Hello everyone, This is version three of my series which adds support for the TI FPC202 dual-port controller. This is an unusual kind of device which is used as a low-speed signal aggregator for various types of SFP-like hardware ports. The FPC202 exposes an I2C, or SPI (not supported in this series) control interface, which can be used to access two downstream I2C busses, along with a set of low-speed GPIO signals for each port. It also has I2C address translation (ATR) features, which allow multiple I2C devices with the same address (e.g. SFP EEPROMs at address 0x50) to be accessed from the upstream control interface on different addresses. I've chosen to add this driver to the misc subsystem, as it doesn't strictly belong in either the i2c or gpio sybsystem, and as far as I know it is the first device of its kind to be added to the kernel. Along with the FPC202 driver itself, this series also adds support for dynamic address translation to the i2c-atr module. This allows I2C address translators to update their translation table on-the-fly when they receive transactions to unmapped clients. This feature is needed by the FPC202 driver to access up to three logical I2C devices per-port, given that the FPC202 address translation table only has two address slots. Best Regards, Romain Signed-off-by: Romain Gantois <romain.gantois@xxxxxxxxxxx> --- Changes in v3: - Described the "reg" property of downstream ports in the FPC202 bindings - Link to v2: https://lore.kernel.org/r/20241118-fpc202-v2-0-744e4f192a2d@xxxxxxxxxxx Changes in v2: - Renamed port nodes to match i2c adapter bindings. - Declared atr ops struct as static const. - Free downstream ports during FPC202 removal. - Link to v1: https://lore.kernel.org/r/20241108-fpc202-v1-0-fe42c698bc92@xxxxxxxxxxx --- Romain Gantois (9): dt-bindings: misc: Describe TI FPC202 dual port controller media: i2c: ds90ub960: Replace aliased clients list with bitmap media: i2c: ds90ub960: Protect alias_use_mask with a mutex i2c: use client addresses directly in ATR interface i2c: move ATR alias pool to a separate struct i2c: rename field 'alias_list' of struct i2c_atr_chan to 'alias_pairs' i2c: support per-channel ATR alias pools i2c: Support dynamic address translation misc: add FPC202 dual port controller driver .../devicetree/bindings/misc/ti,fpc202.yaml | 96 +++++ MAINTAINERS | 7 + drivers/i2c/i2c-atr.c | 480 ++++++++++++++------- drivers/media/i2c/ds90ub913.c | 9 +- drivers/media/i2c/ds90ub953.c | 9 +- drivers/media/i2c/ds90ub960.c | 65 +-- drivers/misc/Kconfig | 11 + drivers/misc/Makefile | 1 + drivers/misc/ti_fpc202.c | 440 +++++++++++++++++++ include/linux/i2c-atr.h | 67 ++- 10 files changed, 989 insertions(+), 196 deletions(-) --- base-commit: adc218676eef25575469234709c2d87185ca223a change-id: 20241017-fpc202-6f0b739c2078 Best regards, -- Romain Gantois <romain.gantois@xxxxxxxxxxx>
