Change since v7: Update date of adding new attributes' description Change since v5: Add usb_autopm_get/put_interface() around the port power operations in the control attribute's callback to deal with situation that control attribute is changed when the usb hub is suspended.
Change since v4: Add clear PORT_POWER if power policy is "off" in the hub_power_on(). Return -EIO if set/clear PORT_POWER fails in the store_port_power_control() This patch is to add two attributes for each usb hub ports to control port's power. Control port's power through setting or clearing PORT_POWER feature. control has two options. "auto", "on" and "off" "on" - port power must be on. "off" - port power must be off. state reports usb port's power state "on" - power on "off" - power off "error" - can't get power state Acked-by: Alan Stern <[email protected]> Signed-off-by: Lan Tianyu <[email protected]> --- Documentation/ABI/testing/sysfs-bus-usb | 24 ++++++ drivers/usb/core/hub.c | 133 ++++++++++++++++++++++++++++++- 2 files changed, 156 insertions(+), 1 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb index d5bb5be..479f94a 100644 --- a/Documentation/ABI/testing/sysfs-bus-usb +++ b/Documentation/ABI/testing/sysfs-bus-usb @@ -215,3 +215,27 @@ Contact: Lan Tianyu <[email protected]> Description: The /sys/bus/usb/devices/.../(hub interface)/portX is usb port device's sysfs directory. + +What: /sys/bus/usb/devices/.../(hub interface)/portX/control +Date: July 2012 +Contact: Lan Tianyu <[email protected]> +Description: + The /sys/bus/usb/devices/.../(hub interface)/portX/control + attribute allows user space to control the power policy on + the usb port. + + All ports have one of the following two values for control + "on" - port power must be on. + "off" - port power must be off. + +What: /sys/bus/usb/devices/.../(hub interface)/portX/state +Date: July 2012 +Contact: Lan Tianyu <[email protected]> +Description: + The /sys/bus/usb/devices/.../(hub interface)/portX/state + attribute allows user space to check hub port's power state. + + All ports have three following states + "on" - port power on + "off" - port power off + "error" - can't get the hub port's power state diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 375217f..12c7f14 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -37,11 +37,17 @@ #endif #endif +enum port_power_policy { + USB_PORT_POWER_ON = 0, + USB_PORT_POWER_OFF, +}; + struct usb_port { struct usb_device *child; struct device dev; struct dev_state *port_owner; enum usb_port_connect_type connect_type; + enum port_power_policy port_power_policy; }; struct usb_hub { @@ -95,6 +101,10 @@ struct device_type usb_port_device_type = { .name = "usb_port", }; +static const char on_string[] = "on"; +static const char off_string[] = "off"; +static const struct attribute_group *port_dev_group[]; + static inline int hub_is_superspeed(struct usb_device *hdev) { return (hdev->descriptor.bDeviceProtocol == USB_HUB_PR_SS); @@ -847,7 +857,12 @@ static unsigned hub_power_on(struct usb_hub *hub, bool do_delay) dev_dbg(hub->intfdev, "trying to enable port power on " "non-switchable hub\n"); for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++) - set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER); + if (hub->ports[port1 - 1]->port_power_policy + == USB_PORT_POWER_ON) + set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER); + else + clear_port_feature(hub->hdev, port1, + USB_PORT_FEAT_POWER); /* Wait at least 100 msec for power to become stable */ delay = max(pgood_delay, (unsigned) 100); @@ -1260,6 +1275,7 @@ static int usb_hub_create_port_device(struct usb_hub *hub, hub->ports[port1 - 1] = port_dev; port_dev->dev.parent = hub->intfdev; + port_dev->dev.groups = port_dev_group; port_dev->dev.type = &usb_port_device_type; port_dev->dev.release = usb_port_device_release; dev_set_name(&port_dev->dev, "port%d", port1); @@ -2609,6 +2625,25 @@ static int port_is_power_on(struct usb_hub *hub, unsigned portstatus) return ret; } +static int usb_get_hub_port_power_state(struct usb_device *hdev, int port1) +{ + struct usb_hub *hub = hdev_to_hub(hdev); + struct usb_port_status data; + u16 portstatus; + int ret; + + ret = get_port_status(hub->hdev, port1, &data); + if (ret < 4) { + dev_err(hub->intfdev, + "%s failed (err = %d)\n", __func__, ret); + if (ret >= 0) + ret = -EIO; + return ret; + } else + portstatus = le16_to_cpu(data.wPortStatus); + return port_is_power_on(hub, portstatus); +} + #ifdef CONFIG_PM /* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */ @@ -4550,6 +4585,102 @@ static int hub_thread(void *__unused) return 0; } +static ssize_t show_port_power_state(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct usb_device *udev = to_usb_device(dev->parent->parent); + struct usb_interface *intf = to_usb_interface(dev->parent); + int port1, power_state; + const char *result; + + sscanf(dev_name(dev), "port%d", &port1); + usb_autopm_get_interface(intf); + power_state = usb_get_hub_port_power_state(udev, port1); + usb_autopm_put_interface(intf); + if (power_state == 1) + result = on_string; + else if (!power_state) + result = off_string; + else + result = "error"; + return sprintf(buf, "%s\n", result); +} +static DEVICE_ATTR(state, S_IRUGO, show_port_power_state, NULL); + +static ssize_t show_port_power_control(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct usb_port *hub_port = to_usb_port(dev); + const char *result; + + switch (hub_port->port_power_policy) { + case USB_PORT_POWER_ON: + result = on_string; + break; + case USB_PORT_POWER_OFF: + result = off_string; + break; + default: + return -EINVAL; + } + return sprintf(buf, "%s\n", result); +} + +static ssize_t store_port_power_control(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + struct usb_device *hdev = to_usb_device(dev->parent->parent); + struct usb_interface *intf = to_usb_interface(dev->parent); + struct usb_port *hub_port = to_usb_port(dev); + int port1, ret, len = count; + char *cp; + + sscanf(dev_name(dev), "port%d", &port1); + cp = memchr(buf, '\n', count); + if (cp) + len = cp - buf; + if (len == sizeof on_string - 1 + && strncmp(buf, on_string, len) == 0) { + hub_port->port_power_policy = USB_PORT_POWER_ON; + usb_autopm_get_interface(intf); + ret = set_port_feature(hdev, port1, USB_PORT_FEAT_POWER); + usb_autopm_put_interface(intf); + if (ret < 0) + return -EIO; + } else if (len == sizeof off_string - 1 + && strncmp(buf, off_string, len) == 0) { + struct usb_hub *hub = hdev_to_hub(hdev); + + hub_port->port_power_policy = USB_PORT_POWER_OFF; + usb_autopm_get_interface(intf); + hub_port_logical_disconnect(hub, port1); + ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_POWER); + usb_autopm_put_interface(intf); + if (ret < 0) + return -EIO; + } else + return -EINVAL; + + return count; +} +static DEVICE_ATTR(control, S_IWUSR | S_IRUGO, show_port_power_control, + store_port_power_control); + +static struct attribute *port_dev_attrs[] = { + &dev_attr_control.attr, + &dev_attr_state.attr, + NULL, +}; + +static struct attribute_group port_dev_attr_grp = { + .attrs = port_dev_attrs, +}; + +static const struct attribute_group *port_dev_group[] = { + &port_dev_attr_grp, + NULL, +}; + static const struct usb_device_id hub_id_table[] = { { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS, .bDeviceClass = USB_CLASS_HUB}, -- 1.7.6.rc2.8.g28eb -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
