Re: [PATCH] slimbus: qcom-ngd-ctrl: Use platform_get_irq() to get the interrupt

[Srinivas Kandagatla <srinivas.kandagatla@linaro.org>]

On 10/03/2022 10:23, Lad, Prabhakar wrote:
> On Thu, Mar 10, 2022 at 10:16 AM Srinivas Kandagatla
> <srinivas.kandagatla@linaro.org> wrote:
>>
>>
>>
>> On 24/12/2021 16:13, Lad Prabhakar wrote:
>>> platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
>>> allocation of IRQ resources in DT core code, this causes an issue
>>
>> Are you saying that we should not be using platform_get_resource(pdev,
>> IORESOURCE_IRQ, ...) on drivers that support DT?
>>
>>> when using hierarchical interrupt domains using "interrupts" property
>>> in the node as this bypasses the hierarchical setup and messes up the
>>> irq chaining.
>>
>> Should this not be fixed in the DT core itself?
>>
> Yes the plan is to fix in the DT core itself (refer [0]).
> 
> [0] https://patchwork.kernel.org/project/linux-renesas-soc/patch/20211209001056.29774-1-prabhakar.mahadev-lad.rj@bp.renesas.com/
> 
>>>
>>> In preparation for removal of static setup of IRQ resource from DT core
>>> code use platform_get_irq().
>>
>> I would prefer this patch to be part of the series that removes IRQ
>> resource handling from DT core.
>>
> Since there are too many users (which are in different subsystems)
> getting this all in single series would be a pain. As a result it is
> split up into individual subsystems.
Am happy for this to be included in that series,
TBH, this patch make more sense along with that series than by itself.

This would also give better insight of what exactly is changing in 
platform_get_resource() w.r.t handling IRQ resources.


--srini

> 
> Cheers,
> Prabhakar
> 
>>
>> --srini
>>
>>>
>>> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>>> ---
>>> Hi,
>>>
>>> Dropping usage of platform_get_resource() was agreed based on
>>> the discussion [0].
>>>
>>> [0] https://patchwork.kernel.org/project/linux-renesas-soc/
>>> patch/20211209001056.29774-1-prabhakar.mahadev-lad.rj@bp.renesas.com/
>>>
>>> Cheers,
>>> Prabhakar
>>> ---
>>>    drivers/slimbus/qcom-ngd-ctrl.c | 10 ++++------
>>>    1 file changed, 4 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/drivers/slimbus/qcom-ngd-ctrl.c b/drivers/slimbus/qcom-ngd-ctrl.c
>>> index 7040293c2ee8..0f29a08b4c09 100644
>>> --- a/drivers/slimbus/qcom-ngd-ctrl.c
>>> +++ b/drivers/slimbus/qcom-ngd-ctrl.c
>>> @@ -1526,13 +1526,11 @@ static int qcom_slim_ngd_ctrl_probe(struct platform_device *pdev)
>>>        if (IS_ERR(ctrl->base))
>>>                return PTR_ERR(ctrl->base);
>>>
>>> -     res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
>>> -     if (!res) {
>>> -             dev_err(&pdev->dev, "no slimbus IRQ resource\n");
>>> -             return -ENODEV;
>>> -     }
>>> +     ret = platform_get_irq(pdev, 0);
>>> +     if (ret < 0)
>>> +             return ret;
>>>
>>> -     ret = devm_request_irq(dev, res->start, qcom_slim_ngd_interrupt,
>>> +     ret = devm_request_irq(dev, ret, qcom_slim_ngd_interrupt,
>>>                               IRQF_TRIGGER_HIGH, "slim-ngd", ctrl);
>>>        if (ret) {
>>>                dev_err(&pdev->dev, "request IRQ failed\n");