[PATCH 41/58] mtd: rawnand: brcmnand: retain open-handle state on removal

[James Hilliard]

Keep chip metadata and controller storage alive until the final MTD
reference is released. Unregister and disconnect each published chip
before releasing the resources used by its hardware operations.

Unwind previously registered chip-selects on probe failure.

Signed-off-by: James Hilliard <james.hilliard1 at gmail.com>
---
 drivers/mtd/nand/raw/brcmnand/brcmnand.c | 72 +++++++++++++++++++++++---------
 1 file changed, 52 insertions(+), 20 deletions(-)

diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
index 4a1f5e736a1c..eaf0279518ca 100644
--- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
+++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
@@ -3077,6 +3077,11 @@ static const struct nand_controller_ops brcmnand_controller_ops = {
 	.exec_op = brcmnand_exec_op,
 };
 
+static void brcmnand_host_release(struct nand_chip *chip)
+{
+	kfree(container_of(chip, struct brcmnand_host, chip));
+}
+
 static int brcmnand_init_cs(struct brcmnand_host *host,
 			    const char * const *part_probe_types)
 {
@@ -3093,8 +3098,10 @@ static int brcmnand_init_cs(struct brcmnand_host *host,
 	nand_set_controller_data(chip, host);
 	mtd->name = devm_kasprintf(dev, GFP_KERNEL, "brcmnand.%d",
 				   host->cs);
-	if (!mtd->name)
-		return -ENOMEM;
+	if (!mtd->name) {
+		ret = -ENOMEM;
+		goto free_host;
+	}
 
 	mtd->owner = THIS_MODULE;
 	mtd->dev.parent = dev;
@@ -3123,12 +3130,23 @@ static int brcmnand_init_cs(struct brcmnand_host *host,
 
 	ret = nand_scan(chip, 1);
 	if (ret)
-		return ret;
+		goto free_host;
 
-	ret = mtd_device_parse_register(mtd, part_probe_types, NULL, NULL, 0);
-	if (ret)
+	ret = nand_set_release(chip, brcmnand_host_release);
+	if (ret) {
 		nand_cleanup(chip);
+		goto free_host;
+	}
+	ret = mtd_device_parse_register(mtd, part_probe_types, NULL, NULL, 0);
+	if (ret) {
+		nand_disconnect(chip);
+		mtd_put_master(mtd);
+	}
+
+	return ret;
 
+free_host:
+	kfree(host);
 	return ret;
 }
 
@@ -3294,6 +3312,26 @@ static int brcmnand_edu_setup(struct platform_device *pdev)
 	return 0;
 }
 
+static void brcmnand_chips_cleanup(struct brcmnand_controller *ctrl)
+{
+	struct brcmnand_host *host, *tmp;
+
+	list_for_each_entry_safe(host, tmp, &ctrl->host_list, node) {
+		struct nand_chip *chip = &host->chip;
+		struct mtd_info *mtd = nand_to_mtd(chip);
+
+		WARN_ON(mtd_device_unregister(mtd));
+		nand_disconnect(chip);
+		list_del(&host->node);
+		mtd_put_master(mtd);
+	}
+}
+
+static void brcmnand_release(struct nand_controller *controller)
+{
+	kfree(container_of(controller, struct brcmnand_controller, controller));
+}
+
 int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc)
 {
 	struct brcmnand_platform_data *pd = dev_get_platdata(&pdev->dev);
@@ -3307,9 +3345,12 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc)
 	if (dn && !of_match_node(brcmnand_of_match, dn))
 		return -ENODEV;
 
-	ctrl = devm_kzalloc(dev, sizeof(*ctrl), GFP_KERNEL);
+	ctrl = kzalloc_obj(*ctrl);
 	if (!ctrl)
 		return -ENOMEM;
+	ret = devm_nand_controller_init(dev, &ctrl->controller, brcmnand_release);
+	if (ret)
+		return ret;
 
 	dev_set_drvdata(dev, ctrl);
 	ctrl->dev = dev;
@@ -3324,7 +3365,6 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc)
 	init_completion(&ctrl->done);
 	init_completion(&ctrl->dma_done);
 	init_completion(&ctrl->edu_done);
-	nand_controller_init(&ctrl->controller);
 	ctrl->controller.ops = &brcmnand_controller_ops;
 	INIT_LIST_HEAD(&ctrl->host_list);
 
@@ -3489,7 +3529,7 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc)
 	for_each_available_child_of_node_scoped(dn, child) {
 		if (of_device_is_compatible(child, "brcm,nandcs")) {
 
-			host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
+			host = kzalloc_obj(*host);
 			if (!host) {
 				ret = -ENOMEM;
 				goto err;
@@ -3500,7 +3540,7 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc)
 			ret = of_property_read_u32(child, "reg", &host->cs);
 			if (ret) {
 				dev_err(dev, "can't get chip-select\n");
-				devm_kfree(dev, host);
+				kfree(host);
 				continue;
 			}
 
@@ -3511,7 +3551,6 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc)
 				if (ret == -EPROBE_DEFER)
 					goto err;
 
-				devm_kfree(dev, host);
 				continue; /* Try all chip-selects */
 			}
 
@@ -3528,7 +3567,7 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc)
 	}
 
 	/* If we got there we must have been probing via platform data */
-	host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
+	host = kzalloc_obj(*host);
 	if (!host) {
 		ret = -ENOMEM;
 		goto err;
@@ -3554,6 +3593,7 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc)
 	return 0;
 
 err:
+	brcmnand_chips_cleanup(ctrl);
 	clk_disable_unprepare(ctrl->clk);
 	return ret;
 
@@ -3563,16 +3603,8 @@ EXPORT_SYMBOL_GPL(brcmnand_probe);
 void brcmnand_remove(struct platform_device *pdev)
 {
 	struct brcmnand_controller *ctrl = dev_get_drvdata(&pdev->dev);
-	struct brcmnand_host *host;
-	struct nand_chip *chip;
-	int ret;
 
-	list_for_each_entry(host, &ctrl->host_list, node) {
-		chip = &host->chip;
-		ret = mtd_device_unregister(nand_to_mtd(chip));
-		WARN_ON(ret);
-		nand_cleanup(chip);
-	}
+	brcmnand_chips_cleanup(ctrl);
 
 	clk_disable_unprepare(ctrl->clk);
 

-- 
2.53.0