Since I don’t currently have the necessary time, I wrote it off as just another one of my many dead-end interests, but I nevertheless remained subscribed to the linux-acpi mailing list and the curiosity was still there, so it was a nice surprise to read a couple of posts by Mathew Garret on the subject, elucidating some bits of technicality, and I just decided to show some appreciation by posting about it! (I figure there’s not enough appreciation out there, generally speaking…)

Who knows, maybe someday I’ll get my act together and be able to contribute some code?

The new Acer Aspire Timeline 3810T is pretty nice and I got it at a surprise sale, so it was definitely worth it.
This time around I had – at least partially – done my homework and already knew about some possible hardware issues. Installing Debian wasn’t problem-free, but it was certainly made harder by my stubborn expedition into let’s-try-it-the-stupid-way-land (not unlike my recent run-in with dpkg):
Lenny’s kernel didn’t recognize the network cards and the daily-built installer images didn’t even boot (perhaps related to #541115), so I diligently spent the next couple of hours trying to build my own Frankenstein version of d-i with varied levels of failure. This didn’t accomplish much besides leaving me with a renewed respect for the d-i team.
In the end I gave up looking for ways to complicate things, simply installed a base Lenny system and copied a new kernel package via USB-stick (actually compiled my own 2.6.31-rc5, since 2.6.30 still didn’t correctly support the atl1c Ethernet card: recognized, but non-working).

After that slightly bumpy start, everything went totally smooth. [UPDATE: I just noticed the internal microphone wasn't working. Adding "option snd-hda-intel model=fujitsu" to modprobe's configurations fixes the issue. It also works with model=eeepc-p901, but the sound quality was worse. I filed a bug on ALSA to support this out-of-the-box in the future.]

As for the IDE vs. AHCI problems reported in the Ubuntu help site, I don’t know if it affects the Lenny installer because I switched to IDE mode before installing and back to AHCI only when 2.6.31 was already running.

My quick overview of the laptop:

Pros:

• The battery’s really nice: ~6 hours with wireless on, medium brightness and normal usage (including some quick compiling).
• The screen’s also pretty sharp and the size seems to hit my personal sweet spot between too small to use and too big to carry.
• The keyboard seems a bit strange at first, but after a few hours I’ve gotten totally used to it and now I actually find it a positive point. It’s pretty hard to find a nice keyboard on a small(ish) laptop.
• It isn’t a performance machine, but it’s a sensibly quicker and more responsive than all netbooks I’ve tried.

Cons:

• I haven’t tried it very hard, but I didn’t manage to make suspend work. Still haven’t given up on it, though… [UPDATE: suspend works like a charm with the solution found in this bug report]
• Multi-touch support doesn’t feel very usable, but perhaps it’s just hard to master (it could also be lack of tuning on the synclient settings)
• The touchpad buttons are annoyingly a single piece of plastic. That means it’s pretty hard to press both at the same time to use 3rd button emulation (in case multi-touch doesn’t cut it for you).
• Even thought the CPU apparently has the VT extension, it seems to be disabled in the BIOS (tested versions 1.04 and 1.10).[UPDATE: as seen in the comments, there are a couple of workarounds] [UPDATE #2: BIOS v1.14 seems to enable it.]
• For those whose FOSS principles matter: the wireless LAN requires the non-free iwlwifi firmware.

It may seem like a lot of cons, but I’m pretty happy with it. Perhaps it’s just my frustration with the old laptop making the new one look better, or perhaps it’s just my newgadgetophilia speaking.
Regardless, the final test drive will be next week’s FrOSCon.

After many hours reading the ACPI spec and fiddling with the DSDT code in my laptop trying to solve the problems with the fan, I now finally have a thermal zone that reports the (somewhat) accurate temperature and a fan that (somewhat) works.

As can be read in the linux-acpi thread, it’s not really a solution, more like a fluke, but if someone’s ran into the same problem and has a L300 21C, feel free to grab the updated DSDT and give it a spin.

Some notes:

• I wasn’t able to upload it to the DSDT override database on the old ACPI site; the new one says it should still work, but it doesn’t, so I’m hosting it here instead.
• There’s still some debugging output there, if someone wants to try hacking it a bit further.
• The active trip points reported are bogus, since the fan is controlled by something else. The kernel should still respect the passive, hot and critical trip points though, but I didn’t feel like putting my laptop through those tests…
• I didn’t solve the many warnings generated by the Intel compiler. They’re inside functions not related to my problem and the code is quite unwieldy for my level of DSDT-fu.
• I don’t think I’ve made any drastic changes, but if you laptop suddenly catches fire, you’re on your own! (I’ll update this post if mine does…)

UPDATE: I’ve run into some problems with kernel 2.6.30.

Being the cheap bastard that I am, I found a nice bargain some weeks ago for a Toshiba Satellite L300 21C and decided to take it instead of going for the slightly more expensive, slightly less equipped and overall just geek-friendlier Thinkpad*.

The L300 21C (“lshal | grep system.hardware.version” reports ‘PSLB8E-0H301VGR’) packs 4G of ram (2x 2G), a 250G SATA disk, an Intel 4500MHD card (which I specifically sought for the supposed good Linux support) and an Atheros AR242x wireless card.
It’s nothing special, but it performs decently enough.

I obviously wanted to install Debian on it before even turning it on and seeing the face of the operating system that came preinstalled, but at the time I bought it Lenny hadn’t been released yet, so I grabbed the RC2 images. Since the differences between RC2 and Lenny are probably negligible, this post should apply to Lenny as well.

The first thing that got my attention was that the wireless doesn’t work with the ath5k module from 2.6.26 – shipped with Lenny, so I could either upgrade my kernel to 2.6.28 or install the MadWifi modules.
The next problem helped decide the solution for the first one: suspend wasn’t working and it turns out it was a combination of the EXA AccelMethod not playing well with the intel driver and the Hal quirks database having an entry for the Satellite L30 which matches too broadly and introduces the wrong quirks for the L300′s suspend.

For the EXA part, upgrading X.org to 1.5.99.902 and the intel driver to 2.6.1 (currently in experimental) and changing the AccelMethod to UXA was the only option. This in turn meant upgrading the kernel to 2.6.28 because of the GEM support needed by UXA, thus also solving the first problem with the wireless card.

The Hal part was solved by adding the following quirks to Hal’s FDI database (/etc/hal/fdi/information/, in Debian’s case):

< ?xml version="1.0" encoding="ISO-8859-1"?>
<deviceinfo version="0.2">
  <device>
    <match key="system.hardware.vendor" string="TOSHIBA">
      </match><match key="system.hardware.product" string="Satellite L300">
        <merge key="power_management.quirk.s3_bios" type="bool">false</merge> <!-- wrongly added by L30 rule -->
        <merge key="power_management.quirk.s3_mode" type="bool">false</merge> <!-- wrongly added by L30 rule -->
        <merge key="power_management.quirk.vbestate_restore" type="bool">true</merge>
      </match>
    </device>
</deviceinfo>

After that, suspend to memory worked like a charm.

I haven’t really tested suspend to disk, since I’m using home+swap inside encrypted LVM, but I may check it out a bit later. For now suspend to memory is all I needed.

The laptop still has the following unsolved problems:

The screen sucks, even for a laptop. It looks blueish, blows the white areas’ brightness – regardless of gamma setting – and has a terrible contrast ratio which I still couldn’t go around. I tried xcalib and changing X.org’s gamma settings, to no avail. Next desperate step will be fiddling with compiz’s color filter, since the intel driver AFAIK doesn’t have a color correction interface.
I’m still not sure if this is a driver issue or a monitor issue, since the proprietary operating system that came preinstalled also showed most of these issues (I installed it again just to make this test).

Making the screen problems a bit worse, UXA still has some problematic interactions with compiz that mess with some opacity operations. I expect this should be fixed in a future release of X.org, perhaps when the UXA work gets merged back into EXA.

But the biggest problem I’ve encountered so far is with the fan. Apparently the fan’s thermal control is borked and after reaching a certain temperature the fan kicks to full power and doesn’t slow down until either shutting the laptop down or suspending it. This could be an ACPI bug, but I suspect otherwise because disabling ACPI on boot-time (acpi=ht) doesn’t have any effect. I’ve even tried following the advices on the ACPI site to debug this problem and I’m running 2.6.29-RC5 to make sure this hasn’t been solved already, but still haven’t gotten anything useful out of it. (I also ran into this problem with 2.6.26 and 2.6.28)
My best (but still not very good) guess would be that the BIOS in the laptop (Insyde H2) has some proprietary non-ACPI way of fine-tuning the fan speed, probably off-loading the task to a driver, which nobody has implemented for Linux yet. Might be a nice little project, if I had the slightest idea where to start, but unfortunately I have zero experience reverse engineering BIOS code…

In summary I’d suggest that anyone wanting to buy this laptop don’t be an idiot like I was and just research a little bit more. It’s not a bad machine, for the price, but it still has these nagging problems that spoil the feeling of running a nicely configured system and specially this last fan problem is potentially a show stopper.

* So geek friendly, in fact, that I felt completely out of place at FOSDEM. Like the only kid with the wrong toy.

UPDATE: pseudo-solution found here.