Re: [PATCH v2 0/2] ic2: mux: pca9541: add delayed-release support

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 2/28/22 09:11, Zev Weiss wrote:
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?


The i2c/i2c-mux maintainers will need to accept it, and you'll need
approval for the DT changes from a DT maintainer (presumably Rob).

Guenter



[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux