1 files changed, 460 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-mxc.c b/drivers/gpio/gpio-mxc.c
new file mode 100644
index 000000000000..4340acae3bd3
--- /dev/null
+++ b/drivers/gpio/gpio-mxc.c
@@ -0,0 +1,460 @@
+/*
+ * MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
+ * Copyright 2008 Juergen Beisert, kernel@pengutronix.de
+ *
+ * Based on code from Freescale,
+ * Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/gpio.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/basic_mmio_gpio.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <asm-generic/bug.h>
+
+enum mxc_gpio_hwtype {
+	IMX1_GPIO,	/* runs on i.mx1 */
+	IMX21_GPIO,	/* runs on i.mx21 and i.mx27 */
+	IMX31_GPIO,	/* runs on all other i.mx */
+};
+
+/* device type dependent stuff */
+struct mxc_gpio_hwdata {
+	unsigned dr_reg;
+	unsigned gdir_reg;
+	unsigned psr_reg;
+	unsigned icr1_reg;
+	unsigned icr2_reg;
+	unsigned imr_reg;
+	unsigned isr_reg;
+	unsigned low_level;
+	unsigned high_level;
+	unsigned rise_edge;
+	unsigned fall_edge;
+};
+
+struct mxc_gpio_port {
+	struct list_head node;
+	void __iomem *base;
+	int irq;
+	int irq_high;
+	int virtual_irq_start;
+	struct bgpio_chip bgc;
+	u32 both_edges;
+};
+
+static struct mxc_gpio_hwdata imx1_imx21_gpio_hwdata = {
+	.dr_reg		= 0x1c,
+	.gdir_reg	= 0x00,
+	.psr_reg	= 0x24,
+	.icr1_reg	= 0x28,
+	.icr2_reg	= 0x2c,
+	.imr_reg	= 0x30,
+	.isr_reg	= 0x34,
+	.low_level	= 0x03,
+	.high_level	= 0x02,
+	.rise_edge	= 0x00,
+	.fall_edge	= 0x01,
+};
+
+static struct mxc_gpio_hwdata imx31_gpio_hwdata = {
+	.dr_reg		= 0x00,
+	.gdir_reg	= 0x04,
+	.psr_reg	= 0x08,
+	.icr1_reg	= 0x0c,
+	.icr2_reg	= 0x10,
+	.imr_reg	= 0x14,
+	.isr_reg	= 0x18,
+	.low_level	= 0x00,
+	.high_level	= 0x01,
+	.rise_edge	= 0x02,
+	.fall_edge	= 0x03,
+};
+
+static enum mxc_gpio_hwtype mxc_gpio_hwtype;
+static struct mxc_gpio_hwdata *mxc_gpio_hwdata;
+
+#define GPIO_DR			(mxc_gpio_hwdata->dr_reg)
+#define GPIO_GDIR		(mxc_gpio_hwdata->gdir_reg)
+#define GPIO_PSR		(mxc_gpio_hwdata->psr_reg)
+#define GPIO_ICR1		(mxc_gpio_hwdata->icr1_reg)
+#define GPIO_ICR2		(mxc_gpio_hwdata->icr2_reg)
+#define GPIO_IMR		(mxc_gpio_hwdata->imr_reg)
+#define GPIO_ISR		(mxc_gpio_hwdata->isr_reg)
+
+#define GPIO_INT_LOW_LEV	(mxc_gpio_hwdata->low_level)
+#define GPIO_INT_HIGH_LEV	(mxc_gpio_hwdata->high_level)
+#define GPIO_INT_RISE_EDGE	(mxc_gpio_hwdata->rise_edge)
+#define GPIO_INT_FALL_EDGE	(mxc_gpio_hwdata->fall_edge)
+#define GPIO_INT_NONE		0x4
+
+static struct platform_device_id mxc_gpio_devtype[] = {
+	{
+		.name = "imx1-gpio",
+		.driver_data = IMX1_GPIO,
+	}, {
+		.name = "imx21-gpio",
+		.driver_data = IMX21_GPIO,
+	}, {
+		.name = "imx31-gpio",
+		.driver_data = IMX31_GPIO,
+	}, {
+		/* sentinel */
+	}
+};
+
+static const struct of_device_id mxc_gpio_dt_ids[] = {
+	{ .compatible = "fsl,imx1-gpio", .data = &mxc_gpio_devtype[IMX1_GPIO], },
+	{ .compatible = "fsl,imx21-gpio", .data = &mxc_gpio_devtype[IMX21_GPIO], },
+	{ .compatible = "fsl,imx31-gpio", .data = &mxc_gpio_devtype[IMX31_GPIO], },
+	{ /* sentinel */ }
+};
+
+/*
+ * MX2 has one interrupt *for all* gpio ports. The list is used
+ * to save the references to all ports, so that mx2_gpio_irq_handler
+ * can walk through all interrupt status registers.
+ */
+static LIST_HEAD(mxc_gpio_ports);
+
+/* Note: This driver assumes 32 GPIOs are handled in one register */
+
+static int gpio_set_irq_type(struct irq_data *d, u32 type)
+{
+	u32 gpio = irq_to_gpio(d->irq);
+	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+	struct mxc_gpio_port *port = gc->private;
+	u32 bit, val;
+	int edge;
+	void __iomem *reg = port->base;
+
+	port->both_edges &= ~(1 << (gpio & 31));
+	switch (type) {
+	case IRQ_TYPE_EDGE_RISING:
+		edge = GPIO_INT_RISE_EDGE;
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		edge = GPIO_INT_FALL_EDGE;
+		break;
+	case IRQ_TYPE_EDGE_BOTH:
+		val = gpio_get_value(gpio);
+		if (val) {
+			edge = GPIO_INT_LOW_LEV;
+			pr_debug("mxc: set GPIO %d to low trigger\n", gpio);
+		} else {
+			edge = GPIO_INT_HIGH_LEV;
+			pr_debug("mxc: set GPIO %d to high trigger\n", gpio);
+		}
+		port->both_edges |= 1 << (gpio & 31);
+		break;
+	case IRQ_TYPE_LEVEL_LOW:
+		edge = GPIO_INT_LOW_LEV;
+		break;
+	case IRQ_TYPE_LEVEL_HIGH:
+		edge = GPIO_INT_HIGH_LEV;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */
+	bit = gpio & 0xf;
+	val = readl(reg) & ~(0x3 << (bit << 1));
+	writel(val | (edge << (bit << 1)), reg);
+	writel(1 << (gpio & 0x1f), port->base + GPIO_ISR);
+
+	return 0;
+}
+
+static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio)
+{
+	void __iomem *reg = port->base;
+	u32 bit, val;
+	int edge;
+
+	reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */
+	bit = gpio & 0xf;
+	val = readl(reg);
+	edge = (val >> (bit << 1)) & 3;
+	val &= ~(0x3 << (bit << 1));
+	if (edge == GPIO_INT_HIGH_LEV) {
+		edge = GPIO_INT_LOW_LEV;
+		pr_debug("mxc: switch GPIO %d to low trigger\n", gpio);
+	} else if (edge == GPIO_INT_LOW_LEV) {
+		edge = GPIO_INT_HIGH_LEV;
+		pr_debug("mxc: switch GPIO %d to high trigger\n", gpio);
+	} else {
+		pr_err("mxc: invalid configuration for GPIO %d: %x\n",
+		       gpio, edge);
+		return;
+	}
+	writel(val | (edge << (bit << 1)), reg);
+}
+
+/* handle 32 interrupts in one status register */
+static void mxc_gpio_irq_handler(struct mxc_gpio_port *port, u32 irq_stat)
+{
+	u32 gpio_irq_no_base = port->virtual_irq_start;
+
+	while (irq_stat != 0) {
+		int irqoffset = fls(irq_stat) - 1;
+
+		if (port->both_edges & (1 << irqoffset))
+			mxc_flip_edge(port, irqoffset);
+
+		generic_handle_irq(gpio_irq_no_base + irqoffset);
+
+		irq_stat &= ~(1 << irqoffset);
+	}
+}
+
+/* MX1 and MX3 has one interrupt *per* gpio port */
+static void mx3_gpio_irq_handler(u32 irq, struct irq_desc *desc)
+{
+	u32 irq_stat;
+	struct mxc_gpio_port *port = irq_get_handler_data(irq);
+
+	irq_stat = readl(port->base + GPIO_ISR) & readl(port->base + GPIO_IMR);
+
+	mxc_gpio_irq_handler(port, irq_stat);
+}
+
+/* MX2 has one interrupt *for all* gpio ports */
+static void mx2_gpio_irq_handler(u32 irq, struct irq_desc *desc)
+{
+	u32 irq_msk, irq_stat;
+	struct mxc_gpio_port *port;
+
+	/* walk through all interrupt status registers */
+	list_for_each_entry(port, &mxc_gpio_ports, node) {
+		irq_msk = readl(port->base + GPIO_IMR);
+		if (!irq_msk)
+			continue;
+
+		irq_stat = readl(port->base + GPIO_ISR) & irq_msk;
+		if (irq_stat)
+			mxc_gpio_irq_handler(port, irq_stat);
+	}
+}
+
+/*
+ * Set interrupt number "irq" in the GPIO as a wake-up source.
+ * While system is running, all registered GPIO interrupts need to have
+ * wake-up enabled. When system is suspended, only selected GPIO interrupts
+ * need to have wake-up enabled.
+ * @param  irq          interrupt source number
+ * @param  enable       enable as wake-up if equal to non-zero
+ * @return       This function returns 0 on success.
+ */
+static int gpio_set_wake_irq(struct irq_data *d, u32 enable)
+{
+	u32 gpio = irq_to_gpio(d->irq);
+	u32 gpio_idx = gpio & 0x1F;
+	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+	struct mxc_gpio_port *port = gc->private;
+
+	if (enable) {
+		if (port->irq_high && (gpio_idx >= 16))
+			enable_irq_wake(port->irq_high);
+		else
+			enable_irq_wake(port->irq);
+	} else {
+		if (port->irq_high && (gpio_idx >= 16))
+			disable_irq_wake(port->irq_high);
+		else
+			disable_irq_wake(port->irq);
+	}
+
+	return 0;
+}
+
+static void __init mxc_gpio_init_gc(struct mxc_gpio_port *port)
+{
+	struct irq_chip_generic *gc;
+	struct irq_chip_type *ct;
+
+	gc = irq_alloc_generic_chip("gpio-mxc", 1, port->virtual_irq_start,
+				    port->base, handle_level_irq);
+	gc->private = port;
+
+	ct = gc->chip_types;
+	ct->chip.irq_ack = irq_gc_ack_set_bit;
+	ct->chip.irq_mask = irq_gc_mask_clr_bit;
+	ct->chip.irq_unmask = irq_gc_mask_set_bit;
+	ct->chip.irq_set_type = gpio_set_irq_type;
+	ct->chip.irq_set_wake = gpio_set_wake_irq;
+	ct->regs.ack = GPIO_ISR;
+	ct->regs.mask = GPIO_IMR;
+
+	irq_setup_generic_chip(gc, IRQ_MSK(32), IRQ_GC_INIT_NESTED_LOCK,
+			       IRQ_NOREQUEST, 0);
+}
+
+static void __devinit mxc_gpio_get_hw(struct platform_device *pdev)
+{
+	const struct of_device_id *of_id =
+			of_match_device(mxc_gpio_dt_ids, &pdev->dev);
+	enum mxc_gpio_hwtype hwtype;
+
+	if (of_id)
+		pdev->id_entry = of_id->data;
+	hwtype = pdev->id_entry->driver_data;
+
+	if (mxc_gpio_hwtype) {
+		/*
+		 * The driver works with a reasonable presupposition,
+		 * that is all gpio ports must be the same type when
+		 * running on one soc.
+		 */
+		BUG_ON(mxc_gpio_hwtype != hwtype);
+		return;
+	}
+
+	if (hwtype == IMX31_GPIO)
+		mxc_gpio_hwdata = &imx31_gpio_hwdata;
+	else
+		mxc_gpio_hwdata = &imx1_imx21_gpio_hwdata;
+
+	mxc_gpio_hwtype = hwtype;
+}
+
+static int __devinit mxc_gpio_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct mxc_gpio_port *port;
+	struct resource *iores;
+	int err;
+
+	mxc_gpio_get_hw(pdev);
+
+	port = kzalloc(sizeof(struct mxc_gpio_port), GFP_KERNEL);
+	if (!port)
+		return -ENOMEM;
+
+	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!iores) {
+		err = -ENODEV;
+		goto out_kfree;
+	}
+
+	if (!request_mem_region(iores->start, resource_size(iores),
+				pdev->name)) {
+		err = -EBUSY;
+		goto out_kfree;
+	}
+
+	port->base = ioremap(iores->start, resource_size(iores));
+	if (!port->base) {
+		err = -ENOMEM;
+		goto out_release_mem;
+	}
+
+	port->irq_high = platform_get_irq(pdev, 1);
+	port->irq = platform_get_irq(pdev, 0);
+	if (port->irq < 0) {
+		err = -EINVAL;
+		goto out_iounmap;
+	}
+
+	/* disable the interrupt and clear the status */
+	writel(0, port->base + GPIO_IMR);
+	writel(~0, port->base + GPIO_ISR);
+
+	if (mxc_gpio_hwtype == IMX21_GPIO) {
+		/* setup one handler for all GPIO interrupts */
+		if (pdev->id == 0)
+			irq_set_chained_handler(port->irq,
+						mx2_gpio_irq_handler);
+	} else {
+		/* setup one handler for each entry */
+		irq_set_chained_handler(port->irq, mx3_gpio_irq_handler);
+		irq_set_handler_data(port->irq, port);
+		if (port->irq_high > 0) {
+			/* setup handler for GPIO 16 to 31 */
+			irq_set_chained_handler(port->irq_high,
+						mx3_gpio_irq_handler);
+			irq_set_handler_data(port->irq_high, port);
+		}
+	}
+
+	err = bgpio_init(&port->bgc, &pdev->dev, 4,
+			 port->base + GPIO_PSR,
+			 port->base + GPIO_DR, NULL,
+			 port->base + GPIO_GDIR, NULL, false);
+	if (err)
+		goto out_iounmap;
+
+	port->bgc.gc.base = pdev->id * 32;
+	port->bgc.dir = port->bgc.read_reg(port->bgc.reg_dir);
+	port->bgc.data = port->bgc.read_reg(port->bgc.reg_set);
+
+	err = gpiochip_add(&port->bgc.gc);
+	if (err)
+		goto out_bgpio_remove;
+
+	/*
+	 * In dt case, we use gpio number range dynamically
+	 * allocated by gpio core.
+	 */
+	port->virtual_irq_start = MXC_GPIO_IRQ_START + (np ? port->bgc.gc.base :
+							     pdev->id * 32);
+
+	/* gpio-mxc can be a generic irq chip */
+	mxc_gpio_init_gc(port);
+
+	list_add_tail(&port->node, &mxc_gpio_ports);
+
+	return 0;
+
+out_bgpio_remove:
+	bgpio_remove(&port->bgc);
+out_iounmap:
+	iounmap(port->base);
+out_release_mem:
+	release_mem_region(iores->start, resource_size(iores));
+out_kfree:
+	kfree(port);
+	dev_info(&pdev->dev, "%s failed with errno %d\n", __func__, err);
+	return err;
+}
+
+static struct platform_driver mxc_gpio_driver = {
+	.driver		= {
+		.name	= "gpio-mxc",
+		.owner	= THIS_MODULE,
+		.of_match_table = mxc_gpio_dt_ids,
+	},
+	.probe		= mxc_gpio_probe,
+	.id_table	= mxc_gpio_devtype,
+};
+
+static int __init gpio_mxc_init(void)
+{
+	return platform_driver_register(&mxc_gpio_driver);
+}
+postcore_initcall(gpio_mxc_init);
+
+MODULE_AUTHOR("Freescale Semiconductor, "
+	      "Daniel Mack <danielncaiaq.de>, "
+	      "Juergen Beisert <kernel@pengutronix.de>");
+MODULE_DESCRIPTION("Freescale MXC GPIO");
+MODULE_LICENSE("GPL");