Blame view

kernel/linux-imx6_3.14.28/drivers/of/of_mtd.c 1.99 KB
6b13f685e   김민수   BSP 최초 추가
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
  /*
   * Copyright 2012 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
   *
   * OF helpers for mtd.
   *
   * This file is released under the GPLv2
   *
   */
  #include <linux/kernel.h>
  #include <linux/of_mtd.h>
  #include <linux/mtd/nand.h>
  #include <linux/export.h>
  
  /**
   * It maps 'enum nand_ecc_modes_t' found in include/linux/mtd/nand.h
   * into the device tree binding of 'nand-ecc', so that MTD
   * device driver can get nand ecc from device tree.
   */
  static const char *nand_ecc_modes[] = {
  	[NAND_ECC_NONE]		= "none",
  	[NAND_ECC_SOFT]		= "soft",
  	[NAND_ECC_HW]		= "hw",
  	[NAND_ECC_HW_SYNDROME]	= "hw_syndrome",
  	[NAND_ECC_HW_OOB_FIRST]	= "hw_oob_first",
  	[NAND_ECC_SOFT_BCH]	= "soft_bch",
  };
  
  /**
   * of_get_nand_ecc_mode - Get nand ecc mode for given device_node
   * @np:	Pointer to the given device_node
   *
   * The function gets ecc mode string from property 'nand-ecc-mode',
   * and return its index in nand_ecc_modes table, or errno in error case.
   */
  int of_get_nand_ecc_mode(struct device_node *np)
  {
  	const char *pm;
  	int err, i;
  
  	err = of_property_read_string(np, "nand-ecc-mode", &pm);
  	if (err < 0)
  		return err;
  
  	for (i = 0; i < ARRAY_SIZE(nand_ecc_modes); i++)
  		if (!strcasecmp(pm, nand_ecc_modes[i]))
  			return i;
  
  	return -ENODEV;
  }
  EXPORT_SYMBOL_GPL(of_get_nand_ecc_mode);
  
  /**
   * of_get_nand_bus_width - Get nand bus witdh for given device_node
   * @np:	Pointer to the given device_node
   *
   * return bus width option, or errno in error case.
   */
  int of_get_nand_bus_width(struct device_node *np)
  {
  	u32 val;
  
  	if (of_property_read_u32(np, "nand-bus-width", &val))
  		return 8;
  
  	switch(val) {
  	case 8:
  	case 16:
  		return val;
  	default:
  		return -EIO;
  	}
  }
  EXPORT_SYMBOL_GPL(of_get_nand_bus_width);
  
  /**
   * of_get_nand_on_flash_bbt - Get nand on flash bbt for given device_node
   * @np:	Pointer to the given device_node
   *
   * return true if present false other wise
   */
  bool of_get_nand_on_flash_bbt(struct device_node *np)
  {
  	return of_property_read_bool(np, "nand-on-flash-bbt");
  }
  EXPORT_SYMBOL_GPL(of_get_nand_on_flash_bbt);