[PATCH 1/2] driver-core: Add externally callable function to trigger deferred probes

From: Lee Jones
Date: Tue Jul 12 2016 - 12:20:34 EST


Deferred probes are currently only re-executed if new drivers are successfully
registered and probed. Drivers which defer their probes based on things like
missing firmware located on rootfs will sometimes only be re-probed if kernel
modules are found. Unfortunately, this is fragile and can not be guaranteed
or relied upon. This call allows us to trigger probe re-execution at any
point during boot. For instance after rootfs is mounted in order to collect
firmwares in rootfs.

Tested-by: Peter Griffin <peter.griffin@xxxxxxxxxx>
Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
---
drivers/base/dd.c | 8 ++++++++
include/linux/device.h | 1 +
2 files changed, 9 insertions(+)

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 16688f5..ab20851 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -203,6 +203,14 @@ void device_unblock_probing(void)
}

/**
+ * deferred_probe_tigger() - Trigger a deferred probe
+ */
+void deferred_probe_trigger(void)
+{
+ driver_deferred_probe_trigger();
+}
+
+/**
* deferred_probe_initcall() - Enable probing of deferred devices
*
* We don't want to get in the way when the bulk of drivers are getting probed.
diff --git a/include/linux/device.h b/include/linux/device.h
index 38f0281..d441471 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -293,6 +293,7 @@ extern struct device_driver *driver_find(const char *name,
struct bus_type *bus);
extern int driver_probe_done(void);
extern void wait_for_device_probe(void);
+extern void deferred_probe_trigger(void);


/* sysfs interface for exporting driver attributes */
--
2.9.0