[PATCH 5/5] Add support for GPIO (BCM2835/Raspberry-Pi)
Jean-Christophe PLAGNIOL-VILLARD
plagnioj at jcrosoft.com
Tue Oct 9 07:31:42 EDT 2012
On 00:07 Tue 09 Oct , Carlo Caione wrote:
> Signed-off-by: Carlo Caione <carlo.caione at gmail.com>
> ---
> drivers/gpio/Kconfig | 3 +
> drivers/gpio/Makefile | 1 +
> drivers/gpio/gpio-bcm2835.c | 157 ++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 161 insertions(+)
> create mode 100644 drivers/gpio/gpio-bcm2835.c
>
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> index a0e9b58..aa27c0e 100644
> --- a/drivers/gpio/Kconfig
> +++ b/drivers/gpio/Kconfig
> @@ -6,6 +6,9 @@ if GPIOLIB
>
> menu "GPIO "
>
> +config GPIO_BCM2835
> + bool "GPIO support for BCM2835"
depends on ARHC_Bxxx
> +
> config GPIO_PL061
> bool "PrimeCell PL061 GPIO support"
> depends on ARM_AMBA
> diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> index e2e97d3..aecdf24 100644
> --- a/drivers/gpio/Makefile
> +++ b/drivers/gpio/Makefile
> @@ -1,4 +1,5 @@
> obj-$(CONFIG_GPIOLIB) += gpio.o
>
> +obj-$(CONFIG_GPIO_BCM2835) += gpio-bcm2835.o
> obj-$(CONFIG_GPIO_PL061) += gpio-pl061.o
> obj-$(CONFIG_GPIO_STMPE) += gpio-stmpe.o
> diff --git a/drivers/gpio/gpio-bcm2835.c b/drivers/gpio/gpio-bcm2835.c
> new file mode 100644
> index 0000000..8ee7086
> --- /dev/null
> +++ b/drivers/gpio/gpio-bcm2835.c
> @@ -0,0 +1,157 @@
> +/*
> + * Author: Carlo Caione <carlo at carlocaione.org>
> + *
> + * Based on linux/arch/arm/mach-bcm2708/bcm2708_gpio.c
> + *
> + * 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 <errno.h>
> +#include <malloc.h>
> +#include <io.h>
> +#include <gpio.h>
> +#include <init.h>
> +#include <mach/platform.h>
> +
> +#define GPIOFSEL(x) (0x00+(x)*4)
> +#define GPIOSET(x) (0x1c+(x)*4)
> +#define GPIOCLR(x) (0x28+(x)*4)
> +#define GPIOLEV(x) (0x34+(x)*4)
> +#define GPIOEDS(x) (0x40+(x)*4)
> +#define GPIOREN(x) (0x4c+(x)*4)
> +#define GPIOFEN(x) (0x58+(x)*4)
> +#define GPIOHEN(x) (0x64+(x)*4)
> +#define GPIOLEN(x) (0x70+(x)*4)
> +#define GPIOAREN(x) (0x7c+(x)*4)
> +#define GPIOAFEN(x) (0x88+(x)*4)
> +#define GPIOUD(x) (0x94+(x)*4)
> +#define GPIOUDCLK(x) (0x98+(x)*4)
> +
> +enum {
> + GPIO_FSEL_INPUT, GPIO_FSEL_OUTPUT,
> + GPIO_FSEL_ALT5, GPIO_FSEL_ALT_4,
> + GPIO_FSEL_ALT0, GPIO_FSEL_ALT1,
> + GPIO_FSEL_ALT2, GPIO_FSEL_ALT3,
> +};
> +
> +struct bcm2835_gpio_chip {
> + void __iomem *base;
> + struct gpio_chip chip;
> +};
> +
> +static int bcm2835_set_function(struct gpio_chip *chip, unsigned gpio, int function)
> +{
you should add one bank pre gpio_chip
> + struct bcm2835_gpio_chip *bcmgpio = container_of(chip, struct bcm2835_gpio_chip, chip);
> + void __iomem *base = bcmgpio->base;
> + unsigned gpiodir;
> + unsigned gpio_bank = gpio / 10;
> + unsigned gpio_field_offset = (gpio - 10 * gpio_bank) * 3;
so this will be dropped
> +
> + gpiodir = readl(base + GPIOFSEL(gpio_bank));
> + gpiodir &= ~(7 << gpio_field_offset);
> + gpiodir |= function << gpio_field_offset;
> + writel(gpiodir, base + GPIOFSEL(gpio_bank));
> + gpiodir = readl(base + GPIOFSEL(gpio_bank));
> +
> + return 0;
> +}
> +
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