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authorMartin Sperl <kernel@martin.sperl.org>2015-12-14 18:20:20 +0300
committerMark Brown <broonie@kernel.org>2016-02-09 22:32:07 +0300
commitd9f1212272818420fcde611a940c1ad611a8b785 (patch)
tree0799bc9b7950503331bfbb384fbda85a427b9eeb /include/linux
parent523baf5a0609690cb742b3662b7ccac0ea0b2ef2 (diff)
downloadlinux-d9f1212272818420fcde611a940c1ad611a8b785.tar.xz
spi: core: add spi_split_transfers_maxsize
Add spi_split_transfers_maxsize method that splits spi_transfers transparently into multiple transfers that are below the given max-size. This makes use of the spi_res framework via spi_replace_transfers to allocate/free the extra transfers as well as reverting back the changes applied while processing the spi_message. Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'include/linux')
-rw-r--r--include/linux/spi/spi.h15
1 files changed, 15 insertions, 0 deletions
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index d71385756fee..3c02b4d06268 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -53,6 +53,10 @@ extern struct bus_type spi_bus_type;
*
* @transfer_bytes_histo:
* transfer bytes histogramm
+ *
+ * @transfers_split_maxsize:
+ * number of transfers that have been split because of
+ * maxsize limit
*/
struct spi_statistics {
spinlock_t lock; /* lock for the whole structure */
@@ -72,6 +76,8 @@ struct spi_statistics {
#define SPI_STATISTICS_HISTO_SIZE 17
unsigned long transfer_bytes_histo[SPI_STATISTICS_HISTO_SIZE];
+
+ unsigned long transfers_split_maxsize;
};
void spi_statistics_add_transfer_stats(struct spi_statistics *stats,
@@ -935,6 +941,15 @@ extern struct spi_replaced_transfers *spi_replace_transfers(
/*---------------------------------------------------------------------------*/
+/* SPI transfer transformation methods */
+
+extern int spi_split_transfers_maxsize(struct spi_master *master,
+ struct spi_message *msg,
+ size_t maxsize,
+ gfp_t gfp);
+
+/*---------------------------------------------------------------------------*/
+
/* All these synchronous SPI transfer routines are utilities layered
* over the core async transfer primitive. Here, "synchronous" means
* they will sleep uninterruptibly until the async transfer completes.