[PATCH 14/58] mtd: rawnand: intel: retain open-handle state on removal

[James Hilliard]

Disconnect NAND operations after unregistering MTD and before disabling
the controller or releasing DMA channels. Retain the embedded chip,
controller lock and NAND metadata until the last MTD reference is
released, including references obtained during a partially successful
probe.

Fixes: 0b1039f016e8 ("mtd: rawnand: Add NAND controller support on Intel LGM SoC")
Signed-off-by: James Hilliard <james.hilliard1 at gmail.com>
---
 drivers/mtd/nand/raw/intel-nand-controller.c | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/drivers/mtd/nand/raw/intel-nand-controller.c b/drivers/mtd/nand/raw/intel-nand-controller.c
index 477a427dac1f..e4a24e69ebbc 100644
--- a/drivers/mtd/nand/raw/intel-nand-controller.c
+++ b/drivers/mtd/nand/raw/intel-nand-controller.c
@@ -573,6 +573,11 @@ static void ebu_dma_cleanup(struct ebu_nand_controller *ebu_host)
 		dma_release_channel(ebu_host->dma_tx);
 }
 
+static void ebu_nand_release(struct nand_controller *controller)
+{
+	kfree(container_of(controller, struct ebu_nand_controller, controller));
+}
+
 static int ebu_nand_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -585,12 +590,14 @@ static int ebu_nand_probe(struct platform_device *pdev)
 	int ret;
 	u32 cs;
 
-	ebu_host = devm_kzalloc(dev, sizeof(*ebu_host), GFP_KERNEL);
+	ebu_host = kzalloc_obj(*ebu_host);
 	if (!ebu_host)
 		return -ENOMEM;
+	ret = devm_nand_controller_init(dev, &ebu_host->controller, ebu_nand_release);
+	if (ret)
+		return ret;
 
 	ebu_host->dev = dev;
-	nand_controller_init(&ebu_host->controller);
 
 	ebu_host->ebu = devm_platform_ioremap_resource_byname(pdev, "ebunand");
 	if (IS_ERR(ebu_host->ebu))
@@ -692,9 +699,15 @@ static int ebu_nand_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_cleanup_dma;
 
-	ret = mtd_device_register(mtd, NULL, 0);
+	ret = nand_set_release(nand, NULL);
 	if (ret)
 		goto err_clean_nand;
+	ret = mtd_device_register(mtd, NULL, 0);
+	if (ret) {
+		nand_disconnect(nand);
+		mtd_put_master(mtd);
+		goto err_cleanup_dma;
+	}
 
 	return 0;
 
@@ -715,9 +728,10 @@ static void ebu_nand_remove(struct platform_device *pdev)
 
 	ret = mtd_device_unregister(nand_to_mtd(&ebu_host->chip));
 	WARN_ON(ret);
-	nand_cleanup(&ebu_host->chip);
+	nand_disconnect(&ebu_host->chip);
 	ebu_nand_disable(&ebu_host->chip);
 	ebu_dma_cleanup(ebu_host);
+	mtd_put_master(nand_to_mtd(&ebu_host->chip));
 }
 
 static const struct of_device_id ebu_nand_match[] = {

-- 
2.53.0