On 13/11/2025 17:30, David Heidelberg via B4 Relay wrote:
With the growing popularity of running upstream Linux on mobile devices,
we're beginning to run into more and more edgecases. The OnePlus 6 is a
fairly well supported 2018 era smartphone, selling over a million units
in it's first 22 days. With this level of popularity, it's almost
inevitable that we get third party replacement displays, and as a
result, replacement touchscreen controllers.
The OnePlus 6 shipped with an extremely usecase specific touchscreen
driver, it implemented only the bare minimum parts of the highly generic
rmi4 protocol, instead hardcoding most of the register addresses.
As a result, the third party touchscreen controllers that are often
found in replacement screens, implement only the registers that the
downstream driver reads from. They additionally have other restrictions
such as heavy penalties on unaligned reads.
This series attempts to implement the necessary workaround to support
some of these chips with the rmi4 driver. Although it's worth noting
that at the time of writing there are other unofficial controllers in
the wild that don't work even with these patches.
We have been shipping these patches in postmarketOS for the last several
years, and they are known to not cause any regressions on the OnePlus
6/6T (with the official Synaptics controller), however I don't own any
other rmi4 hardware to further validate this.
The series is also available (until merged) at
https://gitlab.com/sdm845/sdm845-next/-/commits/b4/synaptics-rmi4
---
Changes in v6:
- Rebased on top of next-20251113.
- No other change since the Rob Herring comment.
- Link to v5:
https://lore.kernel.org/r/[email protected]
[...]
Hello Dmitry,
May I ask whether this series will make it into 6.19?
I realize it may be unlikely, but I’m beginning to feel that this series
is being overlooked. I’m very willing to improve it and help make the
mainline experience better, but I can’t do so without any feedback.
Since Rob indicated that this approach appears to be the right
direction, please let me know if there is anything I can do to move it
forward.
Thank you,
David
