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: <20210517200002.6316-1-dariobin@libero.it>
In-Reply-To: <20210517200002.6316-1-dariobin@libero.it>
From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Wed, 19 May 2021 14:31:37 +0300
Message-ID: <CAHp75Vc0kmwuT21=bvpfUj+qAO1XmKEXUpxEEhx3TRZrQbR4Gw@mail.gmail.com>
Subject: Re: [PATCH v2 0/2] am335x: set pinmux registers from pins debug file
To:     Dario Binacchi <dariobin@libero.it>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Haojian Zhuang <haojian.zhuang@linaro.org>,
        Linus Walleij <linus.walleij@linaro.org>,
        Tony Lindgren <tony@atomide.com>,
        linux-arm Mailing List <linux-arm-kernel@lists.infradead.org>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
        Linux OMAP Mailing List <linux-omap@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Wed, May 19, 2021 at 3:58 AM Dario Binacchi <dariobin@libero.it> wrote:
>
>
> The patch was born from the need to change the slew rate of the LCD pins
> of a custom AM335x board during EMC tests. The AM335x, as described in a
> note in section 9.1 of its reference manual [1], is unable to write
> pinmux registers from user space. The series now makes it possible to
> write these registers from the pins debug file.

Even for debugfs it would be nice to have a piece of documentation.
Because pin control is a quite sensitive area and if something goes
wrong, it may damage the hardware.

> [1] https://www.ti.com/lit/ug/spruh73q/spruh73q.pdf


-- 
With Best Regards,
Andy Shevchenko