From: treding@nvidia•com (Thierry Reding)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH v4 14/16] drm: bridge: analogix/dp: try force hpd after plug in lookup failed
Date: Mon, 7 Sep 2015 10:20:18 +0200 [thread overview]
Message-ID: <20150907082017.GB19961@ulmo.nvidia.com> (raw)
In-Reply-To: <55EBBA0C.1030100@rock-chips.com>
On Sun, Sep 06, 2015 at 11:59:08AM +0800, Yakir Yang wrote:
> Hi Thierry,
>
> ? 09/03/2015 05:04 PM, Thierry Reding ??:
> >On Thu, Sep 03, 2015 at 12:27:47PM +0800, Yakir Yang wrote:
> >>Hi Rob,
> >>
> >>? 09/03/2015 04:17 AM, Rob Herring ??:
> >>>On Tue, Sep 1, 2015 at 1:14 AM, Yakir Yang <ykk@rock-chips•com> wrote:
> >>>>Some edp screen do not have hpd signal, so we can't just return
> >>>>failed when hpd plug in detect failed.
> >>>This is a property of the panel (or connector perhaps), so this
> >>>property should be located there. At least, it is a common issue and
> >>>not specific to this chip. We could have an HDMI connector and failed
> >>>to hook up HPD for example. A connector node is also where hpd-gpios
> >>>should be located instead (and are already defined by
> >>>../bindings/video/hdmi-connector.txt). Perhaps we need a eDP connector
> >>>binding, too.
> >>Yep, I agree with your front point, it is a property of panel, not specific
> >>to eDP controller, so this code should handle in connector logic.
> > From your description it sounds more like this is in fact a property of
> >the panel. Or maybe I should say "quirk". If the panel doesn't generate
> >the HPD signal, then that should be a property of the panel, not the
> >connector. The eDP specification mandates that connectors have a HPD
> >signal, though it allows the "HPD conductor in the connector cable" to
> >be omitted if not used by the source. I'd consider the cable to belong
> >to the panel rather than the connector, so absence of HPD, either
> >because the cable doesn't have the conductor or because the panel does
> >not generate the signal, should be a quirk of the panel.
> >
> >That said you could have a panel that supports HPD connected via a cable
> >that doesn't transmit it, so this would be a per-board variant and hence
> >should be a device tree property rather than hard-coded in some panel
> >driver.
> >
> >Conversely, if the panel isn't capable of generating an HPD signal, then
> >I don't think it would be appropriate to make it a DT property. It would
> >be better to hard-code it in the driver, lest someone forget to set the
> >property in DT and get stuck with a device that isn't operational.
>
> Oh, you're right, if it's a cable quirk, then DT property would be okay, if
> it
> is a problem of panel, then maybe hard-code in driver would be better.
>
> After look up for the document of panel "innolux,n116bge", I haven't see
> any description of hot plug signal, and even not found in PIN ASSIGNMENT.
> So I believe it's a panel problem, that's to say it should handle in panel
> driver.
The datasheet that I have for that panel lists HPD as pin 17. Also I
used to have a setup with that panel and I distinctly remember hotplug
working just fine. Perhaps this is an issue with a specific variant of
the panel? Or perhaps this is indeed a problem with the cable that's
connecting the panel to the board. It could be one of those cases where
they left out the HPD conductor to save money.
Thierry
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next prev parent reply other threads:[~2015-09-07 8:20 UTC|newest]
Thread overview: 133+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-09-01 5:46 [PATCH v4 0/16] Add Analogix Core Display Port Driver Yakir Yang
2015-09-01 5:46 ` [PATCH v4 01/16] drm: exynos/dp: fix code style Yakir Yang
2015-09-03 0:21 ` Krzysztof Kozlowski
2015-09-03 5:04 ` Yakir Yang
2015-09-03 5:08 ` Krzysztof Kozlowski
2015-09-03 5:33 ` Yakir Yang
2015-09-03 5:57 ` Joe Perches
2015-09-06 1:33 ` Yakir Yang
2015-09-01 5:49 ` [PATCH v4 02/16] drm: exynos/dp: convert to drm bridge mode Yakir Yang
2015-09-01 5:52 ` [PATCH v4 04/16] drm: bridge: analogix/dp: remove duplicate configuration of link rate and link count Yakir Yang
2015-09-01 5:55 ` [PATCH v4 05/16] drm: bridge: analogix/dp: dynamic parse sync_pol & interlace & colorimetry Yakir Yang
2015-09-03 8:04 ` Krzysztof Kozlowski
2015-09-06 2:00 ` Yakir Yang
2015-09-01 5:58 ` [PATCH v4 06/16] Documentation: drm/bridge: add document for analogix_dp Yakir Yang
2015-09-01 6:01 ` [PATCH v4 07/16] ARM: dts: exynos/dp: remove some properties that deprecated by analogix_dp driver Yakir Yang
2015-09-03 0:01 ` Krzysztof Kozlowski
2015-09-01 6:01 ` [PATCH v4 08/16] drm: rockchip/dp: add rockchip platform dp driver Yakir Yang
2015-09-01 14:24 ` Heiko Stuebner
2015-09-01 21:00 ` Heiko Stuebner
2015-09-01 6:01 ` [PATCH v4 09/16] drm: rockchip: add bpc and color mode setting Yakir Yang
2015-09-01 21:00 ` Heiko Stuebner
2015-09-01 6:04 ` [PATCH v4 10/16] phy: Add driver for rockchip Display Port PHY Yakir Yang
2015-09-01 16:51 ` Heiko Stuebner
2015-09-01 20:58 ` Heiko Stuebner
2015-09-02 13:27 ` Rob Herring
2015-09-03 3:25 ` Yakir Yang
2015-09-03 13:52 ` Heiko Stuebner
2015-09-06 4:09 ` Yakir Yang
2015-09-01 6:07 ` [PATCH v4 11/16] drm: bridge: analogix/dp: add platform device type support Yakir Yang
2015-09-04 0:36 ` Krzysztof Kozlowski
2015-09-06 4:07 ` Yakir Yang
2015-09-06 23:55 ` Krzysztof Kozlowski
2015-09-01 6:09 ` [PATCH v4 12/16] drm: bridge: analogix/dp: add some rk3288 special registers setting Yakir Yang
2015-09-01 6:11 ` [PATCH v4 13/16] drm: bridge: analogix/dp: add max link rate and lane count limit for RK3288 Yakir Yang
2015-09-01 6:14 ` [PATCH v4 14/16] drm: bridge: analogix/dp: try force hpd after plug in lookup failed Yakir Yang
2015-09-02 20:17 ` Rob Herring
2015-09-03 4:27 ` Yakir Yang
2015-09-03 9:04 ` Thierry Reding
2015-09-04 10:20 ` Russell King - ARM Linux
2015-09-07 9:01 ` Thierry Reding
[not found] ` <55EBBA0C.1030100@rock-chips.com>
2015-09-07 8:20 ` Thierry Reding [this message]
2015-09-04 21:46 ` Rob Herring
2015-09-06 8:20 ` Yakir Yang
2015-09-07 8:39 ` Thierry Reding
2015-09-03 8:47 ` Thierry Reding
2015-09-03 21:55 ` Rob Herring
2015-09-04 10:01 ` Thierry Reding
2015-09-01 6:17 ` [PATCH v4 15/16] drm: bridge: analogix/dp: move hpd detect to connector detect function Yakir Yang
2015-09-01 6:20 ` [PATCH v4 16/16] drm: bridge: analogix/dp: add edid modes parse in get_modes method Yakir Yang
[not found] ` <1441086598-24995-1-git-send-email-ykk@rock-chips.com>
2015-09-01 20:46 ` [PATCH v4 03/16] drm: bridge: analogix/dp: split exynos dp driver to bridge dir Heiko Stuebner
2015-09-04 21:06 ` Rob Herring
2015-09-04 21:29 ` Heiko Stuebner
2015-09-07 8:11 ` Thierry Reding
2015-09-02 14:50 ` Emil Velikov
2015-09-03 3:55 ` Yakir Yang
2015-09-03 0:58 ` Krzysztof Kozlowski
2015-09-03 5:30 ` Yakir Yang
2015-09-04 0:41 ` Krzysztof Kozlowski
2015-09-06 7:49 ` Yakir Yang
2015-09-07 0:22 ` Krzysztof Kozlowski
2015-09-01 21:47 ` [PATCH v4 0/16] Add Analogix Core Display Port Driver Heiko Stuebner
2015-09-22 7:20 ` [PATCH v5 0/17] " Yakir Yang
2015-09-22 7:26 ` [PATCH v5 01/17] drm: exynos: dp: convert to drm bridge mode Yakir Yang
2015-09-22 7:34 ` [PATCH v5 03/17] drm: bridge: analogix/dp: fix some obvious code style Yakir Yang
2015-09-30 5:22 ` Krzysztof Kozlowski
2015-09-30 6:52 ` Yakir Yang
2015-09-22 7:35 ` [PATCH v5 04/17] drm: bridge: analogix/dp: remove duplicate configuration of link rate and link count Yakir Yang
2015-09-22 7:37 ` [PATCH v5 05/17] drm: bridge: analogix/dp: dynamic parse sync_pol & interlace & dynamic_range Yakir Yang
2015-09-30 5:32 ` Krzysztof Kozlowski
[not found] ` <560B8CF1.7050102@rock-chips.com>
2015-09-30 7:34 ` Krzysztof Kozlowski
[not found] ` <560B9B33.2060409@rock-chips.com>
2015-09-30 8:26 ` Krzysztof Kozlowski
2015-09-30 9:39 ` Yakir Yang
2015-09-22 7:40 ` [PATCH v5 06/17] Documentation: drm/bridge: add document for analogix_dp Yakir Yang
2015-09-22 7:43 ` [PATCH v5 07/17] ARM: dts: exynos/dp: remove some properties that deprecated by analogix_dp driver Yakir Yang
2015-09-30 5:39 ` Krzysztof Kozlowski
2015-09-30 7:20 ` Yakir Yang
2015-09-22 7:45 ` [PATCH v5 08/17] drm: rockchip: dp: add rockchip platform dp driver Yakir Yang
2015-09-22 7:48 ` [PATCH v5 09/17] Documentation: drm/bridge: add document for analogix_dp Yakir Yang
2015-09-22 7:48 ` [PATCH v5 10/17] phy: Add driver for rockchip Display Port PHY Yakir Yang
2015-09-22 7:51 ` [PATCH v5 11/17] Documentation: phy: add document for rockchip dp phy Yakir Yang
2015-09-22 7:55 ` [PATCH v5 12/17] drm: rockchip: vop: add bpc and color mode setting Yakir Yang
2015-09-22 7:57 ` [PATCH v5 13/17] drm: bridge: analogix/dp: add some rk3288 special registers setting Yakir Yang
2015-09-22 8:00 ` [PATCH v5 14/17] drm: bridge: analogix/dp: add max link rate and lane count limit for RK3288 Yakir Yang
2015-09-22 8:02 ` [PATCH v5 15/17] drm: bridge: analogix/dp: try force hpd after plug in lookup failed Yakir Yang
2015-09-22 8:05 ` [PATCH v5 16/17] drm: bridge: analogix/dp: move hpd detect to connector detect function Yakir Yang
2015-09-22 8:07 ` [PATCH v5 17/17] drm: bridge: analogix/dp: add edid modes parse in get_modes method Yakir Yang
[not found] ` <1442906963-2883-1-git-send-email-ykk@rock-chips.com>
2015-09-30 5:17 ` [PATCH v5 02/17] drm: bridge: analogix/dp: split exynos dp driver to bridge directory Krzysztof Kozlowski
2015-09-30 6:48 ` Yakir Yang
2015-10-07 6:25 ` [PATCH v5 0/17] Add Analogix Core Display Port Driver Yakir Yang
2015-10-07 8:46 ` Javier Martinez Canillas
2015-10-07 9:02 ` Yakir Yang
2015-10-07 9:26 ` Javier Martinez Canillas
[not found] ` <5614FC6B.4080702@rock-chips.com>
2015-10-07 11:25 ` Javier Martinez Canillas
2015-10-08 0:40 ` Yakir Yang
2015-10-10 14:31 ` Yakir Yang
2015-10-13 9:21 ` Javier Martinez Canillas
2015-10-13 13:50 ` Yakir Yang
2015-10-14 8:18 ` Javier Martinez Canillas
2015-10-10 15:35 ` [PATCH v6 " Yakir Yang
2015-10-10 15:38 ` [PATCH v6 01/17] drm: exynos: dp: convert to drm bridge mode Yakir Yang
2015-10-10 15:41 ` [PATCH v6 03/17] drm: bridge: analogix/dp: fix some obvious code style Yakir Yang
2015-10-10 15:43 ` [PATCH v6 04/17] drm: bridge: analogix/dp: remove duplicate configuration of link rate and link count Yakir Yang
2015-10-10 15:46 ` [PATCH v6 05/17] drm: bridge: analogix/dp: dynamic parse sync_pol & interlace & dynamic_range Yakir Yang
2015-10-12 0:37 ` Yakir Yang
2015-10-12 0:49 ` Krzysztof Kozlowski
2015-10-12 2:43 ` Yakir Yang
2015-10-12 3:51 ` Krzysztof Kozlowski
2015-10-12 4:09 ` Yakir Yang
2015-10-12 4:16 ` Krzysztof Kozlowski
2015-10-10 15:49 ` [PATCH v6 06/17] Documentation: drm/bridge: add document for analogix_dp Yakir Yang
2015-10-10 15:49 ` [PATCH v6 07/17] ARM: dts: exynos/dp: remove some properties that deprecated by analogix_dp driver Yakir Yang
2015-10-10 15:51 ` [PATCH v6 08/17] drm: rockchip: dp: add rockchip platform dp driver Yakir Yang
2015-10-10 15:53 ` [PATCH v6 09/17] Documentation: drm/bridge: add document for analogix_dp Yakir Yang
2015-10-10 15:55 ` [PATCH v6 10/17] phy: Add driver for rockchip Display Port PHY Yakir Yang
2015-10-12 15:02 ` Kishon Vijay Abraham I
2015-10-12 16:18 ` Heiko Stübner
2015-10-13 1:20 ` Yakir Yang
2015-10-10 15:58 ` [PATCH v6 11/17] Documentation: phy: add document for rockchip dp phy Yakir Yang
2015-10-12 22:28 ` Kishon Vijay Abraham I
2015-10-13 1:21 ` Yakir Yang
2015-10-10 16:00 ` [PATCH v6 12/17] drm: rockchip: vop: add bpc and color mode setting Yakir Yang
2015-10-10 16:05 ` [PATCH v6 13/17] drm: bridge: analogix/dp: add some rk3288 special registers setting Yakir Yang
2015-10-10 16:05 ` [PATCH v6 14/17] drm: bridge: analogix/dp: add max link rate and lane count limit for RK3288 Yakir Yang
2015-10-10 16:05 ` [PATCH v6 15/17] drm: bridge: analogix/dp: try force hpd after plug in lookup failed Yakir Yang
2015-10-10 16:05 ` [PATCH v6 16/17] drm: bridge: analogix/dp: move hpd detect to connector detect function Yakir Yang
2015-10-10 16:06 ` [PATCH v6 17/17] drm: bridge: analogix/dp: add edid modes parse in get_modes method Yakir Yang
2015-10-12 4:29 ` [PATCH v7 05/17] drm: bridge: analogix/dp: dynamic parse sync_pol & interlace & dynamic_range Yakir Yang
2015-10-12 6:54 ` Krzysztof Kozlowski
2015-10-12 7:20 ` Yakir Yang
2015-10-19 10:40 ` [PATCH v6 0/17] Add Analogix Core Display Port Driver Javier Martinez Canillas
2015-10-20 2:10 ` Yakir Yang
2015-10-20 9:48 ` Javier Martinez Canillas
2015-10-20 11:40 ` Yakir Yang
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