user/sven/linux.git/drivers/base/base.h, branch v3.4.92

driver core: move the deferred probe pointer into the private area

2012-03-08T20:17:22Z

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

drivercore: Add driver probe deferral mechanism

2012-03-08T19:53:13Z

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

cpu: Do not return errors from cpu_dev_init() which will be ignored

2012-01-11T23:49:43Z

cpu_dev_init() is only called from driver_init(), which does not check its return value. Therefore make cpu_dev_init() return void. We must register the CPU subsystem, so panic if this fails. If sched_create_sysfs_power_savings_entries() fails, the damage is contained, so ignore this (as before). Signed-off-by: Ben Hutchings Signed-off-by: Linus Torvalds

driver-core: implement 'sysdev' functionality for regular devices and buses

2011-12-14T22:29:38Z

All sysdev classes and sysdev devices will converted to regular devices and buses to properly hook userspace into the event processing. There is no interesting difference between a 'sysdev' and 'device' which would justify to roll an entire own subsystem with different userspace export semantics. Userspace relies on events and generic sysfs subsystem infrastructure from sysdev devices, which are currently not properly available. Every converted sysdev class will create a regular device with the class name in /sys/devices/system and all registered devices will becom a children of theses devices. For compatibility reasons, the sysdev class-wide attributes are created at this parent device. (Do not copy that logic for anything new, subsystem- wide properties belong to the subsystem, not to some fake parent device created in /sys/devices.) Every sysdev driver is implemented as a simple subsystem interface now, and no longer called a driver. After all sysdev classes are ported to regular driver core entities, the sysdev implementation will be entirely removed from the kernel. Signed-off-by: Kay Sievers Signed-off-by: Greg Kroah-Hartman

drivers/base: base.h implicitly depends on

2011-10-31T23:31:39Z

This file is currently relying on sneaking it in through the implicit include paths from device.h. Once that is cleaned up, this will happen: In file included from drivers/base/init.c:12: drivers/base/base.h:34: error: field ‘bus_notifier’ has incomplete type make[3]: *** [drivers/base/init.o] Error 1 Fix it up in advance, so the cleanup can continue. Signed-off-by: Paul Gortmaker

PM: Remove sysdev suspend, resume and shutdown operations

2011-05-11T19:37:15Z

Since suspend, resume and shutdown operations in struct sysdev_class and struct sysdev_driver are not used any more, remove them. Also drop sysdev_suspend(), sysdev_resume() and sysdev_shutdown() used for executing those operations and modify all of their users accordingly. This reduces kernel code size quite a bit and reduces its complexity. Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman

driver-core: merge private parts of class and bus

2010-11-17T22:21:08Z

As classes and busses are pretty much the same thing, and we want to merge them together into a 'subsystem' in the future, let us share the same private data parts to make that merge easier. Signed-off-by: Kay Sievers Signed-off-by: Greg Kroah-Hartman

Driver Core: devtmpfs - kernel-maintained tmpfs-based /dev

2009-09-15T16:50:49Z

Devtmpfs lets the kernel create a tmpfs instance called devtmpfs very early at kernel initialization, before any driver-core device is registered. Every device with a major/minor will provide a device node in devtmpfs. Devtmpfs can be changed and altered by userspace at any time, and in any way needed - just like today's udev-mounted tmpfs. Unmodified udev versions will run just fine on top of it, and will recognize an already existing kernel-created device node and use it. The default node permissions are root:root 0600. Proper permissions and user/group ownership, meaningful symlinks, all other policy still needs to be applied by userspace. If a node is created by devtmps, devtmpfs will remove the device node when the device goes away. If the device node was created by userspace, or the devtmpfs created node was replaced by userspace, it will no longer be removed by devtmpfs. If it is requested to auto-mount it, it makes init=/bin/sh work without any further userspace support. /dev will be fully populated and dynamic, and always reflect the current device state of the kernel. With the commonly used dynamic device numbers, it solves the problem where static devices nodes may point to the wrong devices. It is intended to make the initial bootup logic simpler and more robust, by de-coupling the creation of the inital environment, to reliably run userspace processes, from a complex userspace bootstrap logic to provide a working /dev. Signed-off-by: Kay Sievers Signed-off-by: Jan Blunck Tested-By: Harald Hoyer Tested-By: Scott James Remnant Signed-off-by: Greg Kroah-Hartman

Driver core: move dev_get/set_drvdata to drivers/base/dd.c

2009-09-15T16:50:47Z

No one should directly access the driver_data field, so remove the field and make it private. We dynamically create the private field now if it is needed, to handle drivers that call get/set before they are registered with the driver core. Also update the copyright notices on these files while we are there. Cc: Kay Sievers Signed-off-by: Greg Kroah-Hartman

Driver core: add new device to bus's list before probing

2009-09-15T16:50:46Z

This patch (as1271) affects when new devices get linked into their bus's list of devices. Currently this happens after probing, and it doesn't happen at all if probing fails. Clearly this is wrong, because at that point quite a few symbolic links have already been created in sysfs. We are committed to adding the device, so it should be linked into the bus's list regardless. In addition, this needs to happen before the uevent announcing the new device gets issued. Otherwise user programs might try to access the device before it has been added to the bus. To fix both these problems, the patch moves the call to klist_add_tail() forward from bus_attach_device() to bus_add_device(). Since bus_attach_device() now does nothing but probe for drivers, it has been renamed to bus_probe_device(). And lastly, the kerneldoc is updated. Signed-off-by: Alan Stern CC: Kay Sievers Signed-off-by: Greg Kroah-Hartman