[PATCH 44/58] mtd: rawnand: davinci: retain chip state across removal

[James Hilliard]

Disconnect the chip before releasing the shared four-bit ECC engine.
Retain the chip and controller while MTD references remain, with final
NAND cleanup independent of the device-managed hardware resources.

Signed-off-by: James Hilliard <james.hilliard1 at gmail.com>
---
 drivers/mtd/nand/raw/davinci_nand.c | 29 ++++++++++++++++++++++-------
 1 file changed, 22 insertions(+), 7 deletions(-)

diff --git a/drivers/mtd/nand/raw/davinci_nand.c b/drivers/mtd/nand/raw/davinci_nand.c
index 3986553881d0..2231e6a45114 100644
--- a/drivers/mtd/nand/raw/davinci_nand.c
+++ b/drivers/mtd/nand/raw/davinci_nand.c
@@ -895,6 +895,11 @@ static const struct nand_controller_ops davinci_nand_controller_ops = {
 	.setup_interface = davinci_nand_setup_interface,
 };
 
+static void nand_davinci_release(struct nand_controller *controller)
+{
+	kfree(container_of(controller, struct davinci_nand_info, controller));
+}
+
 static int nand_davinci_probe(struct platform_device *pdev)
 {
 	struct davinci_nand_pdata	*pdata;
@@ -919,9 +924,12 @@ static int nand_davinci_probe(struct platform_device *pdev)
 	if (pdata->core_chipsel > 3)
 		return -ENODEV;
 
-	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
+	info = kzalloc_obj(*info);
 	if (!info)
 		return -ENOMEM;
+	ret = devm_nand_controller_init(&pdev->dev, &info->controller, nand_davinci_release);
+	if (ret)
+		return ret;
 
 	platform_set_drvdata(pdev, info);
 
@@ -986,7 +994,6 @@ static int nand_davinci_probe(struct platform_device *pdev)
 	spin_unlock_irq(&davinci_nand_lock);
 
 	/* Scan to find existence of the device(s) */
-	nand_controller_init(&info->controller);
 	info->controller.ops = &davinci_nand_controller_ops;
 	info->chip.controller = &info->controller;
 	ret = nand_scan(&info->chip, pdata->mask_chipsel ? 2 : 1);
@@ -995,12 +1002,18 @@ static int nand_davinci_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	ret = nand_set_release(&info->chip, NULL);
+	if (ret)
+		goto err_cleanup_nand;
 	if (pdata->parts)
 		ret = mtd_device_register(mtd, pdata->parts, pdata->nr_parts);
 	else
 		ret = mtd_device_register(mtd, NULL, 0);
-	if (ret < 0)
-		goto err_cleanup_nand;
+	if (ret < 0) {
+		nand_disconnect(&info->chip);
+		mtd_put_master(mtd);
+		return ret;
+	}
 
 	val = davinci_nand_readl(info, NRCSR_OFFSET);
 	dev_info(&pdev->dev, "controller rev. %d.%d\n",
@@ -1020,14 +1033,16 @@ static void nand_davinci_remove(struct platform_device *pdev)
 	struct nand_chip *chip = &info->chip;
 	int ret;
 
+	ret = mtd_device_unregister(nand_to_mtd(chip));
+	WARN_ON(ret);
+	nand_disconnect(chip);
+
 	spin_lock_irq(&davinci_nand_lock);
 	if (chip->ecc.placement == NAND_ECC_PLACEMENT_INTERLEAVED)
 		ecc4_busy = false;
 	spin_unlock_irq(&davinci_nand_lock);
 
-	ret = mtd_device_unregister(nand_to_mtd(chip));
-	WARN_ON(ret);
-	nand_cleanup(chip);
+	mtd_put_master(nand_to_mtd(chip));
 }
 
 static struct platform_driver nand_davinci_driver = {

-- 
2.53.0