[PATCH V2 1/3] arm: dma mapping: Export dma ops functions

Gregory CLEMENT gregory.clement at free-electrons.com
Fri Nov 16 04:44:58 EST 2012


Expose the DMA operations functions. Until now only the dma_ops
structs in a whole or some dma operation were exposed. This patch
exposes all the dma coherents and non-coherents operations. They can
be reused when an architecture or driver need to create its own set of
dma_operation.

Signed-off-by: Gregory CLEMENT <gregory.clement at free-electrons.com>
---
 arch/arm/include/asm/dma-mapping.h |   62 ++++++++++++++++++++++++++++++++++++
 arch/arm/mm/dma-mapping.c          |   36 +++++----------------
 2 files changed, 70 insertions(+), 28 deletions(-)

diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h
index 2300484..f940a10 100644
--- a/arch/arm/include/asm/dma-mapping.h
+++ b/arch/arm/include/asm/dma-mapping.h
@@ -112,6 +112,60 @@ static inline void dma_free_noncoherent(struct device *dev, size_t size,
 extern int dma_supported(struct device *dev, u64 mask);
 
 /**
+ * arm_dma_map_page - map a portion of a page for streaming DMA
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @page: page that buffer resides in
+ * @offset: offset into page for start of buffer
+ * @size: size of buffer to map
+ * @dir: DMA transfer direction
+ *
+ * Ensure that any data held in the cache is appropriately discarded
+ * or written back.
+ *
+ * The device owns this memory once this call has completed.  The CPU
+ * can regain ownership by calling dma_unmap_page().
+ */
+extern dma_addr_t arm_dma_map_page(struct device *dev, struct page *page,
+				    unsigned long offset, size_t size,
+				    enum dma_data_direction dir,
+				    struct dma_attrs *attrs);
+
+extern dma_addr_t arm_coherent_dma_map_page(struct device *dev,
+					    struct page *page,
+					    unsigned long offset, size_t size,
+					    enum dma_data_direction dir,
+					    struct dma_attrs *attrs);
+
+/**
+ * arm_dma_unmap_page - unmap a buffer previously mapped through dma_map_page()
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @handle: DMA address of buffer
+ * @size: size of buffer (same as passed to dma_map_page)
+ * @dir: DMA transfer direction (same as passed to dma_map_page)
+ *
+ * Unmap a page streaming mode DMA translation.  The handle and size
+ * must match what was provided in the previous dma_map_page() call.
+ * All other usages are undefined.
+ *
+ * After this call, reads by the CPU to the buffer are guaranteed to see
+ * whatever the device wrote there.
+ */
+extern void arm_dma_unmap_page(struct device *dev, dma_addr_t handle,
+				size_t size, enum dma_data_direction dir,
+				struct dma_attrs *attrs);
+
+extern void arm_dma_sync_single_for_cpu(struct device *dev,
+					dma_addr_t handle, size_t size,
+					enum dma_data_direction dir);
+
+extern void arm_dma_sync_single_for_device(struct device *dev,
+					dma_addr_t handle, size_t size,
+					enum dma_data_direction dir);
+
+extern int arm_dma_set_mask(struct device *dev, u64 dma_mask);
+
+
+/**
  * arm_dma_alloc - allocate consistent memory for DMA
  * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
  * @size: required memory size
@@ -125,6 +179,10 @@ extern int dma_supported(struct device *dev, u64 mask);
 extern void *arm_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
 			   gfp_t gfp, struct dma_attrs *attrs);
 
+extern void *arm_coherent_dma_alloc(struct device *dev, size_t size,
+				    dma_addr_t *handle, gfp_t gfp,
+				    struct dma_attrs *attrs);
+
 #define dma_alloc_coherent(d, s, h, f) dma_alloc_attrs(d, s, h, f, NULL)
 
 static inline void *dma_alloc_attrs(struct device *dev, size_t size,
@@ -157,6 +215,10 @@ static inline void *dma_alloc_attrs(struct device *dev, size_t size,
 extern void arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
 			 dma_addr_t handle, struct dma_attrs *attrs);
 
+extern void arm_coherent_dma_free(struct device *dev, size_t size,
+				    void *cpu_addr, dma_addr_t handle,
+				    struct dma_attrs *attrs);
+
 #define dma_free_coherent(d, s, c, h) dma_free_attrs(d, s, c, h, NULL)
 
 static inline void dma_free_attrs(struct device *dev, size_t size,
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 58bc3e4..5b60ee6 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -56,20 +56,13 @@ static void __dma_page_dev_to_cpu(struct page *, unsigned long,
 		size_t, enum dma_data_direction);
 
 /**
- * arm_dma_map_page - map a portion of a page for streaming DMA
- * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
- * @page: page that buffer resides in
- * @offset: offset into page for start of buffer
- * @size: size of buffer to map
- * @dir: DMA transfer direction
- *
  * Ensure that any data held in the cache is appropriately discarded
  * or written back.
  *
  * The device owns this memory once this call has completed.  The CPU
  * can regain ownership by calling dma_unmap_page().
  */
-static dma_addr_t arm_dma_map_page(struct device *dev, struct page *page,
+dma_addr_t arm_dma_map_page(struct device *dev, struct page *page,
 	     unsigned long offset, size_t size, enum dma_data_direction dir,
 	     struct dma_attrs *attrs)
 {
@@ -78,7 +71,7 @@ static dma_addr_t arm_dma_map_page(struct device *dev, struct page *page,
 	return pfn_to_dma(dev, page_to_pfn(page)) + offset;
 }
 
-static dma_addr_t arm_coherent_dma_map_page(struct device *dev, struct page *page,
+dma_addr_t arm_coherent_dma_map_page(struct device *dev, struct page *page,
 	     unsigned long offset, size_t size, enum dma_data_direction dir,
 	     struct dma_attrs *attrs)
 {
@@ -86,12 +79,6 @@ static dma_addr_t arm_coherent_dma_map_page(struct device *dev, struct page *pag
 }
 
 /**
- * arm_dma_unmap_page - unmap a buffer previously mapped through dma_map_page()
- * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
- * @handle: DMA address of buffer
- * @size: size of buffer (same as passed to dma_map_page)
- * @dir: DMA transfer direction (same as passed to dma_map_page)
- *
  * Unmap a page streaming mode DMA translation.  The handle and size
  * must match what was provided in the previous dma_map_page() call.
  * All other usages are undefined.
@@ -99,7 +86,7 @@ static dma_addr_t arm_coherent_dma_map_page(struct device *dev, struct page *pag
  * After this call, reads by the CPU to the buffer are guaranteed to see
  * whatever the device wrote there.
  */
-static void arm_dma_unmap_page(struct device *dev, dma_addr_t handle,
+void arm_dma_unmap_page(struct device *dev, dma_addr_t handle,
 		size_t size, enum dma_data_direction dir,
 		struct dma_attrs *attrs)
 {
@@ -108,7 +95,7 @@ static void arm_dma_unmap_page(struct device *dev, dma_addr_t handle,
 				      handle & ~PAGE_MASK, size, dir);
 }
 
-static void arm_dma_sync_single_for_cpu(struct device *dev,
+void arm_dma_sync_single_for_cpu(struct device *dev,
 		dma_addr_t handle, size_t size, enum dma_data_direction dir)
 {
 	unsigned int offset = handle & (PAGE_SIZE - 1);
@@ -116,7 +103,7 @@ static void arm_dma_sync_single_for_cpu(struct device *dev,
 	__dma_page_dev_to_cpu(page, offset, size, dir);
 }
 
-static void arm_dma_sync_single_for_device(struct device *dev,
+void arm_dma_sync_single_for_device(struct device *dev,
 		dma_addr_t handle, size_t size, enum dma_data_direction dir)
 {
 	unsigned int offset = handle & (PAGE_SIZE - 1);
@@ -124,8 +111,6 @@ static void arm_dma_sync_single_for_device(struct device *dev,
 	__dma_page_cpu_to_dev(page, offset, size, dir);
 }
 
-static int arm_dma_set_mask(struct device *dev, u64 dma_mask);
-
 struct dma_map_ops arm_dma_ops = {
 	.alloc			= arm_dma_alloc,
 	.free			= arm_dma_free,
@@ -143,11 +128,6 @@ struct dma_map_ops arm_dma_ops = {
 };
 EXPORT_SYMBOL(arm_dma_ops);
 
-static void *arm_coherent_dma_alloc(struct device *dev, size_t size,
-	dma_addr_t *handle, gfp_t gfp, struct dma_attrs *attrs);
-static void arm_coherent_dma_free(struct device *dev, size_t size, void *cpu_addr,
-				  dma_addr_t handle, struct dma_attrs *attrs);
-
 struct dma_map_ops arm_coherent_dma_ops = {
 	.alloc			= arm_coherent_dma_alloc,
 	.free			= arm_coherent_dma_free,
@@ -672,7 +652,7 @@ void *arm_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
 			   __builtin_return_address(0));
 }
 
-static void *arm_coherent_dma_alloc(struct device *dev, size_t size,
+void *arm_coherent_dma_alloc(struct device *dev, size_t size,
 	dma_addr_t *handle, gfp_t gfp, struct dma_attrs *attrs)
 {
 	pgprot_t prot = __get_dma_pgprot(attrs, pgprot_kernel);
@@ -751,7 +731,7 @@ void arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
 	__arm_dma_free(dev, size, cpu_addr, handle, attrs, false);
 }
 
-static void arm_coherent_dma_free(struct device *dev, size_t size, void *cpu_addr,
+void arm_coherent_dma_free(struct device *dev, size_t size, void *cpu_addr,
 				  dma_addr_t handle, struct dma_attrs *attrs)
 {
 	__arm_dma_free(dev, size, cpu_addr, handle, attrs, true);
@@ -971,7 +951,7 @@ int dma_supported(struct device *dev, u64 mask)
 }
 EXPORT_SYMBOL(dma_supported);
 
-static int arm_dma_set_mask(struct device *dev, u64 dma_mask)
+int arm_dma_set_mask(struct device *dev, u64 dma_mask)
 {
 	if (!dev->dma_mask || !dma_supported(dev, dma_mask))
 		return -EIO;
-- 
1.7.9.5




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