Re: [PATCH] of: irq: Add a helper function for irq_of_parse_and_map

Re: [PATCH] of: irq: Add a helper function for irq_of_parse_and_map

[Rob Herring]

On Sat, Jul 21, 2018 at 9:38 AM Liu Xiang <liu.xiang6@zte.com.cn> wrote:
>
> Implement a resource managed irq_of_parse_and_map function.

That is obvious from the diff. Why do you need this?

Anything that is a platform device should use platform_get_irq. The
mapping is created by the core Also, of_irq_get() is preferred over
irq_of_parse_and_map() for new users as it has better error return
handling.

>
> Signed-off-by: Liu Xiang <liu.xiang6@zte.com.cn>
> ---
>  drivers/of/irq.c       | 38 ++++++++++++++++++++++++++++++++++++++
>  include/linux/of_irq.h |  7 +++++++
>  2 files changed, 45 insertions(+)
>
> diff --git a/drivers/of/irq.c b/drivers/of/irq.c
> index 02ad93a..947fe41 100644
> --- a/drivers/of/irq.c
> +++ b/drivers/of/irq.c
> @@ -45,6 +45,44 @@ unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
>  }
>  EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
>
> +static void devm_irq_dispose_mapping(struct device *dev, void *res)
> +{
> +       irq_dispose_mapping(*(unsigned int *)res);

We don't ref count creating mappings, so this would break for any shared irq.

Rob

Re:Re: [PATCH] of: irq: Add a helper function for irq_of_parse_and_map

[liuxiang]

I found in probe function some drivers use irq_of_parse_and_map
and do not call irq_dispose_mapping in err path, while other drivers do.
So I think a resource managed irq_of_parse_and_map function can 
be better to finish this job.

At 2018-07-23 23:28:52, "Rob Herring" <robh+dt@kernel.org> wrote:
>On Sat, Jul 21, 2018 at 9:38 AM Liu Xiang <liu.xiang6@zte.com.cn> wrote:
>>
>> Implement a resource managed irq_of_parse_and_map function.
>
>That is obvious from the diff. Why do you need this?
>
>Anything that is a platform device should use platform_get_irq. The
>mapping is created by the core Also, of_irq_get() is preferred over
>irq_of_parse_and_map() for new users as it has better error return
>handling.
>
>>
>> Signed-off-by: Liu Xiang <liu.xiang6@zte.com.cn>
>> ---
>>  drivers/of/irq.c       | 38 ++++++++++++++++++++++++++++++++++++++
>>  include/linux/of_irq.h |  7 +++++++
>>  2 files changed, 45 insertions(+)
>>
>> diff --git a/drivers/of/irq.c b/drivers/of/irq.c
>> index 02ad93a..947fe41 100644
>> --- a/drivers/of/irq.c
>> +++ b/drivers/of/irq.c
>> @@ -45,6 +45,44 @@ unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
>>  }
>>  EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
>>
>> +static void devm_irq_dispose_mapping(struct device *dev, void *res)
>> +{
>> +       irq_dispose_mapping(*(unsigned int *)res);
>
>We don't ref count creating mappings, so this would break for any shared irq.
>
>Rob