mtd: Add device-tree support to fsmc_nand

This patch adds support to configure the FSMC NAND driver (used amongst
others on SPEAr platforms) via device-tree instead of platform_data.

Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

diff --git a/Documentation/devicetree/bindings/mtd/fsmc-nand.txt b/Documentation/devicetree/bindings/mtd/fsmc-nand.txt
new file mode 100644 (file)
index 0000000..e2c663b
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/fsmc-nand.txt
@@ -0,0 +1,33 @@
+* FSMC NAND
+
+Required properties:
+- compatible : "st,spear600-fsmc-nand"
+- reg : Address range of the mtd chip
+- reg-names: Should contain the reg names "fsmc_regs" and "nand_data"
+- st,ale-off : Chip specific offset to ALE
+- st,cle-off : Chip specific offset to CLE
+
+Optional properties:
+- bank-width : Width (in bytes) of the device.  If not present, the width
+  defaults to 1 byte
+- nand-skip-bbtscan: Indicates the the BBT scanning should be skipped
+
+Example:
+
+       fsmc: flash@d1800000 {
+               compatible = "st,spear600-fsmc-nand";
+               #address-cells = <1>;
+               #size-cells = <1>;
+               reg = <0xd1800000 0x1000        /* FSMC Register */
+                      0xd2000000 0x4000>;      /* NAND Base */
+               reg-names = "fsmc_regs", "nand_data";
+               st,ale-off = <0x20000>;
+               st,cle-off = <0x10000>;
+
+               bank-width = <1>;
+               nand-skip-bbtscan;
+
+               partition@0 {
+                       ...
+               };
+       };

diff --git a/drivers/mtd/nand/fsmc_nand.c b/drivers/mtd/nand/fsmc_nand.c
index 0490182..1b8330e 100644 (file)
--- a/drivers/mtd/nand/fsmc_nand.c
+++ b/drivers/mtd/nand/fsmc_nand.c
@@ -31,6 +31,7 @@
 #include <linux/mtd/nand.h>
 #include <linux/mtd/nand_ecc.h>
 #include <linux/platform_device.h>
+#include <linux/of.h>
 #include <linux/mtd/partitions.h>
 #include <linux/io.h>
 #include <linux/slab.h>
@@ -854,6 +855,38 @@ static bool filter(struct dma_chan *chan, void *slave)
        return true;
 }
 
+#ifdef CONFIG_OF
+static int __devinit fsmc_nand_probe_config_dt(struct platform_device *pdev,
+                                              struct device_node *np)
+{
+       struct fsmc_nand_platform_data *pdata = dev_get_platdata(&pdev->dev);
+       u32 val;
+
+       /* Set default NAND width to 8 bits */
+       pdata->width = 8;
+       if (!of_property_read_u32(np, "bank-width", &val)) {
+               if (val == 2) {
+                       pdata->width = 16;
+               } else if (val != 1) {
+                       dev_err(&pdev->dev, "invalid bank-width %u\n", val);
+                       return -EINVAL;
+               }
+       }
+       of_property_read_u32(np, "st,ale-off", &pdata->ale_off);
+       of_property_read_u32(np, "st,cle-off", &pdata->cle_off);
+       if (of_get_property(np, "nand-skip-bbtscan", NULL))
+               pdata->options = NAND_SKIP_BBTSCAN;
+
+       return 0;
+}
+#else
+static int __devinit fsmc_nand_probe_config_dt(struct platform_device *pdev,
+                                              struct device_node *np)
+{
+       return -ENOSYS;
+}
+#endif
+
 /*
  * fsmc_nand_probe - Probe function
  * @pdev:       platform device structure
@@ -861,6 +894,8 @@ static bool filter(struct dma_chan *chan, void *slave)
 static int __init fsmc_nand_probe(struct platform_device *pdev)
 {
        struct fsmc_nand_platform_data *pdata = dev_get_platdata(&pdev->dev);
+       struct device_node __maybe_unused *np = pdev->dev.of_node;
+       struct mtd_part_parser_data ppdata = {};
        struct fsmc_nand_data *host;
        struct mtd_info *mtd;
        struct nand_chip *nand;
@@ -870,6 +905,16 @@ static int __init fsmc_nand_probe(struct platform_device *pdev)
        u32 pid;
        int i;
 
+       if (np) {
+               pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+               pdev->dev.platform_data = pdata;
+               ret = fsmc_nand_probe_config_dt(pdev, np);
+               if (ret) {
+                       dev_err(&pdev->dev, "no platform data\n");
+                       return -ENODEV;
+               }
+       }
+
        if (!pdata) {
                dev_err(&pdev->dev, "platform data is NULL\n");
                return -EINVAL;
@@ -1113,7 +1158,8 @@ static int __init fsmc_nand_probe(struct platform_device *pdev)
         * Check for partition info passed
         */
        host->mtd.name = "nand";
-       ret = mtd_device_parse_register(&host->mtd, NULL, NULL,
+       ppdata.of_node = np;
+       ret = mtd_device_parse_register(&host->mtd, NULL, &ppdata,
                                        host->partitions, host->nr_partitions);
        if (ret)
                goto err_probe;
@@ -1183,11 +1229,20 @@ static int fsmc_nand_resume(struct device *dev)
 static SIMPLE_DEV_PM_OPS(fsmc_nand_pm_ops, fsmc_nand_suspend, fsmc_nand_resume);
 #endif
 
+#ifdef CONFIG_OF
+static const struct of_device_id fsmc_nand_id_table[] = {
+       { .compatible = "st,spear600-fsmc-nand" },
+       {}
+};
+MODULE_DEVICE_TABLE(of, fsmc_nand_id_table);
+#endif
+
 static struct platform_driver fsmc_nand_driver = {
        .remove = fsmc_nand_remove,
        .driver = {
                .owner = THIS_MODULE,
                .name = "fsmc-nand",
+               .of_match_table = of_match_ptr(fsmc_nand_id_table),
 #ifdef CONFIG_PM
                .pm = &fsmc_nand_pm_ops,
 #endif

diff --git a/include/linux/mtd/fsmc.h b/include/linux/mtd/fsmc.h
index 823359c..b200292 100644 (file)
--- a/include/linux/mtd/fsmc.h
+++ b/include/linux/mtd/fsmc.h
@@ -156,8 +156,8 @@ struct fsmc_nand_platform_data {
        unsigned int            bank;
 
        /* CLE, ALE offsets */
-       unsigned long           cle_off;
-       unsigned long           ale_off;
+       unsigned int            cle_off;
+       unsigned int            ale_off;
        enum access_mode        mode;
 
        void                    (*select_bank)(uint32_t bank, uint32_t busw);