Commit bcca686c authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
Browse files

Revert "driver core: Add sync_state driver/bus callback" 



This reverts commit 8f8184d6.

Based on a lot of email and in-person discussions, this patch series is
being reworked to address a number of issues that were pointed out that
needed to be taken care of before it should be merged.  It will be
resubmitted with those changes hopefully soon.

Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Saravana Kannan <saravanak@google.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 77df8e79

drivers/base/core.c

+0 −65
Original line number Diff line number Diff line
@@ -46,8 +46,6 @@ early_param("sysfs.deprecated", sysfs_deprecated_setup); 
/* Device links support. */

static LIST_HEAD(wait_for_suppliers);

static DEFINE_MUTEX(wfs_lock);

static LIST_HEAD(deferred_sync);

static unsigned int supplier_sync_state_disabled;



#ifdef CONFIG_SRCU

static DEFINE_MUTEX(device_links_lock);
@@ -653,62 +651,6 @@ int device_links_check_suppliers(struct device *dev) 
	return ret;

}



static void __device_links_supplier_sync_state(struct device *dev)

{

	struct device_link *link;



	if (dev->state_synced)

		return;



	list_for_each_entry(link, &dev->links.consumers, s_node) {

		if (!(link->flags & DL_FLAG_MANAGED))

			continue;

		if (link->status != DL_STATE_ACTIVE)

			return;

	}



	if (dev->bus->sync_state)

		dev->bus->sync_state(dev);

	else if (dev->driver && dev->driver->sync_state)

		dev->driver->sync_state(dev);



	dev->state_synced = true;

}



void device_links_supplier_sync_state_pause(void)

{

	device_links_write_lock();

	supplier_sync_state_disabled++;

	device_links_write_unlock();

}



void device_links_supplier_sync_state_resume(void)

{

	struct device *dev, *tmp;



	device_links_write_lock();

	if (!supplier_sync_state_disabled) {

		WARN(true, "Unmatched sync_state pause/resume!");

		goto out;

	}

	supplier_sync_state_disabled--;

	if (supplier_sync_state_disabled)

		goto out;



	list_for_each_entry_safe(dev, tmp, &deferred_sync, links.defer_sync) {

		__device_links_supplier_sync_state(dev);

		list_del_init(&dev->links.defer_sync);

	}

out:

	device_links_write_unlock();

}



static void __device_links_supplier_defer_sync(struct device *sup)

{

	if (list_empty(&sup->links.defer_sync))

		list_add_tail(&sup->links.defer_sync, &deferred_sync);

}



/**

 * device_links_driver_bound - Update device links after probing its driver.

 * @dev: Device to update the links for.
@@ -753,11 +695,6 @@ void device_links_driver_bound(struct device *dev) 


		WARN_ON(link->status != DL_STATE_CONSUMER_PROBE);

		WRITE_ONCE(link->status, DL_STATE_ACTIVE);



		if (supplier_sync_state_disabled)

			__device_links_supplier_defer_sync(link->supplier);

		else

			__device_links_supplier_sync_state(link->supplier);

	}



	dev->links.status = DL_DEV_DRIVER_BOUND;
@@ -874,7 +811,6 @@ void device_links_driver_cleanup(struct device *dev) 
		WRITE_ONCE(link->status, DL_STATE_DORMANT);

	}



	list_del_init(&dev->links.defer_sync);

	__device_links_no_driver(dev);



	device_links_write_unlock();
@@ -1849,7 +1785,6 @@ void device_initialize(struct device *dev) 
	INIT_LIST_HEAD(&dev->links.consumers);

	INIT_LIST_HEAD(&dev->links.suppliers);

	INIT_LIST_HEAD(&dev->links.needs_suppliers);

	INIT_LIST_HEAD(&dev->links.defer_sync);

	dev->links.status = DL_DEV_NO_DRIVER;

}

EXPORT_SYMBOL_GPL(device_initialize);

include/linux/device.h

+0 −26
Original line number Diff line number Diff line
@@ -84,8 +84,6 @@ extern void bus_remove_file(struct bus_type *, struct bus_attribute *); 
 *		available at the time this function is called.  As in, the

 *		function should NOT stop at the first failed device link if

 *		other unlinked supplier devices are present in the system.

 *		This is necessary for the sync_state() callback to work

 *		correctly.

 *

 *		Return 0 if device links have been successfully created to all

 *		the suppliers of this device.  Return an error if some of the
@@ -93,13 +91,6 @@ extern void bus_remove_file(struct bus_type *, struct bus_attribute *); 
 *		reattempted in the future.

 * @probe:	Called when a new device or driver add to this bus, and callback

 *		the specific driver's probe to initial the matched device.

 * @sync_state:	Called to sync device state to software state after all the

 *		state tracking consumers linked to this device (present at

 *		the time of late_initcall) have successfully bound to a

 *		driver. If the device has no consumers, this function will

 *		be called at late_initcall_sync level. If the device has

 *		consumers that are never bound to a driver, this function

 *		will never get called until they do.

 * @remove:	Called when a device removed from this bus.

 * @shutdown:	Called at shut-down time to quiesce the device.

 *
@@ -144,7 +135,6 @@ struct bus_type { 
	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);

	int (*add_links)(struct device *dev);

	int (*probe)(struct device *dev);

	void (*sync_state)(struct device *dev);

	int (*remove)(struct device *dev);

	void (*shutdown)(struct device *dev);
@@ -376,13 +366,6 @@ enum probe_type { 
 * @probe:	Called to query the existence of a specific device,

 *		whether this driver can work with it, and bind the driver

 *		to a specific device.

 * @sync_state:	Called to sync device state to software state after all the

 *		state tracking consumers linked to this device (present at

 *		the time of late_initcall) have successfully bound to a

 *		driver. If the device has no consumers, this function will

 *		be called at late_initcall_sync level. If the device has

 *		consumers that are never bound to a driver, this function

 *		will never get called until they do.

 * @remove:	Called when the device is removed from the system to

 *		unbind a device from this driver.

 * @shutdown:	Called at shut-down time to quiesce the device.
@@ -423,7 +406,6 @@ struct device_driver { 


	int (*edit_links)(struct device *dev);

	int (*probe) (struct device *dev);

	void (*sync_state)(struct device *dev);

	int (*remove) (struct device *dev);

	void (*shutdown) (struct device *dev);

	int (*suspend) (struct device *dev, pm_message_t state);
@@ -1177,14 +1159,12 @@ enum dl_dev_state { 
 * @suppliers: List of links to supplier devices.

 * @consumers: List of links to consumer devices.

 * @needs_suppliers: Hook to global list of devices waiting for suppliers.

 * @defer_sync: Hook to global list of devices that have deferred sync_state.

 * @status: Driver status information.

 */

struct dev_links_info {

	struct list_head suppliers;

	struct list_head consumers;

	struct list_head needs_suppliers;

	struct list_head defer_sync;

	enum dl_dev_state status;

};
@@ -1262,9 +1242,6 @@ struct dev_links_info { 
 *              device.

 * @has_edit_links: This device has a driver than is capable of

 *		    editing the device links created by driver core.

 * @state_synced: The hardware state of this device has been synced to match

 *		  the software state of this device by calling the driver/bus

 *		  sync_state() callback.

 * @dma_coherent: this particular device is dma coherent, even if the

 *		architecture supports non-coherent devices.

 *
@@ -1362,7 +1339,6 @@ struct device { 
	bool			offline:1;

	bool			of_node_reused:1;

	bool			has_edit_links:1;

	bool			state_synced:1;

#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \

    defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \

    defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
@@ -1707,8 +1683,6 @@ struct device_link *device_link_add(struct device *consumer, 
void device_link_del(struct device_link *link);

void device_link_remove(void *consumer, struct device *supplier);

void device_link_remove_from_wfs(struct device *consumer);

void device_links_supplier_sync_state_pause(void);

void device_links_supplier_sync_state_resume(void);



#ifndef dev_fmt

#define dev_fmt(fmt) fmt

CRA Git | Maintained and supported by SUSTech CRA and CCSE