Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20210528072351.1639575-1-hs@denx.de> <20210528072351.1639575-3-hs@denx.de>
In-Reply-To: <20210528072351.1639575-3-hs@denx.de>
From:   Fabio Estevam <festevam@gmail.com>
Date:   Fri, 28 May 2021 10:55:51 -0300
Message-ID: <CAOMZO5Cq6BT_46tKGWMoLUvaHEzD-mbEF56S0TzWpQXtXRsVmQ@mail.gmail.com>
Subject: Re: [PATCH v1 2/2] mtd: devices: add support for microchip 48l640 EERAM
To:     Heiko Schocher <hs@denx.de>
Cc:     linux-mtd <linux-mtd@lists.infradead.org>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

Hi Heiko,

On Fri, May 28, 2021 at 4:26 AM Heiko Schocher <hs@denx.de> wrote:
>
> The Microchip 48l640 is a 8KByte EERAM connected via SPI.
>
> Signed-off-by: Heiko Schocher <hs@denx.de>
> ---
> I tried to use drivers/mtd/devices/mchp23k256.c but this
> driver does not use any status register and there seems
> slight differences in registers (no write enable register
> for example), so I decided to make a new driver.
>
> This driver sets the continuous mode bit in Status register,
> which states you can write continuous ... but after writting
> 32 bytes the chip goes into an undefined state, so driver now
> writes data in 32 byte chunks.
>
> I also tried to use regmap, but it leads in a lot of more code,
> and as this chip has only spi interface it makes no sense, or?
>
> Tested  this driver on board imx8mp-phyboard-pollux-rdk
> board, which is already in mainline.
>
> Made some tbot tests, which write at random offset random
> length bytes with dd and and random content. Reread the data
> after a reboot and compare with the written data. Works fine.

Works for me too on an imx7d based board, thanks:

Tested-by: Fabio Estevam <festevam@denx.de>