2024-03-16 16:06:02

by Sui Jingfeng

[permalink] [raw]
Subject: [PATCH] drm/bridge: ite66121: Register HPD interrupt handler only when 'client->irq > 0'

If a specific design doesn't wire IT66121's interrupt signal output pin up
to the display controller side, then we should not register the interrupt
handler. Such a decision is valid usage, as we can fall back to polling
mode. So, don't make the assumption that a specific board always supports
HPD. Carry out a sanity check on 'client->irq' before using it, fall back
to polling mode if client->irq < 0 is true. Such a design increases the
overall flexibility.

Signed-off-by: Sui Jingfeng <[email protected]>
---
drivers/gpu/drm/bridge/ite-it66121.c | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/bridge/ite-it66121.c b/drivers/gpu/drm/bridge/ite-it66121.c
index 1c3433b5e366..052884058644 100644
--- a/drivers/gpu/drm/bridge/ite-it66121.c
+++ b/drivers/gpu/drm/bridge/ite-it66121.c
@@ -1586,13 +1586,18 @@ static int it66121_probe(struct i2c_client *client)
ctx->bridge.funcs = &it66121_bridge_funcs;
ctx->bridge.of_node = dev->of_node;
ctx->bridge.type = DRM_MODE_CONNECTOR_HDMIA;
- ctx->bridge.ops = DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID | DRM_BRIDGE_OP_HPD;
-
- ret = devm_request_threaded_irq(dev, client->irq, NULL, it66121_irq_threaded_handler,
- IRQF_ONESHOT, dev_name(dev), ctx);
- if (ret < 0) {
- dev_err(dev, "Failed to request irq %d:%d\n", client->irq, ret);
- return ret;
+ ctx->bridge.ops = DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID;
+ if (client->irq > 0) {
+ ctx->bridge.ops |= DRM_BRIDGE_OP_HPD;
+
+ ret = devm_request_threaded_irq(dev, client->irq, NULL,
+ it66121_irq_threaded_handler,
+ IRQF_ONESHOT, dev_name(dev),
+ ctx);
+ if (ret < 0) {
+ dev_err(dev, "Failed to request irq %d:%d\n", client->irq, ret);
+ return ret;
+ }
}

it66121_audio_codec_init(ctx, dev);
--
2.34.1



2024-03-16 17:43:58

by Dmitry Baryshkov

[permalink] [raw]
Subject: Re: [PATCH] drm/bridge: ite66121: Register HPD interrupt handler only when 'client->irq > 0'

On Sat, 16 Mar 2024 at 18:05, Sui Jingfeng <[email protected]> wrote:
>
> If a specific design doesn't wire IT66121's interrupt signal output pin up
> to the display controller side, then we should not register the interrupt
> handler. Such a decision is valid usage, as we can fall back to polling
> mode. So, don't make the assumption that a specific board always supports
> HPD. Carry out a sanity check on 'client->irq' before using it, fall back
> to polling mode if client->irq < 0 is true. Such a design increases the
> overall flexibility.
>
> Signed-off-by: Sui Jingfeng <[email protected]>
> ---
> drivers/gpu/drm/bridge/ite-it66121.c | 19 ++++++++++++-------
> 1 file changed, 12 insertions(+), 7 deletions(-)

Reviewed-by: Dmitry Baryshkov <[email protected]>

--
With best wishes
Dmitry

2024-03-18 15:23:10

by Neil Armstrong

[permalink] [raw]
Subject: Re: [PATCH] drm/bridge: ite66121: Register HPD interrupt handler only when 'client->irq > 0'

Hi,

On Sun, 17 Mar 2024 00:05:36 +0800, Sui Jingfeng wrote:
> If a specific design doesn't wire IT66121's interrupt signal output pin up
> to the display controller side, then we should not register the interrupt
> handler. Such a decision is valid usage, as we can fall back to polling
> mode. So, don't make the assumption that a specific board always supports
> HPD. Carry out a sanity check on 'client->irq' before using it, fall back
> to polling mode if client->irq < 0 is true. Such a design increases the
> overall flexibility.
>
> [...]

Thanks, Applied to https://gitlab.freedesktop.org/drm/misc/kernel.git (drm-misc-next)

[1/1] drm/bridge: ite66121: Register HPD interrupt handler only when 'client->irq > 0'
https://gitlab.freedesktop.org/drm/misc/kernel/-/commit/ba2d3e6709681b6c16ba8d65a23d72c706d82b5c

--
Neil