kernel/linux.git/include/linux/device.h, branch v2.6.34

Driver core: create lock/unlock functions for struct device

2010-03-08T01:04:52+00:00

In the future, we are going to be changing the lock type for struct device (once we get the lockdep infrastructure properly worked out) To make that changeover easier, and to possibly burry the lock in a different part of struct device, let's create some functions to lock and unlock a device so that no out-of-core code needs to be changed in the future. This patch creates the device_lock/unlock/trylock() functions, and converts all in-tree users to them. Cc: Thomas Gleixner Cc: Jean Delvare Cc: Dave Young Cc: Ming Lei Cc: Jiri Kosina Cc: Phil Carmody Cc: Arjan van de Ven Cc: Cornelia Huck Cc: Rafael J. Wysocki Cc: Pavel Machek Cc: Len Brown Cc: Magnus Damm Cc: Alan Stern Cc: Randy Dunlap Cc: Stefan Richter Cc: David Brownell Cc: Vegard Nossum Cc: Jesse Barnes Cc: Alex Chiang Cc: Kenji Kaneshige Cc: Andrew Morton Cc: Andrew Patterson Cc: Yu Zhao Cc: Dominik Brodowski Cc: Samuel Ortiz Cc: Wolfram Sang Cc: CHENG Renquan Cc: Oliver Neukum Cc: Frans Pop Cc: David Vrabel Cc: Kay Sievers Cc: Sarah Sharp Signed-off-by: Greg Kroah-Hartman

driver core: Add class_attr_string for simple read-only string

2010-03-08T01:04:48+00:00

Several drivers just export a static string as class attributes. Use the new extensible attribute support to define a simple CLASS_ATTR_STRING() macro for this. This will allow to remove code from drivers in followon patches. Signed-off-by: Andi Kleen Signed-off-by: Greg Kroah-Hartman

driver-core: Add attribute argument to class_attribute show/store

2010-03-08T01:04:48+00:00

Passing the attribute to the low level IO functions allows all kinds of cleanups, by sharing low level IO code without requiring an own function for every piece of data. Also drivers can extend the attributes with own data fields and use that in the low level function. This makes the class attributes the same as sysdev_class attributes and plain attributes. This will allow further cleanups in drivers. Full tree sweep converting all users. Signed-off-by: Andi Kleen Signed-off-by: Greg Kroah-Hartman

PM: Add facility for advanced testing of async suspend/resume

2010-02-26T19:39:10+00:00

Add configuration switch CONFIG_PM_ADVANCED_DEBUG for compiling in extra PM debugging/testing code allowing one to access some PM-related attributes of devices from the user space via sysfs. If CONFIG_PM_ADVANCED_DEBUG is set, add sysfs attribute power/async for every device allowing the user space to access the device's power.async_suspend flag and modify it, if desired. Signed-off-by: Rafael J. Wysocki

PM: Asynchronous suspend and resume of devices

2010-02-26T19:39:09+00:00

Theoretically, the total time of system sleep transitions (suspend to RAM, hibernation) can be reduced by running suspend and resume callbacks of device drivers in parallel with each other. However, there are dependencies between devices such that we're not allowed to suspend the parent of a device before suspending the device itself. Analogously, we're not allowed to resume a device before resuming its parent. The most straightforward way to take these dependencies into accout is to start the async threads used for suspending and resuming devices at the core level, so that async_schedule() is called for each suspend and resume callback supposed to be executed asynchronously. For this purpose, introduce a new device flag, power.async_suspend, used to mark the devices whose suspend and resume callbacks are to be executed asynchronously (ie. in parallel with the main suspend/resume thread and possibly in parallel with each other) and helper function device_enable_async_suspend() allowing one to set power.async_suspend for given device (power.async_suspend is unset by default for all devices). For each device with the power.async_suspend flag set the PM core will use async_schedule() to execute its suspend and resume callbacks. The async threads started for different devices as a result of calling async_schedule() are synchronized with each other and with the main suspend/resume thread with the help of completions, in the following way: (1) There is a completion, power.completion, for each device object. (2) Each device's completion is reset before calling async_schedule() for the device or, in the case of devices with the power.async_suspend flags unset, before executing the device's suspend and resume callbacks. (3) During suspend, right before running the bus type, device type and device class suspend callbacks for the device, the PM core waits for the completions of all the device's children to be completed. (4) During resume, right before running the bus type, device type and device class resume callbacks for the device, the PM core waits for the completion of the device's parent to be completed. (5) The PM core completes power.completion for each device right after the bus type, device type and device class suspend (or resume) callbacks executed for the device have returned. Signed-off-by: Rafael J. Wysocki

Driver core: driver_attribute parameters can often be const*

2009-12-23T19:23:43+00:00

Many struct driver_attribute descriptors are purely read-only structures, and there's no need to change them. Therefore make the promise not to, which will let those descriptors be put in a ro section. Signed-off-by: Phil Carmody Signed-off-by: Greg Kroah-Hartman

Driver core: bin_attribute parameters can often be const*

2009-12-23T19:23:43+00:00

Many struct bin_attribute descriptors are purely read-only structures, and there's no need to change them. Therefore make the promise not to, which will let those descriptors be put in a ro section. Signed-off-by: Phil Carmody Signed-off-by: Greg Kroah-Hartman

Driver core: device_attribute parameters can often be const*

2009-12-23T19:23:43+00:00

Most device_attributes are const, and are begging to be put in a ro section. However, the create and remove file interfaces were failing to propagate the const promise which the only functions they call offer. Signed-off-by: Phil Carmody Signed-off-by: Greg Kroah-Hartman

Driver Core: devtmpfs: use sys_mount()

2009-12-11T19:24:51+00:00

Signed-off-by: Kay Sievers Signed-off-by: Greg Kroah-Hartman

Driver core: allow certain drivers prohibit bind/unbind via sysfs

2009-10-30T21:59:51+00:00

Platform drivers registered via platform_driver_probe() can be bound to devices only once, upon registration, because discard their probe() routines to save memory. Unbinding the driver through sysfs 'unbind' leaves the device stranded and confuses users so let's not create bind and unbind attributes for such drivers. Signed-off-by: Dmitry Torokhov Cc: Éric Piel Signed-off-by: Greg Kroah-Hartman