[pvrusb2] cx2341x firmware size is no longer a multiple of 8KB

[Mike Isely]

Recently a new cx2341x firmware image became available on the ivtvdriver 
web site.  However this image is no longer 256KB in length, which means 
it likely isn't a multiple of 8KB in size.

Historically, the pvrusb2 driver enforced a requirement that the 
firmware image must be a multiple of 8KB (i.e. 8192 bytes) in size.  
The reason for this is that the implementation of the code expected to 
load exact 8KB chunks and would not work properly if an exact-sized 
chunk could not be loaded.  Thus the pvrusb2 driver would not be able to 
load this newer firmware.

It was a silly limit.  I've already updated the pvrusb2 driver with a 
better loading algorithm that lifts this limit.  The 20070207 snapshot 
is the first one with this change:

  http://www.isely.net/pvrusb2/history.html#pvrusb2-mci-20070207

This same change has been accepted into the v4l-dvb repository (on Feb 
8th).  And this change should appear in the 2.6.21 kernel.  In any of 
those cases you should be fine with the larger firmware image.

However, if you run anything older, the pvrusb2 driver will reject the 
cx2341x firmware and you'll get a complaint in the log that will look 
like this:

  pvrusb2: size of v4l-cx2341x-enc.fw firmware must be a multiple of 8192B

You *will* hit this if you try the larger firmware using the pvrusb2 
driver from the 2.6.20, for example.

If you hit this problem, you can solve it by doing any one of the 
following:

1. Build and install a standalone snapshot (20070207 or later).

2. Build and install the current v4l-dvb repository (see linuxtv.org).

3. Try out a 2.6.21 kernel (once it becomes available).

 -or-

4. Use the instructions on the pvrusb2 site to automatically extract the 
firmware yourself from the Hauppauge driver CD rather than downloading 
the larger image from ivtvdriver.org, in which case you'll likely still 
get a 256KB cx2341x firmware image.  (Or grab an older firmware image 
from ivtvdriver.org.)

  -Mike


-- 
                        |         Mike Isely          |     PGP fingerprint
     Spammers Die!!     |                             | 03 54 43 4D 75 E5 CC 92
                        |   isely @ pobox (dot) com   | 71 16 01 E2 B5 F5 C1 E8
                        |                             |