[yocto] Kernel driver for Turbosight TBS6285 DVB card

[Chris Tapp]

On 21 Aug 2014, at 20:30, Bruce Ashfield <bruce.ashfield at windriver.com> wrote:

> On 14-08-21 03:11 PM, Chris Tapp wrote:
>> 
>> On 21 Aug 2014, at 19:28, Bruce Ashfield <bruce.ashfield at windriver.com> wrote:
>> 
>>> On 14-08-21 04:17 AM, Chris Tapp wrote:
>>>> On 21 Aug 2014, at 05:08, Bruce Ashfield <bruce.ashfield at gmail.com> wrote:
>>>> 
>>>>> On Wed, Aug 20, 2014 at 4:11 PM, Chris Tapp <opensource at keylevel.com> wrote:
>>>>>> Hi Bruce,
>>>>>> 
>>>>>> Thanks for the feedback.
>>>>>> 
>>>>>> On 20 Aug 2014, at 03:08, Bruce Ashfield <bruce.ashfield at windriver.com> wrote:
>>>>>> 
>>>>>>> On 2014-08-19, 5:26 PM, Chris Tapp wrote:
>>>>>>>> I need to include the kernel driver for the Turbosight TBS6285 DVB card in an image.
>>>>>>>> 
>>>>>>>> The official bundle at http://www.tbsdtv.com/download/document/common/tbs-linux-drivers_v140707.zip includes the drivers and a load of other "stuff" (e.g. a full V4L build).
>>>>>>>> 
>>>>>>>> LinuxTV.org have the drivers extracted into a .tar.bz2 at (e.g.) http://linuxtv.org/downloads/drivers/linux-media-LATEST.tar.bz2, so I plan to use this as the download source.
>>>>>> This bit is wrong - I need to use the .tar.bz within the .zip.
>>>>>> 
>>>>>>>> So far I have a recipe which downloads from this URL and extracts the files into the work area and ${WORKAREA}/drivers/media includes a Makefile and Kconfig.
>>>>>>>> 
>>>>>>>> I've looked at the Yocto documentation, but this doesn't seem to be a good match for the "Out of tree" kernel module case.
>>>>>>> Hmm. At a glance, I'd say that it does sound like a typical out of
>>>>>>> tree module build.
>>>>>> Ah, ok - to my (untrained) eye the use-case looked completely different based on the example.
>>>>>> 
>>>>>>> Did you try adopting the meta-skeleton hello-mod recipe and point it
>>>>>>> at that source directory ?
>>>>>> I have now (with the above change). However, it looks as if something within the build is referencing the host file system when building.
>>>>>> 
>>>>>> I'm building for ValleyIsland 32-bit:
>>>>>> 
>>>>>>  1) If I configure the drivers for 32-bit there is a linker error complaining that elf 32 and elf 64 aren't compatible (host is 64 bit);
>>>>> Hmm. The target arch should be used for this build. Are you enabling a
>>>>> multi lib config
>>>>> as well ?
>>>> Not that I know of ;-)
>>>> 
>>>> The build uses a .version file to specify the kernel. The top makefile creates this using 'uname -r' by default. I can run 'make dir DIR="..." in do_configure() to specify the path to the yocto kernel files, which seems to fix this (after modifying another makefile, which prepends "../" to the DIR path).
>>> 
>>> Definite host contamination there. You likely want the code, but
>>> not the build infrastructure in this case.
>>> 
>>>> 
>>>>>  2) Everything appears to build if I target 64-bit, but the installer tries to modify /lib/modules/3.2.0-67/..., which is also part of the host.
>>>>> 
>>>>> Do the Makefile's that come in that archive (I haven't gone to look)
>>>>> have a custom
>>>>> install rule ? If so, that's likely the problem. If the kernel's build
>>>>> system is triggered
>>>>> (i.e. the makefile follows the conventions), everything will be
>>>>> installed to the proper
>>>>> location.
>>>> The installer uses DESTDIR to select the installation path - I've not worked out how this gets set yet or how I can set it from within my recipe.
>>>> 
>>>> Is there a trick I can use to get the kernel's build system to manage things?
>>> 
>>> In this case, you really need to replace (or patch) the existing Makefile
>>> that comes with the package.
>>> 
>>> The hello-mod example I pointed out has makefile that shows the right
>>> definitions to allow the kernel's build system to enter the directory, build
>>> and install the modules.
>> 
>> I've made some good progress, but still not quite there.
>> 
>> I've got a do_compile() that basically does:
>> 
>>   make DIR=${STAGING_KERNEL_DIR}
>> 
>> The appears to build the modules correctly - testing will tell ;-)
>> 
>> I've then got similar in do_install():
>> 
>>   make DIR=${STAGING_KERNEL_DIR} DESTDIR=${D}
>> 
>> That's 99% there - the modules get put in image/lib/modules/3.10.40-ltsi/...
>> They should be in image/lib/modules/3.10.40-ltsi-yocto-standard/... - not sure yet how to fix this one.
>> 
> 
> The kernel-abiversion should have all the details to get the mdoules
> installed in the right place. See the use of the file in the various
> module bbclasses.
> 
> export KERNEL_VERSION = "${@base_read_file('${STAGING_KERNEL_DIR}/kernel-abiversion')}"

Thanks, that helps. Looks like I need to find a bug in the makefiles now - using kernel-abiversion results in a message reporting that 3.10.40-ltsi-yocto-standard will be used, but the installation ends up going to 3.0.40-ltsi-yocto-standard :-(

> 
> Bruce
> 
>> There is also a packaging QA issue causing a build failure (some files aren't used), but an INSANE_SKIP installed-vs-shipped fixes that one for now.
>> 
>> --
>> 
>> Chris Tapp
>> opensource at keylevel.com
>> www.keylevel.com

--

Chris Tapp
opensource at keylevel.com
www.keylevel.com