[ARM] Orion: GPIO support

Signed-off-by: Tzachi Perelstein <tzachi@marvell.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Acked-by: David Brownell <david-b@pacbell.net>

arch/arm/Kconfig

@@ -337,6 +337,7 @@ config ARCH_ORION
 	bool "Marvell Orion"
 	depends on MMU
 	select PCI
+	select GENERIC_GPIO
 	help
 	  Support for Marvell Orion System on Chip family.
 

arch/arm/mach-orion/Makefile

-obj-y  += common.o addr-map.o pci.o
+obj-y  += common.o addr-map.o pci.o gpio.o

arch/arm/mach-orion/common.h

@@ -53,4 +53,12 @@ struct pci_bus *orion_pci_sys_scan_bus(int nr, struct pci_sys_data *sys);
 int orion_pci_hw_rd_conf(u32 bus, u32 dev, u32 func, u32 where, u32 size, u32 *val);
 int orion_pci_hw_wr_conf(u32 bus, u32 dev, u32 func, u32 where, u32 size, u32 val);
 
+/*
+ * Valid GPIO pins according to MPP setup, used by machine-setup.
+ * (/mach-orion/gpio.c).
+ */
+
+void __init orion_gpio_set_valid_pins(u32 pins);
+void gpio_display(void);	/* debug */
+
 #endif /* __ARCH_ORION_COMMON_H__ */

arch/arm/mach-orion/gpio.c

+/*
+ * 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;
+	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);
+	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);
+
+	if (value)
+		orion_setbits(GPIO_OUT, mask);
+	else
+		orion_clrbits(GPIO_OUT, mask);
+
+	spin_unlock_irqrestore(&gpio_lock, flags);
+}
+EXPORT_SYMBOL(gpio_set_value);
+
+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));
+}

include/asm-arm/arch-orion/gpio.h

+/*
+ * include/asm-arm/arch-orion/gpio.h
+ *
+ * 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.
+ */
+
+extern int gpio_request(unsigned pin, const char *label);
+extern void gpio_free(unsigned pin);
+extern int gpio_direction_input(unsigned pin);
+extern int gpio_direction_output(unsigned pin, int value);
+extern int gpio_get_value(unsigned pin);
+extern void gpio_set_value(unsigned pin, int value);
+extern void gpio_display(void);		/* debug */
+
+static inline int gpio_to_irq(int pin)
+{
+	return pin + IRQ_ORION_GPIO_START;
+}
+
+static inline int irq_to_gpio(int irq)
+{
+	return irq - IRQ_ORION_GPIO_START;
+}
+
+#include <asm-generic/gpio.h>		/* cansleep wrappers */