--- /dev/null
+/*
+ * 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");
+
+
projects / GitHub / MotorolaMobilityLLC / kernel-slsi.git / commitdiff