This series adds a missing feature in the veml6070 driver to select the integration time, which also depends on an external restistor that has been added to the corresponding bindings. The datasheet provides a Refresh time vs Rset graph (figure 7), which does not clearly specify the minimum and maximum values for Rset. The manufacuter has confirmed that no values under 75 kohms should be used to keep linearity, and the graph does not go beyond 1200 kohms, which is also the biggest Rset used in the application note. The default value of 270 kohms is the one currently used in the driver to calculate the UVI. Signed-off-by: Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx> --- Changes in v4: - Add vendor prefix to rset-ohms property (bindings and driver). - Drop default values for out-of-range rset and fail the probe instead. - Link to v3: https://lore.kernel.org/r/20241028-veml6070-integration-time-v3-0-dd7ace62f480@xxxxxxxxx Changes in v3: - veml6075.yaml: simplify property handling (describe it completely at the top and add block for the devices that do not support it). - veml6070.c: use int instead of u32 for the integration times. - veml6070.c: refactor default rset value assignment. - veml6070.c: drop comment about default Rset and IT. - veml6070.c: use units from units.h - Link to v2: https://lore.kernel.org/r/20241024-veml6070-integration-time-v2-0-d53272ec0feb@xxxxxxxxx Changes in v2: - Rebase onto iio/testing and drop applied patches. - veml6075.yaml: use documented -ohms, top-level definition and per-device restriction. - veml6075.yaml: add default value. - veml6075.yaml: fix typo in commit message. - veml6070.c: adjust rset property name and convert from ohms to kohms to avoid overflows and work with the same units as in the datasheet. - veml6070.c: change default to 270 kohms (already used as default value to calculate UVI). - veml6070.c: calculate UVI according to the current integration time. - veml6070.c: re-calculate measurement time (i.e. msleep()) with the current integration time. - Link to v1: https://lore.kernel.org/r/20241017-veml6070-integration-time-v1-0-3507d17d562a@xxxxxxxxx --- Javier Carrasco (2): dt-bindings: iio: light: veml6075: document vishay,rset-ohms iio: light: veml6070: add support for integration time .../bindings/iio/light/vishay,veml6075.yaml | 18 +++ drivers/iio/light/veml6070.c | 131 +++++++++++++++++++-- 2 files changed, 141 insertions(+), 8 deletions(-) --- base-commit: e2687d0723257db5025a4cf8cefbd80bed1e2681 change-id: 20241014-veml6070-integration-time-78daf4eaad2f Best regards, -- Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx>
