[PATCH v4 51/58] mtd: rawnand: mpc5121: retain chip state across removal

[James Hilliard]

Drain NAND access before unmapping the external chip-select registers.
Keep the embedded chip and controller alive until the final MTD
reference, and unwind scanned NAND state on unsupported geometry and
publication failure.

Run NAND cleanup during disconnection; the final core-owned put only
releases retained allocation and layout data.

Fixes: bb315f749f8c ("mtd: nand: Add MPC5121 NAND Flash Controller driver")
Signed-off-by: James Hilliard <james.hilliard1@xxxxxxxxx>
---
 drivers/mtd/nand/raw/mpc5121_nfc.c | 24 +++++++++++++++++-------
 1 file changed, 17 insertions(+), 7 deletions(-)

diff --git a/drivers/mtd/nand/raw/mpc5121_nfc.c b/drivers/mtd/nand/raw/mpc5121_nfc.c
index 0aeeb6327472..42e167e1db7e 100644
--- a/drivers/mtd/nand/raw/mpc5121_nfc.c
+++ b/drivers/mtd/nand/raw/mpc5121_nfc.c
@@ -636,6 +636,13 @@ static int mpc5121_nfc_probe(struct platform_device *op)
 		return -ENXIO;
 	}
 
+	prv = kzalloc_obj(*prv);
+	if (!prv)
+		return -ENOMEM;
+	retval = devm_nand_controller_init(dev, &prv->controller, prv);
+	if (retval)
+		return retval;
+
 	regs = devm_platform_ioremap_resource(op, 0);
 	if (IS_ERR(regs))
 		return PTR_ERR(regs);
@@ -644,14 +651,9 @@ static int mpc5121_nfc_probe(struct platform_device *op)
 	if (irq < 0)
 		return irq;
 
-	prv = devm_kzalloc(dev, sizeof(*prv), GFP_KERNEL);
-	if (!prv)
-		return -ENOMEM;
-
 	chip = &prv->chip;
 	mtd = nand_to_mtd(chip);
 
-	nand_controller_init(&prv->controller);
 	prv->controller.ops = &mpc5121_nfc_ops;
 	chip->controller = &prv->controller;
 
@@ -782,19 +784,26 @@ static int mpc5121_nfc_probe(struct platform_device *op)
 	default:
 		dev_err(dev, "Unsupported NAND flash!\n");
 		retval = -ENXIO;
-		goto error;
+		goto cleanup_nand;
 	}
 
 	dev_set_drvdata(dev, mtd);
 
 	/* Register device in MTD */
+	retval = nand_set_lifetime(chip, NULL);
+	if (retval)
+		goto cleanup_nand;
 	retval = mtd_device_register(mtd, NULL, 0);
 	if (retval) {
 		dev_err(dev, "Error adding MTD device!\n");
+		nand_disconnect(chip);
+		mtd_put_master(mtd);
 		goto error;
 	}
 
 	return 0;
+cleanup_nand:
+	nand_cleanup(chip);
 error:
 	mpc5121_nfc_free(dev, mtd);
 	return retval;
@@ -808,8 +817,9 @@ static void mpc5121_nfc_remove(struct platform_device *op)
 
 	ret = mtd_device_unregister(mtd);
 	WARN_ON(ret);
-	nand_cleanup(mtd_to_nand(mtd));
+	nand_disconnect(mtd_to_nand(mtd));
 	mpc5121_nfc_free(dev, mtd);
+	mtd_put_master(mtd);
 }
 
 static const struct of_device_id mpc5121_nfc_match[] = {

-- 
2.53.0