USB: Composite framework: Add suspended sysfs entry

This patch adds a sysfs entry (/sys/devices/platform/_UDC_/gadget/suspended) to
show the suspend state of an USB composite gadget.

Signed-off-by: Fabien Chouteau <fabien.chouteau@barco.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 21 insertions, 0 deletions

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 5465d8767f9a..f9aff1bbcb3e 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -898,6 +898,18 @@ static void composite_disconnect(struct usb_gadget *gadget)
 
 /*-------------------------------------------------------------------------*/
 
+static ssize_t composite_show_suspended(struct device *dev,
+                                        struct device_attribute *attr,
+                                        char *buf)
+{
+        struct usb_gadget *gadget = dev_to_usb_gadget(dev);
+        struct usb_composite_dev *cdev = get_gadget_data(gadget);
+
+        return sprintf(buf, "%d\n", cdev->suspended);
+}
+
+static DEVICE_ATTR(suspended, 0444, composite_show_suspended, NULL);
+
 static void /* __init_or_exit */
 composite_unbind(struct usb_gadget *gadget)
 {
@@ -944,6 +956,7 @@ composite_unbind(struct usb_gadget *gadget)
         }
         kfree(cdev);
         set_gadget_data(gadget, NULL);
+        device_remove_file(&gadget->dev, &dev_attr_suspended);
         composite = NULL;
 }
 
@@ -1036,6 +1049,10 @@ static int __init composite_bind(struct usb_gadget *gadget)
                 string_override(composite->strings,
                         cdev->desc.iSerialNumber, iSerialNumber);
 
+        status = device_create_file(&gadget->dev, &dev_attr_suspended);
+        if (status)
+                goto fail;
+
         INFO(cdev, "%s ready\n", composite->name);
         return 0;
 
@@ -1064,6 +1081,8 @@ composite_suspend(struct usb_gadget *gadget)
         }
         if (composite->suspend)
                 composite->suspend(cdev);
+
+        cdev->suspended = 1;
 }
 
 static void
@@ -1084,6 +1103,8 @@ composite_resume(struct usb_gadget *gadget)
                                 f->resume(f);
                 }
         }
+
+        cdev->suspended = 0;
 }
 
 /*-------------------------------------------------------------------------*/