Re: [PATCH 05/31] opp: Add devres wrapper for dev_pm_opp_register_notifier

Viresh Kumar
2021-01-04T07:17:02Z

On 01-01-21, 16:54, Yangtao Li wrote:
> Add devres wrapper for dev_pm_opp_register_notifier() to simplify driver
> code.
>
> Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
> ---
> drivers/opp/core.c | 38 ++++++++++++++++++++++++++++++++++++++
> include/linux/pm_opp.h | 6 ++++++
> 2 files changed, 44 insertions(+)
>
> diff --git a/drivers/opp/core.c b/drivers/opp/core.c
> index 6b83e373f0d8..ef3544f8cecd 100644
> --- a/drivers/opp/core.c
> +++ b/drivers/opp/core.c
> @@ -2599,6 +2599,44 @@ int dev_pm_opp_unregister_notifier(struct device *dev,
> }
> EXPORT_SYMBOL(dev_pm_opp_unregister_notifier);
>
> +static void devm_pm_opp_notifier_release(struct device *dev, void *res)
> +{
> + struct notifier_block *nb = *(struct notifier_block **)res;
> +
> + WARN_ON(dev_pm_opp_unregister_notifier(dev, nb));
> +}
> +
> +/**
> + * devm_pm_opp_register_notifier() - Register OPP notifier for the device
> + * @dev: Device for which notifier needs to be registered
> + * @nb: Notifier block to be registered
> + *
> + * Return: 0 on success or a negative error value.
> + *
> + * The notifier will be unregistered after the device is destroyed.
> + */
> +int devm_pm_opp_register_notifier(struct device *dev, struct notifier_block *nb)
> +{
> + struct notifier_block **ptr;
> + int ret;
> +
> + ptr = devres_alloc(devm_pm_opp_notifier_release, sizeof(*ptr), GFP_KERNEL);
> + if (!ptr)
> + return -ENOMEM;
> +
> + ret = dev_pm_opp_register_notifier(dev, nb);
> + if (ret) {
> + devres_free(ptr);
> + return ret;
> + }
> +
> + *ptr = nb;
> + devres_add(dev, ptr);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(devm_pm_opp_register_notifier);

I am not in favor of this patch, and it only has one user, which makes
it more unwanted.

--
viresh