Re: [PATCH v2 1/4] soc: qcom: ice: introduce devm_of_qcom_ice_get

[Abel Vesa <abel.vesa@linaro.org>]

On 25-01-17 14:18:50, Tudor Ambarus wrote:
> Callers of of_qcom_ice_get() leak the device reference taken by
> of_find_device_by_node(). Introduce devm variant for of_qcom_ice_get().
> Existing consumers need the ICE instance for the entire life of their
> device, thus exporting qcom_ice_put() is not required.
> 
> Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>

Good catch. LGTM.

Reviewed-by: Abel Vesa <abel.vesa@linaro.org>

> ---
>  drivers/soc/qcom/ice.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
>  include/soc/qcom/ice.h |  2 ++
>  2 files changed, 50 insertions(+)
> 
> diff --git a/drivers/soc/qcom/ice.c b/drivers/soc/qcom/ice.c
> index 393d2d1d275f..79e04bff3e33 100644
> --- a/drivers/soc/qcom/ice.c
> +++ b/drivers/soc/qcom/ice.c
> @@ -11,6 +11,7 @@
>  #include <linux/cleanup.h>
>  #include <linux/clk.h>
>  #include <linux/delay.h>
> +#include <linux/device.h>
>  #include <linux/iopoll.h>
>  #include <linux/of.h>
>  #include <linux/of_platform.h>
> @@ -324,6 +325,53 @@ struct qcom_ice *of_qcom_ice_get(struct device *dev)
>  }
>  EXPORT_SYMBOL_GPL(of_qcom_ice_get);
>  
> +static void qcom_ice_put(const struct qcom_ice *ice)
> +{
> +	struct platform_device *pdev = to_platform_device(ice->dev);
> +
> +	if (!platform_get_resource_byname(pdev, IORESOURCE_MEM, "ice"))
> +		platform_device_put(pdev);
> +}
> +
> +static void devm_of_qcom_ice_put(struct device *dev, void *res)
> +{
> +	qcom_ice_put(*(struct qcom_ice **)res);
> +}
> +
> +/**
> + * devm_of_qcom_ice_get() - Devres managed helper to get an ICE instance from
> + * a DT node.
> + * @dev: device pointer for the consumer device.
> + *
> + * This function will provide an ICE instance either by creating one for the
> + * consumer device if its DT node provides the 'ice' reg range and the 'ice'
> + * clock (for legacy DT style). On the other hand, if consumer provides a
> + * phandle via 'qcom,ice' property to an ICE DT, the ICE instance will already
> + * be created and so this function will return that instead.
> + *
> + * Return: ICE pointer on success, NULL if there is no ICE data provided by the
> + * consumer or ERR_PTR() on error.
> + */
> +struct qcom_ice *devm_of_qcom_ice_get(struct device *dev)
> +{
> +	struct qcom_ice *ice, **dr;
> +
> +	dr = devres_alloc(devm_of_qcom_ice_put, sizeof(*dr), GFP_KERNEL);
> +	if (!dr)
> +		return ERR_PTR(-ENOMEM);
> +
> +	ice = of_qcom_ice_get(dev);
> +	if (!IS_ERR_OR_NULL(ice)) {
> +		*dr = ice;
> +		devres_add(dev, dr);
> +	} else {
> +		devres_free(dr);
> +	}
> +
> +	return ice;
> +}
> +EXPORT_SYMBOL_GPL(devm_of_qcom_ice_get);
> +
>  static int qcom_ice_probe(struct platform_device *pdev)
>  {
>  	struct qcom_ice *engine;
> diff --git a/include/soc/qcom/ice.h b/include/soc/qcom/ice.h
> index 5870a94599a2..d5f6a228df65 100644
> --- a/include/soc/qcom/ice.h
> +++ b/include/soc/qcom/ice.h
> @@ -34,4 +34,6 @@ int qcom_ice_program_key(struct qcom_ice *ice,
>  			 int slot);
>  int qcom_ice_evict_key(struct qcom_ice *ice, int slot);
>  struct qcom_ice *of_qcom_ice_get(struct device *dev);
> +struct qcom_ice *devm_of_qcom_ice_get(struct device *dev);
> +
>  #endif /* __QCOM_ICE_H__ */
> 
> -- 
> 2.48.0.rc2.279.g1de40edade-goog
>