On Wed, May 15, 2024 at 09:40:54PM +0200, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > > It is reported that _DSM evaluation fails in ucsi_acpi_dsm() on Lenovo > IdeaPad Pro 5 due to a missing address space handler for the EC address > space: > > ACPI Error: No handler for Region [ECSI] (000000007b8176ee) [EmbeddedControl] (20230628/evregion-130) > > This happens because if there is no ECDT, the EC driver only registers > the EC address space handler for operation regions defined in the EC > device scope of the ACPI namespace while the operation region being > accessed by the _DSM in question is located beyond that scope. > > To address this, modify the ACPI EC driver to install the EC address > space handler at the root of the ACPI namespace for the first EC that > can be found regardless of whether or not an ECDT is present. > > Note that this change is consistent with some examples in the ACPI > specification in which EC operation regions located outside the EC > device scope are used (for example, see Section 9.17.15 in ACPI 6.5), > so the current behavior of the EC driver is arguably questionable. ... > - status = acpi_install_address_space_handler_no_reg(ec->handle, > + status = acpi_install_address_space_handler_no_reg(scope_handle, > ACPI_ADR_SPACE_EC, > &acpi_ec_space_handler, > NULL, ec); Looking at this... > if (ACPI_FAILURE(acpi_remove_address_space_handler( > + scope_handle, > + ACPI_ADR_SPACE_EC, > + &acpi_ec_space_handler))) ...and this, I believe you can move scope_handle to the previous line and align the rest for the sake of consistency and slightly better readability. -- With Best Regards, Andy Shevchenko
