<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"> <head>  <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <style type="text/css">P.ImprintUniqueID { MARGIN: 0cm 0cm 0pt } LI.ImprintUniqueID { MARGIN: 0cm 0cm 0pt } DIV.ImprintUniqueID { MARGIN: 0cm 0cm 0pt } TABLE.ImprintUniqueIDTable { MARGIN: 0cm 0cm 0pt } DIV.Section1 { page: Section1 } </style> <meta name="Generator" content="Microsoft Word 15 (filtered medium)"> <style></style> </head> <body lang="DE" link="#467886" vlink="#96607D" style="word-wrap:break-word"> <div class="WordSection1"> Hi,<o:p></o:p> <o:p> </o:p> <o:p> </o:p> I’m pretty new to DRM/DRI and wonder if there is a way to have a stable identification of connectors across changes in the Linux kernel and/or in the devicetree?<o:p></o:p> <o:p> </o:p> Our hardware contains an iMX8QM with two displays, each one connected to a MIPI-DSI channel. We use kernel 6.1.38.<o:p></o:p> In the output of “modetest -c” the connectors are called LVDS-1 and LVDS-2. These names are built in modetest.c from connector_type and connector_type_id.<o:p></o:p> <o:p> </o:p> connector_type_id is set in the kernel in drivers/gpu/drm/drm_connector.c in __drm_connector_init():<o:p></o:p> <o:p> </o:p> <pre> <a href="https://elixir.bootlin.com/linux/latest/C/ident/connector">connector</a>-><a href="https://elixir.bootlin.com/linux/latest/C/ident/connector_type_id">connector_type_id</a> =<o:p></o:p></pre> <pre> <a href="https://elixir.bootlin.com/linux/latest/C/ident/ida_alloc_min">ida_alloc_min</a>(<a href="https://elixir.bootlin.com/linux/latest/C/ident/connector_ida">connector_ida</a>, 1, <a href="https://elixir.bootlin.com/linux/latest/C/ident/GFP_KERNEL">GFP_KERNEL</a>);<o:p></o:p></pre> <o:p> </o:p> Seems to me that this number depends on initialization order only. Is there any other way to identify a connector?<o:p></o:p> <o:p> </o:p> If not, will the type_id be stable as long as we don’t change the kernel version and the device tree?<o:p></o:p> <o:p> </o:p> <o:p> </o:p> Best Regards,<o:p></o:p> Joerg Albert<o:p></o:p> <o:p> </o:p> <o:p> </o:p> <o:p> </o:p> <o:p> </o:p> <o:p> </o:p> +491747384960<o:p></o:p> <o:p> </o:p> <o:p> </o:p> </div> We move the world for the better through technology and engineering. <a href="https://www.iav.com" title="" target="" style="font-family:Arial;font-size:8pt;color:#0563C1;">www.iav.com</a> | <a href="https://www.facebook.com/insideiav" title="" target="" style="font-family:Arial;font-size:8pt;color:#0563C1;">Facebook</a> | <a href="https://www.instagram.com/inside_iav/" title="" target="" style="font-family:Arial;font-size:8pt;color:#0563C1;">Instagram</a> | <a href="https://www.linkedin.com/company/iav-gmbh" title="" target="" style="font-family:Arial;font-size:8pt;color:#0563C1;">LinkedIn</a> | <a href="https://www.xing.com/companies/iav" title="" target="" style="font-family:Arial;font-size:8pt;color:#0563C1;">Xing</a> | <a href="https://www.youtube.com/user/IAVchannel" title="" target="" style="font-family:Arial;font-size:8pt;color:#0563C1;">YouTube</a> IAV GmbH Ingenieurgesellschaft Auto und Verkehr; Sitz/Registered Office: Berlin; Registergericht/Registration Court: Amtsgericht Charlottenburg (Berlin); Registernummer/Company Registration Number: HRB 21 280 B; Geschäftsführer/Managing Directors: Joerg Astalosch, Martin Mahlke, Dr. Uwe Horn; Vorsitzender des Aufsichtsrates/Chairman of the Supervisory Board: Dr. Nikolai Ardey <a href="https://www.iav.com/datenschutz" title="" target="" style="color:#0563C1;">Datenschutzhinweise/Privacy Policy</a> </body> </html>