 .burst_16bit = 16,
1226                 .burst_32bit = 8,
1227                 .reg = COH901318_CX_CTRL_BURST_COUNT_32_BYTES,
1228         },
1229         {
1230                 .burst_8bit = 16,
1231                 .burst_16bit = 8,
1232                 .burst_32bit = 4,
1233                 .reg = COH901318_CX_CTRL_BURST_COUNT_16_BYTES,
1234         },
1235         {
1236                 .burst_8bit = 8,
1237                 .burst_16bit = 4,
1238                 .burst_32bit = 2,
1239                 .reg = COH901318_CX_CTRL_BURST_COUNT_8_BYTES,
1240         },
1241         {
1242                 .burst_8bit = 4,
1243                 .burst_16bit = 2,
1244                 .burst_32bit = 1,
1245                 .reg = COH901318_CX_CTRL_BURST_COUNT_4_BYTES,
1246         },
1247         {
1248                 .burst_8bit = 2,
1249                 .burst_16bit = 1,
1250                 .burst_32bit = 0,
1251                 .reg = COH901318_CX_CTRL_BURST_COUNT_2_BYTES,
1252         },
1253         {
1254                 .burst_8bit = 1,
1255                 .burst_16bit = 0,
1256                 .burst_32bit = 0,
1257                 .reg = COH901318_CX_CTRL_BURST_COUNT_1_BYTE,
1258         },
1259 };
1260
1261 static void coh901318_dma_set_runtimeconfig(struct dma_chan *chan,
1262                         struct dma_slave_config *config)
1263 {
1264         struct coh901318_chan *cohc = to_coh901318_chan(chan);
1265         dma_addr_t addr;
1266         enum dma_slave_buswidth addr_width;
1267         u32 maxburst;
1268         u32 runtime_ctrl = 0;
1269         int i = 0;
1270
1271         /* We only support mem to per or per to mem transfers */
1272         if (config->direction == DMA_FROM_DEVICE) {
1273                 addr = config->src_addr;
1274                 addr_width = config->src_addr_width;
1275                 maxburst = config->src_maxburst;
1276         } else if (config->direction == DMA_TO_DEVICE) {
1277                 addr = config->dst_addr;
1278                 addr_width = config->dst_addr_width;
1279                 maxburst = config->dst_maxburst;
1280         } else {
1281                 dev_err(COHC_2_DEV(cohc), "illegal channel mode\n");
1282                 return;
1283         }
1284
1285         dev_dbg(COHC_2_DEV(cohc), "configure channel for %d byte transfers\n",
1286                 addr_width);
1287         switch (addr_width)  {
1288         case DMA_SLAVE_BUSWIDTH_1_BYTE:
1289                 runtime_ctrl |=
1290                         COH901318_CX_CTRL_SRC_BUS_SIZE_8_BITS |
1291                         COH901318_CX_CTRL_DST_BUS_SIZE_8_BITS;
1292
1293                 while (i < ARRAY_SIZE(burst_sizes)) {
1294                         if (burst_sizes[i].burst_8bit <= maxburst)
1295                                 break;
1296                         i++;
1297                 }
1298
1299                 break;
1300         case DMA_SLAVE_BUSWIDTH_2_BYTES:
1301                 runtime_ctrl |=
1302                         COH901318_CX_CTRL_SRC_BUS_SIZE_16_BITS |
1303                         COH901318_CX_CTRL_DST_BUS_SIZE_16_BITS;
1304
1305                 while (i < ARRAY_SIZE(burst_sizes)) {
1306                         if (burst_sizes[i].burst_16bit <= maxburst)
1307                                 break;
1308                         i++;
1309                 }
1310
1311                 break;
1312         case DMA_SLAVE_BUSWIDTH_4_BYTES:
1313                 /* Direction doesn't matter here, it's 32/32 bits */
1314                 runtime_ctrl |=
1315                         COH901318_CX_CTRL_SRC_BUS_SIZE_32_BITS |
1316                         COH901318_CX_CTRL_DST_BUS_SIZE_32_BITS;
1317
1318                 while (i < ARRAY_SIZE(burst_sizes)) {
1319                         if (burst_sizes[i].burst_32bit <= maxburst)
1320                                 break;
1321                         i++;
1322                 }
1323
1324                 break;
1325         default:
1326                 dev_err(COHC_2_DEV(cohc),
1327                         "bad runtimeconfig: alien address width\n");
1328                 return;
1329         }
1330
1331         runtime_ctrl |= burst_sizes[i].reg;
1332         dev_dbg(COHC_2_DEV(cohc),
1333                 "selected burst size %d bytes for address width %d bytes, maxburst %d\n",
1334                 burst_sizes[i].burst_8bit, addr_width, maxburst);
1335
1336         cohc->runtime_addr = addr;
1337         cohc->runtime_ctrl = runtime_ctrl;
1338 }
1339
1340 static int
1341 coh901318_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
1342                   unsigned long arg)
1343 {
1344         unsigned long flags;
1345         struct coh901318_chan *cohc = to_coh901318_chan(chan);
1346         struct coh901318_desc *cohd;
1347         void __iomem *virtbase = cohc->base->virtbase;
1348
1349         if (cmd == DMA_SLAVE_CONFIG) {
1350                 struct dma_slave_config *config =
1351                         (struct dma_slave_config *) arg;
1352
1353                 coh901318_dma_set_runtimeconfig(chan, config);
1354                 return 0;
1355           }
1356
1357         if (cmd == DMA_PAUSE) {
1358                 coh901318_pause(chan);
1359                 return 0;
1360         }
1361
1362         if (cmd == DMA_RESUME) {
1363                 coh901318_resume(chan);
1364                 return 0;
1365         }
1366
1367         if (cmd != DMA_TERMINATE_ALL)
1368                 return -ENXIO;
1369
1370         /* The remainder of this function terminates the transfer */
1371         coh901318_pause(chan);
1372         spin_lock_irqsave(&cohc->lock, flags);
1373
1374         /* Clear any pending BE or TC interrupt */
1375         if (cohc->id < 32) {
1376                 writel(1 << cohc->id, virtbase + COH901318_BE_INT_CLEAR1);
1377                 writel(1 << cohc->id, virtbase + COH901318_TC_INT_CLEAR1);
1378         } else {
1379                 writel(1 << (cohc->id - 32), virtbase +
1380                        COH901318_BE_INT_CLEAR2);
1381                 writel(1 << (cohc->id - 32), virtbase +
1382                        COH901318_TC_INT_CLEAR2);
1383         }
1384
1385         enable_powersave(cohc);
1386
1387         while ((cohd = coh901318_first_active_get(cohc))) {
1388                 /* release the lli allocation*/
1389                 coh901318_lli_free(&cohc->base->pool, &cohd->lli);
1390
1391                 /* return desc to free-list */
1392                 coh901318_desc_remove(cohd);
1393                 coh901318_desc_free(cohc, cohd);
1394         }
1395
1396         while ((cohd = coh901318_first_queued(cohc))) {
1397                 /* release the lli allocation*/
1398                 coh901318_lli_free(&cohc->base->pool, &cohd->lli);
1399
1400                 /* return desc to free-list */
1401                 coh901318_desc_remove(cohd);
1402                 coh901318_desc_free(cohc, cohd);
1403         }
1404
1405
1406         cohc->nbr_active_done = 0;
1407         cohc->busy = 0;
1408
1409         spin_unlock_irqrestore(&cohc->lock, flags);
1410
1411         return 0;
1412 }
1413
1414 void coh901318_base_init(struct dma_device *dma, const int *pick_chans,
1415                          struct coh901318_base *base)
1416 {
1417         int chans_i;
1418         int i = 0;
1419         struct coh901318_chan *cohc;
1420
1421         INIT_LIST_HEAD(&dma->channels);
1422
1423         for (chans_i = 0; pick_chans[chans_i] != -1; chans_i += 2) {
1424                 for (i = pick_chans[chans_i]; i <= pick_chans[chans_i+1]; i++) {
1425                         cohc = &base->chans[i];
1426
1427                         cohc->base = base;
1428                         cohc->chan.device = dma;
1429                         cohc->id = i;
1430
1431                         /* TODO: do we really need this lock if only one
1432                          * client is connected to each channel?
1433                          */
1434
1435                         spin_lock_init(&cohc->lock);
1436
1437                         cohc->nbr_active_done = 0;
1438                         cohc->busy = 0;
1439                         INIT_LIST_HEAD(&cohc->free);
1440                         INIT_LIST_HEAD(&cohc->active);
1441                         INIT_LIST_HEAD(&cohc->queue);
1442
1443                         tasklet_init(&cohc->tasklet, dma_tasklet,
1444                                      (unsigned long) cohc);
1445
1446                         list_add_tail(&cohc->chan.device_node,
1447                                       &dma->channels);
1448                 }
1449         }
1450 }
1451
1452 static int __init coh901318_probe(struct platform_device *pdev)
1453 {
1454         int err = 0;
1455         struct coh901318_platform *pdata;
1456         struct coh901318_base *base;
1457         int irq;
1458         struct resource *io;
1459
1460         io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1461         if (!io)
1462                 goto err_get_resource;
1463
1464         /* Map DMA controller registers to virtual memory */
1465         if (request_mem_region(io->start,
1466                                resource_size(io),
1467                                pdev->dev.driver->name) == NULL) {
1468                 err = -EBUSY;
1469                 goto err_request_mem;
1470         }
1471
1472         pdata = pdev->dev.platform_data;
1473         if (!pdata)
1474                 goto err_no_platformdata;
1475
1476         base = kmalloc(ALIGN(sizeof(struct coh901318_base), 4) +
1477                        pdata->max_channels *
1478                        sizeof(struct coh901318_chan),
1479                        GFP_KERNEL);
1480         if (!base)
1481                 goto err_alloc_coh_dma_channels;
1482
1483         base->chans = ((void *)base) + ALIGN(sizeof(struct coh901318_base), 4);
1484
1485         base->virtbase = ioremap(io->start, resource_size(io));
1486         if (!base->virtbase) {
1487                 err = -ENOMEM;
1488                 goto err_no_ioremap;
1489         }
1490
1491         base->dev = &pdev->dev;
1492         base->platform = pdata;
1493         spin_lock_init(&base->pm.lock);
1494         base->pm.started_channels = 0;
1495
1496         COH901318_DEBUGFS_ASSIGN(debugfs_dma_base, base);
1497
1498         platform_set_drvdata(pdev, base);
1499
1500         irq = platform_get_irq(pdev, 0);
1501         if (irq < 0)
1502                 goto err_no_irq;
1503
1504         err = request_irq(irq, dma_irq_handler, IRQF_DISABLED,
1505                           "coh901318", base);
1506         if (err) {
1507                 dev_crit(&pdev->dev,
1508                          "Cannot allocate IRQ for DMA controller!\n");
1509                 goto err_request_irq;
1510         }
1511
1512         err = coh901318_pool_create(&base->pool, &pdev->dev,
1513                                     sizeof(struct coh901318_lli),
1514                                     32);
1515         if (err)
1516                 goto err_pool_create;
1517
1518         /* init channels for device transfers */
1519         coh901318_base_init(&base->dma_slave,  base->platform->chans_slave,
1520                             base);
1521
1522         dma_cap_zero(base->dma_slave.cap_mask);
1523         dma_cap_set(DMA_SLAVE, base->dma_slave.cap_mask);
1524
1525         base->dma_slave.device_alloc_chan_resources = coh901318_alloc_chan_resources;
1526         base->dma_slave.device_free_chan_resources = coh901318_free_chan_resources;
1527         base->dma_slave.device_prep_slave_sg = coh901318_prep_slave_sg;
1528         base->dma_slave.device_tx_status = coh901318_tx_status;
1529         base->dma_slave.device_issue_pending = coh901318_issue_pending;
1530         base->dma_slave.device_control = coh901318_control;
1531         base->dma_slave.dev = &pdev->dev;
1532
1533         err = dma_async_device_register(&base->dma_slave);
1534
1535         if (err)
1536                 goto err_register_slave;
1537
1538         /* init channels for memcpy */
1539         coh901318_base_init(&base->dma_memcpy, base->platform->chans_memcpy,
1540                             base);
1541
1542         dma_cap_zero(base->dma_memcpy.cap_mask);
1543         dma_cap_set(DMA_MEMCPY, base->dma_memcpy.cap_mask);
1544
1545         base->dma_memcpy.device_alloc_chan_resources = coh901318_alloc_chan_resources;
1546         base->dma_memcpy.device_free_chan_resources = coh901318_free_chan_resources;
1547         base->dma_memcpy.device_prep_dma_memcpy = coh901318_prep_memcpy;
1548         base->dma_memcpy.device_tx_status = coh901318_tx_status;
1549         base->dma_memcpy.device_issue_pending = coh901318_issue_pending;
1550         base->dma_memcpy.device_control = coh901318_control;
1551         base->dma_memcpy.dev = &pdev->dev;
1552         /*
1553          * This controller can only access address at even 32bit boundaries,
1554          * i.e. 2^2
1555          */
1556         base->dma_memcpy.copy_align = 2;
1557         err = dma_async_device_register(&base->dma_memcpy);
1558
1559         if (err)
1560                 goto err_register_memcpy;
1561
1562         dev_info(&pdev->dev, "Initialized COH901318 DMA on virtual base 0x%08x\n",
1563                 (u32) base->virtbase);
1564
1565         return err;
1566
1567  err_register_memcpy:
1568         dma_async_device_unregister(&base->dma_slave);
1569  err_register_slave:
1570         coh901318_pool_destroy(&base->pool);
1571  err_pool_create:
1572         free_irq(platform_get_irq(pdev, 0), base);
1573  err_request_irq:
1574  err_no_irq:
1575         iounmap(base->virtbase);
1576  err_no_ioremap:
1577         kfree(base);
1578  err_alloc_coh_dma_channels:
1579  err_no_platformdata:
1580         release_mem_region(pdev->resource->start,
1581                            resource_size(pdev->resource));
1582  err_request_mem:
1583  err_get_resource:
1584         return err;
1585 }
1586
1587 static int __exit coh901318_remove(struct platform_device *pdev)
1588 {
1589         struct coh901318_base *base = platform_get_drvdata(pdev);
1590
1591         dma_async_device_unregister(&base->dma_memcpy);
1592         dma_async_device_unregister(&base->dma_slave);
1593         coh901318_pool_destroy(&base->pool);
1594         free_irq(platform_get_irq(pdev, 0), base);
1595         iounmap(base->virtbase);
1596         kfree(base);
1597         release_mem_region(pdev->resource->start,
1598                            resource_size(pdev->resource));
1599         return 0;
1600 }
1601
1602
1603 static struct platform_driver coh901318_driver = {
1604         .remove = __exit_p(coh901318_remove),
1605         .driver = {
1606                 .name   = "coh901318",
1607         },
1608 };
1609
1610 int __init coh901318_init(void)
1611 {
1612         return platform_driver_probe(&coh901318_driver, coh901318_probe);
1613 }
1614 subsys_initcall(coh901318_init);
1615
1616 void __exit coh901318_exit(void)
1617 {
1618         platform_driver_unregister(&coh901318_driver);
1619 }
1620 module_exit(coh901318_exit);
1621
1622 MODULE_LICENSE("GPL");
1623 MODULE_AUTHOR("Per Friden");