1 files changed, 84 insertions, 1 deletions

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 70845ccd85c3..b76f2468a84a 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -23,6 +23,7 @@
 #include <linux/init.h>
 #include <linux/cache.h>
 #include <linux/mutex.h>
+#include <linux/mod_devicetable.h>
 #include <linux/spi/spi.h>
 
 
@@ -59,9 +60,32 @@ static struct device_attribute spi_dev_attrs[] = {
  * and the sysfs version makes coldplug work too.
  */
 
+static const struct spi_device_id *spi_match_id(const struct spi_device_id *id,
+						const struct spi_device *sdev)
+{
+	while (id->name[0]) {
+		if (!strcmp(sdev->modalias, id->name))
+			return id;
+		id++;
+	}
+	return NULL;
+}
+
+const struct spi_device_id *spi_get_device_id(const struct spi_device *sdev)
+{
+	const struct spi_driver *sdrv = to_spi_driver(sdev->dev.driver);
+
+	return spi_match_id(sdrv->id_table, sdev);
+}
+EXPORT_SYMBOL_GPL(spi_get_device_id);
+
 static int spi_match_device(struct device *dev, struct device_driver *drv)
 {
 	const struct spi_device	*spi = to_spi_device(dev);
+	const struct spi_driver	*sdrv = to_spi_driver(drv);
+
+	if (sdrv->id_table)
+		return !!spi_match_id(sdrv->id_table, spi);
 
 	return strcmp(spi->modalias, drv->name) == 0;
 }
@@ -70,7 +94,7 @@ static int spi_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
 	const struct spi_device		*spi = to_spi_device(dev);
 
-	add_uevent_var(env, "MODALIAS=%s", spi->modalias);
+	add_uevent_var(env, "MODALIAS=%s%s", SPI_MODULE_PREFIX, spi->modalias);
 	return 0;
 }
 
@@ -639,6 +663,65 @@ int spi_setup(struct spi_device *spi)
 }
 EXPORT_SYMBOL_GPL(spi_setup);
 
+/**
+ * spi_async - asynchronous SPI transfer
+ * @spi: device with which data will be exchanged
+ * @message: describes the data transfers, including completion callback
+ * Context: any (irqs may be blocked, etc)
+ *
+ * This call may be used in_irq and other contexts which can't sleep,
+ * as well as from task contexts which can sleep.
+ *
+ * The completion callback is invoked in a context which can't sleep.
+ * Before that invocation, the value of message->status is undefined.
+ * When the callback is issued, message->status holds either zero (to
+ * indicate complete success) or a negative error code.  After that
+ * callback returns, the driver which issued the transfer request may
+ * deallocate the associated memory; it's no longer in use by any SPI
+ * core or controller driver code.
+ *
+ * Note that although all messages to a spi_device are handled in
+ * FIFO order, messages may go to different devices in other orders.
+ * Some device might be higher priority, or have various "hard" access
+ * time requirements, for example.
+ *
+ * On detection of any fault during the transfer, processing of
+ * the entire message is aborted, and the device is deselected.
+ * Until returning from the associated message completion callback,
+ * no other spi_message queued to that device will be processed.
+ * (This rule applies equally to all the synchronous transfer calls,
+ * which are wrappers around this core asynchronous primitive.)
+ */
+int spi_async(struct spi_device *spi, struct spi_message *message)
+{
+	struct spi_master *master = spi->master;
+
+	/* Half-duplex links include original MicroWire, and ones with
+	 * only one data pin like SPI_3WIRE (switches direction) or where
+	 * either MOSI or MISO is missing.  They can also be caused by
+	 * software limitations.
+	 */
+	if ((master->flags & SPI_MASTER_HALF_DUPLEX)
+			|| (spi->mode & SPI_3WIRE)) {
+		struct spi_transfer *xfer;
+		unsigned flags = master->flags;
+
+		list_for_each_entry(xfer, &message->transfers, transfer_list) {
+			if (xfer->rx_buf && xfer->tx_buf)
+				return -EINVAL;
+			if ((flags & SPI_MASTER_NO_TX) && xfer->tx_buf)
+				return -EINVAL;
+			if ((flags & SPI_MASTER_NO_RX) && xfer->rx_buf)
+				return -EINVAL;
+		}
+	}
+
+	message->spi = spi;
+	message->status = -EINPROGRESS;
+	return master->transfer(spi, message);
+}
+EXPORT_SYMBOL_GPL(spi_async);
+
 
 /*-------------------------------------------------------------------------*/