Re: [PATCH v5 00/18] Add HPD support for Rockchip Analogix DP

[Damon Ding]

Hi Marek,

On 10/29/2026 4:29 PM, Marek Szyprowski wrote:
> On 27.10.2026 14:27, Damon Ding wrote:
> > This series improves the HPD (Hotplug Detect) interrupt handling in
> > the Analogix DP driver to enable reliable native HPD pin detection on
> > Rockchip platforms, and introduces platform-specific HPD detection
> > schemes with fine-grained interrupt control.
> >
> > On Rockchip platforms, the Analogix DP native HPD pin IRQ requires the
> > DP controller to remain powered, clocked and initialized to generate
> > plug/unplug interrupts. The previous driver enabled/disabled IRQ during
> > bridge enable/disable, which left no HPD detection when the display
> > pipeline was inactive. Additionally, the interrupt mute/unmute/clear
> > routines operated on all HPD interrupt bits unconditionally, lacking
> > the granularity needed for per-event control.
> >
> > The series reorganizes IRQ and pm_runtime management into bind/unbind,
> > adds IRQF_ONESHOT to eliminate read-modify-write races on interrupt
> > mask registers between hardirq and threaded handlers, converts the
> > interrupt type detection to a bitmask-based scheme for fine-grained
> > mute/unmute/clear operations, and configures Rockchip platforms to use
> > the HOTPLUG_CHG interrupt with a 2ms HPD deglitch setting for better
> > stability.
> >
> > Furthermore, the next bridge is now resolved into bridge->next_bridge
> > instead of the platform data field, the forced connected-status logic
> > is restricted to panel endpoints based on the bridge chain, and HPD
> > events from downstream bridges (e.g. display-connector with hpd-gpios)
> > are handled through the .hpd_notify callback.
> >
> > Tested on RK3576 with both native HPD pin and GPIO HPD configurations.
> >
> > Native HPD pin mode:
> >
> >    &edp {
> >        status = "okay";
> >        pinctrl-names = "default";
> >        pinctrl-0 = <&edp_txm0_pins>;
> >    };
> >
> > GPIO HPD mode:
> >
> >    &edp {
> >        status = "okay";
> >        pinctrl-names = "default";
> >        pinctrl-0 = <&edp0_hpd>;
> >        hpd-gpios = <&gpio4 RK_PC1 GPIO_ACTIVE_HIGH>;
> >    };
> >
> >    &pinctrl {
> >        edp {
> >            edp0_hpd: edp0-hpd {
> >                rockchip,pins = <4 RK_PC1 0 &pcfg_pull_none>;
> >            };
> >        };
> >    };
> >
> > Display-connector mode (DP connector without HPD GPIO):
> >
> >    &edp_out_conn {
> >        remote-endpoint = <&dp_con_in>;
> >    };
> >
> >    dp-con {
> >        compatible = "dp-connector";
> >        label = "DP OUT";
> >        type = "full-size";
> >
> >        port {
> >            dp_con_in: endpoint {
> >                remote-endpoint = <&edp_out_conn>;
> >            };
> >        };
> >    };
> >
> > Display-connector mode (DP connector with HPD GPIO):
> >
> >    dp-con {
> >        compatible = "dp-connector";
> >        label = "DP OUT";
> >        type = "full-size";
> >        pinctrl-0 = <&edp0_hpd>;
> >        pinctrl-names = "default";
> >        hpd-gpios = <&gpio4 RK_PC1 GPIO_ACTIVE_HIGH>;
> >
> >        port {
> >            dp_con_in: endpoint {
> >                remote-endpoint = <&edp_out_conn>;
> >            };
> >        };
> >    };
> >
> > All four configurations detect cable plug/unplug events correctly.
>
> Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
>
> Snow, Peach-Pit and Peach-Pi Chromebooks still work fine with this patchset.

Thanks for your testing and confirmation.

Best regards,
Damon