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August 2024, 10:53:16 CEST schrieb Carlos Song: > > -----Original Message----- > > From: Alexander Stein > > Sent: Thursday, August 29, 2024 6:55 PM > > To: Aisheng Dong ; andi.shyti@kernel.org; > > shawnguo@kernel.org; s.hauer@pengutronix.de; kernel@pengutronix.de; > > festevam@gmail.com; linux-arm-kernel@lists.infradead.org > > Cc: linux-i2c@vger.kernel.org; imx@lists.linux.dev; > > linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org; Car= los Song > > > > Subject: [EXT] Re: [PATCH 5/5] i2c: imx-lpi2c: increase PM timeout to a= void > > operate clk frequently > > > > Caution: This is an external email. Please take care when clicking link= s or > > opening attachments. When in doubt, report the message using the 'Repor= t this > > email' button > > > > > > Hi, > > > > Am Donnerstag, 29. August 2024, 11:37:22 CEST schrieb carlos.song@nxp.c= om: > > > From: Clark Wang > > > > > > Switching the clock frequently will affect the data transmission > > > efficiency, and prolong the timeout to reduce autosuspend times for > > > lpi2c. > > > > Efficiency as in throughput or total time per transfer? Do you have any= numbers? > > >=20 > Hi, Thank your for your quick ack! >=20 > Apologies for the unclear explanation. The efficiency I'm referring to is= n't just for I2C. For platforms with SC firmware > like the 8X series, every i2c transfer to enable or disable the clock not= ifies the SC firmware to perform a clock operation. > So if the autosuspend time is short, i2c may enable and disable clock fre= quently, it will occupy resources of the SC firmware. >=20 > Therefore, we add this patch to minimize the excessive sc firmware resour= ce waste caused by frequent I2C clock enable/disable operations. Thanks for the explanation. So this delay only occurs on systems using an S= C (imx8qm/qxp) or SM (imx95), right? Is there a chance to detect this kind of clock provider and make this timeo= ut configurable? Best regards, Alexander =2D-=20 TQ-Systems GmbH | M=FChlstra=DFe 2, Gut Delling | 82229 Seefeld, Germany Amtsgericht M=FCnchen, HRB 105018 Gesch=E4ftsf=FChrer: Detlef Schneider, R=FCdiger Stahl, Stefan Schneider http://www.tq-group.com/