diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/crypto/ccp/ccp-dmaengine.c | 791 |
1 files changed, 791 insertions, 0 deletions
diff --git a/drivers/crypto/ccp/ccp-dmaengine.c b/drivers/crypto/ccp/ccp-dmaengine.c new file mode 100644 index 000000000..b386a7063 --- /dev/null +++ b/drivers/crypto/ccp/ccp-dmaengine.c @@ -0,0 +1,791 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * AMD Cryptographic Coprocessor (CCP) driver + * + * Copyright (C) 2016,2019 Advanced Micro Devices, Inc. + * + * Author: Gary R Hook <gary.hook@amd.com> + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/spinlock.h> +#include <linux/mutex.h> +#include <linux/ccp.h> + +#include "ccp-dev.h" +#include "../../dma/dmaengine.h" + +#define CCP_DMA_WIDTH(_mask) \ +({ \ + u64 mask = _mask + 1; \ + (mask == 0) ? 64 : fls64(mask); \ +}) + +/* The CCP as a DMA provider can be configured for public or private + * channels. Default is specified in the vdata for the device (PCI ID). + * This module parameter will override for all channels on all devices: + * dma_chan_attr = 0x2 to force all channels public + * = 0x1 to force all channels private + * = 0x0 to defer to the vdata setting + * = any other value: warning, revert to 0x0 + */ +static unsigned int dma_chan_attr = CCP_DMA_DFLT; +module_param(dma_chan_attr, uint, 0444); +MODULE_PARM_DESC(dma_chan_attr, "Set DMA channel visibility: 0 (default) = device defaults, 1 = make private, 2 = make public"); + +static unsigned int dmaengine = 1; +module_param(dmaengine, uint, 0444); +MODULE_PARM_DESC(dmaengine, "Register services with the DMA subsystem (any non-zero value, default: 1)"); + +static unsigned int ccp_get_dma_chan_attr(struct ccp_device *ccp) +{ + switch (dma_chan_attr) { + case CCP_DMA_DFLT: + return ccp->vdata->dma_chan_attr; + + case CCP_DMA_PRIV: + return DMA_PRIVATE; + + case CCP_DMA_PUB: + return 0; + + default: + dev_info_once(ccp->dev, "Invalid value for dma_chan_attr: %d\n", + dma_chan_attr); + return ccp->vdata->dma_chan_attr; + } +} + +static void ccp_free_cmd_resources(struct ccp_device *ccp, + struct list_head *list) +{ + struct ccp_dma_cmd *cmd, *ctmp; + + list_for_each_entry_safe(cmd, ctmp, list, entry) { + list_del(&cmd->entry); + kmem_cache_free(ccp->dma_cmd_cache, cmd); + } +} + +static void ccp_free_desc_resources(struct ccp_device *ccp, + struct list_head *list) +{ + struct ccp_dma_desc *desc, *dtmp; + + list_for_each_entry_safe(desc, dtmp, list, entry) { + ccp_free_cmd_resources(ccp, &desc->active); + ccp_free_cmd_resources(ccp, &desc->pending); + + list_del(&desc->entry); + kmem_cache_free(ccp->dma_desc_cache, desc); + } +} + +static void ccp_free_chan_resources(struct dma_chan *dma_chan) +{ + struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan, + dma_chan); + unsigned long flags; + + dev_dbg(chan->ccp->dev, "%s - chan=%p\n", __func__, chan); + + spin_lock_irqsave(&chan->lock, flags); + + ccp_free_desc_resources(chan->ccp, &chan->complete); + ccp_free_desc_resources(chan->ccp, &chan->active); + ccp_free_desc_resources(chan->ccp, &chan->pending); + ccp_free_desc_resources(chan->ccp, &chan->created); + + spin_unlock_irqrestore(&chan->lock, flags); +} + +static void ccp_cleanup_desc_resources(struct ccp_device *ccp, + struct list_head *list) +{ + struct ccp_dma_desc *desc, *dtmp; + + list_for_each_entry_safe_reverse(desc, dtmp, list, entry) { + if (!async_tx_test_ack(&desc->tx_desc)) + continue; + + dev_dbg(ccp->dev, "%s - desc=%p\n", __func__, desc); + + ccp_free_cmd_resources(ccp, &desc->active); + ccp_free_cmd_resources(ccp, &desc->pending); + + list_del(&desc->entry); + kmem_cache_free(ccp->dma_desc_cache, desc); + } +} + +static void ccp_do_cleanup(unsigned long data) +{ + struct ccp_dma_chan *chan = (struct ccp_dma_chan *)data; + unsigned long flags; + + dev_dbg(chan->ccp->dev, "%s - chan=%s\n", __func__, + dma_chan_name(&chan->dma_chan)); + + spin_lock_irqsave(&chan->lock, flags); + + ccp_cleanup_desc_resources(chan->ccp, &chan->complete); + + spin_unlock_irqrestore(&chan->lock, flags); +} + +static int ccp_issue_next_cmd(struct ccp_dma_desc *desc) +{ + struct ccp_dma_cmd *cmd; + int ret; + + cmd = list_first_entry(&desc->pending, struct ccp_dma_cmd, entry); + list_move(&cmd->entry, &desc->active); + + dev_dbg(desc->ccp->dev, "%s - tx %d, cmd=%p\n", __func__, + desc->tx_desc.cookie, cmd); + + ret = ccp_enqueue_cmd(&cmd->ccp_cmd); + if (!ret || (ret == -EINPROGRESS) || (ret == -EBUSY)) + return 0; + + dev_dbg(desc->ccp->dev, "%s - error: ret=%d, tx %d, cmd=%p\n", __func__, + ret, desc->tx_desc.cookie, cmd); + + return ret; +} + +static void ccp_free_active_cmd(struct ccp_dma_desc *desc) +{ + struct ccp_dma_cmd *cmd; + + cmd = list_first_entry_or_null(&desc->active, struct ccp_dma_cmd, + entry); + if (!cmd) + return; + + dev_dbg(desc->ccp->dev, "%s - freeing tx %d cmd=%p\n", + __func__, desc->tx_desc.cookie, cmd); + + list_del(&cmd->entry); + kmem_cache_free(desc->ccp->dma_cmd_cache, cmd); +} + +static struct ccp_dma_desc *__ccp_next_dma_desc(struct ccp_dma_chan *chan, + struct ccp_dma_desc *desc) +{ + /* Move current DMA descriptor to the complete list */ + if (desc) + list_move(&desc->entry, &chan->complete); + + /* Get the next DMA descriptor on the active list */ + desc = list_first_entry_or_null(&chan->active, struct ccp_dma_desc, + entry); + + return desc; +} + +static struct ccp_dma_desc *ccp_handle_active_desc(struct ccp_dma_chan *chan, + struct ccp_dma_desc *desc) +{ + struct dma_async_tx_descriptor *tx_desc; + unsigned long flags; + + /* Loop over descriptors until one is found with commands */ + do { + if (desc) { + /* Remove the DMA command from the list and free it */ + ccp_free_active_cmd(desc); + + if (!list_empty(&desc->pending)) { + /* No errors, keep going */ + if (desc->status != DMA_ERROR) + return desc; + + /* Error, free remaining commands and move on */ + ccp_free_cmd_resources(desc->ccp, + &desc->pending); + } + + tx_desc = &desc->tx_desc; + } else { + tx_desc = NULL; + } + + spin_lock_irqsave(&chan->lock, flags); + + if (desc) { + if (desc->status != DMA_ERROR) + desc->status = DMA_COMPLETE; + + dev_dbg(desc->ccp->dev, + "%s - tx %d complete, status=%u\n", __func__, + desc->tx_desc.cookie, desc->status); + + dma_cookie_complete(tx_desc); + dma_descriptor_unmap(tx_desc); + } + + desc = __ccp_next_dma_desc(chan, desc); + + spin_unlock_irqrestore(&chan->lock, flags); + + if (tx_desc) { + dmaengine_desc_get_callback_invoke(tx_desc, NULL); + + dma_run_dependencies(tx_desc); + } + } while (desc); + + return NULL; +} + +static struct ccp_dma_desc *__ccp_pending_to_active(struct ccp_dma_chan *chan) +{ + struct ccp_dma_desc *desc; + + if (list_empty(&chan->pending)) + return NULL; + + desc = list_empty(&chan->active) + ? list_first_entry(&chan->pending, struct ccp_dma_desc, entry) + : NULL; + + list_splice_tail_init(&chan->pending, &chan->active); + + return desc; +} + +static void ccp_cmd_callback(void *data, int err) +{ + struct ccp_dma_desc *desc = data; + struct ccp_dma_chan *chan; + int ret; + + if (err == -EINPROGRESS) + return; + + chan = container_of(desc->tx_desc.chan, struct ccp_dma_chan, + dma_chan); + + dev_dbg(chan->ccp->dev, "%s - tx %d callback, err=%d\n", + __func__, desc->tx_desc.cookie, err); + + if (err) + desc->status = DMA_ERROR; + + while (true) { + /* Check for DMA descriptor completion */ + desc = ccp_handle_active_desc(chan, desc); + + /* Don't submit cmd if no descriptor or DMA is paused */ + if (!desc || (chan->status == DMA_PAUSED)) + break; + + ret = ccp_issue_next_cmd(desc); + if (!ret) + break; + + desc->status = DMA_ERROR; + } + + tasklet_schedule(&chan->cleanup_tasklet); +} + +static dma_cookie_t ccp_tx_submit(struct dma_async_tx_descriptor *tx_desc) +{ + struct ccp_dma_desc *desc = container_of(tx_desc, struct ccp_dma_desc, + tx_desc); + struct ccp_dma_chan *chan; + dma_cookie_t cookie; + unsigned long flags; + + chan = container_of(tx_desc->chan, struct ccp_dma_chan, dma_chan); + + spin_lock_irqsave(&chan->lock, flags); + + cookie = dma_cookie_assign(tx_desc); + list_move_tail(&desc->entry, &chan->pending); + + spin_unlock_irqrestore(&chan->lock, flags); + + dev_dbg(chan->ccp->dev, "%s - added tx descriptor %d to pending list\n", + __func__, cookie); + + return cookie; +} + +static struct ccp_dma_cmd *ccp_alloc_dma_cmd(struct ccp_dma_chan *chan) +{ + struct ccp_dma_cmd *cmd; + + cmd = kmem_cache_alloc(chan->ccp->dma_cmd_cache, GFP_NOWAIT); + if (cmd) + memset(cmd, 0, sizeof(*cmd)); + + return cmd; +} + +static struct ccp_dma_desc *ccp_alloc_dma_desc(struct ccp_dma_chan *chan, + unsigned long flags) +{ + struct ccp_dma_desc *desc; + + desc = kmem_cache_zalloc(chan->ccp->dma_desc_cache, GFP_NOWAIT); + if (!desc) + return NULL; + + dma_async_tx_descriptor_init(&desc->tx_desc, &chan->dma_chan); + desc->tx_desc.flags = flags; + desc->tx_desc.tx_submit = ccp_tx_submit; + desc->ccp = chan->ccp; + INIT_LIST_HEAD(&desc->entry); + INIT_LIST_HEAD(&desc->pending); + INIT_LIST_HEAD(&desc->active); + desc->status = DMA_IN_PROGRESS; + + return desc; +} + +static struct ccp_dma_desc *ccp_create_desc(struct dma_chan *dma_chan, + struct scatterlist *dst_sg, + unsigned int dst_nents, + struct scatterlist *src_sg, + unsigned int src_nents, + unsigned long flags) +{ + struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan, + dma_chan); + struct ccp_device *ccp = chan->ccp; + struct ccp_dma_desc *desc; + struct ccp_dma_cmd *cmd; + struct ccp_cmd *ccp_cmd; + struct ccp_passthru_nomap_engine *ccp_pt; + unsigned int src_offset, src_len; + unsigned int dst_offset, dst_len; + unsigned int len; + unsigned long sflags; + size_t total_len; + + if (!dst_sg || !src_sg) + return NULL; + + if (!dst_nents || !src_nents) + return NULL; + + desc = ccp_alloc_dma_desc(chan, flags); + if (!desc) + return NULL; + + total_len = 0; + + src_len = sg_dma_len(src_sg); + src_offset = 0; + + dst_len = sg_dma_len(dst_sg); + dst_offset = 0; + + while (true) { + if (!src_len) { + src_nents--; + if (!src_nents) + break; + + src_sg = sg_next(src_sg); + if (!src_sg) + break; + + src_len = sg_dma_len(src_sg); + src_offset = 0; + continue; + } + + if (!dst_len) { + dst_nents--; + if (!dst_nents) + break; + + dst_sg = sg_next(dst_sg); + if (!dst_sg) + break; + + dst_len = sg_dma_len(dst_sg); + dst_offset = 0; + continue; + } + + len = min(dst_len, src_len); + + cmd = ccp_alloc_dma_cmd(chan); + if (!cmd) + goto err; + + ccp_cmd = &cmd->ccp_cmd; + ccp_cmd->ccp = chan->ccp; + ccp_pt = &ccp_cmd->u.passthru_nomap; + ccp_cmd->flags = CCP_CMD_MAY_BACKLOG; + ccp_cmd->flags |= CCP_CMD_PASSTHRU_NO_DMA_MAP; + ccp_cmd->engine = CCP_ENGINE_PASSTHRU; + ccp_pt->bit_mod = CCP_PASSTHRU_BITWISE_NOOP; + ccp_pt->byte_swap = CCP_PASSTHRU_BYTESWAP_NOOP; + ccp_pt->src_dma = sg_dma_address(src_sg) + src_offset; + ccp_pt->dst_dma = sg_dma_address(dst_sg) + dst_offset; + ccp_pt->src_len = len; + ccp_pt->final = 1; + ccp_cmd->callback = ccp_cmd_callback; + ccp_cmd->data = desc; + + list_add_tail(&cmd->entry, &desc->pending); + + dev_dbg(ccp->dev, + "%s - cmd=%p, src=%pad, dst=%pad, len=%llu\n", __func__, + cmd, &ccp_pt->src_dma, + &ccp_pt->dst_dma, ccp_pt->src_len); + + total_len += len; + + src_len -= len; + src_offset += len; + + dst_len -= len; + dst_offset += len; + } + + desc->len = total_len; + + if (list_empty(&desc->pending)) + goto err; + + dev_dbg(ccp->dev, "%s - desc=%p\n", __func__, desc); + + spin_lock_irqsave(&chan->lock, sflags); + + list_add_tail(&desc->entry, &chan->created); + + spin_unlock_irqrestore(&chan->lock, sflags); + + return desc; + +err: + ccp_free_cmd_resources(ccp, &desc->pending); + kmem_cache_free(ccp->dma_desc_cache, desc); + + return NULL; +} + +static struct dma_async_tx_descriptor *ccp_prep_dma_memcpy( + struct dma_chan *dma_chan, dma_addr_t dst, dma_addr_t src, size_t len, + unsigned long flags) +{ + struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan, + dma_chan); + struct ccp_dma_desc *desc; + struct scatterlist dst_sg, src_sg; + + dev_dbg(chan->ccp->dev, + "%s - src=%pad, dst=%pad, len=%zu, flags=%#lx\n", + __func__, &src, &dst, len, flags); + + sg_init_table(&dst_sg, 1); + sg_dma_address(&dst_sg) = dst; + sg_dma_len(&dst_sg) = len; + + sg_init_table(&src_sg, 1); + sg_dma_address(&src_sg) = src; + sg_dma_len(&src_sg) = len; + + desc = ccp_create_desc(dma_chan, &dst_sg, 1, &src_sg, 1, flags); + if (!desc) + return NULL; + + return &desc->tx_desc; +} + +static struct dma_async_tx_descriptor *ccp_prep_dma_interrupt( + struct dma_chan *dma_chan, unsigned long flags) +{ + struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan, + dma_chan); + struct ccp_dma_desc *desc; + + desc = ccp_alloc_dma_desc(chan, flags); + if (!desc) + return NULL; + + return &desc->tx_desc; +} + +static void ccp_issue_pending(struct dma_chan *dma_chan) +{ + struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan, + dma_chan); + struct ccp_dma_desc *desc; + unsigned long flags; + + dev_dbg(chan->ccp->dev, "%s\n", __func__); + + spin_lock_irqsave(&chan->lock, flags); + + desc = __ccp_pending_to_active(chan); + + spin_unlock_irqrestore(&chan->lock, flags); + + /* If there was nothing active, start processing */ + if (desc) + ccp_cmd_callback(desc, 0); +} + +static enum dma_status ccp_tx_status(struct dma_chan *dma_chan, + dma_cookie_t cookie, + struct dma_tx_state *state) +{ + struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan, + dma_chan); + struct ccp_dma_desc *desc; + enum dma_status ret; + unsigned long flags; + + if (chan->status == DMA_PAUSED) { + ret = DMA_PAUSED; + goto out; + } + + ret = dma_cookie_status(dma_chan, cookie, state); + if (ret == DMA_COMPLETE) { + spin_lock_irqsave(&chan->lock, flags); + + /* Get status from complete chain, if still there */ + list_for_each_entry(desc, &chan->complete, entry) { + if (desc->tx_desc.cookie != cookie) + continue; + + ret = desc->status; + break; + } + + spin_unlock_irqrestore(&chan->lock, flags); + } + +out: + dev_dbg(chan->ccp->dev, "%s - %u\n", __func__, ret); + + return ret; +} + +static int ccp_pause(struct dma_chan *dma_chan) +{ + struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan, + dma_chan); + + chan->status = DMA_PAUSED; + + /*TODO: Wait for active DMA to complete before returning? */ + + return 0; +} + +static int ccp_resume(struct dma_chan *dma_chan) +{ + struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan, + dma_chan); + struct ccp_dma_desc *desc; + unsigned long flags; + + spin_lock_irqsave(&chan->lock, flags); + + desc = list_first_entry_or_null(&chan->active, struct ccp_dma_desc, + entry); + + spin_unlock_irqrestore(&chan->lock, flags); + + /* Indicate the channel is running again */ + chan->status = DMA_IN_PROGRESS; + + /* If there was something active, re-start */ + if (desc) + ccp_cmd_callback(desc, 0); + + return 0; +} + +static int ccp_terminate_all(struct dma_chan *dma_chan) +{ + struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan, + dma_chan); + unsigned long flags; + + dev_dbg(chan->ccp->dev, "%s\n", __func__); + + /*TODO: Wait for active DMA to complete before continuing */ + + spin_lock_irqsave(&chan->lock, flags); + + /*TODO: Purge the complete list? */ + ccp_free_desc_resources(chan->ccp, &chan->active); + ccp_free_desc_resources(chan->ccp, &chan->pending); + ccp_free_desc_resources(chan->ccp, &chan->created); + + spin_unlock_irqrestore(&chan->lock, flags); + + return 0; +} + +static void ccp_dma_release(struct ccp_device *ccp) +{ + struct ccp_dma_chan *chan; + struct dma_chan *dma_chan; + unsigned int i; + + for (i = 0; i < ccp->cmd_q_count; i++) { + chan = ccp->ccp_dma_chan + i; + dma_chan = &chan->dma_chan; + + tasklet_kill(&chan->cleanup_tasklet); + list_del_rcu(&dma_chan->device_node); + } +} + +static void ccp_dma_release_channels(struct ccp_device *ccp) +{ + struct ccp_dma_chan *chan; + struct dma_chan *dma_chan; + unsigned int i; + + for (i = 0; i < ccp->cmd_q_count; i++) { + chan = ccp->ccp_dma_chan + i; + dma_chan = &chan->dma_chan; + + if (dma_chan->client_count) + dma_release_channel(dma_chan); + } +} + +int ccp_dmaengine_register(struct ccp_device *ccp) +{ + struct ccp_dma_chan *chan; + struct dma_device *dma_dev = &ccp->dma_dev; + struct dma_chan *dma_chan; + char *dma_cmd_cache_name; + char *dma_desc_cache_name; + unsigned int i; + int ret; + + if (!dmaengine) + return 0; + + ccp->ccp_dma_chan = devm_kcalloc(ccp->dev, ccp->cmd_q_count, + sizeof(*(ccp->ccp_dma_chan)), + GFP_KERNEL); + if (!ccp->ccp_dma_chan) + return -ENOMEM; + + dma_cmd_cache_name = devm_kasprintf(ccp->dev, GFP_KERNEL, + "%s-dmaengine-cmd-cache", + ccp->name); + if (!dma_cmd_cache_name) + return -ENOMEM; + + ccp->dma_cmd_cache = kmem_cache_create(dma_cmd_cache_name, + sizeof(struct ccp_dma_cmd), + sizeof(void *), + SLAB_HWCACHE_ALIGN, NULL); + if (!ccp->dma_cmd_cache) + return -ENOMEM; + + dma_desc_cache_name = devm_kasprintf(ccp->dev, GFP_KERNEL, + "%s-dmaengine-desc-cache", + ccp->name); + if (!dma_desc_cache_name) { + ret = -ENOMEM; + goto err_cache; + } + + ccp->dma_desc_cache = kmem_cache_create(dma_desc_cache_name, + sizeof(struct ccp_dma_desc), + sizeof(void *), + SLAB_HWCACHE_ALIGN, NULL); + if (!ccp->dma_desc_cache) { + ret = -ENOMEM; + goto err_cache; + } + + dma_dev->dev = ccp->dev; + dma_dev->src_addr_widths = CCP_DMA_WIDTH(dma_get_mask(ccp->dev)); + dma_dev->dst_addr_widths = CCP_DMA_WIDTH(dma_get_mask(ccp->dev)); + dma_dev->directions = DMA_MEM_TO_MEM; + dma_dev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR; + dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask); + dma_cap_set(DMA_INTERRUPT, dma_dev->cap_mask); + + /* The DMA channels for this device can be set to public or private, + * and overridden by the module parameter dma_chan_attr. + * Default: according to the value in vdata (dma_chan_attr=0) + * dma_chan_attr=0x1: all channels private (override vdata) + * dma_chan_attr=0x2: all channels public (override vdata) + */ + if (ccp_get_dma_chan_attr(ccp) == DMA_PRIVATE) + dma_cap_set(DMA_PRIVATE, dma_dev->cap_mask); + + INIT_LIST_HEAD(&dma_dev->channels); + for (i = 0; i < ccp->cmd_q_count; i++) { + chan = ccp->ccp_dma_chan + i; + dma_chan = &chan->dma_chan; + + chan->ccp = ccp; + + spin_lock_init(&chan->lock); + INIT_LIST_HEAD(&chan->created); + INIT_LIST_HEAD(&chan->pending); + INIT_LIST_HEAD(&chan->active); + INIT_LIST_HEAD(&chan->complete); + + tasklet_init(&chan->cleanup_tasklet, ccp_do_cleanup, + (unsigned long)chan); + + dma_chan->device = dma_dev; + dma_cookie_init(dma_chan); + + list_add_tail(&dma_chan->device_node, &dma_dev->channels); + } + + dma_dev->device_free_chan_resources = ccp_free_chan_resources; + dma_dev->device_prep_dma_memcpy = ccp_prep_dma_memcpy; + dma_dev->device_prep_dma_interrupt = ccp_prep_dma_interrupt; + dma_dev->device_issue_pending = ccp_issue_pending; + dma_dev->device_tx_status = ccp_tx_status; + dma_dev->device_pause = ccp_pause; + dma_dev->device_resume = ccp_resume; + dma_dev->device_terminate_all = ccp_terminate_all; + + ret = dma_async_device_register(dma_dev); + if (ret) + goto err_reg; + + return 0; + +err_reg: + ccp_dma_release(ccp); + kmem_cache_destroy(ccp->dma_desc_cache); + +err_cache: + kmem_cache_destroy(ccp->dma_cmd_cache); + + return ret; +} + +void ccp_dmaengine_unregister(struct ccp_device *ccp) +{ + struct dma_device *dma_dev = &ccp->dma_dev; + + if (!dmaengine) + return; + + ccp_dma_release_channels(ccp); + dma_async_device_unregister(dma_dev); + ccp_dma_release(ccp); + + kmem_cache_destroy(ccp->dma_desc_cache); + kmem_cache_destroy(ccp->dma_cmd_cache); +} |