Re: [PATCH 5/6] PCI: acpiphp: look _RMV method a bit deeper in the hierarhcy

From: Andy Shevchenko
Date: Tue Jun 25 2013 - 14:16:03 EST


On Tue, Jun 25, 2013 at 7:22 PM, Mika Westerberg
<mika.westerberg@xxxxxxxxxxxxxxx> wrote:

> The acpiphp driver finds out whether the device is hotpluggable by checking
> whether it has _RMV method behind it (and if it returns 1). However, at
> least Acer Aspire S5 with Thunderbolt host router has this method placed
> behind device called EPUP (endpoint upstream port?) and not directly behind
> the root port as can be seen from the ASL code below:

[]


> +static acpi_status pcihp_evaluate_rmv(acpi_handle handle, u32 lvl,
> + void *context, void **return_not_used)
> +{
> + unsigned long long *removable = context;
> + unsigned long long value;
> + acpi_status status;
> +
> + status = acpi_evaluate_integer(handle, "_RMV", NULL, &value);
> + if (ACPI_SUCCESS(status) && value) {

So, there is a chance the caller gets back uninitialized *context.
Let's assume that is by design.

> + *removable = value;
> + return AE_CTRL_TERMINATE;
> + }
> + return AE_OK;
> +}


> +static bool pcihp_is_removable(acpi_handle handle, size_t depth)
> +{
> + unsigned long long removable = 0;
> + acpi_status status;
> +
> + status = pcihp_evaluate_rmv(handle, 0, &removable, NULL);
> + if ((status == AE_CTRL_TERMINATE) && removable)

Here you already have removable not equal zero.

Internal braces could be removed, but it's up top you.

> + return true;
> +
> + acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, depth, pcihp_evaluate_rmv,
> + NULL, &removable, NULL);
> + return !!removable;
> +}


--
With Best Regards,
Andy Shevchenko
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