spi: sirf: reset SPI controller in init stage

in SPI boot mode, romcode uses SPI controller to fetch data from NOR
flash. Here we need to reset the hardware IP to restore its state.
Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-sirf.c

@@ -23,6 +23,7 @@
 #include <linux/dmaengine.h>
 #include <linux/dma-direction.h>
 #include <linux/dma-mapping.h>
+#include <linux/reset.h>
 
 #define DRIVER_NAME "sirfsoc_spi"
 
@@ -647,6 +648,12 @@ static int spi_sirfsoc_probe(struct platform_device *pdev)
 	int irq;
 	int i, ret;
 
+	ret = device_reset(&pdev->dev);
+	if (ret) {
+		dev_err(&pdev->dev, "SPI reset failed!\n");
+		return ret;
+	}
+
 	master = spi_alloc_master(&pdev->dev, sizeof(*sspi));
 	if (!master) {
 		dev_err(&pdev->dev, "Unable to allocate SPI master\n");