i2c-tools: add compatibility for python2/3 to py-smbus

Hi again Michael,

On Thu, 22 Jan 2015 09:56:58 +0100, Michael Mercier wrote:
> I just tried you patch and I got an error when I try to import the 
> smbus python package:
> 
> import smbus
> 
> ImportError: 
> /usr/local/lib/python3.2/dist-packages/smbus.cpython-32mu.so: undefined 
> symbol: i2c_smbus_process_call
> 
> Any idea?

Hmm, OK, I think I see what's going on here.

There are two i2c-tools branches: the stable branch (3.1) and the
development branch (SVN trunk.) The patch I sent was for the
development branch.

One important difference between the two branches is that, in the
stable branch, the i2c API is implemented as a set of inline functions,
while in the development branch it is a library. I don't think that
py-smbus was properly ported so most likely it was already broken
before my patch. I suppose you are using SVN trunk and this is why you
have this linking problem?

If that is the case, then maybe the following patch will do the trick:

---
 py-smbus/Module.mk |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)


But please keep in mind that my python knowledge is non-existent so it
might be plain wrong. Hopefully Angelo can comment on this.

Thanks a lot!

It was a linking problem. I applied the patch and I it works for both 
python2 and python3.

For those who are interested you can choose to the python version with 
the PYTHON variable:
make install # use "python" so it depends on your system configuration
make install PYTHON=python2 # for python 2 explicitly
make install PYTHON=python3 # for python 3 explicitly


I have only tested read_i2c_block_data write_i2c_block_data for python 
3.2 and python 2.7.

I think you can push these patchs upstream.

Thanks again,

Michael Mercier

Le jeu. 22 janv. 2015 à 11:49, Jean Delvare <jdelvare@suse.de> a 
écrit :
> Hi again Michael,
> 
> On Thu, 22 Jan 2015 09:56:58 +0100, Michael Mercier wrote:
>>  I just tried you patch and I got an error when I try to import the
>>  smbus python package:
>> 
>>  import smbus
>> 
>>  ImportError:
>>  /usr/local/lib/python3.2/dist-packages/smbus.cpython-32mu.so: 
>> undefined
>>  symbol: i2c_smbus_process_call
>> 
>>  Any idea?
> 
> Hmm, OK, I think I see what's going on here.
> 
> There are two i2c-tools branches: the stable branch (3.1) and the
> development branch (SVN trunk.) The patch I sent was for the
> development branch.
> 
> One important difference between the two branches is that, in the
> stable branch, the i2c API is implemented as a set of inline 
> functions,
> while in the development branch it is a library. I don't think that
> py-smbus was properly ported so most likely it was already broken
> before my patch. I suppose you are using SVN trunk and this is why you
> have this linking problem?
> 
> If that is the case, then maybe the following patch will do the trick:
> 
> ---
>  py-smbus/Module.mk |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> --- i2c-tools.orig/py-smbus/Module.mk	2012-04-26 12:05:55.351086796 
> +0200
> +++ i2c-tools/py-smbus/Module.mk	2015-01-22 11:47:06.524806243 +0100
> @@ -12,7 +12,7 @@ PY_SMBUS_DIR := py-smbus
>  PYTHON ?= python
>  DISTUTILS := \
>  	cd $(PY_SMBUS_DIR) && \
> -	CPPFLAGS="$(CPPFLAGS) -I../include" $(PYTHON) setup.py
> +	CPPFLAGS="$(CPPFLAGS) -I../include" LDFLAGS="$(LDFLAGS) -Llib 
> -li2c" $(PYTHON) setup.py
> 
>  all-python: $(INCLUDE_DIR)/i2c/smbus.h
>  	$(DISTUTILS) build
> 
> But please keep in mind that my python knowledge is non-existent so it
> might be plain wrong. Hopefully Angelo can comment on this.
> 
> --
> Jean Delvare
> SUSE L3 Support
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On Thu, 22 Jan 2015 14:28:10 +0100, Michael Mercier wrote:
> Thanks a lot!
> 
> It was a linking problem. I applied the patch and I it works for both 
> python2 and python3.
> 
> For those who are interested you can choose to the python version with 
> the PYTHON variable:
> make install # use "python" so it depends on your system configuration
> make install PYTHON=python2 # for python 2 explicitly
> make install PYTHON=python3 # for python 3 explicitly
> 
> 
> I have only tested read_i2c_block_data write_i2c_block_data for python 
> 3.2 and python 2.7.
> 
> I think you can push these patchs upstream.

Great, thanks for testing :)

On Thu, 22 Jan 2015 14:28:10 +0100, Michael Mercier wrote:
> I have only tested read_i2c_block_data write_i2c_block_data for python 
> 3.2 and python 2.7.
> 
> I think you can push these patchs upstream.

I committed both patches. I also added python 3 support to the stable
branch.

Hi Jean,

2015-01-26 12:46 GMT+01:00 Jean Delvare <jdelvare@suse.de>:
> On Thu, 22 Jan 2015 14:28:10 +0100, Michael Mercier wrote:
>> I have only tested read_i2c_block_data write_i2c_block_data for python
>> 3.2 and python 2.7.
>>
>> I think you can push these patchs upstream.
>
> I committed both patches. I also added python 3 support to the stable
> branch.

Any news on when the new i2c-tools stable release with python3 support
will be released?

Sincerely, Angelo

>
> --
> Jean Delvare
> SUSE L3 Support