spi/omap: Add DT support to McSPI driver

Add device tree support to the OMAP2+ McSPI driver.
Add the bindings documentation.

Based on original code from Rajendra.

Signed-off-by: Benoit Cousson <b-cousson@ti.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 48 insertions, 8 deletions

diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c
index 0b0dfb71c640..bb9274c2526d 100644
--- a/drivers/spi/spi-omap2-mcspi.c
+++ b/drivers/spi/spi-omap2-mcspi.c
@@ -34,6 +34,8 @@
 #include <linux/io.h>
 #include <linux/slab.h>
 #include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
 
 #include <linux/spi/spi.h>
 
@@ -1079,15 +1081,39 @@ static int omap_mcspi_runtime_resume(struct device *dev)
         return 0;
 }
 
+static struct omap2_mcspi_platform_config omap2_pdata = {
+        .regs_offset = 0,
+};
+
+static struct omap2_mcspi_platform_config omap4_pdata = {
+        .regs_offset = OMAP4_MCSPI_REG_OFFSET,
+};
+
+static const struct of_device_id omap_mcspi_of_match[] = {
+        {
+                .compatible = "ti,omap2-mcspi",
+                .data = &omap2_pdata,
+        },
+        {
+                .compatible = "ti,omap4-mcspi",
+                .data = &omap4_pdata,
+        },
+        { },
+};
+MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
 
 static int __init omap2_mcspi_probe(struct platform_device *pdev)
 {
         struct spi_master       *master;
-        struct omap2_mcspi_platform_config *pdata = pdev->dev.platform_data;
+        struct omap2_mcspi_platform_config *pdata;
         struct omap2_mcspi      *mcspi;
         struct resource         *r;
         int                     status = 0, i;
         char                    wq_name[20];
+        u32                     regs_offset = 0;
+        static int              bus_num = 1;
+        struct device_node      *node = pdev->dev.of_node;
+        const struct of_device_id *match;
 
         master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
         if (master == NULL) {
@@ -1098,13 +1124,26 @@ static int __init omap2_mcspi_probe(struct platform_device *pdev)
         /* the spi->mode bits understood by this driver: */
         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
 
-        if (pdev->id != -1)
-                master->bus_num = pdev->id;
-
         master->setup = omap2_mcspi_setup;
         master->transfer = omap2_mcspi_transfer;
         master->cleanup = omap2_mcspi_cleanup;
-        master->num_chipselect = pdata->num_cs;
+        master->dev.of_node = node;
+
+        match = of_match_device(omap_mcspi_of_match, &pdev->dev);
+        if (match) {
+                u32 num_cs = 1; /* default number of chipselect */
+                pdata = match->data;
+
+                of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
+                master->num_chipselect = num_cs;
+                master->bus_num = bus_num++;
+        } else {
+                pdata = pdev->dev.platform_data;
+                master->num_chipselect = pdata->num_cs;
+                if (pdev->id != -1)
+                        master->bus_num = pdev->id;
+        }
+        regs_offset = pdata->regs_offset;
 
         dev_set_drvdata(&pdev->dev, master);
 
@@ -1124,8 +1163,8 @@ static int __init omap2_mcspi_probe(struct platform_device *pdev)
                 goto free_master;
         }
 
-        r->start += pdata->regs_offset;
-        r->end += pdata->regs_offset;
+        r->start += regs_offset;
+        r->end += regs_offset;
         mcspi->phys = r->start;
         if (!request_mem_region(r->start, resource_size(r),
                                 dev_name(&pdev->dev))) {
@@ -1285,7 +1324,8 @@ static struct platform_driver omap2_mcspi_driver = {
         .driver = {
                 .name =         "omap2_mcspi",
                 .owner =        THIS_MODULE,
-                .pm =           &omap2_mcspi_pm_ops
+                .pm =           &omap2_mcspi_pm_ops,
+                .of_match_table = omap_mcspi_of_match,
         },
         .remove =       __exit_p(omap2_mcspi_remove),
 };