mtd: rawnand: brcmnand: skip DMA during panic write

[ Upstream commit da9ba4d ]

When oops_panic_write is set, the driver disables interrupts and
switches to PIO polling mode but still falls through into the DMA
path. DMA cannot be used reliably in panic context, so make the
DMA path an else branch to ensure only PIO is used during panic
writes.

Fixes: c1ac2dc ("mtd: rawnand: brcmnand: When oops in progress use pio and interrupt polling")
Signed-off-by: Kamal Dasu <kamal.dasu@broadcom.com>
Reviewed-by: William Zhang <william.zhang@broadcom.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: kamaldasu-crypto

drivers/mtd/nand/raw/brcmnand/brcmnand.c

@@ -2303,14 +2303,12 @@ static int brcmnand_write(struct mtd_info *mtd, struct nand_chip *chip,
 	for (i = 0; i < ctrl->max_oob; i += 4)
 		oob_reg_write(ctrl, i, 0xffffffff);
 
-	if (mtd->oops_panic_write)
+	if (mtd->oops_panic_write) {
 		/* switch to interrupt polling and PIO mode */
 		disable_ctrl_irqs(ctrl);
-
-	if (use_dma(ctrl) && (has_edu(ctrl) || !oob) && flash_dma_buf_ok(buf)) {
+	} else if (use_dma(ctrl) && (has_edu(ctrl) || !oob) && flash_dma_buf_ok(buf)) {
 		if (ctrl->dma_trans(host, addr, (u32 *)buf, oob, mtd->writesize,
 				    CMD_PROGRAM_PAGE))
-
 			ret = -EIO;
 
 		goto out;