1 files changed, 49 insertions, 0 deletions

diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index f62918946d86..38c2b925923d 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -57,6 +57,8 @@ extern struct bus_type spi_bus_type;
  * @modalias: Name of the driver to use with this device, or an alias
  *      for that name.  This appears in the sysfs "modalias" attribute
  *      for driver coldplugging, and in uevents used for hotplugging
+ * @cs_gpio: gpio number of the chipselect line (optional, -EINVAL when
+ *      when not using a GPIO line)
  *
  * A @spi_device is used to interchange data between an SPI slave
  * (usually a discrete chip) and CPU memory.
@@ -258,6 +260,9 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
  * @unprepare_transfer_hardware: there are currently no more messages on the
  *      queue so the subsystem notifies the driver that it may relax the
  *      hardware by issuing this call
+ * @cs_gpios: Array of GPIOs to use as chip select lines; one per CS
+ *      number. Any individual value may be -EINVAL for CS lines that
+ *      are not GPIOs (driven by the SPI controller itself).
  *
  * Each SPI master controller can communicate with one or more @spi_device
  * children.  These make a small bus, sharing MOSI, MISO and SCK signals
@@ -591,6 +596,26 @@ spi_transfer_del(struct spi_transfer *t)
         list_del(&t->transfer_list);
 }
 
+/**
+ * spi_message_init_with_transfers - Initialize spi_message and append transfers
+ * @m: spi_message to be initialized
+ * @xfers: An array of spi transfers
+ * @num_xfers: Number of items in the xfer array
+ *
+ * This function initializes the given spi_message and adds each spi_transfer in
+ * the given array to the message.
+ */
+static inline void
+spi_message_init_with_transfers(struct spi_message *m,
+struct spi_transfer *xfers, unsigned int num_xfers)
+{
+        unsigned int i;
+
+        spi_message_init(m);
+        for (i = 0; i < num_xfers; ++i)
+                spi_message_add_tail(&xfers[i], m);
+}
+
 /* It's fine to embed message and transaction structures in other data
  * structures so long as you don't free them while they're in use.
  */
@@ -683,6 +708,30 @@ spi_read(struct spi_device *spi, void *buf, size_t len)
         return spi_sync(spi, &m);
 }
 
+/**
+ * spi_sync_transfer - synchronous SPI data transfer
+ * @spi: device with which data will be exchanged
+ * @xfers: An array of spi_transfers
+ * @num_xfers: Number of items in the xfer array
+ * Context: can sleep
+ *
+ * Does a synchronous SPI data transfer of the given spi_transfer array.
+ *
+ * For more specific semantics see spi_sync().
+ *
+ * It returns zero on success, else a negative error code.
+ */
+static inline int
+spi_sync_transfer(struct spi_device *spi, struct spi_transfer *xfers,
+        unsigned int num_xfers)
+{
+        struct spi_message msg;
+
+        spi_message_init_with_transfers(&msg, xfers, num_xfers);
+
+        return spi_sync(spi, &msg);
+}
+
 /* this copies txbuf and rxbuf data; for small transfers only! */
 extern int spi_write_then_read(struct spi_device *spi,
                 const void *txbuf, unsigned n_tx,