Add documentation for led matrix

[qmk_firmware.git] / docs / faq_build.md

diff --git a/docs/faq_build.md b/docs/faq_build.md
index 00a0d386b913f8eb582146f70ab03ae8d1c0f669..d920d27e2a45ce5a9b4a5b2c6ba5581273258d20 100644 (file)
--- a/docs/faq_build.md
+++ b/docs/faq_build.md
@@ -37,6 +37,10 @@ SUBSYSTEMS=="usb", ATTRS{idVendor}=="03eb", ATTRS{idProduct}=="2ff0", MODE:="066
 SUBSYSTEMS=="usb", ATTRS{idVendor}=="feed", MODE:="0666"
 ```
 
+### Serial device is not detected in bootloader mode on Linux
+Make sure your kernel has appropriate support for your device. If your device uses USB ACM, such as 
+Pro Micro (Atmega32u4), make sure to include `CONFIG_USB_ACM=y`. Other devices may require `USB_SERIAL` and any of its sub options.
+
 ## Unknown Device for DFU Bootloader
 
 If you're using Windows to flash your keyboard, and you are running into issues, check the Device Manager.  If you see an "Unknown Device" when the keyboard is in "bootloader mode", then you may have a driver issue. 
@@ -105,10 +109,12 @@ The solution is to remove and reinstall all affected modules.
 ```
 brew rm avr-gcc
 brew rm dfu-programmer
+brew rm dfu-util
 brew rm gcc-arm-none-eabi
 brew rm avrdude
 brew install avr-gcc
 brew install dfu-programmer
+brew install dfu-util
 brew install gcc-arm-none-eabi
 brew install avrdude
 ```
@@ -124,5 +130,5 @@ For now, you need to rollback avr-gcc to 7 in brew.
 ```
 brew uninstall --force avr-gcc
 brew install avr-gcc@7
-brew link avr-gcc@7
+brew link --force avr-gcc@7
 ```