[PATCH v2 0/6] Support Spi in i2c-multi-instantiate driver

Stefan Binding
2021-12-10T15:42:11Z

Add support for SPI bus in the ic2-multi-instantiate driver as
upcoming laptops will need to multi instantiate SPI devices from
a single device node, which has multiple SpiSerialBus entries at
the ACPI table.

With the new SPI support, i2c-multi-instantiate becomes
bus-multi-instantiate and is moved to the ACPI folder.

The intention is to support the SPI bus by re-using the current
I2C multi instantiate, instead of creating a new SPI multi
instantiate, to make it possible for peripherals that can be
controlled by I2C or SPI to have the same HID at the ACPI table.

The new driver (Bus multi instantiate, bmi) checks for the
hard-coded bus type and returns -ENODEV in case of zero devices
found for that bus. In the case of automatic bus detection,
the driver will give preference to I2C.

The expectation is for a device node in the ACPI table to have
multiple I2cSerialBus only or multiple SpiSerialBus only, not
a mix of both; and for the case where there are both entries in
one device node, only the I2C ones would be probed.

This new bus multi instantiate will be used in CS35L41 HDA new
driver, being upstreamed:
https://lkml.org/lkml/2021/11/23/723

Changes since V1:
- Added Cover Letter
- Split SPI patch into move, rename, reorganize and add
SPI support
- Hard coded BUS type for better decison making at bmi_probe
- Driver moved to acpi folder
- Change to use acpi_spi_find_controller_by_adev
- New shared function bmi_get_irq for I2C and SPI

Lucas Tanure (3):
platform/x86: i2c-multi-instantiate: Move it to drivers/acpi folder
ACPI: i2c-multi-instantiate: Rename it for a generic bus driver name
ACPI: bus-multi-instantiate: Reorganize I2C functions

Stefan Binding (3):
spi: Export acpi_spi_find_controller_by_adev to be used externally
spi: Make spi_alloc_device and spi_add_device public again
ACPI: bus-multi-instantiate: Add SPI support

MAINTAINERS | 4 +-
drivers/acpi/Kconfig | 11 +
drivers/acpi/Makefile | 1 +
drivers/acpi/bus-multi-instantiate.c | 500 +++++++++++++++++++
drivers/acpi/scan.c | 19 +-
drivers/platform/x86/Kconfig | 11 -
drivers/platform/x86/Makefile | 1 -
drivers/platform/x86/i2c-multi-instantiate.c | 174 -------
drivers/spi/spi.c | 9 +-
include/linux/spi/spi.h | 22 +
10 files changed, 552 insertions(+), 200 deletions(-)
create mode 100644 drivers/acpi/bus-multi-instantiate.c
delete mode 100644 drivers/platform/x86/i2c-multi-instantiate.c

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2.25.1