mtd: Fix misuses of of_match_ptr()

of_match_ptr() either expands to NULL if !CONFIG_OF, or is transparent
otherwise. There are several drivers using this macro which keep their
of_device_id array enclosed within an #ifdef CONFIG_OF check, these are
considered fine. However, When misused, the of_device_id array pointed
by this macro will produce a warning because it is finally unused when
compiled without OF support.

A number of fixes are possible:
- Always depend on CONFIG_OF, but this will not always work and may
  break boards.
- Enclose the compatible array by #ifdef's, this may save a bit of
  memory but will reduce build coverage.
- Tell the compiler the array may be unused, if this can be avoided,
  let's not do this.
- Just drop the macro, setting the of_device_id array for a non OF
  enabled platform is not an issue, it will just be unused.

The latter solution seems the more appropriate, so let's use it.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/linux-mtd/20220127110631.1064705-1-miquel.raynal@bootlin.com

2 files changed, 2 insertions, 2 deletions

diff --git a/drivers/mtd/nand/raw/ingenic/ingenic_nand_drv.c b/drivers/mtd/nand/raw/ingenic/ingenic_nand_drv.c
index b18861bdcdc8..ff26c10f295d 100644
--- a/drivers/mtd/nand/raw/ingenic/ingenic_nand_drv.c
+++ b/drivers/mtd/nand/raw/ingenic/ingenic_nand_drv.c
@@ -567,7 +567,7 @@ static struct platform_driver ingenic_nand_driver = {
 	.remove		= ingenic_nand_remove,
 	.driver	= {
 		.name	= DRV_NAME,
-		.of_match_table = of_match_ptr(ingenic_nand_dt_match),
+		.of_match_table = ingenic_nand_dt_match,
 	},
 };
 module_platform_driver(ingenic_nand_driver);
diff --git a/drivers/mtd/nand/raw/ingenic/jz4780_bch.c b/drivers/mtd/nand/raw/ingenic/jz4780_bch.c
index d67dbfff76cc..12b5b0484fe9 100644
--- a/drivers/mtd/nand/raw/ingenic/jz4780_bch.c
+++ b/drivers/mtd/nand/raw/ingenic/jz4780_bch.c
@@ -260,7 +260,7 @@ static struct platform_driver jz4780_bch_driver = {
 	.probe		= jz4780_bch_probe,
 	.driver	= {
 		.name	= "jz4780-bch",
-		.of_match_table = of_match_ptr(jz4780_bch_dt_match),
+		.of_match_table = jz4780_bch_dt_match,
 	},
 };
 module_platform_driver(jz4780_bch_driver);