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path: root/drivers/gpio/gpio-mxc.c
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-rw-r--r--drivers/gpio/gpio-mxc.c566
1 files changed, 566 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-mxc.c b/drivers/gpio/gpio-mxc.c
new file mode 100644
index 000000000..853d9aa6b
--- /dev/null
+++ b/drivers/gpio/gpio-mxc.c
@@ -0,0 +1,566 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
+// Copyright 2008 Juergen Beisert, kernel@pengutronix.de
+//
+// Based on code from Freescale Semiconductor,
+// Authors: Daniel Mack, Juergen Beisert.
+// Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
+
+#include <linux/clk.h>
+#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/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/syscore_ops.h>
+#include <linux/gpio/driver.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/bug.h>
+
+/* 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_reg_saved {
+ u32 icr1;
+ u32 icr2;
+ u32 imr;
+ u32 gdir;
+ u32 edge_sel;
+ u32 dr;
+};
+
+struct mxc_gpio_port {
+ struct list_head node;
+ void __iomem *base;
+ struct clk *clk;
+ int irq;
+ int irq_high;
+ struct irq_domain *domain;
+ struct gpio_chip gc;
+ struct device *dev;
+ u32 both_edges;
+ struct mxc_gpio_reg_saved gpio_saved_reg;
+ bool power_off;
+ const struct mxc_gpio_hwdata *hwdata;
+};
+
+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,
+};
+
+#define GPIO_DR (port->hwdata->dr_reg)
+#define GPIO_GDIR (port->hwdata->gdir_reg)
+#define GPIO_PSR (port->hwdata->psr_reg)
+#define GPIO_ICR1 (port->hwdata->icr1_reg)
+#define GPIO_ICR2 (port->hwdata->icr2_reg)
+#define GPIO_IMR (port->hwdata->imr_reg)
+#define GPIO_ISR (port->hwdata->isr_reg)
+#define GPIO_EDGE_SEL (port->hwdata->edge_sel_reg)
+
+#define GPIO_INT_LOW_LEV (port->hwdata->low_level)
+#define GPIO_INT_HIGH_LEV (port->hwdata->high_level)
+#define GPIO_INT_RISE_EDGE (port->hwdata->rise_edge)
+#define GPIO_INT_FALL_EDGE (port->hwdata->fall_edge)
+#define GPIO_INT_BOTH_EDGES 0x4
+
+static const struct of_device_id mxc_gpio_dt_ids[] = {
+ { .compatible = "fsl,imx1-gpio", .data = &imx1_imx21_gpio_hwdata },
+ { .compatible = "fsl,imx21-gpio", .data = &imx1_imx21_gpio_hwdata },
+ { .compatible = "fsl,imx31-gpio", .data = &imx31_gpio_hwdata },
+ { .compatible = "fsl,imx35-gpio", .data = &imx35_gpio_hwdata },
+ { .compatible = "fsl,imx7d-gpio", .data = &imx35_gpio_hwdata },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mxc_gpio_dt_ids);
+
+/*
+ * 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;
+ unsigned long flags;
+ u32 bit, val;
+ u32 gpio_idx = d->hwirq;
+ 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 = port->gc.get(&port->gc, gpio_idx);
+ if (val) {
+ edge = GPIO_INT_LOW_LEV;
+ pr_debug("mxc: set GPIO %d to low trigger\n", gpio_idx);
+ } else {
+ edge = GPIO_INT_HIGH_LEV;
+ pr_debug("mxc: set GPIO %d to high trigger\n", gpio_idx);
+ }
+ 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;
+ }
+
+ raw_spin_lock_irqsave(&port->gc.bgpio_lock, flags);
+
+ 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);
+
+ raw_spin_unlock_irqrestore(&port->gc.bgpio_lock, flags);
+
+ return port->gc.direction_input(&port->gc, gpio_idx);
+}
+
+static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio)
+{
+ void __iomem *reg = port->base;
+ unsigned long flags;
+ u32 bit, val;
+ int edge;
+
+ raw_spin_lock_irqsave(&port->gc.bgpio_lock, flags);
+
+ 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);
+ goto unlock;
+ }
+ writel(val | (edge << (bit << 1)), reg);
+
+unlock:
+ raw_spin_unlock_irqrestore(&port->gc.bgpio_lock, flags);
+}
+
+/* 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_domain_irq(port->domain, irqoffset);
+
+ irq_stat &= ~(1 << irqoffset);
+ }
+}
+
+/* MX1 and MX3 has one interrupt *per* gpio port */
+static void mx3_gpio_irq_handler(struct irq_desc *desc)
+{
+ u32 irq_stat;
+ struct mxc_gpio_port *port = irq_desc_get_handler_data(desc);
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+
+ 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(struct irq_desc *desc)
+{
+ u32 irq_msk, irq_stat;
+ struct mxc_gpio_port *port;
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+
+ 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;
+ int ret;
+
+ if (enable) {
+ if (port->irq_high && (gpio_idx >= 16))
+ ret = enable_irq_wake(port->irq_high);
+ else
+ ret = enable_irq_wake(port->irq);
+ } else {
+ if (port->irq_high && (gpio_idx >= 16))
+ ret = disable_irq_wake(port->irq_high);
+ else
+ ret = disable_irq_wake(port->irq);
+ }
+
+ return ret;
+}
+
+static int mxc_gpio_init_gc(struct mxc_gpio_port *port, int irq_base)
+{
+ struct irq_chip_generic *gc;
+ struct irq_chip_type *ct;
+ int rv;
+
+ gc = devm_irq_alloc_generic_chip(port->dev, "gpio-mxc", 1, irq_base,
+ port->base, handle_level_irq);
+ if (!gc)
+ return -ENOMEM;
+ 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->chip.flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND;
+ ct->regs.ack = GPIO_ISR;
+ ct->regs.mask = GPIO_IMR;
+
+ rv = devm_irq_setup_generic_chip(port->dev, gc, IRQ_MSK(32),
+ IRQ_GC_INIT_NESTED_LOCK,
+ IRQ_NOREQUEST, 0);
+
+ return rv;
+}
+
+static int mxc_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
+{
+ struct mxc_gpio_port *port = gpiochip_get_data(gc);
+
+ 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;
+ int irq_count;
+ int irq_base;
+ int err;
+
+ port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
+ if (!port)
+ return -ENOMEM;
+
+ port->dev = &pdev->dev;
+
+ port->hwdata = device_get_match_data(&pdev->dev);
+
+ port->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(port->base))
+ return PTR_ERR(port->base);
+
+ irq_count = platform_irq_count(pdev);
+ if (irq_count < 0)
+ return irq_count;
+
+ if (irq_count > 1) {
+ port->irq_high = platform_get_irq(pdev, 1);
+ if (port->irq_high < 0)
+ port->irq_high = 0;
+ }
+
+ port->irq = platform_get_irq(pdev, 0);
+ if (port->irq < 0)
+ return port->irq;
+
+ /* the controller clock is optional */
+ port->clk = devm_clk_get_optional(&pdev->dev, NULL);
+ if (IS_ERR(port->clk))
+ return PTR_ERR(port->clk);
+
+ err = clk_prepare_enable(port->clk);
+ if (err) {
+ dev_err(&pdev->dev, "Unable to enable clock.\n");
+ return err;
+ }
+
+ if (of_device_is_compatible(np, "fsl,imx7d-gpio"))
+ port->power_off = true;
+
+ /* disable the interrupt and clear the status */
+ writel(0, port->base + GPIO_IMR);
+ writel(~0, port->base + GPIO_ISR);
+
+ if (of_device_is_compatible(np, "fsl,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_and_data(port->irq,
+ mx3_gpio_irq_handler, port);
+ if (port->irq_high > 0)
+ /* setup handler for GPIO 16 to 31 */
+ irq_set_chained_handler_and_data(port->irq_high,
+ mx3_gpio_irq_handler,
+ port);
+ }
+
+ err = bgpio_init(&port->gc, &pdev->dev, 4,
+ port->base + GPIO_PSR,
+ port->base + GPIO_DR, NULL,
+ port->base + GPIO_GDIR, NULL,
+ BGPIOF_READ_OUTPUT_REG_SET);
+ if (err)
+ goto out_bgio;
+
+ port->gc.request = gpiochip_generic_request;
+ port->gc.free = gpiochip_generic_free;
+ port->gc.to_irq = mxc_gpio_to_irq;
+ port->gc.base = (pdev->id < 0) ? of_alias_get_id(np, "gpio") * 32 :
+ pdev->id * 32;
+
+ err = devm_gpiochip_add_data(&pdev->dev, &port->gc, port);
+ if (err)
+ goto out_bgio;
+
+ irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0, 32, numa_node_id());
+ if (irq_base < 0) {
+ err = irq_base;
+ goto out_bgio;
+ }
+
+ port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
+ &irq_domain_simple_ops, NULL);
+ if (!port->domain) {
+ err = -ENODEV;
+ goto out_bgio;
+ }
+
+ /* gpio-mxc can be a generic irq chip */
+ err = mxc_gpio_init_gc(port, irq_base);
+ if (err < 0)
+ goto out_irqdomain_remove;
+
+ list_add_tail(&port->node, &mxc_gpio_ports);
+
+ platform_set_drvdata(pdev, port);
+
+ return 0;
+
+out_irqdomain_remove:
+ irq_domain_remove(port->domain);
+out_bgio:
+ clk_disable_unprepare(port->clk);
+ dev_info(&pdev->dev, "%s failed with errno %d\n", __func__, err);
+ return err;
+}
+
+static void mxc_gpio_save_regs(struct mxc_gpio_port *port)
+{
+ if (!port->power_off)
+ return;
+
+ port->gpio_saved_reg.icr1 = readl(port->base + GPIO_ICR1);
+ port->gpio_saved_reg.icr2 = readl(port->base + GPIO_ICR2);
+ port->gpio_saved_reg.imr = readl(port->base + GPIO_IMR);
+ port->gpio_saved_reg.gdir = readl(port->base + GPIO_GDIR);
+ port->gpio_saved_reg.edge_sel = readl(port->base + GPIO_EDGE_SEL);
+ port->gpio_saved_reg.dr = readl(port->base + GPIO_DR);
+}
+
+static void mxc_gpio_restore_regs(struct mxc_gpio_port *port)
+{
+ if (!port->power_off)
+ return;
+
+ writel(port->gpio_saved_reg.icr1, port->base + GPIO_ICR1);
+ writel(port->gpio_saved_reg.icr2, port->base + GPIO_ICR2);
+ writel(port->gpio_saved_reg.imr, port->base + GPIO_IMR);
+ writel(port->gpio_saved_reg.gdir, port->base + GPIO_GDIR);
+ writel(port->gpio_saved_reg.edge_sel, port->base + GPIO_EDGE_SEL);
+ writel(port->gpio_saved_reg.dr, port->base + GPIO_DR);
+}
+
+static int mxc_gpio_syscore_suspend(void)
+{
+ struct mxc_gpio_port *port;
+
+ /* walk through all ports */
+ list_for_each_entry(port, &mxc_gpio_ports, node) {
+ mxc_gpio_save_regs(port);
+ clk_disable_unprepare(port->clk);
+ }
+
+ return 0;
+}
+
+static void mxc_gpio_syscore_resume(void)
+{
+ struct mxc_gpio_port *port;
+ int ret;
+
+ /* walk through all ports */
+ list_for_each_entry(port, &mxc_gpio_ports, node) {
+ ret = clk_prepare_enable(port->clk);
+ if (ret) {
+ pr_err("mxc: failed to enable gpio clock %d\n", ret);
+ return;
+ }
+ mxc_gpio_restore_regs(port);
+ }
+}
+
+static struct syscore_ops mxc_gpio_syscore_ops = {
+ .suspend = mxc_gpio_syscore_suspend,
+ .resume = mxc_gpio_syscore_resume,
+};
+
+static struct platform_driver mxc_gpio_driver = {
+ .driver = {
+ .name = "gpio-mxc",
+ .of_match_table = mxc_gpio_dt_ids,
+ .suppress_bind_attrs = true,
+ },
+ .probe = mxc_gpio_probe,
+};
+
+static int __init gpio_mxc_init(void)
+{
+ register_syscore_ops(&mxc_gpio_syscore_ops);
+
+ return platform_driver_register(&mxc_gpio_driver);
+}
+subsys_initcall(gpio_mxc_init);
+
+MODULE_AUTHOR("Shawn Guo <shawn.guo@linaro.org>");
+MODULE_DESCRIPTION("i.MX GPIO Driver");
+MODULE_LICENSE("GPL");