[PATCH] Input: mtk-pmic-keys: Use flexible array member for keys

[Rosen Penev]

Convert the fixed-size keys array to a flexible array member and use
struct_size() for allocation. Move the key count validation before
allocation and use for_each_available_child_of_node_scoped() to iterate
only over available child nodes as the allocation uses
of_get_available_child_count.

Also use a key variable in the loop for clarity.

Use of_device_get_match_data() to fetch the PMIC key register data directly
instead of open-coding an of_match_device() lookup.

This also lets the driver drop the of_device.h include.

Remove platform_set_drvdata. Unused anywhere.

Assisted-by: OpenCode:BigPickle
Signed-off-by: Rosen Penev <rosenp@xxxxxxxxx>
---
 drivers/input/keyboard/mtk-pmic-keys.c | 55 ++++++++++++--------------
 1 file changed, 25 insertions(+), 30 deletions(-)

diff --git a/drivers/input/keyboard/mtk-pmic-keys.c b/drivers/input/keyboard/mtk-pmic-keys.c
index c78d9f6d97c4..5b8650f46105 100644
--- a/drivers/input/keyboard/mtk-pmic-keys.c
+++ b/drivers/input/keyboard/mtk-pmic-keys.c
@@ -16,7 +16,6 @@
 #include <linux/mfd/mt6397/core.h>
 #include <linux/mfd/mt6397/registers.h>
 #include <linux/module.h>
-#include <linux/of_device.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
@@ -147,7 +146,7 @@ struct mtk_pmic_keys {
 	struct input_dev *input_dev;
 	struct device *dev;
 	struct regmap *regmap;
-	struct mtk_pmic_keys_info keys[MTK_PMIC_MAX_KEY_COUNT];
+	struct mtk_pmic_keys_info keys[];
 };
 
 enum mtk_pmic_keys_lp_mode {
@@ -332,17 +331,25 @@ static int mtk_pmic_keys_probe(struct platform_device *pdev)
 	static const char *const irqnames_r[] = { "powerkey_r", "homekey_r" };
 	struct mtk_pmic_keys *keys;
 	const struct mtk_pmic_regs *mtk_pmic_regs;
+	struct mtk_pmic_keys_info *key;
 	struct input_dev *input_dev;
-	const struct of_device_id *of_id =
-		of_match_device(of_mtk_pmic_keys_match_tbl, &pdev->dev);
 
-	keys = devm_kzalloc(&pdev->dev, sizeof(*keys), GFP_KERNEL);
+	keycount = of_get_available_child_count(node);
+	if (keycount > MTK_PMIC_MAX_KEY_COUNT ||
+	    keycount > ARRAY_SIZE(irqnames)) {
+		dev_err(&pdev->dev, "too many keys defined (%d)\n", keycount);
+		return -EINVAL;
+	}
+
+	keys = devm_kzalloc(&pdev->dev, struct_size(keys, keys, keycount), GFP_KERNEL);
 	if (!keys)
 		return -ENOMEM;
 
 	keys->dev = &pdev->dev;
 	keys->regmap = pmic_chip->regmap;
-	mtk_pmic_regs = of_id->data;
+	mtk_pmic_regs = of_device_get_match_data(&pdev->dev);
+	if (!mtk_pmic_regs)
+		return -EINVAL;
 
 	keys->input_dev = input_dev = devm_input_allocate_device(keys->dev);
 	if (!input_dev) {
@@ -356,31 +363,21 @@ static int mtk_pmic_keys_probe(struct platform_device *pdev)
 	input_dev->id.product = 0x0001;
 	input_dev->id.version = 0x0001;
 
-	keycount = of_get_available_child_count(node);
-	if (keycount > MTK_PMIC_MAX_KEY_COUNT ||
-	    keycount > ARRAY_SIZE(irqnames)) {
-		dev_err(keys->dev, "too many keys defined (%d)\n", keycount);
-		return -EINVAL;
-	}
+	for_each_available_child_of_node_scoped(node, child) {
+		key = &keys->keys[index];
+		key->regs = &mtk_pmic_regs->keys_regs[index];
 
-	for_each_child_of_node_scoped(node, child) {
-		keys->keys[index].regs = &mtk_pmic_regs->keys_regs[index];
-
-		keys->keys[index].irq =
-			platform_get_irq_byname(pdev, irqnames[index]);
-		if (keys->keys[index].irq < 0)
-			return keys->keys[index].irq;
+		key->irq = platform_get_irq_byname(pdev, irqnames[index]);
+		if (key->irq < 0)
+			return key->irq;
 
 		if (mtk_pmic_regs->key_release_irq) {
-			keys->keys[index].irq_r = platform_get_irq_byname(pdev,
-									  irqnames_r[index]);
-
-			if (keys->keys[index].irq_r < 0)
-				return keys->keys[index].irq_r;
+			key->irq_r = platform_get_irq_byname(pdev, irqnames_r[index]);
+			if (key->irq_r < 0)
+				return key->irq_r;
 		}
 
-		error = of_property_read_u32(child,
-			"linux,keycodes", &keys->keys[index].keycode);
+		error = of_property_read_u32(child, "linux,keycodes", &key->keycode);
 		if (error) {
 			dev_err(keys->dev,
 				"failed to read key:%d linux,keycode property: %d\n",
@@ -389,9 +386,9 @@ static int mtk_pmic_keys_probe(struct platform_device *pdev)
 		}
 
 		if (of_property_read_bool(child, "wakeup-source"))
-			keys->keys[index].wakeup = true;
+			key->wakeup = true;
 
-		error = mtk_pmic_key_setup(keys, &keys->keys[index]);
+		error = mtk_pmic_key_setup(keys, key);
 		if (error)
 			return error;
 
@@ -407,8 +404,6 @@ static int mtk_pmic_keys_probe(struct platform_device *pdev)
 
 	mtk_pmic_keys_lp_reset_setup(keys, mtk_pmic_regs);
 
-	platform_set_drvdata(pdev, keys);
-
 	return 0;
 }
 
-- 
2.54.0