mirror of
				git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
				synced 2025-09-04 20:19:47 +08:00 
			
		
		
		
	 32a5a0c047
			
		
	
	
		32a5a0c047
		
	
	
	
	
		
			
			The isa_bus_init function must be called before drivers which utilize
the ISA bus driver are registered. A race condition for initilization
exists if device_initcall is used (the isa_bus_init callback is placed
in the same initcall level as dependent drivers which use module_init).
This patch ensures that isa_bus_init is called first by utilizing
postcore_initcall in favor of device_initcall.
Fixes: a5117ba7da ("[PATCH] Driver model: add ISA bus")
Cc: Rene Herman <rene.herman@keyaccess.nl>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
		
	
			
		
			
				
	
	
		
			184 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			184 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * ISA bus.
 | |
|  */
 | |
| 
 | |
| #include <linux/device.h>
 | |
| #include <linux/kernel.h>
 | |
| #include <linux/slab.h>
 | |
| #include <linux/module.h>
 | |
| #include <linux/init.h>
 | |
| #include <linux/dma-mapping.h>
 | |
| #include <linux/isa.h>
 | |
| 
 | |
| static struct device isa_bus = {
 | |
| 	.init_name	= "isa"
 | |
| };
 | |
| 
 | |
| struct isa_dev {
 | |
| 	struct device dev;
 | |
| 	struct device *next;
 | |
| 	unsigned int id;
 | |
| };
 | |
| 
 | |
| #define to_isa_dev(x) container_of((x), struct isa_dev, dev)
 | |
| 
 | |
| static int isa_bus_match(struct device *dev, struct device_driver *driver)
 | |
| {
 | |
| 	struct isa_driver *isa_driver = to_isa_driver(driver);
 | |
| 
 | |
| 	if (dev->platform_data == isa_driver) {
 | |
| 		if (!isa_driver->match ||
 | |
| 			isa_driver->match(dev, to_isa_dev(dev)->id))
 | |
| 			return 1;
 | |
| 		dev->platform_data = NULL;
 | |
| 	}
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int isa_bus_probe(struct device *dev)
 | |
| {
 | |
| 	struct isa_driver *isa_driver = dev->platform_data;
 | |
| 
 | |
| 	if (isa_driver->probe)
 | |
| 		return isa_driver->probe(dev, to_isa_dev(dev)->id);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int isa_bus_remove(struct device *dev)
 | |
| {
 | |
| 	struct isa_driver *isa_driver = dev->platform_data;
 | |
| 
 | |
| 	if (isa_driver->remove)
 | |
| 		return isa_driver->remove(dev, to_isa_dev(dev)->id);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static void isa_bus_shutdown(struct device *dev)
 | |
| {
 | |
| 	struct isa_driver *isa_driver = dev->platform_data;
 | |
| 
 | |
| 	if (isa_driver->shutdown)
 | |
| 		isa_driver->shutdown(dev, to_isa_dev(dev)->id);
 | |
| }
 | |
| 
 | |
| static int isa_bus_suspend(struct device *dev, pm_message_t state)
 | |
| {
 | |
| 	struct isa_driver *isa_driver = dev->platform_data;
 | |
| 
 | |
| 	if (isa_driver->suspend)
 | |
| 		return isa_driver->suspend(dev, to_isa_dev(dev)->id, state);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int isa_bus_resume(struct device *dev)
 | |
| {
 | |
| 	struct isa_driver *isa_driver = dev->platform_data;
 | |
| 
 | |
| 	if (isa_driver->resume)
 | |
| 		return isa_driver->resume(dev, to_isa_dev(dev)->id);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static struct bus_type isa_bus_type = {
 | |
| 	.name		= "isa",
 | |
| 	.match		= isa_bus_match,
 | |
| 	.probe		= isa_bus_probe,
 | |
| 	.remove		= isa_bus_remove,
 | |
| 	.shutdown	= isa_bus_shutdown,
 | |
| 	.suspend	= isa_bus_suspend,
 | |
| 	.resume		= isa_bus_resume
 | |
| };
 | |
| 
 | |
| static void isa_dev_release(struct device *dev)
 | |
| {
 | |
| 	kfree(to_isa_dev(dev));
 | |
| }
 | |
| 
 | |
| void isa_unregister_driver(struct isa_driver *isa_driver)
 | |
| {
 | |
| 	struct device *dev = isa_driver->devices;
 | |
| 
 | |
| 	while (dev) {
 | |
| 		struct device *tmp = to_isa_dev(dev)->next;
 | |
| 		device_unregister(dev);
 | |
| 		dev = tmp;
 | |
| 	}
 | |
| 	driver_unregister(&isa_driver->driver);
 | |
| }
 | |
| EXPORT_SYMBOL_GPL(isa_unregister_driver);
 | |
| 
 | |
| int isa_register_driver(struct isa_driver *isa_driver, unsigned int ndev)
 | |
| {
 | |
| 	int error;
 | |
| 	unsigned int id;
 | |
| 
 | |
| 	isa_driver->driver.bus	= &isa_bus_type;
 | |
| 	isa_driver->devices	= NULL;
 | |
| 
 | |
| 	error = driver_register(&isa_driver->driver);
 | |
| 	if (error)
 | |
| 		return error;
 | |
| 
 | |
| 	for (id = 0; id < ndev; id++) {
 | |
| 		struct isa_dev *isa_dev;
 | |
| 
 | |
| 		isa_dev = kzalloc(sizeof *isa_dev, GFP_KERNEL);
 | |
| 		if (!isa_dev) {
 | |
| 			error = -ENOMEM;
 | |
| 			break;
 | |
| 		}
 | |
| 
 | |
| 		isa_dev->dev.parent	= &isa_bus;
 | |
| 		isa_dev->dev.bus	= &isa_bus_type;
 | |
| 
 | |
| 		dev_set_name(&isa_dev->dev, "%s.%u",
 | |
| 			     isa_driver->driver.name, id);
 | |
| 		isa_dev->dev.platform_data	= isa_driver;
 | |
| 		isa_dev->dev.release		= isa_dev_release;
 | |
| 		isa_dev->id			= id;
 | |
| 
 | |
| 		isa_dev->dev.coherent_dma_mask = DMA_BIT_MASK(24);
 | |
| 		isa_dev->dev.dma_mask = &isa_dev->dev.coherent_dma_mask;
 | |
| 
 | |
| 		error = device_register(&isa_dev->dev);
 | |
| 		if (error) {
 | |
| 			put_device(&isa_dev->dev);
 | |
| 			break;
 | |
| 		}
 | |
| 
 | |
| 		if (isa_dev->dev.platform_data) {
 | |
| 			isa_dev->next = isa_driver->devices;
 | |
| 			isa_driver->devices = &isa_dev->dev;
 | |
| 		} else
 | |
| 			device_unregister(&isa_dev->dev);
 | |
| 	}
 | |
| 
 | |
| 	if (!error && !isa_driver->devices)
 | |
| 		error = -ENODEV;
 | |
| 
 | |
| 	if (error)
 | |
| 		isa_unregister_driver(isa_driver);
 | |
| 
 | |
| 	return error;
 | |
| }
 | |
| EXPORT_SYMBOL_GPL(isa_register_driver);
 | |
| 
 | |
| static int __init isa_bus_init(void)
 | |
| {
 | |
| 	int error;
 | |
| 
 | |
| 	error = bus_register(&isa_bus_type);
 | |
| 	if (!error) {
 | |
| 		error = device_register(&isa_bus);
 | |
| 		if (error)
 | |
| 			bus_unregister(&isa_bus_type);
 | |
| 	}
 | |
| 	return error;
 | |
| }
 | |
| 
 | |
| postcore_initcall(isa_bus_init);
 |