diff --git a/Documentation/ABI/testing/sysfs-devices-waiting_for_supplier b/Documentation/ABI/testing/sysfs-devices-waiting_for_supplier new file mode 100644 index 000000000000..59d073d20db6 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-devices-waiting_for_supplier @@ -0,0 +1,17 @@ +What: /sys/devices/.../waiting_for_supplier +Date: May 2020 +Contact: Saravana Kannan +Description: + The /sys/devices/.../waiting_for_supplier attribute is only + present when fw_devlink kernel command line option is enabled + and is set to something stricter than "permissive". It is + removed once a device probes successfully (because the + information is no longer relevant). The number read from it (0 + or 1) reflects whether the device is waiting for one or more + suppliers to be added and then linked to using device links + before the device can probe. + + A value of 0 means the device is not waiting for any suppliers + to be added before it can probe. A value of 1 means the device + is waiting for one or more suppliers to be added before it can + probe. diff --git a/drivers/base/core.c b/drivers/base/core.c index ca6403343515..5373ddd029f6 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -1041,6 +1041,22 @@ static void device_link_drop_managed(struct device_link *link) kref_put(&link->kref, __device_link_del); } +static ssize_t waiting_for_supplier_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + bool val; + + device_lock(dev); + mutex_lock(&wfs_lock); + val = !list_empty(&dev->links.needs_suppliers) + && dev->links.need_for_probe; + mutex_unlock(&wfs_lock); + device_unlock(dev); + return sprintf(buf, "%u\n", val); +} +static DEVICE_ATTR_RO(waiting_for_supplier); + /** * device_links_driver_bound - Update device links after probing its driver. * @dev: Device to update the links for. @@ -1065,6 +1081,7 @@ void device_links_driver_bound(struct device *dev) mutex_lock(&wfs_lock); list_del_init(&dev->links.needs_suppliers); mutex_unlock(&wfs_lock); + device_remove_file(dev, &dev_attr_waiting_for_supplier); device_links_write_lock(); @@ -2144,8 +2161,16 @@ static int device_add_attrs(struct device *dev) goto err_remove_dev_groups; } + if (fw_devlink_flags && !fw_devlink_is_permissive()) { + error = device_create_file(dev, &dev_attr_waiting_for_supplier); + if (error) + goto err_remove_dev_online; + } + return 0; + err_remove_dev_online: + device_remove_file(dev, &dev_attr_online); err_remove_dev_groups: device_remove_groups(dev, dev->groups); err_remove_type_groups: @@ -2163,6 +2188,7 @@ static void device_remove_attrs(struct device *dev) struct class *class = dev->class; const struct device_type *type = dev->type; + device_remove_file(dev, &dev_attr_waiting_for_supplier); device_remove_file(dev, &dev_attr_online); device_remove_groups(dev, dev->groups);