From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=68.232.153.233 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794398503; b=2EjwgNjZo6bF4Lm9LLcc02ZWbsFN9h2AhZ4QTGhFdNX4e1IEykGb30t0KS1SJultOh7R f09w4bSF15CGJMpcTnzR6sORKo0ibFNapXKhKEqiO5vInmznNjsTx6G8mD1UNoOi3Z+ck dLRSSDNK9ub1RQ5OfcdgynqDBzCviw+jGf7feVNwRQS7+CJIcfokaThN4yPlyO4ToCnUc toTrcXrkXhAlxnyfnEnWearhklSXwERtOjb+h9h1jImhE32+Sv1LiT0FNilQW2kC9JTCl oQ6Gtwx+LkETHPGj9rxNrXKPB5wHqoVnCqxraVUjXkVFhD+nCCL3Fm1Ig2C0bgL/76A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794398503; h=DMARC-Filter:DKIM-Signature:X-CSE-ConnectionGUID:X-CSE-MsgGUID: X-IronPort-AV:X-Amp-Result:Received:Received:Received:From:To:CC: Subject:Date:Message-ID:X-Mailer:MIME-Version: Content-Transfer-Encoding:Content-Type; bh=KlktvsLZYoPwubEiMpTIlxQcLIKK3gDMoHZIsK9MbTY=; b=gN19sti0DMsl1nZ+DCWPcWGt2FBiM+jsXb2BOWWPXordq6yoFFIM5DNJoHnXJ80OTmoB 281nDouPPYo7MoZJ6b11kOIKJ+99dzx89yumIHRbaqSkxXbETeL3AY8sL0Tl7TqaM+Oz1 Od6br88eq9rWBCcYewk9NaZQChUhHgLhxMo/547QdsHXbwl8Tp5/yzrU0KWw/oxCUh6F/ 4J0IM1lHJJUPbG5aNlk3GiPJmp31MEjWiCLv1ollJiL3+HC8lXZDAGdRFk9soPt1nkT0F PjmWMIZB0fTLkL7MF5+9pYm5yHy6FHndt91V+7MQgzpKnyHk+1LjVPDtimdvyv2SLPA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=microchip.com; spf=pass smtp.mailfrom=microchip.com; dkim=pass header.d=microchip.com header.i=@microchip.com header.a=rsa-sha256 header.s=mchp header.b=MRJ4P4rn; arc=none smtp.remote-ip=68.232.153.233 Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.153.233]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2B1B7606A335 for ; Wed, 11 Nov 2026 12:01:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 2B1B7606A335 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=microchip.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=microchip.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=microchip.com header.i=@microchip.com header.a=rsa-sha256 header.s=mchp header.b=MRJ4P4rn DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1794398504; x=1825934504; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=BgXJlhRxC+Hv4DPLB3wg8Xh8XMZb+jo7t7rlEKPdX4I=; b=MRJ4P4rnsgIFda1/1XSv8XByrCJGEZtOudx8TanMDbcDw2rdCW3KGn5j POMxJ4hOOP9sBA5rakACFUTgwS6zTRF430oM8N+FieZB/OPdB0swl5qb9 UL63tAJ5+pQ8CQhBj2i6QNsVWvWOd1YsnPnXVH/uijSbVQZDFMyRk/1D1 D5rDiWK39keM7EH3NiHed3Uy54NFRG5vBI1bIzdsr5mB83qRbNn0OsbqU M6NtercFox9FQbZXZCuaZi5x+Rg2v1f/yjPp8oa9LiNUv/QrBgDlhcCwH DmkC1wIMzk5BS53+KimlvuwAhfhmsSeoJn1QCWMvaipYmywumM8byTKSe A==; X-CSE-ConnectionGUID: u70z195URju4bTRXoeI/AQ== X-CSE-MsgGUID: UrpMuQ2/QZq5Oon+eWC9sw== X-IronPort-AV: E=Sophos;i="6.27,207,1787036400"; d="scan'208";a="297769589" X-Amp-Result: SKIPPED(no attachment in message) Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa5.microchip.iphmx.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 11 Nov 2026 05:01:43 -0700 Received: from chn-vm-ex03.mchp-main.com (10.10.85.151) by chn-vm-ex03.mchp-main.com (10.10.85.151) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.58; Wed, 11 Nov 2026 05:01:41 -0700 Received: from che-ll-i67131.microchip.com (10.10.85.11) by chn-vm-ex03.mchp-main.com (10.10.85.151) with Microsoft SMTP Server id 15.1.2507.58 via Frontend Transport; Wed, 11 Nov 2026 05:01:38 -0700 From: Manikandan Muralidharan To: , , , , , , , , CC: Subject: [PATCH 0/2] mtd/nvmem: don't defer forever on absent NVMEM suppliers Date: Wed, 11 Nov 2026 17:31:30 +0530 Message-ID: X-Mailer: git-send-email 2.43.0 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain A consumer that gets its MAC address from an NVMEM cell can be deferred forever when the cell will never appear, instead of falling back to another address source. These came up while testing the SFDP EUI-48 series [1], where macb reads its MAC address from a cell exposed by the QSPI flash, but both are generic: - 1/2: when the SPI NOR flash is not populated or not reachable, nothing below its node is ever registered, yet fw_devlink keeps waiting on it and the NVMEM lookup keeps returning -EPROBE_DEFER. Drop the fw_devlink links below a flash that failed to probe, and return -ENOENT for a cell on a node fw_devlink has marked as never becoming a device. - 2/2: a layout adds its cells from its probe and may add none, e.g. when the data the cell describes is not programmed on the device. Only defer while the layout is not bound yet, and return -ENOENT once it is. In both cases the consumer then falls back, e.g. macb uses the address left by the bootloader or a random one. This series depends on the SFDP EUI-48 series [1] and applies on top of it. [1] https://lore.kernel.org/all/cover.1794391660.git.manikandan.m@microchip.com/ Manikandan Muralidharan (2): mtd: spi-nor: drop fw_devlink suppliers below a flash that failed to probe nvmem: core: don't defer for a missing cell once the layout is bound drivers/mtd/spi-nor/core.c | 26 ++++++++++++++++++++++++- drivers/nvmem/core.c | 40 ++++++++++++++++++++++++++++++++++++-- 2 files changed, 63 insertions(+), 3 deletions(-) base-commit: 05441d697f7f9a927264f4058cbbc6a03dfcac9d prerequisite-patch-id: 76d8b1168f88c3e7912ac2ce01a705f7e69d8a3b prerequisite-patch-id: b360d0d00ac1a6feb76d4b3f9412b6f1741f6161 prerequisite-patch-id: 659801d6f415ba79ce51f21b3a4f5e132348c150 prerequisite-patch-id: bd1a5a10983aa3cfd99c93ee58fdeb04cdd87b76 prerequisite-patch-id: 94ede38b6c2480cb1e0e102e9bbeb6ffd5b276ef prerequisite-patch-id: ae3977b6c56c5bd4f352d77bd8a7883a69d390af prerequisite-patch-id: 58d0ad25e81f16f60864d624eed7ff481607e960 prerequisite-patch-id: ba140b71fdbfc992861ae4c34b6acc737d4e4528 -- 2.43.0