memory: renesas-rpc-if: Move resource acquisition to .probe()

While the acquired resources are tied to the lifetime of the RPC-IF core
device (through the use of managed resource functions), the actual
resource acquisition is triggered from the HyperBus and SPI child
drivers.  Due to this mismatch, unbinding and rebinding the child
drivers manually fails with -EBUSY:

    # echo rpc-if-hyperflash > /sys/bus/platform/drivers/rpc-if-hyperflash/unbind
    # echo rpc-if-hyperflash > /sys/bus/platform/drivers/rpc-if-hyperflash/bind
    rpc-if ee200000.spi: can't request region for resource [mem 0xee200000-0xee2001ff]
    rpc-if-hyperflash: probe of rpc-if-hyperflash failed with error -16

The same is true for rpc-if-spi.

Fix this by moving all resource acquisition to the core driver's probe
routine.

Fixes: ca7d8b98 ("memory: add Renesas RPC-IF driver")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/c1012ef1de799e08a70817ab7313794e2d8d7bfb.1669213027.git.geert+renesas@glider.beSigned-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

drivers/memory/renesas-rpc-if.c

@@ -277,32 +277,7 @@ static const struct regmap_config rpcif_regmap_config = {
 
 int rpcif_sw_init(struct rpcif *rpcif, struct device *dev)
 {
-	struct platform_device *pdev = to_platform_device(dev);
 	struct rpcif_priv *rpc = dev_get_drvdata(dev);
-	struct resource *res;
-
-	rpc->base = devm_platform_ioremap_resource_byname(pdev, "regs");
-	if (IS_ERR(rpc->base))
-		return PTR_ERR(rpc->base);
-
-	rpc->regmap = devm_regmap_init(&pdev->dev, NULL, rpc, &rpcif_regmap_config);
-	if (IS_ERR(rpc->regmap)) {
-		dev_err(&pdev->dev,
-			"failed to init regmap for rpcif, error %ld\n",
-			PTR_ERR(rpc->regmap));
-		return	PTR_ERR(rpc->regmap);
-	}
-
-	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dirmap");
-	rpc->dirmap = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(rpc->dirmap))
-		return PTR_ERR(rpc->dirmap);
-	rpc->size = resource_size(res);
-
-	rpc->type = (uintptr_t)of_device_get_match_data(dev);
-	rpc->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
-	if (IS_ERR(rpc->rstc))
-		return PTR_ERR(rpc->rstc);
 
 	rpcif->dev = dev;
 	rpcif->dirmap = rpc->dirmap;
@@ -705,9 +680,11 @@ EXPORT_SYMBOL(rpcif_dirmap_read);
 
 static int rpcif_probe(struct platform_device *pdev)
 {
+	struct device *dev = &pdev->dev;
 	struct platform_device *vdev;
 	struct device_node *flash;
 	struct rpcif_priv *rpc;
+	struct resource *res;
 	const char *name;
 	int ret;
 
@@ -732,6 +709,28 @@ static int rpcif_probe(struct platform_device *pdev)
 	if (!rpc)
 		return -ENOMEM;
 
+	rpc->base = devm_platform_ioremap_resource_byname(pdev, "regs");
+	if (IS_ERR(rpc->base))
+		return PTR_ERR(rpc->base);
+
+	rpc->regmap = devm_regmap_init(dev, NULL, rpc, &rpcif_regmap_config);
+	if (IS_ERR(rpc->regmap)) {
+		dev_err(dev, "failed to init regmap for rpcif, error %ld\n",
+			PTR_ERR(rpc->regmap));
+		return	PTR_ERR(rpc->regmap);
+	}
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dirmap");
+	rpc->dirmap = devm_ioremap_resource(dev, res);
+	if (IS_ERR(rpc->dirmap))
+		return PTR_ERR(rpc->dirmap);
+	rpc->size = resource_size(res);
+
+	rpc->type = (uintptr_t)of_device_get_match_data(dev);
+	rpc->rstc = devm_reset_control_get_exclusive(dev, NULL);
+	if (IS_ERR(rpc->rstc))
+		return PTR_ERR(rpc->rstc);
+
 	vdev = platform_device_alloc(name, pdev->id);
 	if (!vdev)
 		return -ENOMEM;