Problem with restricted I2C algorithms in kernel 2.6.26!
From: D. Kelly
Date: Wed Jul 16 2008 - 15:34:17 EST
The patch at the preceeding url disables the users ability to select
I2C algorithms. Specifically the reason stated was:
"The algorithm drivers are
helper drivers that are selected automatically
as needed. There's no point in listing them in the config menu, it can
only confuse users and waste their time."
The algorithm drivers will not be 'selected automatically as needed'
if the user is compiling something outside of the kernel that requires
them! Just one example, there are drivers found in the V4L dvb driver
tree that require i2c bit-banging be enabled. The drivers are now
broken because the user is not allowed to enable bit-banging himself.
The only way around this is to revert the patch manually or enable
something else in the kernel, that he doesn't need, just to get
It's a very bad idea to assume that nothing built outside of the
kernel may need i2c algorithms. Furthermore, the whole point of being
able to customize your kernel is so you can select only the things
which you need. It makes no good sense to intentionally
disable/restrict the users ability to do so. Additionally, assuming
the ability to select i2c algorithms will only confuse the user and
waste their time is ridiculous. The user should be allowed to decide
for himself what he needs regarding this!
One of the biggest reasons people choose to compile things from
cvs/svn/mercurial/etc. is because it gives them access to newer bug
fixes and support for things not yet present in the kernel source. A
perfect example, the multiproto dvb driver tree. Users wanting
support for dvb-s2 devices have to compile drivers outside of the
kernel because it's simply not available in the kernel and won't be
for some time.
I've contacted one of the i2c subsystem maintainers, Jean Delvare, but
unfortunately he doesn't seem to care about this problem and his
advice in dealing with it is to "Just get these drivers merged in the
kernel. Ah ah ah!"...
Clearly the more sane and reasonable solution is to not cripple the
menu options in the first place, especially when it creates no benefit
and only serves to limit/restrict the users ability to select what he
needs. I'm asking that the patch be reverted and anyone in agreement
to please voice their opinion here in public.
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