1 files changed, 435 insertions, 0 deletions

diff --git a/arch/arm/plat-nomadik/gpio.c b/arch/arm/plat-nomadik/gpio.c
new file mode 100644
index 00000000000..5a6ef252c38
--- /dev/null
+++ b/arch/arm/plat-nomadik/gpio.c
@@ -0,0 +1,435 @@
+/*
+ * Generic GPIO driver for logic cells found in the Nomadik SoC
+ *
+ * Copyright (C) 2008,2009 STMicroelectronics
+ * Copyright (C) 2009 Alessandro Rubini <rubini@unipv.it>
+ *   Rewritten based on work by Prafulla WADASKAR <prafulla.wadaskar@st.com>
+ *
+ * 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.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+
+#include <mach/hardware.h>
+#include <mach/gpio.h>
+
+/*
+ * The GPIO module in the Nomadik family of Systems-on-Chip is an
+ * AMBA device, managing 32 pins and alternate functions.  The logic block
+ * is currently only used in the Nomadik.
+ *
+ * Symbols in this file are called "nmk_gpio" for "nomadik gpio"
+ */
+
+#define NMK_GPIO_PER_CHIP 32
+struct nmk_gpio_chip {
+	struct gpio_chip chip;
+	void __iomem *addr;
+	struct clk *clk;
+	unsigned int parent_irq;
+	spinlock_t lock;
+	/* Keep track of configured edges */
+	u32 edge_rising;
+	u32 edge_falling;
+};
+
+/* Mode functions */
+int nmk_gpio_set_mode(int gpio, int gpio_mode)
+{
+	struct nmk_gpio_chip *nmk_chip;
+	unsigned long flags;
+	u32 afunc, bfunc, bit;
+
+	nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
+	if (!nmk_chip)
+		return -EINVAL;
+
+	bit = 1 << (gpio - nmk_chip->chip.base);
+
+	spin_lock_irqsave(&nmk_chip->lock, flags);
+	afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & ~bit;
+	bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & ~bit;
+	if (gpio_mode & NMK_GPIO_ALT_A)
+		afunc |= bit;
+	if (gpio_mode & NMK_GPIO_ALT_B)
+		bfunc |= bit;
+	writel(afunc, nmk_chip->addr + NMK_GPIO_AFSLA);
+	writel(bfunc, nmk_chip->addr + NMK_GPIO_AFSLB);
+	spin_unlock_irqrestore(&nmk_chip->lock, flags);
+
+	return 0;
+}
+EXPORT_SYMBOL(nmk_gpio_set_mode);
+
+int nmk_gpio_get_mode(int gpio)
+{
+	struct nmk_gpio_chip *nmk_chip;
+	u32 afunc, bfunc, bit;
+
+	nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
+	if (!nmk_chip)
+		return -EINVAL;
+
+	bit = 1 << (gpio - nmk_chip->chip.base);
+
+	afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & bit;
+	bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & bit;
+
+	return (afunc ? NMK_GPIO_ALT_A : 0) | (bfunc ? NMK_GPIO_ALT_B : 0);
+}
+EXPORT_SYMBOL(nmk_gpio_get_mode);
+
+
+/* IRQ functions */
+static inline int nmk_gpio_get_bitmask(int gpio)
+{
+	return 1 << (gpio % 32);
+}
+
+static void nmk_gpio_irq_ack(unsigned int irq)
+{
+	int gpio;
+	struct nmk_gpio_chip *nmk_chip;
+
+	gpio = NOMADIK_IRQ_TO_GPIO(irq);
+	nmk_chip = get_irq_chip_data(irq);
+	if (!nmk_chip)
+		return;
+	writel(nmk_gpio_get_bitmask(gpio), nmk_chip->addr + NMK_GPIO_IC);
+}
+
+static void __nmk_gpio_irq_modify(struct nmk_gpio_chip *nmk_chip,
+				  int gpio, bool enable)
+{
+	u32 bitmask = nmk_gpio_get_bitmask(gpio);
+	u32 reg;
+
+	/* we must individually set/clear the two edges */
+	if (nmk_chip->edge_rising & bitmask) {
+		reg = readl(nmk_chip->addr + NMK_GPIO_RIMSC);
+		if (enable)
+			reg |= bitmask;
+		else
+			reg &= ~bitmask;
+		writel(reg, nmk_chip->addr + NMK_GPIO_RIMSC);
+	}
+	if (nmk_chip->edge_falling & bitmask) {
+		reg = readl(nmk_chip->addr + NMK_GPIO_FIMSC);
+		if (enable)
+			reg |= bitmask;
+		else
+			reg &= ~bitmask;
+		writel(reg, nmk_chip->addr + NMK_GPIO_FIMSC);
+	}
+}
+
+static void nmk_gpio_irq_modify(unsigned int irq, bool enable)
+{
+	int gpio;
+	struct nmk_gpio_chip *nmk_chip;
+	unsigned long flags;
+	u32 bitmask;
+
+	gpio = NOMADIK_IRQ_TO_GPIO(irq);
+	nmk_chip = get_irq_chip_data(irq);
+	bitmask = nmk_gpio_get_bitmask(gpio);
+	if (!nmk_chip)
+		return;
+
+	spin_lock_irqsave(&nmk_chip->lock, flags);
+	__nmk_gpio_irq_modify(nmk_chip, gpio, enable);
+	spin_unlock_irqrestore(&nmk_chip->lock, flags);
+}
+
+static void nmk_gpio_irq_mask(unsigned int irq)
+{
+	nmk_gpio_irq_modify(irq, false);
+};
+
+static void nmk_gpio_irq_unmask(unsigned int irq)
+{
+	nmk_gpio_irq_modify(irq, true);
+}
+
+static int nmk_gpio_irq_set_type(unsigned int irq, unsigned int type)
+{
+	bool enabled = !(irq_to_desc(irq)->status & IRQ_DISABLED);
+	int gpio;
+	struct nmk_gpio_chip *nmk_chip;
+	unsigned long flags;
+	u32 bitmask;
+
+	gpio = NOMADIK_IRQ_TO_GPIO(irq);
+	nmk_chip = get_irq_chip_data(irq);
+	bitmask = nmk_gpio_get_bitmask(gpio);
+	if (!nmk_chip)
+		return -EINVAL;
+
+	if (type & IRQ_TYPE_LEVEL_HIGH)
+		return -EINVAL;
+	if (type & IRQ_TYPE_LEVEL_LOW)
+		return -EINVAL;
+
+	spin_lock_irqsave(&nmk_chip->lock, flags);
+
+	if (enabled)
+		__nmk_gpio_irq_modify(nmk_chip, gpio, false);
+
+	nmk_chip->edge_rising &= ~bitmask;
+	if (type & IRQ_TYPE_EDGE_RISING)
+		nmk_chip->edge_rising |= bitmask;
+
+	nmk_chip->edge_falling &= ~bitmask;
+	if (type & IRQ_TYPE_EDGE_FALLING)
+		nmk_chip->edge_falling |= bitmask;
+
+	if (enabled)
+		__nmk_gpio_irq_modify(nmk_chip, gpio, true);
+
+	spin_unlock_irqrestore(&nmk_chip->lock, flags);
+
+	return 0;
+}
+
+static struct irq_chip nmk_gpio_irq_chip = {
+	.name		= "Nomadik-GPIO",
+	.ack		= nmk_gpio_irq_ack,
+	.mask		= nmk_gpio_irq_mask,
+	.unmask		= nmk_gpio_irq_unmask,
+	.set_type	= nmk_gpio_irq_set_type,
+};
+
+static void nmk_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+	struct nmk_gpio_chip *nmk_chip;
+	struct irq_chip *host_chip = get_irq_chip(irq);
+	unsigned int gpio_irq;
+	u32 pending;
+	unsigned int first_irq;
+
+	if (host_chip->mask_ack)
+		host_chip->mask_ack(irq);
+	else {
+		host_chip->mask(irq);
+		if (host_chip->ack)
+			host_chip->ack(irq);
+	}
+
+	nmk_chip = get_irq_data(irq);
+	first_irq = NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base);
+	while ( (pending = readl(nmk_chip->addr + NMK_GPIO_IS)) ) {
+		gpio_irq = first_irq + __ffs(pending);
+		generic_handle_irq(gpio_irq);
+	}
+
+	host_chip->unmask(irq);
+}
+
+static int nmk_gpio_init_irq(struct nmk_gpio_chip *nmk_chip)
+{
+	unsigned int first_irq;
+	int i;
+
+	first_irq = NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base);
+	for (i = first_irq; i < first_irq + NMK_GPIO_PER_CHIP; i++) {
+		set_irq_chip(i, &nmk_gpio_irq_chip);
+		set_irq_handler(i, handle_edge_irq);
+		set_irq_flags(i, IRQF_VALID);
+		set_irq_chip_data(i, nmk_chip);
+		set_irq_type(i, IRQ_TYPE_EDGE_FALLING);
+	}
+	set_irq_chained_handler(nmk_chip->parent_irq, nmk_gpio_irq_handler);
+	set_irq_data(nmk_chip->parent_irq, nmk_chip);
+	return 0;
+}
+
+/* I/O Functions */
+static int nmk_gpio_make_input(struct gpio_chip *chip, unsigned offset)
+{
+	struct nmk_gpio_chip *nmk_chip =
+		container_of(chip, struct nmk_gpio_chip, chip);
+
+	writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRC);
+	return 0;
+}
+
+static int nmk_gpio_make_output(struct gpio_chip *chip, unsigned offset,
+				int val)
+{
+	struct nmk_gpio_chip *nmk_chip =
+		container_of(chip, struct nmk_gpio_chip, chip);
+
+	writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRS);
+	return 0;
+}
+
+static int nmk_gpio_get_input(struct gpio_chip *chip, unsigned offset)
+{
+	struct nmk_gpio_chip *nmk_chip =
+		container_of(chip, struct nmk_gpio_chip, chip);
+	u32 bit = 1 << offset;
+
+	return (readl(nmk_chip->addr + NMK_GPIO_DAT) & bit) != 0;
+}
+
+static void nmk_gpio_set_output(struct gpio_chip *chip, unsigned offset,
+				int val)
+{
+	struct nmk_gpio_chip *nmk_chip =
+		container_of(chip, struct nmk_gpio_chip, chip);
+	u32 bit = 1 << offset;
+
+	if (val)
+		writel(bit, nmk_chip->addr + NMK_GPIO_DATS);
+	else
+		writel(bit, nmk_chip->addr + NMK_GPIO_DATC);
+}
+
+/* This structure is replicated for each GPIO block allocated at probe time */
+static struct gpio_chip nmk_gpio_template = {
+	.direction_input	= nmk_gpio_make_input,
+	.get			= nmk_gpio_get_input,
+	.direction_output	= nmk_gpio_make_output,
+	.set			= nmk_gpio_set_output,
+	.ngpio			= NMK_GPIO_PER_CHIP,
+	.can_sleep		= 0,
+};
+
+static int __init nmk_gpio_probe(struct platform_device *dev)
+{
+	struct nmk_gpio_platform_data *pdata = dev->dev.platform_data;
+	struct nmk_gpio_chip *nmk_chip;
+	struct gpio_chip *chip;
+	struct resource *res;
+	struct clk *clk;
+	int irq;
+	int ret;
+
+	if (!pdata)
+		return -ENODEV;
+
+	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+	if (!res) {
+		ret = -ENOENT;
+		goto out;
+	}
+
+	irq = platform_get_irq(dev, 0);
+	if (irq < 0) {
+		ret = irq;
+		goto out;
+	}
+
+	if (request_mem_region(res->start, resource_size(res),
+			       dev_name(&dev->dev)) == NULL) {
+		ret = -EBUSY;
+		goto out;
+	}
+
+	clk = clk_get(&dev->dev, NULL);
+	if (IS_ERR(clk)) {
+		ret = PTR_ERR(clk);
+		goto out_release;
+	}
+
+	clk_enable(clk);
+
+	nmk_chip = kzalloc(sizeof(*nmk_chip), GFP_KERNEL);
+	if (!nmk_chip) {
+		ret = -ENOMEM;
+		goto out_clk;
+	}
+	/*
+	 * The virt address in nmk_chip->addr is in the nomadik register space,
+	 * so we can simply convert the resource address, without remapping
+	 */
+	nmk_chip->clk = clk;
+	nmk_chip->addr = io_p2v(res->start);
+	nmk_chip->chip = nmk_gpio_template;
+	nmk_chip->parent_irq = irq;
+	spin_lock_init(&nmk_chip->lock);
+
+	chip = &nmk_chip->chip;
+	chip->base = pdata->first_gpio;
+	chip->label = pdata->name;
+	chip->dev = &dev->dev;
+	chip->owner = THIS_MODULE;
+
+	ret = gpiochip_add(&nmk_chip->chip);
+	if (ret)
+		goto out_free;
+
+	platform_set_drvdata(dev, nmk_chip);
+
+	nmk_gpio_init_irq(nmk_chip);
+
+	dev_info(&dev->dev, "Bits %i-%i at address %p\n",
+		 nmk_chip->chip.base, nmk_chip->chip.base+31, nmk_chip->addr);
+	return 0;
+
+out_free:
+	kfree(nmk_chip);
+out_clk:
+	clk_disable(clk);
+	clk_put(clk);
+out_release:
+	release_mem_region(res->start, resource_size(res));
+out:
+	dev_err(&dev->dev, "Failure %i for GPIO %i-%i\n", ret,
+		  pdata->first_gpio, pdata->first_gpio+31);
+	return ret;
+}
+
+static int __exit nmk_gpio_remove(struct platform_device *dev)
+{
+	struct nmk_gpio_chip *nmk_chip;
+	struct resource *res;
+
+	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+
+	nmk_chip = platform_get_drvdata(dev);
+	gpiochip_remove(&nmk_chip->chip);
+	clk_disable(nmk_chip->clk);
+	clk_put(nmk_chip->clk);
+	kfree(nmk_chip);
+	release_mem_region(res->start, resource_size(res));
+	return 0;
+}
+
+
+static struct platform_driver nmk_gpio_driver = {
+	.driver = {
+		.owner = THIS_MODULE,
+		.name = "gpio",
+		},
+	.probe = nmk_gpio_probe,
+	.remove = __exit_p(nmk_gpio_remove),
+	.suspend = NULL, /* to be done */
+	.resume = NULL,
+};
+
+static int __init nmk_gpio_init(void)
+{
+	return platform_driver_register(&nmk_gpio_driver);
+}
+
+arch_initcall(nmk_gpio_init);
+
+MODULE_AUTHOR("Prafulla WADASKAR and Alessandro Rubini");
+MODULE_DESCRIPTION("Nomadik GPIO Driver");
+MODULE_LICENSE("GPL");
+
+