Tried the latest kernel and have the issue where the LCD backlight does
not light (ie dark screen) after the kernel has booted.

It appears that there is a 'oops' with the nsc-ircc driver, and I assume
that this is the root of the problem. 4.3.0rc6 and rc7 are bad, rc2 seems
OK.

--
Oct 23 07:35:08 retrobox kernel: [   23.640044] nsc-ircc, driver loaded
(Dag Brattli)
Oct 23 07:35:08 retrobox kernel: [   23.640730] BUG: unable to handle
kernel NULL pointer dereference at 00000130
Oct 23 07:35:08 retrobox kernel: [   23.641422] IP: [<c1017802>]
arch_dma_alloc_attrs+0x12/0x70
Oct 23 07:35:08 retrobox kernel: [   23.641953] *pdpt = 00000000363cb001
*pde = 0000000000000000
Oct 23 07:35:08 retrobox kernel: [   23.642517] Oops: 0000 [#1] SMP
Oct 23 07:35:08 retrobox kernel: [   23.642849] Modules linked in:
nsc_ircc(+) snd_seq_device snd_timer snd floppy(+) irda soundcore
crc_ccitt shpchp 8250_fintek video mac_hid parport_pc ppdev lp parport
autofs4 e1000e psmouse ptp pata_acpi pps_core
Oct 23 07:35:08 retrobox kernel: [   23.644011] CPU: 0 PID: 267 Comm:
systemd-udevd Not tainted 4.3.0-rc6-g920+ #10
Oct 23 07:35:08 retrobox kernel: [   23.644011] Hardware name: LENOVO
2008VPX/2008VPX, BIOS 79ETE5WW (2.25 ) 08/27/2009
Oct 23 07:35:08 retrobox kernel: [   23.644011] task: f37c71c0 ti:
f63cc000 task.ti: f63cc000
Oct 23 07:35:08 retrobox kernel: [   23.644011] EIP: 0060:[<c1017802>]
EFLAGS: 00010202 CPU: 0
Oct 23 07:35:08 retrobox kernel: [   23.644011] EIP is at
arch_dma_alloc_attrs+0x12/0x70
Oct 23 07:35:08 retrobox kernel: [   23.644011] EAX: f63cdd08 EBX:
00000000 ECX: 000080d0 EDX: f63cdd0c
Oct 23 07:35:08 retrobox kernel: [   23.644011] ESI: f6afe66c EDI:
c1a305c0 EBP: f63cdd00 ESP: f63cdcfc
Oct 23 07:35:08 retrobox kernel: [   23.644011]  DS: 007b ES: 007b FS:
00d8 GS: 00e0 SS: 0068
Oct 23 07:35:08 retrobox kernel: [   23.644011] CR0: 80050033 CR2:
00000130 CR3: 36945200 CR4: 000006f0
Oct 23 07:35:08 retrobox kernel: [   23.644011] Stack:
Oct 23 07:35:08 retrobox kernel: [   23.644011]  00003830 f63cdd20
f8532a11 00000000 000080d0 f63cdd68 f6afe000 f6afe500
Oct 23 07:35:08 retrobox kernel: [   23.644011]  f6afe598 f63cdd68
f85371c9 c19ce2e2 f85340bc 00000000 f63cddc8 f63cdd58
Oct 23 07:35:08 retrobox kernel: [   23.644011]  c10b9be1 00000000
00000006 00000000 00000000 f8533267 f63cdd6c f63cdd60
Oct 23 07:35:08 retrobox kernel: [   23.644011] Call Trace:
Oct 23 07:35:08 retrobox kernel: [   23.644011]  [<f8532a11>]
dma_alloc_attrs.constprop.18+0x4b/0x71 [nsc_ircc]
Oct 23 07:35:08 retrobox kernel: [   23.644011]  [<f85371c9>]
nsc_ircc_open+0x1c9/0x42c [nsc_ircc]
Oct 23 07:35:08 retrobox kernel: [   23.644011]  [<c10b9be1>] ?
vprintk_default+0x41/0x60
Oct 23 07:35:08 retrobox kernel: [   23.644011]  [<f85375e4>]
nsc_ircc_init+0x1b8/0xbd4 [nsc_ircc]
Oct 23 07:35:08 retrobox kernel: [   23.644011]  [<c1002136>]
do_one_initcall+0xc6/0x200
Oct 23 07:35:08 retrobox kernel: [   23.644011]  [<f853742c>] ?
nsc_ircc_open+0x42c/0x42c [nsc_ircc]
Oct 23 07:35:08 retrobox kernel: [   23.644011]  [<f853742c>] ?
nsc_ircc_open+0x42c/0x42c [nsc_ircc]
Oct 23 07:35:08 retrobox kernel: [   23.644011]  [<c1002136>] ?
do_one_initcall+0xc6/0x200
Oct 23 07:35:08 retrobox kernel: [   23.644011]  [<f853742c>] ?
nsc_ircc_open+0x42c/0x42c [nsc_ircc]
Oct 23 07:35:08 retrobox kernel: [   23.644011]  [<c171d8db>] ?
preempt_schedule_common+0x1b/0x40
Oct 23 07:35:08 retrobox kernel: [   23.644011]  [<c171d925>] ?
_cond_resched+0x25/0x30
--

Cheers,
Simon.