On Mon, Jul 11, 2016 at 09:56:22PM +0200, Maxime Ripard wrote:
> Add a function to modify inplace only a portion of a property..
>
> 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>
> Acked-by: Simon Glass <sjg@xxxxxxxxxxxx>
Reviewed-by: David Gibson <david@xxxxxxxxxxxxxxxxxxxxx>
Now it just needs some testcases..
> ---
> libfdt/fdt_wip.c | 29 +++++++++++++++++++++++++----
> libfdt/libfdt.h | 21 +++++++++++++++++++++
> 2 files changed, 46 insertions(+), 4 deletions(-)
>
> diff --git a/libfdt/fdt_wip.c b/libfdt/fdt_wip.c
> index c5bbb68d3273..fd53e0b67416 100644
> --- a/libfdt/fdt_wip.c
> +++ b/libfdt/fdt_wip.c
> @@ -55,21 +55,42 @@
>
> #include "libfdt_internal.h"
>
> +int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
> + const char *name, int namelen,
> + uint32_t index, const void *val,
> + int len)
> +{
> + void *propval;
> + int proplen;
> +
> + propval = fdt_getprop_namelen_w(fdt, nodeoffset, name, namelen,
> + &proplen);
> + if (!propval)
> + return proplen;
> +
> + if (proplen < (len + index))
> + return -FDT_ERR_NOSPACE;
> +
> + memcpy((unsigned char *)propval + index, val, len);
> + return 0;
> +}
> +
> int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
> const void *val, int len)
> {
> - void *propval;
> + const void *propval;
> int proplen;
>
> - propval = fdt_getprop_w(fdt, nodeoffset, name, &proplen);
> + propval = fdt_getprop(fdt, nodeoffset, name, &proplen);
> if (! propval)
> return proplen;
>
> if (proplen != len)
> return -FDT_ERR_NOSPACE;
>
> - memcpy(propval, val, len);
> - return 0;
> + return fdt_setprop_inplace_namelen_partial(fdt, nodeoffset, name,
> + strlen(name), 0,
> + val, len);
> }
>
> static void _fdt_nop_region(void *start, int len)
> diff --git a/libfdt/libfdt.h b/libfdt/libfdt.h
> index 1da2c540b607..a22a16b6878a 100644
> --- a/libfdt/libfdt.h
> +++ b/libfdt/libfdt.h
> @@ -1072,6 +1072,27 @@ int fdt_size_cells(const void *fdt, int nodeoffset);
> /* Write-in-place functions */
> /**********************************************************************/
>
> +/**
> + * fdt_setprop_inplace_namelen_partial - 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_partial(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
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
Attachment:
signature.asc
Description: PGP signature
