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authorImre Deak <imre.deak@nokia.com>2006-02-17 10:02:18 -0800
committerGreg Kroah-Hartman <gregkh@suse.de>2006-05-16 14:33:56 -0700
commit4cff33f94fefcce1b3c01a9d1da6bb85fe3cbdfa (patch)
tree0ef6066c4f2c0225517a6402bb04f4b4d56afd4d /include/linux/spi/spi_bitbang.h
parent716f8954fb3029ca2df52a986b60af8d06f093ee (diff)
[PATCH] SPI: per-transfer overrides for wordsize and clocking
Some protocols (like one for some bitmap displays) require different clock speed or word size settings for each transfer in an SPI message. This adds those parameters to struct spi_transfer. They are to be used when they are nonzero; otherwise the defaults from spi_device are to be used. The patch also adds a setup_transfer callback to spi_bitbang, uses it for messages that use those overrides, and implements it so that the pure bitbanging code can help resolve any questions about how it should work. Signed-off-by: Imre Deak <imre.deak@nokia.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'include/linux/spi/spi_bitbang.h')
-rw-r--r--include/linux/spi/spi_bitbang.h6
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/spi/spi_bitbang.h b/include/linux/spi/spi_bitbang.h
index c961fe9bf3e..c954557b757 100644
--- a/include/linux/spi/spi_bitbang.h
+++ b/include/linux/spi/spi_bitbang.h
@@ -30,6 +30,12 @@ struct spi_bitbang {
struct spi_master *master;
+ /* setup_transfer() changes clock and/or wordsize to match settings
+ * for this transfer; zeroes restore defaults from spi_device.
+ */
+ int (*setup_transfer)(struct spi_device *spi,
+ struct spi_transfer *t);
+
void (*chipselect)(struct spi_device *spi, int is_on);
#define BITBANG_CS_ACTIVE 1 /* normally nCS, active low */
#define BITBANG_CS_INACTIVE 0