MTD: pxa3xx-nand: add devicetree bindings

This patch contains a hack to get the DMA resources of the device when
probed from a devicetree node. This can be removed once a generic DMA
controller framework lands.

A mtd_part_parser_data is passed mtd_device_parse_register which
contains a reference to the device node, so MTD partitions can be
added as children.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>

2 files changed, 102 insertions, 14 deletions

diff --git a/Documentation/devicetree/bindings/mtd/pxa3xx-nand.txt b/Documentation/devicetree/bindings/mtd/pxa3xx-nand.txt
new file mode 100644
index 000000000000..f1421e2bbab7
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/pxa3xx-nand.txt
@@ -0,0 +1,31 @@
+PXA3xx NAND DT bindings
+
+Required properties:
+
+ - compatible:          Should be "marvell,pxa3xx-nand"
+ - reg:                 The register base for the controller
+ - interrupts:          The interrupt to map
+ - #address-cells:      Set to <1> if the node includes partitions
+
+Optional properties:
+
+ - marvell,nand-enable-arbiter: Set to enable the bus arbiter
+ - marvell,nand-keep-config:    Set to keep the NAND controller config as set
+                                by the bootloader
+ - num-cs:                      Number of chipselect lines to usw
+
+Example:
+
+        nand0: nand@43100000 {
+                compatible = "marvell,pxa3xx-nand";
+                reg = <0x43100000 90>;
+                interrupts = <45>;
+                #address-cells = <1>;
+
+                marvell,nand-enable-arbiter;
+                marvell,nand-keep-config;
+                num-cs = <1>;
+
+                /* partitions (optional) */
+        };
+
diff --git a/drivers/mtd/nand/pxa3xx_nand.c b/drivers/mtd/nand/pxa3xx_nand.c
index 252aaefcacfa..b0319d8934ad 100644
--- a/drivers/mtd/nand/pxa3xx_nand.c
+++ b/drivers/mtd/nand/pxa3xx_nand.c
@@ -22,6 +22,8 @@
 #include <linux/io.h>
 #include <linux/irq.h>
 #include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
 
 #include <mach/dma.h>
 #include <plat/pxa3xx_nand.h>
@@ -1081,21 +1083,31 @@ static int alloc_nand_resource(struct platform_device *pdev)
         }
         clk_enable(info->clk);
 
-        r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
-        if (r == NULL) {
-                dev_err(&pdev->dev, "no resource defined for data DMA\n");
-                ret = -ENXIO;
-                goto fail_put_clk;
-        }
-        info->drcmr_dat = r->start;
+        /*
+         * This is a dirty hack to make this driver work from devicetree
+         * bindings. It can be removed once we have a prober DMA controller
+         * framework for DT.
+         */
+        if (pdev->dev.of_node && cpu_is_pxa3xx()) {
+                info->drcmr_dat = 97;
+                info->drcmr_cmd = 99;
+        } else {
+                r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
+                if (r == NULL) {
+                        dev_err(&pdev->dev, "no resource defined for data DMA\n");
+                        ret = -ENXIO;
+                        goto fail_put_clk;
+                }
+                info->drcmr_dat = r->start;
 
-        r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
-        if (r == NULL) {
-                dev_err(&pdev->dev, "no resource defined for command DMA\n");
-                ret = -ENXIO;
-                goto fail_put_clk;
+                r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
+                if (r == NULL) {
+                        dev_err(&pdev->dev, "no resource defined for command DMA\n");
+                        ret = -ENXIO;
+                        goto fail_put_clk;
+                }
+                info->drcmr_cmd = r->start;
         }
-        info->drcmr_cmd = r->start;
 
         irq = platform_get_irq(pdev, 0);
         if (irq < 0) {
@@ -1200,12 +1212,55 @@ static int pxa3xx_nand_remove(struct platform_device *pdev)
         return 0;
 }
 
+#ifdef CONFIG_OF
+static struct of_device_id pxa3xx_nand_dt_ids[] = {
+        { .compatible = "marvell,pxa3xx-nand" },
+        {}
+};
+MODULE_DEVICE_TABLE(of, i2c_pxa_dt_ids);
+
+static int pxa3xx_nand_probe_dt(struct platform_device *pdev)
+{
+        struct pxa3xx_nand_platform_data *pdata;
+        struct device_node *np = pdev->dev.of_node;
+        const struct of_device_id *of_id =
+                        of_match_device(pxa3xx_nand_dt_ids, &pdev->dev);
+
+        if (!of_id)
+                return 0;
+
+        pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+        if (!pdata)
+                return -ENOMEM;
+
+        if (of_get_property(np, "marvell,nand-enable-arbiter", NULL))
+                pdata->enable_arbiter = 1;
+        if (of_get_property(np, "marvell,nand-keep-config", NULL))
+                pdata->keep_config = 1;
+        of_property_read_u32(np, "num-cs", &pdata->num_cs);
+
+        pdev->dev.platform_data = pdata;
+
+        return 0;
+}
+#else
+static inline int pxa3xx_nand_probe_dt(struct platform_device *)
+{
+        return 0;
+}
+#endif
+
 static int pxa3xx_nand_probe(struct platform_device *pdev)
 {
         struct pxa3xx_nand_platform_data *pdata;
+        struct mtd_part_parser_data ppdata = {};
         struct pxa3xx_nand_info *info;
         int ret, cs, probe_success;
 
+        ret = pxa3xx_nand_probe_dt(pdev);
+        if (ret)
+                return ret;
+
         pdata = pdev->dev.platform_data;
         if (!pdata) {
                 dev_err(&pdev->dev, "no platform data defined\n");
@@ -1229,8 +1284,9 @@ static int pxa3xx_nand_probe(struct platform_device *pdev)
                         continue;
                 }
 
+                ppdata.of_node = pdev->dev.of_node;
                 ret = mtd_device_parse_register(info->host[cs]->mtd, NULL,
-                                                NULL, pdata->parts[cs],
+                                                &ppdata, pdata->parts[cs],
                                                 pdata->nr_parts[cs]);
                 if (!ret)
                         probe_success = 1;
@@ -1306,6 +1362,7 @@ static int pxa3xx_nand_resume(struct platform_device *pdev)
 static struct platform_driver pxa3xx_nand_driver = {
         .driver = {
                 .name   = "pxa3xx-nand",
+                .of_match_table = of_match_ptr(pxa3xx_nand_dt_ids),
         },
         .probe          = pxa3xx_nand_probe,
         .remove         = pxa3xx_nand_remove,