From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from conuserg-11.nifty.com ([210.131.2.78]) by bombadil.infradead.org with esmtps (Exim 4.85_2 #1 (Red Hat Linux)) id 1cAhNm-00050w-Qa for linux-mtd@lists.infradead.org; Sat, 26 Nov 2016 18:07:30 +0000 From: Masahiro Yamada To: linux-mtd@lists.infradead.org Cc: Masahiro Yamada , linux-kernel@vger.kernel.org, Boris Brezillon , Marek Vasut , Brian Norris , Richard Weinberger , David Woodhouse , Cyrille Pitchen Subject: [PATCH 01/39] mtd: nand: allow to set only one of ECC size and ECC strength from DT Date: Sun, 27 Nov 2016 03:05:47 +0900 Message-Id: <1480183585-592-2-git-send-email-yamada.masahiro@socionext.com> In-Reply-To: <1480183585-592-1-git-send-email-yamada.masahiro@socionext.com> References: <1480183585-592-1-git-send-email-yamada.masahiro@socionext.com> List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Currently, it is valid to specify both "nand-ecc-step-size" and "nand-ecc-strength", but not allowed to set only one of them. This requirement has a conflict with "nand-ecc-maximize"; this flag is used when you want the driver to choose the best ECC strength. If "nand-ecc-maximize" is set, "nand-ecc-strength" is very likely to be unset. It would be possible to make the if-conditional more complex by adding the check for the NAND_ECC_MAXIMIZE flag, but I chose to drop the check entirely. I thought of the situation where the hardware has a fixed ECC step size (so it can be hard-coded in the driver), whereas the ECC strength is configurable by software. In that case, we may want to only set "nand-ecc-strength" (or "nand-ecc-maximize") in DT. Signed-off-by: Masahiro Yamada --- The Denali NAND is the case. The ecc.size is fixed when the RTL is delivered, while the driver can choose ecc.strength from some supported values. For Intel and Altera, available ecc.strength are 8, 15. For Socionext UniPhier, available ecc.strength are 8, 16, 24. drivers/mtd/nand/nand_base.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index 8c74d8c..c1ed91d 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -4266,12 +4266,6 @@ static int nand_dt_init(struct nand_chip *chip) ecc_strength = of_get_nand_ecc_strength(dn); ecc_step = of_get_nand_ecc_step_size(dn); - if ((ecc_step >= 0 && !(ecc_strength >= 0)) || - (!(ecc_step >= 0) && ecc_strength >= 0)) { - pr_err("must set both strength and step size in DT\n"); - return -EINVAL; - } - if (ecc_mode >= 0) chip->ecc.mode = ecc_mode; -- 2.7.4