Re: [PATCH v5 2/8] acpi: fix enumeration (visited) flags for bus rescans

From: Mika Westerberg
Date: Thu Jul 07 2016 - 05:28:34 EST


On Fri, Jul 01, 2016 at 11:19:06PM +0300, Octavian Purdila wrote:
> If the ACPI tables changes as a result of a dinamically loaded table and
> a bus rescan is required the enumeration/visited flag are not
> consistent.
>
> I2C/SPI are not directly enumerated in acpi_bus_attach(), however the
> visited flag is set. This makes it impossible to check if an ACPI device
> has already been enumerated by the I2C and SPI subsystems. To fix this
> issue we only set the visited flags if the device is not I2C or SPI.
>
> With this change we also need to remove setting visited to false from
> acpi_bus_attach(), otherwise if we rescan already enumerated I2C/SPI
> devices we try to re-enumerate them.
>
> Note that I2C/SPI devices can be enumerated either via a scan handler
> (when using PRP0001) or via regular device_attach(). In either case
> the flow goes through acpi_default_enumeration() which makes it the
> ideal place to mark the ACPI device as enumerated.
>
> Signed-off-by: Octavian Purdila <octavian.purdila@xxxxxxxxx>

Reviewed-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>