drivers/mtd/ofpart.c

   1 /*
   2  * Flash partitions described by the OF (or flattened) device tree
   3  *
   4  * Copyright (C) 2006 MontaVista Software Inc.
   5  * Author: Vitaly Wool <vwool@ru.mvista.com>
   6  *
   7  * Revised to handle newer style flash binding by:
   8  *   Copyright (C) 2007 David Gibson, IBM Corporation.
   9  *
  10  * This program is free software; you can redistribute  it and/or modify it
  11  * under  the terms of  the GNU General  Public License as published by the
  12  * Free Software Foundation;  either version 2 of the  License, or (at your
  13  * option) any later version.
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/init.h>
  18 #include <linux/of.h>
  19 #include <linux/mtd/mtd.h>
  20 #include <linux/mtd/partitions.h>
  21
  22 int __devinit of_mtd_parse_partitions(struct device *dev,
  23                                       struct device_node *node,
  24                                       struct mtd_partition **pparts)
  25 {
  26         const char *partname;
  27         struct device_node *pp;
  28         int nr_parts, i;
  29
  30         /* First count the subnodes */
  31         pp = NULL;
  32         nr_parts = 0;
  33         while ((pp = of_get_next_child(node, pp)))
  34                 nr_parts++;
  35
  36         if (nr_parts == 0)
  37                 return 0;
  38
  39         *pparts = kzalloc(nr_parts * sizeof(**pparts), GFP_KERNEL);
  40         if (!*pparts)
  41                 return -ENOMEM;
  42
  43         pp = NULL;
  44         i = 0;
  45         while ((pp = of_get_next_child(node, pp))) {
  46                 const u32 *reg;
  47                 int len;
  48
  49                 reg = of_get_property(pp, "reg", &len);
  50                 if (!reg) {
  51                         nr_parts--;
  52                         continue;
  53                 }
  54
  55                 (*pparts)[i].offset = reg[0];
  56                 (*pparts)[i].size = reg[1];
  57
  58                 partname = of_get_property(pp, "label", &len);
  59                 if (!partname)
  60                         partname = of_get_property(pp, "name", &len);
  61                 (*pparts)[i].name = (char *)partname;
  62
  63                 if (of_get_property(pp, "read-only", &len))
  64                         (*pparts)[i].mask_flags = MTD_WRITEABLE;
  65
  66                 i++;
  67         }
  68
  69         if (!i) {
  70                 of_node_put(pp);
  71                 dev_err(dev, "No valid partition found on %s\n", node->full_name);
  72                 kfree(*pparts);
  73                 *pparts = NULL;
  74                 return -EINVAL;
  75         }
  76
  77         return nr_parts;
  78 }
  79 EXPORT_SYMBOL(of_mtd_parse_partitions);
  80
  81 MODULE_LICENSE("GPL");