[yocto] [meta-raspberrypi][PATCH] make sound work out of the box for raspberrypi2

[Gary Thomas]

On 2015-03-24 02:40, Alex J Lennon wrote:
>
>
> On 24/03/2015 09:21, Alex J Lennon wrote:
>>
>> On 24/03/2015 08:21, Andreas Müller wrote:
>>> On Tue, Mar 24, 2015 at 12:14 AM, Gary Thomas<gary at mlbassoc.com>  wrote:
>>>> On 2015-03-23 16:22, Andreas Müller wrote:
>>>>> On Mon, Mar 23, 2015 at 10:43 PM, Gary Thomas<gary at mlbassoc.com>  wrote:
>>>>>> On 2015-03-23 14:57, Andreas Müller wrote:
>>>>>>> On Mon, Mar 23, 2015 at 4:59 PM, Gary Thomas<gary at mlbassoc.com>  wrote:
>>>>>>>> On 2015-03-22 14:21, Andreas Müller wrote:
>>>>>>>>>
>>>>>>>>> Signed-off-by: Andreas Müller<schnitzeltony at googlemail.com>
>>>>>>>>> ---
>>>>>>>>>      ...-during-boot-by-compiling-SND_BCM2835-int.patch | 38
>>>>>>>>> ++++++++++++++++++++++
>>>>>>>>>      recipes-kernel/linux/linux-raspberrypi_3.18.bb     |  8 +++--
>>>>>>>>>      2 files changed, 43 insertions(+), 3 deletions(-)
>>>>>>>>>      create mode 100644
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> recipes-kernel/linux/linux-raspberrypi/0001-start-sound-during-boot-by-compiling-SND_BCM2835-int.patch
>>>>>>>>
>>>>>>>>
>>>>>>>> I tried this patch (which downloaded very strangely using Thunderbird)
>>>>>>>> and
>>>>>>>> the
>>>>>>>> kernel rebuilt fine.  I now have the audio detected, but still no sound
>>>>>>>> :-(
>>>>>>>> Again I've tried the internal (phono) speakers as well as HDMI audio.
>>>>>>>>
>>>>>>>> Just to prove a point on the [brand new] hardware, I installed OpenELEC
>>>>>>>> (XBMC)
>>>>>>>> and it works fine using the HDMI audio.  Sadly when I tried Raspbian
>>>>>>>> and
>>>>>>>> Ubuntu
>>>>>>>> there was no sound either...
>>>>>>>>
>>>>>>>> Were you (Andreas) able to get any sound with this patch?
>>>>>>>>
>>>>>>> Yes but I have used 3.5mm sound output - Should have mentioned that in
>>>>>>> commit. I guess there is to enable something else in kernel config for
>>>>>>> HDMI. Will look into that
>>>>>>
>>>>>> I've tried the 3.5mm jack as well but nothing seems to come out.
>>>>>> I even tried booting with the HDMI missing (powered off) in case
>>>>>> that was causing some confusion.
>>>>>>
>>>>>> Did you make any changes to config.txt to get this going?
>>>>> No
>>>>> Have my standard xfce-image with xfce4-mixer and as mentioned out of
>>>>> the box: I can hear sound / change volume...
>>>> Would it be possible to share your [bootable] image?
>>>>
>>>>> What does happen if you start alsamixer - if it is installed on your
>>>>> image?
>>>> alsamixer looks correct.
>>>>
>>>> BTW, I've tried this on my RaspberryPi Model B and I don't get any sound
>>>> from it either :-(  Again, booting with test_mode=1 shows that the hardware
>>>> is working, just not in Linux. I'm sure I've tried this in the past with
>>>> success so I'm becoming more and more confused...
>>>>
>>> For sharing I need to create a smaller image - the current one
>>> contains all stuff from meta-games, all browsers and more. Hope to get
>>> that done tomorrow evening. What is the preferred way of sharing huge
>>> files?
>>>
>> Circling around this a little, hello_audio built out of vc_graphics
>> works too over the audio jack
>>
>> Alex
>>
>
> OK I got some life from GStreamer and my RPIv2
>
> Install amixer
>
> modprobe snd_bcm2835 (or presumably use an image with audio built-in)
>
> amixer cset numid=3 1 (to set output to audio jack)
>
> gst-launch-1.0 audiotestsrc ! alsasink
>
> I get a tone out of the audio jack. So some kind of audio routing defaults issue.

Indeed, this does work - tested on RaspberryPi and RaspberryPi2.

Now, to figure out how to make audio over HDMI work.

-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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