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README.md

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 # pixelbookgohardware
-hardinfo report on pixelbook go with all kinds of useful info
+hardinfo report on pixelbook go with all kinds of useful info.
+
+As of right now, September 2020, the audio in Linux on Kaby Lake based devices (chromebooks) doesn't work. Here I'm trying to figure it out, since I just bought one and want to run linux on it, without chromeos.
+
+The hardware inside the Pixelbook Go (ATLAS) is KBL_DA7219_MAX98373.
+Decodes as KabyLake, with DA7219 and MAX98373 audio chips. 
+
+What I've tried so far:
+I installed stock ubuntu 20.04. No sound and no UHD graphics, but the system was stable/performing correctly with screen and keyboard backlight controls under the stock kernel. 
+I manually upgraded the kernel (dpkg method) to 5.8.9 (https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.8.9/) and the UHD screen started working perfectly.
+But still no sound.
+
+From a hardware perspective, it looks like both of these are already in upstream kernels since 5.6 (https://www.phoronix.com/scan.php?page=news_item&px=Linux-5.6-Sound), also seems to be the default hardware in Jasper Lake configs.
+
+So it seems that the issue is either: 1) a driver config problem or 2) a sound routing config problem.
+
+Based on the fact that no sound card shows up in Ubuntu, I'm guessing it's certainly 1 and probably 2 as well.
+
+Solutions people have come up with that I either haven't tried or didn't work for me:
+Gallium OS issue, solution for a different KBL configuration, the same approach might work, need to copy out the files.
+https://github.com/GalliumOS/galliumos-distro/issues/536 
+
+Github user @Flantel has also come up with a solution for the EVE chromebook (full on Pixelbook, not the Go variety):
+https://github.com/flantel/pixelbook-linux/blob/master/implementation-details.md#audio-support
+Should be possible to mod this by changing the various paths/files from EVE firmware to ATLAS. Being lazy I tried it without mods, and unsurprisingly it didn't work.
+
+Here's a relevant patch from Intel, https://patchwork.kernel.org/patch/10774385/ which I guess is now included?
+
+I also have an Acer Chromebook 14 running Ubuntu 20.04, got the sound fixed on that by swapping in this asound.state file 
+https://pastebin.com/c4qU9hdg
+However I haven't found a similar file lurking anywhere for the pixelbook go.
+
+In terms of drivers, following from the gallium os issue, I've been exploring my Chromebook /lib/firmware/intel folder. It contains:
+dsp_fw_578A29B8-0890-446F-A80A-2FE202AE0DBA.bin
+dsp_fw_B489C2DE-0F96-42E1-8A2D-C25B5091EE49.bin
+dsp_fw_C75061F3-F2B2-4DCC-8F9F-82ABB4131E66.bin
+dsp_fw_kbl.bin
+dsp_fw_kbl_v1037.bin
+dsp_fw_kbl_v2630.bin
+dsp_fw_kbl_v3266.bin
+dsp_fw_kbl_v3420.bin
+ibt-18-16-1.ddc
+ibt-18-16-1.sfi
+ipu3-fw.bin
+irci_irci_ecr-master_20161208_0213_20170112_1500.bin
+
+Within this folder, dsp_fw_kbl.bin is a symlink to dsp_fw_kbl_v3420.bin. This file shows up in stretch backports for https://packages.debian.org/stretch-backports/all/firmware-intel-sound/filelist
+
+Something else interesting I found on my journey - a bunch of config files for the intel drivers, but the DA7219 & MAX98373 combo isn't included.
+https://github.com/torvalds/linux/blob/master/sound/soc/intel/boards/Kconfig
+Could this be the missing piece? Maybe one of them. It might explain why the default intel sound driver doesn't show any devices. 
+
+Moving on to the config side, it sounds like UCM (Use Case Manager) for ALSA has evolved from version 1 to version 2 (UCM dir -> UCM2 dir), and presumably changed. This is an issue because any files exported from the chrome system (Kernel 4.4.223-17591-g3f222006e533) will also need to be updated to use UCM2, or a legacy UCM something magically installed.
+
+Finally, tangental to the above, seems like Mediatek are using a v.similar combo, but not identical here on their MT8183 SoC: https://cateee.net/lkddb/web-lkddb/SND_SOC_MT8183_DA7219_MAX98357A.html