[PATCH 12/58] mtd: rawnand: arasan: retain chips across controller removal

[James Hilliard]

Keep chip metadata, BCH state and controller storage until the last MTD
reference is released. Unregister and disconnect the chips before
releasing chip-select GPIOs, so notifier I/O and active NAND operations
finish while the hardware is usable.

Free unpublished chip allocations directly and use retained cleanup
after MTD registration has been attempted.

Fixes: 197b88fecc50 ("mtd: rawnand: arasan: Add new Arasan NAND controller")
Signed-off-by: James Hilliard <james.hilliard1 at gmail.com>
---
 drivers/mtd/nand/raw/arasan-nand-controller.c | 57 ++++++++++++++++++++-------
 1 file changed, 42 insertions(+), 15 deletions(-)

diff --git a/drivers/mtd/nand/raw/arasan-nand-controller.c b/drivers/mtd/nand/raw/arasan-nand-controller.c
index 865754737f5f..57b5d6119b70 100644
--- a/drivers/mtd/nand/raw/arasan-nand-controller.c
+++ b/drivers/mtd/nand/raw/arasan-nand-controller.c
@@ -1269,6 +1269,11 @@ static const struct nand_controller_ops anfc_ops = {
 	.detach_chip = anfc_detach_chip,
 };
 
+static void anfc_chip_release(struct nand_chip *chip)
+{
+	kfree(to_anand(chip));
+}
+
 static int anfc_chip_init(struct arasan_nfc *nfc, struct device_node *np)
 {
 	struct anand *anand;
@@ -1276,7 +1281,7 @@ static int anfc_chip_init(struct arasan_nfc *nfc, struct device_node *np)
 	struct mtd_info *mtd;
 	int rb, ret, i;
 
-	anand = devm_kzalloc(nfc->dev, sizeof(*anand), GFP_KERNEL);
+	anand = kzalloc_obj(*anand);
 	if (!anand)
 		return -ENOMEM;
 
@@ -1284,31 +1289,35 @@ static int anfc_chip_init(struct arasan_nfc *nfc, struct device_node *np)
 	anand->ncs_idx = of_property_count_elems_of_size(np, "reg", sizeof(u32));
 	if (anand->ncs_idx <= 0 || anand->ncs_idx > nfc->ncs) {
 		dev_err(nfc->dev, "Invalid reg property\n");
-		return -EINVAL;
+		ret = -EINVAL;
+		goto free_chip;
 	}
 
 	anand->cs_idx = devm_kcalloc(nfc->dev, anand->ncs_idx,
 				     sizeof(*anand->cs_idx), GFP_KERNEL);
-	if (!anand->cs_idx)
-		return -ENOMEM;
+	if (!anand->cs_idx) {
+		ret = -ENOMEM;
+		goto free_chip;
+	}
 
 	for (i = 0; i < anand->ncs_idx; i++) {
 		ret = of_property_read_u32_index(np, "reg", i,
 						 &anand->cs_idx[i]);
 		if (ret) {
 			dev_err(nfc->dev, "invalid CS property: %d\n", ret);
-			return ret;
+			goto free_chip;
 		}
 	}
 
 	/* Ready-busy init */
 	ret = of_property_read_u32(np, "nand-rb", &rb);
 	if (ret)
-		return ret;
+		goto free_chip;
 
 	if (rb >= ANFC_MAX_CS) {
 		dev_err(nfc->dev, "Wrong RB %d\n", rb);
-		return -EINVAL;
+		ret = -EINVAL;
+		goto free_chip;
 	}
 
 	anand->rb = rb;
@@ -1323,24 +1332,35 @@ static int anfc_chip_init(struct arasan_nfc *nfc, struct device_node *np)
 	nand_set_flash_node(chip, np);
 	if (!mtd->name) {
 		dev_err(nfc->dev, "NAND label property is mandatory\n");
-		return -EINVAL;
+		ret = -EINVAL;
+		goto free_chip;
 	}
 
 	ret = nand_scan(chip, anand->ncs_idx);
 	if (ret) {
 		dev_err(nfc->dev, "Scan operation failed\n");
-		return ret;
+		goto free_chip;
 	}
 
-	ret = mtd_device_register(mtd, NULL, 0);
+	ret = nand_set_release(chip, anfc_chip_release);
 	if (ret) {
 		nand_cleanup(chip);
+		goto free_chip;
+	}
+	ret = mtd_device_register(mtd, NULL, 0);
+	if (ret) {
+		nand_disconnect(chip);
+		mtd_put_master(mtd);
 		return ret;
 	}
 
 	list_add_tail(&anand->node, &nfc->chips);
 
 	return 0;
+
+free_chip:
+	kfree(anand);
+	return ret;
 }
 
 static void anfc_chips_cleanup(struct arasan_nfc *nfc)
@@ -1353,8 +1373,9 @@ static void anfc_chips_cleanup(struct arasan_nfc *nfc)
 		chip = &anand->chip;
 		ret = mtd_device_unregister(nand_to_mtd(chip));
 		WARN_ON(ret);
-		nand_cleanup(chip);
+		nand_disconnect(chip);
 		list_del(&anand->node);
+		mtd_put_master(nand_to_mtd(chip));
 	}
 }
 
@@ -1431,17 +1452,24 @@ static int anfc_parse_cs(struct arasan_nfc *nfc)
 	return 0;
 }
 
+static void anfc_release(struct nand_controller *controller)
+{
+	kfree(container_of(controller, struct arasan_nfc, controller));
+}
+
 static int anfc_probe(struct platform_device *pdev)
 {
 	struct arasan_nfc *nfc;
 	int ret;
 
-	nfc = devm_kzalloc(&pdev->dev, sizeof(*nfc), GFP_KERNEL);
+	nfc = kzalloc_obj(*nfc);
 	if (!nfc)
 		return -ENOMEM;
+	ret = devm_nand_controller_init(&pdev->dev, &nfc->controller, anfc_release);
+	if (ret)
+		return ret;
 
 	nfc->dev = &pdev->dev;
-	nand_controller_init(&nfc->controller);
 	nfc->controller.ops = &anfc_ops;
 	INIT_LIST_HEAD(&nfc->chips);
 
@@ -1481,13 +1509,12 @@ static void anfc_remove(struct platform_device *pdev)
 	int i;
 	struct arasan_nfc *nfc = platform_get_drvdata(pdev);
 
+	anfc_chips_cleanup(nfc);
 	for (i = 0; i < nfc->ncs; i++) {
 		if (nfc->cs_array[i]) {
 			gpiod_put(nfc->cs_array[i]);
 		}
 	}
-
-	anfc_chips_cleanup(nfc);
 }
 
 static const struct of_device_id anfc_ids[] = {

-- 
2.53.0