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