[PATCH] dcdbas: convert to the new platform device interface

Do not use platform_device_register_simple() as it is going away, define
dcdbas_driver and implement ->probe() and ->remove() functions so manual
binding and unbinding will work with this driver.

Also switch to using attribute_group when creating sysfs attributes and
make sure to check and handle errors; explicitely remove attributes when
detaching driver.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 88 insertions, 22 deletions

diff --git a/drivers/firmware/dcdbas.c b/drivers/firmware/dcdbas.c
index 4652512f7d1a..3a4e5c5b4e1f 100644
--- a/drivers/firmware/dcdbas.c
+++ b/drivers/firmware/dcdbas.c
@@ -530,30 +530,27 @@ static DCDBAS_DEV_ATTR_RW(host_control_action);
 static DCDBAS_DEV_ATTR_RW(host_control_smi_type);
 static DCDBAS_DEV_ATTR_RW(host_control_on_shutdown);
 
-static struct device_attribute *dcdbas_dev_attrs[] = {
-        &dev_attr_smi_data_buf_size,
-        &dev_attr_smi_data_buf_phys_addr,
-        &dev_attr_smi_request,
-        &dev_attr_host_control_action,
-        &dev_attr_host_control_smi_type,
-        &dev_attr_host_control_on_shutdown,
+static struct attribute *dcdbas_dev_attrs[] = {
+        &dev_attr_smi_data_buf_size.attr,
+        &dev_attr_smi_data_buf_phys_addr.attr,
+        &dev_attr_smi_request.attr,
+        &dev_attr_host_control_action.attr,
+        &dev_attr_host_control_smi_type.attr,
+        &dev_attr_host_control_on_shutdown.attr,
         NULL
 };
 
-/**
- * dcdbas_init: initialize driver
- */
-static int __init dcdbas_init(void)
+static struct attribute_group dcdbas_attr_group = {
+        .attrs = dcdbas_dev_attrs,
+};
+
+static int __devinit dcdbas_probe(struct platform_device *dev)
 {
-        int i;
+        int i, error;
 
         host_control_action = HC_ACTION_NONE;
         host_control_smi_type = HC_SMITYPE_NONE;
 
-        dcdbas_pdev = platform_device_register_simple(DRIVER_NAME, -1, NULL, 0);
-        if (IS_ERR(dcdbas_pdev))
-                return PTR_ERR(dcdbas_pdev);
-
         /*
          * BIOS SMI calls require buffer addresses be in 32-bit address space.
          * This is done by setting the DMA mask below.
@@ -561,19 +558,79 @@ static int __init dcdbas_init(void)
         dcdbas_pdev->dev.coherent_dma_mask = DMA_32BIT_MASK;
         dcdbas_pdev->dev.dma_mask = &dcdbas_pdev->dev.coherent_dma_mask;
 
+        error = sysfs_create_group(&dev->dev.kobj, &dcdbas_attr_group);
+        if (error)
+                return error;
+
+        for (i = 0; dcdbas_bin_attrs[i]; i++) {
+                error = sysfs_create_bin_file(&dev->dev.kobj,
+                                              dcdbas_bin_attrs[i]);
+                if (error) {
+                        while (--i >= 0)
+                                sysfs_remove_bin_file(&dev->dev.kobj,
+                                                      dcdbas_bin_attrs[i]);
+                        sysfs_create_group(&dev->dev.kobj, &dcdbas_attr_group);
+                        return error;
+                }
+        }
+
         register_reboot_notifier(&dcdbas_reboot_nb);
 
+        dev_info(&dev->dev, "%s (version %s)\n",
+                 DRIVER_DESCRIPTION, DRIVER_VERSION);
+
+        return 0;
+}
+
+static int __devexit dcdbas_remove(struct platform_device *dev)
+{
+        int i;
+
+        unregister_reboot_notifier(&dcdbas_reboot_nb);
         for (i = 0; dcdbas_bin_attrs[i]; i++)
-                sysfs_create_bin_file(&dcdbas_pdev->dev.kobj,
-                                      dcdbas_bin_attrs[i]);
+                sysfs_remove_bin_file(&dev->dev.kobj, dcdbas_bin_attrs[i]);
+        sysfs_remove_group(&dev->dev.kobj, &dcdbas_attr_group);
 
-        for (i = 0; dcdbas_dev_attrs[i]; i++)
-                device_create_file(&dcdbas_pdev->dev, dcdbas_dev_attrs[i]);
+        return 0;
+}
 
-        dev_info(&dcdbas_pdev->dev, "%s (version %s)\n",
-                 DRIVER_DESCRIPTION, DRIVER_VERSION);
+static struct platform_driver dcdbas_driver = {
+        .driver         = {
+                .name   = DRIVER_NAME,
+                .owner  = THIS_MODULE,
+        },
+        .probe          = dcdbas_probe,
+        .remove         = __devexit_p(dcdbas_remove),
+};
+
+/**
+ * dcdbas_init: initialize driver
+ */
+static int __init dcdbas_init(void)
+{
+        int error;
+
+        error = platform_driver_register(&dcdbas_driver);
+        if (error)
+                return error;
+
+        dcdbas_pdev = platform_device_alloc(DRIVER_NAME, -1);
+        if (!dcdbas_pdev) {
+                error = -ENOMEM;
+                goto err_unregister_driver;
+        }
+
+        error = platform_device_add(dcdbas_pdev);
+        if (error)
+                goto err_free_device;
 
         return 0;
+
+ err_free_device:
+        platform_device_put(dcdbas_pdev);
+ err_unregister_driver:
+        platform_driver_unregister(&dcdbas_driver);
+        return error;
 }
 
 /**
@@ -588,6 +645,15 @@ static void __exit dcdbas_exit(void)
         unregister_reboot_notifier(&dcdbas_reboot_nb);
         smi_data_buf_free();
         platform_device_unregister(dcdbas_pdev);
+        platform_driver_unregister(&dcdbas_driver);
+
+        /*
+         * We have to free the buffer here instead of dcdbas_remove
+         * because only in module exit function we can be sure that
+         * all sysfs attributes belonging to this module have been
+         * released.
+         */
+        smi_data_buf_free();
 }
 
 module_init(dcdbas_init);