[PATCH v2 1/2] siox: Use bus_type functions for probe, remote and shutdown

[Uwe Kleine-König]

The eventual goal is to get rid of the callbacks in struct
device_driver.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
---
 drivers/siox/siox-core.c | 49 ++++++++++++++++++++--------------------
 1 file changed, 25 insertions(+), 24 deletions(-)

diff --git a/drivers/siox/siox-core.c b/drivers/siox/siox-core.c
index f8c08fb9891d..b56cdcb52967 100644
--- a/drivers/siox/siox-core.c
+++ b/drivers/siox/siox-core.c
@@ -512,41 +512,48 @@ static int siox_match(struct device *dev, struct device_driver *drv)
 	return 1;
 }
 
-static struct bus_type siox_bus_type = {
-	.name = "siox",
-	.match = siox_match,
-};
-
-static int siox_driver_probe(struct device *dev)
+static int siox_probe(struct device *dev)
 {
 	struct siox_driver *sdriver = to_siox_driver(dev->driver);
 	struct siox_device *sdevice = to_siox_device(dev);
-	int ret;
 
-	ret = sdriver->probe(sdevice);
-	return ret;
+	return sdriver->probe(sdevice);
 }
 
-static int siox_driver_remove(struct device *dev)
+static int siox_remove(struct device *dev)
 {
 	struct siox_driver *sdriver =
 		container_of(dev->driver, struct siox_driver, driver);
 	struct siox_device *sdevice = to_siox_device(dev);
-	int ret;
+	int ret = 0;
+
+	if (sdriver->remove)
+		ret = sdriver->remove(sdevice);
 
-	ret = sdriver->remove(sdevice);
 	return ret;
 }
 
-static void siox_driver_shutdown(struct device *dev)
+static void siox_shutdown(struct device *dev)
 {
-	struct siox_driver *sdriver =
-		container_of(dev->driver, struct siox_driver, driver);
 	struct siox_device *sdevice = to_siox_device(dev);
+	struct siox_driver *sdriver;
 
-	sdriver->shutdown(sdevice);
+	if (!dev->driver)
+		return;
+
+	sdriver = container_of(dev->driver, struct siox_driver, driver);
+	if (sdriver->shutdown)
+		sdriver->shutdown(sdevice);
 }
 
+static struct bus_type siox_bus_type = {
+	.name = "siox",
+	.match = siox_match,
+	.probe = siox_probe,
+	.remove = siox_remove,
+	.shutdown = siox_shutdown,
+};
+
 static ssize_t active_show(struct device *dev,
 			   struct device_attribute *attr, char *buf)
 {
@@ -882,7 +889,8 @@ int __siox_driver_register(struct siox_driver *sdriver, struct module *owner)
 	if (unlikely(!siox_is_registered))
 		return -EPROBE_DEFER;
 
-	if (!sdriver->set_data && !sdriver->get_data) {
+	if (!sdriver->probe ||
+	    (!sdriver->set_data && !sdriver->get_data)) {
 		pr_err("Driver %s doesn't provide needed callbacks\n",
 		       sdriver->driver.name);
 		return -EINVAL;
@@ -891,13 +899,6 @@ int __siox_driver_register(struct siox_driver *sdriver, struct module *owner)
 	sdriver->driver.owner = owner;
 	sdriver->driver.bus = &siox_bus_type;
 
-	if (sdriver->probe)
-		sdriver->driver.probe = siox_driver_probe;
-	if (sdriver->remove)
-		sdriver->driver.remove = siox_driver_remove;
-	if (sdriver->shutdown)
-		sdriver->driver.shutdown = siox_driver_shutdown;
-
 	ret = driver_register(&sdriver->driver);
 	if (ret)
 		pr_err("Failed to register siox driver %s (%d)\n",
-- 
2.29.2