| /* |
| * arch/arm/plat-orion/gpio.c |
| * |
| * Marvell Orion SoC GPIO handling. |
| * |
| * 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/irq.h> |
| #include <linux/module.h> |
| #include <linux/spinlock.h> |
| #include <linux/bitops.h> |
| #include <linux/io.h> |
| #include <asm/gpio.h> |
| |
| static DEFINE_SPINLOCK(gpio_lock); |
| static const char *gpio_label[GPIO_MAX]; /* non null for allocated GPIOs */ |
| static unsigned long gpio_valid[BITS_TO_LONGS(GPIO_MAX)]; |
| |
| static inline void __set_direction(unsigned pin, int input) |
| { |
| u32 u; |
| |
| u = readl(GPIO_IO_CONF(pin)); |
| if (input) |
| u |= 1 << (pin & 31); |
| else |
| u &= ~(1 << (pin & 31)); |
| writel(u, GPIO_IO_CONF(pin)); |
| } |
| |
| static void __set_level(unsigned pin, int high) |
| { |
| u32 u; |
| |
| u = readl(GPIO_OUT(pin)); |
| if (high) |
| u |= 1 << (pin & 31); |
| else |
| u &= ~(1 << (pin & 31)); |
| writel(u, GPIO_OUT(pin)); |
| } |
| |
| |
| /* |
| * 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", __func__, pin); |
| return -EINVAL; |
| } |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| |
| /* |
| * Some callers might not have used gpio_request(), |
| * so flag this pin as requested now. |
| */ |
| if (gpio_label[pin] == NULL) |
| gpio_label[pin] = "?"; |
| |
| /* |
| * Configure GPIO direction. |
| */ |
| __set_direction(pin, 1); |
| |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL(gpio_direction_input); |
| |
| int gpio_direction_output(unsigned pin, int value) |
| { |
| unsigned long flags; |
| u32 u; |
| |
| if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) { |
| pr_debug("%s: invalid GPIO %d\n", __func__, pin); |
| return -EINVAL; |
| } |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| |
| /* |
| * Some callers might not have used gpio_request(), |
| * so flag this pin as requested now. |
| */ |
| if (gpio_label[pin] == NULL) |
| gpio_label[pin] = "?"; |
| |
| /* |
| * Disable blinking. |
| */ |
| u = readl(GPIO_BLINK_EN(pin)); |
| u &= ~(1 << (pin & 31)); |
| writel(u, GPIO_BLINK_EN(pin)); |
| |
| /* |
| * Configure GPIO output value. |
| */ |
| __set_level(pin, value); |
| |
| /* |
| * Configure GPIO direction. |
| */ |
| __set_direction(pin, 0); |
| |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL(gpio_direction_output); |
| |
| int gpio_get_value(unsigned pin) |
| { |
| int val; |
| |
| if (readl(GPIO_IO_CONF(pin)) & (1 << (pin & 31))) |
| val = readl(GPIO_DATA_IN(pin)) ^ readl(GPIO_IN_POL(pin)); |
| else |
| val = readl(GPIO_OUT(pin)); |
| |
| return (val >> (pin & 31)) & 1; |
| } |
| EXPORT_SYMBOL(gpio_get_value); |
| |
| void gpio_set_value(unsigned pin, int value) |
| { |
| unsigned long flags; |
| u32 u; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| |
| /* |
| * Disable blinking. |
| */ |
| u = readl(GPIO_BLINK_EN(pin)); |
| u &= ~(1 << (pin & 31)); |
| writel(u, GPIO_BLINK_EN(pin)); |
| |
| /* |
| * Configure GPIO output value. |
| */ |
| __set_level(pin, value); |
| |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| } |
| EXPORT_SYMBOL(gpio_set_value); |
| |
| int gpio_request(unsigned pin, const char *label) |
| { |
| unsigned long flags; |
| int ret; |
| |
| if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) { |
| pr_debug("%s: invalid GPIO %d\n", __func__, pin); |
| return -EINVAL; |
| } |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| if (gpio_label[pin] == NULL) { |
| gpio_label[pin] = label ? label : "?"; |
| ret = 0; |
| } else { |
| pr_debug("%s: GPIO %d already used as %s\n", |
| __func__, pin, gpio_label[pin]); |
| ret = -EBUSY; |
| } |
| 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", __func__, pin); |
| return; |
| } |
| |
| if (gpio_label[pin] == NULL) |
| pr_warning("%s: GPIO %d already freed\n", __func__, pin); |
| else |
| gpio_label[pin] = NULL; |
| } |
| EXPORT_SYMBOL(gpio_free); |
| |
| |
| /* |
| * Orion-specific GPIO API extensions. |
| */ |
| void __init orion_gpio_set_unused(unsigned pin) |
| { |
| /* |
| * Configure as output, drive low. |
| */ |
| __set_level(pin, 0); |
| __set_direction(pin, 0); |
| } |
| |
| void __init orion_gpio_set_valid(unsigned pin, int valid) |
| { |
| if (valid) |
| __set_bit(pin, gpio_valid); |
| else |
| __clear_bit(pin, gpio_valid); |
| } |
| |
| void orion_gpio_set_blink(unsigned pin, int blink) |
| { |
| unsigned long flags; |
| u32 u; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| |
| /* |
| * Set output value to zero. |
| */ |
| __set_level(pin, 0); |
| |
| u = readl(GPIO_BLINK_EN(pin)); |
| if (blink) |
| u |= 1 << (pin & 31); |
| else |
| u &= ~(1 << (pin & 31)); |
| writel(u, GPIO_BLINK_EN(pin)); |
| |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| } |
| EXPORT_SYMBOL(orion_gpio_set_blink); |
| |
| |
| /***************************************************************************** |
| * Orion GPIO IRQ |
| * |
| * GPIO_IN_POL register controls whether GPIO_DATA_IN will hold the same |
| * value of the line or the opposite value. |
| * |
| * Level IRQ handlers: DATA_IN is used directly as cause register. |
| * Interrupt are masked by LEVEL_MASK registers. |
| * Edge IRQ handlers: Change in DATA_IN are latched in EDGE_CAUSE. |
| * Interrupt are masked by EDGE_MASK registers. |
| * Both-edge handlers: Similar to regular Edge handlers, but also swaps |
| * the polarity to catch the next line transaction. |
| * This is a race condition that might not perfectly |
| * work on some use cases. |
| * |
| * Every eight GPIO lines are grouped (OR'ed) before going up to main |
| * cause register. |
| * |
| * EDGE cause mask |
| * data-in /--------| |-----| |----\ |
| * -----| |----- ---- to main cause reg |
| * X \----------------| |----/ |
| * polarity LEVEL mask |
| * |
| ****************************************************************************/ |
| static void gpio_irq_edge_ack(u32 irq) |
| { |
| int pin = irq_to_gpio(irq); |
| |
| writel(~(1 << (pin & 31)), GPIO_EDGE_CAUSE(pin)); |
| } |
| |
| static void gpio_irq_edge_mask(u32 irq) |
| { |
| int pin = irq_to_gpio(irq); |
| u32 u; |
| |
| u = readl(GPIO_EDGE_MASK(pin)); |
| u &= ~(1 << (pin & 31)); |
| writel(u, GPIO_EDGE_MASK(pin)); |
| } |
| |
| static void gpio_irq_edge_unmask(u32 irq) |
| { |
| int pin = irq_to_gpio(irq); |
| u32 u; |
| |
| u = readl(GPIO_EDGE_MASK(pin)); |
| u |= 1 << (pin & 31); |
| writel(u, GPIO_EDGE_MASK(pin)); |
| } |
| |
| static void gpio_irq_level_mask(u32 irq) |
| { |
| int pin = irq_to_gpio(irq); |
| u32 u; |
| |
| u = readl(GPIO_LEVEL_MASK(pin)); |
| u &= ~(1 << (pin & 31)); |
| writel(u, GPIO_LEVEL_MASK(pin)); |
| } |
| |
| static void gpio_irq_level_unmask(u32 irq) |
| { |
| int pin = irq_to_gpio(irq); |
| u32 u; |
| |
| u = readl(GPIO_LEVEL_MASK(pin)); |
| u |= 1 << (pin & 31); |
| writel(u, GPIO_LEVEL_MASK(pin)); |
| } |
| |
| static int gpio_irq_set_type(u32 irq, u32 type) |
| { |
| int pin = irq_to_gpio(irq); |
| struct irq_desc *desc; |
| u32 u; |
| |
| u = readl(GPIO_IO_CONF(pin)) & (1 << (pin & 31)); |
| if (!u) { |
| printk(KERN_ERR "orion gpio_irq_set_type failed " |
| "(irq %d, pin %d).\n", irq, pin); |
| return -EINVAL; |
| } |
| |
| desc = irq_desc + irq; |
| |
| /* |
| * Set edge/level type. |
| */ |
| if (type & (IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING)) { |
| desc->chip = &orion_gpio_irq_edge_chip; |
| } else if (type & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) { |
| desc->chip = &orion_gpio_irq_level_chip; |
| } else { |
| printk(KERN_ERR "failed to set irq=%d (type=%d)\n", irq, type); |
| return -EINVAL; |
| } |
| |
| /* |
| * Configure interrupt polarity. |
| */ |
| if (type == IRQ_TYPE_EDGE_RISING || type == IRQ_TYPE_LEVEL_HIGH) { |
| u = readl(GPIO_IN_POL(pin)); |
| u &= ~(1 << (pin & 31)); |
| writel(u, GPIO_IN_POL(pin)); |
| } else if (type == IRQ_TYPE_EDGE_FALLING || type == IRQ_TYPE_LEVEL_LOW) { |
| u = readl(GPIO_IN_POL(pin)); |
| u |= 1 << (pin & 31); |
| writel(u, GPIO_IN_POL(pin)); |
| } else if (type == IRQ_TYPE_EDGE_BOTH) { |
| u32 v; |
| |
| v = readl(GPIO_IN_POL(pin)) ^ readl(GPIO_DATA_IN(pin)); |
| |
| /* |
| * set initial polarity based on current input level |
| */ |
| u = readl(GPIO_IN_POL(pin)); |
| if (v & (1 << (pin & 31))) |
| u |= 1 << (pin & 31); /* falling */ |
| else |
| u &= ~(1 << (pin & 31)); /* rising */ |
| writel(u, GPIO_IN_POL(pin)); |
| } |
| |
| desc->status = (desc->status & ~IRQ_TYPE_SENSE_MASK) | type; |
| |
| return 0; |
| } |
| |
| struct irq_chip orion_gpio_irq_edge_chip = { |
| .name = "orion_gpio_irq_edge", |
| .ack = gpio_irq_edge_ack, |
| .mask = gpio_irq_edge_mask, |
| .unmask = gpio_irq_edge_unmask, |
| .set_type = gpio_irq_set_type, |
| }; |
| |
| struct irq_chip orion_gpio_irq_level_chip = { |
| .name = "orion_gpio_irq_level", |
| .mask = gpio_irq_level_mask, |
| .mask_ack = gpio_irq_level_mask, |
| .unmask = gpio_irq_level_unmask, |
| .set_type = gpio_irq_set_type, |
| }; |
| |
| void orion_gpio_irq_handler(int pinoff) |
| { |
| u32 cause; |
| int pin; |
| |
| cause = readl(GPIO_DATA_IN(pinoff)) & readl(GPIO_LEVEL_MASK(pinoff)); |
| cause |= readl(GPIO_EDGE_CAUSE(pinoff)) & readl(GPIO_EDGE_MASK(pinoff)); |
| |
| for (pin = pinoff; pin < pinoff + 8; pin++) { |
| int irq = gpio_to_irq(pin); |
| struct irq_desc *desc = irq_desc + irq; |
| |
| if (!(cause & (1 << (pin & 31)))) |
| continue; |
| |
| if ((desc->status & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH) { |
| /* Swap polarity (race with GPIO line) */ |
| u32 polarity; |
| |
| polarity = readl(GPIO_IN_POL(pin)); |
| polarity ^= 1 << (pin & 31); |
| writel(polarity, GPIO_IN_POL(pin)); |
| } |
| desc_handle_irq(irq, desc); |
| } |
| } |