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path: root/kernel/drivers/gpio/gpio-pl061.c
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Diffstat (limited to 'kernel/drivers/gpio/gpio-pl061.c')
-rw-r--r--kernel/drivers/gpio/gpio-pl061.c408
1 files changed, 408 insertions, 0 deletions
diff --git a/kernel/drivers/gpio/gpio-pl061.c b/kernel/drivers/gpio/gpio-pl061.c
new file mode 100644
index 000000000..047561304
--- /dev/null
+++ b/kernel/drivers/gpio/gpio-pl061.c
@@ -0,0 +1,408 @@
+/*
+ * Copyright (C) 2008, 2009 Provigent Ltd.
+ *
+ * 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.
+ *
+ * Driver for the ARM PrimeCell(tm) General Purpose Input/Output (PL061)
+ *
+ * Data sheet: ARM DDI 0190B, September 2000
+ */
+#include <linux/spinlock.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/bitops.h>
+#include <linux/gpio.h>
+#include <linux/device.h>
+#include <linux/amba/bus.h>
+#include <linux/amba/pl061.h>
+#include <linux/slab.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/pm.h>
+
+#define GPIODIR 0x400
+#define GPIOIS 0x404
+#define GPIOIBE 0x408
+#define GPIOIEV 0x40C
+#define GPIOIE 0x410
+#define GPIORIS 0x414
+#define GPIOMIS 0x418
+#define GPIOIC 0x41C
+
+#define PL061_GPIO_NR 8
+
+#ifdef CONFIG_PM
+struct pl061_context_save_regs {
+ u8 gpio_data;
+ u8 gpio_dir;
+ u8 gpio_is;
+ u8 gpio_ibe;
+ u8 gpio_iev;
+ u8 gpio_ie;
+};
+#endif
+
+struct pl061_gpio {
+ spinlock_t lock;
+
+ void __iomem *base;
+ struct gpio_chip gc;
+ bool uses_pinctrl;
+
+#ifdef CONFIG_PM
+ struct pl061_context_save_regs csave_regs;
+#endif
+};
+
+static int pl061_gpio_request(struct gpio_chip *gc, unsigned offset)
+{
+ /*
+ * Map back to global GPIO space and request muxing, the direction
+ * parameter does not matter for this controller.
+ */
+ struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
+ int gpio = gc->base + offset;
+
+ if (chip->uses_pinctrl)
+ return pinctrl_request_gpio(gpio);
+ return 0;
+}
+
+static void pl061_gpio_free(struct gpio_chip *gc, unsigned offset)
+{
+ struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
+ int gpio = gc->base + offset;
+
+ if (chip->uses_pinctrl)
+ pinctrl_free_gpio(gpio);
+}
+
+static int pl061_direction_input(struct gpio_chip *gc, unsigned offset)
+{
+ struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
+ unsigned long flags;
+ unsigned char gpiodir;
+
+ if (offset >= gc->ngpio)
+ return -EINVAL;
+
+ spin_lock_irqsave(&chip->lock, flags);
+ gpiodir = readb(chip->base + GPIODIR);
+ gpiodir &= ~(BIT(offset));
+ writeb(gpiodir, chip->base + GPIODIR);
+ spin_unlock_irqrestore(&chip->lock, flags);
+
+ return 0;
+}
+
+static int pl061_direction_output(struct gpio_chip *gc, unsigned offset,
+ int value)
+{
+ struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
+ unsigned long flags;
+ unsigned char gpiodir;
+
+ if (offset >= gc->ngpio)
+ return -EINVAL;
+
+ spin_lock_irqsave(&chip->lock, flags);
+ writeb(!!value << offset, chip->base + (BIT(offset + 2)));
+ gpiodir = readb(chip->base + GPIODIR);
+ gpiodir |= BIT(offset);
+ writeb(gpiodir, chip->base + GPIODIR);
+
+ /*
+ * gpio value is set again, because pl061 doesn't allow to set value of
+ * a gpio pin before configuring it in OUT mode.
+ */
+ writeb(!!value << offset, chip->base + (BIT(offset + 2)));
+ spin_unlock_irqrestore(&chip->lock, flags);
+
+ return 0;
+}
+
+static int pl061_get_value(struct gpio_chip *gc, unsigned offset)
+{
+ struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
+
+ return !!readb(chip->base + (BIT(offset + 2)));
+}
+
+static void pl061_set_value(struct gpio_chip *gc, unsigned offset, int value)
+{
+ struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
+
+ writeb(!!value << offset, chip->base + (BIT(offset + 2)));
+}
+
+static int pl061_irq_type(struct irq_data *d, unsigned trigger)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
+ int offset = irqd_to_hwirq(d);
+ unsigned long flags;
+ u8 gpiois, gpioibe, gpioiev;
+ u8 bit = BIT(offset);
+
+ if (offset < 0 || offset >= PL061_GPIO_NR)
+ return -EINVAL;
+
+ spin_lock_irqsave(&chip->lock, flags);
+
+ gpioiev = readb(chip->base + GPIOIEV);
+ gpiois = readb(chip->base + GPIOIS);
+ gpioibe = readb(chip->base + GPIOIBE);
+
+ if (trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) {
+ gpiois |= bit;
+ if (trigger & IRQ_TYPE_LEVEL_HIGH)
+ gpioiev |= bit;
+ else
+ gpioiev &= ~bit;
+ } else
+ gpiois &= ~bit;
+
+ if ((trigger & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH)
+ /* Setting this makes GPIOEV be ignored */
+ gpioibe |= bit;
+ else {
+ gpioibe &= ~bit;
+ if (trigger & IRQ_TYPE_EDGE_RISING)
+ gpioiev |= bit;
+ else if (trigger & IRQ_TYPE_EDGE_FALLING)
+ gpioiev &= ~bit;
+ }
+
+ writeb(gpiois, chip->base + GPIOIS);
+ writeb(gpioibe, chip->base + GPIOIBE);
+ writeb(gpioiev, chip->base + GPIOIEV);
+
+ spin_unlock_irqrestore(&chip->lock, flags);
+
+ return 0;
+}
+
+static void pl061_irq_handler(unsigned irq, struct irq_desc *desc)
+{
+ unsigned long pending;
+ int offset;
+ struct gpio_chip *gc = irq_desc_get_handler_data(desc);
+ struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
+ struct irq_chip *irqchip = irq_desc_get_chip(desc);
+
+ chained_irq_enter(irqchip, desc);
+
+ pending = readb(chip->base + GPIOMIS);
+ writeb(pending, chip->base + GPIOIC);
+ if (pending) {
+ for_each_set_bit(offset, &pending, PL061_GPIO_NR)
+ generic_handle_irq(irq_find_mapping(gc->irqdomain,
+ offset));
+ }
+
+ chained_irq_exit(irqchip, desc);
+}
+
+static void pl061_irq_mask(struct irq_data *d)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
+ u8 mask = BIT(irqd_to_hwirq(d) % PL061_GPIO_NR);
+ u8 gpioie;
+
+ spin_lock(&chip->lock);
+ gpioie = readb(chip->base + GPIOIE) & ~mask;
+ writeb(gpioie, chip->base + GPIOIE);
+ spin_unlock(&chip->lock);
+}
+
+static void pl061_irq_unmask(struct irq_data *d)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
+ u8 mask = BIT(irqd_to_hwirq(d) % PL061_GPIO_NR);
+ u8 gpioie;
+
+ spin_lock(&chip->lock);
+ gpioie = readb(chip->base + GPIOIE) | mask;
+ writeb(gpioie, chip->base + GPIOIE);
+ spin_unlock(&chip->lock);
+}
+
+static struct irq_chip pl061_irqchip = {
+ .name = "pl061",
+ .irq_mask = pl061_irq_mask,
+ .irq_unmask = pl061_irq_unmask,
+ .irq_set_type = pl061_irq_type,
+};
+
+static int pl061_probe(struct amba_device *adev, const struct amba_id *id)
+{
+ struct device *dev = &adev->dev;
+ struct pl061_platform_data *pdata = dev_get_platdata(dev);
+ struct pl061_gpio *chip;
+ int ret, irq, i, irq_base;
+
+ chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
+ if (chip == NULL)
+ return -ENOMEM;
+
+ if (pdata) {
+ chip->gc.base = pdata->gpio_base;
+ irq_base = pdata->irq_base;
+ if (irq_base <= 0) {
+ dev_err(&adev->dev, "invalid IRQ base in pdata\n");
+ return -ENODEV;
+ }
+ } else {
+ chip->gc.base = -1;
+ irq_base = 0;
+ }
+
+ chip->base = devm_ioremap_resource(dev, &adev->res);
+ if (IS_ERR(chip->base))
+ return PTR_ERR(chip->base);
+
+ spin_lock_init(&chip->lock);
+ if (of_property_read_bool(dev->of_node, "gpio-ranges"))
+ chip->uses_pinctrl = true;
+
+ chip->gc.request = pl061_gpio_request;
+ chip->gc.free = pl061_gpio_free;
+ chip->gc.direction_input = pl061_direction_input;
+ chip->gc.direction_output = pl061_direction_output;
+ chip->gc.get = pl061_get_value;
+ chip->gc.set = pl061_set_value;
+ chip->gc.ngpio = PL061_GPIO_NR;
+ chip->gc.label = dev_name(dev);
+ chip->gc.dev = dev;
+ chip->gc.owner = THIS_MODULE;
+
+ ret = gpiochip_add(&chip->gc);
+ if (ret)
+ return ret;
+
+ /*
+ * irq_chip support
+ */
+ writeb(0, chip->base + GPIOIE); /* disable irqs */
+ irq = adev->irq[0];
+ if (irq < 0) {
+ dev_err(&adev->dev, "invalid IRQ\n");
+ return -ENODEV;
+ }
+
+ ret = gpiochip_irqchip_add(&chip->gc, &pl061_irqchip,
+ irq_base, handle_simple_irq,
+ IRQ_TYPE_NONE);
+ if (ret) {
+ dev_info(&adev->dev, "could not add irqchip\n");
+ return ret;
+ }
+ gpiochip_set_chained_irqchip(&chip->gc, &pl061_irqchip,
+ irq, pl061_irq_handler);
+
+ for (i = 0; i < PL061_GPIO_NR; i++) {
+ if (pdata) {
+ if (pdata->directions & (BIT(i)))
+ pl061_direction_output(&chip->gc, i,
+ pdata->values & (BIT(i)));
+ else
+ pl061_direction_input(&chip->gc, i);
+ }
+ }
+
+ amba_set_drvdata(adev, chip);
+ dev_info(&adev->dev, "PL061 GPIO chip @%pa registered\n",
+ &adev->res.start);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int pl061_suspend(struct device *dev)
+{
+ struct pl061_gpio *chip = dev_get_drvdata(dev);
+ int offset;
+
+ chip->csave_regs.gpio_data = 0;
+ chip->csave_regs.gpio_dir = readb(chip->base + GPIODIR);
+ chip->csave_regs.gpio_is = readb(chip->base + GPIOIS);
+ chip->csave_regs.gpio_ibe = readb(chip->base + GPIOIBE);
+ chip->csave_regs.gpio_iev = readb(chip->base + GPIOIEV);
+ chip->csave_regs.gpio_ie = readb(chip->base + GPIOIE);
+
+ for (offset = 0; offset < PL061_GPIO_NR; offset++) {
+ if (chip->csave_regs.gpio_dir & (BIT(offset)))
+ chip->csave_regs.gpio_data |=
+ pl061_get_value(&chip->gc, offset) << offset;
+ }
+
+ return 0;
+}
+
+static int pl061_resume(struct device *dev)
+{
+ struct pl061_gpio *chip = dev_get_drvdata(dev);
+ int offset;
+
+ for (offset = 0; offset < PL061_GPIO_NR; offset++) {
+ if (chip->csave_regs.gpio_dir & (BIT(offset)))
+ pl061_direction_output(&chip->gc, offset,
+ chip->csave_regs.gpio_data &
+ (BIT(offset)));
+ else
+ pl061_direction_input(&chip->gc, offset);
+ }
+
+ writeb(chip->csave_regs.gpio_is, chip->base + GPIOIS);
+ writeb(chip->csave_regs.gpio_ibe, chip->base + GPIOIBE);
+ writeb(chip->csave_regs.gpio_iev, chip->base + GPIOIEV);
+ writeb(chip->csave_regs.gpio_ie, chip->base + GPIOIE);
+
+ return 0;
+}
+
+static const struct dev_pm_ops pl061_dev_pm_ops = {
+ .suspend = pl061_suspend,
+ .resume = pl061_resume,
+ .freeze = pl061_suspend,
+ .restore = pl061_resume,
+};
+#endif
+
+static struct amba_id pl061_ids[] = {
+ {
+ .id = 0x00041061,
+ .mask = 0x000fffff,
+ },
+ { 0, 0 },
+};
+
+MODULE_DEVICE_TABLE(amba, pl061_ids);
+
+static struct amba_driver pl061_gpio_driver = {
+ .drv = {
+ .name = "pl061_gpio",
+#ifdef CONFIG_PM
+ .pm = &pl061_dev_pm_ops,
+#endif
+ },
+ .id_table = pl061_ids,
+ .probe = pl061_probe,
+};
+
+static int __init pl061_gpio_init(void)
+{
+ return amba_driver_register(&pl061_gpio_driver);
+}
+module_init(pl061_gpio_init);
+
+MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
+MODULE_DESCRIPTION("PL061 GPIO driver");
+MODULE_LICENSE("GPL");