Re: [PATCH 0/2] Add support for Microchip EMC1812

Hi Guenter,

Thank you for the feedback.

On Tue, 2025-09-23 at 19:11 -0700, Guenter Roeck wrote:

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On 9/20/25 04:33, Jonathan Cameron wrote:

quoted

On Wed, 17 Sep 2025 15:21:56 +0300
Marius Cristea [off-list ref] wrote:

quoted

This is the iio driver for EMC1812/13/14/15/33 multichannel Low-
Voltage
Remote Diode Sensor Family. The chips in the family have one
internal
and different numbers of external channels, ranging from 1
(EMC1812) to
4 channels (EMC1815).
Reading diodes in anti-parallel connection is supported by
EMC1814, EMC1815
and EMC1833.

Current version of driver does not support interrupts, events and
data
buffering.

Hi Marius,

For a temperature monitoring device like this, the opening question
is
always why not HWMON?

There are various reasons we have temp sensors in IIO but mostly
they are not
described as being monitors and this one is.

IIO may well be the right choice for this part, but good to lay out
your
reasoning and +CC the hwmon list and maintainers.  There is an
emc1403
driver already in hwmon, so perhaps compare and contrast with that.

I've +CC Jean, Guenter and list to save sending a v2 just to do
that.

At first glance it looks like the series is (mostly ?) register
compatible
to the chips supported by the emc1403 driver, so it should be
straightforward
to add support for the emc180x series to that driver.

Guenter

Most of the register address are compatible. The EMC181X is an update 
(a newer generation) then the EMC1403.

The biggest improvement is that the EMC18XX has a continuous block of
registers in order to improve the temperature reading (that means some
addresses are overlapping with the older register maps) and a new set
of registers to  handle the "Rate Of Change" functionality.
Also the older EMC14XX has some hardcoded configuration/features based
on the part number.

Considering all of the above I consider that the complexity of the
EMC1403 will increase quite a lot without any real benefit and it will
be harder to be maintained.

I have submitted this as the fist iteration from a longer list of
feature that I want to add to the driver, including events and maybe
interrupts.

If nobody has anything against, I would like to add a separate driver
for EMC18XX into the IIO.

Thanks and Best Regards,
Marius