On 09/10/2020 01:52, Douglas Anderson wrote:
Previously I landed commit 02b9aec59243 ("i2c: i2c-qcom-geni: Fix DMA
transfer race") to fix a race we were seeing. While that most
definitely fixed the race we were seeing, it looks like it causes
problems in the TX path, which we didn't stress test until we started
trying to update firmware on devices.
Let's revert that patch and try another way: fix the original problem
by disabling the interrupts that aren't relevant to DMA transfers.
Now we can stress both TX and RX cases and see no problems. I also
can't find any place to put an msleep() that causes problems anymore.
Since this problem only affects i2c, I'm hoping for an Ack from Bjorn
and then all these patches can go through the i2c tree. However, if
maintainers want to work a different way out to land that's OK too.
These patches fix I2C DMA issues on SM8250 we were observing
Tested-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
--
With best wishes
Dmitry
