Initial import

1 files changed, 346 insertions, 0 deletions

diff --git a/drivers/gpio/gpio-timberdale.c b/drivers/gpio/gpio-timberdale.c
new file mode 100644
index 000000000..e8f97e03c
--- /dev/null
+++ b/drivers/gpio/gpio-timberdale.c
@@ -0,0 +1,346 @@
+/*
+ * Timberdale FPGA GPIO driver
+ * Copyright (c) 2009 Intel Corporation
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+/* Supports:
+ * Timberdale FPGA GPIO
+ */
+
+#include <linux/module.h>
+#include <linux/gpio.h>
+#include <linux/platform_device.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/timb_gpio.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+
+#define DRIVER_NAME "timb-gpio"
+
+#define TGPIOVAL	0x00
+#define TGPIODIR	0x04
+#define TGPIO_IER	0x08
+#define TGPIO_ISR	0x0c
+#define TGPIO_IPR	0x10
+#define TGPIO_ICR	0x14
+#define TGPIO_FLR	0x18
+#define TGPIO_LVR	0x1c
+#define TGPIO_VER	0x20
+#define TGPIO_BFLR	0x24
+
+struct timbgpio {
+	void __iomem		*membase;
+	spinlock_t		lock; /* mutual exclusion */
+	struct gpio_chip	gpio;
+	int			irq_base;
+	unsigned long		last_ier;
+};
+
+static int timbgpio_update_bit(struct gpio_chip *gpio, unsigned index,
+	unsigned offset, bool enabled)
+{
+	struct timbgpio *tgpio = container_of(gpio, struct timbgpio, gpio);
+	u32 reg;
+
+	spin_lock(&tgpio->lock);
+	reg = ioread32(tgpio->membase + offset);
+
+	if (enabled)
+		reg |= (1 << index);
+	else
+		reg &= ~(1 << index);
+
+	iowrite32(reg, tgpio->membase + offset);
+	spin_unlock(&tgpio->lock);
+
+	return 0;
+}
+
+static int timbgpio_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
+{
+	return timbgpio_update_bit(gpio, nr, TGPIODIR, true);
+}
+
+static int timbgpio_gpio_get(struct gpio_chip *gpio, unsigned nr)
+{
+	struct timbgpio *tgpio = container_of(gpio, struct timbgpio, gpio);
+	u32 value;
+
+	value = ioread32(tgpio->membase + TGPIOVAL);
+	return (value & (1 << nr)) ? 1 : 0;
+}
+
+static int timbgpio_gpio_direction_output(struct gpio_chip *gpio,
+						unsigned nr, int val)
+{
+	return timbgpio_update_bit(gpio, nr, TGPIODIR, false);
+}
+
+static void timbgpio_gpio_set(struct gpio_chip *gpio,
+				unsigned nr, int val)
+{
+	timbgpio_update_bit(gpio, nr, TGPIOVAL, val != 0);
+}
+
+static int timbgpio_to_irq(struct gpio_chip *gpio, unsigned offset)
+{
+	struct timbgpio *tgpio = container_of(gpio, struct timbgpio, gpio);
+
+	if (tgpio->irq_base <= 0)
+		return -EINVAL;
+
+	return tgpio->irq_base + offset;
+}
+
+/*
+ * GPIO IRQ
+ */
+static void timbgpio_irq_disable(struct irq_data *d)
+{
+	struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
+	int offset = d->irq - tgpio->irq_base;
+	unsigned long flags;
+
+	spin_lock_irqsave(&tgpio->lock, flags);
+	tgpio->last_ier &= ~(1UL << offset);
+	iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
+	spin_unlock_irqrestore(&tgpio->lock, flags);
+}
+
+static void timbgpio_irq_enable(struct irq_data *d)
+{
+	struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
+	int offset = d->irq - tgpio->irq_base;
+	unsigned long flags;
+
+	spin_lock_irqsave(&tgpio->lock, flags);
+	tgpio->last_ier |= 1UL << offset;
+	iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
+	spin_unlock_irqrestore(&tgpio->lock, flags);
+}
+
+static int timbgpio_irq_type(struct irq_data *d, unsigned trigger)
+{
+	struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
+	int offset = d->irq - tgpio->irq_base;
+	unsigned long flags;
+	u32 lvr, flr, bflr = 0;
+	u32 ver;
+	int ret = 0;
+
+	if (offset < 0 || offset > tgpio->gpio.ngpio)
+		return -EINVAL;
+
+	ver = ioread32(tgpio->membase + TGPIO_VER);
+
+	spin_lock_irqsave(&tgpio->lock, flags);
+
+	lvr = ioread32(tgpio->membase + TGPIO_LVR);
+	flr = ioread32(tgpio->membase + TGPIO_FLR);
+	if (ver > 2)
+		bflr = ioread32(tgpio->membase + TGPIO_BFLR);
+
+	if (trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) {
+		bflr &= ~(1 << offset);
+		flr &= ~(1 << offset);
+		if (trigger & IRQ_TYPE_LEVEL_HIGH)
+			lvr |= 1 << offset;
+		else
+			lvr &= ~(1 << offset);
+	}
+
+	if ((trigger & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
+		if (ver < 3) {
+			ret = -EINVAL;
+			goto out;
+		} else {
+			flr |= 1 << offset;
+			bflr |= 1 << offset;
+		}
+	} else {
+		bflr &= ~(1 << offset);
+		flr |= 1 << offset;
+		if (trigger & IRQ_TYPE_EDGE_FALLING)
+			lvr &= ~(1 << offset);
+		else
+			lvr |= 1 << offset;
+	}
+
+	iowrite32(lvr, tgpio->membase + TGPIO_LVR);
+	iowrite32(flr, tgpio->membase + TGPIO_FLR);
+	if (ver > 2)
+		iowrite32(bflr, tgpio->membase + TGPIO_BFLR);
+
+	iowrite32(1 << offset, tgpio->membase + TGPIO_ICR);
+
+out:
+	spin_unlock_irqrestore(&tgpio->lock, flags);
+	return ret;
+}
+
+static void timbgpio_irq(unsigned int irq, struct irq_desc *desc)
+{
+	struct timbgpio *tgpio = irq_get_handler_data(irq);
+	unsigned long ipr;
+	int offset;
+
+	desc->irq_data.chip->irq_ack(irq_get_irq_data(irq));
+	ipr = ioread32(tgpio->membase + TGPIO_IPR);
+	iowrite32(ipr, tgpio->membase + TGPIO_ICR);
+
+	/*
+	 * Some versions of the hardware trash the IER register if more than
+	 * one interrupt is received simultaneously.
+	 */
+	iowrite32(0, tgpio->membase + TGPIO_IER);
+
+	for_each_set_bit(offset, &ipr, tgpio->gpio.ngpio)
+		generic_handle_irq(timbgpio_to_irq(&tgpio->gpio, offset));
+
+	iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
+}
+
+static struct irq_chip timbgpio_irqchip = {
+	.name		= "GPIO",
+	.irq_enable	= timbgpio_irq_enable,
+	.irq_disable	= timbgpio_irq_disable,
+	.irq_set_type	= timbgpio_irq_type,
+};
+
+static int timbgpio_probe(struct platform_device *pdev)
+{
+	int err, i;
+	struct device *dev = &pdev->dev;
+	struct gpio_chip *gc;
+	struct timbgpio *tgpio;
+	struct resource *iomem;
+	struct timbgpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
+	int irq = platform_get_irq(pdev, 0);
+
+	if (!pdata || pdata->nr_pins > 32) {
+		dev_err(dev, "Invalid platform data\n");
+		return -EINVAL;
+	}
+
+	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!iomem) {
+		dev_err(dev, "Unable to get resource\n");
+		return -EINVAL;
+	}
+
+	tgpio = devm_kzalloc(dev, sizeof(struct timbgpio), GFP_KERNEL);
+	if (!tgpio) {
+		dev_err(dev, "Memory alloc failed\n");
+		return -EINVAL;
+	}
+	tgpio->irq_base = pdata->irq_base;
+
+	spin_lock_init(&tgpio->lock);
+
+	if (!devm_request_mem_region(dev, iomem->start, resource_size(iomem),
+				     DRIVER_NAME)) {
+		dev_err(dev, "Region already claimed\n");
+		return -EBUSY;
+	}
+
+	tgpio->membase = devm_ioremap(dev, iomem->start, resource_size(iomem));
+	if (!tgpio->membase) {
+		dev_err(dev, "Cannot ioremap\n");
+		return -ENOMEM;
+	}
+
+	gc = &tgpio->gpio;
+
+	gc->label = dev_name(&pdev->dev);
+	gc->owner = THIS_MODULE;
+	gc->dev = &pdev->dev;
+	gc->direction_input = timbgpio_gpio_direction_input;
+	gc->get = timbgpio_gpio_get;
+	gc->direction_output = timbgpio_gpio_direction_output;
+	gc->set = timbgpio_gpio_set;
+	gc->to_irq = (irq >= 0 && tgpio->irq_base > 0) ? timbgpio_to_irq : NULL;
+	gc->dbg_show = NULL;
+	gc->base = pdata->gpio_base;
+	gc->ngpio = pdata->nr_pins;
+	gc->can_sleep = false;
+
+	err = gpiochip_add(gc);
+	if (err)
+		return err;
+
+	platform_set_drvdata(pdev, tgpio);
+
+	/* make sure to disable interrupts */
+	iowrite32(0x0, tgpio->membase + TGPIO_IER);
+
+	if (irq < 0 || tgpio->irq_base <= 0)
+		return 0;
+
+	for (i = 0; i < pdata->nr_pins; i++) {
+		irq_set_chip_and_handler(tgpio->irq_base + i,
+			&timbgpio_irqchip, handle_simple_irq);
+		irq_set_chip_data(tgpio->irq_base + i, tgpio);
+#ifdef CONFIG_ARM
+		set_irq_flags(tgpio->irq_base + i, IRQF_VALID | IRQF_PROBE);
+#endif
+	}
+
+	irq_set_handler_data(irq, tgpio);
+	irq_set_chained_handler(irq, timbgpio_irq);
+
+	return 0;
+}
+
+static int timbgpio_remove(struct platform_device *pdev)
+{
+	struct timbgpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
+	struct timbgpio *tgpio = platform_get_drvdata(pdev);
+	int irq = platform_get_irq(pdev, 0);
+
+	if (irq >= 0 && tgpio->irq_base > 0) {
+		int i;
+		for (i = 0; i < pdata->nr_pins; i++) {
+			irq_set_chip(tgpio->irq_base + i, NULL);
+			irq_set_chip_data(tgpio->irq_base + i, NULL);
+		}
+
+		irq_set_handler(irq, NULL);
+		irq_set_handler_data(irq, NULL);
+	}
+
+	gpiochip_remove(&tgpio->gpio);
+
+	return 0;
+}
+
+static struct platform_driver timbgpio_platform_driver = {
+	.driver = {
+		.name	= DRIVER_NAME,
+	},
+	.probe		= timbgpio_probe,
+	.remove		= timbgpio_remove,
+};
+
+/*--------------------------------------------------------------------------*/
+
+module_platform_driver(timbgpio_platform_driver);
+
+MODULE_DESCRIPTION("Timberdale GPIO driver");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Mocean Laboratories");
+MODULE_ALIAS("platform:"DRIVER_NAME);
+