On Fri, 4 Jan 2013, Lan Tianyu wrote:
> This patch is to add usb port auto power off mechanism.
> When usb device is suspending, usb core will suspend usb port and
> usb port runtime pm callback will clear PORT_POWER feature to
> power off port if all conditions were met. These conditions are
> remote wakeup disable, pm qos NO_POWER_OFF flag clear and persist
> enable. When it resumes, power on port again. Add did_runtime_put
> in the struct usb_port in order to call pm_runtime_get/put(portdev)
> paired during suspending and resuming.
> --- a/drivers/usb/core/hub.c
> +++ b/drivers/usb/core/hub.c
> @@ -718,6 +719,9 @@ int usb_hub_set_port_power(struct usb_device *hdev, int port1,
> bool set)
> {
> int ret;
> + struct usb_hub *hub = hdev_to_hub(hdev);
> + struct usb_port *port_dev
> + = hub->ports[port1 - 1];
Unnecessary line break.
> @@ -2862,6 +2880,20 @@ int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
> udev->port_is_suspended = 1;
> msleep(10);
> }
> +
> + /*
> + * Check whether current status is meeting requirement of
> + * usb port power off mechanism
> + */
> + if (!udev->do_remote_wakeup
> + && (dev_pm_qos_flags(&port_dev->dev,
> + PM_QOS_FLAG_NO_POWER_OFF) != PM_QOS_FLAGS_ALL)
> + && udev->persist_enabled
> + && !status) {
> + pm_runtime_put_sync(&port_dev->dev);
> + port_dev->did_runtime_put = true;
You forgot to check port_dev->did_runtime_put in usb_disconnect.
Unless you check it, you could end up calling pm_runtime_put a second
time.
> --- a/drivers/usb/core/port.c
> +++ b/drivers/usb/core/port.c
> @@ -84,13 +109,22 @@ static int usb_port_runtime_suspend(struct device *dev)
> struct usb_port *port_dev = to_usb_port(dev);
> struct usb_device *hdev =
> to_usb_device(dev->parent->parent);
> + struct usb_hub *hub = hdev_to_hub(hdev);
> + int port1 = port_dev->portnum;
> + int retval;
>
> if (dev_pm_qos_flags(&port_dev->dev, PM_QOS_FLAG_NO_POWER_OFF)
> == PM_QOS_FLAGS_ALL)
> return -EAGAIN;
>
> - return usb_hub_set_port_power(hdev, port_dev->portnum,
> - false);
> + set_bit(port1, hub->busy_bits);
> + retval = usb_hub_set_port_power(hdev, port1, false);
> + clear_port_feature(hdev, port1,
> + USB_PORT_FEAT_C_CONNECTION);
> + clear_port_feature(hdev, port1,
> + USB_PORT_FEAT_C_ENABLE);
> + clear_bit(port1, hub->busy_bits);
> + return retval;
> }
Several unnecessary line breaks.
Alan Stern
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