powerpc/macio: Add devres support to macio_device

This adds some basic devres support. When enabled via macio_enable_devres()
resources requested by drivers will be automatically released.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Benjamin Herrenschmidt 2009-12-01 14:36:26 +00:00
parent e15a113700
commit 7fb19ea054
2 changed files with 49 additions and 0 deletions

View File

@ -78,6 +78,8 @@ static inline unsigned long macio_resource_len(struct macio_dev *dev, int resour
return res->end - res->start + 1;
}
extern int macio_enable_devres(struct macio_dev *dev);
extern int macio_request_resource(struct macio_dev *dev, int resource_no, const char *name);
extern void macio_release_resource(struct macio_dev *dev, int resource_no);
extern int macio_request_resources(struct macio_dev *dev, const char *name);

View File

@ -538,6 +538,42 @@ void macio_unregister_driver(struct macio_driver *drv)
driver_unregister(&drv->driver);
}
/* Managed MacIO resources */
struct macio_devres {
u32 res_mask;
};
static void maciom_release(struct device *gendev, void *res)
{
struct macio_dev *dev = to_macio_device(gendev);
struct macio_devres *dr = res;
int i, max;
max = min(dev->n_resources, 32);
for (i = 0; i < max; i++) {
if (dr->res_mask & (1 << i))
macio_release_resource(dev, i);
}
}
int macio_enable_devres(struct macio_dev *dev)
{
struct macio_devres *dr;
dr = devres_find(&dev->ofdev.dev, maciom_release, NULL, NULL);
if (!dr) {
dr = devres_alloc(maciom_release, sizeof(*dr), GFP_KERNEL);
if (!dr)
return -ENOMEM;
}
return devres_get(&dev->ofdev.dev, dr, NULL, NULL) != NULL;
}
static struct macio_devres * find_macio_dr(struct macio_dev *dev)
{
return devres_find(&dev->ofdev.dev, maciom_release, NULL, NULL);
}
/**
* macio_request_resource - Request an MMIO resource
* @dev: pointer to the device holding the resource
@ -555,6 +591,8 @@ void macio_unregister_driver(struct macio_driver *drv)
int macio_request_resource(struct macio_dev *dev, int resource_no,
const char *name)
{
struct macio_devres *dr = find_macio_dr(dev);
if (macio_resource_len(dev, resource_no) == 0)
return 0;
@ -562,6 +600,9 @@ int macio_request_resource(struct macio_dev *dev, int resource_no,
macio_resource_len(dev, resource_no),
name))
goto err_out;
if (dr && resource_no < 32)
dr->res_mask |= 1 << resource_no;
return 0;
@ -582,10 +623,14 @@ int macio_request_resource(struct macio_dev *dev, int resource_no,
*/
void macio_release_resource(struct macio_dev *dev, int resource_no)
{
struct macio_devres *dr = find_macio_dr(dev);
if (macio_resource_len(dev, resource_no) == 0)
return;
release_mem_region(macio_resource_start(dev, resource_no),
macio_resource_len(dev, resource_no));
if (dr && resource_no < 32)
dr->res_mask &= ~(1 << resource_no);
}
/**
@ -744,3 +789,5 @@ EXPORT_SYMBOL(macio_request_resource);
EXPORT_SYMBOL(macio_release_resource);
EXPORT_SYMBOL(macio_request_resources);
EXPORT_SYMBOL(macio_release_resources);
EXPORT_SYMBOL(macio_enable_devres);