From b41a60eca833d76593d4dac8a59f5c38714194ee Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Wed, 30 May 2007 15:39:33 -0400 Subject: USB: add power/persist device attribute This patch (as920) adds an extra level of protection to the USB-Persist facility. Now it will apply by default only to hubs; for all other devices the user must enable it explicitly by setting the power/persist device attribute. The disconnect_all_children() routine in hub.c has been removed and its code placed inline. This is the way it was originally as part of hub_pre_reset(); the revised usage in hub_reset_resume() is sufficiently different that the code can no longer be shared. Likewise, mark_children_for_reset() is now inline as part of hub_reset_resume(). The end result looks much cleaner than before. The sysfs interface is updated to add the new attribute file, and there are corresponding documentation updates. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hub.c | 78 +++++++++++++++++++------------------------------- 1 file changed, 29 insertions(+), 49 deletions(-) (limited to 'drivers/usb/core/hub.c') diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index c4cdb69a6e9..50e79010401 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -596,27 +596,18 @@ static void hub_port_logical_disconnect(struct usb_hub *hub, int port1) kick_khubd(hub); } -static void disconnect_all_children(struct usb_hub *hub, int logical) -{ - struct usb_device *hdev = hub->hdev; - int port1; - - for (port1 = 1; port1 <= hdev->maxchild; ++port1) { - if (hdev->children[port1-1]) { - if (logical) - hub_port_logical_disconnect(hub, port1); - else - usb_disconnect(&hdev->children[port1-1]); - } - } -} - /* caller has locked the hub device */ static int hub_pre_reset(struct usb_interface *intf) { struct usb_hub *hub = usb_get_intfdata(intf); + struct usb_device *hdev = hub->hdev; + int i; - disconnect_all_children(hub, 0); + /* Disconnect all the children */ + for (i = 0; i < hdev->maxchild; ++i) { + if (hdev->children[i]) + usb_disconnect(&hdev->children[i]); + } hub_quiesce(hub); return 0; } @@ -1872,50 +1863,39 @@ static int hub_resume(struct usb_interface *intf) return 0; } -#ifdef CONFIG_USB_PERSIST - -/* For "persistent-device" resets we must mark the child devices for reset - * and turn off a possible connect-change status (so khubd won't disconnect - * them later). - */ -static void mark_children_for_reset_resume(struct usb_hub *hub) +static int hub_reset_resume(struct usb_interface *intf) { + struct usb_hub *hub = usb_get_intfdata(intf); struct usb_device *hdev = hub->hdev; int port1; + hub_power_on(hub); + for (port1 = 1; port1 <= hdev->maxchild; ++port1) { struct usb_device *child = hdev->children[port1-1]; if (child) { - child->reset_resume = 1; - clear_port_feature(hdev, port1, - USB_PORT_FEAT_C_CONNECTION); + + /* For "USB_PERSIST"-enabled children we must + * mark the child device for reset-resume and + * turn off the connect-change status to prevent + * khubd from disconnecting it later. + */ + if (USB_PERSIST && child->persist_enabled) { + child->reset_resume = 1; + clear_port_feature(hdev, port1, + USB_PORT_FEAT_C_CONNECTION); + + /* Otherwise we must disconnect the child, + * but as we may not lock the child device here + * we have to do a "logical" disconnect. + */ + } else { + hub_port_logical_disconnect(hub, port1); + } } } -} - -#else - -static inline void mark_children_for_reset_resume(struct usb_hub *hub) -{ } - -#endif /* CONFIG_USB_PERSIST */ - -static int hub_reset_resume(struct usb_interface *intf) -{ - struct usb_hub *hub = usb_get_intfdata(intf); - hub_power_on(hub); - if (USB_PERSIST) - mark_children_for_reset_resume(hub); - else { - /* Reset-resume doesn't call pre_reset, so we have to - * disconnect the children here. But we may not lock - * the child devices, so we have to do a "logical" - * disconnect. - */ - disconnect_all_children(hub, 1); - } hub_activate(hub); return 0; } -- cgit v1.2.3