Re: [RESEND v6,2/3] i2c: mux: pca954x: support property idle-state

From: Peter Rosin
Date: Fri Jan 03 2020 - 09:06:21 EST

On 2019-12-25 11:36, Biwen Li wrote:
> This supports property idle-state,if present,
> overrides i2c-mux-idle-disconnect.
> My use cases:
> - Use the property idle-state to fix
> an errata on LS2085ARDB and LS2088ARDB.
> - Errata id: E-00013(board LS2085ARDB and
> LS2088ARDB revision on Rev.B, Rev.C and Rev.D).
> - About E-00013:
> - Description: I2C1 and I2C3 buses
> are missing pull-up.
> - Impact: When the PCA954x device is tri-stated, the I2C bus
> will float. This makes the I2C bus and its associated
> downstream devices inaccessible.
> - Hardware fix: Populate resistors R189 and R190 for I2C1
> and resistors R228 and R229 for I2C3.
> - Software fix: Remove the tri-state option from the PCA954x
> driver(PCA954x always on enable status, specify a
> channel zero in dts to fix the errata E-00013).
> Tested-by: Ioana Ciornei <ioana.ciornei@xxxxxxx>
> Signed-off-by: Biwen Li <>

Pushed to i2c-mux/for-next with some minor language tweaks.