[U-Boot] [PATCH 2/9] i.MX31: add a simple gpio driver

[Jean-Christophe PLAGNIOL-VILLARD]

On 17:59 Wed 04 Feb     , Guennadi Liakhovetski wrote:
> This is a minimal driver, so far only managing output. It will
> be used by the mxc_spi.c driver.
> 
> Signed-off-by: Guennadi Liakhovetski <lg at denx.de>
> ---
> 
> Jean-Christophe: also an ack from you, please.
I'd like to see a gpio_lib one day to simplify gpio use in u-boot

> 
>  drivers/gpio/Makefile            |    3 +-
>  drivers/gpio/mx31_gpio.c         |   71 ++++++++++++++++++++++++++++++++++++++
>  include/asm-arm/arch-mx31/mx31.h |    9 +++++
>  3 files changed, 82 insertions(+), 1 deletions(-)
>  create mode 100644 drivers/gpio/mx31_gpio.c
> 
> diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> index dd618ed..ce049e4 100644
> --- a/drivers/gpio/Makefile
> +++ b/drivers/gpio/Makefile
> @@ -25,7 +25,8 @@ include $(TOPDIR)/config.mk
>  
>  LIB 	:= $(obj)libgpio.a
>  
> -COBJS-$(CONFIG_PCA953X)	+= pca953x.o
> +COBJS-$(CONFIG_PCA953X)		+= pca953x.o
> +COBJS-$(CONFIG_MX31_GPIO)	+= mx31_gpio.o
>  
>  COBJS	:= $(COBJS-y)
>  SRCS 	:= $(COBJS:.o=.c)
> diff --git a/drivers/gpio/mx31_gpio.c b/drivers/gpio/mx31_gpio.c
> new file mode 100644
> index 0000000..871601f
> --- /dev/null
> +++ b/drivers/gpio/mx31_gpio.c
> @@ -0,0 +1,71 @@
> +/*
> + * Copyright (C) 2009
> + * Guennadi Liakhovetski, DEXN Software Engineering, <lg at denx.de>
> + *
> + * See file CREDITS for list of people who contributed to this
> + * project.
> + *
> + * 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 <common.h>
> +#include <asm/arch/mx31.h>
> +#include <asm/arch/mx31-regs.h>
> +
> +/* GPIO port description */
> +static unsigned long gpio_ports[] = {
> +	[0] = 0x53fcc000,
> +	[1] = 0x53fd0000,
> +	[2] = 0x53fa4000,
hardcoded?
> +};
> +
> +void mx31_gpio_direction(unsigned int gpio, enum mx31_gpio_direction direction)
						enum? do we really need this?
> +{
> +	unsigned int port = gpio >> 5;
> +	u32 l;
> +
> +	if (port > sizeof(gpio_ports) / sizeof(gpio_ports[0]) - 1)
ARRAY_SIZE?
> +		return;
> +
> +	gpio &= 0x1f;
> +
> +	l = __REG(gpio_ports[port] + 4);
> +	switch (direction) {
> +	case MX31_GPIO_DIRECTION_OUT:
> +		l |= 1 << gpio;
> +		break;
> +	case MX31_GPIO_DIRECTION_IN:
> +		l &= ~(1 << gpio);
> +	}
> +	__REG(gpio_ports[port] + 4) = l;
> +}
Best Regards,
J.