From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756357AbbLGWTA (ORCPT ); Mon, 7 Dec 2015 17:19:00 -0500 Received: from v094114.home.net.pl ([79.96.170.134]:55219 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1756007AbbLGWS7 (ORCPT ); Mon, 7 Dec 2015 17:18:59 -0500 From: "Rafael J. Wysocki" To: Ken Xue Cc: lenb@kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, SPG_Linux_Kernel@amd.com, mika.westerberg@linux.intel.com, Andy Shevchenko , Ivan.Zheng@amd.com, Alex.Chuang@amd.com Subject: Re: [PATCH 1/1] ACPI: Support D3 COLD device for old BIOS Date: Mon, 07 Dec 2015 23:48:56 +0100 Message-ID: <3822904.Z6rtg8lMJ5@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/4.1.0-rc5+; KDE/4.11.5; x86_64; ; ) In-Reply-To: <1449463473.2175.13.camel@kxue-X58A-UD3R> References: <1449463473.2175.13.camel@kxue-X58A-UD3R> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Monday, December 07, 2015 12:44:33 PM Ken Xue wrote: > D3cold is only regarded as valid if the "_PR3" object is present > for the given device after the commit <20dacb71ad28> > (ACPI/PM: Reworkdevice power management to follow ACPI 6). > > But some old BIOS only defined "_PS3" for the D3COLD device. > And old kernel also believes the device has "_PS3" is a > D3COLD device. > > So, add some logics for supporting D3 COLD device for old BIOS > which is compatible with earlier ACPI spec. > > Signed-off-by: Ken Xue > Reported-and-tested-by: Gang Long Well, what really is the problem? acpi_device_set_power() has a special case specifically for D3cold and falls back to D3hot if D3cold has been requested but is not "valid". > --- > drivers/acpi/scan.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > index 01136b8..85c16bb 100644 > --- a/drivers/acpi/scan.c > +++ b/drivers/acpi/scan.c > @@ -979,7 +979,9 @@ static void acpi_bus_get_power_flags(struct acpi_device *device) > acpi_bus_init_power_state(device, i); > > INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources); > - if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources)) > + if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources) || > + ((acpi_gbl_FADT.header.revision < 6) && > + device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)) > device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1; > > /* Set defaults for D0 and D3hot states (always valid) */ > -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center.