diff --git a/drivers/acpi/ac.c b/drivers/acpi/ac.c
index 98b9690..7725bda 100644
--- a/drivers/acpi/ac.c
+++ b/drivers/acpi/ac.c
@@ -256,11 +256,8 @@ static void acpi_ac_notify(struct acpi_device *device, u32 event)
 static int acpi_ac_add(struct acpi_device *device)
 {
 	int result = 0;
-	struct acpi_ac *ac = NULL;
-
+	struct acpi_ac *ac;
 
-	if (!device)
-		return -EINVAL;
 
 	ac = kzalloc(sizeof(struct acpi_ac), GFP_KERNEL);
 	if (!ac)
@@ -306,11 +303,9 @@ static int acpi_ac_add(struct acpi_device *device)
 
 static int acpi_ac_resume(struct acpi_device *device)
 {
-	struct acpi_ac *ac;
+	struct acpi_ac *ac = acpi_driver_data(device);
 	unsigned old_state;
-	if (!device || !acpi_driver_data(device))
-		return -EINVAL;
-	ac = acpi_driver_data(device);
+
 	old_state = ac->state;
 	if (acpi_ac_get_state(ac))
 		return 0;
@@ -323,13 +318,8 @@ static int acpi_ac_resume(struct acpi_device *device)
 
 static int acpi_ac_remove(struct acpi_device *device, int type)
 {
-	struct acpi_ac *ac = NULL;
-
-
-	if (!device || !acpi_driver_data(device))
-		return -EINVAL;
+	struct acpi_ac *ac = acpi_driver_data(device);
 
-	ac = acpi_driver_data(device);
 
 #ifdef CONFIG_ACPI_SYSFS_POWER
 	if (ac->charger.dev)
diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c
index 28ccdbc..71085b9 100644
--- a/drivers/acpi/acpi_memhotplug.c
+++ b/drivers/acpi/acpi_memhotplug.c
@@ -401,11 +401,8 @@ static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
 static int acpi_memory_device_add(struct acpi_device *device)
 {
 	int result;
-	struct acpi_memory_device *mem_device = NULL;
-
+	struct acpi_memory_device *mem_device;
 
-	if (!device)
-		return -EINVAL;
 
 	mem_device = kzalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
 	if (!mem_device)
@@ -450,13 +447,9 @@ static int acpi_memory_device_add(struct acpi_device *device)
 
 static int acpi_memory_device_remove(struct acpi_device *device, int type)
 {
-	struct acpi_memory_device *mem_device = NULL;
+	struct acpi_memory_device *mem_device = acpi_driver_data(device);
 
 
-	if (!device || !acpi_driver_data(device))
-		return -EINVAL;
-
-	mem_device = acpi_driver_data(device);
 	kfree(mem_device);
 
 	return 0;
diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index 3f4602b..90e39d9 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -840,9 +840,8 @@ static void acpi_battery_notify(struct acpi_device *device, u32 event)
 static int acpi_battery_add(struct acpi_device *device)
 {
 	int result = 0;
-	struct acpi_battery *battery = NULL;
-	if (!device)
-		return -EINVAL;
+	struct acpi_battery *battery;
+
 	battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
 	if (!battery)
 		return -ENOMEM;
@@ -870,11 +869,8 @@ static int acpi_battery_add(struct acpi_device *device)
 
 static int acpi_battery_remove(struct acpi_device *device, int type)
 {
-	struct acpi_battery *battery = NULL;
+	struct acpi_battery *battery = acpi_driver_data(device);
 
-	if (!device || !acpi_driver_data(device))
-		return -EINVAL;
-	battery = acpi_driver_data(device);
 #ifdef CONFIG_ACPI_PROCFS_POWER
 	acpi_battery_remove_fs(device);
 #endif
@@ -889,10 +885,8 @@ static int acpi_battery_remove(struct acpi_device *device, int type)
 /* this is needed to learn about changes made in suspended state */
 static int acpi_battery_resume(struct acpi_device *device)
 {
-	struct acpi_battery *battery;
-	if (!device)
-		return -EINVAL;
-	battery = acpi_driver_data(device);
+	struct acpi_battery *battery = acpi_driver_data(device);
+
 	battery->update_time = 0;
 	acpi_battery_update(battery);
 	return 0;
diff --git a/drivers/acpi/container.c b/drivers/acpi/container.c
index 642bb30..30c4700 100644
--- a/drivers/acpi/container.c
+++ b/drivers/acpi/container.c
@@ -97,11 +97,6 @@ static int acpi_container_add(struct acpi_device *device)
 	struct acpi_container *container;
 
 
-	if (!device) {
-		printk(KERN_ERR PREFIX "device is NULL\n");
-		return -EINVAL;
-	}
-
 	container = kzalloc(sizeof(struct acpi_container), GFP_KERNEL);
 	if (!container)
 		return -ENOMEM;
@@ -120,9 +115,8 @@ static int acpi_container_add(struct acpi_device *device)
 static int acpi_container_remove(struct acpi_device *device, int type)
 {
 	acpi_status status = AE_OK;
-	struct acpi_container *pc = NULL;
+	struct acpi_container *pc = acpi_driver_data(device);
 
-	pc = acpi_driver_data(device);
 	kfree(pc);
 	return status;
 }
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index add6621..5e93ae3 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -837,13 +837,9 @@ static int acpi_ec_add(struct acpi_device *device)
 
 static int acpi_ec_remove(struct acpi_device *device, int type)
 {
-	struct acpi_ec *ec;
+	struct acpi_ec *ec = acpi_driver_data(device);
 	struct acpi_ec_query_handler *handler, *tmp;
 
-	if (!device)
-		return -EINVAL;
-
-	ec = acpi_driver_data(device);
 	ec_remove_handlers(ec);
 	mutex_lock(&ec->lock);
 	list_for_each_entry_safe(handler, tmp, &ec->list, node) {
diff --git a/drivers/acpi/fan.c b/drivers/acpi/fan.c
index f419849..d40e214 100644
--- a/drivers/acpi/fan.c
+++ b/drivers/acpi/fan.c
@@ -244,9 +244,6 @@ static int acpi_fan_add(struct acpi_device *device)
 	int state = 0;
 	struct thermal_cooling_device *cdev;
 
-	if (!device)
-		return -EINVAL;
-
 	strcpy(acpi_device_name(device), "Fan");
 	strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
 
@@ -300,9 +297,6 @@ static int acpi_fan_remove(struct acpi_device *device, int type)
 {
 	struct thermal_cooling_device *cdev = acpi_driver_data(device);
 
-	if (!device || !cdev)
-		return -EINVAL;
-
 	acpi_fan_remove_fs(device);
 	sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 	sysfs_remove_link(&cdev->device.kobj, "device");
@@ -313,9 +307,6 @@ static int acpi_fan_remove(struct acpi_device *device, int type)
 
 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
 {
-	if (!device)
-		return -EINVAL;
-
 	acpi_bus_set_power(device->handle, ACPI_STATE_D0);
 
 	return AE_OK;
@@ -326,9 +317,6 @@ static int acpi_fan_resume(struct acpi_device *device)
 	int result = 0;
 	int power_state = 0;
 
-	if (!device)
-		return -EINVAL;
-
 	result = acpi_bus_get_power(device->handle, &power_state);
 	if (result) {
 		printk(KERN_ERR PREFIX
diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index e86603f..2c3d844 100644
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -639,9 +639,6 @@ static int acpi_power_add(struct acpi_device *device)
 	struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
 
 
-	if (!device)
-		return -EINVAL;
-
 	resource = kzalloc(sizeof(struct acpi_power_resource), GFP_KERNEL);
 	if (!resource)
 		return -ENOMEM;
@@ -695,15 +692,10 @@ static int acpi_power_add(struct acpi_device *device)
 
 static int acpi_power_remove(struct acpi_device *device, int type)
 {
-	struct acpi_power_resource *resource = NULL;
+	struct acpi_power_resource *resource = acpi_driver_data(device);
 	struct list_head *node, *next;
 
 
-	if (!device || !acpi_driver_data(device))
-		return -EINVAL;
-
-	resource = acpi_driver_data(device);
-
 	acpi_power_remove_fs(device);
 
 	mutex_lock(&resource->resource_lock);
@@ -722,14 +714,9 @@ static int acpi_power_remove(struct acpi_device *device, int type)
 static int acpi_power_resume(struct acpi_device *device)
 {
 	int result = 0, state;
-	struct acpi_power_resource *resource = NULL;
+	struct acpi_power_resource *resource = acpi_driver_data(device);
 	struct acpi_power_reference *ref;
 
-	if (!device || !acpi_driver_data(device))
-		return -EINVAL;
-
-	resource = acpi_driver_data(device);
-
 	result = acpi_power_get_state(device->handle, &state);
 	if (result)
 		return result;
diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index c2d4d6e..38ad5ef 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -888,13 +888,8 @@ err_free_cpumask:
 
 static int acpi_processor_remove(struct acpi_device *device, int type)
 {
-	struct acpi_processor *pr = NULL;
-
-
-	if (!device || !acpi_driver_data(device))
-		return -EINVAL;
+	struct acpi_processor *pr = acpi_driver_data(device);
 
-	pr = acpi_driver_data(device);
 
 	if (pr->id >= nr_cpu_ids)
 		goto free;
diff --git a/drivers/acpi/sbs.c b/drivers/acpi/sbs.c
index 52b9db8..4c7ab39 100644
--- a/drivers/acpi/sbs.c
+++ b/drivers/acpi/sbs.c
@@ -960,12 +960,9 @@ static int acpi_sbs_add(struct acpi_device *device)
 
 static int acpi_sbs_remove(struct acpi_device *device, int type)
 {
-	struct acpi_sbs *sbs;
+	struct acpi_sbs *sbs = acpi_driver_data(device);
 	int id;
 
-	if (!device)
-		return -EINVAL;
-	sbs = acpi_driver_data(device);
 	if (!sbs)
 		return -EINVAL;
 	mutex_lock(&sbs->lock);
@@ -996,8 +993,6 @@ static void acpi_sbs_rmdirs(void)
 static int acpi_sbs_resume(struct acpi_device *device)
 {
 	struct acpi_sbs *sbs;
-	if (!device)
-		return -EINVAL;
 	sbs = device->driver_data;
 	acpi_sbs_callback(sbs);
 	return 0;
diff --git a/drivers/acpi/sbshc.c b/drivers/acpi/sbshc.c
index 8d89337..9e06e9c 100644
--- a/drivers/acpi/sbshc.c
+++ b/drivers/acpi/sbshc.c
@@ -262,9 +262,6 @@ static int acpi_smbus_hc_add(struct acpi_device *device)
 	unsigned long long val;
 	struct acpi_smb_hc *hc;
 
-	if (!device)
-		return -EINVAL;
-
 	status = acpi_evaluate_integer(device->handle, "_EC", NULL, &val);
 	if (ACPI_FAILURE(status)) {
 		printk(KERN_ERR PREFIX "error obtaining _EC.\n");
@@ -296,12 +293,8 @@ extern void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit);
 
 static int acpi_smbus_hc_remove(struct acpi_device *device, int type)
 {
-	struct acpi_smb_hc *hc;
-
-	if (!device)
-		return -EINVAL;
+	struct acpi_smb_hc *hc = acpi_driver_data(device);
 
-	hc = acpi_driver_data(device);
 	acpi_ec_remove_query_handler(hc->ec, hc->query_bit);
 	kfree(hc);
 	return 0;
diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
index 65f6781..fca61a1 100644
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -1361,12 +1361,9 @@ static void acpi_thermal_guess_offset(struct acpi_thermal *tz)
 static int acpi_thermal_add(struct acpi_device *device)
 {
 	int result = 0;
-	struct acpi_thermal *tz = NULL;
+	struct acpi_thermal *tz;
 
 
-	if (!device)
-		return -EINVAL;
-
 	tz = kzalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
 	if (!tz)
 		return -ENOMEM;
@@ -1408,12 +1405,7 @@ end:
 
 static int acpi_thermal_remove(struct acpi_device *device, int type)
 {
-	struct acpi_thermal *tz = NULL;
-
-	if (!device || !acpi_driver_data(device))
-		return -EINVAL;
-
-	tz = acpi_driver_data(device);
+	struct acpi_thermal *tz = acpi_driver_data(device);
 
 	acpi_thermal_remove_fs(device);
 	acpi_thermal_unregister_thermal_zone(tz);
@@ -1424,15 +1416,10 @@ static int acpi_thermal_remove(struct acpi_device *device, int type)
 
 static int acpi_thermal_resume(struct acpi_device *device)
 {
-	struct acpi_thermal *tz = NULL;
+	struct acpi_thermal *tz = acpi_driver_data(device);
 	int i, j, power_state, result;
 
 
-	if (!device || !acpi_driver_data(device))
-		return -EINVAL;
-
-	tz = acpi_driver_data(device);
-
 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
 		if (!(&tz->trips.active[i]))
 			break;
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index f405807..576a600 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -2207,15 +2207,10 @@ static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
 static int instance;
 static int acpi_video_resume(struct acpi_device *device)
 {
-	struct acpi_video_bus *video;
+	struct acpi_video_bus *video = acpi_driver_data(device);
 	struct acpi_video_device *video_device;
 	int i;
 
-	if (!device || !acpi_driver_data(device))
-		return -EINVAL;
-
-	video = acpi_driver_data(device);
-
 	for (i = 0; i < video->attached_count; i++) {
 		video_device = video->attached_array[i].bind_info;
 		if (video_device && video_device->backlight)
@@ -2351,13 +2346,8 @@ static int acpi_video_bus_add(struct acpi_device *device)
 
 static int acpi_video_bus_remove(struct acpi_device *device, int type)
 {
-	struct acpi_video_bus *video = NULL;
-
-
-	if (!device || !acpi_driver_data(device))
-		return -EINVAL;
+	struct acpi_video_bus *video = acpi_driver_data(device);
 
-	video = acpi_driver_data(device);
 
 	acpi_video_bus_stop_devices(video);
 	acpi_video_bus_put_devices(video);
diff --git a/drivers/hwmon/hp_accel.c b/drivers/hwmon/hp_accel.c
index 6679854..c8d3c88 100644
--- a/drivers/hwmon/hp_accel.c
+++ b/drivers/hwmon/hp_accel.c
@@ -275,9 +275,6 @@ static int lis3lv02d_add(struct acpi_device *device)
 {
 	int ret;
 
-	if (!device)
-		return -EINVAL;
-
 	lis3_dev.bus_priv = device;
 	lis3_dev.init = lis3lv02d_acpi_init;
 	lis3_dev.read = lis3lv02d_acpi_read;
@@ -315,9 +312,6 @@ static int lis3lv02d_add(struct acpi_device *device)
 
 static int lis3lv02d_remove(struct acpi_device *device, int type)
 {
-	if (!device)
-		return -EINVAL;
-
 	lis3lv02d_joystick_disable();
 	lis3lv02d_poweroff(&lis3_dev);
 
diff --git a/drivers/platform/x86/asus-laptop.c b/drivers/platform/x86/asus-laptop.c
index b39d2bb..8af43e9 100644
--- a/drivers/platform/x86/asus-laptop.c
+++ b/drivers/platform/x86/asus-laptop.c
@@ -1240,9 +1240,6 @@ static int asus_hotk_add(struct acpi_device *device)
 {
 	int result;
 
-	if (!device)
-		return -EINVAL;
-
 	pr_notice("Asus Laptop Support version %s\n",
 	       ASUS_LAPTOP_VERSION);
 
@@ -1306,9 +1303,6 @@ end:
 
 static int asus_hotk_remove(struct acpi_device *device, int type)
 {
-	if (!device || !acpi_driver_data(device))
-		return -EINVAL;
-
 	kfree(hotk->name);
 	kfree(hotk);
 
diff --git a/drivers/platform/x86/asus_acpi.c b/drivers/platform/x86/asus_acpi.c
index ddf5240..25a7d57 100644
--- a/drivers/platform/x86/asus_acpi.c
+++ b/drivers/platform/x86/asus_acpi.c
@@ -1334,9 +1334,6 @@ static int asus_hotk_add(struct acpi_device *device)
 	acpi_status status = AE_OK;
 	int result;
 
-	if (!device)
-		return -EINVAL;
-
 	printk(KERN_NOTICE "Asus Laptop ACPI Extras version %s\n",
 	       ASUS_ACPI_VERSION);
 
@@ -1392,9 +1389,6 @@ end:
 
 static int asus_hotk_remove(struct acpi_device *device, int type)
 {
-	if (!device || !acpi_driver_data(device))
-		return -EINVAL;
-
 	asus_hotk_remove_fs(device);
 
 	kfree(hotk);
diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c
index da3c08b..e7f14a4 100644
--- a/drivers/platform/x86/eeepc-laptop.c
+++ b/drivers/platform/x86/eeepc-laptop.c
@@ -1194,8 +1194,6 @@ static int eeepc_hotk_add(struct acpi_device *device)
 	struct device *dev;
 	int result;
 
-	if (!device)
-		return -EINVAL;
 	pr_notice(EEEPC_HOTK_NAME "\n");
 	ehotk = kzalloc(sizeof(struct eeepc_hotk), GFP_KERNEL);
 	if (!ehotk)
@@ -1276,9 +1274,6 @@ fail_platform_driver:
 
 static int eeepc_hotk_remove(struct acpi_device *device, int type)
 {
-	if (!device || !acpi_driver_data(device))
-		return -EINVAL;
-
 	eeepc_backlight_exit();
 	eeepc_rfkill_exit();
 	eeepc_input_exit();
diff --git a/drivers/platform/x86/fujitsu-laptop.c b/drivers/platform/x86/fujitsu-laptop.c
index f35aee5..2ab0318 100644
--- a/drivers/platform/x86/fujitsu-laptop.c
+++ b/drivers/platform/x86/fujitsu-laptop.c
@@ -657,9 +657,6 @@ static int acpi_fujitsu_add(struct acpi_device *device)
 	struct input_dev *input;
 	int error;
 
-	if (!device)
-		return -EINVAL;
-
 	fujitsu->acpi_handle = device->handle;
 	sprintf(acpi_device_name(device), "%s", ACPI_FUJITSU_DEVICE_NAME);
 	sprintf(acpi_device_class(device), "%s", ACPI_FUJITSU_CLASS);
@@ -813,9 +810,6 @@ static int acpi_fujitsu_hotkey_add(struct acpi_device *device)
 	int error;
 	int i;
 
-	if (!device)
-		return -EINVAL;
-
 	fujitsu_hotkey->acpi_handle = device->handle;
 	sprintf(acpi_device_name(device), "%s",
 		ACPI_FUJITSU_HOTKEY_DEVICE_NAME);
diff --git a/drivers/platform/x86/intel_menlow.c b/drivers/platform/x86/intel_menlow.c
index 29432a5..58de8fd 100644
--- a/drivers/platform/x86/intel_menlow.c
+++ b/drivers/platform/x86/intel_menlow.c
@@ -156,9 +156,6 @@ static int intel_menlow_memory_add(struct acpi_device *device)
 	acpi_handle dummy;
 	struct thermal_cooling_device *cdev;
 
-	if (!device)
-		return -EINVAL;
-
 	status = acpi_get_handle(device->handle, MEMORY_GET_BANDWIDTH, &dummy);
 	if (ACPI_FAILURE(status))
 		goto end;
@@ -200,9 +197,6 @@ static int intel_menlow_memory_remove(struct acpi_device *device, int type)
 {
 	struct thermal_cooling_device *cdev = acpi_driver_data(device);
 
-	if (!device || !cdev)
-		return -EINVAL;
-
 	sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 	sysfs_remove_link(&cdev->device.kobj, "device");
 	thermal_cooling_device_unregister(cdev);
diff --git a/drivers/platform/x86/panasonic-laptop.c b/drivers/platform/x86/panasonic-laptop.c
index fe7cf01..953b60c 100644
--- a/drivers/platform/x86/panasonic-laptop.c
+++ b/drivers/platform/x86/panasonic-laptop.c
@@ -588,9 +588,6 @@ static int acpi_pcc_hotkey_resume(struct acpi_device *device)
 	struct pcc_acpi *pcc = acpi_driver_data(device);
 	acpi_status status = AE_OK;
 
-	if (device == NULL || pcc == NULL)
-		return -EINVAL;
-
 	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Sticky mode restore: %d\n",
 			  pcc->sticky_mode));
 
@@ -604,9 +601,6 @@ static int acpi_pcc_hotkey_add(struct acpi_device *device)
 	struct pcc_acpi *pcc;
 	int num_sifr, result;
 
-	if (!device)
-		return -EINVAL;
-
 	num_sifr = acpi_pcc_get_sqty(device);
 
 	if (num_sifr > 255) {
@@ -703,9 +697,6 @@ static int acpi_pcc_hotkey_remove(struct acpi_device *device, int type)
 {
 	struct pcc_acpi *pcc = acpi_driver_data(device);
 
-	if (!device || !pcc)
-		return -EINVAL;
-
 	sysfs_remove_group(&device->dev.kobj, &pcc_attr_group);
 
 	backlight_device_unregister(pcc->backlight);
