On Mon, Feb 28, 2022 at 05:57:27AM PST, Guenter Roeck wrote:
On 2/28/22 00:43, Zev Weiss wrote:
On Mon, Jan 31, 2022 at 04:18:08PM PST, Zev Weiss wrote:
Hello,
This series adds support for a new pca9541 device-tree property
("release-delay-us"), which delays releasing ownership of the bus
after a transaction for a configurable duration, anticipating that
another transaction may follow shortly. By avoiding a
release/reacquisition between transactions, this can provide a
substantial performance improvement for back-to-back operations -- on
a Delta AHE-50DC (ASPEED AST1250) system running OpenBMC with dozens
of LM25066 PMICs on PCA9541-arbitrated busses, a setting of 10000 (10
ms) reduces the median latency the psusensor daemon's hwmon sysfs file
reads from 2.28 ms to 0.99 ms (a 57% improvement).
Ping...Guenter, any thoughts on this?
It sounds reasonable to me, but I don't have access to hardware anymore
to test it, so I have no means to confirm that it actually works.
Ack, thanks. In that case, what's the path forward on getting changes
to this driver merged? I see sign-offs from Wolfram and Peter on the
last few commits that touched it -- any input from the i2c/i2c-mux
maintainers?
Zev
