[PATCH 28/58] mtd: rawnand: loongson: retain open-handle state on removal

[James Hilliard]

Keep chip metadata and controller storage alive until the final MTD
reference is released. Unregister and disconnect each published chip
before releasing the resources used by its hardware operations.

Disconnect the chip before DMA resource cleanup.

Signed-off-by: James Hilliard <james.hilliard1 at gmail.com>
---
 drivers/mtd/nand/raw/loongson-nand-controller.c | 23 ++++++++++++++++++-----
 1 file changed, 18 insertions(+), 5 deletions(-)

diff --git a/drivers/mtd/nand/raw/loongson-nand-controller.c b/drivers/mtd/nand/raw/loongson-nand-controller.c
index 8490412d5be1..49938c7b9453 100644
--- a/drivers/mtd/nand/raw/loongson-nand-controller.c
+++ b/drivers/mtd/nand/raw/loongson-nand-controller.c
@@ -869,15 +869,26 @@ static int loongson_nand_chip_init(struct loongson_nand_host *host)
 	if (ret)
 		return dev_err_probe(dev, ret, "failed to scan NAND chip\n");
 
-	ret = mtd_device_register(mtd, NULL, 0);
+	ret = nand_set_release(chip, NULL);
 	if (ret) {
 		nand_cleanup(chip);
+		return ret;
+	}
+	ret = mtd_device_register(mtd, NULL, 0);
+	if (ret) {
+		nand_disconnect(chip);
+		mtd_put_master(mtd);
 		return dev_err_probe(dev, ret, "failed to register MTD device\n");
 	}
 
 	return 0;
 }
 
+static void loongson_nand_release(struct nand_controller *controller)
+{
+	kfree(container_of(controller, struct loongson_nand_host, controller));
+}
+
 static int loongson_nand_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -890,9 +901,12 @@ static int loongson_nand_probe(struct platform_device *pdev)
 	if (!data)
 		return -ENODEV;
 
-	host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
+	host = kzalloc_obj(*host);
 	if (!host)
 		return -ENOMEM;
+	ret = devm_nand_controller_init(dev, &host->controller, loongson_nand_release);
+	if (ret)
+		return ret;
 
 	host->reg_base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(host->reg_base))
@@ -911,8 +925,6 @@ static int loongson_nand_probe(struct platform_device *pdev)
 	host->data = data;
 	host->controller.ops = &loongson_nand_controller_ops;
 
-	nand_controller_init(&host->controller);
-
 	ret = loongson_nand_controller_init(host);
 	if (ret)
 		goto err;
@@ -938,8 +950,9 @@ static void loongson_nand_remove(struct platform_device *pdev)
 
 	ret = mtd_device_unregister(nand_to_mtd(chip));
 	WARN_ON(ret);
-	nand_cleanup(chip);
+	nand_disconnect(chip);
 	loongson_nand_controller_cleanup(host);
+	mtd_put_master(nand_to_mtd(chip));
 }
 
 static const struct loongson_nand_data ls1b_nand_data = {

-- 
2.53.0