Johan Bernhardsson, regarding your comment from https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1530476/comments/23 :

>"pm test none failed."

Are you saying that none of the pm tests failed?

Despite this, as per https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1530476/+attachment/4578288/+files/devices.txt :
[ 1414.148685] ------------[ cut here ]------------
[ 1414.148720] WARNING: CPU: 2 PID: 3775 at /home/kernel/COD/linux/drivers/gpu/drm/i915/intel_uncore.c:599 hsw_unclaimed_reg_debug+0x69/0x90 [i915]()
[ 1414.148723] Unclaimed register detected after reading register 0x70008
[ 1414.148725] Modules linked in: rfcomm drbg ansi_cprng ctr ccm xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ipt_REJECT nf_reject_ipv4 xt_tcpudp bridge stp llc ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter ip_tables x_tables bnep snd_hda_codec_hdmi hid_lenovo cdc_mbim cdc_wdm uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_core btusb btrtl btbcm cdc_ncm btintel usbnet videodev snd_usb_audio usbhid cdc_acm snd_usbmidi_lib mii bluetooth media hid_sensor_rotation arc4 hid_sensor_gyro_3d hid_sensor_custom nls_iso8859_1 hid_sensor_incl_3d hid_sensor_accel_3d hid_sensor_als hid_sensor_magn_3d hid_sensor_trigger industrialio_triggered_buffer kfifo_buf industrialio
[ 1414.148774]  hid_sensor_iio_common hid_sensor_hub iwlmvm wacom mac80211 acer_wmi sparse_keymap intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp snd_soc_rt286 iwlwifi snd_soc_rl6347a kvm_intel snd_soc_core kvm i915 snd_compress drm_kms_helper cfg80211 ac97_bus drm irqbypass snd_pcm_dmaengine i2c_algo_bit fb_sys_fops syscopyarea sysfillrect sysimgblt crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd joydev input_leds serio_raw intel_pch_thermal lpc_ich snd_hda_intel snd_hda_codec shpchp snd_hda_core snd_hwdep snd_pcm mei_me mei processor_thermal_device intel_soc_dts_iosf thinkpad_acpi nvram mac_hid snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device snd_timer soc_button_array snd soundcore int3402_thermal int3403_thermal
[ 1414.148822]  int340x_thermal_zone int3400_thermal dw_dmac 8250_dw snd_soc_sst_acpi snd_soc_sst_match acpi_thermal_rel dw_dmac_core i2c_designware_platform spi_pxa2xx_platform i2c_designware_core parport_pc ppdev lp parport autofs4 psmouse ahci libahci wmi sdhci_acpi video sdhci i2c_hid hid fjes
[ 1414.148842] CPU: 2 PID: 3775 Comm: suspend.sh Not tainted 4.5.0-040500rc5-generic #201602201730
[ 1414.148844] Hardware name: LENOVO 20CGCTO1WW/20CGCTO1WW, BIOS N17ET83W (1.83 ) 12/02/2015
[ 1414.148847]  0000000000000086 000000008ee25057 ffff8801c3ba7a30 ffffffff813dfc93
[ 1414.148852]  ffff8801c3ba7a78 ffffffffc0554168 ffff8801c3ba7a68 ffffffff81080e72
[ 1414.148855]  ffff88021ef40000 0000000000070008 0000000000000000 0000000000000206
[ 1414.148859] Call Trace:
[ 1414.148865]  [<ffffffff813dfc93>] dump_stack+0x63/0x90
[ 1414.148870]  [<ffffffff81080e72>] warn_slowpath_common+0x82/0xc0
[ 1414.148873]  [<ffffffff81080f0c>] warn_slowpath_fmt+0x5c/0x80
[ 1414.148895]  [<ffffffffc04ca729>] hsw_unclaimed_reg_debug+0x69/0x90 [i915]
[ 1414.148915]  [<ffffffffc04cdf34>] gen6_read32+0x94/0x1f0 [i915]
[ 1414.148934]  [<ffffffffc04ce690>] ? gen8_write8+0x230/0x230 [i915]
[ 1414.148956]  [<ffffffffc04f6815>] intel_modeset_setup_hw_state+0x6c5/0xe30 [i915]
[ 1414.148976]  [<ffffffffc03272a0>] ? drm_atomic_get_connector_state+0x110/0x190 [drm]
[ 1414.148999]  [<ffffffffc04f979f>] intel_display_resume+0xff/0x150 [i915]
[ 1414.149014]  [<ffffffffc0474acd>] i915_drm_resume+0xdd/0x170 [i915]
[ 1414.149029]  [<ffffffffc0474b85>] i915_pm_resume+0x25/0x30 [i915]
[ 1414.149034]  [<ffffffff81431694>] pci_pm_resume+0x64/0xa0
[ 1414.149037]  [<ffffffff81431630>] ? pci_pm_thaw+0x90/0x90
[ 1414.149041]  [<ffffffff81550e8e>] dpm_run_callback+0x4e/0x130
[ 1414.149044]  [<ffffffff81551423>] device_resume+0xd3/0x1f0
[ 1414.149048]  [<ffffffff815528c2>] dpm_resume+0x112/0x2f0
[ 1414.149051]  [<ffffffff81552e41>] dpm_resume_end+0x11/0x20
[ 1414.149055]  [<ffffffff810ce90a>] suspend_devices_and_enter+0x16a/0x720
[ 1414.149058]  [<ffffffff810cf217>] pm_suspend+0x357/0x400
[ 1414.149061]  [<ffffffff810cda5c>] state_store+0x7c/0xe0
[ 1414.149065]  [<ffffffff813e1dcf>] kobj_attr_store+0xf/0x20
[ 1414.149069]  [<ffffffff81295f87>] sysfs_kf_write+0x37/0x40
[ 1414.149073]  [<ffffffff8129537d>] kernfs_fop_write+0x11d/0x170
[ 1414.149077]  [<ffffffff812142f7>] __vfs_write+0x37/0x120
[ 1414.149082]  [<ffffffff81389118>] ? apparmor_file_permission+0x18/0x20
[ 1414.149085]  [<ffffffff8134979d>] ? security_file_permission+0x3d/0xc0
[ 1414.149088]  [<ffffffff810ca572>] ? percpu_down_read+0x12/0x50
[ 1414.149092]  [<ffffffff81214c19>] vfs_write+0xa9/0x1a0
[ 1414.149095]  [<ffffffff81233545>] ? set_close_on_exec+0x35/0x70
[ 1414.149099]  [<ffffffff81215b45>] SyS_write+0x55/0xc0
[ 1414.149103]  [<ffffffff81822a36>] entry_SYSCALL_64_fastpath+0x16/0x75
[ 1414.149105] ---[ end trace f592ea7dd3129e0f ]---

This seems like a good start to hone in on.

To clarify, did you test each of the suspend types more than once?