From 07d57a32fb6eb2da017796e038682f817a4f685e Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Wed, 1 Feb 2012 11:22:22 -0700 Subject: drivercore: Output common devicetree information in uevent When userspace needs to find a specific device, it currently isn't easy to resolve a /sys/devices/ path from a specific device tree node. Nor is it easy to obtain the compatible list for devices. This patch generalizes the code that inserts OF_* values into the uevent device attribute so that any device that is attached to an OF node will have that information exported to userspace. Without this patch only platform devices and some powerpc-specific busses have access to this data. The original function also creates a MODALIAS property for the compatible list, but that code has not been generalized into the common case because it has the potential to break module loading on a lot of bus types. Bus types are still responsible for their own MODALIAS properties. Boot tested on ARM and compile tested on PowerPC and SPARC. Signed-off-by: Grant Likely Acked-by: Greg Kroah-Hartman Cc: Tobias Klauser Cc: Frederic Lambert Cc: Rob Herring Cc: Mark Brown Cc: "David S. Miller" Cc: Benjamin Herrenschmidt --- drivers/base/core.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'drivers/base/core.c') diff --git a/drivers/base/core.c b/drivers/base/core.c index 4a67cc0c8b37..28d8c21bb323 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -18,6 +18,8 @@ #include #include #include +#include +#include #include #include #include @@ -267,6 +269,9 @@ static int dev_uevent(struct kset *kset, struct kobject *kobj, if (dev->driver) add_uevent_var(env, "DRIVER=%s", dev->driver->name); + /* Add common DT information about the device */ + of_device_uevent(dev, env); + /* have the bus specific function add its stuff */ if (dev->bus && dev->bus->uevent) { retval = dev->bus->uevent(dev, env); -- cgit v1.2.3 From d1c3414c2a9d10ef7f0f7665f5d2947cd088c093 Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Mon, 5 Mar 2012 08:47:41 -0700 Subject: drivercore: Add driver probe deferral mechanism Allow drivers to report at probe time that they cannot get all the resources required by the device, and should be retried at a later time. This should completely solve the problem of getting devices initialized in the right order. Right now this is mostly handled by mucking about with initcall ordering which is a complete hack, and doesn't even remotely handle the case where device drivers are in modules. This approach completely sidesteps the issues by allowing driver registration to occur in any order, and any driver can request to be retried after a few more other drivers get probed. v4: - Integrate Manjunath's addition of a separate workqueue - Change -EAGAIN to -EPROBE_DEFER for drivers to trigger deferral - Update comment blocks to reflect how the code really works v3: - Hold off workqueue scheduling until late_initcall so that the bulk of driver probes are complete before we start retrying deferred devices. - Tested with simple use cases. Still needs more testing though. Using it to get rid of the gpio early_initcall madness, or to replace the ASoC internal probe deferral code would be ideal. v2: - added locking so it should no longer be utterly broken in that regard - remove device from deferred list at device_del time. - Still completely untested with any real use case, but has been boot tested. Signed-off-by: Grant Likely Cc: Mark Brown Cc: Arnd Bergmann Cc: Dilan Lee Cc: Manjunath GKondaiah Cc: Alan Stern Cc: Tony Lindgren Cc: Alan Cox Reviewed-by: Mark Brown Acked-by: David Daney Reviewed-by: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/base/core.c') diff --git a/drivers/base/core.c b/drivers/base/core.c index 74dda4f697f9..d4ff7adce38c 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -644,6 +644,7 @@ void device_initialize(struct device *dev) { dev->kobj.kset = devices_kset; kobject_init(&dev->kobj, &device_ktype); + INIT_LIST_HEAD(&dev->deferred_probe); INIT_LIST_HEAD(&dev->dma_pools); mutex_init(&dev->mutex); lockdep_set_novalidate_class(&dev->mutex); @@ -1188,6 +1189,7 @@ void device_del(struct device *dev) device_remove_file(dev, &uevent_attr); device_remove_attrs(dev); bus_remove_device(dev); + driver_deferred_probe_del(dev); /* * Some platform devices are driven without driver attached -- cgit v1.2.3 From ef8a3fd6e5e12e8989dae97ba5491c2e39369af9 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Thu, 8 Mar 2012 12:17:22 -0800 Subject: driver core: move the deferred probe pointer into the private area Nothing outside of the driver core needs to get to the deferred probe pointer, so move it inside the private area of 'struct device' so no one tries to mess around with it. Cc: Grant Likely Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/base/core.c') diff --git a/drivers/base/core.c b/drivers/base/core.c index d4ff7adce38c..7050a75dde38 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -644,7 +644,6 @@ void device_initialize(struct device *dev) { dev->kobj.kset = devices_kset; kobject_init(&dev->kobj, &device_ktype); - INIT_LIST_HEAD(&dev->deferred_probe); INIT_LIST_HEAD(&dev->dma_pools); mutex_init(&dev->mutex); lockdep_set_novalidate_class(&dev->mutex); @@ -922,6 +921,7 @@ int device_private_init(struct device *dev) dev->p->device = dev; klist_init(&dev->p->klist_children, klist_children_get, klist_children_put); + INIT_LIST_HEAD(&dev->p->deferred_probe); return 0; } -- cgit v1.2.3