From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <50AD9E8E.7050402@atmel.com> Date: Thu, 22 Nov 2012 11:39:58 +0800 From: Josh Wu MIME-Version: 1.0 To: Nicolas Ferre Subject: Re: [PATCH] MTD: at91: atmel_nand: return bit flips for the PMECC read_page() References: <1353474863-28430-1-git-send-email-josh.wu@atmel.com> <50ACA764.3030002@atmel.com> In-Reply-To: <50ACA764.3030002@atmel.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: mikedunn@newsguy.com, plagnioj@jcrosoft.com, linux-mtd@lists.infradead.org, linux-arm-kernel@lists.infradead.org, dedekind1@gmail.com List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi, Nicolas On 11/21/2012 6:05 PM, Nicolas Ferre wrote: > On 11/21/2012 06:14 AM, Josh Wu : >> > Can we have more comment to figure out why it is needed please? I will add following comment in the commit message in the v2 version. Since the commit: 3f91e94f7f511de74c0d2abe08672ccdbdd1961c ("mtd: nand: read_page() returns max_bitflips ()") The ecc.read_page() method for nand drivers is changed to return the maximum number of bitflips instead of just returning 0. And the nand.h is also explain that. I would like to adapt to it. Best Regards, Josh Wu > > Best regards, > >> Signed-off-by: Josh Wu >> --- >> drivers/mtd/nand/atmel_nand.c | 13 +++++++++---- >> 1 file changed, 9 insertions(+), 4 deletions(-) >> >> diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c >> index 9144557..860dd36 100644 >> --- a/drivers/mtd/nand/atmel_nand.c >> +++ b/drivers/mtd/nand/atmel_nand.c >> @@ -723,6 +723,7 @@ static int pmecc_correction(struct mtd_info *mtd, u32 pmecc_stat, uint8_t *buf, >> struct atmel_nand_host *host = nand_chip->priv; >> int i, err_nbr, eccbytes; >> uint8_t *buf_pos; >> + int total_err = 0; >> >> eccbytes = nand_chip->ecc.bytes; >> for (i = 0; i < eccbytes; i++) >> @@ -750,12 +751,13 @@ normal_check: >> pmecc_correct_data(mtd, buf_pos, ecc, i, >> host->pmecc_bytes_per_sector, err_nbr); >> mtd->ecc_stats.corrected += err_nbr; >> + total_err += err_nbr; >> } >> } >> pmecc_stat >>= 1; >> } >> >> - return 0; >> + return total_err; >> } >> >> static int atmel_nand_pmecc_read_page(struct mtd_info *mtd, >> @@ -767,6 +769,7 @@ static int atmel_nand_pmecc_read_page(struct mtd_info *mtd, >> uint32_t *eccpos = chip->ecc.layout->eccpos; >> uint32_t stat; >> unsigned long end_time; >> + int bitflips = 0; >> >> pmecc_writel(host->ecc, CTRL, PMECC_CTRL_RST); >> pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DISABLE); >> @@ -789,11 +792,13 @@ static int atmel_nand_pmecc_read_page(struct mtd_info *mtd, >> } >> >> stat = pmecc_readl_relaxed(host->ecc, ISR); >> - if (stat != 0) >> - if (pmecc_correction(mtd, stat, buf, &oob[eccpos[0]]) != 0) >> + if (stat != 0) { >> + bitflips = pmecc_correction(mtd, stat, buf, &oob[eccpos[0]]); >> + if (bitflips < 0) >> return -EIO; >> + } >> >> - return 0; >> + return bitflips; >> } >> >> static int atmel_nand_pmecc_write_page(struct mtd_info *mtd, >> >