Hi Stefan, On 12/10/21 16:40, Stefan Binding wrote: > 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 Unfortunately you never really answered my questions about v1 of this series: https://lore.kernel.org/platform-driver-x86/a1f546c2-5c63-573a-c032-603c792f3f7c@xxxxxxxxxx/ So looking at the linked CS35L41 HDA series there is a single ACPI device node with a HID of CLSA0100 which describes two CS35L41 amplifiers connected over I2C ? I assume you are doing this work because there are also designs where there is a similar CLSA0100 ACPI device which also describes two CS35L41 amplifiers but then connected over SPI ? It would really help if you can: 1. Answer my questions from v1 2. Provide a concrete example of a device where these changes will be necessary to make things work, preferably with a link to an actual ACPI DSDT of that device. Until you can better clarify why this is necessary, this series gets a nack from me. The i2c-mult-instantiate code is a hack to deal with some rather sub-optimal choices made in DSDTs used on devices shipped with Windows and unless absolutely necessary I would rather not see this get expanded to SPI. Regards, Hans
