Re: [PATCH net-next] net: wan: framer: Simplify API framer_provider_simple_of_xlate() implementation
From: Simon Horman
Date: Thu Dec 12 2024 - 11:52:00 EST
On Wed, Dec 11, 2024 at 09:28:20PM +0800, Zijun Hu wrote:
> From: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
>
> Simplify framer_provider_simple_of_xlate() implementation by API
> class_find_device_by_of_node().
>
> Also correct comments to mark its parameter @dev as unused instead of
> @args in passing.
>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
> ---
> drivers/net/wan/framer/framer-core.c | 20 +++++++-------------
> 1 file changed, 7 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/net/wan/framer/framer-core.c b/drivers/net/wan/framer/framer-core.c
> index f547c22e26ac2b9986e48ed77143f12a0c8f62fb..7b369d9c41613314860753b7927b209e58f45a91 100644
> --- a/drivers/net/wan/framer/framer-core.c
> +++ b/drivers/net/wan/framer/framer-core.c
> @@ -732,8 +732,8 @@ EXPORT_SYMBOL_GPL(devm_framer_create);
>
> /**
> * framer_provider_simple_of_xlate() - returns the framer instance from framer provider
> - * @dev: the framer provider device
> - * @args: of_phandle_args (not used here)
> + * @dev: the framer provider device (not used here)
> + * @args: of_phandle_args
> *
> * Intended to be used by framer provider for the common case where #framer-cells is
> * 0. For other cases where #framer-cells is greater than '0', the framer provider
> @@ -743,20 +743,14 @@ EXPORT_SYMBOL_GPL(devm_framer_create);
> struct framer *framer_provider_simple_of_xlate(struct device *dev,
> const struct of_phandle_args *args)
> {
> - struct class_dev_iter iter;
> - struct framer *framer;
> -
> - class_dev_iter_init(&iter, &framer_class, NULL, NULL);
> - while ((dev = class_dev_iter_next(&iter))) {
> - framer = dev_to_framer(dev);
> - if (args->np != framer->dev.of_node)
> - continue;
> + struct device *target_dev;
>
> - class_dev_iter_exit(&iter);
> - return framer;
> + target_dev = class_find_device_by_of_node(&framer_class, args->np);
> + if (target_dev) {
> + put_device(target_dev);
> + return dev_to_framer(target_dev);
> }
>
> - class_dev_iter_exit(&iter);
> return ERR_PTR(-ENODEV);
Hi Zijun Hu,
FWIIW, I think it would be more idiomatic to have the non-error path in the
main flow of execution, something like this (completely untested!):
target_dev = class_find_device_by_of_node(&framer_class, args->np);
if (!target_dev)
return ERR_PTR(-ENODEV);
put_device(target_dev);
return dev_to_framer(target_dev);
Also, is it safe to put_device(target_dev) before
passing target_dev to dev_to_framer() ?
> }
> EXPORT_SYMBOL_GPL(framer_provider_simple_of_xlate);
...