reset: th1520: Prepare for supporting multiple controllers

TH1520 SoC is divided into several subsystems, shipping distinct reset
controllers with similar control logic. Let's make reset signal mapping
a data structure specific to one compatible to prepare for introduction
of more reset controllers in the future.

Signed-off-by: Yao Zi <ziyao@disroot.org>
Acked-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Drew Fustini <fustini@kernel.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

Author: ziyao233

drivers/reset/reset-th1520.c

@@ -29,14 +29,20 @@
 #define TH1520_HDMI_SW_MAIN_RST		BIT(0)
 #define TH1520_HDMI_SW_PRST		BIT(1)
 
+struct th1520_reset_map {
+	u32 bit;
+	u32 reg;
+};
+
 struct th1520_reset_priv {
 	struct reset_controller_dev rcdev;
 	struct regmap *map;
+	const struct th1520_reset_map *resets;
 };
 
-struct th1520_reset_map {
-	u32 bit;
-	u32 reg;
+struct th1520_reset_data {
+	const struct th1520_reset_map *resets;
+	size_t num;
 };
 
 static const struct th1520_reset_map th1520_resets[] = {
@@ -90,7 +96,7 @@ static int th1520_reset_assert(struct reset_controller_dev *rcdev,
 	struct th1520_reset_priv *priv = to_th1520_reset(rcdev);
 	const struct th1520_reset_map *reset;
 
-	reset = &th1520_resets[id];
+	reset = &priv->resets[id];
 
 	return regmap_update_bits(priv->map, reset->reg, reset->bit, 0);
 }
@@ -101,7 +107,7 @@ static int th1520_reset_deassert(struct reset_controller_dev *rcdev,
 	struct th1520_reset_priv *priv = to_th1520_reset(rcdev);
 	const struct th1520_reset_map *reset;
 
-	reset = &th1520_resets[id];
+	reset = &priv->resets[id];
 
 	return regmap_update_bits(priv->map, reset->reg, reset->bit,
 				  reset->bit);
@@ -120,11 +126,14 @@ static const struct regmap_config th1520_reset_regmap_config = {
 
 static int th1520_reset_probe(struct platform_device *pdev)
 {
+	const struct th1520_reset_data *data;
 	struct device *dev = &pdev->dev;
 	struct th1520_reset_priv *priv;
 	void __iomem *base;
 	int ret;
 
+	data = device_get_match_data(dev);
+
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
@@ -138,22 +147,31 @@ static int th1520_reset_probe(struct platform_device *pdev)
 	if (IS_ERR(priv->map))
 		return PTR_ERR(priv->map);
 
-	/* Initialize GPU resets to asserted state */
-	ret = regmap_update_bits(priv->map, TH1520_GPU_RST_CFG,
-				 TH1520_GPU_RST_CFG_MASK, 0);
-	if (ret)
-		return ret;
+	if (of_device_is_compatible(dev->of_node, "thead,th1520-reset")) {
+		/* Initialize GPU resets to asserted state */
+		ret = regmap_update_bits(priv->map, TH1520_GPU_RST_CFG,
+					 TH1520_GPU_RST_CFG_MASK, 0);
+		if (ret)
+			return ret;
+	}
 
 	priv->rcdev.owner = THIS_MODULE;
-	priv->rcdev.nr_resets = ARRAY_SIZE(th1520_resets);
+	priv->rcdev.nr_resets = data->num;
 	priv->rcdev.ops = &th1520_reset_ops;
 	priv->rcdev.of_node = dev->of_node;
 
+	priv->resets = data->resets;
+
 	return devm_reset_controller_register(dev, &priv->rcdev);
 }
 
+static const struct th1520_reset_data th1520_reset_data = {
+	.resets = th1520_resets,
+	.num = ARRAY_SIZE(th1520_resets),
+};
+
 static const struct of_device_id th1520_reset_match[] = {
-	{ .compatible = "thead,th1520-reset" },
+	{ .compatible = "thead,th1520-reset", .data = &th1520_reset_data },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, th1520_reset_match);