[PATCH v1 14/18] driver core: Use device's fwnode to check if it is waiting for suppliers

From: Saravana Kannan
Date: Wed Nov 04 2020 - 18:24:58 EST


To check if a device is still waiting for its supplier devices to be
added, we used to check if the devices is in a global
waiting_for_suppliers list. Since the global list will be deleted in
subsequent patches, this patch stops using this check.

Instead, this patch uses a more device specific check. It checks if the
device's fwnode has any fwnode links that haven't been converted to
device links yet.

Signed-off-by: Saravana Kannan <saravanak@xxxxxxxxxx>
---
drivers/base/core.c | 18 ++++++++----------
1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 4ae5f2885ac5..d51dd564add1 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -51,6 +51,7 @@ static DEFINE_MUTEX(wfs_lock);
static LIST_HEAD(deferred_sync);
static unsigned int defer_sync_state_count = 1;
static DEFINE_MUTEX(fwnode_link_lock);
+static bool fw_devlink_is_permissive(void);

/**
* fwnode_link_add - Create a link between two fwnode_handles.
@@ -994,13 +995,13 @@ int device_links_check_suppliers(struct device *dev)
* Device waiting for supplier to become available is not allowed to
* probe.
*/
- mutex_lock(&wfs_lock);
- if (!list_empty(&dev->links.needs_suppliers) &&
- dev->links.need_for_probe) {
- mutex_unlock(&wfs_lock);
+ mutex_lock(&fwnode_link_lock);
+ if (dev->fwnode && !list_empty(&dev->fwnode->suppliers) &&
+ !fw_devlink_is_permissive()) {
+ mutex_unlock(&fwnode_link_lock);
return -EPROBE_DEFER;
}
- mutex_unlock(&wfs_lock);
+ mutex_unlock(&fwnode_link_lock);

device_links_write_lock();

@@ -1166,10 +1167,7 @@ static ssize_t waiting_for_supplier_show(struct device *dev,
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);
+ val = !list_empty(&dev->fwnode->suppliers);
device_unlock(dev);
return sysfs_emit(buf, "%u\n", val);
}
@@ -2226,7 +2224,7 @@ static int device_add_attrs(struct device *dev)
goto err_remove_dev_groups;
}

- if (fw_devlink_flags && !fw_devlink_is_permissive()) {
+ if (fw_devlink_flags && !fw_devlink_is_permissive() && dev->fwnode) {
error = device_create_file(dev, &dev_attr_waiting_for_supplier);
if (error)
goto err_remove_dev_online;
--
2.29.1.341.ge80a0c044ae-goog