[PATCH 42/58] mtd: rawnand: au1550nd: retain chip state across removal

[James Hilliard]

Drain NAND access before unmapping the chip-select window, and retain
the chip and controller until the final MTD reference is released. Check
MTD registration errors so unsuccessful publication releases the same
ownership.

Signed-off-by: James Hilliard <james.hilliard1 at gmail.com>
---
 drivers/mtd/nand/raw/au1550nd.c | 26 +++++++++++++++++++++-----
 1 file changed, 21 insertions(+), 5 deletions(-)

diff --git a/drivers/mtd/nand/raw/au1550nd.c b/drivers/mtd/nand/raw/au1550nd.c
index f1e99197ab84..bd78bcc84282 100644
--- a/drivers/mtd/nand/raw/au1550nd.c
+++ b/drivers/mtd/nand/raw/au1550nd.c
@@ -251,6 +251,11 @@ static const struct nand_controller_ops au1550nd_ops = {
 	.attach_chip = au1550nd_attach_chip,
 };
 
+static void au1550nd_release(struct nand_controller *controller)
+{
+	kfree(container_of(controller, struct au1550nd_ctx, controller));
+}
+
 static int au1550nd_probe(struct platform_device *pdev)
 {
 	struct au1550nd_platdata *pd;
@@ -269,6 +274,9 @@ static int au1550nd_probe(struct platform_device *pdev)
 	ctx = kzalloc_obj(*ctx);
 	if (!ctx)
 		return -ENOMEM;
+	ret = devm_nand_controller_init(&pdev->dev, &ctx->controller, au1550nd_release);
+	if (ret)
+		return ret;
 
 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!r) {
@@ -302,7 +310,6 @@ static int au1550nd_probe(struct platform_device *pdev)
 	}
 	ctx->cs = cs;
 
-	nand_controller_init(&ctx->controller);
 	ctx->controller.ops = &au1550nd_ops;
 	this->controller = &ctx->controller;
 
@@ -322,7 +329,17 @@ static int au1550nd_probe(struct platform_device *pdev)
 		goto out3;
 	}
 
-	mtd_device_register(mtd, pd->parts, pd->num_parts);
+	ret = nand_set_release(this, NULL);
+	if (ret) {
+		nand_cleanup(this);
+		goto out3;
+	}
+	ret = mtd_device_register(mtd, pd->parts, pd->num_parts);
+	if (ret) {
+		nand_disconnect(this);
+		mtd_put_master(mtd);
+		goto out3;
+	}
 
 	platform_set_drvdata(pdev, ctx);
 
@@ -333,7 +350,6 @@ static int au1550nd_probe(struct platform_device *pdev)
 out2:
 	release_mem_region(r->start, resource_size(r));
 out1:
-	kfree(ctx);
 	return ret;
 }
 
@@ -346,10 +362,10 @@ static void au1550nd_remove(struct platform_device *pdev)
 
 	ret = mtd_device_unregister(nand_to_mtd(chip));
 	WARN_ON(ret);
-	nand_cleanup(chip);
+	nand_disconnect(chip);
 	iounmap(ctx->base);
 	release_mem_region(r->start, 0x1000);
-	kfree(ctx);
+	mtd_put_master(nand_to_mtd(chip));
 }
 
 static struct platform_driver au1550nd_driver = {

-- 
2.53.0