mtd: nand: correct extemded param page error handling

If the ONFI extended parameter page gives codeword_size == 0, the
extended ECC information is corrupt and should not be used. Currently,
we (correctly) avoid using the information, but we don't report the
error to the caller, so the caller doesn't know that we didn't
initialize ecc_strength_ds and ecc_step_ds. Now the caller can warn the
user that it does not have sufficient information.

This also removes the false and useless "ONFI extended param page
detected" debug message (it was printed even on the aforementioned
corruption, and for the success case, we don't really want a print).

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Huang Shijie <b32955@freescale.com>

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 00022b456dff99d8121f458fcac098151fc9fe6f..0b39d0c03f1e373beb0d0464a070e11408b90db1 100644 (file)
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -2912,12 +2912,13 @@ static int nand_flash_detect_ext_param_page(struct mtd_info *mtd,
        /* get the info we want. */
        ecc = (struct onfi_ext_ecc_info *)cursor;
 
-       if (ecc->codeword_size) {
-               chip->ecc_strength_ds = ecc->ecc_bits;
-               chip->ecc_step_ds = 1 << ecc->codeword_size;
+       if (!ecc->codeword_size) {
+               pr_debug("Invalid codeword size\n");
+               goto ext_out;
        }
 
-       pr_info("ONFI extended param page detected.\n");
+       chip->ecc_strength_ds = ecc->ecc_bits;
+       chip->ecc_step_ds = 1 << ecc->codeword_size;
        ret = 0;
 
 ext_out: