From ebaae1cd68cd79c7eee67c9c5c0fa45809e84525 Mon Sep 17 00:00:00 2001
From: Maikel Bloemendal <openwrt@maikelenyvonne.nl>
Date: Fri, 14 Nov 2014 17:06:00 +0000
Subject: [PATCH] owrt: lantiq: multiple flash

Concatenate multiple flash chips for lantiq-flash.

Signed-off-by: Maikel Bloemendal <openwrt@maikelenyvonne.nl>
---
 drivers/mtd/maps/lantiq-flash.c | 168 +++++++++++++++++++++-----------
 1 file changed, 109 insertions(+), 59 deletions(-)

--- a/drivers/mtd/maps/lantiq-flash.c
+++ b/drivers/mtd/maps/lantiq-flash.c
@@ -17,6 +17,7 @@
 #include <linux/mtd/cfi.h>
 #include <linux/platform_device.h>
 #include <linux/mtd/physmap.h>
+#include <linux/mtd/concat.h>
 #include <linux/of.h>
 
 #include <lantiq_soc.h>
@@ -36,13 +37,16 @@ enum {
 	LTQ_NOR_NORMAL
 };
 
+#define MAX_RESOURCES		4
+
 struct ltq_mtd {
-	struct resource *res;
-	struct mtd_info *mtd;
-	struct map_info *map;
+	struct mtd_info *mtd[MAX_RESOURCES];
+	struct mtd_info	*cmtd;
+	struct map_info map[MAX_RESOURCES];
 };
 
 static const char ltq_map_name[] = "ltq_nor";
+static const char * const ltq_probe_types[] = { "cmdlinepart", "ofpart", NULL };
 
 static map_word
 ltq_read16(struct map_info *map, unsigned long adr)
@@ -105,12 +109,41 @@ ltq_copy_to(struct map_info *map, unsign
 	spin_unlock_irqrestore(&ebu_lock, flags);
 }
 
+static void ltq_mtd_remove(struct platform_device *pdev)
+{
+	struct ltq_mtd *ltq_mtd = platform_get_drvdata(pdev);
+	int i;
+
+	if (ltq_mtd == NULL)
+		return;
+
+	if (ltq_mtd->cmtd) {
+		mtd_device_unregister(ltq_mtd->cmtd);
+		if (ltq_mtd->cmtd != ltq_mtd->mtd[0])
+			mtd_concat_destroy(ltq_mtd->cmtd);
+	}
+
+	for (i = 0; i < MAX_RESOURCES; i++) {
+		if (ltq_mtd->mtd[i] != NULL)
+			map_destroy(ltq_mtd->mtd[i]);
+	}
+
+	kfree(ltq_mtd);
+}
+
 static int
 ltq_mtd_probe(struct platform_device *pdev)
 {
 	struct ltq_mtd *ltq_mtd;
 	struct cfi_private *cfi;
-	int err;
+	int err = 0;
+	int i;
+	int devices_found = 0;
+
+	static const char *rom_probe_types[] = {
+		"cfi_probe", "jedec_probe", NULL
+	};
+	const char **type;
 
 	ltq_mtd = devm_kzalloc(&pdev->dev, sizeof(struct ltq_mtd), GFP_KERNEL);
 	if (!ltq_mtd)
@@ -118,68 +151,89 @@ ltq_mtd_probe(struct platform_device *pd
 
 	platform_set_drvdata(pdev, ltq_mtd);
 
-	ltq_mtd->map->virt = devm_platform_get_and_ioremap_resource(pdev, 0, &ltq_mtd->res);
-	if (IS_ERR(ltq_mtd->map->virt))
-		return PTR_ERR(ltq_mtd->map->virt);
-
-	ltq_mtd->map = devm_kzalloc(&pdev->dev, sizeof(struct map_info),
-				    GFP_KERNEL);
-	if (!ltq_mtd->map)
-		return -ENOMEM;
-
-	if (of_property_present(pdev->dev.of_node, "lantiq,noxip"))
-		ltq_mtd->map->phys = NO_XIP;
-	else
-		ltq_mtd->map->phys = ltq_mtd->res->start;
-	ltq_mtd->res->start;
-	ltq_mtd->map->size = resource_size(ltq_mtd->res);
-
-	ltq_mtd->map->name = ltq_map_name;
-	ltq_mtd->map->bankwidth = 2;
-	ltq_mtd->map->read = ltq_read16;
-	ltq_mtd->map->write = ltq_write16;
-	ltq_mtd->map->copy_from = ltq_copy_from;
-	ltq_mtd->map->copy_to = ltq_copy_to;
-
-	ltq_mtd->map->map_priv_1 = LTQ_NOR_PROBING;
-	ltq_mtd->mtd = do_map_probe("cfi_probe", ltq_mtd->map);
-	ltq_mtd->map->map_priv_1 = LTQ_NOR_NORMAL;
-
-	if (!ltq_mtd->mtd) {
-		dev_err(&pdev->dev, "probing failed\n");
-		return -ENXIO;
+	for (i = 0; i < pdev->num_resources; i++) {
+		printk(KERN_NOTICE "lantiq nor flash device: %.8llx at %.8llx\n",
+		       (unsigned long long)resource_size(&pdev->resource[i]),
+		       (unsigned long long)pdev->resource[i].start);
+	
+		if (!devm_request_mem_region(&pdev->dev,
+			pdev->resource[i].start,
+			resource_size(&pdev->resource[i]),
+			dev_name(&pdev->dev))) {
+			dev_err(&pdev->dev, "Could not reserve memory region\n");
+			return -ENOMEM;
+		}
+
+		ltq_mtd->map[i].name = ltq_map_name;
+		ltq_mtd->map[i].bankwidth = 2;
+		ltq_mtd->map[i].read = ltq_read16;
+		ltq_mtd->map[i].write = ltq_write16;
+		ltq_mtd->map[i].copy_from = ltq_copy_from;
+		ltq_mtd->map[i].copy_to = ltq_copy_to;
+
+		if (of_property_present(pdev->dev.of_node, "lantiq,noxip"))
+			ltq_mtd->map[i].phys = NO_XIP;
+		else
+			ltq_mtd->map[i].phys = pdev->resource[i].start;
+		ltq_mtd->map[i].size = resource_size(&pdev->resource[i]);
+		ltq_mtd->map[i].virt = devm_ioremap(&pdev->dev, pdev->resource[i].start,
+						 ltq_mtd->map[i].size);
+		if (IS_ERR(ltq_mtd->map[i].virt))
+			return PTR_ERR(ltq_mtd->map[i].virt);
+
+		if (ltq_mtd->map[i].virt == NULL) {
+			dev_err(&pdev->dev, "Failed to ioremap flash region\n");
+			err = PTR_ERR(ltq_mtd->map[i].virt);
+			goto err_out;
+		}
+
+		ltq_mtd->map[i].map_priv_1 = LTQ_NOR_PROBING;
+		for (type = rom_probe_types; !ltq_mtd->mtd[i] && *type; type++)
+			ltq_mtd->mtd[i] = do_map_probe(*type, &ltq_mtd->map[i]);
+		ltq_mtd->map[i].map_priv_1 = LTQ_NOR_NORMAL;
+
+		if (!ltq_mtd->mtd[i]) {
+			dev_err(&pdev->dev, "probing failed\n");
+			return -ENXIO;
+		} else {
+			devices_found++;
+		}
+
+		ltq_mtd->mtd[i]->owner = THIS_MODULE;
+		ltq_mtd->mtd[i]->dev.parent = &pdev->dev;
+
+		cfi = ltq_mtd->map[i].fldrv_priv;
+		cfi->addr_unlock1 ^= 1;
+		cfi->addr_unlock2 ^= 1;
 	}
 
-	ltq_mtd->mtd->dev.parent = &pdev->dev;
-	mtd_set_of_node(ltq_mtd->mtd, pdev->dev.of_node);
+	if (devices_found == 1) {
+		ltq_mtd->cmtd = ltq_mtd->mtd[0];
+	} else if (devices_found > 1) {
+		/*
+		 * We detected multiple devices. Concatenate them together.
+		 */
+		ltq_mtd->cmtd = mtd_concat_create(ltq_mtd->mtd, devices_found, dev_name(&pdev->dev));
+		if (ltq_mtd->cmtd == NULL)
+			err = -ENXIO;
+	}
 
-	cfi = ltq_mtd->map->fldrv_priv;
-	cfi->addr_unlock1 ^= 1;
-	cfi->addr_unlock2 ^= 1;
+	ltq_mtd->cmtd->dev.parent = &pdev->dev;
+	mtd_set_of_node(ltq_mtd->cmtd, pdev->dev.of_node);
 
-	err = mtd_device_register(ltq_mtd->mtd, NULL, 0);
+	err = mtd_device_register(ltq_mtd->cmtd, NULL, 0);
 	if (err) {
 		dev_err(&pdev->dev, "failed to add partitions\n");
-		goto err_destroy;
+		goto err_out;
 	}
 
 	return 0;
 
-err_destroy:
-	map_destroy(ltq_mtd->mtd);
+err_out:
+	ltq_mtd_remove(pdev);
 	return err;
 }
 
-static void ltq_mtd_remove(struct platform_device *pdev)
-{
-	struct ltq_mtd *ltq_mtd = platform_get_drvdata(pdev);
-
-	if (ltq_mtd && ltq_mtd->mtd) {
-		mtd_device_unregister(ltq_mtd->mtd);
-		map_destroy(ltq_mtd->mtd);
-	}
-}
-
 static const struct of_device_id ltq_mtd_match[] = {
 	{ .compatible = "lantiq,nor" },
 	{},
