spi/pl022: Add chip select handling via GPIO

This patch adds the ability for the driver to control the chip select directly.
This enables independence from cs_control callbacks.  Configurable via
platform_data, to be extended as DT in the following patch.

Based on the initial patch by Alexandre Pereira da Silva <aletes.xgr@gmail.com>

Signed-off-by: Roland Stigge <stigge@antcom.de>
Acked-by: Alexandre Pereira da Silva <aletes.xgr@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/include/linux/amba/pl022.h b/include/linux/amba/pl022.h
index fe1d7b2..854b729 100644
--- a/include/linux/amba/pl022.h
+++ b/include/linux/amba/pl022.h
@@ -244,6 +244,7 @@
  *     indicates no delay and the device will be suspended immediately.
  * @rt: indicates the controller should run the message pump with realtime
  *     priority to minimise the transfer latency on the bus.
+ * @chipselects: list of <num_chipselects> chip select gpios
  */
 struct pl022_ssp_controller {
 	u16 bus_id;
@@ -254,6 +255,7 @@
 	void *dma_tx_param;
 	int autosuspend_delay;
 	bool rt;
+	int *chipselects;
 };
 
 /**