MacBookPro11,1 (Late 2013 Haswell) has no sound

I installed Ubuntu 13.10 on a new MacBook Pro (Late 2013, 13-inch Haswell retina). The speakers did not work after installation, and after I fixed it, it would not work after suspend. It turns out some of the flags were not set correctly. I can fix these problems but it would be nice to have them fixed at installation.

The problem can be seen in the GPIO section in /proc/asound/card1/codec#0 (card0 is for HDMI). After boot, the GPIO flags for IO[0] were

GPIO: io=6, o=2, i=0, unsolicited=1, wake=1
  IO[0]: enable=1, dir=1, wake=0, sticky=0, data=0, unsol=0

If data were set to 1, sound would work! I fixed this by installing alsa-tools and adding to /etc/rc.local a line:

hda-verb /dev/snd/hwC1D0 0x1 set_gpio_data 1

After resuming from suspend, the GPIO flags for IO[0] became

GPIO: io=6, o=2, i=0, unsolicited=1, wake=1
  IO[0]: enable=0, dir=0, wake=0, sticky=0, data=0, unsol=0

Here, three flags were set to 0. I fixed this by adding to /etc/pm/sleep.d/99_myfix a few lines:

#!/bin/sh
case "$1" in
 resume|thaw)
  hda-verb /dev/snd/hwC1D0 0x1 set_gpio_mask 1
  sleep 1
  hda-verb /dev/snd/hwC1D0 0x1 set_gpio_direction 1
  sleep 1
  hda-verb /dev/snd/hwC1D0 0x1 set_gpio_data 1
  ;;
esac
---
ApportVersion: 2.12.5-0ubuntu2.1
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: lic3 3717 F.... pulseaudio
 /dev/snd/controlC0: lic3 3717 F.... pulseaudio
DistroRelease: Ubuntu 13.10
HibernationDevice: RESUME=UUID=a2156b27-f1e5-4408-9fb3-491e6f8229fb
InstallationDate: Installed on 2013-11-06 (21 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1)
MachineType: Apple Inc. MacBookPro11,1
MarkForUpload: True
NonfreeKernelModules: wl
Package: linux (not installed)
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.11.0-13-generic.efi.signed root=UUID=b62d2699-f735-46a1-8e31-23146f2497a3 ro libata.force=noncq quiet splash vt.handoff=7
ProcVersionSignature: Ubuntu 3.11.0-13.20-generic 3.11.6
RelatedPackageVersions:
 linux-restricted-modules-3.11.0-13-generic N/A
 linux-backports-modules-3.11.0-13-generic N/A
 linux-firmware 1.116
Tags: saucy saucy
Uname: Linux 3.11.0-13-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
dmi.bios.date: 09/22/2013
dmi.bios.vendor: Apple Inc.
dmi.bios.version: MBP111.88Z.0133.B00.1309220923
dmi.board.asset.tag: Base Board Asset Tag#
dmi.board.name: Mac-189A3D4F975D5FFC
dmi.board.vendor: Apple Inc.
dmi.board.version: MacBookPro11,1
dmi.chassis.type: 10
dmi.chassis.vendor: Apple Inc.
dmi.chassis.version: Mac-189A3D4F975D5FFC
dmi.modalias: dmi:bvnAppleInc.:bvrMBP111.88Z.0133.B00.1309220923:bd09/22/2013:svnAppleInc.:pnMacBookPro11,1:pvr1.0:rvnAppleInc.:rnMac-189A3D4F975D5FFC:rvrMacBookPro11,1:cvnAppleInc.:ct10:cvrMac-189A3D4F975D5FFC:
dmi.product.name: MacBookPro11,1
dmi.product.version: 1.0
dmi.sys.vendor: Apple Inc.