Re: [PATCH v2 06/19] i2c: designware_i2c: Use an accurate bus clock instead of MHz

Hello Simon,

Am 03.01.2020 um 23:26 schrieb Simon Glass:

At present the driver uses an approximation for the bus clock, e.g. 166MHz instead of 166 2/3 MHz.

This can result in small errors in the resulting I2C speed, perhaps 0.5% or so.

Adjust the existing code to start from the accurate figure, even if later rounding reduces this accuracy.

Update the bus speed code to work in KHz instead of MHz, which removes most of the error.

Signed-off-by: Simon Glass sjg@chromium.org

Changes in v2: None

drivers/i2c/designware_i2c.c | 18 ++++++++---------- drivers/i2c/designware_i2c.h | 4 ++-- 2 files changed, 10 insertions(+), 12 deletions(-)

Reviewed-by: Heiko Schocher hs@denx.de

bye, Heiko