[alsa-devel] [PATCH v2] ALSA: dice: improve support for ancient firmware for DICE

[Takashi Iwai]

On Tue, 24 Apr 2018 15:24:32 +0200,
Takashi Sakamoto wrote:
> 
> In early stage of firmware SDK, DICE seems to lose its backward
> compatibility due to some registers on global address section. I found
> this with Alesis Multimix 12 FireWire with ancient firmware (approx.
> shipped version).
> 
> According to retrieved log from the unit, global section has 96 byte
> space. On the other hand, current version of ALSA dice driver assumes
> that all of supported unit has at least 100 byte space.
> 
> $ ./firewire-request /dev/fw1 read 0xffffe0000000 28
> result: 000: 00 00 00 0a 00 00 00 18 00 00 00 22 00 00 00 8a
> result: 010: 00 00 00 ac 00 00 01 12 00 00 00 00 00 00 00 00
> result: 020: 00 00 00 00 00 00 00 00
> 
> This commit adds support for the ancient firmware. Check of global section
> is loosened to accept the smaller space. The lack of information is
> already compensated by hard-coded parameters.
> 
> I experienced that the latest version of Windows driver for this model
> can't handle this unit, too. This means that TCAT releases firmware SDK
> without backward compatibility for the ancient firmware.
> 
> Below list is a early history of driver/firmware package released by
> Alesis. I investigated on wayback machine on Internet Archive:
>  * Unknown: PAL v1.0.41.2, firmware v1.0.3
>  * Mar 2006: PAL v1.54.0, firmware v1.0.4
>  * Dec 2006: PAL v2.0.0.2, firmware v2.0
>  * Jun 2007: PAL v3.0.41.5, firmware v2.0
>  * Jul 2007: PAL v3.0.56.2. firmware v2.0
>  * Jan 2008: PAL v3.0.81.1080, firmware v2.0
> 
> If I can assume that firmware version is the same as DICE version, DICE
> version for the issued firmware may be v1.0.3. According to code base of
> userspace driver project (FFADO), I can read DICE v1.0.4 supports global
> space larger than 100 byte. I guess the smaller space of global section is
> a feature of DICE v1.0.3.
> 
> Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>

Applied now, thanks.


Takashi