mtd: add device-tree support to spear_smi

This patch adds support to configure the SPEAr SMI driver 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>

3 files changed, 135 insertions, 12 deletions

diff --git a/Documentation/devicetree/bindings/mtd/spear_smi.txt b/Documentation/devicetree/bindings/mtd/spear_smi.txt
new file mode 100644
index 000000000000..7248aadd89e4
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/spear_smi.txt
@@ -0,0 +1,31 @@
+* SPEAr SMI
+
+Required properties:
+- compatible : "st,spear600-smi"
+- reg : Address range of the mtd chip
+- #address-cells, #size-cells : Must be present if the device has sub-nodes
+  representing partitions.
+- interrupt-parent: Should be the phandle for the interrupt controller
+  that services interrupts for this device
+- interrupts: Should contain the STMMAC interrupts
+- clock-rate : Functional clock rate of SMI in Hz
+
+Optional properties:
+- st,smi-fast-mode : Flash supports read in fast mode
+
+Example:
+
+        smi: flash@fc000000 {
+                compatible = "st,spear600-smi";
+                #address-cells = <1>;
+                #size-cells = <1>;
+                reg = <0xfc000000 0x1000>;
+                interrupt-parent = <&vic1>;
+                interrupts = <12>;
+                clock-rate = <50000000>;        /* 50MHz */
+
+                flash@f8000000 {
+                        st,smi-fast-mode;
+                        ...
+                };
+        };
diff --git a/drivers/mtd/devices/spear_smi.c b/drivers/mtd/devices/spear_smi.c
index f7f34fd1a3e5..797d43cd3550 100644
--- a/drivers/mtd/devices/spear_smi.c
+++ b/drivers/mtd/devices/spear_smi.c
@@ -33,9 +33,8 @@
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/wait.h>
-
-/* max possible slots for serial-nor flash chip in the SMI controller */
-#define MAX_NUM_FLASH_CHIP      4
+#include <linux/of.h>
+#include <linux/of_address.h>
 
 /* SMI clock rate */
 #define SMI_MAX_CLOCK_FREQ      50000000 /* 50 MHz */
@@ -748,9 +747,63 @@ err_probe:
         return ret;
 }
 
-static int spear_smi_setup_banks(struct platform_device *pdev, u32 bank)
+
+#ifdef CONFIG_OF
+static int __devinit spear_smi_probe_config_dt(struct platform_device *pdev,
+                                               struct device_node *np)
+{
+        struct spear_smi_plat_data *pdata = dev_get_platdata(&pdev->dev);
+        struct device_node *pp = NULL;
+        const __be32 *addr;
+        u32 val;
+        int len;
+        int i = 0;
+
+        if (!np)
+                return -ENODEV;
+
+        of_property_read_u32(np, "clock-rate", &val);
+        pdata->clk_rate = val;
+
+        pdata->board_flash_info = devm_kzalloc(&pdev->dev,
+                                               sizeof(*pdata->board_flash_info),
+                                               GFP_KERNEL);
+
+        /* Fill structs for each subnode (flash device) */
+        while ((pp = of_get_next_child(np, pp))) {
+                struct spear_smi_flash_info *flash_info;
+
+                flash_info = &pdata->board_flash_info[i];
+                pdata->np[i] = pp;
+
+                /* Read base-addr and size from DT */
+                addr = of_get_property(pp, "reg", &len);
+                pdata->board_flash_info->mem_base = be32_to_cpup(&addr[0]);
+                pdata->board_flash_info->size = be32_to_cpup(&addr[1]);
+
+                if (of_get_property(pp, "st,smi-fast-mode", NULL))
+                        pdata->board_flash_info->fast_mode = 1;
+
+                i++;
+        }
+
+        pdata->num_flashes = i;
+
+        return 0;
+}
+#else
+static int __devinit spear_smi_probe_config_dt(struct platform_device *pdev,
+                                               struct device_node *np)
+{
+        return -ENOSYS;
+}
+#endif
+
+static int spear_smi_setup_banks(struct platform_device *pdev,
+                                 u32 bank, struct device_node *np)
 {
         struct spear_smi *dev = platform_get_drvdata(pdev);
+        struct mtd_part_parser_data ppdata = {};
         struct spear_smi_flash_info *flash_info;
         struct spear_smi_plat_data *pdata;
         struct spear_snor_flash *flash;
@@ -816,11 +869,16 @@ static int spear_smi_setup_banks(struct platform_device *pdev, u32 bank)
         dev_info(&dev->pdev->dev, ".erasesize = 0x%x(%uK)\n",
                         flash->mtd.erasesize, flash->mtd.erasesize / 1024);
 
+#ifndef CONFIG_OF
         if (flash_info->partitions) {
                 parts = flash_info->partitions;
                 count = flash_info->nr_partitions;
         }
-        ret = mtd_device_parse_register(&flash->mtd, NULL, NULL, parts, count);
+#endif
+        ppdata.of_node = np;
+
+        ret = mtd_device_parse_register(&flash->mtd, NULL, &ppdata, parts,
+                                        count);
         if (ret) {
                 dev_err(&dev->pdev->dev, "Err MTD partition=%d\n", ret);
                 goto err_map;
@@ -847,17 +905,34 @@ err_probe:
  */
 static int __devinit spear_smi_probe(struct platform_device *pdev)
 {
-        struct spear_smi_plat_data *pdata;
+        struct device_node *np = pdev->dev.of_node;
+        struct spear_smi_plat_data *pdata = NULL;
         struct spear_smi *dev;
         struct resource *smi_base;
         int irq, ret = 0;
         int i;
 
-        pdata = dev_get_platdata(&pdev->dev);
-        if (pdata < 0) {
-                ret = -ENODEV;
-                dev_err(&pdev->dev, "no platform data\n");
-                goto err;
+        if (np) {
+                pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+                if (!pdata) {
+                        pr_err("%s: ERROR: no memory", __func__);
+                        ret = -ENOMEM;
+                        goto err;
+                }
+                pdev->dev.platform_data = pdata;
+                ret = spear_smi_probe_config_dt(pdev, np);
+                if (ret) {
+                        ret = -ENODEV;
+                        dev_err(&pdev->dev, "no platform data\n");
+                        goto err;
+                }
+        } else {
+                pdata = dev_get_platdata(&pdev->dev);
+                if (pdata < 0) {
+                        ret = -ENODEV;
+                        dev_err(&pdev->dev, "no platform data\n");
+                        goto err;
+                }
         }
 
         smi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -932,7 +1007,7 @@ static int __devinit spear_smi_probe(struct platform_device *pdev)
 
         /* loop for each serial nor-flash which is connected to smi */
         for (i = 0; i < dev->num_flashes; i++) {
-                ret = spear_smi_setup_banks(pdev, i);
+                ret = spear_smi_setup_banks(pdev, i, pdata->np[i]);
                 if (ret) {
                         dev_err(&dev->pdev->dev, "bank setup failed\n");
                         goto err_bank_setup;
@@ -967,6 +1042,7 @@ err:
 static int __devexit spear_smi_remove(struct platform_device *pdev)
 {
         struct spear_smi *dev;
+        struct spear_smi_plat_data *pdata;
         struct spear_snor_flash *flash;
         struct resource *smi_base;
         int ret;
@@ -978,6 +1054,8 @@ static int __devexit spear_smi_remove(struct platform_device *pdev)
                 return -ENODEV;
         }
 
+        pdata = dev_get_platdata(&pdev->dev);
+
         /* clean up for all nor flash */
         for (i = 0; i < dev->num_flashes; i++) {
                 flash = dev->flash[i];
@@ -1031,11 +1109,20 @@ int spear_smi_resume(struct platform_device *pdev)
         return ret;
 }
 
+#ifdef CONFIG_OF
+static const struct of_device_id spear_smi_id_table[] = {
+        { .compatible = "st,spear600-smi" },
+        {}
+};
+MODULE_DEVICE_TABLE(of, spear_smi_id_table);
+#endif
+
 static struct platform_driver spear_smi_driver = {
         .driver = {
                 .name = "smi",
                 .bus = &platform_bus_type,
                 .owner = THIS_MODULE,
+                .of_match_table = of_match_ptr(spear_smi_id_table),
         },
         .probe = spear_smi_probe,
         .remove = __devexit_p(spear_smi_remove),
diff --git a/include/linux/mtd/spear_smi.h b/include/linux/mtd/spear_smi.h
index 4e26b4e38da3..8ae1726044c3 100644
--- a/include/linux/mtd/spear_smi.h
+++ b/include/linux/mtd/spear_smi.h
@@ -14,6 +14,10 @@
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/partitions.h>
 #include <linux/platform_device.h>
+#include <linux/of.h>
+
+/* max possible slots for serial-nor flash chip in the SMI controller */
+#define MAX_NUM_FLASH_CHIP      4
 
 /* macro to define partitions for flash devices */
 #define DEFINE_PARTS(n, of, s)          \
@@ -55,6 +59,7 @@ struct spear_smi_plat_data {
         unsigned long clk_rate;
         int num_flashes;
         struct spear_smi_flash_info *board_flash_info;
+        struct device_node *np[MAX_NUM_FLASH_CHIP];
 };
 
 #endif /* __MTD_SPEAR_SMI_H */