mtd: rawnand: pl353: Ensure program page operations are successful

The NAND core complies with the ONFI specification, which itself
mentions that after any program or erase operation, a status check
should be performed to see whether the operation was finished *and*
successful.

The NAND core offers helpers to finish a page write (sending the
"PAGE PROG" command, waiting for the NAND chip to be ready again, and
checking the operation status). But in some cases, advanced controller
drivers might want to optimize this and craft their own page write
helper to leverage additional hardware capabilities, thus not always
using the core facilities.

Some drivers, like this one, do not use the core helper to finish a page
write because the final cycles are automatically managed by the
hardware. In this case, the additional care must be taken to manually
perform the final status check.

Let's read the NAND chip status at the end of the page write helper and
return -EIO upon error.

Cc: Michal Simek <[email protected]>
Cc: [email protected]
Fixes: 08d8c62 ("mtd: rawnand: pl353: Add support for the ARM PL353 SMC NAND controller")
Signed-off-by: Miquel Raynal <[email protected]>
Tested-by: Michal Simek <[email protected]>
Link: https://lore.kernel.org/linux-mtd/[email protected]

Author: miquelraynal

drivers/mtd/nand/raw/pl35x-nand-controller.c

@@ -511,6 +511,7 @@ static int pl35x_nand_write_page_hwecc(struct nand_chip *chip,
 	u32 addr1 = 0, addr2 = 0, row;
 	u32 cmd_addr;
 	int i, ret;
+	u8 status;
 
 	ret = pl35x_smc_set_ecc_mode(nfc, chip, PL35X_SMC_ECC_CFG_MODE_APB);
 	if (ret)
@@ -563,6 +564,14 @@ static int pl35x_nand_write_page_hwecc(struct nand_chip *chip,
 	if (ret)
 		goto disable_ecc_engine;
 
+	/* Check write status on the chip side */
+	ret = nand_status_op(chip, &status);
+	if (ret)
+		goto disable_ecc_engine;
+
+	if (status & NAND_STATUS_FAIL)
+		ret = -EIO;
+
 disable_ecc_engine:
 	pl35x_smc_set_ecc_mode(nfc, chip, PL35X_SMC_ECC_CFG_MODE_BYPASS);