mtd: spi-nor: sysfs: print JEDEC ID for generic flash driver

We don't have a database entry for the generic SPI-NOR flash driver and
thus we don't have a JEDEC ID to print. Print the (cached) JEDEC ID
instead.
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
Link: https://lore.kernel.org/r/20220810220654.1297699-8-michael@walle.cc

drivers/mtd/spi-nor/sysfs.c

@@ -35,8 +35,10 @@ static ssize_t jedec_id_show(struct device *dev,
 	struct spi_device *spi = to_spi_device(dev);
 	struct spi_mem *spimem = spi_get_drvdata(spi);
 	struct spi_nor *nor = spi_mem_get_drvdata(spimem);
+	const u8 *id = nor->info->id_len ? nor->info->id : nor->id;
+	u8 id_len = nor->info->id_len ?: SPI_NOR_MAX_ID_LEN;
 
-	return sysfs_emit(buf, "%*phN\n", nor->info->id_len, nor->info->id);
+	return sysfs_emit(buf, "%*phN\n", id_len, id);
 }
 static DEVICE_ATTR_RO(jedec_id);
 
@@ -76,7 +78,7 @@ static umode_t spi_nor_sysfs_is_visible(struct kobject *kobj,
 
 	if (attr == &dev_attr_manufacturer.attr && !nor->manufacturer)
 		return 0;
-	if (attr == &dev_attr_jedec_id.attr && !nor->info->id_len)
+	if (attr == &dev_attr_jedec_id.attr && !nor->info->id_len && !nor->id)
 		return 0;
 
 	return 0444;