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>

diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
index 925cdbe08c2ee655d25eb790d86b50cd68c2d260..495e8869b9b046e24129847cfc33e573d5afe107 100644 (file)
--- 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,
        },
 };