| Message ID | 20240514-ad4111-v2-0-29be6a55efb5@analog.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | Add support for AD411x | expand |
On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay <devnull+dumitru.ceclan.analog.com@kernel.org> wrote: > > This patch series adds support for the Analog Devices AD4111, AD4112, > AD4114, AD4115, AD4116 within the existing AD7173 driver. > It looks like most of the patches in this series are cleanups and fixes of the existing driver unrelated to adding AD411x. Perhaps it would be better to split those out into a separate series so we can focus on that first? Especially since several of them need to be sent as fixes for the v6.10 kernel to avoid breaking usespace or bindings in the next release.
On 16/05/2024 01:35, David Lechner wrote: > On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay > <devnull+dumitru.ceclan.analog.com@kernel.org> wrote: >> >> This patch series adds support for the Analog Devices AD4111, AD4112, >> AD4114, AD4115, AD4116 within the existing AD7173 driver. >> > > It looks like most of the patches in this series are cleanups and > fixes of the existing driver unrelated to adding AD411x. Perhaps it > would be better to split those out into a separate series so we can > focus on that first? Especially since several of them need to be sent > as fixes for the v6.10 kernel to avoid breaking usespace or bindings > in the next release. Sure
This patch series adds support for the Analog Devices AD4111, AD4112, AD4114, AD4115, AD4116 within the existing AD7173 driver. The AD411X family encompasses a series of low power, low noise, 24-bit, sigma-delta analog-to-digital converters that offer a versatile range of specifications. They integrate an analog front end suitable for processing fully differential/single-ended and bipolar voltage inputs. Particularities of the models: - All ADCs have inputs with a precision voltage divider with a division ratio of 10. - AD4116 has 5 low level inputs without a voltage divider. - AD4111 and AD4112 support current inputs (0 mA to 20 mA) using a 50ohm shunt resistor. Discussions from this patch series have concluded with: -Datasheets mention single-ended and pseudo differential capabilities by the means of connecting the negative input of a differential pair (IN-) to a constant voltage supply and letting the positive input fluctuate. This is not a special operating mode, it is a capability of the differential channels to also measure such signals. -Single-ended and pseudo differential do not need any specific configuration and cannot be differentiated from differential usage by the driver side => offer adi,channel-type attribute to flag the usage of the channel -VINCOM is described as a dedicated pin for single-ended channels but as seen in AD4116, it is a normal input connected to the cross-point multiplexer (VIN10, VINCOM (single-ended or differential pair)). This does not mean full functionality in any configuration: AD4111:"If any two voltage inputs are paired in a configuration other than what is described in this data sheet, the accuracy of the device cannot be guaranteed". -ADCIN15 input pin from AD4116 is specified as the dedicated pin for pseudo-differential but from the datasheet it results that this pin is also able to measure single-ended and fully differential channels ("ADCIN11, ADCIN15. (pseudo differential or differential pair)"; "An example is to connect the ADCIN15 pin externally to the AVSS pin in a single-ended configuration") As such, detecting the type of usage of a channel is not possible and will be the responsability of the user to specify. If the user has connected a non 0V (in regards to AVSS) supply to the negative input pin of a channel in a pseudo differential configuration, the offset of the measurement from AVSS will not be known from the driver and will need to be measured by other means. Datasheets: https://www.analog.com/media/en/technical-documentation/data-sheets/AD4111.pdf https://www.analog.com/media/en/technical-documentation/data-sheets/AD4112.pdf https://www.analog.com/media/en/technical-documentation/data-sheets/AD4114.pdf https://www.analog.com/media/en/technical-documentation/data-sheets/AD4115.pdf https://www.analog.com/media/en/technical-documentation/data-sheets/AD4116.pdf This series depends on patch: (iio: adc: ad7173: Use device_for_each_child_node_scoped() to simplify error paths.) https://lore.kernel.org/all/20240330190849.1321065-6-jic23@kernel.org Signed-off-by: Dumitru Ceclan <mitrutzceclan@gmail.com> --- Changes in v2: dt-bindings: adc: ad7173: add support for ad411x - Add constraint for missing avdd2-supply on ad411x - Change support for current channels to selecting the actual diff-channels input values and activating the adi,current-channel property - Add constraint for adi,current-channel - Add adi,channel-type to be able to differentiante in the driver between single-ended, pseudo-differential and differential channels. - Update diff-channels description to decribe inputs beside the AINs iio: adc: ad7173: fix buffers enablement for ad7176-2 - Specify ".has_input_buf = false" for AD7176-2 - Drop fixes tag, specify that configuration bits are read only iio: adc: ad7173: refactor channel configuration parsing - Add Link and Suggested-by in commit message iio: adc: ad7173: refactor ain and vref selection - Improve commit message to express commit purpose - Refactor line wrappings due to reduced indent - Change AINs check to a loop iio: adc: ad7173: add support for special inputs - Create patch iio: adc: ad7173: Add ad7173_device_info names - Create patch iio: adc: ad7173: Remove index from temp channel - Justify in commit message userspace breakage - Remove index from the correct channel template iio: adc: ad7173: Add support for AD411x devices - Add missing validation for VCOM and inputs with voltage divider - Add missing validation for AD4116 low level inputs - Add missing ad7173_device_info names - Add support for setting differential flag depending on the channel type - Change current channel validation to use actual pin values - Combine multiple chipID reg values in a single define (AD7173_AD4111_AD4112_AD4114_ID) - Rename num_inputs and num_inputs_with_divider to include voltage - Add comment to specify that num_voltage_inputs_with_divider does not include the VCOM pin. - Change break to direct returns where possible in switch cases - Add fix for ad411x gpio's iio: adc: ad7173: Reduce device info struct size - Create patch - Link to v1: https://lore.kernel.org/r/20240401-ad4111-v1-0-34618a9cc502@analog.com --- Dumitru Ceclan (9): dt-bindings: adc: ad7173: add support for ad411x iio: adc: ad7173: fix buffers enablement for ad7176-2 iio: adc: ad7173: refactor channel configuration parsing iio: adc: ad7173: refactor ain and vref selection iio: adc: ad7173: add support for special inputs iio: adc: ad7173: Add ad7173_device_info names iio: adc: ad7173: Remove index from temp channel iio: adc: ad7173: Add support for AD411x devices iio: adc: ad7173: Reduce device info struct size .../devicetree/bindings/iio/adc/adi,ad7173.yaml | 118 +++++- drivers/iio/adc/ad7173.c | 438 ++++++++++++++++++--- 2 files changed, 497 insertions(+), 59 deletions(-) --- base-commit: 5ab61121a34759eb2418977f0b3589b7edc57776 change-id: 20240312-ad4111-7eeb34eb4a5f Best regards,