Add a function to modify inplace a property starting from a given index.
This is especially useful when the property is an array of values, and you
want to update one of them without changing the DT size.
Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
---
include/libfdt.h | 34 +++++++++++++++++++++++++++++++---
lib/libfdt/fdt_wip.c | 13 ++++++++-----
2 files changed, 39 insertions(+), 8 deletions(-)
diff --git a/include/libfdt.h b/include/libfdt.h
index 4643be5adf39..2c8a42bcb667 100644
--- a/include/libfdt.h
+++ b/include/libfdt.h
@@ -1032,6 +1032,27 @@ int fdt_size_cells(const void *fdt, int nodeoffset);
/* Write-in-place functions */
/**********************************************************************/
+/**
+ * fdt_setprop_inplace_namelen_by_index - change a property's value,
+ * but not its size
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @namelen: number of characters of name to consider
+ * @index: index of the property to change in the array
+ * @val: pointer to data to replace the property value with
+ * @len: length of the property value
+ *
+ * Identical to fdt_setprop_inplace(), but modifies the given property
+ * starting from the given index, and using only the first characters
+ * of the name. It is useful when you want to manipulate only one value of
+ * an array and you have a string that doesn't end with \0.
+ */
+int fdt_setprop_inplace_namelen_by_index(void *fdt, int nodeoffset,
+ const char *name, int namelen,
+ uint32_t index, const void *val,
+ int len);
+
/**
* fdt_setprop_inplace - change a property's value, but not its size
* @fdt: pointer to the device tree blob
@@ -1060,8 +1081,13 @@ int fdt_size_cells(const void *fdt, int nodeoffset);
* -FDT_ERR_BADSTRUCTURE,
* -FDT_ERR_TRUNCATED, standard meanings
*/
-int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
- const void *val, int len);
+static inline int fdt_setprop_inplace(void *fdt, int nodeoffset,
+ const char *name, const void *val,
+ int len)
+{
+ return fdt_setprop_inplace_namelen_by_index(fdt, nodeoffset, name,
+ strlen(name), 0, val, len);
+}
/**
* fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
@@ -1095,7 +1121,9 @@ static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
const char *name, uint32_t val)
{
fdt32_t tmp = cpu_to_fdt32(val);
- return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
+ return fdt_setprop_inplace_namelen_by_index(fdt, nodeoffset,
+ name, strlen(name),
+ 0, &tmp, sizeof(tmp));
}
/**
diff --git a/lib/libfdt/fdt_wip.c b/lib/libfdt/fdt_wip.c
index 9fe988655fe3..737769fa59e2 100644
--- a/lib/libfdt/fdt_wip.c
+++ b/lib/libfdt/fdt_wip.c
@@ -14,20 +14,23 @@
#include "libfdt_internal.h"
-int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
- const void *val, int len)
+int fdt_setprop_inplace_namelen_by_index(void *fdt, int nodeoffset,
+ const char *name, int namelen,
+ uint32_t index, const void *val,
+ int len)
{
void *propval;
int proplen;
- propval = fdt_getprop_w(fdt, nodeoffset, name, &proplen);
+ propval = fdt_getprop_namelen_w(fdt, nodeoffset, name, namelen,
+ &proplen);
if (!propval)
return proplen;
- if (proplen != len)
+ if (proplen < (len + index))
return -FDT_ERR_NOSPACE;
- memcpy(propval, val, len);
+ memcpy(propval + index, val, len);
return 0;
}
--
2.9.0
--
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