v1: https://lore.kernel.org/linux-iio/20231204144925.4fe9922f@jic23-huawei/T/#m222f5175273b81dbfe40b7f0daffcdc67d6cb8ff v2: https://lore.kernel.org/r/20231208-dev-iio-backend-v2-0-5450951895e1@xxxxxxxxxx v3: https://lore.kernel.org/linux-iio/20231213-dev-iio-backend-v3-0-bb9f12a5c6dc@xxxxxxxxxx/ v4: https://lore.kernel.org/r/20231220-iio-backend-v4-0-998e9148b692@xxxxxxxxxx Changes in v5: - Patch 2 * Update commit subject and message; * Add '#io-backends-cells' property. - Patch 4 * Also support '#io-backends-cells'. - Patch 6 * Improve Kconfig help message; * Only use device_links to control backends access. With this, we can remove all the mutex + sync logic as we are now guaranteed that a frontend cannot be up and running if one of the backends is gone. * Error out if we can't create the device_link (so we can guarantee the above). * Improve docs for __devm_iio_backend_get_from_fwnode_lookup(); * Add a __ prefix to devm_iio_backend_get_from_fwnode_lookup() so it's clear that API should not be used (or used with care); * Drop devm_iio_backend_get_optional(); * remove unneeded headers. - Patch 7 * Handle the optional backend in the driver. The biggest difference is that the backend @ops pointer handling to reason about the backend existence is gone. Now, we rely on device_links as that makes sure all consumers (in the link) are unbound before the provider. Hence, the frontend is guaranteed to be unbound if any of the backends is gone. That simplifies things a lot... Keeping the block diagram so we don't have to follow links to check one of the typical setups. ------------------------------------------------------- ------------------ | ----------- ------------ ------- FPGA | | ADC |------------------------| | AXI ADC |---------| DMA CORE |------| RAM | | | (Frontend/IIO) | Serial Data (eg: LVDS) | |(backend)|---------| |------| | | | |------------------------| ----------- ------------ ------- | ------------------ ------------------------------------------------------- --- Nuno Sa (7): dt-bindings: adc: ad9467: add new io-backend property dt-bindings: adc: axi-adc: update bindings for backend framework driver: core: allow modifying device_links flags iio: buffer-dmaengine: export buffer alloc and free functions iio: add the IIO backend framework iio: adc: ad9467: convert to backend framework iio: adc: adi-axi-adc: move to backend framework Olivier Moysan (1): of: property: add device link support for io-backends .../devicetree/bindings/iio/adc/adi,ad9467.yaml | 4 + .../devicetree/bindings/iio/adc/adi,axi-adc.yaml | 7 +- MAINTAINERS | 8 + drivers/base/core.c | 14 +- drivers/iio/Kconfig | 9 + drivers/iio/Makefile | 1 + drivers/iio/adc/Kconfig | 4 +- drivers/iio/adc/ad9467.c | 283 +++++++++----- drivers/iio/adc/adi-axi-adc.c | 381 +++++-------------- drivers/iio/buffer/industrialio-buffer-dmaengine.c | 8 +- drivers/iio/industrialio-backend.c | 411 +++++++++++++++++++++ drivers/of/property.c | 2 + include/linux/iio/adc/adi-axi-adc.h | 68 ---- include/linux/iio/backend.h | 73 ++++ include/linux/iio/buffer-dmaengine.h | 3 + 15 files changed, 806 insertions(+), 470 deletions(-) --- base-commit: 3f4525f924e21d4f532517b17a20ffa5df7c0db7 change-id: 20231219-iio-backend-a3dc1a6a7a58 -- Thanks! - Nuno Sá