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From 0460e9868fd82a3675db02f6ceb6edfd8501c194 Mon Sep 17 00:00:00 2001
From: Boris BREZILLON <boris.brezillon@free-electrons.com>
Date: Mon, 28 Jul 2014 14:31:42 +0200
Subject: [PATCH] mtd: nand: Add DT NAND partition parser
Add a of_nandpart_parse function to help parsing NAND partitions from DT.
This function should be called from NAND controller drivers just after the
nand_scan_tail in place of mtd_device_parse_register.
The caller can specify a parser function to retrieve HW specific
informations from the DT.
Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
drivers/mtd/nand/ofnandpart.c | 104 ++++++++++++++++++++++++++++++++++++++++++
include/linux/mtd/nand.h | 17 +++++++
2 files changed, 121 insertions(+)
create mode 100644 drivers/mtd/nand/ofnandpart.c
--- /dev/null
+++ b/drivers/mtd/nand/ofnandpart.c
@@ -0,0 +1,104 @@
+/*
+ * NAND Flash partitions described by the OF (or flattened) device tree
+ *
+ * Copyright © 2014 Boris BREZILLON <b.brezillon.dev@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/mtd/mtd.h>
+#include <linux/slab.h>
+#include <linux/mtd/nand.h>
+
+static inline bool node_has_compatible(struct device_node *pp)
+{
+ return of_get_property(pp, "compatible", NULL);
+}
+
+int ofnandpart_parse(struct mtd_info *master,
+ const struct ofnandpart_data *data)
+{
+ struct device_node *node;
+ const char *partname;
+ struct device_node *pp;
+ int i;
+
+ if (!data)
+ return 0;
+
+ node = data->node;
+ if (!node)
+ return 0;
+
+ i = 0;
+ for_each_child_of_node(node, pp) {
+ const __be32 *reg;
+ int len;
+ int a_cells, s_cells;
+ uint64_t offset, size;
+ uint32_t mask_flags = 0;
+ struct nand_part *part;
+
+ if (node_has_compatible(pp))
+ continue;
+
+ reg = of_get_property(pp, "reg", &len);
+ if (!reg)
+ continue;
+
+ a_cells = of_n_addr_cells(pp);
+ s_cells = of_n_size_cells(pp);
+ offset = of_read_number(reg, a_cells);
+ size = of_read_number(reg + a_cells, s_cells);
+
+ partname = of_get_property(pp, "label", &len);
+ if (!partname)
+ partname = of_get_property(pp, "name", &len);
+
+ if (of_get_property(pp, "read-only", &len))
+ mask_flags |= MTD_WRITEABLE;
+
+ if (of_get_property(pp, "lock", &len))
+ mask_flags |= MTD_POWERUP_LOCK;
+
+ if (data->parse)
+ part = data->parse(data->priv, master, pp);
+ else
+ part = nandpart_alloc();
+
+ if (IS_ERR(part))
+ continue;
+
+ part->offset = offset;
+ part->master = master;
+ part->mtd.name = partname;
+ part->mtd.size = size;
+ part->mtd.flags = mask_flags;
+
+ if (nand_add_partition(master, part)) {
+ if (part->release)
+ part->release(part);
+ continue;
+ }
+
+ i++;
+ }
+
+ if (!i) {
+ of_node_put(pp);
+ pr_err("No valid partition found on %s\n", node->full_name);
+ }
+
+ return i;
+}
+EXPORT_SYMBOL(ofnandpart_parse);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Parser for NAND flash partitioning information in device tree");
+MODULE_AUTHOR("Boris BREZILLON");
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -1014,6 +1014,23 @@ static inline int jedec_feature(struct n
: 0;
}
+/**
+ * struct ofnandpart_data - struct used to retrieve NAND partitions from a DT
+ * node
+ * @parse: driver specific parser function
+ * @priv: driver private data
+ * @node: OF node containing NAND partitions
+ */
+struct ofnandpart_data {
+ struct nand_part *(*parse)(void *priv, struct mtd_info *master,
+ struct device_node *pp);
+ void *priv;
+ struct device_node *node;
+};
+
+int ofnandpart_parse(struct mtd_info *master,
+ const struct ofnandpart_data *data);
+
/*
* struct nand_sdr_timings - SDR NAND chip timings
*
|
