From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:6f8:1178:4:290:27ff:fe1d:cc33]) by canuck.infradead.org with esmtps (Exim 4.72 #1 (Red Hat Linux)) id 1P9BnF-0005jQ-Ne for barebox@lists.infradead.org; Fri, 22 Oct 2010 07:12:03 +0000 From: Juergen Beisert Date: Fri, 22 Oct 2010 09:11:41 +0200 References: <201010181843.39263.jbe@pengutronix.de> <20101021200902.GB22139@pengutronix.de> In-Reply-To: <20101021200902.GB22139@pengutronix.de> MIME-Version: 1.0 Content-Disposition: inline Message-Id: <201010220911.41518.jbe@pengutronix.de> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH] Add GPIO support and GPIO setup features to the S3C processors To: barebox@lists.infradead.org Hi Sascha, Sascha Hauer wrote: > On Mon, Oct 18, 2010 at 06:43:39PM +0200, Juergen Beisert wrote: > > From: Juergen Beisert > > Subject: Add GPIO support and GPIO setup features to the S3C processors > > > > This patch adds genetic GPIO support to all S3C2440 processor based > > systems. Also it adds definitions to setup the pin multiplexer in a way > > the other architectures do. > > > > Note: Tested on a S3C2440 based system only. But should work on an > > S3C2410, too. > > > > Signed-off-by: Juergen Beisert > > > > --- > > arch/arm/Kconfig | 1 > > arch/arm/mach-s3c24xx/Makefile | 2 > > arch/arm/mach-s3c24xx/gpio-s3c24x0.c | 170 ++++++++ > > arch/arm/mach-s3c24xx/include/mach/gpio.h | 31 + > > arch/arm/mach-s3c24xx/include/mach/iomux-s3c24x0.h | 426 > > +++++++++++++++++++++ 5 files changed, 629 insertions(+), 1 deletion(-) > > > > Index: barebox-2010.10.0/arch/arm/mach-s3c24xx/gpio-s3c24x0.c > > =================================================================== > > --- /dev/null > > +++ barebox-2010.10.0/arch/arm/mach-s3c24xx/gpio-s3c24x0.c > > @@ -0,0 +1,170 @@ > > +/* > > + * This program is free software; you can redistribute it and/or > > + * modify it under the terms of the GNU General Public License as > > + * published by the Free Software Foundation; either version 2 of > > + * the License, or (at your option) any later version. > > + * > > + * This program is distributed in the hope that it will be useful, > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > > + * GNU General Public License for more details. > > + * > > + * You should have received a copy of the GNU General Public License > > + * along with this program; if not, write to the Free Software > > + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, > > + * MA 02111-1307 USA > > + */ > > + > > +#include > > +#include > > +#include > > +#include > > +#include > > + > > +static const unsigned char group_offset[] = > > +{ > > + 0x00, /* GPA */ > > + 0x10, /* GPB */ > > + 0x20, /* GPC */ > > + 0x30, /* GPD */ > > + 0x40, /* GPE */ > > + 0x50, /* GPF */ > > + 0x60, /* GPG */ > > + 0x70, /* GPH */ > > +#ifdef CONFIG_CPU_S3C2440 > > + 0xd0, /* GPJ */ > > +#endif > > +}; > > + > > +void gpio_set_value(unsigned gpio, int value) > > +{ > > + unsigned group = gpio >> 5; > > + unsigned bit = gpio % 32; > > + unsigned offset; > > + uint32_t reg; > > + > > + offset = group_offset[group]; > > + > > + reg = readl(GPADAT + offset); > > + reg &= ~(1 << bit); > > + reg |= (!!value) << bit; > > + writel(reg, GPADAT + offset); > > +} > > + > > +int gpio_direction_input(unsigned gpio) > > +{ > > + unsigned group = gpio >> 5; > > + unsigned bit = gpio % 32; > > + unsigned offset; > > + uint32_t reg; > > + > > + offset = group_offset[group]; > > + > > + reg = readl(GPACON + offset); > > + reg &= ~(0x3 << (bit << 1)); > > + writel(reg, GPACON + offset); > > + > > + return 0; > > +} > > + > > + > > +int gpio_direction_output(unsigned gpio, int value) > > +{ > > + unsigned group = gpio >> 5; > > + unsigned bit = gpio % 32; > > + unsigned offset; > > + uint32_t reg; > > + > > + offset = group_offset[group]; > > + > > + /* value */ > > + reg = readl(GPADAT + offset); > > + reg &= ~(1 << bit); > > + reg |= (!!value) << bit; > > + writel(reg, GPADAT + offset); > > You can call gpio_set_value here. Hmm, right. Will change it. > > + > > + /* direction */ > > + if (group == 0) { /* GPA is special */ > > + reg = readl(GPACON); > > + reg &= ~(1 << bit); > > + writel(reg, GPACON); > > + } else { > > gpio_direction_input does not have this special handling. Is this > correct? The GPA pin group can only be GPIO outputs *or* their native feature enabled (addressbus lines for example). But you are right, I should catch this error if someone tries to read from a GPA group pin. jbe -- Pengutronix e.K. | Juergen Beisert | Linux Solutions for Science and Industry | Phone: +49-8766-939 228 | Vertretung Sued/Muenchen, Germany | Fax: +49-5121-206917-5555 | Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de/ | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox