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authorDaniel Vetter <daniel.vetter@ffwll.ch>2013-03-19 09:47:30 +0100
committerDaniel Vetter <daniel.vetter@ffwll.ch>2013-03-19 09:47:30 +0100
commit0d4a42f6bd298e826620585e766a154ab460617a (patch)
tree406d8f7778691d858dbe3e48e4bbb10e99c0a58a /include/linux/spi/spi.h
parentd62b4892f3d9f7dd2002e5309be10719d6805b0f (diff)
parenta937536b868b8369b98967929045f1df54234323 (diff)
Merge tag 'v3.9-rc3' into drm-intel-next-queued
Backmerge so that I can merge Imre Deak's coalesced sg entries fixes, which depend upon the new for_each_sg_page introduce in commit a321e91b6d73ed011ffceed384c40d2785cf723b Author: Imre Deak <imre.deak@intel.com> Date: Wed Feb 27 17:02:56 2013 -0800 lib/scatterlist: add simple page iterator The merge itself is just two trivial conflicts: Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'include/linux/spi/spi.h')
-rw-r--r--include/linux/spi/spi.h49
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,