diff options
Diffstat (limited to 'drivers/gpio/gpio-ks8695.c')
| -rw-r--r-- | drivers/gpio/gpio-ks8695.c | 319 |
1 files changed, 319 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-ks8695.c b/drivers/gpio/gpio-ks8695.c new file mode 100644 index 00000000000..a3ac66ea364 --- /dev/null +++ b/drivers/gpio/gpio-ks8695.c @@ -0,0 +1,319 @@ +/* + * arch/arm/mach-ks8695/gpio.c + * + * Copyright (C) 2006 Andrew Victor + * Updated to GPIOLIB, Copyright 2008 Simtec Electronics + * Daniel Silverstone <dsilvers@simtec.co.uk> + * + * 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/gpio.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/init.h> +#include <linux/debugfs.h> +#include <linux/seq_file.h> +#include <linux/module.h> +#include <linux/io.h> + +#include <mach/hardware.h> +#include <asm/mach/irq.h> + +#include <mach/regs-gpio.h> +#include <mach/gpio-ks8695.h> + +/* + * Configure a GPIO line for either GPIO function, or its internal + * function (Interrupt, Timer, etc). + */ +static void 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 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 */ + irq_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. + */ +static int ks8695_gpio_direction_input(struct gpio_chip *gc, 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; +} + + +/* + * Configure the GPIO line as an output, with default state. + */ +static int ks8695_gpio_direction_output(struct gpio_chip *gc, + unsigned int pin, 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 |= IOPD(pin); + else + x &= ~IOPD(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; +} + + +/* + * Set the state of an output GPIO line. + */ +static void ks8695_gpio_set_value(struct gpio_chip *gc, + unsigned int pin, 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 |= IOPD(pin); + else + x &= ~IOPD(pin); + __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPD); + + local_irq_restore(flags); +} + + +/* + * Read the state of a GPIO line. + */ +static int ks8695_gpio_get_value(struct gpio_chip *gc, unsigned int pin) +{ + unsigned long x; + + if (pin > KS8695_GPIO_15) + return -EINVAL; + + x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD); + return (x & IOPD(pin)) != 0; +} + + +/* + * Map GPIO line to IRQ number. + */ +static int ks8695_gpio_to_irq(struct gpio_chip *gc, unsigned int pin) +{ + if (pin > KS8695_GPIO_3) /* only GPIO 0..3 can generate IRQ */ + return -EINVAL; + + return gpio_irq[pin]; +} + +/* + * 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); + +/* GPIOLIB interface */ + +static struct gpio_chip ks8695_gpio_chip = { + .label = "KS8695", + .direction_input = ks8695_gpio_direction_input, + .direction_output = ks8695_gpio_direction_output, + .get = ks8695_gpio_get_value, + .set = ks8695_gpio_set_value, + .to_irq = ks8695_gpio_to_irq, + .base = 0, + .ngpio = 16, + .can_sleep = 0, +}; + +/* Register the GPIOs */ +void ks8695_register_gpios(void) +{ + if (gpiochip_add(&ks8695_gpio_chip)) + printk(KERN_ERR "Unable to register core GPIOs\n"); +} + +/* .... Debug interface ..................................................... */ + +#ifdef CONFIG_DEBUG_FS + +static int ks8695_gpio_show(struct seq_file *s, void *unused) +{ + unsigned int enable[] = { IOPC_IOEINT0EN, IOPC_IOEINT1EN, IOPC_IOEINT2EN, IOPC_IOEINT3EN, IOPC_IOTIM0EN, IOPC_IOTIM1EN }; + unsigned int intmask[] = { IOPC_IOEINT0TM, IOPC_IOEINT1TM, IOPC_IOEINT2TM, IOPC_IOEINT3TM }; + unsigned long mode, ctrl, data; + int i; + + mode = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM); + ctrl = __raw_readl(KS8695_GPIO_VA + KS8695_IOPC); + data = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD); + + seq_printf(s, "Pin\tI/O\tFunction\tState\n\n"); + + for (i = KS8695_GPIO_0; i <= KS8695_GPIO_15 ; i++) { + seq_printf(s, "%i:\t", i); + + seq_printf(s, "%s\t", (mode & IOPM(i)) ? "Output" : "Input"); + + if (i <= KS8695_GPIO_3) { + if (ctrl & enable[i]) { + seq_printf(s, "EXT%i ", i); + + switch ((ctrl & intmask[i]) >> (4 * i)) { + case IOPC_TM_LOW: + seq_printf(s, "(Low)"); break; + case IOPC_TM_HIGH: + seq_printf(s, "(High)"); break; + case IOPC_TM_RISING: + seq_printf(s, "(Rising)"); break; + case IOPC_TM_FALLING: + seq_printf(s, "(Falling)"); break; + case IOPC_TM_EDGE: + seq_printf(s, "(Edges)"); break; + } + } + else + seq_printf(s, "GPIO\t"); + } + else if (i <= KS8695_GPIO_5) { + if (ctrl & enable[i]) + seq_printf(s, "TOUT%i\t", i - KS8695_GPIO_4); + else + seq_printf(s, "GPIO\t"); + } + else + seq_printf(s, "GPIO\t"); + + seq_printf(s, "\t"); + + seq_printf(s, "%i\n", (data & IOPD(i)) ? 1 : 0); + } + return 0; +} + +static int ks8695_gpio_open(struct inode *inode, struct file *file) +{ + return single_open(file, ks8695_gpio_show, NULL); +} + +static const struct file_operations ks8695_gpio_operations = { + .open = ks8695_gpio_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static int __init ks8695_gpio_debugfs_init(void) +{ + /* /sys/kernel/debug/ks8695_gpio */ + (void) debugfs_create_file("ks8695_gpio", S_IFREG | S_IRUGO, NULL, NULL, &ks8695_gpio_operations); + return 0; +} +postcore_initcall(ks8695_gpio_debugfs_init); + +#endif |