Sender: Guenter Roeck <groeck7@gmail.com>
To:     Alistair Francis <alistair23@gmail.com>,
        Andreas Kemnade <andreas@kemnade.info>
Cc:     Alistair Francis <alistair@alistair23.me>,
        Lee Jones <lee.jones@linaro.org>,
        Mark Brown <broonie@kernel.org>,
        Sascha Hauer <kernel@pengutronix.de>, lgirdwood@gmail.com,
        Rob Herring <robh+dt@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        rui.zhang@intel.com, devicetree <devicetree@vger.kernel.org>,
        linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        linux-hwmon@vger.kernel.org, amitk@kernel.org,
        linux-pm@vger.kernel.org, dl-linux-imx <linux-imx@nxp.com>,
        Shawn Guo <shawnguo@kernel.org>
References: <20211110122948.188683-1-alistair@alistair23.me>
 <20211110122948.188683-4-alistair@alistair23.me>
 <20211116000634.767dcdc0@aktux>
 <CAKmqyKPFOqWD7t6tC1Act97CVcY+yazrhwMLLr3j_wOyH50GTA@mail.gmail.com>
From:   Guenter Roeck <linux@roeck-us.net>
Subject: Re: [PATCH v15 3/8] mfd: simple-mfd-i2c: Enable support for the
 silergy,sy7636a
Message-ID: <00d68181-ad3b-17d2-0150-00029d399f0f@roeck-us.net>
Date:   Tue, 23 Nov 2021 07:39:05 -0800
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101
 Thunderbird/78.13.0
MIME-Version: 1.0
In-Reply-To: <CAKmqyKPFOqWD7t6tC1Act97CVcY+yazrhwMLLr3j_wOyH50GTA@mail.gmail.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 8bit
Precedence: bulk

On 11/23/21 4:14 AM, Alistair Francis wrote:
> On Tue, Nov 16, 2021 at 9:10 AM Andreas Kemnade <andreas@kemnade.info> wrote:
>>
>> Hi,
>>
>> this all creates a lot of question marks...
>> One of my main question is whether sy7636a = sy7636 (at least the
>> driver in the kobo vendor kernels does not have the "A" at the end,
>> whic does not necessarily mean a difference).
>>
>> https://www.silergy.com/products/panel_pmic
>> lists only a SY7636ARMC, so chances are good that the letters were just
>> stripped away by the driver developers. Printing on chip package is
>> cryptic so it is not that helpful. It is just "BWNBDA"
> 
> I don't have a definite answer for you. But I think it's sy7636a
> 
> The page you linked to above lists SY7636ARMC as well as SY7627RMC,
> SY7570RMC. That makes me think that the RMC is a generic suffix and
> this actual IC is the SY7636A.
> 

Almost all chips have an ordering suffix, indicating things like
temperature range or packaging. The datasheet says:

Ordering Information
SY7636 □(□□)□
             | Temperature Code (C)
          | Package Code (RM)
        | Optional Spec Code (A)

The datasheet otherwise refers to the chip as SY7636A.

Guenter