RE: [PATCH 5.4 064/134] ACPI: GED: add support for _Exx / _Lxx handler methods

[nobuhiro1.iwamatsu]

Hi,

> -----Original Message-----
> From: stable-owner@xxxxxxxxxxxxxxx [mailto:stable-owner@xxxxxxxxxxxxxxx] On Behalf Of Greg Kroah-Hartman
> Sent: Wednesday, June 17, 2020 12:34 AM
> To: linux-kernel@xxxxxxxxxxxxxxx
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>; stable@xxxxxxxxxxxxxxx; Ard Biesheuvel <ardb@xxxxxxxxxx>; Rafael
> J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> Subject: [PATCH 5.4 064/134] ACPI: GED: add support for _Exx / _Lxx handler methods
> 
> From: Ard Biesheuvel <ardb@xxxxxxxxxx>
> 
> commit ea6f3af4c5e63f6981c0b0ab8ebec438e2d5ef40 upstream.
> 
> Per the ACPI spec, interrupts in the range [0, 255] may be handled
> in AML using individual methods whose naming is based on the format
> _Exx or _Lxx, where xx is the hex representation of the interrupt
> index.
> 
> Add support for this missing feature to our ACPI GED driver.
> 
> Cc: v4.9+ <stable@xxxxxxxxxxxxxxx> # v4.9+
> Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> 

This patch also requires the following patch.
Please apply to this kernel version, 4.9, 4.14, 4.19, 5.6 and 5.7. 

From e5c399b0bd6490c12c0af2a9eaa9d7cd805d52c9 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@xxxxxxxxxx>
Date: Wed, 27 May 2020 13:37:00 +0200

    ACPI: GED: use correct trigger type field in _Exx / _Lxx handling

    Commit ea6f3af4c5e63f69 ("ACPI: GED: add support for _Exx / _Lxx handler
    methods") added a reference to the 'triggering' field of either the
    normal or the extended ACPI IRQ resource struct, but inadvertently used
    the wrong pointer in the latter case. Note that both pointers refer to the
    same union, and the 'triggering' field appears at the same offset in both
    struct types, so it currently happens to work by accident. But let's fix
    it nonetheless

    Fixes: ea6f3af4c5e63f69 ("ACPI: GED: add support for _Exx / _Lxx handler methods")
    Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
    Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Best regards,
  Nobuhiro

> ---
>  drivers/acpi/evged.c |   22 +++++++++++++++++++---
>  1 file changed, 19 insertions(+), 3 deletions(-)
> 
> --- a/drivers/acpi/evged.c
> +++ b/drivers/acpi/evged.c
> @@ -79,6 +79,8 @@ static acpi_status acpi_ged_request_inte
>  	struct resource r;
>  	struct acpi_resource_irq *p = &ares->data.irq;
>  	struct acpi_resource_extended_irq *pext = &ares->data.extended_irq;
> +	char ev_name[5];
> +	u8 trigger;
> 
>  	if (ares->type == ACPI_RESOURCE_TYPE_END_TAG)
>  		return AE_OK;
> @@ -87,14 +89,28 @@ static acpi_status acpi_ged_request_inte
>  		dev_err(dev, "unable to parse IRQ resource\n");
>  		return AE_ERROR;
>  	}
> -	if (ares->type == ACPI_RESOURCE_TYPE_IRQ)
> +	if (ares->type == ACPI_RESOURCE_TYPE_IRQ) {
>  		gsi = p->interrupts[0];
> -	else
> +		trigger = p->triggering;
> +	} else {
>  		gsi = pext->interrupts[0];
> +		trigger = p->triggering;
> +	}
> 
>  	irq = r.start;
> 
> -	if (ACPI_FAILURE(acpi_get_handle(handle, "_EVT", &evt_handle))) {
> +	switch (gsi) {
> +	case 0 ... 255:
> +		sprintf(ev_name, "_%c%02hhX",
> +			trigger == ACPI_EDGE_SENSITIVE ? 'E' : 'L', gsi);
> +
> +		if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
> +			break;
> +		/* fall through */
> +	default:
> +		if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
> +			break;
> +
>  		dev_err(dev, "cannot locate _EVT method\n");
>  		return AE_ERROR;
>  	}
>