diff options
| author | Théo Lebrun <theo.lebrun@bootlin.com> | 2024-12-30 14:30:27 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-12-30 15:35:59 +0100 |
| commit | 6fdbc7b9aa20b1db47d13a5f2a4d31fb2f8f3822 (patch) | |
| tree | 89ea57c912743cd99fcae272afbb26ed78ea66b0 | |
| parent | 62b467c65a7edbd4caac2214ec12da99e19e445e (diff) | |
nvmem: specify ->reg_read/reg_write() expected return values
Both ->reg_read() and ->reg_write() return values are not easy to
deduce. Explicit that they should return zero on success (and negative
values otherwise).
Such callbacks, in some alternative world, could return the number of
bytes in the success case. That would be translated to errors in the
nvmem core because of checks like:
ret = nvmem->reg_write(nvmem->priv, offset, val, bytes);
if (ret) {
// error case
}
This mistake is not just theoretical, see commit
28b008751aa2 ("nvmem: rmem: Fix return value of rmem_read()").
Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20241230143035.265518-4-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | include/linux/nvmem-provider.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/nvmem-provider.h b/include/linux/nvmem-provider.h index 3ebeaa0ded00..515676ebe598 100644 --- a/include/linux/nvmem-provider.h +++ b/include/linux/nvmem-provider.h @@ -92,8 +92,8 @@ struct nvmem_cell_info { * @read_only: Device is read-only. * @root_only: Device is accessibly to root only. * @of_node: If given, this will be used instead of the parent's of_node. - * @reg_read: Callback to read data. - * @reg_write: Callback to write data. + * @reg_read: Callback to read data; return zero if successful. + * @reg_write: Callback to write data; return zero if successful. * @size: Device size. * @word_size: Minimum read/write access granularity. * @stride: Minimum read/write access stride. |