power: supply: ab8500_fg: Allocate wq in probe

The workqueue is allocated in bind() but all interrupts are
registered in probe().

Some interrupts put work on the workqueue, which can have
bad side effects.

Allocate the workqueue in probe() instead, destroy it in
.remove() and make unbind() simply flush the workqueue.

Fixes: 1c1f13a ("power: supply: ab8500: Move to componentized binding")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

Author: Linus Walleij

drivers/power/supply/ab8500_fg.c

@@ -3037,13 +3037,6 @@ static int ab8500_fg_bind(struct device *dev, struct device *master,
 {
 	struct ab8500_fg *di = dev_get_drvdata(dev);
 
-	/* Create a work queue for running the FG algorithm */
-	di->fg_wq = alloc_ordered_workqueue("ab8500_fg_wq", WQ_MEM_RECLAIM);
-	if (di->fg_wq == NULL) {
-		dev_err(dev, "failed to create work queue\n");
-		return -ENOMEM;
-	}
-
 	di->bat_cap.max_mah_design = di->bm->bi->charge_full_design_uah;
 	di->bat_cap.max_mah = di->bat_cap.max_mah_design;
 	di->vbat_nom_uv = di->bm->bi->voltage_max_design_uv;
@@ -3067,8 +3060,7 @@ static void ab8500_fg_unbind(struct device *dev, struct device *master,
 	if (ret)
 		dev_err(dev, "failed to disable coulomb counter\n");
 
-	destroy_workqueue(di->fg_wq);
-	flush_scheduled_work();
+	flush_workqueue(di->fg_wq);
 }
 
 static const struct component_ops ab8500_fg_component_ops = {
@@ -3117,6 +3109,13 @@ static int ab8500_fg_probe(struct platform_device *pdev)
 	ab8500_fg_charge_state_to(di, AB8500_FG_CHARGE_INIT);
 	ab8500_fg_discharge_state_to(di, AB8500_FG_DISCHARGE_INIT);
 
+	/* Create a work queue for running the FG algorithm */
+	di->fg_wq = alloc_ordered_workqueue("ab8500_fg_wq", WQ_MEM_RECLAIM);
+	if (di->fg_wq == NULL) {
+		dev_err(dev, "failed to create work queue\n");
+		return -ENOMEM;
+	}
+
 	/* Init work for running the fg algorithm instantly */
 	INIT_WORK(&di->fg_work, ab8500_fg_instant_work);
 
@@ -3227,6 +3226,8 @@ static int ab8500_fg_remove(struct platform_device *pdev)
 {
 	struct ab8500_fg *di = platform_get_drvdata(pdev);
 
+	destroy_workqueue(di->fg_wq);
+	flush_scheduled_work();
 	component_del(&pdev->dev, &ab8500_fg_component_ops);
 	list_del(&di->node);
 	ab8500_fg_sysfs_exit(di);