From 0460e9868fd82a3675db02f6ceb6edfd8501c194 Mon Sep 17 00:00:00 2001 From: Boris BREZILLON 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 Signed-off-by: Hans de Goede --- 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 diff --git a/drivers/mtd/nand/ofnandpart.c b/drivers/mtd/nand/ofnandpart.c new file mode 100644 index 0000000..293daee --- /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 + * + * 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 +#include +#include +#include +#include +#include + +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"); diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h index 510e09b..5616f51 100644 --- a/include/linux/mtd/nand.h +++ b/include/linux/mtd/nand.h @@ -1013,6 +1013,23 @@ static inline int jedec_feature(struct nand_chip *chip) : 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 *