diff options
| author | Maciej Andrzejewski <maciej.andrzejewski@m-works.net> | 2024-12-02 13:51:07 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-01-02 10:34:12 +0100 |
| commit | acb13fcf75904a016408391e57ec0646d476253f (patch) | |
| tree | d93af06e8e7c95237dc34da7e20163c9b7970021 | |
| parent | ee33d36f4174fbc58b44acb9ceca0dad1907fdeb (diff) | |
mtd: rawnand: arasan: Fix double assertion of chip-select
commit b086a46dae48829e11c0c02580e30d920b76743c upstream.
When two chip-selects are configured in the device tree, and the second is
a non-native GPIO, both the GPIO-based chip-select and the first native
chip-select may be asserted simultaneously. This double assertion causes
incorrect read and write operations.
The issue occurs because when nfc->ncs <= 2, nfc->spare_cs is always
initialized to 0 due to static initialization. Consequently, when the
second chip-select (GPIO-based) is selected in anfc_assert_cs(), it is
detected by anfc_is_gpio_cs(), and nfc->native_cs is assigned the value 0.
This results in both the GPIO-based chip-select being asserted and the
NAND controller register receiving 0, erroneously selecting the native
chip-select.
This patch resolves the issue, as confirmed by oscilloscope testing with
configurations involving two or more chip-selects in the device tree.
Fixes: acbd3d0945f9 ("mtd: rawnand: arasan: Leverage additional GPIO CS")
Cc: stable@vger.kernel.org
Signed-off-by: Maciej Andrzejewski <maciej.andrzejewski@m-works.net>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/mtd/nand/raw/arasan-nand-controller.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/mtd/nand/raw/arasan-nand-controller.c b/drivers/mtd/nand/raw/arasan-nand-controller.c index 5436ec4a8fde..7c97f421e382 100644 --- a/drivers/mtd/nand/raw/arasan-nand-controller.c +++ b/drivers/mtd/nand/raw/arasan-nand-controller.c @@ -1409,8 +1409,8 @@ static int anfc_parse_cs(struct arasan_nfc *nfc) * case, the "not" chosen CS is assigned to nfc->spare_cs and selected * whenever a GPIO CS must be asserted. */ - if (nfc->cs_array && nfc->ncs > 2) { - if (!nfc->cs_array[0] && !nfc->cs_array[1]) { + if (nfc->cs_array) { + if (nfc->ncs > 2 && !nfc->cs_array[0] && !nfc->cs_array[1]) { dev_err(nfc->dev, "Assign a single native CS when using GPIOs\n"); return -EINVAL; |