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