On 07/08/2018 09:05, Hans de Goede wrote:
On systems with ACPI instantiated i2c-clients, normally there is 1 fw_node per i2c-device and that fw-node contains 1 I2cSerialBus resource for that 1 i2c-device. But in some rare cases the manufacturer has decided to describe multiple i2c-devices in a single ACPI fwnode with multiple I2cSerialBus resources. An earlier attempt to fix this in the i2c-core resulted in a lot of extra code to support this corner-case. This commit introduces a new i2c-multi-instantiate driver which fixes this in a different way. This new driver can be built as a module which will only loaded on affected systems. This driver will instantiate a new i2c-client per I2cSerialBus resource, using the driver_data from the acpi_device_id it is binding to to tell it which chip-type (and optional irq-resource) to use when instantiating. Note this driver depends on a platform device being instantiated for the ACPI fwnode, see the i2c_multi_instantiate_ids list of ACPI device-ids in drivers/acpi/scan.c: acpi_device_enumeration_by_parent(). Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> --- MAINTAINERS | 6 + drivers/platform/x86/Kconfig | 11 ++ drivers/platform/x86/Makefile | 1 + drivers/platform/x86/i2c-multi-instantiate.c | 131 +++++++++++++++++++ 4 files changed, 149 insertions(+) create mode 100644 drivers/platform/x86/i2c-multi-instantiate.c diff --git a/MAINTAINERS b/MAINTAINERS index 9b377508f24f..09e16d76cab7 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -6657,6 +6657,12 @@ F: drivers/i2c/i2c-mux.c F: drivers/i2c/muxes/ F: include/linux/i2c-mux.h +I2C MULTI INSTANTIATE DRIVER +M: Hans de Goede <hdegoede@xxxxxxxxxx> +L: linux-i2c@xxxxxxxxxxxxxxx +S: Maintained +F: drivers/drivers/platform/x86/i2c-multi-instantiate.c
This path looks incorrect
+ I2C MV64XXX MARVELL AND ALLWINNER DRIVER M: Gregory CLEMENT <gregory.clement@xxxxxxxxxxx> L: linux-i2c@xxxxxxxxxxxxxxx diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig index 85a93453237c..8256629f58f7 100644 --- a/drivers/platform/x86/Kconfig +++ b/drivers/platform/x86/Kconfig @@ -1219,6 +1219,17 @@ config INTEL_CHTDC_TI_PWRBTN To compile this driver as a module, choose M here: the module will be called intel_chtdc_ti_pwrbtn. +config I2C_MULTI_INSTANTIATE + tristate "I2C multi instantiate pseudo device driver" + depends on I2C && ACPI + help + Some ACPI bases systems list multiple i2c-devices in a single ACPI
I guess that this should be "Some ACPI-based systems"
+ firmware-node. This driver will instantiate separate i2c-clients + for each device in the firmware-node. + + To compile this driver as a module, choose M here: the module + will be called i2c-multi-instantiate. +
Thanks, John
