[ARM] Orion: share GPIO handling code

Split off Orion GPIO handling code into plat-orion/, and add
support for multiple sets of (32) GPIO pins.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>

1 files changed, 239 insertions, 0 deletions

diff --git a/arch/arm/plat-orion/gpio.c b/arch/arm/plat-orion/gpio.c
new file mode 100644
index 000000000000..d86fc085e489
--- /dev/null
+++ b/arch/arm/plat-orion/gpio.c
@@ -0,0 +1,239 @@
+/*
+ * 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/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);