spi: dw-mmio: add devicetree support

Allow probing the dw-mmio from devicetree.

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Mark Brown <broonie@linaro.org>

1 files changed, 18 insertions, 1 deletions

diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c
index a5cba14ac3d2..21ce0e36fa00 100644
--- a/drivers/spi/spi-dw-mmio.c
+++ b/drivers/spi/spi-dw-mmio.c
@@ -16,7 +16,9 @@
 #include <linux/spi/spi.h>
 #include <linux/scatterlist.h>
 #include <linux/module.h>
+#include <linux/of.h>
 #include <linux/of_gpio.h>
+#include <linux/of_platform.h>
 
 #include "spi-dw.h"
 
@@ -33,6 +35,7 @@ static int dw_spi_mmio_probe(struct platform_device *pdev)
         struct dw_spi *dws;
         struct resource *mem;
         int ret;
+        int num_cs;
 
         dwsmmio = devm_kzalloc(&pdev->dev, sizeof(struct dw_spi_mmio),
                         GFP_KERNEL);
@@ -68,9 +71,16 @@ static int dw_spi_mmio_probe(struct platform_device *pdev)
                 return ret;
 
         dws->bus_num = pdev->id;
-        dws->num_cs = 4;
+
         dws->max_freq = clk_get_rate(dwsmmio->clk);
 
+        num_cs = 4;
+
+        if (pdev->dev.of_node)
+                of_property_read_u32(pdev->dev.of_node, "num-cs", &num_cs);
+
+        dws->num_cs = num_cs;
+
         if (pdev->dev.of_node) {
                 int i;
 
@@ -114,12 +124,19 @@ static int dw_spi_mmio_remove(struct platform_device *pdev)
         return 0;
 }
 
+static const struct of_device_id dw_spi_mmio_of_match[] = {
+        { .compatible = "snps,dw-apb-ssi", },
+        { /* end of table */}
+};
+MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match);
+
 static struct platform_driver dw_spi_mmio_driver = {
         .probe          = dw_spi_mmio_probe,
         .remove         = dw_spi_mmio_remove,
         .driver         = {
                 .name   = DRIVER_NAME,
                 .owner  = THIS_MODULE,
+                .of_match_table = dw_spi_mmio_of_match,
         },
 };
 module_platform_driver(dw_spi_mmio_driver);