Hi Am 22.01.21 um 12:44 schrieb Noralf Trønnes:
And wrt PCI it wouldn't be a PCI connector if the card has some other connector for the display, but if it was possible to connect a display directly to the PCI connector, then yes I would call that a PCI connector.
You're not connecting a display to the computer. You're connecting an RPi and then connect the display to the RPi. The RPi acts like an external graphics card.
This begs the question: Why does the kernel provide info to userspace about the connector type? My take is that it is so the user can know which display is connected to which port on the computer.
This exactly illustrates the problem with the current naming. For a single output the distinction between bus and connector might be fuzzy. As soon as a connected SoC contains multiple connectors. The user then sees names such as card1-USB-0 and card1-USB-1, which makes no sense.
What's your opinion?Ofc as Daniel mentions it's a downside that userspace doesn't know about the connector type, and who knows when it will updated (if I don't do it). Weston will name it: "UNNAMED-%d" Mutter: "Unknown%d-%d" X: "Unknown%d-%d" Sam and Laurent has discussed adding a PANEL connector type instead of adding more connector types for panel connectors. I think that would have been a better choice instead of the SPI connector type that I added in 2019. But I think PANEL was meant for panels connected to an internal connector. Here's my protocol connector types and how it's mapped to DRM: #define GUD_CONNECTOR_TYPE_PANEL 0 #define GUD_CONNECTOR_TYPE_VGA 1 #define GUD_CONNECTOR_TYPE_COMPOSITE 2 #define GUD_CONNECTOR_TYPE_SVIDEO 3 #define GUD_CONNECTOR_TYPE_COMPONENT 4 #define GUD_CONNECTOR_TYPE_DVI 5 #define GUD_CONNECTOR_TYPE_DISPLAYPORT 6 #define GUD_CONNECTOR_TYPE_HDMI 7 static int gud_gadget_ctrl_get_connector(struct gud_gadget *gdg, unsigned int index, struct gud_connector_descriptor_req *desc) { ... gconn = &gdg->connectors[index]; switch (gconn->connector->connector_type) { case DRM_MODE_CONNECTOR_VGA: desc->connector_type = GUD_CONNECTOR_TYPE_VGA; break; case DRM_MODE_CONNECTOR_DVII: fallthrough; case DRM_MODE_CONNECTOR_DVID: fallthrough; case DRM_MODE_CONNECTOR_DVIA: desc->connector_type = GUD_CONNECTOR_TYPE_DVI; break; case DRM_MODE_CONNECTOR_Composite: desc->connector_type = GUD_CONNECTOR_TYPE_COMPOSITE; break; case DRM_MODE_CONNECTOR_SVIDEO: desc->connector_type = GUD_CONNECTOR_TYPE_SVIDEO; break; case DRM_MODE_CONNECTOR_Component: desc->connector_type = GUD_CONNECTOR_TYPE_COMPONENT; break; case DRM_MODE_CONNECTOR_DisplayPort: desc->connector_type = GUD_CONNECTOR_TYPE_DISPLAYPORT; break; case DRM_MODE_CONNECTOR_HDMIA: fallthrough; case DRM_MODE_CONNECTOR_HDMIB: desc->connector_type = GUD_CONNECTOR_TYPE_HDMI; break; default: desc->connector_type = GUD_CONNECTOR_TYPE_PANEL; break; }; int gud_connector_create(struct gud_device *gdrm, unsigned int index) { ... switch (desc.connector_type) { case GUD_CONNECTOR_TYPE_PANEL: connector_type = DRM_MODE_CONNECTOR_USB; break; case GUD_CONNECTOR_TYPE_VGA: connector_type = DRM_MODE_CONNECTOR_VGA; break; case GUD_CONNECTOR_TYPE_DVI: connector_type = DRM_MODE_CONNECTOR_DVID; break; case GUD_CONNECTOR_TYPE_COMPOSITE: connector_type = DRM_MODE_CONNECTOR_Composite; break; case GUD_CONNECTOR_TYPE_SVIDEO: connector_type = DRM_MODE_CONNECTOR_SVIDEO; break; case GUD_CONNECTOR_TYPE_COMPONENT: connector_type = DRM_MODE_CONNECTOR_Component; break; case GUD_CONNECTOR_TYPE_DISPLAYPORT: connector_type = DRM_MODE_CONNECTOR_DisplayPort; break; case GUD_CONNECTOR_TYPE_HDMI: connector_type = DRM_MODE_CONNECTOR_HDMIA; break; default: /* future types */ connector_type = DRM_MODE_CONNECTOR_USB;The more I look at it the more I think it should be 'Unknown' here.I don't understand this, how will that be better for the user?
As I said before, the display is not connected via USB. The RPi (i.e., graphics card) is. The naming would be off.
Best regards Thomas
BTW, can I try this out somehow? I do have an RPi3. Do I need a special disk image?The Pi3 doesn'have a USB device/otg connector so I haven't made an image for that one. Only the Pi Zero, model A and Pi 4 have that. The Pi2 and Pi3 have a USB hub on the soc's single USB port. Noralf.Best regards Thomasbreak; }; Noralf.Best regards Thomas-DanielBest regards ThomasBeware, new connector types have in the past resulted in userspace burning&crashing. Maybe it's become better ... Acked-by: Daniel Vetter <daniel.vetter@xxxxxxxx>/** * struct drm_mode_get_connector - Get connector metadata. -- 2.23.0 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel-- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Felix Imendörffer_______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel_______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
-- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Felix Imendörffer
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