Audio and HDMI port not working on Jessie

[Giuseppe Longo <giuseppelng@gmail.com>]

Hello,
I've just installed Jessie on my Laptop (Dell inspiron 5000 Series)
and unfortunally
audio card and hdmi port are not working.

Regarding hdmi port, from lspci I see:
00:02.0 VGA compatible controller: Intel Corporation Device 1916 (rev 07)
01:00.0 Display controller: Advanced Micro Devices, Inc. [AMD/ATI] Sun
XT [Radeon HD 8670A/8670M/8690M] (rev 81)

>From dmesg I see the following error message:
[   15.064289] [drm] radeon kernel modesetting enabled.
[   15.064330] [drm:radeon_pci_probe] *ERROR* radeon kernel
modesetting for R600 or later requires firmware-linux-nonfree.

Instead regarding the audio, I've made all checks that dpkg bot suggested:
- user is in audio grou
- unmute channels
- speakers are on
- pulseaudio is started

I have no idea how to fix these issues,
Please, any help and advice is appreciated.

Thanks