kernel-ark/drivers/pnp/core.c
Bjorn Helgaas b173491339 PNP: remove null pointer checks
Remove some null pointer checks.  Null pointers in these areas indicate
programming errors, and I think it's better to oops immediately rather
than return an error that is easily ignored.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Acked-by: Adam Belay <abelay@novell.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2007-08-24 01:27:24 -04:00

165 lines
3.6 KiB
C

/*
* core.c - contains all core device and protocol registration functions
*
* Copyright 2002 Adam Belay <ambx1@neo.rr.com>
*/
#include <linux/pnp.h>
#include <linux/types.h>
#include <linux/list.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/dma-mapping.h>
#include "base.h"
static LIST_HEAD(pnp_protocols);
LIST_HEAD(pnp_global);
DEFINE_SPINLOCK(pnp_lock);
/*
* ACPI or PNPBIOS should tell us about all platform devices, so we can
* skip some blind probes. ISAPNP typically enumerates only plug-in ISA
* devices, not built-in things like COM ports.
*/
int pnp_platform_devices;
EXPORT_SYMBOL(pnp_platform_devices);
void *pnp_alloc(long size)
{
void *result;
result = kzalloc(size, GFP_KERNEL);
if (!result) {
printk(KERN_ERR "pnp: Out of Memory\n");
return NULL;
}
return result;
}
/**
* pnp_protocol_register - adds a pnp protocol to the pnp layer
* @protocol: pointer to the corresponding pnp_protocol structure
*
* Ex protocols: ISAPNP, PNPBIOS, etc
*/
int pnp_register_protocol(struct pnp_protocol *protocol)
{
int nodenum;
struct list_head *pos;
INIT_LIST_HEAD(&protocol->devices);
INIT_LIST_HEAD(&protocol->cards);
nodenum = 0;
spin_lock(&pnp_lock);
/* assign the lowest unused number */
list_for_each(pos, &pnp_protocols) {
struct pnp_protocol *cur = to_pnp_protocol(pos);
if (cur->number == nodenum) {
pos = &pnp_protocols;
nodenum++;
}
}
list_add_tail(&protocol->protocol_list, &pnp_protocols);
spin_unlock(&pnp_lock);
protocol->number = nodenum;
sprintf(protocol->dev.bus_id, "pnp%d", nodenum);
return device_register(&protocol->dev);
}
/**
* pnp_protocol_unregister - removes a pnp protocol from the pnp layer
* @protocol: pointer to the corresponding pnp_protocol structure
*/
void pnp_unregister_protocol(struct pnp_protocol *protocol)
{
spin_lock(&pnp_lock);
list_del(&protocol->protocol_list);
spin_unlock(&pnp_lock);
device_unregister(&protocol->dev);
}
static void pnp_free_ids(struct pnp_dev *dev)
{
struct pnp_id *id;
struct pnp_id *next;
id = dev->id;
while (id) {
next = id->next;
kfree(id);
id = next;
}
}
static void pnp_release_device(struct device *dmdev)
{
struct pnp_dev *dev = to_pnp_dev(dmdev);
pnp_free_option(dev->independent);
pnp_free_option(dev->dependent);
pnp_free_ids(dev);
kfree(dev);
}
int __pnp_add_device(struct pnp_dev *dev)
{
int ret;
pnp_fixup_device(dev);
dev->dev.bus = &pnp_bus_type;
dev->dev.dma_mask = &dev->dma_mask;
dev->dma_mask = dev->dev.coherent_dma_mask = DMA_24BIT_MASK;
dev->dev.release = &pnp_release_device;
dev->status = PNP_READY;
spin_lock(&pnp_lock);
list_add_tail(&dev->global_list, &pnp_global);
list_add_tail(&dev->protocol_list, &dev->protocol->devices);
spin_unlock(&pnp_lock);
ret = device_register(&dev->dev);
if (ret == 0)
pnp_interface_attach_device(dev);
return ret;
}
/*
* pnp_add_device - adds a pnp device to the pnp layer
* @dev: pointer to dev to add
*
* adds to driver model, name database, fixups, interface, etc.
*/
int pnp_add_device(struct pnp_dev *dev)
{
if (dev->card)
return -EINVAL;
dev->dev.parent = &dev->protocol->dev;
sprintf(dev->dev.bus_id, "%02x:%02x", dev->protocol->number,
dev->number);
return __pnp_add_device(dev);
}
void __pnp_remove_device(struct pnp_dev *dev)
{
spin_lock(&pnp_lock);
list_del(&dev->global_list);
list_del(&dev->protocol_list);
spin_unlock(&pnp_lock);
device_unregister(&dev->dev);
}
static int __init pnp_init(void)
{
printk(KERN_INFO "Linux Plug and Play Support v0.97 (c) Adam Belay\n");
return bus_register(&pnp_bus_type);
}
subsys_initcall(pnp_init);