From mboxrd@z Thu Jan 1 00:00:00 1970 From: Philipp Hachtmann Subject: Re: [PATCH] USB: ftdi_sio: add GPIO support Date: Mon, 16 Jun 2014 09:15:55 +0200 Message-ID: <539E99AB.9030907@hachti.de> References: <1402320115-13171-1-git-send-email-x-linux@infra-silbe.de> <20140610105631.GA10256@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140610105631.GA10256@localhost> Sender: linux-kernel-owner@vger.kernel.org To: Johan Hovold , Sascha Silbe Cc: Johan Hovold , Linus Walleij , Alexandre Courbot , Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-gpio@vger.kernel.org Hi, > Would this patch interfere with adding support for using the CBUS pins > as GPIOs while operating in normal UART mode? Most interesting question! >> Care was taken to prevent using GPIOs if the serial device is in use >> and vice versa. What about CBUS GPIO support? > Ok, so we're not extending the serial driver with support for > controlling some unused pins (e.g. CBUS) but rather implementing support > for a mutually exclusive mode. For bitbang mode (on the data lines) - yes. But for bitbang on CBUS - no. I have sent a proposal a few weeks ago but Greg did not like special sysfs stuff :-P He asked me to use the GPIO subsystem for the CBUS pins. I am out of time until july. But I still want and need CBUS support in parallel with serial/FIFO operation. Regards Philipp