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From: Linus Walleij <linus.walleij@linaro.org>
To: Tobias Junghans <tobias.junghans@inhub.de>
Cc: Linux Input <linux-input@vger.kernel.org>,
	Rishi Gupta <gupt21@gmail.com>, Jiri Kosina <jikos@kernel.org>,
	Benjamin Tissoires <benjamin.tissoires@redhat.com>
Subject: Re: [PATCH 2/2] HID: mcp2221: configure GP pins for GPIO function
Date: Fri, 17 Sep 2021 01:13:58 +0200	[thread overview]
Message-ID: <CACRpkdZSmiVPOY8==pAhnUnYUn5xv6Wf5-tKEEJrpcqPF47++w@mail.gmail.com> (raw)
In-Reply-To: <20210818152743.163929-2-tobias.junghans@inhub.de>

On Wed, Aug 18, 2021 at 5:28 PM Tobias Junghans
<tobias.junghans@inhub.de> wrote:

> Per default the GP pins of an MCP2221 are designated to a certain
> dedicated or alternate function. While it's possible to change these
> defaults by manually updating the internal flash, it's much more
> convenient and safe to configure the GP pins as GPIOs automatically
> at runtime whenever the corresponding GPIO line is requested. The
> previous setting is restored as soon as the GPIO line is freed again.
>
> Signed-off-by: Tobias Junghans <tobias.junghans@inhub.de>

My sympathies are usually on the side of users trying to make
use of their hardware and they should be able to.

For other wrong configured GPIO expanders such as FTDI
a publicly available firmware reflash tool exists, and if that does
not exist for this hardware, I think this approach is legitimate.

Acked-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij

  parent reply	other threads:[~2021-09-16 23:14 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-18 15:27 [PATCH 1/2] HID: mcp2221: enable HID I/O during probe Tobias Junghans
2021-08-18 15:27 ` [PATCH 2/2] HID: mcp2221: configure GP pins for GPIO function Tobias Junghans
     [not found]   ` <CALUj-gtmN70HwzvtsO7rss0LXboFC0h9Dgfakt6UEvC_6FdAwA@mail.gmail.com>
2021-08-20  7:18     ` Tobias Junghans
2021-08-30  9:11       ` rishi gupta
2021-08-30 13:09         ` Tobias Junghans
2021-08-30 13:17           ` rishi gupta
2021-08-30 13:30             ` Tobias Junghans
2021-09-02  7:13               ` rishi gupta
2021-09-16 23:13   ` Linus Walleij [this message]
2021-09-19 10:42     ` rishi gupta
2021-09-24 17:36       ` Jim Posen
2022-04-06 15:54 ` [PATCH 1/2] HID: mcp2221: enable HID I/O during probe rishi gupta

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