From mboxrd@z Thu Jan 1 00:00:00 1970 From: Geert Uytterhoeven Subject: Re: [PATCH] gpio: sn54hc595: new driver for GPIO shift registers chipsets Date: Mon, 8 Dec 2014 15:41:16 +0100 Message-ID: References: <1418048833-27658-1-git-send-email-zajec5@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-lb0-f169.google.com ([209.85.217.169]:52475 "EHLO mail-lb0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751041AbaLHOlS convert rfc822-to-8bit (ORCPT ); Mon, 8 Dec 2014 09:41:18 -0500 In-Reply-To: <1418048833-27658-1-git-send-email-zajec5@gmail.com> Sender: linux-gpio-owner@vger.kernel.org List-Id: linux-gpio@vger.kernel.org To: =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= Cc: Linus Walleij , Alexandre Courbot , "linux-gpio@vger.kernel.org" , Hauke Mehrtens , "devicetree@vger.kernel.org" Hi Rafa=C5=82, On Mon, Dec 8, 2014 at 3:27 PM, Rafa=C5=82 Mi=C5=82ecki wrote: > SN54HC595 and SN74HC595 are devices based on shift registers controll= ed > with 5 input signals (serial-in) and providing 8 outputs (parallel-ou= t). > > They are present on some Broadcom home router boards where manufactur= er > needed few extra GPIOs. > > This driver simply uses specified GPIOs to control shift registers an= d > registers another GPIO chip. So you can call it a GPIO extender. > > Due to the hardware design only output direction is supported. Readin= g > values is handled using tiny internal cache. > > Signed-off-by: Rafa=C5=82 Mi=C5=82ecki > --- > .../devicetree/bindings/gpio/gpio-sn54hc595.txt | 35 ++++ > drivers/gpio/Kconfig | 11 ++ > drivers/gpio/Makefile | 1 + > drivers/gpio/gpio-sn54hc595.c | 219 +++++++++++= ++++++++++ The '595 is already handled by drivers/gpio/gpio-74x164.c. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-= m68k.org In personal conversations with technical people, I call myself a hacker= =2E But when I'm talking to journalists I just say "programmer" or something li= ke that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html