From 71261ca81b491a4c3b08690347c12e96a75ad0d0 Mon Sep 17 00:00:00 2001
From: John Crispin <blogic@openwrt.org>
Date: Sun, 17 Mar 2013 00:55:04 +0100
Subject: [PATCH 3/5] wifi: rt2x00: Add support for loading EEPROM from MTD

Add support for loading EEPROM from MTD.

Signed-off-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
 drivers/net/wireless/ralink/rt2x00/Kconfig    |  1 +
 .../net/wireless/ralink/rt2x00/rt2x00eeprom.c | 66 +++++++++++++++++++
 2 files changed, 67 insertions(+)

--- a/drivers/net/wireless/ralink/rt2x00/Kconfig
+++ b/drivers/net/wireless/ralink/rt2x00/Kconfig
@@ -220,6 +220,7 @@ config RT2800SOC
 	select RT2X00_LIB_EEPROM
 	select RT2800_LIB
 	select RT2800_LIB_MMIO
+	select MTD if SOC_RT288X || SOC_RT305X
 	help
 	  This adds support for Ralink WiSoC devices.
 	  Supported chips: RT2880, RT3050, RT3052, RT3350, RT3352.
--- a/drivers/net/wireless/ralink/rt2x00/rt2x00eeprom.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2x00eeprom.c
@@ -10,11 +10,69 @@
 
 #include <linux/kernel.h>
 #include <linux/module.h>
+#if IS_ENABLED(CONFIG_MTD)
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#endif
 #include <linux/of.h>
 
 #include "rt2x00.h"
 #include "rt2x00soc.h"
 
+#if IS_ENABLED(CONFIG_MTD)
+static int rt2800lib_read_eeprom_mtd(struct rt2x00_dev *rt2x00dev)
+{
+	int ret = -EINVAL;
+#ifdef CONFIG_OF
+	struct device_node *np = rt2x00dev->dev->of_node, *mtd_np = NULL;
+	int size, offset = 0;
+	struct mtd_info *mtd;
+	const char *part;
+	const __be32 *list;
+	phandle phandle;
+	size_t retlen;
+
+	list = of_get_property(np, "ralink,mtd-eeprom", &size);
+	if (!list)
+		return -ENOENT;
+
+	phandle = be32_to_cpup(list++);
+	if (phandle)
+		mtd_np = of_find_node_by_phandle(phandle);
+	if (!mtd_np) {
+		dev_err(rt2x00dev->dev, "failed to load mtd phandle\n");
+		return -EINVAL;
+	}
+
+	part = of_get_property(mtd_np, "label", NULL);
+	if (!part)
+		part = mtd_np->name;
+
+	mtd = get_mtd_device_nm(part);
+	if (IS_ERR(mtd)) {
+		dev_err(rt2x00dev->dev, "failed to get mtd device \"%s\"\n", part);
+		return PTR_ERR(mtd);
+	}
+
+	if (size > sizeof(*list))
+		offset = be32_to_cpup(list);
+
+	ret = mtd_read(mtd, offset, rt2x00dev->ops->eeprom_size,
+		       &retlen, (u_char *)rt2x00dev->eeprom);
+	put_mtd_device(mtd);
+
+	if (retlen != rt2x00dev->ops->eeprom_size || ret) {
+		dev_err(rt2x00dev->dev, "failed to load eeprom from device \"%s\"\n", part);
+		return ret;
+	}
+
+	dev_info(rt2x00dev->dev, "loaded eeprom from mtd device \"%s\"\n", part);
+#endif
+
+	return ret;
+}
+#endif
+
 static const char *
 rt2x00lib_get_eeprom_file_name(struct rt2x00_dev *rt2x00dev)
 {
@@ -83,6 +141,14 @@ err_exit:
 
 int rt2x00lib_read_eeprom(struct rt2x00_dev *rt2x00dev)
 {
+	int ret;
+
+#if IS_ENABLED(CONFIG_MTD)
+	ret = rt2800lib_read_eeprom_mtd(rt2x00dev);
+	if (!ret)
+		return 0;
+#endif
+
 	return rt2x00lib_read_eeprom_file(rt2x00dev);
 }
 EXPORT_SYMBOL_GPL(rt2x00lib_read_eeprom);