Re: [PATCH 0/2] iio: adc: add TI ADS1299

[Andy Shevchenko]

On Sun, Oct 18, 2026 at 09:12:45PM -0300, Stephan Costa Barros wrote:
> This series adds a driver for the TI ADS1299 family (ADS1299, ADS1299-6
> and ADS1299-4): 24-bit, simultaneous-sampling biopotential front-ends
> for EEG, on SPI.

Why a brand new driver?

> This first version keeps to the generic IIO ABI: raw reads, the gain of
> each channel's PGA through its scale, the sampling frequency, and a
> kfifo buffer fed from the DRDY interrupt with a software timestamp.
> 
> The part has more, which I would like to add in follow-up series, each
> with its own ABI discussion: SRB1 and SRB2 reference routing, the bias
> drive amplifier, lead-off detection (through IIO_EV_TYPE_FAULT and
> IIO_EV_DIR_FAULT_OPENWIRE), the internal test signal, the temperature
> sensor and supply monitors, GPIO1 to GPIO4 as a gpiochip, the CLK pin
> as a clock output, and daisy chains. The binding already describes the
> hardware for those.
> 
> A question on structure. The driver started from ti-ads1298.c, and in
> this subset the two are close. What differs here is the PGA gain table
> (1 to 24 against 1 to 12 with 3), the data rates (no high-resolution
> mode), the fixed 4.5 V internal reference, the ID register layout and
> the 4 and 6 channel variants; above 0x14 the register maps also part
> (MISC1 and MISC2 here, PACE, RESP and WCT on the ADS1298). Most of what
> would follow, SRB1 and SRB2, the bias drive and lead-off on every
> channel, is specific to the ADS1299, so I kept a separate driver. If you
> would rather have the ADS1299 as a variant in ti-ads1298, I can rework
> it that way.

Okay, I think you can try to rework this as a series on top of the existing
code. I can't easily see if the above difference warrants a brand new driver.

-- 
With Best Regards,
Andy Shevchenko