diff options
Diffstat (limited to 'drivers/mtd/ofpart.c')
| -rw-r--r-- | drivers/mtd/ofpart.c | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/drivers/mtd/ofpart.c b/drivers/mtd/ofpart.c new file mode 100644 index 000000000..aa26c32e1 --- /dev/null +++ b/drivers/mtd/ofpart.c @@ -0,0 +1,198 @@ +/* + * Flash partitions described by the OF (or flattened) device tree + * + * Copyright © 2006 MontaVista Software Inc. + * Author: Vitaly Wool <vwool@ru.mvista.com> + * + * Revised to handle newer style flash binding by: + * Copyright © 2007 David Gibson, IBM Corporation. + * + * 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/partitions.h> + +static bool node_has_compatible(struct device_node *pp) +{ + return of_get_property(pp, "compatible", NULL); +} + +static int parse_ofpart_partitions(struct mtd_info *master, + struct mtd_partition **pparts, + struct mtd_part_parser_data *data) +{ + struct device_node *node; + const char *partname; + struct device_node *pp; + int nr_parts, i; + + + if (!data) + return 0; + + node = data->of_node; + if (!node) + return 0; + + /* First count the subnodes */ + nr_parts = 0; + for_each_child_of_node(node, pp) { + if (node_has_compatible(pp)) + continue; + + nr_parts++; + } + + if (nr_parts == 0) + return 0; + + *pparts = kzalloc(nr_parts * sizeof(**pparts), GFP_KERNEL); + if (!*pparts) + return -ENOMEM; + + i = 0; + for_each_child_of_node(node, pp) { + const __be32 *reg; + int len; + int a_cells, s_cells; + + if (node_has_compatible(pp)) + continue; + + reg = of_get_property(pp, "reg", &len); + if (!reg) { + nr_parts--; + continue; + } + + a_cells = of_n_addr_cells(pp); + s_cells = of_n_size_cells(pp); + (*pparts)[i].offset = of_read_number(reg, a_cells); + (*pparts)[i].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); + (*pparts)[i].name = partname; + + if (of_get_property(pp, "read-only", &len)) + (*pparts)[i].mask_flags |= MTD_WRITEABLE; + + if (of_get_property(pp, "lock", &len)) + (*pparts)[i].mask_flags |= MTD_POWERUP_LOCK; + + i++; + } + + if (!i) { + of_node_put(pp); + pr_err("No valid partition found on %s\n", node->full_name); + kfree(*pparts); + *pparts = NULL; + return -EINVAL; + } + + return nr_parts; +} + +static struct mtd_part_parser ofpart_parser = { + .owner = THIS_MODULE, + .parse_fn = parse_ofpart_partitions, + .name = "ofpart", +}; + +static int parse_ofoldpart_partitions(struct mtd_info *master, + struct mtd_partition **pparts, + struct mtd_part_parser_data *data) +{ + struct device_node *dp; + int i, plen, nr_parts; + const struct { + __be32 offset, len; + } *part; + const char *names; + + if (!data) + return 0; + + dp = data->of_node; + if (!dp) + return 0; + + part = of_get_property(dp, "partitions", &plen); + if (!part) + return 0; /* No partitions found */ + + pr_warning("Device tree uses obsolete partition map binding: %s\n", + dp->full_name); + + nr_parts = plen / sizeof(part[0]); + + *pparts = kzalloc(nr_parts * sizeof(*(*pparts)), GFP_KERNEL); + if (!*pparts) + return -ENOMEM; + + names = of_get_property(dp, "partition-names", &plen); + + for (i = 0; i < nr_parts; i++) { + (*pparts)[i].offset = be32_to_cpu(part->offset); + (*pparts)[i].size = be32_to_cpu(part->len) & ~1; + /* bit 0 set signifies read only partition */ + if (be32_to_cpu(part->len) & 1) + (*pparts)[i].mask_flags = MTD_WRITEABLE; + + if (names && (plen > 0)) { + int len = strlen(names) + 1; + + (*pparts)[i].name = names; + plen -= len; + names += len; + } else { + (*pparts)[i].name = "unnamed"; + } + + part++; + } + + return nr_parts; +} + +static struct mtd_part_parser ofoldpart_parser = { + .owner = THIS_MODULE, + .parse_fn = parse_ofoldpart_partitions, + .name = "ofoldpart", +}; + +static int __init ofpart_parser_init(void) +{ + register_mtd_parser(&ofpart_parser); + register_mtd_parser(&ofoldpart_parser); + return 0; +} + +static void __exit ofpart_parser_exit(void) +{ + deregister_mtd_parser(&ofpart_parser); + deregister_mtd_parser(&ofoldpart_parser); +} + +module_init(ofpart_parser_init); +module_exit(ofpart_parser_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Parser for MTD partitioning information in device tree"); +MODULE_AUTHOR("Vitaly Wool, David Gibson"); +/* + * When MTD core cannot find the requested parser, it tries to load the module + * with the same name. Since we provide the ofoldpart parser, we should have + * the corresponding alias. + */ +MODULE_ALIAS("ofoldpart"); |