From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: [PATCH] ACPI / PM: Add check preventing transitioning to non-D0 state from D3. Date: Fri, 16 Nov 2012 02:49:54 +0100 Message-ID: <2072306.j28QTtV7ui@vostro.rjw.lan> References: Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7Bit Return-path: Received: from ogre.sisk.pl ([193.178.161.156]:47545 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750784Ab2KPBpb (ORCPT ); Thu, 15 Nov 2012 20:45:31 -0500 In-Reply-To: Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Lv Zheng Cc: Len Brown , Rafael J Wysocki , linux-acpi@vger.kernel.org, Len Brown On Thursday, November 15, 2012 12:25:01 PM Lv Zheng wrote: > No power transitioning from D3 state to a non-D0 state is allowed. > This patch also cleans up device power updating code in the > acpi_device_set_power() as it should already been updated in the > acpi_power_transition(). > > Signed-off-by: Lv Zheng > --- > drivers/acpi/bus.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c > index 07a20ee..12c1b51 100644 > --- a/drivers/acpi/bus.c > +++ b/drivers/acpi/bus.c > @@ -293,6 +293,12 @@ int acpi_device_set_power(struct acpi_device *device, int state) > " state than parent\n"); > return -ENODEV; > } > + if (device->parent->power.state >= ACPI_STATE_D3_HOT && Why parent? The device's own power state shouldn't be D3, right? > + state != ACPI_STATE_D0) { > + printk(KERN_WARNING PREFIX > + "Cannot transition to non-D0 state from D3\n"); > + return -ENODEV; > + } I fixed up the check and moved it into the (state < device->power.state) block, because otherwise it would prevent transitions from D3_HOT to D3_COLD from being carried out, but they are allowed. > /* For D3cold we should execute _PS3, not _PS4. */ > if (state == ACPI_STATE_D3_COLD) > @@ -341,7 +347,6 @@ int acpi_device_set_power(struct acpi_device *device, int state) > "Device [%s] failed to transition to %s\n", > device->pnp.bus_id, state_string(state)); > else { > - device->power.state = state; > ACPI_DEBUG_PRINT((ACPI_DB_INFO, > "Device [%s] transitioned to %s\n", > device->pnp.bus_id, state_string(state))); > Please check the linux-next branch of linux-pm.git and see if that's what you wanted. :-) Thanks, Rafael -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center.