[PATCH 46/58] mtd: rawnand: lpc32xx_slc: retain chip state across removal

[James Hilliard]

Drain chip operations before releasing DMA and changing the controller
and write-protect signals. Retain the embedded NAND chip and controller
until the final MTD reference releases their metadata.

Signed-off-by: James Hilliard <james.hilliard1 at gmail.com>
---
 drivers/mtd/nand/raw/lpc32xx_slc.c | 26 ++++++++++++++++++++++----
 1 file changed, 22 insertions(+), 4 deletions(-)

diff --git a/drivers/mtd/nand/raw/lpc32xx_slc.c b/drivers/mtd/nand/raw/lpc32xx_slc.c
index b4d90afa9267..85945e1dd25a 100644
--- a/drivers/mtd/nand/raw/lpc32xx_slc.c
+++ b/drivers/mtd/nand/raw/lpc32xx_slc.c
@@ -817,6 +817,12 @@ static const struct nand_controller_ops lpc32xx_nand_controller_ops = {
 	.attach_chip = lpc32xx_nand_attach_chip,
 };
 
+static void lpc32xx_nand_release(struct nand_controller *controller)
+{
+	kfree(container_of(controller, struct lpc32xx_nand_host,
+			   nand_chip.legacy.dummy_controller));
+}
+
 /*
  * Probe for NAND controller
  */
@@ -829,9 +835,14 @@ static int lpc32xx_nand_probe(struct platform_device *pdev)
 	int res;
 
 	/* Allocate memory for the device structure (and zero it) */
-	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
+	host = kzalloc_obj(*host);
 	if (!host)
 		return -ENOMEM;
+	chip = &host->nand_chip;
+	chip->controller = &chip->legacy.dummy_controller;
+	res = devm_nand_controller_init(&pdev->dev, chip->controller, lpc32xx_nand_release);
+	if (res)
+		return res;
 
 	host->io_base = devm_platform_get_and_ioremap_resource(pdev, 0, &rc);
 	if (IS_ERR(host->io_base))
@@ -915,10 +926,16 @@ static int lpc32xx_nand_probe(struct platform_device *pdev)
 		goto release_dma;
 
 	mtd->name = "nxp_lpc3220_slc";
-	res = mtd_device_register(mtd, host->ncfg->parts,
-				  host->ncfg->num_parts);
+	res = nand_set_release(chip, NULL);
 	if (res)
 		goto cleanup_nand;
+	res = mtd_device_register(mtd, host->ncfg->parts,
+				  host->ncfg->num_parts);
+	if (res) {
+		nand_disconnect(chip);
+		mtd_put_master(mtd);
+		goto release_dma;
+	}
 
 	return 0;
 
@@ -944,7 +961,7 @@ static void lpc32xx_nand_remove(struct platform_device *pdev)
 
 	ret = mtd_device_unregister(nand_to_mtd(chip));
 	WARN_ON(ret);
-	nand_cleanup(chip);
+	nand_disconnect(chip);
 	dma_release_channel(host->dma_chan);
 
 	/* Force CE high */
@@ -953,6 +970,7 @@ static void lpc32xx_nand_remove(struct platform_device *pdev)
 	writel(tmp, SLC_CTRL(host->io_base));
 
 	lpc32xx_wp_enable(host);
+	mtd_put_master(nand_to_mtd(chip));
 }
 
 static int lpc32xx_nand_resume(struct platform_device *pdev)

-- 
2.53.0