Input: cobalt_btns - convert to use managed resources

This simplifies error handling and allows to remove cobalt_buttons_remove()
method.

Link: https://lore.kernel.org/r/20191017204217.106453-12-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/misc/cobalt_btns.c

@@ -5,6 +5,7 @@
  *  Copyright (C) 2007-2008  Yoichi Yuasa <yuasa@linux-mips.org>
  */
 #include <linux/input-polldev.h>
+#include <linux/io.h>
 #include <linux/ioport.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
@@ -26,7 +27,6 @@ static const unsigned short cobalt_map[] = {
 };
 
 struct buttons_dev {
-	struct input_polled_dev *poll_dev;
 	unsigned short keymap[ARRAY_SIZE(cobalt_map)];
 	int count[ARRAY_SIZE(cobalt_map)];
 	void __iomem *reg;
@@ -67,15 +67,24 @@ static int cobalt_buttons_probe(struct platform_device *pdev)
 	struct resource *res;
 	int error, i;
 
-	bdev = kzalloc(sizeof(struct buttons_dev), GFP_KERNEL);
-	poll_dev = input_allocate_polled_device();
-	if (!bdev || !poll_dev) {
-		error = -ENOMEM;
-		goto err_free_mem;
-	}
+	bdev = devm_kzalloc(&pdev->dev, sizeof(*bdev), GFP_KERNEL);
+	if (!bdev)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -EBUSY;
+
+	bdev->reg = devm_ioremap(&pdev->dev, res->start, resource_size(res));
+	if (!bdev->reg)
+		return -ENOMEM;
 
 	memcpy(bdev->keymap, cobalt_map, sizeof(bdev->keymap));
 
+	poll_dev = devm_input_allocate_polled_device(&pdev->dev);
+	if (!poll_dev)
+		return -ENOMEM;
+
 	poll_dev->private = bdev;
 	poll_dev->poll = handle_buttons;
 	poll_dev->poll_interval = BUTTONS_POLL_INTERVAL;
@@ -84,7 +93,6 @@ static int cobalt_buttons_probe(struct platform_device *pdev)
 	input->name = "Cobalt buttons";
 	input->phys = "cobalt/input0";
 	input->id.bustype = BUS_HOST;
-	input->dev.parent = &pdev->dev;
 
 	input->keycode = bdev->keymap;
 	input->keycodemax = ARRAY_SIZE(bdev->keymap);
@@ -96,39 +104,9 @@ static int cobalt_buttons_probe(struct platform_device *pdev)
 		__set_bit(bdev->keymap[i], input->keybit);
 	__clear_bit(KEY_RESERVED, input->keybit);
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res) {
-		error = -EBUSY;
-		goto err_free_mem;
-	}
-
-	bdev->poll_dev = poll_dev;
-	bdev->reg = ioremap(res->start, resource_size(res));
-	dev_set_drvdata(&pdev->dev, bdev);
-
 	error = input_register_polled_device(poll_dev);
 	if (error)
-		goto err_iounmap;
-
-	return 0;
-
- err_iounmap:
-	iounmap(bdev->reg);
- err_free_mem:
-	input_free_polled_device(poll_dev);
-	kfree(bdev);
-	return error;
-}
-
-static int cobalt_buttons_remove(struct platform_device *pdev)
-{
-	struct device *dev = &pdev->dev;
-	struct buttons_dev *bdev = dev_get_drvdata(dev);
-
-	input_unregister_polled_device(bdev->poll_dev);
-	input_free_polled_device(bdev->poll_dev);
-	iounmap(bdev->reg);
-	kfree(bdev);
+		return error;
 
 	return 0;
 }
@@ -141,7 +119,6 @@ MODULE_ALIAS("platform:Cobalt buttons");
 
 static struct platform_driver cobalt_buttons_driver = {
 	.probe	= cobalt_buttons_probe,
-	.remove	= cobalt_buttons_remove,
 	.driver	= {
 		.name	= "Cobalt buttons",
 	},