Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758095Ab2BMUoP (ORCPT ); Mon, 13 Feb 2012 15:44:15 -0500 Received: from ogre.sisk.pl ([217.79.144.158]:50416 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754696Ab2BMUoM (ORCPT ); Mon, 13 Feb 2012 15:44:12 -0500 From: "Rafael J. Wysocki" To: Lin Ming Subject: Re: [RFC PATCH 2/6] ACPI: Reference devices in ACPI Power Resource Date: Mon, 13 Feb 2012 21:48:04 +0100 User-Agent: KMail/1.13.6 (Linux/3.3.0-rc3+; KDE/4.6.0; x86_64; ; ) Cc: Zhang Rui , Jeff Garzik , Alan Stern , Tejun Heo , Len Brown , linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org, linux-scsi@vger.kernel.org, linux-pm@vger.kernel.org References: <1329124271-29464-1-git-send-email-ming.m.lin@intel.com> <1329124271-29464-3-git-send-email-ming.m.lin@intel.com> In-Reply-To: <1329124271-29464-3-git-send-email-ming.m.lin@intel.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-2" Content-Transfer-Encoding: 7bit Message-Id: <201202132148.04961.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6558 Lines: 204 On Monday, February 13, 2012, Lin Ming wrote: > From: Zhang Rui > > ACPI Power Resource can power on/off a couple of devices. > Introduce interfaces to register/unregister a device to/from > an ACPI Power Resource. > > Signed-off-by: Zhang Rui > --- > drivers/acpi/power.c | 128 +++++++++++++++++++++++++++++++++++++++++++++++ > include/acpi/acpi_bus.h | 2 + > 2 files changed, 130 insertions(+), 0 deletions(-) > > diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c > index 0d681fb..a7e2305 100644 > --- a/drivers/acpi/power.c > +++ b/drivers/acpi/power.c > @@ -84,10 +84,25 @@ struct acpi_power_resource { > u32 order; > unsigned int ref_count; > struct mutex resource_lock; > + struct list_head devices; /* list for devices powered by this PR */ > }; > > static struct list_head acpi_power_resource_list; > > +/* > + * When a power resource is turned on, all the devices are put to an uninitialized > + * state although their ACPI states are still D0. > + * To handle this, we need to keep a list of all devices powered by the power resource, > + * and resume all of them. > + * Currently, we only support this case: > + * 1) multiple devices share the same power resoruce, > + * 2) One device uses One Power Resource ONLY. This is incorrect. We actually support all combinations. However, we don't generally support checking what devices depend on the given power resource. > + */ > +struct acpi_powered_device { > + struct list_head node; > + struct device *dev; > +}; > + > /* -------------------------------------------------------------------------- > Power Resource Management > -------------------------------------------------------------------------- */ > @@ -455,6 +470,118 @@ int acpi_disable_wakeup_device_power(struct acpi_device *dev) > Device Power Management > -------------------------------------------------------------------------- */ > > +int acpi_power_resource_register_device(struct device *dev, acpi_handle handle) > +{ > + struct acpi_power_resource *resource; > + struct acpi_device *acpi_dev, *res_dev; > + acpi_handle res_handle = NULL; > + struct acpi_powered_device *apd; > + int i; > + int ret; > + > + if (!handle || !dev) > + return -EINVAL; > + > + ret = acpi_bus_get_device(handle, &acpi_dev); > + if (ret) > + goto no_power_resource; > + > + if (!acpi_dev->power.flags.power_resources) > + goto no_power_resource; > + > + for (i = 0; i <= ACPI_STATE_D3; i++) { > + struct acpi_device_power_state *ps = &acpi_dev->power.states[i]; > + > + if (!ps->flags.valid) > + continue; > + > + if (ps->resources.count > 1) > + return 0; > + > + if (!res_handle) > + res_handle = ps->resources.handles[0]; > + else if (res_handle != ps->resources.handles[0]) > + return 0; > + } I'm not sure what the above checks are needed for. It seems that this function will only be called from acpi_bus_add_power_resource() (which needs to be modified for this purpose, BTW), so it doesn't need to check all those things (those checks have been made already). > + > + ret = acpi_bus_get_device(res_handle, &res_dev); > + if (ret) > + goto no_power_resource; > + > + resource = res_dev->driver_data; > + if (!resource) > + goto no_power_resource; > + > + apd = kzalloc(sizeof(struct acpi_powered_device), GFP_KERNEL); > + if (!apd) > + return -ENOMEM; > + > + apd->dev = dev; > + mutex_lock(&resource->resource_lock); > + list_add_tail(&apd->node, &resource->devices); > + mutex_unlock(&resource->resource_lock); > + printk(KERN_INFO PREFIX "Device %s uses Power Resource %s\n", dev->kobj.name, acpi_device_name(res_dev)); > + > + return 0; > + > +no_power_resource: > + printk(KERN_WARNING PREFIX "Invalid Power Resource to register!"); > + return -ENODEV; > +} > + > +void acpi_power_resource_unregister_device(struct device *dev, acpi_handle handle) > +{ Who is supposed to call this one? > + struct acpi_power_resource *resource; > + struct acpi_device *acpi_dev, *res_dev; > + acpi_handle res_handle = NULL; > + struct acpi_powered_device *apd, *tmp; > + int i; > + int ret; > + > + if (!handle || !dev) > + return; > + > + ret = acpi_bus_get_device(handle, &acpi_dev); > + if (ret) > + return; > + > + if (!acpi_dev->power.flags.power_resources) > + return; > + > + for (i = 0; i <= ACPI_STATE_D3; i++) { > + struct acpi_device_power_state *ps = &acpi_dev->power.states[i]; > + > + if (!ps->flags.valid) > + continue; > + > + if (ps->resources.count > 1) > + return; > + > + res_handle = ps->resources.handles[0]; > + break; > + } > + > + if (!res_handle) > + return; > + > + ret = acpi_bus_get_device(res_handle, &res_dev); > + if (ret) > + return; > + > + resource = res_dev->driver_data; > + if (!resource) > + return; > + > + mutex_lock(&resource->resource_lock); > + list_for_each_entry_safe(apd, tmp, &resource->devices, node) { > + if (apd->dev == dev) { > + list_del(&apd->node); > + kfree(apd); > + } > + } > + mutex_unlock(&resource->resource_lock); > +} > + > int acpi_power_get_inferred_state(struct acpi_device *device, int *state) > { > int result = 0; > @@ -550,6 +677,7 @@ static int acpi_power_add(struct acpi_device *device) > > resource->device = device; > mutex_init(&resource->resource_lock); > + INIT_LIST_HEAD(&resource->devices); > strcpy(resource->name, device->pnp.bus_id); > strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME); > strcpy(acpi_device_class(device), ACPI_POWER_CLASS); > diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h > index 6cd5b64..32fb899 100644 > --- a/include/acpi/acpi_bus.h > +++ b/include/acpi/acpi_bus.h > @@ -322,6 +322,8 @@ int acpi_bus_get_status(struct acpi_device *device); > 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); > +int acpi_power_resource_register_device(struct device *dev, acpi_handle handle); > +void acpi_power_resource_unregister_device(struct device *dev, acpi_handle handle); > bool acpi_bus_can_wakeup(acpi_handle handle); > #ifdef CONFIG_ACPI_PROC_EVENT > int acpi_bus_generate_proc_event(struct acpi_device *device, u8 type, int data); Thanks, Rafael -- 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/