eeepc-wmi: rework eeepc_wmi_init and eeepc_wmi_exit

The old code was using platform_driver.probe to initialize
eeepc_wmi context. That's a mistake because if probe fail,
eeepc_platform_register() won't tell anyone, and chaos will happen.

Wrap add and remove code inside eeepc_wmi_add() / eeepc_wmi_remove(),
and try to use the static platform_device only in eeepc_wmi_init()
and eeepc_wmi_exit()

The code is now very similar to eeepc-laptop, except eeepc_laptop_add
and eeepc_laptop_remove are called from acpi_driver, not module
init/exit functions, but WMI doesn't provide such functionalities (yet ?).

Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Signed-off-by: Matthew Garrett <mjg@redhat.com>

1 files changed, 79 insertions, 56 deletions

diff --git a/drivers/platform/x86/eeepc-wmi.c b/drivers/platform/x86/eeepc-wmi.c
index 0d50fbbe247..dfbb295326b 100644
--- a/drivers/platform/x86/eeepc-wmi.c
+++ b/drivers/platform/x86/eeepc-wmi.c
@@ -86,8 +86,10 @@ struct bios_args {
 struct eeepc_wmi {
         struct input_dev *inputdev;
         struct backlight_device *backlight_device;
+        struct platform_device *platform_device;
 };
 
+/* Only used in eeepc_wmi_init() and eeepc_wmi_exit() */
 static struct platform_device *platform_device;
 
 static int eeepc_wmi_input_init(struct eeepc_wmi *eeepc)
@@ -101,7 +103,7 @@ static int eeepc_wmi_input_init(struct eeepc_wmi *eeepc)
         eeepc->inputdev->name = "Eee PC WMI hotkeys";
         eeepc->inputdev->phys = EEEPC_WMI_FILE "/input0";
         eeepc->inputdev->id.bustype = BUS_HOST;
-        eeepc->inputdev->dev.parent = &platform_device->dev;
+        eeepc->inputdev->dev.parent = &eeepc->platform_device->dev;
 
         err = sparse_keymap_setup(eeepc->inputdev, eeepc_wmi_keymap, NULL);
         if (err)
@@ -234,7 +236,7 @@ static int eeepc_wmi_backlight_init(struct eeepc_wmi *eeepc)
         memset(&props, 0, sizeof(struct backlight_properties));
         props.max_brightness = 15;
         bd = backlight_device_register(EEEPC_WMI_FILE,
-                                       &platform_device->dev, eeepc,
+                                       &eeepc->platform_device->dev, eeepc,
                                        &eeepc_wmi_bl_ops, &props);
         if (IS_ERR(bd)) {
                 pr_err("Could not register backlight device\n");
@@ -337,49 +339,99 @@ static int eeepc_wmi_sysfs_init(struct platform_device *device)
         return 0;
 
 error_sysfs:
-        eeepc_wmi_sysfs_exit(platform_device);
+        eeepc_wmi_sysfs_exit(device);
         return retval;
 }
 
-static int __devinit eeepc_wmi_platform_probe(struct platform_device *device)
+/*
+ * Platform device
+ */
+static int __init eeepc_wmi_platform_init(struct eeepc_wmi *eeepc)
 {
-        struct eeepc_wmi *eeepc;
         int err;
+
+        eeepc->platform_device = platform_device_alloc(EEEPC_WMI_FILE, -1);
+        if (!eeepc->platform_device)
+                return -ENOMEM;
+        platform_set_drvdata(eeepc->platform_device, eeepc);
+
+        err = platform_device_add(eeepc->platform_device);
+        if (err)
+                goto fail_platform_device;
+
+        err = eeepc_wmi_sysfs_init(eeepc->platform_device);
+        if (err)
+                goto fail_sysfs;
+        return 0;
+
+fail_sysfs:
+        platform_device_del(eeepc->platform_device);
+fail_platform_device:
+        platform_device_put(eeepc->platform_device);
+        return err;
+}
+
+static void eeepc_wmi_platform_exit(struct eeepc_wmi *eeepc)
+{
+        eeepc_wmi_sysfs_exit(eeepc->platform_device);
+        platform_device_unregister(eeepc->platform_device);
+}
+
+/*
+ * WMI Driver
+ */
+static struct platform_device * __init eeepc_wmi_add(void)
+{
+        struct eeepc_wmi *eeepc;
         acpi_status status;
+        int err;
 
-        eeepc = platform_get_drvdata(device);
+        eeepc = kzalloc(sizeof(struct eeepc_wmi), GFP_KERNEL);
+        if (!eeepc)
+                return ERR_PTR(-ENOMEM);
+
+        /*
+         * Register the platform device first.  It is used as a parent for the
+         * sub-devices below.
+         */
+        err = eeepc_wmi_platform_init(eeepc);
+        if (err)
+                goto fail_platform;
 
         err = eeepc_wmi_input_init(eeepc);
         if (err)
-                goto error_input;
+                goto fail_input;
 
         if (!acpi_video_backlight_support()) {
                 err = eeepc_wmi_backlight_init(eeepc);
                 if (err)
-                        goto error_backlight;
+                        goto fail_backlight;
         } else
                 pr_info("Backlight controlled by ACPI video driver\n");
 
         status = wmi_install_notify_handler(EEEPC_WMI_EVENT_GUID,
-                                        eeepc_wmi_notify, eeepc);
+                                            eeepc_wmi_notify, eeepc);
         if (ACPI_FAILURE(status)) {
                 pr_err("Unable to register notify handler - %d\n",
                         status);
                 err = -ENODEV;
-                goto error_wmi;
+                goto fail_wmi_handler;
         }
 
-        return 0;
+        return eeepc->platform_device;
 
-error_wmi:
+fail_wmi_handler:
         eeepc_wmi_backlight_exit(eeepc);
-error_backlight:
+fail_backlight:
         eeepc_wmi_input_exit(eeepc);
-error_input:
-        return err;
+fail_input:
+        eeepc_wmi_platform_exit(eeepc);
+fail_platform:
+        kfree(eeepc);
+        return ERR_PTR(err);
 }
 
-static int __devexit eeepc_wmi_platform_remove(struct platform_device *device)
+static int eeepc_wmi_remove(struct platform_device *device)
 {
         struct eeepc_wmi *eeepc;
 
@@ -387,7 +439,9 @@ static int __devexit eeepc_wmi_platform_remove(struct platform_device *device)
         wmi_remove_notify_handler(EEEPC_WMI_EVENT_GUID);
         eeepc_wmi_backlight_exit(eeepc);
         eeepc_wmi_input_exit(eeepc);
+        eeepc_wmi_platform_exit(eeepc);
 
+        kfree(eeepc);
         return 0;
 }
 
@@ -396,13 +450,10 @@ static struct platform_driver platform_driver = {
                 .name = EEEPC_WMI_FILE,
                 .owner = THIS_MODULE,
         },
-        .probe = eeepc_wmi_platform_probe,
-        .remove = __devexit_p(eeepc_wmi_platform_remove),
 };
 
 static int __init eeepc_wmi_init(void)
 {
-        struct eeepc_wmi *eeepc;
         int err;
 
         if (!wmi_has_guid(EEEPC_WMI_EVENT_GUID) ||
@@ -411,58 +462,30 @@ static int __init eeepc_wmi_init(void)
                 return -ENODEV;
         }
 
-        eeepc = kzalloc(sizeof(struct eeepc_wmi), GFP_KERNEL);
-        if (!eeepc)
-                return -ENOMEM;
-
-        platform_device = platform_device_alloc(EEEPC_WMI_FILE, -1);
-        if (!platform_device) {
-                pr_warning("Unable to allocate platform device\n");
-                err = -ENOMEM;
-                goto fail_platform;
+        platform_device = eeepc_wmi_add();
+        if (IS_ERR(platform_device)) {
+                err = PTR_ERR(platform_device);
+                goto fail_eeepc_wmi;
         }
 
-        err = platform_device_add(platform_device);
-        if (err) {
-                pr_warning("Unable to add platform device\n");
-                goto put_dev;
-        }
-
-        platform_set_drvdata(platform_device, eeepc);
-
         err = platform_driver_register(&platform_driver);
         if (err) {
                 pr_warning("Unable to register platform driver\n");
-                goto del_dev;
+                goto fail_platform_driver;
         }
 
-        err = eeepc_wmi_sysfs_init(platform_device);
-        if (err)
-                goto del_sysfs;
-
         return 0;
 
-del_sysfs:
-        eeepc_wmi_sysfs_exit(platform_device);
-del_dev:
-        platform_device_del(platform_device);
-put_dev:
-        platform_device_put(platform_device);
-fail_platform:
-        kfree(eeepc);
-
+fail_platform_driver:
+        eeepc_wmi_remove(platform_device);
+fail_eeepc_wmi:
         return err;
 }
 
 static void __exit eeepc_wmi_exit(void)
 {
-        struct eeepc_wmi *eeepc;
-
-        eeepc_wmi_sysfs_exit(platform_device);
-        eeepc = platform_get_drvdata(platform_device);
+        eeepc_wmi_remove(platform_device);
         platform_driver_unregister(&platform_driver);
-        platform_device_unregister(platform_device);
-        kfree(eeepc);
 }
 
 module_init(eeepc_wmi_init);