mtd: nand: qcom: reorganize nand devices probing

The NAND controller can support multiple NAND devices having different
page sizes. Future code will require us to allocate memory based on the
maximum number of codewords among all the devices. We reorganize the
NAND device probing such that the ONFI parameters are first read for
each connected device to identify the maximum number of codewords
possible, and only then proceed with MTD device registration (i.e, call
nand_scan_tail and mtd_device_register).

This is a reorganization of the existing code and will not change any
functionality.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

drivers/mtd/nand/qcom_nandc.c

@@ -2057,14 +2057,67 @@ static int qcom_nand_host_init(struct qcom_nand_controller *nandc,
 		return ret;
 
 	ret = qcom_nand_host_setup(host);
-	if (ret)
-		return ret;
+
+	return ret;
+}
+
+static int qcom_nand_mtd_register(struct qcom_nand_controller *nandc,
+				  struct qcom_nand_host *host,
+				  struct device_node *dn)
+{
+	struct nand_chip *chip = &host->chip;
+	struct mtd_info *mtd = nand_to_mtd(chip);
+	int ret;
 
 	ret = nand_scan_tail(mtd);
 	if (ret)
 		return ret;
 
-	return mtd_device_register(mtd, NULL, 0);
+	ret = mtd_device_register(mtd, NULL, 0);
+	if (ret)
+		nand_cleanup(mtd_to_nand(mtd));
+
+	return ret;
+}
+
+static int qcom_probe_nand_devices(struct qcom_nand_controller *nandc)
+{
+	struct device *dev = nandc->dev;
+	struct device_node *dn = dev->of_node, *child;
+	struct qcom_nand_host *host, *tmp;
+	int ret;
+
+	for_each_available_child_of_node(dn, child) {
+		host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
+		if (!host) {
+			of_node_put(child);
+			return -ENOMEM;
+		}
+
+		ret = qcom_nand_host_init(nandc, host, child);
+		if (ret) {
+			devm_kfree(dev, host);
+			continue;
+		}
+
+		list_add_tail(&host->node, &nandc->host_list);
+	}
+
+	if (list_empty(&nandc->host_list))
+		return -ENODEV;
+
+	list_for_each_entry_safe(host, tmp, &nandc->host_list, node) {
+		ret = qcom_nand_mtd_register(nandc, host, child);
+		if (ret) {
+			list_del(&host->node);
+			devm_kfree(dev, host);
+		}
+	}
+
+	if (list_empty(&nandc->host_list))
+		return -ENODEV;
+
+	return 0;
 }
 
 /* parse custom DT properties here */
@@ -2092,10 +2145,8 @@ static int qcom_nandc_parse_dt(struct platform_device *pdev)
 static int qcom_nandc_probe(struct platform_device *pdev)
 {
 	struct qcom_nand_controller *nandc;
-	struct qcom_nand_host *host;
 	const void *dev_data;
 	struct device *dev = &pdev->dev;
-	struct device_node *dn = dev->of_node, *child;
 	struct resource *res;
 	int ret;
 
@@ -2149,33 +2200,12 @@ static int qcom_nandc_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_setup;
 
-	for_each_available_child_of_node(dn, child) {
-		host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
-		if (!host) {
-			of_node_put(child);
-			ret = -ENOMEM;
-			goto err_cs_init;
-		}
-
-		ret = qcom_nand_host_init(nandc, host, child);
-		if (ret) {
-			devm_kfree(dev, host);
-			continue;
-		}
-
-		list_add_tail(&host->node, &nandc->host_list);
-	}
-
-	if (list_empty(&nandc->host_list)) {
-		ret = -ENODEV;
-		goto err_cs_init;
-	}
+	ret = qcom_probe_nand_devices(nandc);
+	if (ret)
+		goto err_setup;
 
 	return 0;
 
-err_cs_init:
-	list_for_each_entry(host, &nandc->host_list, node)
-		nand_release(nand_to_mtd(&host->chip));
 err_setup:
 	clk_disable_unprepare(nandc->aon_clk);
 err_aon_clk: