Messages in this thread | | | Date | Tue, 28 Nov 2017 09:01:42 -0600 | From | Rob Herring <> | Subject | Re: [PATCH v2 1/2] hwmon: (jc42) optionally try to disable the SMBUS timeout |
| |
On Mon, Nov 27, 2017 at 05:31:00PM +0100, Peter Rosin wrote: > With a nxp,se97 chip on an atmel sama5d31 board, the I2C adapter driver > is not always capable of avoiding the 25-35 ms timeout as specified by > the SMBUS protocol. This may cause silent corruption of the last bit of > any transfer, e.g. a one is read instead of a zero if the sensor chip > times out. This also affects the eeprom half of the nxp-se97 chip, where > this silent corruption was originally noticed. Other I2C adapters probably > suffer similar issues, e.g. bit-banging comes to mind as risky... > > The SMBUS register in the nxp chip is not a standard Jedec register, but > it is not special to the nxp chips either, at least the atmel chips > have the same mechanism. Therefore, do not special case this on the > manufacturer, it is opt-in via the device property anyway. > > Signed-off-by: Peter Rosin <peda@axentia.se> > --- > Documentation/devicetree/bindings/hwmon/jc42.txt | 4 ++++
Acked-by: Rob Herring <robh@kernel.org>
> drivers/hwmon/jc42.c | 21 +++++++++++++++++++++ > 2 files changed, 25 insertions(+)
| |