spi/bitbang: Factor out message transfer from message pump loop

In order to make it easier to convert to transfer_one_message() lift the
code that does the actual message transfer out of the work function that
implements the message pump. This should have no functional impact, it's
just a simple code motion patch.
Signed-off-by: Mark Brown <broonie@linaro.org>

drivers/spi/spi-bitbang.c

@@ -255,17 +255,10 @@ static int spi_bitbang_bufs(struct spi_device *spi, struct spi_transfer *t)
  * Drivers can provide word-at-a-time i/o primitives, or provide
  * transfer-at-a-time ones to leverage dma or fifo hardware.
  */
-static void bitbang_work(struct work_struct *work)
+static int spi_bitbang_transfer_one(struct spi_device *spi,
+				    struct spi_message *m)
 {
-	struct spi_bitbang	*bitbang =
-		container_of(work, struct spi_bitbang, work);
-	unsigned long		flags;
-	struct spi_message	*m, *_m;
-
-	spin_lock_irqsave(&bitbang->lock, flags);
-	bitbang->busy = 1;
-	list_for_each_entry_safe(m, _m, &bitbang->queue, queue) {
-		struct spi_device	*spi;
+	struct spi_bitbang 	*bitbang;
 	unsigned		nsecs;
 	struct spi_transfer	*t = NULL;
 	unsigned		tmp;
@@ -273,8 +266,7 @@ static void bitbang_work(struct work_struct *work)
 	int			status;
 	int			do_setup = -1;
 
-		list_del(&m->queue);
-		spin_unlock_irqrestore(&bitbang->lock, flags);
+	bitbang = spi_master_get_devdata(spi->master);
 
 	/* FIXME this is made-up ... the correct value is known to
 	 * word-at-a-time bitbang code, and presumably chipselect()
@@ -282,7 +274,6 @@ static void bitbang_work(struct work_struct *work)
 	 */
 	nsecs = 100;
 
-		spi = m->spi;
 	tmp = 0;
 	cs_change = 1;
 	status = 0;
@@ -367,6 +358,24 @@ static void bitbang_work(struct work_struct *work)
 		ndelay(nsecs);
 	}
 
+	return status;
+}
+
+static void bitbang_work(struct work_struct *work)
+{
+	struct spi_bitbang	*bitbang =
+		container_of(work, struct spi_bitbang, work);
+	unsigned long		flags;
+	struct spi_message	*m, *_m;
+
+	spin_lock_irqsave(&bitbang->lock, flags);
+	bitbang->busy = 1;
+	list_for_each_entry_safe(m, _m, &bitbang->queue, queue) {
+		list_del(&m->queue);
+		spin_unlock_irqrestore(&bitbang->lock, flags);
+
+		spi_bitbang_transfer_one(m->spi, m);
+
 		spin_lock_irqsave(&bitbang->lock, flags);
 	}
 	bitbang->busy = 0;