On Mon, 10 Mar 2025 10:46:45 +0200 Matti Vaittinen <mazziesaccount@xxxxxxxxx> wrote: > On 08/03/2025 18:44, Jonathan Cameron wrote: > > On Mon, 3 Mar 2025 13:33:39 +0200 > > Matti Vaittinen <mazziesaccount@xxxxxxxxx> wrote: > > > >> The ROHM BD79124 is a 12-bit, 8-channel, SAR ADC. The ADC supports > >> an automatic measurement mode, with an alarm interrupt for out-of-window > >> measurements. The window is configurable for each channel. > >> > >> The I2C protocol for manual start of the measurement and data reading is > >> somewhat peculiar. It requires the master to do clock stretching after > >> sending the I2C slave-address until the slave has captured the data. > >> Needless to say this is not well suopported by the I2C controllers. > >> > >> Thus the driver does not support the BD79124's manual measurement mode > >> but implements the measurements using automatic measurement mode relying > >> on the BD79124's ability of storing latest measurements into register. > >> > >> The driver does also support configuring the threshold events for > >> detecting the out-of-window events. > >> > >> The BD79124 keeps asserting IRQ for as long as the measured voltage is > >> out of the configured window. Thus the driver masks the received event > >> for a fixed duration (1 second) when an event is handled. This prevents > >> the user-space from choking on the events > >> > >> The ADC input pins can be also configured as general purpose outputs. > >> Those pins which don't have corresponding ADC channel node in the > >> device-tree will be controllable as GPO. > >> > >> Signed-off-by: Matti Vaittinen <mazziesaccount@xxxxxxxxx> > > Hi Matti > > > > Just a few really trivial comments. If all else in the > > set was resolved I'd probably have applied with a tweak or two > > > > Thanks, > > > > Jonathan > > > >> obj-$(CONFIG_SC27XX_ADC) += sc27xx_adc.o > >> diff --git a/drivers/iio/adc/rohm-bd79124.c b/drivers/iio/adc/rohm-bd79124.c > >> new file mode 100644 > >> index 000000000000..466c7decf8fc > >> --- /dev/null > >> +++ b/drivers/iio/adc/rohm-bd79124.c > >> @@ -0,0 +1,1108 @@ > > ... > > > >> + > >> +/* Read-only regs */ > > > > Given naming this is pretty obvious. > > I would drop the comment > > I will drop this, although I am not sure it is as self explatonary as > one thinks. I've seen people getting this wrong because the logic of > regmap-ranges is kind of reversed. (Eg, read-only is done by adding > range to wr_tables and not to rd_tables - as a no-range). It's obvious in the structure naming + how it is used. I agree the interface in general is non obvious. Jonathan > > Thanks for the review, and rest of the comments just agreed with. > > -- Matti
