/dev/spidevB.C interface

Add a filesystem API for <linux/spi/spi.h> stack.  The initial version of
this interface is purely synchronous.

dbrownell@users.sourceforge.net:

 Cleaned up, bugfixed; much simplified; added preliminary documentation.

 Works with mdev given CONFIG_SYSFS_DEPRECATED; and presumably udev.

 Updated SPI_IOC_MESSAGE ioctl to full spi_message semantics, supporting
 groups of one or more transfers (each of which may be full duplex if
 desired).

 This is marked as EXPERIMENTAL with an explicit disclaimer that the API
 (notably the ioctls) is subject to change.

Signed-off-by: Andrea Paterniani <a.paterniani@swapp-eng.it>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 4a012d9acbff..584ed9f74700 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -159,6 +159,15 @@ config SPI_AT25
           This driver can also be built as a module.  If so, the module
           will be called at25.
 
+config SPI_SPIDEV
+        tristate "User mode SPI device driver support"
+        depends on SPI_MASTER && EXPERIMENTAL
+        help
+          This supports user mode SPI protocol drivers.
+
+          Note that this application programming interface is EXPERIMENTAL
+          and hence SUBJECT TO CHANGE WITHOUT NOTICE while it stabilizes.
+
 #
 # Add new SPI protocol masters in alphabetical order above this line
 #