diff options
Diffstat (limited to 'include/bouncebuf.h')
-rw-r--r-- | include/bouncebuf.h | 47 |
1 files changed, 24 insertions, 23 deletions
diff --git a/include/bouncebuf.h b/include/bouncebuf.h index 31021c5b85..707b588c73 100644 --- a/include/bouncebuf.h +++ b/include/bouncebuf.h @@ -25,6 +25,8 @@ #ifndef __INCLUDE_BOUNCEBUF_H__ #define __INCLUDE_BOUNCEBUF_H__ +#include <linux/types.h> + /* * GEN_BB_READ -- Data are read from the buffer eg. by DMA hardware. * The source buffer is copied into the bounce buffer (if unaligned, otherwise @@ -51,37 +53,36 @@ */ #define GEN_BB_RW (GEN_BB_READ | GEN_BB_WRITE) -#ifdef CONFIG_BOUNCE_BUFFER +struct bounce_buffer { + /* Copy of data parameter passed to start() */ + void *user_buffer; + /* + * DMA-aligned buffer. This field is always set to the value that + * should be used for DMA; either equal to .user_buffer, or to a + * freshly allocated aligned buffer. + */ + void *bounce_buffer; + /* Copy of len parameter passed to start() */ + size_t len; + /* DMA-aligned buffer length */ + size_t len_aligned; + /* Copy of flags parameter passed to start() */ + unsigned int flags; +}; + /** * bounce_buffer_start() -- Start the bounce buffer session + * state: stores state passed between bounce_buffer_{start,stop} * data: pointer to buffer to be aligned * len: length of the buffer - * backup: pointer to backup buffer (the original value is stored here if - * needed * flags: flags describing the transaction, see above. */ -int bounce_buffer_start(void **data, size_t len, void **backup, uint8_t flags); +int bounce_buffer_start(struct bounce_buffer *state, void *data, + size_t len, unsigned int flags); /** * bounce_buffer_stop() -- Finish the bounce buffer session - * data: pointer to buffer that was aligned - * len: length of the buffer - * backup: pointer to backup buffer (the original value is stored here if - * needed - * flags: flags describing the transaction, see above. + * state: stores state passed between bounce_buffer_{start,stop} */ -int bounce_buffer_stop(void **data, size_t len, void **backup, uint8_t flags); -#else -static inline int bounce_buffer_start(void **data, size_t len, void **backup, - uint8_t flags) -{ - return 0; -} - -static inline int bounce_buffer_stop(void **data, size_t len, void **backup, - uint8_t flags) -{ - return 0; -} -#endif +int bounce_buffer_stop(struct bounce_buffer *state); #endif |