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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/include/linux/spi/spi_bitbang.h
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/include/linux/spi/spi_bitbang.h')
-rw-r--r--kernel/include/linux/spi/spi_bitbang.h47
1 files changed, 47 insertions, 0 deletions
diff --git a/kernel/include/linux/spi/spi_bitbang.h b/kernel/include/linux/spi/spi_bitbang.h
new file mode 100644
index 000000000..85578d4be
--- /dev/null
+++ b/kernel/include/linux/spi/spi_bitbang.h
@@ -0,0 +1,47 @@
+#ifndef __SPI_BITBANG_H
+#define __SPI_BITBANG_H
+
+#include <linux/workqueue.h>
+
+struct spi_bitbang {
+ spinlock_t lock;
+ u8 busy;
+ u8 use_dma;
+ u8 flags; /* extra spi->mode support */
+
+ 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
+
+ /* txrx_bufs() may handle dma mapping for transfers that don't
+ * already have one (transfer.{tx,rx}_dma is zero), or use PIO
+ */
+ int (*txrx_bufs)(struct spi_device *spi, struct spi_transfer *t);
+
+ /* txrx_word[SPI_MODE_*]() just looks like a shift register */
+ u32 (*txrx_word[4])(struct spi_device *spi,
+ unsigned nsecs,
+ u32 word, u8 bits);
+};
+
+/* you can call these default bitbang->master methods from your custom
+ * methods, if you like.
+ */
+extern int spi_bitbang_setup(struct spi_device *spi);
+extern void spi_bitbang_cleanup(struct spi_device *spi);
+extern int spi_bitbang_setup_transfer(struct spi_device *spi,
+ struct spi_transfer *t);
+
+/* start or stop queue processing */
+extern int spi_bitbang_start(struct spi_bitbang *spi);
+extern void spi_bitbang_stop(struct spi_bitbang *spi);
+
+#endif /* __SPI_BITBANG_H */