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| author | Thierry Reding <treding@nvidia.com> | 2019-03-26 16:33:00 +0100 |
|---|---|---|
| committer | Sebastian Huber <sebastian.huber@embedded-brains.de> | 2020-03-02 07:52:19 +0100 |
| commit | 6505fe0edea8762955e3c8dc86801bb0679ba4f7 (patch) | |
| tree | 3645c16d1510b24c719d1d23391bb79653ed964c /cpukit/include/libfdt.h | |
| parent | libfdt: add fdt_append_addrrange() (diff) | |
| download | rtems-6505fe0edea8762955e3c8dc86801bb0679ba4f7.tar.bz2 | |
libfdt: Add new maximum phandle lookup function
The fdt_get_max_phandle() function has some shortcomings. On one hand
it returns just a uint32_t which means to check for the "negative"
error code a caller has to explicitly check against the error code
(uint32_t)-1. In addition, the -1 is the only error code that can be
returned, so a caller cannot tell the difference between the various
failures.
Fix this by adding a new fdt_find_max_phandle() function that returns an
error code on failure and 0 on success, just like other APIs, and stores
the maximum phandle value in an output argument on success.
This also refactors fdt_get_max_phandle() to use the new function. Add a
note pointing out that the new fdt_find_max_phandle() function should be
preferred over fdt_get_max_phandle().
Signed-off-by: Thierry Reding <treding@nvidia.com>
Message-Id: <20190326153302.17109-1-thierry.reding@gmail.com>
[dwg: Reword for some inaccuracies in the commit message]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Diffstat (limited to '')
| -rw-r--r-- | cpukit/include/libfdt.h | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/cpukit/include/libfdt.h b/cpukit/include/libfdt.h index e70f5bf7e8..e1498c3c21 100644 --- a/cpukit/include/libfdt.h +++ b/cpukit/include/libfdt.h @@ -386,6 +386,20 @@ const char *fdt_get_string(const void *fdt, int stroffset, int *lenp); const char *fdt_string(const void *fdt, int stroffset); /** + * fdt_find_max_phandle - find and return the highest phandle in a tree + * @fdt: pointer to the device tree blob + * @phandle: return location for the highest phandle value found in the tree + * + * fdt_find_max_phandle() finds the highest phandle value in the given device + * tree. The value returned in @phandle is only valid if the function returns + * success. + * + * returns: + * 0 on success or a negative error code on failure + */ +int fdt_find_max_phandle(const void *fdt, uint32_t *phandle); + +/** * fdt_get_max_phandle - retrieves the highest phandle in a tree * @fdt: pointer to the device tree blob * @@ -393,6 +407,8 @@ const char *fdt_string(const void *fdt, int stroffset); * device tree. This will ignore badly formatted phandles, or phandles * with a value of 0 or -1. * + * This function is deprecated in favour of fdt_find_max_phandle(). + * * returns: * the highest phandle on success * 0, if no phandle was found in the device tree |