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");
+
+