Re: [PATCH v2 0/2] iio: humidity: si7020: Check device property for skipping reset in probe

From: Jonathan Cameron
Date: Thu May 12 2022 - 12:49:12 EST


On Thu, 12 May 2022 11:20:18 -0500
Eddie James <eajames@xxxxxxxxxxxxx> wrote:

> I2C commands issued after the SI7020 is starting up or after reset
> can potentially upset the startup sequence. Therefore, the host
> needs to wait for the startup sequence to finish before issuing
> further i2c commands. This is impractical in cases where the SI7020
> is on a shared bus or behind a mux, which may switch channels at
> any time (generating I2C traffic). Therefore, check for a device
> property that indicates that the driver should skip resetting the
> device when probing.

Why not lock the bus? It's not ideal, but then not resetting and hence
potentially ending up in an unknown state isn't great either.

Jonathan

>
> Changes since v1:
> - Fix dt binding document
>
> Eddie James (2):
> dt-bindings: iio: humidity: Add si7020 bindings
> iio: humidity: si7020: Check device property for skipping reset in probe
>
> .../bindings/iio/humidity/silabs,si7020.yaml | 47 +++++++++++++++++++
> .../devicetree/bindings/trivial-devices.yaml | 2 -
> drivers/iio/humidity/si7020.c | 14 +++---
> 3 files changed, 55 insertions(+), 8 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/iio/humidity/silabs,si7020.yaml
>