This changes how the I2C core iterates devices connected to a given
i2c_adapter, making it use driver model facilities instead of the
deprecated i2c_adapter.clients list. The two functions affected are
i2c_del_adapter() and i2c_del_driver().
This is something of a bugfix: updates to that list are protected by a
lock (i2c_adapter.clist_lock) which is completly ignored by those two
iteration loops ...
Signed-off-by: David Brownell <[EMAIL PROTECTED]>
---
Builds fine, and I have a hard time seeing this break. But this
hasn't really been tested.
drivers/i2c/i2c-core.c | 91 +++++++++++++++++++++++++------------------------
1 file changed, 48 insertions(+), 43 deletions(-)
--- g26.orig/drivers/i2c/i2c-core.c 2008-05-04 20:51:58.000000000 -0700
+++ g26/drivers/i2c/i2c-core.c 2008-05-04 20:55:46.000000000 -0700
@@ -725,6 +725,44 @@ static int i2c_do_del_adapter(struct dev
return res;
}
+static int i2c_do_detach_client(struct device *dev, void *target)
+{
+ struct i2c_client *client = i2c_verify_client(dev);
+ struct i2c_driver *driver;
+ int status;
+
+ /* ignore non-i2c nodes */
+ if (!client)
+ return 0;
+
+ /* we may care only about one specific (legacy) driver */
+ driver = client->driver;
+ if (target && driver != target)
+ return 0;
+
+ /* cleanup new-style nodes */
+ if (!driver || is_newstyle_driver(driver)) {
+ i2c_unregister_device(client);
+ return 0;
+ }
+
+ /* detach legacy drivers */
+ if (driver->detach_client)
+ status = driver->detach_client(client);
+ else
+ status = -EOPNOTSUPP;
+ if (status < 0)
+ dev_err(&client->adapter->dev,
+ "detach_client failed for client "
+ "[%s] at address 0x%02x\n",
+ client->name, client->addr);
+
+ /* backwards compat: ignore failure while removing a single
+ * legacy driver; maybe we can disconnect it from other devs.
+ */
+ return target ? 0 : status;
+}
+
/**
* i2c_del_adapter - unregister I2C adapter
* @adap: the adapter being unregistered
@@ -735,8 +773,6 @@ static int i2c_do_del_adapter(struct dev
*/
int i2c_del_adapter(struct i2c_adapter *adap)
{
- struct list_head *item, *_n;
- struct i2c_client *client;
int res = 0;
mutex_lock(&core_lock);
@@ -749,34 +785,18 @@ int i2c_del_adapter(struct i2c_adapter *
goto out_unlock;
}
- /* Tell drivers about this removal */
+ /* Tell legacy drivers about this removal. They can fail...
+ * in which case, give up.
+ */
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. */
- list_for_each_safe(item, _n, &adap->clients) {
- struct i2c_driver *driver;
-
- client = list_entry(item, struct i2c_client, list);
- driver = client->driver;
-
- /* new style, follow standard driver model */
- if (!driver || is_newstyle_driver(driver)) {
- i2c_unregister_device(client);
- continue;
- }
-
- /* legacy drivers create and remove clients themselves */
- if ((res = driver->detach_client(client))) {
- dev_err(&adap->dev, "detach_client failed for client "
- "[%s] at address 0x%02x\n", client->name,
- client->addr);
- goto out_unlock;
- }
- }
+ /* Detach any active clients, both legacy and new style. */
+ res = device_for_each_child(&adap->dev, NULL, i2c_do_detach_client);
+ if (res)
+ goto out_unlock;
if (adap->has_alert_irq) {
devm_free_irq(&adap->dev, adap->irq, adap);
@@ -868,8 +888,6 @@ EXPORT_SYMBOL(i2c_register_driver);
*/
void i2c_del_driver(struct i2c_driver *driver)
{
- struct list_head *item2, *_n;
- struct i2c_client *client;
struct i2c_adapter *adap;
mutex_lock(&core_lock);
@@ -890,22 +908,9 @@ void i2c_del_driver(struct i2c_driver *d
"for driver [%s]\n",
driver->driver.name);
}
- } else {
- list_for_each_safe(item2, _n, &adap->clients) {
- client = list_entry(item2, struct i2c_client,
list);
- if (client->driver != driver)
- continue;
- dev_dbg(&adap->dev, "detaching client [%s] "
- "at 0x%02x\n", client->name,
- client->addr);
- if (driver->detach_client(client)) {
- dev_err(&adap->dev, "detach_client "
- "failed for client [%s] at "
- "0x%02x\n", client->name,
- client->addr);
- }
- }
- }
+ } else
+ device_for_each_child(&adap->dev, driver,
+ i2c_do_detach_client);
}
up(&i2c_adapter_class.sem);
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