Subject: [PATCH 3/4] PM / Domains: Improve error handling while adding/removing devices

From: [email-masked] (Kevin Hilman)
Date: Wed, 29 Oct 2014 16:57:48 -0700

Ulf Hansson <[email-masked]> writes:

> To improve error handling while adding/removing devices from their PM
> domains, we need to restructure the code a bit. Let's do this by moving
> the device specific parts into a separate function.
>
> Signed-off-by: Ulf Hansson <[email-masked]>

[...]

> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index 9d511c7..4e5fcd7 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -1358,25 +1358,81 @@ EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweron);
>  
>  #endif /* CONFIG_PM_SLEEP */
>  
> -static struct generic_pm_domain_data *__pm_genpd_alloc_dev_data(struct device *dev)
> +static int genpd_alloc_dev_data(struct generic_pm_domain *genpd,
> +				struct device *dev, struct gpd_timing_data *td)
>  {
>  	struct generic_pm_domain_data *gpd_data;
> +	int ret;
> +
> +	dev_dbg(dev, "%s()\n", __func__);
> +
> +	ret = dev_pm_get_subsys_data(dev);
> +	if (ret)
> +		return ret;
>  
>  	gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
> -	if (!gpd_data)
> -		return NULL;
> +	if (!gpd_data) {
> +		ret = -ENOMEM;
> +		goto err_alloc;
> +	}
>  
>  	mutex_init(&gpd_data->lock);
> +	gpd_data->base.dev = dev;
> +	gpd_data->td.constraint_changed = true;
> +	gpd_data->td.effective_constraint_ns = -1;
>  	gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
> +	if (td)
> +		gpd_data->td = *td;
> +
> +	spin_lock_irq(&dev->power.lock);
> +	if (!dev->power.subsys_data->domain_data)
> +		dev->power.subsys_data->domain_data = &gpd_data->base;
> +	else
> +		ret = -EINVAL;
> +	spin_unlock_irq(&dev->power.lock);
> +
> +	if (ret)
> +		goto err_data;
> +
> +	if (genpd->attach_dev)
> +		genpd->attach_dev(dev);

To me, it doesn't seem right that the attach is done in the 'alloc'
function.  IMO, the attach should stay in _add_device()

Kevin