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Date:   Mon, 20 May 2019 14:44:36 +0200
From:   Miquel Raynal <miquel.raynal@bootlin.com>
To:     Kamal Dasu <kdasu.kdev@gmail.com>
Cc:     linux-mtd@lists.infradead.org,
        bcm-kernel-feedback-list@broadcom.com,
        linux-kernel@vger.kernel.org,
        Brian Norris <computersforpeace@gmail.com>,
        Richard Weinberger <richard@nod.at>,
        David Woodhouse <dwmw2@infradead.org>,
        Marek Vasut <marek.vasut@gmail.com>,
        Vignesh Raghavendra <vigneshr@ti.com>
Subject: Re: [PATCH 2/2] mtd: nand: raw: brcmnand: fallback to detected
 ecc-strength, ecc-step-size
Message-ID: <20190520144436.67e42f00@xps13>
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        <1558117914-35807-2-git-send-email-kdasu.kdev@gmail.com>
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Hi Kamal,

Kamal Dasu <kdasu.kdev@gmail.com> wrote on Fri, 17 May 2019 14:29:55
-0400:

> This change supports nand-ecc-step-size and nand-ecc-strenght fields in

                                                       strength

> brcmnand dt node to be  optional.

           DT            ^ extra space

> see: Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt
> 
> If both nand-ecc-strength and nand-ecc-step-size are not specified in
> device tree node for NAND, nand_base driver does detect onfi ext ecc

s/nand_base driver/the raw NAND layer/
s/onfi/ONFI/
s/ecc/ECC/

What is "ext"? Please use plain English here.

> info from ONFI extended parameter page for parts using ONFI >= 2.1. In

s/info/information/

> case of non-onfi NAND there could be a nand_id table entry with the ecc

s/ecc/ECC/

> info. If there is a valid  device tree entry for nand-ecc-strength and
> nand-ecc-step-size fields it still shall override the detected values.
> 
> Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
> ---
>  drivers/mtd/nand/raw/brcmnand/brcmnand.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> index ce0b8ff..e967b30 100644
> --- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> +++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> @@ -2144,6 +2144,16 @@ static int brcmnand_setup_dev(struct brcmnand_host *host)
>  		return -EINVAL;
>  	}
>  
> +	if (!(chip->ecc.size > 0 && chip->ecc.strength > 0) &&

Is the case where only size OR strength is valid handled?

> +	    (chip->base.eccreq.strength > 0 &&
> +	     chip->base.eccreq.step_size > 0)) {
> +		/* use detected ecc parameters */

                   Use          ECC

> +		chip->ecc.size = chip->base.eccreq.step_size;
> +		chip->ecc.strength = chip->base.eccreq.strength;
> +		pr_info("Using detected nand-ecc-step-size %d, nand-ecc-strength %d\n",
> +			chip->ecc.size, chip->ecc.strength);
> +	}
> +
>  	switch (chip->ecc.size) {
>  	case 512:
>  		if (chip->ecc.algo == NAND_ECC_HAMMING)


Thanks,
Miquèl