From:   Miquel Raynal <miquel.raynal@bootlin.com>
To:     Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
        <linux-kernel@vger.kernel.org>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Michael Walle <michael@walle.cc>,
        =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>,
        Robert Marko <robert.marko@sartura.hr>,
        Luka Perkov <luka.perkov@sartura.hr>,
        Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
        Rob Herring <robh+dt@kernel.org>,
        Frank Rowand <frowand.list@gmail.com>,
        devicetree@vger.kernel.org,
        Alexander Stein <alexander.stein@ew.tq-group.com>,
        Miquel Raynal <miquel.raynal@bootlin.com>
Subject: [PATCH v2 09/21] nvmem: core: return -ENOENT if nvmem cell is not found
Date:   Tue,  7 Mar 2023 17:53:47 +0100
Message-Id: <20230307165359.225361-10-miquel.raynal@bootlin.com>
In-Reply-To: <20230307165359.225361-1-miquel.raynal@bootlin.com>
References: <20230307165359.225361-1-miquel.raynal@bootlin.com>
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From: Michael Walle <michael@walle.cc>

Prior to commit 3cb05fdbaed6 ("nvmem: core: add an index parameter to
the cell") of_nvmem_cell_get() would return -ENOENT if the cell wasn't
found. Particularly, if of_property_match_string() returned -EINVAL,
that return code was passed as the index to of_parse_phandle(), which
then detected it as invalid and returned NULL. That led to an return
code of -ENOENT.

With the new code, the negative index will lead to an -EINVAL of
of_parse_phandle_with_optional_args() which pass straight to the
caller and break those who expect an -ENOENT.

Fix it by always returning -ENOENT.

Fixes: efff2655ab0f ("nvmem: core: add an index parameter to the cell")
Reported-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/nvmem/core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index 174ef3574e07..22024b830788 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -1231,7 +1231,7 @@ struct nvmem_cell *of_nvmem_cell_get(struct device_node *np, const char *id)
 						  "#nvmem-cell-cells",
 						  index, &cell_spec);
 	if (ret)
-		return ERR_PTR(ret);
+		return ERR_PTR(-ENOENT);
 
 	if (cell_spec.args_count > 1)
 		return ERR_PTR(-EINVAL);
-- 
2.34.1