On Mon, Nov 15, 2021 at 12:19:26PM +0200, Andy Shevchenko wrote: > On Mon, Nov 15, 2021 at 10:35:55AM +0100, Lawrence,Wang wrote: > > From: "Wang, Lawrence" <lawrence.wang@xxxxxxxxxxxxxxx> > > > > Current code support config the HCNT/LCNT only via ACPI method. for those > > platform that not support ACPI, will get the HCNT/LCNT value based on input > > clock. But it is not always accuracy. for example in some platform will get > > lower speed(320khz) in fast mode, and get faster speed(105khz/even more) in > > standard mode. > > > > This patch makes it possible for the non-ACPI platform to pass more optimal > > HCNT/LCNT values to the core driver via dts if they are known beforehand. > > If these are not set we use the calculated values. > > Besides the fact it misses DT schema update, why this is needed at all? > What's wrong with the existing DT timings? Just for your convenience an excerpt from Documentation/devicetree/bindings/i2c/i2c.txt - i2c-scl-falling-time-ns Number of nanoseconds the SCL signal takes to fall; t(f) in the I2C specification. - i2c-scl-internal-delay-ns Number of nanoseconds the IP core additionally needs to setup SCL. - i2c-scl-rising-time-ns Number of nanoseconds the SCL signal takes to rise; t(r) in the I2C specification. - i2c-sda-falling-time-ns Number of nanoseconds the SDA signal takes to fall; t(f) in the I2C specification. -- With Best Regards, Andy Shevchenko
