Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756624Ab0KXXRl (ORCPT ); Wed, 24 Nov 2010 18:17:41 -0500 Received: from ogre.sisk.pl ([217.79.144.158]:52764 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932192Ab0KXXRU (ORCPT ); Wed, 24 Nov 2010 18:17:20 -0500 From: "Rafael J. Wysocki" To: Len Brown Subject: [PATCH 8/13] ACPI / PM: Add function for updating device power state consistently Date: Thu, 25 Nov 2010 00:09:15 +0100 User-Agent: KMail/1.13.5 (Linux/2.6.37-rc3+; KDE/4.4.4; x86_64; ; ) Cc: ACPI Devel Maling List , LKML , "Linux-pm mailing list" , Matthew Garrett , Maciej Rutecki References: <201011250001.11297.rjw@sisk.pl> In-Reply-To: <201011250001.11297.rjw@sisk.pl> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <201011250009.15501.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5246 Lines: 161 From: Rafael J. Wysocki Add function acpi_bus_update_power() for reading the actual power state of an ACPI device and updating its device->power.state field in such a way that its power resources' reference counters will remain consistent with that field. For this purpose introduce __acpi_bus_set_power() setting the power state of an ACPI device without updating its device->power.state field and make acpi_bus_set_power() and acpi_bus_update_power() use it (acpi_bus_set_power() retains the current behavior for now). Signed-off-by: Rafael J. Wysocki --- drivers/acpi/bus.c | 90 ++++++++++++++++++++++++++++++++---------------- include/acpi/acpi_bus.h | 1 2 files changed, 62 insertions(+), 29 deletions(-) Index: linux-2.6/drivers/acpi/bus.c =================================================================== --- linux-2.6.orig/drivers/acpi/bus.c +++ linux-2.6/drivers/acpi/bus.c @@ -255,44 +255,17 @@ int acpi_bus_get_power(acpi_handle handl EXPORT_SYMBOL(acpi_bus_get_power); -int acpi_bus_set_power(acpi_handle handle, int state) +static int __acpi_bus_set_power(struct acpi_device *device, int state) { int result = 0; acpi_status status = AE_OK; - struct acpi_device *device = NULL; char object_name[5] = { '_', 'P', 'S', '0' + state, '\0' }; - - result = acpi_bus_get_device(handle, &device); - if (result) - return result; - - if ((state < ACPI_STATE_D0) || (state > ACPI_STATE_D3)) + if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3)) return -EINVAL; /* Make sure this is a valid target state */ - if (!device->flags.power_manageable) { - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device `[%s]' is not power manageable\n", - kobject_name(&device->dev.kobj))); - return -ENODEV; - } - /* - * Get device's current power state - */ - if (!acpi_power_nocheck) { - /* - * Maybe the incorrect power state is returned on the bogus - * bios, which is different with the real power state. - * For example: the bios returns D0 state and the real power - * state is D3. OS expects to set the device to D0 state. In - * such case if OS uses the power state returned by the BIOS, - * the device can't be transisted to the correct power state. - * So if the acpi_power_nocheck is set, it is unnecessary to - * get the power state by calling acpi_bus_get_power. - */ - acpi_bus_get_power(device->handle, &device->power.state); - } if ((state == device->power.state) && !device->flags.force_power_state) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n", state)); @@ -362,6 +335,42 @@ int acpi_bus_set_power(acpi_handle handl return result; } + +int acpi_bus_set_power(acpi_handle handle, int state) +{ + struct acpi_device *device; + int result; + + result = acpi_bus_get_device(handle, &device); + if (result) + return result; + + if (!device->flags.power_manageable) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "Device [%s] is not power manageable\n", + dev_name(&device->dev))); + return -ENODEV; + } + + /* + * Get device's current power state + */ + if (!acpi_power_nocheck) { + /* + * Maybe the incorrect power state is returned on the bogus + * bios, which is different with the real power state. + * For example: the bios returns D0 state and the real power + * state is D3. OS expects to set the device to D0 state. In + * such case if OS uses the power state returned by the BIOS, + * the device can't be transisted to the correct power state. + * So if the acpi_power_nocheck is set, it is unnecessary to + * get the power state by calling acpi_bus_get_power. + */ + __acpi_bus_get_power(device, &device->power.state); + } + + return __acpi_bus_set_power(device, state); +} EXPORT_SYMBOL(acpi_bus_set_power); @@ -389,6 +398,29 @@ int acpi_bus_init_power(struct acpi_devi } +int acpi_bus_update_power(acpi_handle handle, int *state_p) +{ + struct acpi_device *device; + int state; + int result; + + result = acpi_bus_get_device(handle, &device); + if (result) + return result; + + result = __acpi_bus_get_power(device, &state); + if (result) + return result; + + result = __acpi_bus_set_power(device, state); + if (!result && state_p) + *state_p = state; + + return result; +} +EXPORT_SYMBOL_GPL(acpi_bus_update_power); + + bool acpi_bus_power_manageable(acpi_handle handle) { struct acpi_device *device; Index: linux-2.6/include/acpi/acpi_bus.h =================================================================== --- linux-2.6.orig/include/acpi/acpi_bus.h +++ linux-2.6/include/acpi/acpi_bus.h @@ -330,6 +330,7 @@ acpi_status acpi_bus_get_status_handle(a int acpi_bus_get_status(struct acpi_device *device); int acpi_bus_get_power(acpi_handle handle, int *state); int acpi_bus_set_power(acpi_handle handle, int state); +int acpi_bus_update_power(acpi_handle handle, int *state_p); bool acpi_bus_power_manageable(acpi_handle handle); bool acpi_bus_can_wakeup(acpi_handle handle); #ifdef CONFIG_ACPI_PROC_EVENT -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/