greybus: svc: add intf_eject attribute
Add a new write-only svc attribute to send an eject request to the svc
giving the interface number.
So, doing:
echo 3 > /sys/bus/greybus/devices/1-svc/intf_eject
will force eject the module on interface 3 (module slot 1 on EVT1).
This can take some seconds as the pulse width for module release is
large.
Signed-off-by: Rui Miguel Silva <rui.silva@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Reviewed-by: Jeffrey Carlyle <jcarlyle@google.com>
diff --git a/drivers/staging/greybus/svc.c b/drivers/staging/greybus/svc.c
index ef10b67..be62d30 100644
--- a/drivers/staging/greybus/svc.c
+++ b/drivers/staging/greybus/svc.c
@@ -40,9 +40,38 @@
}
static DEVICE_ATTR_RO(ap_intf_id);
+
+// FIXME
+// This is a hack, we need to do this "right" and clean the interface up
+// properly, not just forcibly yank the thing out of the system and hope for the
+// best. But for now, people want their modules to come out without having to
+// throw the thing to the ground or get out a screwdriver.
+static ssize_t intf_eject_store(struct device *dev,
+ struct device_attribute *attr, const char *buf,
+ size_t len)
+{
+ struct gb_svc *svc = to_gb_svc(dev);
+ unsigned short intf_id;
+ int ret;
+
+ ret = kstrtou16(buf, 10, &intf_id);
+ if (ret < 0)
+ return ret;
+
+ dev_warn(dev, "Forcibly trying to eject interface %d\n", intf_id);
+
+ ret = gb_svc_intf_eject(svc, intf_id);
+ if (ret < 0)
+ return ret;
+
+ return len;
+}
+static DEVICE_ATTR_WO(intf_eject);
+
static struct attribute *svc_attrs[] = {
&dev_attr_endo_id.attr,
&dev_attr_ap_intf_id.attr,
+ &dev_attr_intf_eject.attr,
NULL,
};
ATTRIBUTE_GROUPS(svc);