diff options
Diffstat (limited to 'arch/arm/mach-orion/gpio.c')
| -rw-r--r-- | arch/arm/mach-orion/gpio.c | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/arch/arm/mach-orion/gpio.c b/arch/arm/mach-orion/gpio.c new file mode 100644 index 000000000000..d5f00c86d616 --- /dev/null +++ b/arch/arm/mach-orion/gpio.c @@ -0,0 +1,225 @@ +/* + * arch/arm/mach-orion/gpio.c + * + * GPIO functions for Marvell Orion System On Chip + * + * Maintainer: Tzachi Perelstein <tzachi@marvell.com> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/spinlock.h> +#include <linux/bitops.h> +#include <asm/gpio.h> +#include <asm/arch/orion.h> +#include "common.h" + +static DEFINE_SPINLOCK(gpio_lock); +static unsigned long gpio_valid[BITS_TO_LONGS(GPIO_MAX)]; +static const char *gpio_label[GPIO_MAX]; /* non null for allocated GPIOs */ + +void __init orion_gpio_set_valid_pins(u32 pins) +{ + gpio_valid[0] = pins; +} + +/* + * GENERIC_GPIO primitives + */ +int gpio_direction_input(unsigned pin) +{ + unsigned long flags; + + if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) { + pr_debug("%s: invalid GPIO %d\n", __FUNCTION__, pin); + return -EINVAL; + } + + spin_lock_irqsave(&gpio_lock, flags); + + /* + * Some callers might have not used the gpio_request(), + * so flag this pin as requested now. + */ + if (!gpio_label[pin]) + gpio_label[pin] = "?"; + + orion_setbits(GPIO_IO_CONF, 1 << pin); + + spin_unlock_irqrestore(&gpio_lock, flags); + return 0; +} +EXPORT_SYMBOL(gpio_direction_input); + +int gpio_direction_output(unsigned pin, int value) +{ + unsigned long flags; + int mask; + + if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) { + pr_debug("%s: invalid GPIO %d\n", __FUNCTION__, pin); + return -EINVAL; + } + + spin_lock_irqsave(&gpio_lock, flags); + + /* + * Some callers might have not used the gpio_request(), + * so flag this pin as requested now. + */ + if (!gpio_label[pin]) + gpio_label[pin] = "?"; + + mask = 1 << pin; + orion_clrbits(GPIO_BLINK_EN, mask); + if (value) + orion_setbits(GPIO_OUT, mask); + else + orion_clrbits(GPIO_OUT, mask); + orion_clrbits(GPIO_IO_CONF, mask); + + spin_unlock_irqrestore(&gpio_lock, flags); + return 0; +} +EXPORT_SYMBOL(gpio_direction_output); + +int gpio_get_value(unsigned pin) +{ + int val, mask = 1 << pin; + + if (orion_read(GPIO_IO_CONF) & mask) + val = orion_read(GPIO_DATA_IN) ^ orion_read(GPIO_IN_POL); + else + val = orion_read(GPIO_OUT); + + return val & mask; +} +EXPORT_SYMBOL(gpio_get_value); + +void gpio_set_value(unsigned pin, int value) +{ + unsigned long flags; + int mask = 1 << pin; + + spin_lock_irqsave(&gpio_lock, flags); + + orion_clrbits(GPIO_BLINK_EN, mask); + if (value) + orion_setbits(GPIO_OUT, mask); + else + orion_clrbits(GPIO_OUT, mask); + + spin_unlock_irqrestore(&gpio_lock, flags); +} +EXPORT_SYMBOL(gpio_set_value); + +void orion_gpio_set_blink(unsigned pin, int blink) +{ + unsigned long flags; + int mask = 1 << pin; + + spin_lock_irqsave(&gpio_lock, flags); + + orion_clrbits(GPIO_OUT, mask); + if (blink) + orion_setbits(GPIO_BLINK_EN, mask); + else + orion_clrbits(GPIO_BLINK_EN, mask); + + spin_unlock_irqrestore(&gpio_lock, flags); +} +EXPORT_SYMBOL(orion_gpio_set_blink); + +int gpio_request(unsigned pin, const char *label) +{ + int ret = 0; + unsigned long flags; + + if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) { + pr_debug("%s: invalid GPIO %d\n", __FUNCTION__, pin); + return -EINVAL; + } + + spin_lock_irqsave(&gpio_lock, flags); + + if (gpio_label[pin]) { + pr_debug("%s: GPIO %d already used as %s\n", + __FUNCTION__, pin, gpio_label[pin]); + ret = -EBUSY; + } else + gpio_label[pin] = label ? label : "?"; + + spin_unlock_irqrestore(&gpio_lock, flags); + return ret; +} +EXPORT_SYMBOL(gpio_request); + +void gpio_free(unsigned pin) +{ + if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) { + pr_debug("%s: invalid GPIO %d\n", __FUNCTION__, pin); + return; + } + + if (!gpio_label[pin]) + pr_warning("%s: GPIO %d already freed\n", __FUNCTION__, pin); + else + gpio_label[pin] = NULL; +} +EXPORT_SYMBOL(gpio_free); + +/* Debug helper */ +void gpio_display(void) +{ + int i; + + for (i = 0; i < GPIO_MAX; i++) { + printk(KERN_DEBUG "Pin-%d: ", i); + + if (!test_bit(i, gpio_valid)) { + printk("non-GPIO\n"); + } else if (!gpio_label[i]) { + printk("GPIO, free\n"); + } else { + printk("GPIO, used by %s, ", gpio_label[i]); + if (orion_read(GPIO_IO_CONF) & (1 << i)) { + printk("input, active %s, level %s, edge %s\n", + ((orion_read(GPIO_IN_POL) >> i) & 1) ? "low" : "high", + ((orion_read(GPIO_LEVEL_MASK) >> i) & 1) ? "enabled" : "masked", + ((orion_read(GPIO_EDGE_MASK) >> i) & 1) ? "enabled" : "masked"); + } else { + printk("output, val=%d\n", (orion_read(GPIO_OUT) >> i) & 1); + } + } + } + + printk(KERN_DEBUG "MPP_0_7_CTRL (0x%08x) = 0x%08x\n", + MPP_0_7_CTRL, orion_read(MPP_0_7_CTRL)); + printk(KERN_DEBUG "MPP_8_15_CTRL (0x%08x) = 0x%08x\n", + MPP_8_15_CTRL, orion_read(MPP_8_15_CTRL)); + printk(KERN_DEBUG "MPP_16_19_CTRL (0x%08x) = 0x%08x\n", + MPP_16_19_CTRL, orion_read(MPP_16_19_CTRL)); + printk(KERN_DEBUG "MPP_DEV_CTRL (0x%08x) = 0x%08x\n", + MPP_DEV_CTRL, orion_read(MPP_DEV_CTRL)); + printk(KERN_DEBUG "GPIO_OUT (0x%08x) = 0x%08x\n", + GPIO_OUT, orion_read(GPIO_OUT)); + printk(KERN_DEBUG "GPIO_IO_CONF (0x%08x) = 0x%08x\n", + GPIO_IO_CONF, orion_read(GPIO_IO_CONF)); + printk(KERN_DEBUG "GPIO_BLINK_EN (0x%08x) = 0x%08x\n", + GPIO_BLINK_EN, orion_read(GPIO_BLINK_EN)); + printk(KERN_DEBUG "GPIO_IN_POL (0x%08x) = 0x%08x\n", + GPIO_IN_POL, orion_read(GPIO_IN_POL)); + printk(KERN_DEBUG "GPIO_DATA_IN (0x%08x) = 0x%08x\n", + GPIO_DATA_IN, orion_read(GPIO_DATA_IN)); + printk(KERN_DEBUG "GPIO_LEVEL_MASK (0x%08x) = 0x%08x\n", + GPIO_LEVEL_MASK, orion_read(GPIO_LEVEL_MASK)); + printk(KERN_DEBUG "GPIO_EDGE_CAUSE (0x%08x) = 0x%08x\n", + GPIO_EDGE_CAUSE, orion_read(GPIO_EDGE_CAUSE)); + printk(KERN_DEBUG "GPIO_EDGE_MASK (0x%08x) = 0x%08x\n", + GPIO_EDGE_MASK, orion_read(GPIO_EDGE_MASK)); +} |