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1/*
2 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
3 * Takashi Iwai <tiwai@suse.de>
4 *
5 * Generic memory allocators
6 *
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 *
22 */
23
24#include <linux/slab.h>
25#include <linux/mm.h>
26#include <linux/dma-mapping.h>
27#include <linux/genalloc.h>
28#include <sound/memalloc.h>
29
30/*
31 *
32 * Generic memory allocators
33 *
34 */
35
36/**
37 * snd_malloc_pages - allocate pages with the given size
38 * @size: the size to allocate in bytes
39 * @gfp_flags: the allocation conditions, GFP_XXX
40 *
41 * Allocates the physically contiguous pages with the given size.
42 *
43 * Return: The pointer of the buffer, or %NULL if no enough memory.
44 */
45void *snd_malloc_pages(size_t size, gfp_t gfp_flags)
46{
47 int pg;
48
49 if (WARN_ON(!size))
50 return NULL;
51 if (WARN_ON(!gfp_flags))
52 return NULL;
53 gfp_flags |= __GFP_COMP; /* compound page lets parts be mapped */
54 pg = get_order(size);
55 return (void *) __get_free_pages(gfp_flags, pg);
56}
57
58/**
59 * snd_free_pages - release the pages
60 * @ptr: the buffer pointer to release
61 * @size: the allocated buffer size
62 *
63 * Releases the buffer allocated via snd_malloc_pages().
64 */
65void snd_free_pages(void *ptr, size_t size)
66{
67 int pg;
68
69 if (ptr == NULL)
70 return;
71 pg = get_order(size);
72 free_pages((unsigned long) ptr, pg);
73}
74
75/*
76 *
77 * Bus-specific memory allocators
78 *
79 */
80
81#ifdef CONFIG_HAS_DMA
82/* allocate the coherent DMA pages */
83static void *snd_malloc_dev_pages(struct device *dev, size_t size, dma_addr_t *dma)
84{
85 int pg;
86 gfp_t gfp_flags;
87
88 if (WARN_ON(!dma))
89 return NULL;
90 pg = get_order(size);
91 gfp_flags = GFP_KERNEL
92 | __GFP_COMP /* compound page lets parts be mapped */
93 | __GFP_NORETRY /* don't trigger OOM-killer */
94 | __GFP_NOWARN; /* no stack trace print - this call is non-critical */
95 return dma_alloc_coherent(dev, PAGE_SIZE << pg, dma, gfp_flags);
96}
97
98/* free the coherent DMA pages */
99static void snd_free_dev_pages(struct device *dev, size_t size, void *ptr,
100 dma_addr_t dma)
101{
102 int pg;
103
104 if (ptr == NULL)
105 return;
106 pg = get_order(size);
107 dma_free_coherent(dev, PAGE_SIZE << pg, ptr, dma);
108}
109
110#ifdef CONFIG_GENERIC_ALLOCATOR
111/**
112 * snd_malloc_dev_iram - allocate memory from on-chip internal ram
113 * @dmab: buffer allocation record to store the allocated data
114 * @size: number of bytes to allocate from the iram
115 *
116 * This function requires iram phandle provided via of_node
117 */
118static void snd_malloc_dev_iram(struct snd_dma_buffer *dmab, size_t size)
119{
120 struct device *dev = dmab->dev.dev;
121 struct gen_pool *pool = NULL;
122
123 dmab->area = NULL;
124 dmab->addr = 0;
125
126 if (dev->of_node)
127 pool = of_get_named_gen_pool(dev->of_node, "iram", 0);
128
129 if (!pool)
130 return;
131
132 /* Assign the pool into private_data field */
133 dmab->private_data = pool;
134
135 dmab->area = gen_pool_dma_alloc(pool, size, &dmab->addr);
136}
137
138/**
139 * snd_free_dev_iram - free allocated specific memory from on-chip internal ram
140 * @dmab: buffer allocation record to store the allocated data
141 */
142static void snd_free_dev_iram(struct snd_dma_buffer *dmab)
143{
144 struct gen_pool *pool = dmab->private_data;
145
146 if (pool && dmab->area)
147 gen_pool_free(pool, (unsigned long)dmab->area, dmab->bytes);
148}
149#endif /* CONFIG_GENERIC_ALLOCATOR */
150#endif /* CONFIG_HAS_DMA */
151
152/*
153 *
154 * ALSA generic memory management
155 *
156 */
157
158
159/**
160 * snd_dma_alloc_pages - allocate the buffer area according to the given type
161 * @type: the DMA buffer type
162 * @device: the device pointer
163 * @size: the buffer size to allocate
164 * @dmab: buffer allocation record to store the allocated data
165 *
166 * Calls the memory-allocator function for the corresponding
167 * buffer type.
168 *
169 * Return: Zero if the buffer with the given size is allocated successfully,
170 * otherwise a negative value on error.
171 */
172int snd_dma_alloc_pages(int type, struct device *device, size_t size,
173 struct snd_dma_buffer *dmab)
174{
175 if (WARN_ON(!size))
176 return -ENXIO;
177 if (WARN_ON(!dmab))
178 return -ENXIO;
179
180 dmab->dev.type = type;
181 dmab->dev.dev = device;
182 dmab->bytes = 0;
183 switch (type) {
184 case SNDRV_DMA_TYPE_CONTINUOUS:
185 dmab->area = snd_malloc_pages(size,
186 (__force gfp_t)(unsigned long)device);
187 dmab->addr = 0;
188 break;
189#ifdef CONFIG_HAS_DMA
190#ifdef CONFIG_GENERIC_ALLOCATOR
191 case SNDRV_DMA_TYPE_DEV_IRAM:
192 snd_malloc_dev_iram(dmab, size);
193 if (dmab->area)
194 break;
195 /* Internal memory might have limited size and no enough space,
196 * so if we fail to malloc, try to fetch memory traditionally.
197 */
198 dmab->dev.type = SNDRV_DMA_TYPE_DEV;
199#endif /* CONFIG_GENERIC_ALLOCATOR */
200 case SNDRV_DMA_TYPE_DEV:
201 dmab->area = snd_malloc_dev_pages(device, size, &dmab->addr);
202 break;
203#endif
204#ifdef CONFIG_SND_DMA_SGBUF
205 case SNDRV_DMA_TYPE_DEV_SG:
206 snd_malloc_sgbuf_pages(device, size, dmab, NULL);
207 break;
208#endif
209 default:
210 pr_err("snd-malloc: invalid device type %d\n", type);
211 dmab->area = NULL;
212 dmab->addr = 0;
213 return -ENXIO;
214 }
215 if (! dmab->area)
216 return -ENOMEM;
217 dmab->bytes = size;
218 return 0;
219}
220
221/**
222 * snd_dma_alloc_pages_fallback - allocate the buffer area according to the given type with fallback
223 * @type: the DMA buffer type
224 * @device: the device pointer
225 * @size: the buffer size to allocate
226 * @dmab: buffer allocation record to store the allocated data
227 *
228 * Calls the memory-allocator function for the corresponding
229 * buffer type. When no space is left, this function reduces the size and
230 * tries to allocate again. The size actually allocated is stored in
231 * res_size argument.
232 *
233 * Return: Zero if the buffer with the given size is allocated successfully,
234 * otherwise a negative value on error.
235 */
236int snd_dma_alloc_pages_fallback(int type, struct device *device, size_t size,
237 struct snd_dma_buffer *dmab)
238{
239 int err;
240
241 while ((err = snd_dma_alloc_pages(type, device, size, dmab)) < 0) {
242 size_t aligned_size;
243 if (err != -ENOMEM)
244 return err;
245 if (size <= PAGE_SIZE)
246 return -ENOMEM;
247 aligned_size = PAGE_SIZE << get_order(size);
248 if (size != aligned_size)
249 size = aligned_size;
250 else
251 size >>= 1;
252 }
253 if (! dmab->area)
254 return -ENOMEM;
255 return 0;
256}
257
258
259/**
260 * snd_dma_free_pages - release the allocated buffer
261 * @dmab: the buffer allocation record to release
262 *
263 * Releases the allocated buffer via snd_dma_alloc_pages().
264 */
265void snd_dma_free_pages(struct snd_dma_buffer *dmab)
266{
267 switch (dmab->dev.type) {
268 case SNDRV_DMA_TYPE_CONTINUOUS:
269 snd_free_pages(dmab->area, dmab->bytes);
270 break;
271#ifdef CONFIG_HAS_DMA
272#ifdef CONFIG_GENERIC_ALLOCATOR
273 case SNDRV_DMA_TYPE_DEV_IRAM:
274 snd_free_dev_iram(dmab);
275 break;
276#endif /* CONFIG_GENERIC_ALLOCATOR */
277 case SNDRV_DMA_TYPE_DEV:
278 snd_free_dev_pages(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
279 break;
280#endif
281#ifdef CONFIG_SND_DMA_SGBUF
282 case SNDRV_DMA_TYPE_DEV_SG:
283 snd_free_sgbuf_pages(dmab);
284 break;
285#endif
286 default:
287 pr_err("snd-malloc: invalid device type %d\n", dmab->dev.type);
288 }
289}
290
291/*
292 * exports
293 */
294EXPORT_SYMBOL(snd_dma_alloc_pages);
295EXPORT_SYMBOL(snd_dma_alloc_pages_fallback);
296EXPORT_SYMBOL(snd_dma_free_pages);
297
298EXPORT_SYMBOL(snd_malloc_pages);
299EXPORT_SYMBOL(snd_free_pages);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 * Takashi Iwai <tiwai@suse.de>
5 *
6 * Generic memory allocators
7 */
8
9#include <linux/slab.h>
10#include <linux/mm.h>
11#include <linux/dma-mapping.h>
12#include <linux/genalloc.h>
13#include <linux/vmalloc.h>
14#ifdef CONFIG_X86
15#include <asm/set_memory.h>
16#endif
17#include <sound/memalloc.h>
18#include "memalloc_local.h"
19
20static const struct snd_malloc_ops *snd_dma_get_ops(struct snd_dma_buffer *dmab);
21
22/* a cast to gfp flag from the dev pointer; for CONTINUOUS and VMALLOC types */
23static inline gfp_t snd_mem_get_gfp_flags(const struct snd_dma_buffer *dmab,
24 gfp_t default_gfp)
25{
26 if (!dmab->dev.dev)
27 return default_gfp;
28 else
29 return (__force gfp_t)(unsigned long)dmab->dev.dev;
30}
31
32static int __snd_dma_alloc_pages(struct snd_dma_buffer *dmab, size_t size)
33{
34 const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
35
36 if (WARN_ON_ONCE(!ops || !ops->alloc))
37 return -EINVAL;
38 return ops->alloc(dmab, size);
39}
40
41/**
42 * snd_dma_alloc_pages - allocate the buffer area according to the given type
43 * @type: the DMA buffer type
44 * @device: the device pointer
45 * @size: the buffer size to allocate
46 * @dmab: buffer allocation record to store the allocated data
47 *
48 * Calls the memory-allocator function for the corresponding
49 * buffer type.
50 *
51 * Return: Zero if the buffer with the given size is allocated successfully,
52 * otherwise a negative value on error.
53 */
54int snd_dma_alloc_pages(int type, struct device *device, size_t size,
55 struct snd_dma_buffer *dmab)
56{
57 int err;
58
59 if (WARN_ON(!size))
60 return -ENXIO;
61 if (WARN_ON(!dmab))
62 return -ENXIO;
63
64 size = PAGE_ALIGN(size);
65 dmab->dev.type = type;
66 dmab->dev.dev = device;
67 dmab->bytes = 0;
68 dmab->area = NULL;
69 dmab->addr = 0;
70 dmab->private_data = NULL;
71 err = __snd_dma_alloc_pages(dmab, size);
72 if (err < 0)
73 return err;
74 if (!dmab->area)
75 return -ENOMEM;
76 dmab->bytes = size;
77 return 0;
78}
79EXPORT_SYMBOL(snd_dma_alloc_pages);
80
81/**
82 * snd_dma_alloc_pages_fallback - allocate the buffer area according to the given type with fallback
83 * @type: the DMA buffer type
84 * @device: the device pointer
85 * @size: the buffer size to allocate
86 * @dmab: buffer allocation record to store the allocated data
87 *
88 * Calls the memory-allocator function for the corresponding
89 * buffer type. When no space is left, this function reduces the size and
90 * tries to allocate again. The size actually allocated is stored in
91 * res_size argument.
92 *
93 * Return: Zero if the buffer with the given size is allocated successfully,
94 * otherwise a negative value on error.
95 */
96int snd_dma_alloc_pages_fallback(int type, struct device *device, size_t size,
97 struct snd_dma_buffer *dmab)
98{
99 int err;
100
101 while ((err = snd_dma_alloc_pages(type, device, size, dmab)) < 0) {
102 if (err != -ENOMEM)
103 return err;
104 if (size <= PAGE_SIZE)
105 return -ENOMEM;
106 size >>= 1;
107 size = PAGE_SIZE << get_order(size);
108 }
109 if (! dmab->area)
110 return -ENOMEM;
111 return 0;
112}
113EXPORT_SYMBOL(snd_dma_alloc_pages_fallback);
114
115/**
116 * snd_dma_free_pages - release the allocated buffer
117 * @dmab: the buffer allocation record to release
118 *
119 * Releases the allocated buffer via snd_dma_alloc_pages().
120 */
121void snd_dma_free_pages(struct snd_dma_buffer *dmab)
122{
123 const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
124
125 if (ops && ops->free)
126 ops->free(dmab);
127}
128EXPORT_SYMBOL(snd_dma_free_pages);
129
130/**
131 * snd_dma_buffer_mmap - perform mmap of the given DMA buffer
132 * @dmab: buffer allocation information
133 * @area: VM area information
134 */
135int snd_dma_buffer_mmap(struct snd_dma_buffer *dmab,
136 struct vm_area_struct *area)
137{
138 const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
139
140 if (ops && ops->mmap)
141 return ops->mmap(dmab, area);
142 else
143 return -ENOENT;
144}
145EXPORT_SYMBOL(snd_dma_buffer_mmap);
146
147/**
148 * snd_sgbuf_get_addr - return the physical address at the corresponding offset
149 * @dmab: buffer allocation information
150 * @offset: offset in the ring buffer
151 */
152dma_addr_t snd_sgbuf_get_addr(struct snd_dma_buffer *dmab, size_t offset)
153{
154 const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
155
156 if (ops && ops->get_addr)
157 return ops->get_addr(dmab, offset);
158 else
159 return dmab->addr + offset;
160}
161EXPORT_SYMBOL(snd_sgbuf_get_addr);
162
163/**
164 * snd_sgbuf_get_page - return the physical page at the corresponding offset
165 * @dmab: buffer allocation information
166 * @offset: offset in the ring buffer
167 */
168struct page *snd_sgbuf_get_page(struct snd_dma_buffer *dmab, size_t offset)
169{
170 const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
171
172 if (ops && ops->get_page)
173 return ops->get_page(dmab, offset);
174 else
175 return virt_to_page(dmab->area + offset);
176}
177EXPORT_SYMBOL(snd_sgbuf_get_page);
178
179/**
180 * snd_sgbuf_get_chunk_size - compute the max chunk size with continuous pages
181 * on sg-buffer
182 * @dmab: buffer allocation information
183 * @ofs: offset in the ring buffer
184 * @size: the requested size
185 */
186unsigned int snd_sgbuf_get_chunk_size(struct snd_dma_buffer *dmab,
187 unsigned int ofs, unsigned int size)
188{
189 const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
190
191 if (ops && ops->get_chunk_size)
192 return ops->get_chunk_size(dmab, ofs, size);
193 else
194 return size;
195}
196EXPORT_SYMBOL(snd_sgbuf_get_chunk_size);
197
198/*
199 * Continuous pages allocator
200 */
201static int snd_dma_continuous_alloc(struct snd_dma_buffer *dmab, size_t size)
202{
203 gfp_t gfp = snd_mem_get_gfp_flags(dmab, GFP_KERNEL);
204
205 dmab->area = alloc_pages_exact(size, gfp);
206 return 0;
207}
208
209static void snd_dma_continuous_free(struct snd_dma_buffer *dmab)
210{
211 free_pages_exact(dmab->area, dmab->bytes);
212}
213
214static int snd_dma_continuous_mmap(struct snd_dma_buffer *dmab,
215 struct vm_area_struct *area)
216{
217 return remap_pfn_range(area, area->vm_start,
218 page_to_pfn(virt_to_page(dmab->area)),
219 area->vm_end - area->vm_start,
220 area->vm_page_prot);
221}
222
223static const struct snd_malloc_ops snd_dma_continuous_ops = {
224 .alloc = snd_dma_continuous_alloc,
225 .free = snd_dma_continuous_free,
226 .mmap = snd_dma_continuous_mmap,
227};
228
229/*
230 * VMALLOC allocator
231 */
232static int snd_dma_vmalloc_alloc(struct snd_dma_buffer *dmab, size_t size)
233{
234 gfp_t gfp = snd_mem_get_gfp_flags(dmab, GFP_KERNEL | __GFP_HIGHMEM);
235
236 dmab->area = __vmalloc(size, gfp);
237 return 0;
238}
239
240static void snd_dma_vmalloc_free(struct snd_dma_buffer *dmab)
241{
242 vfree(dmab->area);
243}
244
245static int snd_dma_vmalloc_mmap(struct snd_dma_buffer *dmab,
246 struct vm_area_struct *area)
247{
248 return remap_vmalloc_range(area, dmab->area, 0);
249}
250
251static dma_addr_t snd_dma_vmalloc_get_addr(struct snd_dma_buffer *dmab,
252 size_t offset)
253{
254 return page_to_phys(vmalloc_to_page(dmab->area + offset)) +
255 offset % PAGE_SIZE;
256}
257
258static struct page *snd_dma_vmalloc_get_page(struct snd_dma_buffer *dmab,
259 size_t offset)
260{
261 return vmalloc_to_page(dmab->area + offset);
262}
263
264static unsigned int
265snd_dma_vmalloc_get_chunk_size(struct snd_dma_buffer *dmab,
266 unsigned int ofs, unsigned int size)
267{
268 ofs %= PAGE_SIZE;
269 size += ofs;
270 if (size > PAGE_SIZE)
271 size = PAGE_SIZE;
272 return size - ofs;
273}
274
275static const struct snd_malloc_ops snd_dma_vmalloc_ops = {
276 .alloc = snd_dma_vmalloc_alloc,
277 .free = snd_dma_vmalloc_free,
278 .mmap = snd_dma_vmalloc_mmap,
279 .get_addr = snd_dma_vmalloc_get_addr,
280 .get_page = snd_dma_vmalloc_get_page,
281 .get_chunk_size = snd_dma_vmalloc_get_chunk_size,
282};
283
284#ifdef CONFIG_HAS_DMA
285/*
286 * IRAM allocator
287 */
288#ifdef CONFIG_GENERIC_ALLOCATOR
289static int snd_dma_iram_alloc(struct snd_dma_buffer *dmab, size_t size)
290{
291 struct device *dev = dmab->dev.dev;
292 struct gen_pool *pool;
293
294 if (dev->of_node) {
295 pool = of_gen_pool_get(dev->of_node, "iram", 0);
296 /* Assign the pool into private_data field */
297 dmab->private_data = pool;
298
299 dmab->area = gen_pool_dma_alloc_align(pool, size, &dmab->addr,
300 PAGE_SIZE);
301 if (dmab->area)
302 return 0;
303 }
304
305 /* Internal memory might have limited size and no enough space,
306 * so if we fail to malloc, try to fetch memory traditionally.
307 */
308 dmab->dev.type = SNDRV_DMA_TYPE_DEV;
309 return __snd_dma_alloc_pages(dmab, size);
310}
311
312static void snd_dma_iram_free(struct snd_dma_buffer *dmab)
313{
314 struct gen_pool *pool = dmab->private_data;
315
316 if (pool && dmab->area)
317 gen_pool_free(pool, (unsigned long)dmab->area, dmab->bytes);
318}
319
320static int snd_dma_iram_mmap(struct snd_dma_buffer *dmab,
321 struct vm_area_struct *area)
322{
323 area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
324 return remap_pfn_range(area, area->vm_start,
325 dmab->addr >> PAGE_SHIFT,
326 area->vm_end - area->vm_start,
327 area->vm_page_prot);
328}
329
330static const struct snd_malloc_ops snd_dma_iram_ops = {
331 .alloc = snd_dma_iram_alloc,
332 .free = snd_dma_iram_free,
333 .mmap = snd_dma_iram_mmap,
334};
335#endif /* CONFIG_GENERIC_ALLOCATOR */
336
337/*
338 * Coherent device pages allocator
339 */
340static int snd_dma_dev_alloc(struct snd_dma_buffer *dmab, size_t size)
341{
342 gfp_t gfp_flags;
343
344 gfp_flags = GFP_KERNEL
345 | __GFP_COMP /* compound page lets parts be mapped */
346 | __GFP_NORETRY /* don't trigger OOM-killer */
347 | __GFP_NOWARN; /* no stack trace print - this call is non-critical */
348 dmab->area = dma_alloc_coherent(dmab->dev.dev, size, &dmab->addr,
349 gfp_flags);
350#ifdef CONFIG_X86
351 if (dmab->area && dmab->dev.type == SNDRV_DMA_TYPE_DEV_UC)
352 set_memory_wc((unsigned long)dmab->area,
353 PAGE_ALIGN(size) >> PAGE_SHIFT);
354#endif
355 return 0;
356}
357
358static void snd_dma_dev_free(struct snd_dma_buffer *dmab)
359{
360#ifdef CONFIG_X86
361 if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_UC)
362 set_memory_wb((unsigned long)dmab->area,
363 PAGE_ALIGN(dmab->bytes) >> PAGE_SHIFT);
364#endif
365 dma_free_coherent(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
366}
367
368static int snd_dma_dev_mmap(struct snd_dma_buffer *dmab,
369 struct vm_area_struct *area)
370{
371 return dma_mmap_coherent(dmab->dev.dev, area,
372 dmab->area, dmab->addr, dmab->bytes);
373}
374
375static const struct snd_malloc_ops snd_dma_dev_ops = {
376 .alloc = snd_dma_dev_alloc,
377 .free = snd_dma_dev_free,
378 .mmap = snd_dma_dev_mmap,
379};
380#endif /* CONFIG_HAS_DMA */
381
382/*
383 * Entry points
384 */
385static const struct snd_malloc_ops *dma_ops[] = {
386 [SNDRV_DMA_TYPE_CONTINUOUS] = &snd_dma_continuous_ops,
387 [SNDRV_DMA_TYPE_VMALLOC] = &snd_dma_vmalloc_ops,
388#ifdef CONFIG_HAS_DMA
389 [SNDRV_DMA_TYPE_DEV] = &snd_dma_dev_ops,
390 [SNDRV_DMA_TYPE_DEV_UC] = &snd_dma_dev_ops,
391#ifdef CONFIG_GENERIC_ALLOCATOR
392 [SNDRV_DMA_TYPE_DEV_IRAM] = &snd_dma_iram_ops,
393#endif /* CONFIG_GENERIC_ALLOCATOR */
394#endif /* CONFIG_HAS_DMA */
395#ifdef CONFIG_SND_DMA_SGBUF
396 [SNDRV_DMA_TYPE_DEV_SG] = &snd_dma_sg_ops,
397 [SNDRV_DMA_TYPE_DEV_UC_SG] = &snd_dma_sg_ops,
398#endif
399};
400
401static const struct snd_malloc_ops *snd_dma_get_ops(struct snd_dma_buffer *dmab)
402{
403 if (WARN_ON_ONCE(dmab->dev.type <= SNDRV_DMA_TYPE_UNKNOWN ||
404 dmab->dev.type >= ARRAY_SIZE(dma_ops)))
405 return NULL;
406 return dma_ops[dmab->dev.type];
407}