platform/x86: fujitsu-laptop: allocate fujitsu_bl in acpi_fujitsu_bl_add()

Only allocate memory for struct fujitsu_bl when the FUJ02B1 ACPI device
is present.  Use devm_kzalloc() for allocating memory to simplify
cleanup.

Due to the fact that the power property of the backlight device created
by the backlight driver is accessed from acpi_fujitsu_laptop_add(),
pointer to the allocated memory will remain stored in a module-wide
variable until the backlight driver is extracted into a separate module.

Signed-off-by: Michał Kępień <kernel@kempniu.pl>
Reviewed-by: Jonathan Woithe <jwoithe@just42.net>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>

diff --git a/drivers/platform/x86/fujitsu-laptop.c b/drivers/platform/x86/fujitsu-laptop.c
index 024ef339179a8971afb98ef53a80449ced22de51..63a9b98967faa52cb22e7fab0802a7fc95912c81 100644 (file)
--- a/drivers/platform/x86/fujitsu-laptop.c
+++ b/drivers/platform/x86/fujitsu-laptop.c
@@ -392,6 +392,7 @@ static int fujitsu_backlight_register(struct acpi_device *device)
 
 static int acpi_fujitsu_bl_add(struct acpi_device *device)
 {
+       struct fujitsu_bl *priv;
        int state = 0;
        int error;
 
@@ -401,10 +402,15 @@ static int acpi_fujitsu_bl_add(struct acpi_device *device)
        if (!device)
                return -EINVAL;
 
+       priv = devm_kzalloc(&device->dev, sizeof(*priv), GFP_KERNEL);
+       if (!priv)
+               return -ENOMEM;
+
+       fujitsu_bl = priv;
        fujitsu_bl->acpi_handle = device->handle;
        sprintf(acpi_device_name(device), "%s", ACPI_FUJITSU_BL_DEVICE_NAME);
        sprintf(acpi_device_class(device), "%s", ACPI_FUJITSU_CLASS);
-       device->driver_data = fujitsu_bl;
+       device->driver_data = priv;
 
        error = acpi_fujitsu_bl_input_setup(device);
        if (error)
@@ -837,7 +843,7 @@ static int acpi_fujitsu_laptop_add(struct acpi_device *device)
        pr_info("BTNI: [0x%x]\n", call_fext_func(FUNC_BUTTONS, 0x0, 0x0, 0x0));
 
        /* Sync backlight power status */
-       if (fujitsu_bl->bl_device &&
+       if (fujitsu_bl && fujitsu_bl->bl_device &&
            acpi_video_get_backlight_type() == acpi_backlight_vendor) {
                if (call_fext_func(FUNC_BACKLIGHT, 0x2, 0x4, 0x0) == 3)
                        fujitsu_bl->bl_device->props.power = FB_BLANK_POWERDOWN;
@@ -995,13 +1001,9 @@ static int __init fujitsu_init(void)
        if (acpi_disabled)
                return -ENODEV;
 
-       fujitsu_bl = kzalloc(sizeof(struct fujitsu_bl), GFP_KERNEL);
-       if (!fujitsu_bl)
-               return -ENOMEM;
-
        ret = acpi_bus_register_driver(&acpi_fujitsu_bl_driver);
        if (ret)
-               goto err_free_fujitsu_bl;
+               return ret;
 
        /* Register platform stuff */
 
@@ -1031,8 +1033,6 @@ static int __init fujitsu_init(void)
        platform_driver_unregister(&fujitsu_pf_driver);
 err_unregister_acpi:
        acpi_bus_unregister_driver(&acpi_fujitsu_bl_driver);
-err_free_fujitsu_bl:
-       kfree(fujitsu_bl);
 
        return ret;
 }
@@ -1047,8 +1047,6 @@ static void __exit fujitsu_cleanup(void)
 
        acpi_bus_unregister_driver(&acpi_fujitsu_bl_driver);
 
-       kfree(fujitsu_bl);
-
        pr_info("driver unloaded\n");
 }