The reset_resume implementation is in place to recover lost power
sessions. Testing has already shown that simply waiting for
USB_PORT_STAT_C_CONNECTION is not sufficient for recovering a powered
down port. Replace recovery actions in usb_port_runtime_resume() with a
deferral to recovery via usb_port_resume().
>From the point the port is powered down to the point that the port is
recovered we do not want khubd or hub_activate() to take action on the
disabled port. Introduce hub->poweroff_bits to communicate that the
port is not to be serviced until it has been through recovery.
The existing ->power_is_on flag gates hub_activate() from setting change
bits. Placing the evalaution of the power state there is insufficient
for guaranteeing that khubd does not receive a connection change event.
Also, hub_activate() in this case is only running on hub_resume() we
want to manage change events as individual ports resume. ->power_is_on
will be removed in a subsequent patch.
Signed-off-by: Dan Williams <dan.j.willi...@intel.com>
---
drivers/usb/core/hub.c | 22 +++++++++++++++++-----
drivers/usb/core/hub.h | 16 +---------------
drivers/usb/core/port.c | 29 +++++++++--------------------
3 files changed, 27 insertions(+), 40 deletions(-)
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 06cec635e703..6f2cf4672942 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1092,6 +1092,9 @@ static void hub_activate(struct usb_hub *hub, enum
hub_activation_type type)
struct usb_device *udev = hub->ports[port1 - 1]->child;
u16 portstatus, portchange;
+ if (test_bit(port1, hub->poweroff_bits))
+ continue;
+
portstatus = portchange = 0;
status = hub_port_status(hub, port1, &portstatus, &portchange);
if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
@@ -2783,8 +2786,14 @@ static int check_port_resume_type(struct usb_device
*udev,
struct usb_hub *hub, int port1,
int status, unsigned portchange, unsigned portstatus)
{
+ /* port power recovery, proceed to resetting the device */
+ if (test_bit(port1, hub->poweroff_bits)) {
+ status = 0;
+ udev->reset_resume = 1;
+ }
+
/* Is the device still present? */
- if (status || port_is_suspended(hub, portstatus) ||
+ else if (status || port_is_suspended(hub, portstatus) ||
!port_is_power_on(hub, portstatus) ||
!(portstatus & USB_PORT_STAT_CONNECTION)) {
if (status >= 0)
@@ -3871,7 +3880,7 @@ EXPORT_SYMBOL_GPL(usb_enable_ltm);
* every 25ms for transient disconnects. When the port status has been
* unchanged for 100ms it returns the port status.
*/
-int hub_port_debounce(struct usb_hub *hub, int port1, bool must_be_connected)
+int hub_port_debounce(struct usb_hub *hub, int port1)
{
int ret;
int total_time, stable_time = 0;
@@ -3885,8 +3894,7 @@ int hub_port_debounce(struct usb_hub *hub, int port1,
bool must_be_connected)
if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
(portstatus & USB_PORT_STAT_CONNECTION) == connection) {
- if (!must_be_connected ||
- (connection == USB_PORT_STAT_CONNECTION))
+ if (connection == USB_PORT_STAT_CONNECTION)
stable_time += HUB_DEBOUNCE_STEP;
if (stable_time >= HUB_DEBOUNCE_STABLE)
break;
@@ -4437,7 +4445,7 @@ static void hub_port_connect_change(struct usb_hub *hub,
int port1,
if (portchange & (USB_PORT_STAT_C_CONNECTION |
USB_PORT_STAT_C_ENABLE)) {
- status = hub_port_debounce_be_stable(hub, port1);
+ status = hub_port_debounce(hub, port1);
if (status < 0) {
if (status != -ENODEV && printk_ratelimit())
dev_err(hub_dev, "connect-debounce failed, "
@@ -4749,6 +4757,9 @@ static void hub_events(void)
connect_change = 1;
}
+ if (test_bit(i, hub->poweroff_bits))
+ continue;
+
if (portchange & USB_PORT_STAT_C_ENABLE) {
if (!connect_change)
dev_dbg (hub_dev,
@@ -5155,6 +5166,7 @@ static int usb_reset_and_verify_device(struct usb_device
*udev)
if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
break;
}
+ clear_bit(port1, parent_hub->poweroff_bits);
clear_bit(port1, parent_hub->busy_bits);
if (ret < 0)
diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h
index 4e4790dea343..0b9bde67ff8b 100644
--- a/drivers/usb/core/hub.h
+++ b/drivers/usb/core/hub.h
@@ -47,6 +47,7 @@ struct usb_hub {
status change */
unsigned long busy_bits[1]; /* ports being reset or
resumed */
+ unsigned long poweroff_bits[1]; /* ports logically off */
unsigned long removed_bits[1]; /* ports with a "removed"
device present */
unsigned long wakeup_bits[1]; /* ports that have signaled
@@ -106,20 +107,5 @@ extern void usb_hub_remove_port_device(struct usb_hub *hub,
extern int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
int port1, bool set);
extern struct usb_hub *usb_hub_to_struct_hub(struct usb_device *hdev);
-extern int hub_port_debounce(struct usb_hub *hub, int port1,
- bool must_be_connected);
extern int usb_clear_port_feature(struct usb_device *hdev,
int port1, int feature);
-
-static inline int hub_port_debounce_be_connected(struct usb_hub *hub,
- int port1)
-{
- return hub_port_debounce(hub, port1, true);
-}
-
-static inline int hub_port_debounce_be_stable(struct usb_hub *hub,
- int port1)
-{
- return hub_port_debounce(hub, port1, false);
-}
-
diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
index 51542f852393..0ecff7d85739 100644
--- a/drivers/usb/core/port.c
+++ b/drivers/usb/core/port.c
@@ -83,26 +83,13 @@ static int usb_port_runtime_resume(struct device *dev)
return -EINVAL;
usb_autopm_get_interface(intf);
- set_bit(port1, hub->busy_bits);
-
retval = usb_hub_set_port_power(hdev, hub, port1, true);
- if (port_dev->child && !retval) {
- /*
- * Attempt to wait for usb hub port to be reconnected in order
- * to make the resume procedure successful. The device may have
- * disconnected while the port was powered off, so ignore the
- * return status.
- */
- retval = hub_port_debounce_be_connected(hub, port1);
- if (retval < 0)
- dev_dbg(&port_dev->dev, "can't get reconnection after
setting port power on, status %d\n",
- retval);
- usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
- retval = 0;
- }
-
- clear_bit(port1, hub->busy_bits);
usb_autopm_put_interface(intf);
+
+ /* no child? we're done recovering this port */
+ if (!port_dev->child)
+ clear_bit(port1, hub->poweroff_bits);
+
return retval;
}
@@ -122,13 +109,15 @@ static int usb_port_runtime_suspend(struct device *dev)
== PM_QOS_FLAGS_ALL)
return -EAGAIN;
+ set_bit(port1, hub->poweroff_bits);
usb_autopm_get_interface(intf);
- set_bit(port1, hub->busy_bits);
retval = usb_hub_set_port_power(hdev, hub, port1, false);
+ if (retval)
+ clear_bit(port1, hub->poweroff_bits);
usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
- clear_bit(port1, hub->busy_bits);
usb_autopm_put_interface(intf);
+
return retval;
}
#endif
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