On 7/31/2012 11:18 PM, Vikram Narayanan wrote:
Driver for BCM2835 SoC. This gives the basic functionality of setting/clearing the output.
Signed-off-by: Vikram Narayananvikram186@gmail.com
arch/arm/include/asm/arch-bcm2835/gpio.h | 71 ++++++++++++++++++++++++ drivers/gpio/Makefile | 1 + drivers/gpio/bcm2835_gpio.c | 88 ++++++++++++++++++++++++++++++ 3 files changed, 160 insertions(+), 0 deletions(-) create mode 100644 arch/arm/include/asm/arch-bcm2835/gpio.h create mode 100644 drivers/gpio/bcm2835_gpio.c
diff --git a/arch/arm/include/asm/arch-bcm2835/gpio.h b/arch/arm/include/asm/arch-bcm2835/gpio.h new file mode 100644 index 0000000..515456a --- /dev/null +++ b/arch/arm/include/asm/arch-bcm2835/gpio.h @@ -0,0 +1,71 @@ +/*
- Copyright (C) 2012 Vikram Narayananan
- *vikram186@gmail.com
- 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
- */
+#ifndef _BCM2835_GPIO_H_ +#define _BCM2835_GPIO_H_
+#define BCM2835_GPIO_BASE 0x7E200000 +#define BCM2835_GPIO_COUNT 53
GPIO count should be 54 to make the gpio_is_valid work correctly when the gpio is 53. Will fix in v4.
Any other comments?
+#define BCM2835_GPIO_FSEL_MASK 0x7 +#define BCM2835_GPIO_INPUT 0x0 +#define BCM2835_GPIO_OUTPUT 0x1 +#define BCM2835_GPIO_ALT0 0x2 +#define BCM2835_GPIO_ALT1 0x3 +#define BCM2835_GPIO_ALT2 0x4 +#define BCM2835_GPIO_ALT3 0x5 +#define BCM2835_GPIO_ALT4 0x6 +#define BCM2835_GPIO_ALT5 0x7
+#define BCM2835_GPIO_COMMON_BANK(gpio) ((gpio< 32) ? 0 : 1) +#define BCM2835_GPIO_COMMON_SHIFT(gpio) (gpio& 0x1f)
+#define BCM2835_GPIO_FSEL_BANK(gpio) (gpio / 10) +#define BCM2835_GPIO_FSEL_SHIFT(gpio) ((gpio % 10) * 3)
+struct bcm_gpio_regs {
- u32 gpfsel[6];
- u32 reserved1;
- u32 gpset[2];
- u32 reserved2;
- u32 gpclr[2];
- u32 reserved3;
- u32 gplev[2];
- u32 reserved4;
- u32 gpeds[2];
- u32 reserved5;
- u32 gpren[2];
- u32 reserved6;
- u32 gpfen[2];
- u32 reserved7;
- u32 gphen[2];
- u32 reserved8;
- u32 gplen[2];
- u32 reserved9;
- u32 gparen[2];
- u32 reserved10;
- u32 gppud;
- u32 gppudclk[2];
+};
+#endif /* _BCM2835_GPIO_H_ */ diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index 32a2474..8d2f2b2 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -40,6 +40,7 @@ COBJS-$(CONFIG_TEGRA_GPIO) += tegra_gpio.o COBJS-$(CONFIG_DA8XX_GPIO) += da8xx_gpio.o COBJS-$(CONFIG_ALTERA_PIO) += altera_pio.o COBJS-$(CONFIG_MPC83XX_GPIO) += mpc83xx_gpio.o +COBJS-$(CONFIG_BCM2835_GPIO) += bcm2835_gpio.o
COBJS := $(COBJS-y) SRCS := $(COBJS:.o=.c) diff --git a/drivers/gpio/bcm2835_gpio.c b/drivers/gpio/bcm2835_gpio.c new file mode 100644 index 0000000..eb02efa --- /dev/null +++ b/drivers/gpio/bcm2835_gpio.c @@ -0,0 +1,88 @@ +/*
- Copyright (C) 2012 Vikram Narayananan
- *vikram186@gmail.com
- 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/gpio.h> +#include<asm/io.h>
+inline int gpio_is_valid(unsigned gpio) +{
- return (gpio< BCM2835_GPIO_COUNT);
+}
+int gpio_request(unsigned gpio, const char *label) +{
- return gpio_is_valid(gpio);
+}
+int gpio_free(unsigned gpio) +{
- return 0;
+}
+int gpio_direction_input(unsigned gpio) +{
- struct bcm_gpio_regs *reg = (struct bcm_gpio_regs *)BCM2835_GPIO_BASE;
- unsigned val;
- val = readl(®->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]);
- val&= ~(BCM2835_GPIO_FSEL_MASK<< BCM2835_GPIO_FSEL_SHIFT(gpio));
- val |= (BCM2835_GPIO_INPUT<< BCM2835_GPIO_FSEL_SHIFT(gpio));
- writel(val, reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]);
- }
+int gpio_direction_output(unsigned gpio, int value) +{
- struct bcm_gpio_regs *reg = (struct bcm_gpio_regs *)BCM2835_GPIO_BASE;
- unsigned val;
- if (value)
gpio_set_value(gpio, value);- val = readl(®->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]);
- val&= ~(BCM2835_GPIO_FSEL_MASK<< BCM2835_GPIO_FSEL_SHIFT(gpio));
- val |= (BCM2835_GPIO_OUTPUT<< BCM2835_GPIO_FSEL_SHIFT(gpio));
- writel(val, reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]);
+}
+int gpio_get_value(unsigned gpio) +{
- struct bcm_gpio_regs *reg = (struct bcm_gpio_regs *)BCM2835_GPIO_BASE;
- unsigned val;
- val = readl(®->gplev[BCM2835_GPIO_COMMON_BANK(gpio)]);
- return (val>> BCM2835_GPIO_COMMON_SHIFT(gpio))& 0x1;
+}
+int gpio_set_value(unsigned gpio, int value) +{
- struct bcm_gpio_regs *reg = (struct bcm_gpio_regs *)BCM2835_GPIO_BASE;
- u32 *output_reg = value ? reg->gpset : reg->gpclr;
- writel(1<< BCM2835_GPIO_COMMON_SHIFT(gpio),
output_reg[BCM2835_GPIO_COMMON_BANK(gpio)]);- return 0;
+}