2 * Dmaengine driver base library for DMA controllers, found on SH-based SoCs
4 * extracted from shdma.c
6 * Copyright (C) 2011-2012 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
7 * Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
8 * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
9 * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
11 * This is free software; you can redistribute it and/or modify
12 * it under the terms of version 2 of the GNU General Public License as
13 * published by the Free Software Foundation.
16 #include <linux/delay.h>
17 #include <linux/shdma-base.h>
18 #include <linux/dmaengine.h>
19 #include <linux/init.h>
20 #include <linux/interrupt.h>
21 #include <linux/module.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/slab.h>
24 #include <linux/spinlock.h>
26 #include "../dmaengine.h"
28 /* DMA descriptor control */
29 enum shdma_desc_status {
33 DESC_COMPLETED, /* completed, have to call callback */
34 DESC_WAITING, /* callback called, waiting for ack / re-submit */
37 #define NR_DESCS_PER_CHANNEL 32
39 #define to_shdma_chan(c) container_of(c, struct shdma_chan, dma_chan)
40 #define to_shdma_dev(d) container_of(d, struct shdma_dev, dma_dev)
43 * For slave DMA we assume, that there is a finite number of DMA slaves in the
44 * system, and that each such slave can only use a finite number of channels.
45 * We use slave channel IDs to make sure, that no such slave channel ID is
46 * allocated more than once.
48 static unsigned int slave_num = 256;
49 module_param(slave_num, uint, 0444);
51 /* A bitmask with slave_num bits */
52 static unsigned long *shdma_slave_used;
54 /* Called under spin_lock_irq(&schan->chan_lock") */
55 static void shdma_chan_xfer_ld_queue(struct shdma_chan *schan)
57 struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device);
58 const struct shdma_ops *ops = sdev->ops;
59 struct shdma_desc *sdesc;
62 if (ops->channel_busy(schan))
65 /* Find the first not transferred descriptor */
66 list_for_each_entry(sdesc, &schan->ld_queue, node)
67 if (sdesc->mark == DESC_SUBMITTED) {
68 ops->start_xfer(schan, sdesc);
73 static dma_cookie_t shdma_tx_submit(struct dma_async_tx_descriptor *tx)
75 struct shdma_desc *chunk, *c, *desc =
76 container_of(tx, struct shdma_desc, async_tx),
78 struct shdma_chan *schan = to_shdma_chan(tx->chan);
79 dma_async_tx_callback callback = tx->callback;
83 spin_lock_irq(&schan->chan_lock);
85 power_up = list_empty(&schan->ld_queue);
87 cookie = dma_cookie_assign(tx);
89 /* Mark all chunks of this descriptor as submitted, move to the queue */
90 list_for_each_entry_safe(chunk, c, desc->node.prev, node) {
92 * All chunks are on the global ld_free, so, we have to find
93 * the end of the chain ourselves
95 if (chunk != desc && (chunk->mark == DESC_IDLE ||
96 chunk->async_tx.cookie > 0 ||
97 chunk->async_tx.cookie == -EBUSY ||
98 &chunk->node == &schan->ld_free))
100 chunk->mark = DESC_SUBMITTED;
101 /* Callback goes to the last chunk */
102 chunk->async_tx.callback = NULL;
103 chunk->cookie = cookie;
104 list_move_tail(&chunk->node, &schan->ld_queue);
107 dev_dbg(schan->dev, "submit #%d@%p on %d\n",
108 tx->cookie, &last->async_tx, schan->id);
111 last->async_tx.callback = callback;
112 last->async_tx.callback_param = tx->callback_param;
116 schan->pm_state = SHDMA_PM_BUSY;
118 ret = pm_runtime_get(schan->dev);
120 spin_unlock_irq(&schan->chan_lock);
122 dev_err(schan->dev, "%s(): GET = %d\n", __func__, ret);
124 pm_runtime_barrier(schan->dev);
126 spin_lock_irq(&schan->chan_lock);
128 /* Have we been reset, while waiting? */
129 if (schan->pm_state != SHDMA_PM_ESTABLISHED) {
130 struct shdma_dev *sdev =
131 to_shdma_dev(schan->dma_chan.device);
132 const struct shdma_ops *ops = sdev->ops;
133 dev_dbg(schan->dev, "Bring up channel %d\n",
136 * TODO: .xfer_setup() might fail on some platforms.
137 * Make it int then, on error remove chunks from the
140 ops->setup_xfer(schan, schan->slave_id);
142 if (schan->pm_state == SHDMA_PM_PENDING)
143 shdma_chan_xfer_ld_queue(schan);
144 schan->pm_state = SHDMA_PM_ESTABLISHED;
148 * Tell .device_issue_pending() not to run the queue, interrupts
151 schan->pm_state = SHDMA_PM_PENDING;
154 spin_unlock_irq(&schan->chan_lock);
159 /* Called with desc_lock held */
160 static struct shdma_desc *shdma_get_desc(struct shdma_chan *schan)
162 struct shdma_desc *sdesc;
164 list_for_each_entry(sdesc, &schan->ld_free, node)
165 if (sdesc->mark != DESC_PREPARED) {
166 BUG_ON(sdesc->mark != DESC_IDLE);
167 list_del(&sdesc->node);
174 static int shdma_setup_slave(struct shdma_chan *schan, int slave_id)
176 struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device);
177 const struct shdma_ops *ops = sdev->ops;
180 if (slave_id < 0 || slave_id >= slave_num)
183 if (test_and_set_bit(slave_id, shdma_slave_used))
186 ret = ops->set_slave(schan, slave_id, false);
188 clear_bit(slave_id, shdma_slave_used);
192 schan->slave_id = slave_id;
198 * This is the standard shdma filter function to be used as a replacement to the
199 * "old" method, using the .private pointer. If for some reason you allocate a
200 * channel without slave data, use something like ERR_PTR(-EINVAL) as a filter
201 * parameter. If this filter is used, the slave driver, after calling
202 * dma_request_channel(), will also have to call dmaengine_slave_config() with
203 * .slave_id, .direction, and either .src_addr or .dst_addr set.
204 * NOTE: this filter doesn't support multiple DMAC drivers with the DMA_SLAVE
205 * capability! If this becomes a requirement, hardware glue drivers, using this
206 * services would have to provide their own filters, which first would check
207 * the device driver, similar to how other DMAC drivers, e.g., sa11x0-dma.c, do
208 * this, and only then, in case of a match, call this common filter.
210 bool shdma_chan_filter(struct dma_chan *chan, void *arg)
212 struct shdma_chan *schan = to_shdma_chan(chan);
213 struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device);
214 const struct shdma_ops *ops = sdev->ops;
215 int slave_id = (int)arg;
219 /* No slave requested - arbitrary channel */
222 if (slave_id >= slave_num)
225 ret = ops->set_slave(schan, slave_id, true);
231 EXPORT_SYMBOL(shdma_chan_filter);
233 static int shdma_alloc_chan_resources(struct dma_chan *chan)
235 struct shdma_chan *schan = to_shdma_chan(chan);
236 struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device);
237 const struct shdma_ops *ops = sdev->ops;
238 struct shdma_desc *desc;
239 struct shdma_slave *slave = chan->private;
243 * This relies on the guarantee from dmaengine that alloc_chan_resources
244 * never runs concurrently with itself or free_chan_resources.
247 /* Legacy mode: .private is set in filter */
248 ret = shdma_setup_slave(schan, slave->slave_id);
252 schan->slave_id = -EINVAL;
255 schan->desc = kcalloc(NR_DESCS_PER_CHANNEL,
256 sdev->desc_size, GFP_KERNEL);
261 schan->desc_num = NR_DESCS_PER_CHANNEL;
263 for (i = 0; i < NR_DESCS_PER_CHANNEL; i++) {
264 desc = ops->embedded_desc(schan->desc, i);
265 dma_async_tx_descriptor_init(&desc->async_tx,
267 desc->async_tx.tx_submit = shdma_tx_submit;
268 desc->mark = DESC_IDLE;
270 list_add(&desc->node, &schan->ld_free);
273 return NR_DESCS_PER_CHANNEL;
278 clear_bit(slave->slave_id, shdma_slave_used);
279 chan->private = NULL;
283 static dma_async_tx_callback __ld_cleanup(struct shdma_chan *schan, bool all)
285 struct shdma_desc *desc, *_desc;
286 /* Is the "exposed" head of a chain acked? */
287 bool head_acked = false;
288 dma_cookie_t cookie = 0;
289 dma_async_tx_callback callback = NULL;
293 spin_lock_irqsave(&schan->chan_lock, flags);
294 list_for_each_entry_safe(desc, _desc, &schan->ld_queue, node) {
295 struct dma_async_tx_descriptor *tx = &desc->async_tx;
297 BUG_ON(tx->cookie > 0 && tx->cookie != desc->cookie);
298 BUG_ON(desc->mark != DESC_SUBMITTED &&
299 desc->mark != DESC_COMPLETED &&
300 desc->mark != DESC_WAITING);
303 * queue is ordered, and we use this loop to (1) clean up all
304 * completed descriptors, and to (2) update descriptor flags of
305 * any chunks in a (partially) completed chain
307 if (!all && desc->mark == DESC_SUBMITTED &&
308 desc->cookie != cookie)
314 if (desc->mark == DESC_COMPLETED && desc->chunks == 1) {
315 if (schan->dma_chan.completed_cookie != desc->cookie - 1)
317 "Completing cookie %d, expected %d\n",
319 schan->dma_chan.completed_cookie + 1);
320 schan->dma_chan.completed_cookie = desc->cookie;
323 /* Call callback on the last chunk */
324 if (desc->mark == DESC_COMPLETED && tx->callback) {
325 desc->mark = DESC_WAITING;
326 callback = tx->callback;
327 param = tx->callback_param;
328 dev_dbg(schan->dev, "descriptor #%d@%p on %d callback\n",
329 tx->cookie, tx, schan->id);
330 BUG_ON(desc->chunks != 1);
334 if (tx->cookie > 0 || tx->cookie == -EBUSY) {
335 if (desc->mark == DESC_COMPLETED) {
336 BUG_ON(tx->cookie < 0);
337 desc->mark = DESC_WAITING;
339 head_acked = async_tx_test_ack(tx);
341 switch (desc->mark) {
343 desc->mark = DESC_WAITING;
347 async_tx_ack(&desc->async_tx);
351 dev_dbg(schan->dev, "descriptor %p #%d completed.\n",
354 if (((desc->mark == DESC_COMPLETED ||
355 desc->mark == DESC_WAITING) &&
356 async_tx_test_ack(&desc->async_tx)) || all) {
357 /* Remove from ld_queue list */
358 desc->mark = DESC_IDLE;
360 list_move(&desc->node, &schan->ld_free);
362 if (list_empty(&schan->ld_queue)) {
363 dev_dbg(schan->dev, "Bring down channel %d\n", schan->id);
364 pm_runtime_put(schan->dev);
365 schan->pm_state = SHDMA_PM_ESTABLISHED;
370 if (all && !callback)
372 * Terminating and the loop completed normally: forgive
373 * uncompleted cookies
375 schan->dma_chan.completed_cookie = schan->dma_chan.cookie;
377 spin_unlock_irqrestore(&schan->chan_lock, flags);
386 * shdma_chan_ld_cleanup - Clean up link descriptors
388 * Clean up the ld_queue of DMA channel.
390 static void shdma_chan_ld_cleanup(struct shdma_chan *schan, bool all)
392 while (__ld_cleanup(schan, all))
397 * shdma_free_chan_resources - Free all resources of the channel.
399 static void shdma_free_chan_resources(struct dma_chan *chan)
401 struct shdma_chan *schan = to_shdma_chan(chan);
402 struct shdma_dev *sdev = to_shdma_dev(chan->device);
403 const struct shdma_ops *ops = sdev->ops;
406 /* Protect against ISR */
407 spin_lock_irq(&schan->chan_lock);
408 ops->halt_channel(schan);
409 spin_unlock_irq(&schan->chan_lock);
411 /* Now no new interrupts will occur */
413 /* Prepared and not submitted descriptors can still be on the queue */
414 if (!list_empty(&schan->ld_queue))
415 shdma_chan_ld_cleanup(schan, true);
417 if (schan->slave_id >= 0) {
418 /* The caller is holding dma_list_mutex */
419 clear_bit(schan->slave_id, shdma_slave_used);
420 chan->private = NULL;
423 spin_lock_irq(&schan->chan_lock);
425 list_splice_init(&schan->ld_free, &list);
428 spin_unlock_irq(&schan->chan_lock);
434 * shdma_add_desc - get, set up and return one transfer descriptor
435 * @schan: DMA channel
436 * @flags: DMA transfer flags
437 * @dst: destination DMA address, incremented when direction equals
438 * DMA_DEV_TO_MEM or DMA_MEM_TO_MEM
439 * @src: source DMA address, incremented when direction equals
440 * DMA_MEM_TO_DEV or DMA_MEM_TO_MEM
441 * @len: DMA transfer length
442 * @first: if NULL, set to the current descriptor and cookie set to -EBUSY
443 * @direction: needed for slave DMA to decide which address to keep constant,
444 * equals DMA_MEM_TO_MEM for MEMCPY
445 * Returns 0 or an error
446 * Locks: called with desc_lock held
448 static struct shdma_desc *shdma_add_desc(struct shdma_chan *schan,
449 unsigned long flags, dma_addr_t *dst, dma_addr_t *src, size_t *len,
450 struct shdma_desc **first, enum dma_transfer_direction direction)
452 struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device);
453 const struct shdma_ops *ops = sdev->ops;
454 struct shdma_desc *new;
455 size_t copy_size = *len;
460 /* Allocate the link descriptor from the free list */
461 new = shdma_get_desc(schan);
463 dev_err(schan->dev, "No free link descriptor available\n");
467 ops->desc_setup(schan, new, *src, *dst, ©_size);
471 new->async_tx.cookie = -EBUSY;
474 /* Other desc - invisible to the user */
475 new->async_tx.cookie = -EINVAL;
479 "chaining (%u/%u)@%x -> %x with %p, cookie %d\n",
480 copy_size, *len, *src, *dst, &new->async_tx,
481 new->async_tx.cookie);
483 new->mark = DESC_PREPARED;
484 new->async_tx.flags = flags;
485 new->direction = direction;
489 if (direction == DMA_MEM_TO_MEM || direction == DMA_MEM_TO_DEV)
491 if (direction == DMA_MEM_TO_MEM || direction == DMA_DEV_TO_MEM)
498 * shdma_prep_sg - prepare transfer descriptors from an SG list
500 * Common routine for public (MEMCPY) and slave DMA. The MEMCPY case is also
501 * converted to scatter-gather to guarantee consistent locking and a correct
502 * list manipulation. For slave DMA direction carries the usual meaning, and,
503 * logically, the SG list is RAM and the addr variable contains slave address,
504 * e.g., the FIFO I/O register. For MEMCPY direction equals DMA_MEM_TO_MEM
505 * and the SG list contains only one element and points at the source buffer.
507 static struct dma_async_tx_descriptor *shdma_prep_sg(struct shdma_chan *schan,
508 struct scatterlist *sgl, unsigned int sg_len, dma_addr_t *addr,
509 enum dma_transfer_direction direction, unsigned long flags)
511 struct scatterlist *sg;
512 struct shdma_desc *first = NULL, *new = NULL /* compiler... */;
515 unsigned long irq_flags;
518 for_each_sg(sgl, sg, sg_len, i)
519 chunks += DIV_ROUND_UP(sg_dma_len(sg), schan->max_xfer_len);
521 /* Have to lock the whole loop to protect against concurrent release */
522 spin_lock_irqsave(&schan->chan_lock, irq_flags);
526 * first descriptor is what user is dealing with in all API calls, its
527 * cookie is at first set to -EBUSY, at tx-submit to a positive
529 * if more than one chunk is needed further chunks have cookie = -EINVAL
530 * the last chunk, if not equal to the first, has cookie = -ENOSPC
531 * all chunks are linked onto the tx_list head with their .node heads
532 * only during this function, then they are immediately spliced
533 * back onto the free list in form of a chain
535 for_each_sg(sgl, sg, sg_len, i) {
536 dma_addr_t sg_addr = sg_dma_address(sg);
537 size_t len = sg_dma_len(sg);
543 dev_dbg(schan->dev, "Add SG #%d@%p[%d], dma %llx\n",
544 i, sg, len, (unsigned long long)sg_addr);
546 if (direction == DMA_DEV_TO_MEM)
547 new = shdma_add_desc(schan, flags,
548 &sg_addr, addr, &len, &first,
551 new = shdma_add_desc(schan, flags,
552 addr, &sg_addr, &len, &first,
557 new->chunks = chunks--;
558 list_add_tail(&new->node, &tx_list);
563 new->async_tx.cookie = -ENOSPC;
565 /* Put them back on the free list, so, they don't get lost */
566 list_splice_tail(&tx_list, &schan->ld_free);
568 spin_unlock_irqrestore(&schan->chan_lock, irq_flags);
570 return &first->async_tx;
573 list_for_each_entry(new, &tx_list, node)
574 new->mark = DESC_IDLE;
575 list_splice(&tx_list, &schan->ld_free);
577 spin_unlock_irqrestore(&schan->chan_lock, irq_flags);
582 static struct dma_async_tx_descriptor *shdma_prep_memcpy(
583 struct dma_chan *chan, dma_addr_t dma_dest, dma_addr_t dma_src,
584 size_t len, unsigned long flags)
586 struct shdma_chan *schan = to_shdma_chan(chan);
587 struct scatterlist sg;
592 BUG_ON(!schan->desc_num);
594 sg_init_table(&sg, 1);
595 sg_set_page(&sg, pfn_to_page(PFN_DOWN(dma_src)), len,
596 offset_in_page(dma_src));
597 sg_dma_address(&sg) = dma_src;
598 sg_dma_len(&sg) = len;
600 return shdma_prep_sg(schan, &sg, 1, &dma_dest, DMA_MEM_TO_MEM, flags);
603 static struct dma_async_tx_descriptor *shdma_prep_slave_sg(
604 struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len,
605 enum dma_transfer_direction direction, unsigned long flags, void *context)
607 struct shdma_chan *schan = to_shdma_chan(chan);
608 struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device);
609 const struct shdma_ops *ops = sdev->ops;
610 int slave_id = schan->slave_id;
611 dma_addr_t slave_addr;
616 BUG_ON(!schan->desc_num);
618 /* Someone calling slave DMA on a generic channel? */
619 if (slave_id < 0 || !sg_len) {
620 dev_warn(schan->dev, "%s: bad parameter: len=%d, id=%d\n",
621 __func__, sg_len, slave_id);
625 slave_addr = ops->slave_addr(schan);
627 return shdma_prep_sg(schan, sgl, sg_len, &slave_addr,
631 static int shdma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
634 struct shdma_chan *schan = to_shdma_chan(chan);
635 struct shdma_dev *sdev = to_shdma_dev(chan->device);
636 const struct shdma_ops *ops = sdev->ops;
637 struct dma_slave_config *config;
642 case DMA_TERMINATE_ALL:
643 spin_lock_irqsave(&schan->chan_lock, flags);
644 ops->halt_channel(schan);
646 if (ops->get_partial && !list_empty(&schan->ld_queue)) {
647 /* Record partial transfer */
648 struct shdma_desc *desc = list_first_entry(&schan->ld_queue,
649 struct shdma_desc, node);
650 desc->partial = ops->get_partial(schan, desc);
653 spin_unlock_irqrestore(&schan->chan_lock, flags);
655 shdma_chan_ld_cleanup(schan, true);
657 case DMA_SLAVE_CONFIG:
659 * So far only .slave_id is used, but the slave drivers are
660 * encouraged to also set a transfer direction and an address.
665 * We could lock this, but you shouldn't be configuring the
666 * channel, while using it...
668 config = (struct dma_slave_config *)arg;
669 ret = shdma_setup_slave(schan, config->slave_id);
680 static void shdma_issue_pending(struct dma_chan *chan)
682 struct shdma_chan *schan = to_shdma_chan(chan);
684 spin_lock_irq(&schan->chan_lock);
685 if (schan->pm_state == SHDMA_PM_ESTABLISHED)
686 shdma_chan_xfer_ld_queue(schan);
688 schan->pm_state = SHDMA_PM_PENDING;
689 spin_unlock_irq(&schan->chan_lock);
692 static enum dma_status shdma_tx_status(struct dma_chan *chan,
694 struct dma_tx_state *txstate)
696 struct shdma_chan *schan = to_shdma_chan(chan);
697 enum dma_status status;
700 shdma_chan_ld_cleanup(schan, false);
702 spin_lock_irqsave(&schan->chan_lock, flags);
704 status = dma_cookie_status(chan, cookie, txstate);
707 * If we don't find cookie on the queue, it has been aborted and we have
710 if (status != DMA_SUCCESS) {
711 struct shdma_desc *sdesc;
713 list_for_each_entry(sdesc, &schan->ld_queue, node)
714 if (sdesc->cookie == cookie) {
715 status = DMA_IN_PROGRESS;
720 spin_unlock_irqrestore(&schan->chan_lock, flags);
725 /* Called from error IRQ or NMI */
726 bool shdma_reset(struct shdma_dev *sdev)
728 const struct shdma_ops *ops = sdev->ops;
729 struct shdma_chan *schan;
730 unsigned int handled = 0;
733 /* Reset all channels */
734 shdma_for_each_chan(schan, sdev, i) {
735 struct shdma_desc *sdesc;
741 spin_lock(&schan->chan_lock);
743 /* Stop the channel */
744 ops->halt_channel(schan);
746 list_splice_init(&schan->ld_queue, &dl);
748 if (!list_empty(&dl)) {
749 dev_dbg(schan->dev, "Bring down channel %d\n", schan->id);
750 pm_runtime_put(schan->dev);
752 schan->pm_state = SHDMA_PM_ESTABLISHED;
754 spin_unlock(&schan->chan_lock);
757 list_for_each_entry(sdesc, &dl, node) {
758 struct dma_async_tx_descriptor *tx = &sdesc->async_tx;
759 sdesc->mark = DESC_IDLE;
761 tx->callback(tx->callback_param);
764 spin_lock(&schan->chan_lock);
765 list_splice(&dl, &schan->ld_free);
766 spin_unlock(&schan->chan_lock);
773 EXPORT_SYMBOL(shdma_reset);
775 static irqreturn_t chan_irq(int irq, void *dev)
777 struct shdma_chan *schan = dev;
778 const struct shdma_ops *ops =
779 to_shdma_dev(schan->dma_chan.device)->ops;
782 spin_lock(&schan->chan_lock);
784 ret = ops->chan_irq(schan, irq) ? IRQ_WAKE_THREAD : IRQ_NONE;
786 spin_unlock(&schan->chan_lock);
791 static irqreturn_t chan_irqt(int irq, void *dev)
793 struct shdma_chan *schan = dev;
794 const struct shdma_ops *ops =
795 to_shdma_dev(schan->dma_chan.device)->ops;
796 struct shdma_desc *sdesc;
798 spin_lock_irq(&schan->chan_lock);
799 list_for_each_entry(sdesc, &schan->ld_queue, node) {
800 if (sdesc->mark == DESC_SUBMITTED &&
801 ops->desc_completed(schan, sdesc)) {
802 dev_dbg(schan->dev, "done #%d@%p\n",
803 sdesc->async_tx.cookie, &sdesc->async_tx);
804 sdesc->mark = DESC_COMPLETED;
809 shdma_chan_xfer_ld_queue(schan);
810 spin_unlock_irq(&schan->chan_lock);
812 shdma_chan_ld_cleanup(schan, false);
817 int shdma_request_irq(struct shdma_chan *schan, int irq,
818 unsigned long flags, const char *name)
820 int ret = request_threaded_irq(irq, chan_irq, chan_irqt,
823 schan->irq = ret < 0 ? ret : irq;
827 EXPORT_SYMBOL(shdma_request_irq);
829 void shdma_free_irq(struct shdma_chan *schan)
832 free_irq(schan->irq, schan);
834 EXPORT_SYMBOL(shdma_free_irq);
836 void shdma_chan_probe(struct shdma_dev *sdev,
837 struct shdma_chan *schan, int id)
839 schan->pm_state = SHDMA_PM_ESTABLISHED;
841 /* reference struct dma_device */
842 schan->dma_chan.device = &sdev->dma_dev;
843 dma_cookie_init(&schan->dma_chan);
845 schan->dev = sdev->dma_dev.dev;
848 if (!schan->max_xfer_len)
849 schan->max_xfer_len = PAGE_SIZE;
851 spin_lock_init(&schan->chan_lock);
853 /* Init descripter manage list */
854 INIT_LIST_HEAD(&schan->ld_queue);
855 INIT_LIST_HEAD(&schan->ld_free);
857 /* Add the channel to DMA device channel list */
858 list_add_tail(&schan->dma_chan.device_node,
859 &sdev->dma_dev.channels);
860 sdev->schan[sdev->dma_dev.chancnt++] = schan;
862 EXPORT_SYMBOL(shdma_chan_probe);
864 void shdma_chan_remove(struct shdma_chan *schan)
866 list_del(&schan->dma_chan.device_node);
868 EXPORT_SYMBOL(shdma_chan_remove);
870 int shdma_init(struct device *dev, struct shdma_dev *sdev,
873 struct dma_device *dma_dev = &sdev->dma_dev;
876 * Require all call-backs for now, they can trivially be made optional
881 !sdev->ops->embedded_desc ||
882 !sdev->ops->start_xfer ||
883 !sdev->ops->setup_xfer ||
884 !sdev->ops->set_slave ||
885 !sdev->ops->desc_setup ||
886 !sdev->ops->slave_addr ||
887 !sdev->ops->channel_busy ||
888 !sdev->ops->halt_channel ||
889 !sdev->ops->desc_completed)
892 sdev->schan = kcalloc(chan_num, sizeof(*sdev->schan), GFP_KERNEL);
896 INIT_LIST_HEAD(&dma_dev->channels);
898 /* Common and MEMCPY operations */
899 dma_dev->device_alloc_chan_resources
900 = shdma_alloc_chan_resources;
901 dma_dev->device_free_chan_resources = shdma_free_chan_resources;
902 dma_dev->device_prep_dma_memcpy = shdma_prep_memcpy;
903 dma_dev->device_tx_status = shdma_tx_status;
904 dma_dev->device_issue_pending = shdma_issue_pending;
906 /* Compulsory for DMA_SLAVE fields */
907 dma_dev->device_prep_slave_sg = shdma_prep_slave_sg;
908 dma_dev->device_control = shdma_control;
914 EXPORT_SYMBOL(shdma_init);
916 void shdma_cleanup(struct shdma_dev *sdev)
920 EXPORT_SYMBOL(shdma_cleanup);
922 static int __init shdma_enter(void)
924 shdma_slave_used = kzalloc(DIV_ROUND_UP(slave_num, BITS_PER_LONG) *
925 sizeof(long), GFP_KERNEL);
926 if (!shdma_slave_used)
930 module_init(shdma_enter);
932 static void __exit shdma_exit(void)
934 kfree(shdma_slave_used);
936 module_exit(shdma_exit);
938 MODULE_LICENSE("GPL v2");
939 MODULE_DESCRIPTION("SH-DMA driver base library");
940 MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");