topic Implementing Dual-Function GPIO Key Mapping for Display Control and System Restart on i.MX8QXP SoM in i.MX Processors https://community.nxp.com/t5/i-MX-Processors/Implementing-Dual-Function-GPIO-Key-Mapping-for-Display-Control/m-p/2140650#M239588 <P>Hi,<BR /><BR />We are using an <STRONG>i.MX8QXP SoM</STRONG> and have built the OS image with the following Yocto configuration:</P><UL><LI><P>MACHINE = imx8qxpc0mek</P></LI><LI><P>DISTRO = fsl-imx-wayland</P></LI><LI><P>DISTRO_VERSION = 6.6-scarthgap</P></LI><LI><P><STRONG>Kernel Version</STRONG>: 6.6.36</P></LI></UL><P>A <STRONG>GPIO expander is connected over I2C</STRONG>, and we have successfully mapped several GPIOs to key events like number keys and letters.</P><P>Now, we want to assign a <STRONG>dual-functionality to one GPIO key</STRONG>:</P><UL><LI><P><STRONG>Short press</STRONG>: Turns <STRONG>off the display</STRONG>.</P></LI><LI><P><STRONG>Long press (≥5 seconds)</STRONG>: <STRONG>Restarts the system</STRONG>.</P></LI></UL><P>We are looking for the appropriate <STRONG>Linux input event keycode</STRONG> to assign this behavior with dual functionality and device tree configuration.<BR /><BR />Regads,<BR />Adnan</P> Fri, 25 Jul 2025 06:52:31 GMT adnan_dst 2025-07-25T06:52:31Z Implementing Dual-Function GPIO Key Mapping for Display Control and System Restart on i.MX8QXP SoM https://community.nxp.com/t5/i-MX-Processors/Implementing-Dual-Function-GPIO-Key-Mapping-for-Display-Control/m-p/2140650#M239588 <P>Hi,<BR /><BR />We are using an <STRONG>i.MX8QXP SoM</STRONG> and have built the OS image with the following Yocto configuration:</P><UL><LI><P>MACHINE = imx8qxpc0mek</P></LI><LI><P>DISTRO = fsl-imx-wayland</P></LI><LI><P>DISTRO_VERSION = 6.6-scarthgap</P></LI><LI><P><STRONG>Kernel Version</STRONG>: 6.6.36</P></LI></UL><P>A <STRONG>GPIO expander is connected over I2C</STRONG>, and we have successfully mapped several GPIOs to key events like number keys and letters.</P><P>Now, we want to assign a <STRONG>dual-functionality to one GPIO key</STRONG>:</P><UL><LI><P><STRONG>Short press</STRONG>: Turns <STRONG>off the display</STRONG>.</P></LI><LI><P><STRONG>Long press (≥5 seconds)</STRONG>: <STRONG>Restarts the system</STRONG>.</P></LI></UL><P>We are looking for the appropriate <STRONG>Linux input event keycode</STRONG> to assign this behavior with dual functionality and device tree configuration.<BR /><BR />Regads,<BR />Adnan</P> Fri, 25 Jul 2025 06:52:31 GMT https://community.nxp.com/t5/i-MX-Processors/Implementing-Dual-Function-GPIO-Key-Mapping-for-Display-Control/m-p/2140650#M239588 adnan_dst 2025-07-25T06:52:31Z