[PATCH] Driver core: add platform_create_bundle() helper

[PATCH] Driver core: add platform_create_bundle() helper

[Dmitry Torokhov]

Many legacy-style module create singleton platform devices themselves,
along with corresponding platform driver. Instead of replicating error
handling code in all such drivers, provide a helper that allocates and
registers a single platform device and a driver and binds them together.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
---

Greg,

Please consider applying this patch, preferably to your 2.6.33 queue so
that I can start working on converting the users - there are a few of
them creating both the device and the driver and handling errors with
various degrees of success.

Thanks!


 drivers/base/platform.c         |   58 +++++++++++++++++++++++++++++++++++++++
 include/linux/platform_device.h |    5 +++
 2 files changed, 63 insertions(+), 0 deletions(-)


diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 58efaf2..937d580 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -548,6 +548,64 @@ int __init_or_module platform_driver_probe(struct platform_driver *drv,
 }
 EXPORT_SYMBOL_GPL(platform_driver_probe);
 
+/**
+ * platform_create_bundle - register driver and create corresponding device
+ * @driver: platform driver structure
+ * @probe: the driver probe routine, probably from an __init section
+ * @res: set of resources that needs to be allocated for the device
+ * @n_res: number of resources
+ * @data: platform specific data for this platform device
+ * @size: size of platform specific data
+ *
+ * Use this in legacy-style modules that probe hardware directly and
+ * register a single platform device and corresponding platform driver.
+ */
+struct platform_device * __init_or_module platform_create_bundle(
+			struct platform_driver *driver,
+			int (*probe)(struct platform_device *),
+			struct resource *res, unsigned int n_res,
+			const void *data, size_t size)
+{
+	struct platform_device *pdev;
+	int error;
+
+	pdev = platform_device_alloc(driver->driver.name, -1);
+	if (!pdev) {
+		error = -ENOMEM;
+		goto err_out;
+	}
+
+	if (res) {
+		error = platform_device_add_resources(pdev, res, n_res);
+		if (error)
+			goto err_pdev_put;
+	}
+
+	if (data) {
+		error = platform_device_add_data(pdev, data, size);
+		if (error)
+			goto err_pdev_put;
+	}
+
+	error = platform_device_add(pdev);
+	if (error)
+		goto err_pdev_put;
+
+	error = platform_driver_probe(driver, probe);
+	if (error)
+		goto err_pdev_del;
+
+	return pdev;
+
+err_pdev_del:
+	platform_device_del(pdev);
+err_pdev_put:
+	platform_device_put(pdev);
+err_out:
+	return ERR_PTR(error);
+}
+EXPORT_SYMBOL_GPL(platform_create_bundle);
+
 /* modalias support enables more hands-off userspace setup:
  * (a) environment variable lets new-style hotplug events work once system is
  *     fully running:  "modprobe $MODALIAS"
diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h
index 71ff887..25e64b4 100644
--- a/include/linux/platform_device.h
+++ b/include/linux/platform_device.h
@@ -77,6 +77,11 @@ extern int platform_driver_probe(struct platform_driver *driver,
 #define platform_get_drvdata(_dev)	dev_get_drvdata(&(_dev)->dev)
 #define platform_set_drvdata(_dev,data)	dev_set_drvdata(&(_dev)->dev, (data))
 
+extern struct platform_device *platform_create_bundle(struct platform_driver *driver,
+					int (*probe)(struct platform_device *),
+					struct resource *res, unsigned int n_res,
+					const void *data, size_t size);
+
 /* early platform driver interface */
 struct early_platform_driver {
 	const char *class_str;
-- 
Dmitry