On Tuesday, April 08, 2014 12:06:59 AM Zhang Rui wrote: > For some devices with scan handler attached, their children devices > are enumerated by the scan handler, indirectly.
This isn't the case really. They are enumerated by bus controller drivers for the buses they are on. > In this case, we do not want to enumerate the children devices in > acpi scan code explicitly. > > Thus a new flag .handle_children is introduced in this patch. > > For scan handlers with this flag set, we will do default enumeration neither > for the attached devices nor for the children of the attached devices. I'm not sure if that is the right approach. I would prefer that to be handled in a more fine-graind manner, like a flag per device ID or something similar? > Signed-off-by: Zhang Rui <[email protected]> > --- > drivers/acpi/acpi_lpss.c | 2 ++ > drivers/acpi/scan.c | 28 ++++++++++++++++++++++++++-- > include/acpi/acpi_bus.h | 4 +++- > 3 files changed, 31 insertions(+), 3 deletions(-) > > diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c > index 965428f..da0a3d4 100644 > --- a/drivers/acpi/acpi_lpss.c > +++ b/drivers/acpi/acpi_lpss.c > @@ -521,6 +521,7 @@ static struct acpi_scan_handler lpss_handler = { > .attach = acpi_lpss_create_device, > .bind = acpi_lpss_bind, > .unbind = acpi_lpss_unbind, > + .handle_children = true, > }; > > #endif /* CONFIG_X86_INTEL_LPSS */ > @@ -534,6 +535,7 @@ static int acpi_lpss_dummy_attach(struct acpi_device > *adev, > static struct acpi_scan_handler lpss_dummy_handler = { > .ids = acpi_lpss_device_ids, > .attach = acpi_lpss_dummy_attach, > + .handle_children = true, > }; > > void __init acpi_lpss_init(void) > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > index 44c4668..4ea867e 100644 > --- a/drivers/acpi/scan.c > +++ b/drivers/acpi/scan.c > @@ -2073,6 +2073,31 @@ static acpi_status acpi_bus_check_add(acpi_handle > handle, u32 lvl_not_used, > return AE_OK; > } > > +static void acpi_do_default_enumeration(struct acpi_device *device) > +{ > + /* > + * Do not do enumeration for device object that > + * its parent doesn't want to > + */ > + if (device->parent && device->parent->flags.no_child_enumeration) { > + device->flags.no_child_enumeration = 1; > + return; > + } > + > + /* Do not do enumeration for device object with scan handler attached */ > + if (device->handler) { > + if (device->handler->handle_children) > + device->flags.no_child_enumeration = 1; > + return; > + } > + > + /* Do not do enumeration for device object w/o platform_id */ > + if (!device->pnp.type.platform_id) > + return; > + > + acpi_create_platform_device(device, NULL); > +} > + > static int acpi_scan_attach_handler(struct acpi_device *device) > { > struct acpi_hardware_id *hwid; > @@ -2095,8 +2120,7 @@ static int acpi_scan_attach_handler(struct acpi_device > *device) > } > } > > - if (device->pnp.type.platform_id && !device->handler) > - acpi_create_platform_device(device, NULL); > + acpi_do_default_enumeration(device); > > return ret; > } > diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h > index ec92ad3..4724fe5 100644 > --- a/include/acpi/acpi_bus.h > +++ b/include/acpi/acpi_bus.h > @@ -137,6 +137,7 @@ struct acpi_scan_handler { > void (*bind)(struct device *phys_dev); > void (*unbind)(struct device *phys_dev); > struct acpi_hotplug_profile hotplug; > + bool handle_children; > }; > > /* > @@ -207,7 +208,8 @@ struct acpi_device_flags { > u32 no_hotplug:1; > u32 hotplug_notify:1; > u32 is_dock_station:1; > - u32 reserved:22; > + u32 no_child_enumeration:1; > + u32 reserved:21; > }; > > /* File System */ > -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
