[PATCH 48/58] mtd: rawnand: ndfc: retain chip state across removal

[James Hilliard]

Allocate controller state per binding instead of reusing the static
chip-select slots. A retained MTD handle must keep its original chip
state when the platform device is rebound. Disconnect the old chip
before device resources disappear and release its state at the final MTD
put.

Signed-off-by: James Hilliard <james.hilliard1 at gmail.com>
---
 drivers/mtd/nand/raw/ndfc.c | 37 +++++++++++++++++++++++++++----------
 1 file changed, 27 insertions(+), 10 deletions(-)

diff --git a/drivers/mtd/nand/raw/ndfc.c b/drivers/mtd/nand/raw/ndfc.c
index d7b119028a71..50506ad87fd4 100644
--- a/drivers/mtd/nand/raw/ndfc.c
+++ b/drivers/mtd/nand/raw/ndfc.c
@@ -37,8 +37,6 @@ struct ndfc_controller {
 	struct nand_controller ndfc_control;
 };
 
-static struct ndfc_controller ndfc_ctrl[NDFC_MAX_CS];
-
 static void ndfc_select_chip(struct nand_chip *nchip, int chip)
 {
 	uint32_t ccr;
@@ -173,13 +171,27 @@ static int ndfc_chip_init(struct ndfc_controller *ndfc,
 	if (ret)
 		goto err;
 
+	ret = nand_set_release(chip, NULL);
+	if (ret) {
+		nand_cleanup(chip);
+		goto err;
+	}
 	ret = mtd_device_register(mtd, NULL, 0);
+	if (ret) {
+		nand_disconnect(chip);
+		mtd_put_master(mtd);
+	}
 
 err:
 	of_node_put(flash_np);
 	return ret;
 }
 
+static void ndfc_release(struct nand_controller *controller)
+{
+	kfree(container_of(controller, struct ndfc_controller, ndfc_control));
+}
+
 static int ndfc_probe(struct platform_device *ofdev)
 {
 	struct ndfc_controller *ndfc;
@@ -187,11 +199,7 @@ static int ndfc_probe(struct platform_device *ofdev)
 	const __be32 *reg;
 	u32 ccr;
 	u32 cs;
-	int len = 0;
-
-	ndfcbase = devm_platform_ioremap_resource(ofdev, 0);
-	if (IS_ERR(ndfcbase))
-		return PTR_ERR(ndfcbase);
+	int len = 0, ret;
 
 	/* Read the reg property to get the chip select */
 	reg = of_get_property(ofdev->dev.of_node, "reg", &len);
@@ -206,10 +214,18 @@ static int ndfc_probe(struct platform_device *ofdev)
 		return -EINVAL;
 	}
 
-	ndfc = &ndfc_ctrl[cs];
+	ndfc = kzalloc_obj(*ndfc);
+	if (!ndfc)
+		return -ENOMEM;
+	ret = devm_nand_controller_init(&ofdev->dev, &ndfc->ndfc_control, ndfc_release);
+	if (ret)
+		return ret;
+
+	ndfcbase = devm_platform_ioremap_resource(ofdev, 0);
+	if (IS_ERR(ndfcbase))
+		return PTR_ERR(ndfcbase);
 	ndfc->chip_select = cs;
 
-	nand_controller_init(&ndfc->ndfc_control);
 	ndfc->ofdev = ofdev;
 	dev_set_drvdata(&ofdev->dev, ndfc);
 
@@ -243,7 +259,8 @@ static void ndfc_remove(struct platform_device *ofdev)
 
 	ret = mtd_device_unregister(mtd);
 	WARN_ON(ret);
-	nand_cleanup(chip);
+	nand_disconnect(chip);
+	mtd_put_master(mtd);
 }
 
 static const struct of_device_id ndfc_match[] = {

-- 
2.53.0