1/*
 2 * Copyright 2012 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
 3 *
 4 * OF helpers for mtd.
 5 *
 6 * This file is released under the GPLv2
 7 *
 8 */
 9#include <linux/kernel.h>
10#include <linux/of_mtd.h>
11#include <linux/mtd/nand.h>
12#include <linux/export.h>
13
14/**
15 * It maps 'enum nand_ecc_modes_t' found in include/linux/mtd/nand.h
16 * into the device tree binding of 'nand-ecc', so that MTD
17 * device driver can get nand ecc from device tree.
18 */
19static const char *nand_ecc_modes[] = {
20	[NAND_ECC_NONE]		= "none",
21	[NAND_ECC_SOFT]		= "soft",
22	[NAND_ECC_HW]		= "hw",
23	[NAND_ECC_HW_SYNDROME]	= "hw_syndrome",
24	[NAND_ECC_HW_OOB_FIRST]	= "hw_oob_first",
25	[NAND_ECC_SOFT_BCH]	= "soft_bch",
26};
27
28/**
29 * of_get_nand_ecc_mode - Get nand ecc mode for given device_node
30 * @np:	Pointer to the given device_node
31 *
32 * The function gets ecc mode string from property 'nand-ecc-mode',
33 * and return its index in nand_ecc_modes table, or errno in error case.
34 */
35const int of_get_nand_ecc_mode(struct device_node *np)
36{
37	const char *pm;
38	int err, i;
39
40	err = of_property_read_string(np, "nand-ecc-mode", &pm);
41	if (err < 0)
42		return err;
43
44	for (i = 0; i < ARRAY_SIZE(nand_ecc_modes); i++)
45		if (!strcasecmp(pm, nand_ecc_modes[i]))
46			return i;
47
48	return -ENODEV;
49}
50EXPORT_SYMBOL_GPL(of_get_nand_ecc_mode);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
51
52/**
53 * of_get_nand_bus_width - Get nand bus witdh for given device_node
54 * @np:	Pointer to the given device_node
55 *
56 * return bus width option, or errno in error case.
57 */
58int of_get_nand_bus_width(struct device_node *np)
59{
60	u32 val;
61
62	if (of_property_read_u32(np, "nand-bus-width", &val))
63		return 8;
64
65	switch(val) {
66	case 8:
67	case 16:
68		return val;
69	default:
70		return -EIO;
71	}
72}
73EXPORT_SYMBOL_GPL(of_get_nand_bus_width);
74
75/**
76 * of_get_nand_on_flash_bbt - Get nand on flash bbt for given device_node
77 * @np:	Pointer to the given device_node
78 *
79 * return true if present false other wise
80 */
81bool of_get_nand_on_flash_bbt(struct device_node *np)
82{
83	return of_property_read_bool(np, "nand-on-flash-bbt");
84}
85EXPORT_SYMBOL_GPL(of_get_nand_on_flash_bbt);

  1/*
  2 * Copyright 2012 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
  3 *
  4 * OF helpers for mtd.
  5 *
  6 * This file is released under the GPLv2
  7 *
  8 */
  9#include <linux/kernel.h>
 10#include <linux/of_mtd.h>
 11#include <linux/mtd/nand.h>
 12#include <linux/export.h>
 13
 14/**
 15 * It maps 'enum nand_ecc_modes_t' found in include/linux/mtd/nand.h
 16 * into the device tree binding of 'nand-ecc', so that MTD
 17 * device driver can get nand ecc from device tree.
 18 */
 19static const char *nand_ecc_modes[] = {
 20	[NAND_ECC_NONE]		= "none",
 21	[NAND_ECC_SOFT]		= "soft",
 22	[NAND_ECC_HW]		= "hw",
 23	[NAND_ECC_HW_SYNDROME]	= "hw_syndrome",
 24	[NAND_ECC_HW_OOB_FIRST]	= "hw_oob_first",
 25	[NAND_ECC_SOFT_BCH]	= "soft_bch",
 26};
 27
 28/**
 29 * of_get_nand_ecc_mode - Get nand ecc mode for given device_node
 30 * @np:	Pointer to the given device_node
 31 *
 32 * The function gets ecc mode string from property 'nand-ecc-mode',
 33 * and return its index in nand_ecc_modes table, or errno in error case.
 34 */
 35int of_get_nand_ecc_mode(struct device_node *np)
 36{
 37	const char *pm;
 38	int err, i;
 39
 40	err = of_property_read_string(np, "nand-ecc-mode", &pm);
 41	if (err < 0)
 42		return err;
 43
 44	for (i = 0; i < ARRAY_SIZE(nand_ecc_modes); i++)
 45		if (!strcasecmp(pm, nand_ecc_modes[i]))
 46			return i;
 47
 48	return -ENODEV;
 49}
 50EXPORT_SYMBOL_GPL(of_get_nand_ecc_mode);
 51
 52/**
 53 * of_get_nand_ecc_step_size - Get ECC step size associated to
 54 * the required ECC strength (see below).
 55 * @np:	Pointer to the given device_node
 56 *
 57 * return the ECC step size, or errno in error case.
 58 */
 59int of_get_nand_ecc_step_size(struct device_node *np)
 60{
 61	int ret;
 62	u32 val;
 63
 64	ret = of_property_read_u32(np, "nand-ecc-step-size", &val);
 65	return ret ? ret : val;
 66}
 67EXPORT_SYMBOL_GPL(of_get_nand_ecc_step_size);
 68
 69/**
 70 * of_get_nand_ecc_strength - Get required ECC strength over the
 71 * correspnding step size as defined by 'nand-ecc-size'
 72 * @np:	Pointer to the given device_node
 73 *
 74 * return the ECC strength, or errno in error case.
 75 */
 76int of_get_nand_ecc_strength(struct device_node *np)
 77{
 78	int ret;
 79	u32 val;
 80
 81	ret = of_property_read_u32(np, "nand-ecc-strength", &val);
 82	return ret ? ret : val;
 83}
 84EXPORT_SYMBOL_GPL(of_get_nand_ecc_strength);
 85
 86/**
 87 * of_get_nand_bus_width - Get nand bus witdh for given device_node
 88 * @np:	Pointer to the given device_node
 89 *
 90 * return bus width option, or errno in error case.
 91 */
 92int of_get_nand_bus_width(struct device_node *np)
 93{
 94	u32 val;
 95
 96	if (of_property_read_u32(np, "nand-bus-width", &val))
 97		return 8;
 98
 99	switch(val) {
100	case 8:
101	case 16:
102		return val;
103	default:
104		return -EIO;
105	}
106}
107EXPORT_SYMBOL_GPL(of_get_nand_bus_width);
108
109/**
110 * of_get_nand_on_flash_bbt - Get nand on flash bbt for given device_node
111 * @np:	Pointer to the given device_node
112 *
113 * return true if present false other wise
114 */
115bool of_get_nand_on_flash_bbt(struct device_node *np)
116{
117	return of_property_read_bool(np, "nand-on-flash-bbt");
118}
119EXPORT_SYMBOL_GPL(of_get_nand_on_flash_bbt);