drivers: mtd: rawnand: Add u-boot driver model support for ELM

To support u-boot driver model. Retain support legacy way of
doing things if ELM_BASE is defined in <asm/arch/hardware.h>

We could completely get rid of that if all platforms defining
ELM_BASE get rid of that definition. enable CONFIG_SYS_NAND_SELF_INIT

commit 7363cf0581a3 ("mtd: rawnand: omap_elm: u-boot driver model
support") upstream

Signed-off-by: Nitin Yadav <n-yadav@ti.com>

3 files changed, 53 insertions, 2 deletions

diff --git a/drivers/mtd/nand/raw/omap_elm.c b/drivers/mtd/nand/raw/omap_elm.c
index 35c6dd1f1b..35a066df41 100644
--- a/drivers/mtd/nand/raw/omap_elm.c
+++ b/drivers/mtd/nand/raw/omap_elm.c
@@ -15,9 +15,14 @@
 #include <common.h>
 #include <asm/io.h>
 #include <linux/errno.h>
-#include <linux/mtd/omap_elm.h>
 #include <asm/arch/hardware.h>
 
+#include <dm.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+
+#include "omap_elm.h"
+
 #define DRIVER_NAME		"omap-elm"
 #define ELM_DEFAULT_POLY (0)
 
@@ -180,6 +185,7 @@ void elm_reset(void)
 		;
 }
 
+#ifdef ELM_BASE
 /**
  * elm_init - Initialize ELM module
  *
@@ -191,3 +197,32 @@ void elm_init(void)
 	elm_cfg = (struct elm *)ELM_BASE;
 	elm_reset();
 }
+#endif
+
+#ifdef CONFIG_SYS_NAND_SELF_INIT
+static int elm_probe(struct udevice *dev)
+{
+#ifndef ELM_BASE
+	struct resource res;
+
+	dev_read_resource(dev, 0, &res);
+	elm_cfg = devm_ioremap(dev, res.start, resource_size(&res));
+	elm_reset();
+#endif
+
+	return 0;
+}
+
+static const struct udevice_id elm_ids[] = {
+	{ .compatible = "ti,am3352-elm" },
+	{ .compatible = "ti,am64-elm" },
+	{ }
+};
+
+U_BOOT_DRIVER(gpmc_elm) = {
+	.name           = DRIVER_NAME,
+	.id             = UCLASS_MTD,
+	.of_match       = elm_ids,
+	.probe          = elm_probe,
+};
+#endif /* CONFIG_SYS_NAND_SELF_INIT */
diff --git a/include/linux/mtd/omap_elm.h b/drivers/mtd/nand/raw/omap_elm.h
index f3db00d55d..a7f7bacb15 100644
--- a/include/linux/mtd/omap_elm.h
+++ b/drivers/mtd/nand/raw/omap_elm.h
@@ -74,6 +74,12 @@ int elm_check_error(u8 *syndrome, enum bch_level bch_type, u32 *error_count,
 		u32 *error_locations);
 int elm_config(enum bch_level level);
 void elm_reset(void);
+#ifdef ELM_BASE
 void elm_init(void);
+#else
+static inline void elm_init(void)
+{
+}
+#endif
 #endif /* __ASSEMBLY__ */
 #endif /* __ASM_ARCH_ELM_H */
diff --git a/drivers/mtd/nand/raw/omap_gpmc.c b/drivers/mtd/nand/raw/omap_gpmc.c
index f499d8611f..8c0f3a4233 100644
--- a/drivers/mtd/nand/raw/omap_gpmc.c
+++ b/drivers/mtd/nand/raw/omap_gpmc.c
@@ -13,10 +13,11 @@
 #include <linux/bch.h>
 #include <linux/compiler.h>
 #include <nand.h>
-#include <linux/mtd/omap_elm.h>
 #include <soc.h>
 #include <dm/uclass.h>
 
+#include "omap_elm.h"
+
 #define BADBLOCK_MARKER_LENGTH	2
 #define SECTOR_BYTES		512
 #define ECCSIZE0_SHIFT		12
@@ -1267,6 +1268,15 @@ void board_nand_init(void)
 	struct udevice *dev;
 	int ret;
 
+#ifdef CONFIG_NAND_OMAP_ELM
+	ret = uclass_get_device_by_driver(UCLASS_MTD,
+					  DM_GET_DRIVER(gpmc_elm), &dev);
+	if (ret && ret != -ENODEV) {
+		pr_err("%s: Failed to get ELM device: %d\n", __func__, ret);
+		return;
+	}
+#endif
+
 	ret = uclass_get_device_by_driver(UCLASS_MTD,
 					  DM_GET_DRIVER(gpmc_nand), &dev);
 	if (ret && ret != -ENODEV)