Michael,
On 09/21/2015 06:27 PM, Michael Welling wrote:
On Mon, Sep 21, 2015 at 06:04:36PM -0700, Guenter Roeck wrote:
Hi Michael,
On 09/21/2015 03:06 PM, Michael Welling wrote:
I am in the process of starting a new device driver for the ADS1018 ADC.
Before starting I did some research as whether similar drivers exist in the kernel.
It appears that ADC drivers are in both hwmon and iio/adc. The closest drivers to
the device mentioned are in hwmon.
Where is the best place for this new ADC driver?
Your call. You could add support for the chip to hwmon/ads1015.c, or you could write
a new driver in iio/adc. If you do the latter, maybe you can also include support
for ads1015 and ads1115, so we can ultimately remove the ads1015 driver from hwmon.
Guenter,
Though the iio route may be more work I have a feeling the
driver will be better off there. The use of regmap support
should allow for both the SPI and I2C version to coexist.
Sorry, you lost me. There is no correlation between iio/hwmon and regmap.
regmap can be (and is) used with both subsystems. Please clarify.
I will try my best to implement the driver in a way that
can cover these other I2C devices mentioned.
Shouldn't ADCs all be in the same subsystem?
Has there been any effort to unify or distiguish where drivers should go?
In general, ADCs primarily used for the purpose of ADC measurements would go
into iio, and ADCs used primarily for hardware monitoring would go into hwmon.
There are no strict rules, though, and this is not always black-and-white.
I am sure there are some drivers in hwmon which would be better suited for iio.
Primarily that would be the case because the iio subsystem is relatively new,
and such drivers did not have a home other than hwmon until a couple of years ago.
If you find any drivers in hwmon which you think should be moved, please feel free
to do the conversion.
Has anyone considered an alternative implementation for generic ADCs?
I was thinking about an implementation similar to gpiolib whereas ADCs can be
resources for other drivers.
For instance, ADC lines could be registered to a joystick driver and used to provide
analog stick or pressure sensitive button. Another example could be registering analog
lines for an analog accelerometer driver.
Is this a bad idea?
I am quite sure that is possible. If it isn't currently supported, it waits for someone
with a use case to implement it.
Guenter
--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
