mtd: rawnand: atmel: Defer probe if SRAM is missing

The Atmel NAND controller driver depends on an SRAM pool and has an
implicit assumption that the SRAM pool has already been created.
Changing the initcall ordering can break this. Unfortunately, fw_devlink
can't save us here as there's not a standard property to track the
dependency. So it's up to deferring probe to save us.

Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Tested-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

diff --git a/drivers/mtd/nand/raw/atmel/nand-controller.c b/drivers/mtd/nand/raw/atmel/nand-controller.c
index 83ba4eb..e7fdf53 100644 (file)
--- a/drivers/mtd/nand/raw/atmel/nand-controller.c
+++ b/drivers/mtd/nand/raw/atmel/nand-controller.c
@@ -2304,10 +2304,8 @@ atmel_hsmc_nand_controller_init(struct atmel_hsmc_nand_controller *nc)
 
        nc->sram.pool = of_gen_pool_get(nc->base.dev->of_node,
                                         "atmel,nfc-sram", 0);
-       if (!nc->sram.pool) {
-               dev_err(nc->base.dev, "Missing SRAM\n");
-               return -ENOMEM;
-       }
+       if (!nc->sram.pool)
+               return dev_err_probe(nc->base.dev, -EPROBE_DEFER, "Missing SRAM\n");
 
        nc->sram.virt = (void __iomem *)gen_pool_dma_alloc(nc->sram.pool,
                                                           ATMEL_NFC_SRAM_SIZE,