summaryrefslogtreecommitdiffstats
path: root/include/linux/device.h
diff options
context:
space:
mode:
authorLuis R. Rodriguez <mcgrof@suse.com>2015-03-30 16:20:06 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2015-05-20 00:25:25 -0700
commitd173a137c5bd95ee29d02705e5fa8890ef149718 (patch)
treec900140a59a822192090d8bded8a127316b8c556 /include/linux/device.h
parentf2411da746985e60d4d087f3a43e271c61785927 (diff)
downloadblackbird-op-linux-d173a137c5bd95ee29d02705e5fa8890ef149718.tar.gz
blackbird-op-linux-d173a137c5bd95ee29d02705e5fa8890ef149718.zip
driver-core: enable drivers to opt-out of async probe
There are drivers that can not be probed asynchronously. One such group is platform drivers registered with platform_driver_probe(), which expects driver's probe routine be discarded after the driver has been registered and initial binding attempt executed. Also platform_driver_probe() an error when no devices were bound to the driver, allowing failing to load such driver module altogether. Other drivers do not work well with asynchronous probing because of driver bug or not optimal driver organization. To allow using such drivers even when user requests asynchronous probing as default boot strategy, let's allow them to opt out. Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/device.h')
-rw-r--r--include/linux/device.h13
1 files changed, 7 insertions, 6 deletions
diff --git a/include/linux/device.h b/include/linux/device.h
index 77b7cd9e5467..00ac57c26615 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -201,15 +201,15 @@ extern struct klist *bus_get_device_klist(struct bus_type *bus);
* respective probe routines. This tells the core what to
* expect and prefer.
*
- * @PROBE_DEFAULT_STRATEGY: Drivers expect their probe routines
- * to run synchronously with driver and device registration
- * (with the exception of -EPROBE_DEFER handling - re-probing
- * always ends up being done asynchronously) unless user
- * explicitly requested asynchronous probing via module
- * parameter.
+ * @PROBE_DEFAULT_STRATEGY: Used by drivers that work equally well
+ * whether probed synchronously or asynchronously.
* @PROBE_PREFER_ASYNCHRONOUS: Drivers for "slow" devices which
* probing order is not essential for booting the system may
* opt into executing their probes asynchronously.
+ * @PROBE_FORCE_SYNCHRONOUS: Use this to annotate drivers that need
+ * their probe routines to run synchronously with driver and
+ * device registration (with the exception of -EPROBE_DEFER
+ * handling - re-probing always ends up being done asynchronously).
*
* Note that the end goal is to switch the kernel to use asynchronous
* probing by default, so annotating drivers with
@@ -220,6 +220,7 @@ extern struct klist *bus_get_device_klist(struct bus_type *bus);
enum probe_type {
PROBE_DEFAULT_STRATEGY,
PROBE_PREFER_ASYNCHRONOUS,
+ PROBE_FORCE_SYNCHRONOUS,
};
/**
OpenPOWER on IntegriCloud