dmaengine: ste_dma40: Allow driver to be probe()able when DT is enabled

When booting using Device Tree, devices aren't registered in the normal
way. Instead, they need to be provided with a compatible string which is
held in an OF Match Table for comparison during start-up. Here we provide
the compatible string and prepare the driver to not receive a platform
data pointer.

Acked-by: Vinod Koul <vnod.koul@intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
[Fixed up whitespace error]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 44 insertions, 2 deletions

diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
index 925cdbe08c2e..495e8869b9b0 100644
--- a/drivers/dma/ste_dma40.c
+++ b/drivers/dma/ste_dma40.c
@@ -17,6 +17,7 @@
 #include <linux/pm.h>
 #include <linux/pm_runtime.h>
 #include <linux/err.h>
+#include <linux/of.h>
 #include <linux/amba/bus.h>
 #include <linux/regulator/consumer.h>
 #include <linux/platform_data/dma-ste-dma40.h>
@@ -3471,17 +3472,52 @@ failure:
         return ret;
 }
 
+static int __init d40_of_probe(struct platform_device *pdev,
+                               struct device_node *np)
+{
+        struct stedma40_platform_data *pdata;
+
+        /*
+         * FIXME: Fill in this routine as more support is added.
+         * First platform enabled (u8500) doens't need any extra
+         * properties to run, so this is fairly sparce currently.
+         */
+
+        pdata = devm_kzalloc(&pdev->dev,
+                             sizeof(struct stedma40_platform_data),
+                             GFP_KERNEL);
+        if (!pdata)
+                return -ENOMEM;
+
+        pdev->dev.platform_data = pdata;
+
+        return 0;
+}
+
 static int __init d40_probe(struct platform_device *pdev)
 {
+        struct stedma40_platform_data *plat_data = pdev->dev.platform_data;
+        struct device_node *np = pdev->dev.of_node;
         int err;
         int ret = -ENOENT;
-        struct d40_base *base;
+        struct d40_base *base = NULL;
         struct resource *res = NULL;
         int num_reserved_chans;
         u32 val;
 
-        base = d40_hw_detect_init(pdev);
+        if (!plat_data) {
+                if (np) {
+                        if(d40_of_probe(pdev, np)) {
+                                ret = -ENOMEM;
+                                goto failure;
+                        }
+                } else {
+                        d40_err(&pdev->dev, "No pdata or Device Tree provided\n");
+                        goto failure;
+                }
+        }
 
+        base = d40_hw_detect_init(pdev);
         if (!base)
                 goto failure;
 
@@ -3655,11 +3691,17 @@ failure:
         return ret;
 }
 
+static const struct of_device_id d40_match[] = {
+        { .compatible = "stericsson,dma40", },
+        {}
+};
+
 static struct platform_driver d40_driver = {
         .driver = {
                 .owner = THIS_MODULE,
                 .name  = D40_NAME,
                 .pm = DMA40_PM_OPS,
+                .of_match_table = d40_match,
         },
 };