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

From: Srinivas Kandagatla
Date: Thu Mar 10 2022 - 05:43:05 EST




On 10/03/2022 10:23, Lad, Prabhakar wrote:
On Thu, Mar 10, 2022 at 10:16 AM Srinivas Kandagatla
<srinivas.kandagatla@xxxxxxxxxx> 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@xxxxxxxxxxxxxx/


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@xxxxxxxxxxxxxx>
---
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@xxxxxxxxxxxxxx/

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");