From 770d7c39af940da24dd4c2c048576d778ac0abd4 Mon Sep 17 00:00:00 2001 From: Jean-Christophe PLAGNIOL-VILLARD Date: Sat, 28 Jan 2012 12:12:36 +0800 Subject: of/mtd/nand: add generic bindings and helpers - nand-ecc-mode : String, operation mode of the NAND ecc mode. Supported values are: "none", "soft", "hw", "hw_syndrome", "hw_oob_first", "soft_bch". - nand-bus-width : 8 or 16 bus width if not present 8 - nand-on-flash-bbt: boolean to enable on flash bbt option if not present false Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD Acked-by: Grant Likely Acked-by: Stefan Roese --- drivers/of/of_mtd.c | 85 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 85 insertions(+) create mode 100644 drivers/of/of_mtd.c (limited to 'drivers/of/of_mtd.c') diff --git a/drivers/of/of_mtd.c b/drivers/of/of_mtd.c new file mode 100644 index 0000000..e7cad62 --- /dev/null +++ b/drivers/of/of_mtd.c @@ -0,0 +1,85 @@ +/* + * Copyright 2012 Jean-Christophe PLAGNIOL-VILLARD + * + * OF helpers for mtd. + * + * This file is released under the GPLv2 + * + */ +#include +#include +#include +#include + +/** + * 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. + */ +const 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); -- cgit v1.1