[PATCH] i2c: i2c-dev: Create 'name' attribute automatically

Guenter Roeck
2013-08-31T16:30:32Z

The 'name' attribute is needed for all i2c-dev class devices, meaning
it can be created automatically by pointing to it in the class data
structure. This simplifies the code and reduces the probability for race
conditions.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
drivers/i2c/i2c-dev.c | 32 ++++++++++++++++----------------
1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index c3ccdea..46eea02 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -111,7 +111,11 @@ static ssize_t show_adapter_name(struct device *dev,
return -ENODEV;
return sprintf(buf, "%s\n", i2c_dev->adap->name);
}
-static DEVICE_ATTR(name, S_IRUGO, show_adapter_name, NULL);
+
+static struct device_attribute i2c_dev_attributes[] = {
+ __ATTR(name, S_IRUGO, show_adapter_name, NULL),
+ { }
+};

/* ------------------------------------------------------------------------- */

@@ -538,7 +542,11 @@ static const struct file_operations i2cdev_fops = {

/* ------------------------------------------------------------------------- */

-static struct class *i2c_dev_class;
+static struct class i2c_dev_class = {
+ .owner = THIS_MODULE,
+ .name = "i2c-dev",
+ .dev_attrs = i2c_dev_attributes,
+};

static int i2cdev_attach_adapter(struct device *dev, void *dummy)
{
@@ -555,22 +563,17 @@ static int i2cdev_attach_adapter(struct device *dev, void *dummy)
return PTR_ERR(i2c_dev);

/* register this i2c device with the driver core */
- i2c_dev->dev = device_create(i2c_dev_class, &adap->dev,
+ i2c_dev->dev = device_create(&i2c_dev_class, &adap->dev,
MKDEV(I2C_MAJOR, adap->nr), NULL,
"i2c-%d", adap->nr);
if (IS_ERR(i2c_dev->dev)) {
res = PTR_ERR(i2c_dev->dev);
goto error;
}
- res = device_create_file(i2c_dev->dev, &dev_attr_name);
- if (res)
- goto error_destroy;

pr_debug("i2c-dev: adapter [%s] registered as minor %d\n",
adap->name, adap->nr);
return 0;
-error_destroy:
- device_destroy(i2c_dev_class, MKDEV(I2C_MAJOR, adap->nr));
error:
return_i2c_dev(i2c_dev);
return res;
@@ -589,9 +592,8 @@ static int i2cdev_detach_adapter(struct device *dev, void *dummy)
if (!i2c_dev) /* attach_adapter must have failed */
return 0;

- device_remove_file(i2c_dev->dev, &dev_attr_name);
return_i2c_dev(i2c_dev);
- device_destroy(i2c_dev_class, MKDEV(I2C_MAJOR, adap->nr));
+ device_destroy(&i2c_dev_class, MKDEV(I2C_MAJOR, adap->nr));

pr_debug("i2c-dev: adapter [%s] unregistered\n", adap->name);
return 0;
@@ -632,11 +634,9 @@ static int __init i2c_dev_init(void)
if (res)
goto out;

- i2c_dev_class = class_create(THIS_MODULE, "i2c-dev");
- if (IS_ERR(i2c_dev_class)) {
- res = PTR_ERR(i2c_dev_class);
+ res = class_register(&i2c_dev_class);
+ if (res)
goto out_unreg_chrdev;
- }

/* Keep track of adapters which will be added or removed later */
res = bus_register_notifier(&i2c_bus_type, &i2cdev_notifier);
@@ -649,7 +649,7 @@ static int __init i2c_dev_init(void)
return 0;

out_unreg_class:
- class_destroy(i2c_dev_class);
+ class_unregister(&i2c_dev_class);
out_unreg_chrdev:
unregister_chrdev(I2C_MAJOR, "i2c");
out:
@@ -661,7 +661,7 @@ static void __exit i2c_dev_exit(void)
{
bus_unregister_notifier(&i2c_bus_type, &i2cdev_notifier);
i2c_for_each_dev(NULL, i2cdev_detach_adapter);
- class_destroy(i2c_dev_class);
+ class_unregister(&i2c_dev_class);
unregister_chrdev(I2C_MAJOR, "i2c");
}

--
1.7.9.7