DMA and I2S driver/DT changes between Busta and Stretch
Nobody has claimed this yet.
Assessment
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Newbie friendliness
- 25/100
- Issue type
- Bug
- Clarity
- Needs clarification
- Activity status
- Stale
- Tech stack
- c
- Domain
- embedded-iot, operating-systems
Research direction
Start by comparing the bcm2835-i2s.c versions used by Buster and Stretch, then review the DMA-related setup for Raspberry Pi 4. Reproduce the channel remapping with the linked ALSAFullDuplexTest.C and ch=8; done means identifying the relevant driver or device-tree difference and documenting a confirmed cause.
Written by the indexing model from the issue text.
Description
A user has tested I2S differences between stretch and busta w.r.t. mutlichannel audio :
https://github.com/Audio-Injector/Octo/issues/20
The user tests a modified ALSAFullDuplexTest.C file from here with the variable ch=8 :
https://github.com/flatmax/gtkiostream/blob/master/test/ALSAFullDuplexTest.C
They compile it with :
g++ -o ALSAFullDuplexTest ALSAFullDuplexTest.C 'pkg-config --cflags --libs gtkIOStream'
On Busta it works as expected channels are not remapped. On Stretch channels are remapped randomly between executions. Only rebooting changes that behaviour.
Reported for a Pi 4.
Is it possible to link to the different bcm2835-i2s.c files which are used in Busta and Stretch ?
It is also possible that something has changed w.r.t. DMA setup.
- Dominant language
- C
- Stars
- 13.2k
- Forks
- 5.5k
- Avg merge
- 2d 21h
- Merged PRs (30d)
- 21
Contributor guide
No contributing guide indexed for this repository
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
More from raspberrypi/linux
-
Difficulty 2/5 1-3 hours Newbie friendliness 68/100
raspberrypi/linux#7415 · 2 comments · 1 reaction ·
-
rp1-cfe doesn't forward V4L2_EVENT_SOURCE_CHANGE event from csi-2 sensor driver to userspace app Open
Difficulty 2/5 1-3 hours Newbie friendliness 72/100
raspberrypi/linux#7399 · 1 comment ·
-
Difficulty 1/5 Under an hour Newbie friendliness 82/100
raspberrypi/linux#7357 · 1 comment ·
-
Difficulty 2/5 1-3 hours Newbie friendliness 68/100
raspberrypi/linux#7054 · 2 comments ·
-
Difficulty 4/5 3-5 days Newbie friendliness 48/100
raspberrypi/linux#7634 · 8 comments · 1 reaction ·
All issues in raspberrypi/linux
Similar issues
-
Difficulty 2/5 1-3 hours Newbie friendliness 88/100
zephyrproject-rtos/zephyr#119726 ·
-
[Bounty proposal] fix(web): memory insights count an evening memory on the next day ($25 proposed) Open
Difficulty 2/5 1-3 hours Newbie friendliness 84/100
BasedHardware/omi#15320 ·
-
[adam] AdamNet network read doesn't cap to MAX_ADAM_PACKET_LEN, overflows client receive buffers Open
Difficulty 2/5 1-3 hours Newbie friendliness 88/100
FujiNetWIFI/fujinet-firmware#1649 · 2 comments ·
-
Difficulty 2/5 1-3 hours Newbie friendliness 68/100
HarbourMasters/Shipwright#7229 ·
-
Difficulty 2/5 1-3 hours Newbie friendliness 72/100
riscv-software-src/riscv-isa-sim#2435 · 1 comment ·