#include <linux/platform_device.h>
#include <linux/mutex.h>
#include <linux/completion.h>
+#include <linux/hardirq.h>
+#include <linux/irqflags.h>
#include <asm/uaccess.h>
#include <asm/semaphore.h>
#include "i2c-core.h"
-static LIST_HEAD(drivers);
-static DEFINE_MUTEX(core_lists);
+static DEFINE_MUTEX(core_lock);
static DEFINE_IDR(i2c_adapter_idr);
#define is_newstyle_driver(d) ((d)->probe || (d)->remove)
mutex_unlock(&__i2c_board_lock);
}
+static int i2c_do_add_adapter(struct device_driver *d, void *data)
+{
+ struct i2c_driver *driver = to_i2c_driver(d);
+ struct i2c_adapter *adap = data;
+
+ if (driver->attach_adapter) {
+ /* We ignore the return code; if it fails, too bad */
+ driver->attach_adapter(adap);
+ }
+ return 0;
+}
+
static int i2c_register_adapter(struct i2c_adapter *adap)
{
- int res = 0;
- struct list_head *item;
- struct i2c_driver *driver;
+ int res = 0, dummy;
mutex_init(&adap->bus_lock);
mutex_init(&adap->clist_lock);
INIT_LIST_HEAD(&adap->clients);
- mutex_lock(&core_lists);
+ mutex_lock(&core_lock);
/* Add the adapter to the driver core.
* If the parent pointer is not set up,
i2c_scan_static_board_info(adap);
/* let legacy drivers scan this bus for matching devices */
- list_for_each(item,&drivers) {
- driver = list_entry(item, struct i2c_driver, list);
- if (driver->attach_adapter)
- /* We ignore the return code; if it fails, too bad */
- driver->attach_adapter(adap);
- }
+ dummy = bus_for_each_drv(&i2c_bus_type, NULL, adap,
+ i2c_do_add_adapter);
out_unlock:
- mutex_unlock(&core_lists);
+ mutex_unlock(&core_lock);
return res;
out_list:
if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0)
return -ENOMEM;
- mutex_lock(&core_lists);
+ mutex_lock(&core_lock);
/* "above" here means "above or equal to", sigh */
res = idr_get_new_above(&i2c_adapter_idr, adapter,
__i2c_first_dynamic_bus_num, &id);
- mutex_unlock(&core_lists);
+ mutex_unlock(&core_lock);
if (res < 0) {
if (res == -EAGAIN)
if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0)
return -ENOMEM;
- mutex_lock(&core_lists);
+ mutex_lock(&core_lock);
/* "above" here means "above or equal to", sigh;
* we need the "equal to" result to force the result
*/
status = -EBUSY;
idr_remove(&i2c_adapter_idr, id);
}
- mutex_unlock(&core_lists);
+ mutex_unlock(&core_lock);
if (status == -EAGAIN)
goto retry;
}
EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter);
+static int i2c_do_del_adapter(struct device_driver *d, void *data)
+{
+ struct i2c_driver *driver = to_i2c_driver(d);
+ struct i2c_adapter *adapter = data;
+ int res;
+
+ if (!driver->detach_adapter)
+ return 0;
+ res = driver->detach_adapter(adapter);
+ if (res)
+ dev_err(&adapter->dev, "detach_adapter failed (%d) "
+ "for driver [%s]\n", res, driver->driver.name);
+ return res;
+}
+
/**
* i2c_del_adapter - unregister I2C adapter
* @adap: the adapter being unregistered
int i2c_del_adapter(struct i2c_adapter *adap)
{
struct list_head *item, *_n;
- struct i2c_driver *driver;
struct i2c_client *client;
int res = 0;
- mutex_lock(&core_lists);
+ mutex_lock(&core_lock);
/* First make sure that this adapter was ever added */
if (idr_find(&i2c_adapter_idr, adap->nr) != adap) {
goto out_unlock;
}
- list_for_each(item,&drivers) {
- driver = list_entry(item, struct i2c_driver, list);
- if (driver->detach_adapter)
- if ((res = driver->detach_adapter(adap))) {
- dev_err(&adap->dev, "detach_adapter failed "
- "for driver [%s]\n",
- driver->driver.name);
- goto out_unlock;
- }
- }
+ /* Tell drivers about this removal */
+ res = bus_for_each_drv(&i2c_bus_type, NULL, adap,
+ i2c_do_del_adapter);
+ if (res)
+ goto out_unlock;
/* detach any active clients. This must be done first, because
* it can fail; in which case we give up. */
dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name);
out_unlock:
- mutex_unlock(&core_lists);
+ mutex_unlock(&core_lock);
return res;
}
EXPORT_SYMBOL(i2c_del_adapter);
if (res)
return res;
- mutex_lock(&core_lists);
+ mutex_lock(&core_lock);
- list_add_tail(&driver->list,&drivers);
pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name);
/* legacy drivers scan i2c busses directly */
up(&i2c_adapter_class.sem);
}
- mutex_unlock(&core_lists);
+ mutex_unlock(&core_lock);
return 0;
}
EXPORT_SYMBOL(i2c_register_driver);
struct i2c_client *client;
struct i2c_adapter *adap;
- mutex_lock(&core_lists);
+ mutex_lock(&core_lock);
/* new-style driver? */
if (is_newstyle_driver(driver))
unregister:
driver_unregister(&driver->driver);
- list_del(&driver->list);
pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name);
- mutex_unlock(&core_lists);
+ mutex_unlock(&core_lock);
}
EXPORT_SYMBOL(i2c_del_driver);
}
#endif
- mutex_lock_nested(&adap->bus_lock, adap->level);
+ if (in_atomic() || irqs_disabled()) {
+ ret = mutex_trylock(&adap->bus_lock);
+ if (!ret)
+ /* I2C activity is ongoing. */
+ return -EAGAIN;
+ } else {
+ mutex_lock_nested(&adap->bus_lock, adap->level);
+ }
+
ret = adap->algo->master_xfer(adap,msgs,num);
mutex_unlock(&adap->bus_lock);
{
struct i2c_adapter *adapter;
- mutex_lock(&core_lists);
+ mutex_lock(&core_lock);
adapter = (struct i2c_adapter *)idr_find(&i2c_adapter_idr, id);
if (adapter && !try_module_get(adapter->owner))
adapter = NULL;
- mutex_unlock(&core_lists);
+ mutex_unlock(&core_lock);
return adapter;
}
EXPORT_SYMBOL(i2c_get_adapter);
git.openpandora.org / pandora-kernel.git / blobdiff