From 36ad18a6db0eec546b83e6500ceb7593be53a1ed Mon Sep 17 00:00:00 2001 From: Minghuan Lian Date: Mon, 27 Aug 2012 19:38:59 -0500 Subject: libfdt: Add support for appending the values to a existing property Some properties may contain multiple values, these values may need to be added to the property respectively. this patch provides this functionality. The main purpose of fdt_append_prop() is to append the values to a existing property, or create a new property if it dose not exist. Signed-off-by: Minghuan Lian Signed-off-by: David Gibson diff --git a/include/libfdt.h b/include/libfdt.h index de82ed5..78798e8 100644 --- a/include/libfdt.h +++ b/include/libfdt.h @@ -1134,6 +1134,101 @@ static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name, fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1) /** + * fdt_appendprop - append to or create a property + * @fdt: pointer to the device tree blob + * @nodeoffset: offset of the node whose property to change + * @name: name of the property to append to + * @val: pointer to data to append to the property value + * @len: length of the data to append to the property value + * + * fdt_appendprop() appends the value to the named property in the + * given node, creating the property if it does not already exist. + * + * This function may insert data into the blob, and will therefore + * change the offsets of some existing nodes. + * + * returns: + * 0, on success + * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to + * contain the new property value + * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag + * -FDT_ERR_BADLAYOUT, + * -FDT_ERR_BADMAGIC, + * -FDT_ERR_BADVERSION, + * -FDT_ERR_BADSTATE, + * -FDT_ERR_BADSTRUCTURE, + * -FDT_ERR_BADLAYOUT, + * -FDT_ERR_TRUNCATED, standard meanings + */ +int fdt_appendprop(void *fdt, int nodeoffset, const char *name, + const void *val, int len); + +/** + * fdt_appendprop_cell - append a single cell value to a property + * @fdt: pointer to the device tree blob + * @nodeoffset: offset of the node whose property to change + * @name: name of the property to change + * @val: 32-bit integer value to append to the property (native endian) + * + * fdt_appendprop_cell() appends the given cell value (converting to + * big-endian if necessary) to the value of the named property in the + * given node, or creates a new property with that value if it does + * not already exist. + * + * This function may insert data into the blob, and will therefore + * change the offsets of some existing nodes. + * + * returns: + * 0, on success + * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to + * contain the new property value + * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag + * -FDT_ERR_BADLAYOUT, + * -FDT_ERR_BADMAGIC, + * -FDT_ERR_BADVERSION, + * -FDT_ERR_BADSTATE, + * -FDT_ERR_BADSTRUCTURE, + * -FDT_ERR_BADLAYOUT, + * -FDT_ERR_TRUNCATED, standard meanings + */ +static inline int fdt_appendprop_cell(void *fdt, int nodeoffset, + const char *name, uint32_t val) +{ + val = cpu_to_fdt32(val); + return fdt_appendprop(fdt, nodeoffset, name, &val, sizeof(val)); +} + +/** + * fdt_appendprop_string - append a string to a property + * @fdt: pointer to the device tree blob + * @nodeoffset: offset of the node whose property to change + * @name: name of the property to change + * @str: string value to append to the property + * + * fdt_appendprop_string() appends the given string to the value of + * the named property in the given node, or creates a new property + * with that value if it does not already exist. + * + * This function may insert data into the blob, and will therefore + * change the offsets of some existing nodes. + * + * returns: + * 0, on success + * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to + * contain the new property value + * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag + * -FDT_ERR_BADLAYOUT, + * -FDT_ERR_BADMAGIC, + * -FDT_ERR_BADVERSION, + * -FDT_ERR_BADSTATE, + * -FDT_ERR_BADSTRUCTURE, + * -FDT_ERR_BADLAYOUT, + * -FDT_ERR_TRUNCATED, standard meanings + */ +#define fdt_appendprop_string(fdt, nodeoffset, name, str) \ + fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1) + +/** * fdt_delprop - delete a property * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to nop diff --git a/lib/libfdt/fdt_rw.c b/lib/libfdt/fdt_rw.c index 5c27a67..5ed23d6 100644 --- a/lib/libfdt/fdt_rw.c +++ b/lib/libfdt/fdt_rw.c @@ -293,6 +293,33 @@ int fdt_setprop(void *fdt, int nodeoffset, const char *name, return 0; } +int fdt_appendprop(void *fdt, int nodeoffset, const char *name, + const void *val, int len) +{ + struct fdt_property *prop; + int err, oldlen, newlen; + + FDT_RW_CHECK_HEADER(fdt); + + prop = fdt_get_property_w(fdt, nodeoffset, name, &oldlen); + if (prop) { + newlen = len + oldlen; + err = _fdt_splice_struct(fdt, prop->data, + FDT_TAGALIGN(oldlen), + FDT_TAGALIGN(newlen)); + if (err) + return err; + prop->len = cpu_to_fdt32(newlen); + memcpy(prop->data + oldlen, val, len); + } else { + err = _fdt_add_property(fdt, nodeoffset, name, len, &prop); + if (err) + return err; + memcpy(prop->data, val, len); + } + return 0; +} + int fdt_delprop(void *fdt, int nodeoffset, const char *name) { struct fdt_property *prop; -- cgit v0.10.2