Hello Jonathan for the explanation, the chip variants at reset have a FIFO restricted to 512 bytes like the original one. You have to write specific bits in a register to unlock the FIFO to its full size. The driver is writing these bits only when you configure the variant. Otherwise, it will behave really like the original one. That's why I call them fully compatible. Thanks, JB ________________________________________ From: Jonathan Cameron <jic23@xxxxxxxxxx> Sent: Saturday, September 28, 2024 18:45 To: Krzysztof Kozlowski <krzk@xxxxxxxxxx> Cc: Jean-Baptiste Maneyrol <Jean-Baptiste.Maneyrol@xxxxxxx>; Lars-Peter Clausen <lars@xxxxxxxxxx>; Rob Herring <robh@xxxxxxxxxx>; Krzysztof Kozlowski <krzk+dt@xxxxxxxxxx>; Conor Dooley <conor+dt@xxxxxxxxxx>; Jean-Baptiste Maneyrol <Jean-Baptiste.Maneyrol@xxxxxxx>; linux-iio@xxxxxxxxxxxxxxx <linux-iio@xxxxxxxxxxxxxxx>; devicetree@xxxxxxxxxxxxxxx <devicetree@xxxxxxxxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx <linux-kernel@xxxxxxxxxxxxxxx> Subject: Re: [PATCH v2 1/2] dt-bindings: iio: imu: mpu6050: Add iam20680ht/hp bindings to mpu6050 This Message Is From an External Sender This message came from outside your organization. On Mon, 23 Sep 2024 17:38:44 +0200 Krzysztof Kozlowski <krzk@xxxxxxxxxx> wrote: > On 23/09/2024 16:53, Jean-Baptiste Maneyrol via B4 Relay wrote: > > From: Jean-Baptiste Maneyrol <jean-baptiste.maneyrol@xxxxxxx> > > > > IAM-20680HT & HP are 2 variants of IAM-20680 fully compatible. > > They just have better specs, temperature range and a bigger FIFO. > > > > Signed-off-by: Jean-Baptiste Maneyrol <jean-baptiste.maneyrol@xxxxxxx> > > --- > > Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> Ah. I missed v2 as checked by email address. As per v1 review I've tweaked this patch description to say they are backwards compatible rather than fully (as the fifo size is not discoverable) Jonathan > > Best regards, > Krzysztof >