From: Michael Nazzareno Trimarchi <mich...@amarulasolutions.com> Sent: Tuesday, 19 August 2025 4:28 pm To: Maniyam, Dinesh <dinesh.mani...@altera.com> Cc: u-boot@lists.denx.de; Marek <ma...@denx.de>; Simon <simon.k.r.goldschm...@gmail.com>; Simon Glass <s...@chromium.org>; Tom Rini <tr...@konsulko.com>; Dario Binacchi <dario.binac...@amarulasolutions.com>; Chee, Tien Fong <tien.fong.c...@altera.com>; Hea, Kok Kiang <kok.kiang....@altera.com>; Ng, Boon Khai <boon.khai...@altera.com>; Yuslaimi, Alif Zakuan <alif.zakuan.yusla...@altera.com>; Lim, Jit Loon <jit.loon....@altera.com>; Dinesh Maniyam <dinesh.mani...@intel.com> Subject: Re: [PATCH v2] mtd: nand: cadence: Fix device assignment to avoid warm reset issue
[CAUTION: This email is from outside your organization. Unless you trust the sender, do not click on links or open attachments as it may be a fraudulent email attempting to steal your information and/or compromise your computer.] Hi Dinesh Please adjust your signature seems that intel.com<http://intel.com> domain is not valid Michael Hi, Submitted v3. Signature adjusted. Thanks! On Tue, Aug 19, 2025 at 10:23 AM Michael Nazzareno Trimarchi <mich...@amarulasolutions.com<mailto:mich...@amarulasolutions.com>> wrote: On Tue, Aug 19, 2025 at 9:16 AM <dinesh.mani...@altera.com<mailto:dinesh.mani...@altera.com>> wrote: From: Dinesh Maniyam <dinesh.mani...@intel.com<mailto:dinesh.mani...@intel.com>> The driver currently does: mtd->dev->parent = cadence->dev; This works in Linux because `struct mtd_info` embeds a `struct device`, so `mtd->dev` is always valid and its `.parent` can be set. In U-Boot, however, `mtd->dev` is only a pointer to a `struct udevice`. Dereferencing it before assignment is invalid, which breaks the device hierarchy. As a result, consumers relying on `mtd->dev` (e.g. partition parser, reset and re-init paths) operate on a dangling pointer. This leads to failures during warm reset when the NAND device is accessed again. Fix by assigning the device pointer directly: mtd->dev = cadence->dev; This matches U-Boot’s device model, preserves a valid hierarchy, and resolves the warm reset issue on Cadence NAND. Fixes: ebc41cad ("drivers: mtd: nand: Add driver for Cadence Nand") Signed-off-by: Dinesh Maniyam <dinesh.mani...@intel.com<mailto:dinesh.mani...@intel.com>> --- Reviewed-by: Michael Trimarchi <mich...@amarulasolutions.com<mailto:mich...@amarulasolutions.com>> drivers/mtd/nand/raw/cadence_nand.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/mtd/nand/raw/cadence_nand.c b/drivers/mtd/nand/raw/cadence_nand.c index 27aa7f97a45..4771440d1de 100644 --- a/drivers/mtd/nand/raw/cadence_nand.c +++ b/drivers/mtd/nand/raw/cadence_nand.c @@ -2196,7 +2196,7 @@ static int cadence_nand_chip_init(struct cadence_nand_info *cadence, ofnode node chip->controller = &cadence->controller; nand_set_flash_node(chip, node); mtd = nand_to_mtd(chip); - mtd->dev->parent = cadence->dev; + mtd->dev = cadence->dev; chip->options |= NAND_BUSWIDTH_AUTO; chip->select_chip = cadence_nand_select_chip; -- 2.35.3 -- Michael Nazzareno Trimarchi Co-Founder & Chief Executive Officer M. +39 347 913 2170 mich...@amarulasolutions.com<mailto:mich...@amarulasolutions.com> __________________________________ Amarula Solutions BV Joop Geesinkweg 125, 1114 AB, Amsterdam, NL T. +31 (0)85 111 9172 i...@amarulasolutions.com<mailto:i...@amarulasolutions.com> www.amarulasolutions.com<http://www.amarulasolutions.com> -- Michael Nazzareno Trimarchi Co-Founder & Chief Executive Officer M. +39 347 913 2170 mich...@amarulasolutions.com<mailto:mich...@amarulasolutions.com> __________________________________ Amarula Solutions BV Joop Geesinkweg 125, 1114 AB, Amsterdam, NL T. +31 (0)85 111 9172 i...@amarulasolutions.com<mailto:i...@amarulasolutions.com> www.amarulasolutions.com<http://www.amarulasolutions.com>
