1/*
  2 * drivers/base/dma-mapping.c - arch-independent dma-mapping routines
  3 *
  4 * Copyright (c) 2006  SUSE Linux Products GmbH
  5 * Copyright (c) 2006  Tejun Heo <teheo@suse.de>
  6 *
  7 * This file is released under the GPLv2.
  8 */
  9
 10#include <linux/dma-mapping.h>
 11#include <linux/export.h>
 12#include <linux/gfp.h>
 13
 14/*
 15 * Managed DMA API
 16 */
 17struct dma_devres {
 18	size_t		size;
 19	void		*vaddr;
 20	dma_addr_t	dma_handle;
 21};
 22
 23static void dmam_coherent_release(struct device *dev, void *res)
 24{
 25	struct dma_devres *this = res;
 26
 27	dma_free_coherent(dev, this->size, this->vaddr, this->dma_handle);
 28}
 29
 30static void dmam_noncoherent_release(struct device *dev, void *res)
 31{
 32	struct dma_devres *this = res;
 33
 34	dma_free_noncoherent(dev, this->size, this->vaddr, this->dma_handle);
 35}
 36
 37static int dmam_match(struct device *dev, void *res, void *match_data)
 38{
 39	struct dma_devres *this = res, *match = match_data;
 40
 41	if (this->vaddr == match->vaddr) {
 42		WARN_ON(this->size != match->size ||
 43			this->dma_handle != match->dma_handle);
 44		return 1;
 45	}
 46	return 0;
 47}
 48
 49/**
 50 * dmam_alloc_coherent - Managed dma_alloc_coherent()
 51 * @dev: Device to allocate coherent memory for
 52 * @size: Size of allocation
 53 * @dma_handle: Out argument for allocated DMA handle
 54 * @gfp: Allocation flags
 55 *
 56 * Managed dma_alloc_coherent().  Memory allocated using this function
 57 * will be automatically released on driver detach.
 58 *
 59 * RETURNS:
 60 * Pointer to allocated memory on success, NULL on failure.
 61 */
 62void * dmam_alloc_coherent(struct device *dev, size_t size,
 63			   dma_addr_t *dma_handle, gfp_t gfp)
 64{
 65	struct dma_devres *dr;
 66	void *vaddr;
 67
 68	dr = devres_alloc(dmam_coherent_release, sizeof(*dr), gfp);
 69	if (!dr)
 70		return NULL;
 71
 72	vaddr = dma_alloc_coherent(dev, size, dma_handle, gfp);
 73	if (!vaddr) {
 74		devres_free(dr);
 75		return NULL;
 76	}
 77
 78	dr->vaddr = vaddr;
 79	dr->dma_handle = *dma_handle;
 80	dr->size = size;
 81
 82	devres_add(dev, dr);
 83
 84	return vaddr;
 85}
 86EXPORT_SYMBOL(dmam_alloc_coherent);
 87
 88/**
 89 * dmam_free_coherent - Managed dma_free_coherent()
 90 * @dev: Device to free coherent memory for
 91 * @size: Size of allocation
 92 * @vaddr: Virtual address of the memory to free
 93 * @dma_handle: DMA handle of the memory to free
 94 *
 95 * Managed dma_free_coherent().
 96 */
 97void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
 98			dma_addr_t dma_handle)
 99{
100	struct dma_devres match_data = { size, vaddr, dma_handle };
101
102	dma_free_coherent(dev, size, vaddr, dma_handle);
103	WARN_ON(devres_destroy(dev, dmam_coherent_release, dmam_match,
104			       &match_data));
105}
106EXPORT_SYMBOL(dmam_free_coherent);
107
108/**
109 * dmam_alloc_non_coherent - Managed dma_alloc_non_coherent()
110 * @dev: Device to allocate non_coherent memory for
111 * @size: Size of allocation
112 * @dma_handle: Out argument for allocated DMA handle
113 * @gfp: Allocation flags
114 *
115 * Managed dma_alloc_non_coherent().  Memory allocated using this
116 * function will be automatically released on driver detach.
117 *
118 * RETURNS:
119 * Pointer to allocated memory on success, NULL on failure.
120 */
121void *dmam_alloc_noncoherent(struct device *dev, size_t size,
122			     dma_addr_t *dma_handle, gfp_t gfp)
123{
124	struct dma_devres *dr;
125	void *vaddr;
126
127	dr = devres_alloc(dmam_noncoherent_release, sizeof(*dr), gfp);
128	if (!dr)
129		return NULL;
130
131	vaddr = dma_alloc_noncoherent(dev, size, dma_handle, gfp);
132	if (!vaddr) {
133		devres_free(dr);
134		return NULL;
135	}
136
137	dr->vaddr = vaddr;
138	dr->dma_handle = *dma_handle;
139	dr->size = size;
140
141	devres_add(dev, dr);
142
143	return vaddr;
144}
145EXPORT_SYMBOL(dmam_alloc_noncoherent);
146
147/**
148 * dmam_free_coherent - Managed dma_free_noncoherent()
149 * @dev: Device to free noncoherent memory for
150 * @size: Size of allocation
151 * @vaddr: Virtual address of the memory to free
152 * @dma_handle: DMA handle of the memory to free
153 *
154 * Managed dma_free_noncoherent().
155 */
156void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
157			   dma_addr_t dma_handle)
158{
159	struct dma_devres match_data = { size, vaddr, dma_handle };
160
161	dma_free_noncoherent(dev, size, vaddr, dma_handle);
162	WARN_ON(!devres_destroy(dev, dmam_noncoherent_release, dmam_match,
163				&match_data));
164}
165EXPORT_SYMBOL(dmam_free_noncoherent);
166
167#ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
168
169static void dmam_coherent_decl_release(struct device *dev, void *res)
170{
171	dma_release_declared_memory(dev);
172}
173
174/**
175 * dmam_declare_coherent_memory - Managed dma_declare_coherent_memory()
176 * @dev: Device to declare coherent memory for
177 * @bus_addr: Bus address of coherent memory to be declared
178 * @device_addr: Device address of coherent memory to be declared
179 * @size: Size of coherent memory to be declared
180 * @flags: Flags
181 *
182 * Managed dma_declare_coherent_memory().
183 *
184 * RETURNS:
185 * 0 on success, -errno on failure.
186 */
187int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
188				 dma_addr_t device_addr, size_t size, int flags)
189{
190	void *res;
191	int rc;
192
193	res = devres_alloc(dmam_coherent_decl_release, 0, GFP_KERNEL);
194	if (!res)
195		return -ENOMEM;
196
197	rc = dma_declare_coherent_memory(dev, bus_addr, device_addr, size,
198					 flags);
199	if (rc == 0)
200		devres_add(dev, res);
201	else
202		devres_free(res);
203
204	return rc;
205}
206EXPORT_SYMBOL(dmam_declare_coherent_memory);
207
208/**
209 * dmam_release_declared_memory - Managed dma_release_declared_memory().
210 * @dev: Device to release declared coherent memory for
211 *
212 * Managed dmam_release_declared_memory().
213 */
214void dmam_release_declared_memory(struct device *dev)
215{
216	WARN_ON(devres_destroy(dev, dmam_coherent_decl_release, NULL, NULL));
217}
218EXPORT_SYMBOL(dmam_release_declared_memory);
219
220#endif