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path: root/kernel/drivers/gpio/gpio-mxc.c
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Diffstat (limited to 'kernel/drivers/gpio/gpio-mxc.c')
-rw-r--r--kernel/drivers/gpio/gpio-mxc.c515
1 files changed, 515 insertions, 0 deletions
diff --git a/kernel/drivers/gpio/gpio-mxc.c b/kernel/drivers/gpio/gpio-mxc.c
new file mode 100644
index 000000000..9f7446a7a
--- /dev/null
+++ b/kernel/drivers/gpio/gpio-mxc.c
@@ -0,0 +1,515 @@
+/*
+ * 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/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip/chained_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 <linux/module.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 i.mx31 */
+ IMX35_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;
+ int edge_sel_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;
+ struct irq_domain *domain;
+ 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,
+ .edge_sel_reg = -EINVAL,
+ .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,
+ .edge_sel_reg = -EINVAL,
+ .low_level = 0x00,
+ .high_level = 0x01,
+ .rise_edge = 0x02,
+ .fall_edge = 0x03,
+};
+
+static struct mxc_gpio_hwdata imx35_gpio_hwdata = {
+ .dr_reg = 0x00,
+ .gdir_reg = 0x04,
+ .psr_reg = 0x08,
+ .icr1_reg = 0x0c,
+ .icr2_reg = 0x10,
+ .imr_reg = 0x14,
+ .isr_reg = 0x18,
+ .edge_sel_reg = 0x1c,
+ .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_EDGE_SEL (mxc_gpio_hwdata->edge_sel_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_BOTH_EDGES 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,
+ }, {
+ .name = "imx35-gpio",
+ .driver_data = IMX35_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], },
+ { .compatible = "fsl,imx35-gpio", .data = &mxc_gpio_devtype[IMX35_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)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ struct mxc_gpio_port *port = gc->private;
+ u32 bit, val;
+ u32 gpio_idx = d->hwirq;
+ u32 gpio = port->bgc.gc.base + gpio_idx;
+ int edge;
+ void __iomem *reg = port->base;
+
+ port->both_edges &= ~(1 << gpio_idx);
+ 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:
+ if (GPIO_EDGE_SEL >= 0) {
+ edge = GPIO_INT_BOTH_EDGES;
+ } else {
+ 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_idx;
+ }
+ 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;
+ }
+
+ if (GPIO_EDGE_SEL >= 0) {
+ val = readl(port->base + GPIO_EDGE_SEL);
+ if (edge == GPIO_INT_BOTH_EDGES)
+ writel(val | (1 << gpio_idx),
+ port->base + GPIO_EDGE_SEL);
+ else
+ writel(val & ~(1 << gpio_idx),
+ port->base + GPIO_EDGE_SEL);
+ }
+
+ if (edge != GPIO_INT_BOTH_EDGES) {
+ reg += GPIO_ICR1 + ((gpio_idx & 0x10) >> 2); /* lower or upper register */
+ bit = gpio_idx & 0xf;
+ val = readl(reg) & ~(0x3 << (bit << 1));
+ writel(val | (edge << (bit << 1)), reg);
+ }
+
+ writel(1 << gpio_idx, 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)
+{
+ while (irq_stat != 0) {
+ int irqoffset = fls(irq_stat) - 1;
+
+ if (port->both_edges & (1 << irqoffset))
+ mxc_flip_edge(port, irqoffset);
+
+ generic_handle_irq(irq_find_mapping(port->domain, 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);
+ struct irq_chip *chip = irq_get_chip(irq);
+
+ chained_irq_enter(chip, desc);
+
+ irq_stat = readl(port->base + GPIO_ISR) & readl(port->base + GPIO_IMR);
+
+ mxc_gpio_irq_handler(port, irq_stat);
+
+ chained_irq_exit(chip, desc);
+}
+
+/* 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;
+ struct irq_chip *chip = irq_get_chip(irq);
+
+ chained_irq_enter(chip, desc);
+
+ /* 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);
+ }
+ chained_irq_exit(chip, desc);
+}
+
+/*
+ * 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)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ struct mxc_gpio_port *port = gc->private;
+ u32 gpio_idx = d->hwirq;
+
+ 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, int irq_base)
+{
+ struct irq_chip_generic *gc;
+ struct irq_chip_type *ct;
+
+ gc = irq_alloc_generic_chip("gpio-mxc", 1, irq_base,
+ 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 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 == IMX35_GPIO)
+ mxc_gpio_hwdata = &imx35_gpio_hwdata;
+ else if (hwtype == IMX31_GPIO)
+ mxc_gpio_hwdata = &imx31_gpio_hwdata;
+ else
+ mxc_gpio_hwdata = &imx1_imx21_gpio_hwdata;
+
+ mxc_gpio_hwtype = hwtype;
+}
+
+static int mxc_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
+{
+ struct bgpio_chip *bgc = to_bgpio_chip(gc);
+ struct mxc_gpio_port *port =
+ container_of(bgc, struct mxc_gpio_port, bgc);
+
+ return irq_find_mapping(port->domain, offset);
+}
+
+static int mxc_gpio_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct mxc_gpio_port *port;
+ struct resource *iores;
+ int irq_base;
+ int err;
+
+ mxc_gpio_get_hw(pdev);
+
+ port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
+ if (!port)
+ return -ENOMEM;
+
+ iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ port->base = devm_ioremap_resource(&pdev->dev, iores);
+ if (IS_ERR(port->base))
+ return PTR_ERR(port->base);
+
+ port->irq_high = platform_get_irq(pdev, 1);
+ port->irq = platform_get_irq(pdev, 0);
+ if (port->irq < 0)
+ return port->irq;
+
+ /* 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. Actually setting
+ * the handler is needed only once, but doing it for every port
+ * is more robust and easier.
+ */
+ 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, 0);
+ if (err)
+ goto out_bgio;
+
+ port->bgc.gc.to_irq = mxc_gpio_to_irq;
+ port->bgc.gc.base = (pdev->id < 0) ? of_alias_get_id(np, "gpio") * 32 :
+ pdev->id * 32;
+
+ err = gpiochip_add(&port->bgc.gc);
+ if (err)
+ goto out_bgpio_remove;
+
+ irq_base = irq_alloc_descs(-1, 0, 32, numa_node_id());
+ if (irq_base < 0) {
+ err = irq_base;
+ goto out_gpiochip_remove;
+ }
+
+ port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
+ &irq_domain_simple_ops, NULL);
+ if (!port->domain) {
+ err = -ENODEV;
+ goto out_irqdesc_free;
+ }
+
+ /* gpio-mxc can be a generic irq chip */
+ mxc_gpio_init_gc(port, irq_base);
+
+ list_add_tail(&port->node, &mxc_gpio_ports);
+
+ return 0;
+
+out_irqdesc_free:
+ irq_free_descs(irq_base, 32);
+out_gpiochip_remove:
+ gpiochip_remove(&port->bgc.gc);
+out_bgpio_remove:
+ bgpio_remove(&port->bgc);
+out_bgio:
+ 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",
+ .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");