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>
This commit is contained in:
Rui Miguel Silva 2016-01-11 13:46:33 +00:00 committed by Greg Kroah-Hartman
parent c5d55fb359
commit 2c92bd5235
2 changed files with 37 additions and 0 deletions

View File

@ -142,6 +142,14 @@ Description:
defined by the Endo layout scheme, documented in
the ARA Module Developer Kit.
What: /sys/bus/greybus/device/N-svc/intf_eject
Date: October 2015
KernelVersion: 4.XX
Contact: Greg Kroah-Hartman <greg@kroah.com>
Description:
Write the number of the interface that you wish to
forcibly eject from the system.
What: /sys/bus/greybus/device/N-svc/unique_id
Date: October 2015
KernelVersion: 4.XX

View File

@ -40,9 +40,38 @@ static ssize_t ap_intf_id_show(struct device *dev,
}
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);