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Message-ID: <e451d814-2d10-6cb6-3402-6d1580ddbce2@linaro.org>
Date:   Fri, 18 Feb 2022 13:25:00 +0000
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Subject: Re: [PATCH v3 4/4] mtd: core: Fix a conflict between MTD and NVMEM on
 wp-gpios property
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To:     Christophe Kerello <christophe.kerello@foss.st.com>,
        miquel.raynal@bootlin.com, richard@nod.at, vigneshr@ti.com,
        robh+dt@kernel.org, p.yadav@ti.com
Cc:     linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-stm32@st-md-mailman.stormreply.com,
        devicetree@vger.kernel.org, chenshumin86@sina.com,
        stable@vger.kernel.org
References: <20220217144755.270679-1-christophe.kerello@foss.st.com>
 <20220217144755.270679-5-christophe.kerello@foss.st.com>
From:   Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
In-Reply-To: <20220217144755.270679-5-christophe.kerello@foss.st.com>
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On 17/02/2022 14:47, Christophe Kerello wrote:
> Wp-gpios property can be used on NVMEM nodes and the same property can
> be also used on MTD NAND nodes. In case of the wp-gpios property is
> defined at NAND level node, the GPIO management is done at NAND driver
> level. Write protect is disabled when the driver is probed or resumed
> and is enabled when the driver is released or suspended.
> 
> When no partitions are defined in the NAND DT node, then the NAND DT node
> will be passed to NVMEM framework. If wp-gpios property is defined in
> this node, the GPIO resource is taken twice and the NAND controller
> driver fails to probe.
> 
> A new Boolean flag named ignore_wp has been added in nvmem_config.
> In case ignore_wp is set, it means that the GPIO is handled by the
> provider. Lets set this flag in MTD layer to avoid the conflict on
> wp_gpios property.
> 
> Fixes: 2a127da461a9 ("nvmem: add support for the write-protect pin")
> Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com>
> Cc: stable@vger.kernel.org


Applied thanks,

--srini

> ---
> Changes in v3:
>   - add a fixes tag
>   - rename skip_wp_gpio by ignore_wp in nvmen_config.
> 
>   drivers/mtd/mtdcore.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
> index 70f492dce158..eef87b28d6c8 100644
> --- a/drivers/mtd/mtdcore.c
> +++ b/drivers/mtd/mtdcore.c
> @@ -546,6 +546,7 @@ static int mtd_nvmem_add(struct mtd_info *mtd)
>   	config.stride = 1;
>   	config.read_only = true;
>   	config.root_only = true;
> +	config.ignore_wp = true;
>   	config.no_of_node = !of_device_is_compatible(node, "nvmem-cells");
>   	config.priv = mtd;
>   
> @@ -833,6 +834,7 @@ static struct nvmem_device *mtd_otp_nvmem_register(struct mtd_info *mtd,
>   	config.owner = THIS_MODULE;
>   	config.type = NVMEM_TYPE_OTP;
>   	config.root_only = true;
> +	config.ignore_wp = true;
>   	config.reg_read = reg_read;
>   	config.size = size;
>   	config.of_node = np;