ACPI: button: Switch over to devres-based resource management

Switch over the ACPI button driver to devres-based resource management
by making the following changes:

 * Use devm_kzalloc() for allocating button object memory.

 * Use devm_input_allocate_device() for allocating the input class
   device object.

 * Turn acpi_lid_remove_fs() into a devm cleanup action added
   by devm_acpi_lid_add_fs() which is a new wrapper around
   acpi_lid_add_fs().

 * Add devm_acpi_button_init_wakeup() for initializing the wakeup source
   and make it add a custom devm action that will automatically remove
   the wakeup source registered by it.

 * Turn acpi_button_remove_event_handler() into a devm cleanup action
   added by devm_acpi_button_add_event_handler() which is a new wrapper
   around acpi_button_add_event_handler().

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/2283436.Mh6RI2rZIc@rafael.j.wysocki
[ rjw: Rebased and removed unnecessary input device parent assignment ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c
index a948d046fbcb4ed9803d891909ef598200185a9c..3836ee75dd66e81ed5cf5eb3ad42803872bdb663 100644 (file)
--- a/drivers/acpi/button.c
+++ b/drivers/acpi/button.c
@@ -340,8 +340,9 @@ remove_button_dir:
        return -ENODEV;
 }
 
-static void acpi_lid_remove_fs(struct acpi_button *button)
+static void acpi_lid_remove_fs(void *data)
 {
+       struct acpi_button *button = data;
        struct acpi_device *device = button->adev;
 
        remove_proc_entry(ACPI_BUTTON_FILE_STATE,
@@ -355,6 +356,17 @@ static void acpi_lid_remove_fs(struct acpi_button *button)
        acpi_button_dir = NULL;
 }
 
+static int devm_acpi_lid_add_fs(struct device *dev, struct acpi_button *button)
+{
+       int ret;
+
+       ret = acpi_lid_add_fs(button);
+       if (ret)
+               return ret;
+
+       return devm_add_action_or_reset(dev, acpi_lid_remove_fs, button);
+}
+
 static acpi_handle saved_lid_handle;
 static DEFINE_MUTEX(acpi_lid_lock);
 
@@ -530,8 +542,20 @@ static acpi_notify_handler acpi_button_notify_handler(struct acpi_button *button
        return acpi_button_notify;
 }
 
-static void acpi_button_remove_event_handler(struct acpi_button *button)
+static void acpi_button_wakeup_cleanup(void *data)
+{
+       device_init_wakeup(data, false);
+}
+
+static int devm_acpi_button_init_wakeup(struct device *dev)
 {
+       device_init_wakeup(dev, true);
+       return devm_add_action_or_reset(dev, acpi_button_wakeup_cleanup, dev);
+}
+
+static void acpi_button_remove_event_handler(void *data)
+{
+       struct acpi_button *button = data;
        struct acpi_device *adev = button->adev;
 
        switch (adev->device_type) {
@@ -608,6 +632,19 @@ static int acpi_button_add_event_handler(struct acpi_button *button)
        return 0;
 }
 
+static int devm_acpi_button_add_event_handler(struct device *dev,
+                                             struct acpi_button *button)
+{
+       int ret;
+
+       ret = acpi_button_add_event_handler(button);
+       if (ret)
+               return ret;
+
+       return devm_add_action_or_reset(dev, acpi_button_remove_event_handler,
+                                       button);
+}
+
 static int acpi_button_probe(struct platform_device *pdev)
 {
        struct device *dev = &pdev->dev;
@@ -627,7 +664,7 @@ static int acpi_button_probe(struct platform_device *pdev)
            lid_init_state == ACPI_BUTTON_LID_INIT_DISABLED)
                return -ENODEV;
 
-       button = kzalloc_obj(struct acpi_button);
+       button = devm_kzalloc(dev, sizeof(*button), GFP_KERNEL);
        if (!button)
                return -ENOMEM;
 
@@ -635,11 +672,10 @@ static int acpi_button_probe(struct platform_device *pdev)
 
        button->dev = dev;
        button->adev = device;
-       input = input_allocate_device();
-       if (!input) {
-               error = -ENOMEM;
-               goto err_free_button;
-       }
+       input = devm_input_allocate_device(dev);
+       if (!input)
+               return -ENOMEM;
+
        button->input = input;
        button->type = button_type;
 
@@ -651,11 +687,10 @@ static int acpi_button_probe(struct platform_device *pdev)
                input_set_capability(input, EV_SW, SW_LID);
                input->open = acpi_lid_input_open;
 
-               error = acpi_lid_add_fs(button);
-               if (error) {
-                       input_free_device(input);
-                       goto err_free_button;
-               }
+               error = devm_acpi_lid_add_fs(dev, button);
+               if (error)
+                       return error;
+
                break;
 
        case ACPI_BUTTON_TYPE_POWER:
@@ -674,9 +709,7 @@ static int acpi_button_probe(struct platform_device *pdev)
                break;
 
        default:
-               input_free_device(input);
-               error = dev_err_probe(dev, -ENODEV, "Unrecognized button type\n");
-               goto err_free_button;
+               return dev_err_probe(dev, -ENODEV, "Unrecognized button type\n");
        }
 
        snprintf(button->phys, sizeof(button->phys), "%s/button/input0",
@@ -685,20 +718,19 @@ static int acpi_button_probe(struct platform_device *pdev)
        input->phys = button->phys;
        input->id.bustype = BUS_HOST;
        input->id.product = button_type;
-       input->dev.parent = dev;
 
        input_set_drvdata(input, button);
        error = input_register_device(input);
-       if (error) {
-               input_free_device(input);
-               goto err_remove_fs;
-       }
+       if (error)
+               return error;
 
-       device_init_wakeup(button->dev, true);
+       error = devm_acpi_button_init_wakeup(dev);
+       if (error)
+               return error;
 
-       error = acpi_button_add_event_handler(button);
+       error = devm_acpi_button_add_event_handler(dev, button);
        if (error)
-               goto err_input_unregister;
+               return error;
 
        if (button_type == ACPI_BUTTON_TYPE_LID) {
                /*
@@ -709,37 +741,16 @@ static int acpi_button_probe(struct platform_device *pdev)
        }
 
        pr_info("%s [%s]\n", input->name, acpi_device_bid(device));
-       return 0;
 
-err_input_unregister:
-       device_init_wakeup(button->dev, false);
-       input_unregister_device(input);
-err_remove_fs:
-       if (button_type == ACPI_BUTTON_TYPE_LID)
-               acpi_lid_remove_fs(button);
-
-err_free_button:
-       kfree(button);
-       return error;
+       return 0;
 }
 
 static void acpi_button_remove(struct platform_device *pdev)
 {
        struct acpi_button *button = platform_get_drvdata(pdev);
-       struct acpi_device *adev = button->adev;
-
-       if (button->type == ACPI_BUTTON_TYPE_LID)
-               acpi_lid_forget(adev);
-
-       acpi_button_remove_event_handler(button);
 
-       device_init_wakeup(button->dev, false);
-
-       input_unregister_device(button->input);
        if (button->type == ACPI_BUTTON_TYPE_LID)
-               acpi_lid_remove_fs(button);
-
-       kfree(button);
+               acpi_lid_forget(button->adev);
 }
 
 static int param_set_lid_init_state(const char *val,