[PATCH] mtd: core: clear out unregistered devices a bit more

[PATCH] mtd: core: clear out unregistered devices a bit more

[Zev Weiss]

This allows an MTD device that has been unregistered to be easily
re-registered later without triggering spurious "already registered"
warnings in mtd_device_parse_register() and add_mtd_device().

Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
---
 drivers/mtd/mtdcore.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index 153229198947..0a0fca737d43 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -747,6 +747,9 @@ int del_mtd_device(struct mtd_info *mtd)
 
 		device_unregister(&mtd->dev);
 
+		/* Clear dev so mtd can be safely re-registered later if desired */
+		memset(&mtd->dev, 0, sizeof(mtd->dev));
+
 		idr_remove(&mtd_idr, mtd->index);
 		of_node_put(mtd_get_of_node(mtd));
 
@@ -1018,8 +1021,10 @@ int mtd_device_unregister(struct mtd_info *master)
 {
 	int err;
 
-	if (master->_reboot)
+	if (master->_reboot) {
 		unregister_reboot_notifier(&master->reboot_notifier);
+		memset(&master->reboot_notifier, 0, sizeof(master->reboot_notifier));
+	}
 
 	if (master->otp_user_nvmem)
 		nvmem_unregister(master->otp_user_nvmem);
-- 
2.33.0

Re: [PATCH] mtd: core: clear out unregistered devices a bit more

[Miquel Raynal]

On Fri, 2021-10-15 at 18:50:48 UTC, Zev Weiss wrote:
> This allows an MTD device that has been unregistered to be easily
> re-registered later without triggering spurious "already registered"
> warnings in mtd_device_parse_register() and add_mtd_device().
> 
> Signed-off-by: Zev Weiss <zev@bewilderbeest.net>

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git mtd/next, thanks.

Miquel