From: Michael Walle <michael@xxxxxxxx> [ Upstream commit 7d388551b6888f3725e6c957f472526b35161a5b ] Some non-jedec compliant flashes (like the Everspin flashes) don't have an ID at all. Hide the attribute in this case. Fixes: 36ac02286265 ("mtd: spi-nor: add initial sysfs support") Signed-off-by: Michael Walle <michael@xxxxxxxx> Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx> Reviewed-by: Takahiro Kuwano <Takahiro.Kuwano@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20220810220654.1297699-2-michael@xxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- .../ABI/testing/sysfs-bus-spi-devices-spi-nor | 3 +++ drivers/mtd/spi-nor/sysfs.c | 14 ++++++++++++++ 2 files changed, 17 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-spi-devices-spi-nor b/Documentation/ABI/testing/sysfs-bus-spi-devices-spi-nor index d76cd3946434..e9ef69aef20b 100644 --- a/Documentation/ABI/testing/sysfs-bus-spi-devices-spi-nor +++ b/Documentation/ABI/testing/sysfs-bus-spi-devices-spi-nor @@ -5,6 +5,9 @@ Contact: linux-mtd@xxxxxxxxxxxxxxxxxxx Description: (RO) The JEDEC ID of the SPI NOR flash as reported by the flash device. + The attribute is not present if the flash doesn't support + the "Read JEDEC ID" command (9Fh). This is the case for + non-JEDEC compliant flashes. What: /sys/bus/spi/devices/.../spi-nor/manufacturer Date: April 2021 diff --git a/drivers/mtd/spi-nor/sysfs.c b/drivers/mtd/spi-nor/sysfs.c index 9aec9d8a98ad..4c3b351aef24 100644 --- a/drivers/mtd/spi-nor/sysfs.c +++ b/drivers/mtd/spi-nor/sysfs.c @@ -67,6 +67,19 @@ static struct bin_attribute *spi_nor_sysfs_bin_entries[] = { NULL }; +static umode_t spi_nor_sysfs_is_visible(struct kobject *kobj, + struct attribute *attr, int n) +{ + struct spi_device *spi = to_spi_device(kobj_to_dev(kobj)); + struct spi_mem *spimem = spi_get_drvdata(spi); + struct spi_nor *nor = spi_mem_get_drvdata(spimem); + + if (attr == &dev_attr_jedec_id.attr && !nor->info->id_len) + return 0; + + return 0444; +} + static umode_t spi_nor_sysfs_is_bin_visible(struct kobject *kobj, struct bin_attribute *attr, int n) { @@ -82,6 +95,7 @@ static umode_t spi_nor_sysfs_is_bin_visible(struct kobject *kobj, static const struct attribute_group spi_nor_sysfs_group = { .name = "spi-nor", + .is_visible = spi_nor_sysfs_is_visible, .is_bin_visible = spi_nor_sysfs_is_bin_visible, .attrs = spi_nor_sysfs_entries, .bin_attrs = spi_nor_sysfs_bin_entries, -- 2.35.1