diff options
Diffstat (limited to 'arch/arm/mach-ks8695/gpio.c')
| -rw-r--r-- | arch/arm/mach-ks8695/gpio.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/arch/arm/mach-ks8695/gpio.c b/arch/arm/mach-ks8695/gpio.c new file mode 100644 index 000000000000..b1aa3cb3d4a3 --- /dev/null +++ b/arch/arm/mach-ks8695/gpio.c @@ -0,0 +1,218 @@ +/* + * arch/arm/mach-ks8695/gpio.c + * + * Copyright (C) 2006 Andrew Victor + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * 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 <linux/kernel.h> +#include <linux/mm.h> +#include <linux/init.h> +#include <linux/module.h> + +#include <asm/io.h> +#include <asm/hardware.h> +#include <asm/mach/irq.h> + +#include <asm/arch/regs-gpio.h> +#include <asm/arch/gpio.h> + +/* + * Configure a GPIO line for either GPIO function, or its internal + * function (Interrupt, Timer, etc). + */ +static void __init_or_module ks8695_gpio_mode(unsigned int pin, short gpio) +{ + unsigned int enable[] = { IOPC_IOEINT0EN, IOPC_IOEINT1EN, IOPC_IOEINT2EN, IOPC_IOEINT3EN, IOPC_IOTIM0EN, IOPC_IOTIM1EN }; + unsigned long x, flags; + + if (pin > KS8695_GPIO_5) /* only GPIO 0..5 have internal functions */ + return; + + local_irq_save(flags); + + x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPC); + if (gpio) /* GPIO: set bit to 0 */ + x &= ~enable[pin]; + else /* Internal function: set bit to 1 */ + x |= enable[pin]; + __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPC); + + local_irq_restore(flags); +} + + +static unsigned short gpio_irq[] = { KS8695_IRQ_EXTERN0, KS8695_IRQ_EXTERN1, KS8695_IRQ_EXTERN2, KS8695_IRQ_EXTERN3 }; + +/* + * Configure GPIO pin as external interrupt source. + */ +int __init_or_module ks8695_gpio_interrupt(unsigned int pin, unsigned int type) +{ + unsigned long x, flags; + + if (pin > KS8695_GPIO_3) /* only GPIO 0..3 can generate IRQ */ + return -EINVAL; + + local_irq_save(flags); + + /* set pin as input */ + x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM); + x &= ~IOPM_(pin); + __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPM); + + local_irq_restore(flags); + + /* Set IRQ triggering type */ + set_irq_type(gpio_irq[pin], type); + + /* enable interrupt mode */ + ks8695_gpio_mode(pin, 0); + + return 0; +} +EXPORT_SYMBOL(ks8695_gpio_interrupt); + + + +/* .... Generic GPIO interface .............................................. */ + +/* + * Configure the GPIO line as an input. + */ +int __init_or_module gpio_direction_input(unsigned int pin) +{ + unsigned long x, flags; + + if (pin > KS8695_GPIO_15) + return -EINVAL; + + /* set pin to GPIO mode */ + ks8695_gpio_mode(pin, 1); + + local_irq_save(flags); + + /* set pin as input */ + x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM); + x &= ~IOPM_(pin); + __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPM); + + local_irq_restore(flags); + + return 0; +} +EXPORT_SYMBOL(gpio_direction_input); + + +/* + * Configure the GPIO line as an output, with default state. + */ +int __init_or_module gpio_direction_output(unsigned int pin, unsigned int state) +{ + unsigned long x, flags; + + if (pin > KS8695_GPIO_15) + return -EINVAL; + + /* set pin to GPIO mode */ + ks8695_gpio_mode(pin, 1); + + local_irq_save(flags); + + /* set line state */ + x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD); + if (state) + x |= (1 << pin); + else + x &= ~(1 << pin); + __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPD); + + /* set pin as output */ + x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM); + x |= IOPM_(pin); + __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPM); + + local_irq_restore(flags); + + return 0; +} +EXPORT_SYMBOL(gpio_direction_output); + + +/* + * Set the state of an output GPIO line. + */ +void gpio_set_value(unsigned int pin, unsigned int state) +{ + unsigned long x, flags; + + if (pin > KS8695_GPIO_15) + return; + + local_irq_save(flags); + + /* set output line state */ + x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD); + if (state) + x |= (1 << pin); + else + x &= ~(1 << pin); + __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPD); + + local_irq_restore(flags); +} +EXPORT_SYMBOL(gpio_set_value); + + +/* + * Read the state of a GPIO line. + */ +int gpio_get_value(unsigned int pin) +{ + unsigned long x; + + if (pin > KS8695_GPIO_15) + return -EINVAL; + + x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD); + return (x & (1 << pin)) != 0; +} +EXPORT_SYMBOL(gpio_get_value); + + +/* + * Map GPIO line to IRQ number. + */ +int gpio_to_irq(unsigned int pin) +{ + if (pin > KS8695_GPIO_3) /* only GPIO 0..3 can generate IRQ */ + return -EINVAL; + + return gpio_irq[pin]; +} +EXPORT_SYMBOL(gpio_to_irq); + + +/* + * Map IRQ number to GPIO line. + */ +int irq_to_gpio(unsigned int irq) +{ + if ((irq < KS8695_IRQ_EXTERN0) || (irq > KS8695_IRQ_EXTERN3)) + return -EINVAL; + + return (irq - KS8695_IRQ_EXTERN0); +} +EXPORT_SYMBOL(irq_to_gpio); |