[sane-devel] HAL and scanners.

[Étienne Bersac]

Hi,

In january 2007, happened a very good discussion this list about SANE
and HAL wich led to shipping a basic fdi.
http://lists.alioth.debian.org/pipermail/sane-devel/2007-January/018343.html. 

Currently, sane-desc generate a very basic fdi which only badge device
as scanner and add a property "scanner.access_method" hardcoded to
"proprietary", the latter is pretty useless ;)

Please keep in mind that supporting HAL does NOT mean depending on HAL
nor breaking API.


Abel Deuring did a very nice job on sane-fdi, a parser for .desc file
that provide much useful information right in the fdi. Sadly, the
discussion stopped without a lot of success. I updated the sane-fdi
script from Abel following the advice from Abel and Johannes Meixner.

A device rule looks like :

  <device>
    <match key="usb.vendor_id" int="0x04a9">
      <match key="usb.product_id" int="0x2207">
        <append key="info.capabilities" type="strlist">scanner</append>
        <append key="scanner.api" type="strlist">sane</append>
        <append key="scanner.sane.model" type="strlist">Canon CanoScan N1220U</append>
        <append key="scanner.sane.backends" type="strlist">plustek</append>
        <append key="scanner.sane.backends.plustek.supportstatus" type="strlist">complete</append>
        <append key="scanner.sane.backends.plustek.comment" type="strlist">Identical to UMAX 3400</append>
      </match>
    </match>
  </device>

The updated sane-fdi script is available at
http://bersace03.free.fr/pub/Development/Scanner/sane-fdi .



There is still one thing needed to get full HAL support by SANE, build
the SANE device name from those infos.

One goal would be to allow frontend to provide an entry for each backend
allowing user to select the backend to use. Using e.g. "Cannon CanoScan
N1220U (complete support with plustek driver)" along "Canon CanoScan
N1220U (complete support with umax driver)" will allow user to easily
select driver.

According to discussion about HAL and SANE last year, seems that the
"udi:<backend>:<udi>" would be the solution for SANE to support HAL
(without depending on it). See
http://lists.alioth.debian.org/pipermail/sane-devel/2007-January/018353.html for details.


So, can we move forward ? :)

Regards,
Étienne.
-- 
E Ultreïa !