1 files changed, 16 insertions, 0 deletions

diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 97b60b37f445..92e52a1e6af3 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -21,6 +21,7 @@
 
 #include <linux/device.h>
 #include <linux/mod_devicetable.h>
+#include <linux/slab.h>
 
 /*
  * INTERFACES between SPI master-side drivers and SPI infrastructure.
@@ -212,6 +213,9 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
  * @dma_alignment: SPI controller constraint on DMA buffers alignment.
  * @mode_bits: flags understood by this controller driver
  * @flags: other constraints relevant to this driver
+ * @bus_lock_spinlock: spinlock for SPI bus locking
+ * @bus_lock_mutex: mutex for SPI bus locking
+ * @bus_lock_flag: indicates that the SPI bus is locked for exclusive use
  * @setup: updates the device mode and clocking records used by a
  *      device's SPI controller; protocol code may call this.  This
  *      must fail if an unrecognized or unsupported mode is requested.
@@ -261,6 +265,13 @@ struct spi_master {
 #define SPI_MASTER_NO_RX        BIT(1)          /* can't do buffer read */
 #define SPI_MASTER_NO_TX        BIT(2)          /* can't do buffer write */
 
+        /* lock and mutex for SPI bus locking */
+        spinlock_t              bus_lock_spinlock;
+        struct mutex            bus_lock_mutex;
+
+        /* flag indicating that the SPI bus is locked for exclusive use */
+        bool                    bus_lock_flag;
+
         /* Setup mode and clock, etc (spi driver may call many times).
          *
          * IMPORTANT:  this may be called when transfers to another
@@ -541,6 +552,8 @@ static inline void spi_message_free(struct spi_message *m)
 
 extern int spi_setup(struct spi_device *spi);
 extern int spi_async(struct spi_device *spi, struct spi_message *message);
+extern int spi_async_locked(struct spi_device *spi,
+                            struct spi_message *message);
 
 /*---------------------------------------------------------------------------*/
 
@@ -550,6 +563,9 @@ extern int spi_async(struct spi_device *spi, struct spi_message *message);
  */
 
 extern int spi_sync(struct spi_device *spi, struct spi_message *message);
+extern int spi_sync_locked(struct spi_device *spi, struct spi_message *message);
+extern int spi_bus_lock(struct spi_master *master);
+extern int spi_bus_unlock(struct spi_master *master);
 
 /**
  * spi_write - SPI synchronous write