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path: root/drivers/gpio/gpio-pl061.c
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-rw-r--r--drivers/gpio/gpio-pl061.c441
1 files changed, 441 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-pl061.c b/drivers/gpio/gpio-pl061.c
new file mode 100644
index 0000000000..9fc1f3dd41
--- /dev/null
+++ b/drivers/gpio/gpio-pl061.c
@@ -0,0 +1,441 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2008, 2009 Provigent Ltd.
+ *
+ * Author: Baruch Siach <baruch@tkos.co.il>
+ *
+ * Driver for the ARM PrimeCell(tm) General Purpose Input/Output (PL061)
+ *
+ * Data sheet: ARM DDI 0190B, September 2000
+ */
+#include <linux/amba/bus.h>
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/gpio/driver.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/module.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/pm.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/spinlock.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 {
+ raw_spinlock_t lock;
+
+ void __iomem *base;
+ struct gpio_chip gc;
+ int parent_irq;
+
+#ifdef CONFIG_PM
+ struct pl061_context_save_regs csave_regs;
+#endif
+};
+
+static int pl061_get_direction(struct gpio_chip *gc, unsigned offset)
+{
+ struct pl061 *pl061 = gpiochip_get_data(gc);
+
+ if (readb(pl061->base + GPIODIR) & BIT(offset))
+ return GPIO_LINE_DIRECTION_OUT;
+
+ return GPIO_LINE_DIRECTION_IN;
+}
+
+static int pl061_direction_input(struct gpio_chip *gc, unsigned offset)
+{
+ struct pl061 *pl061 = gpiochip_get_data(gc);
+ unsigned long flags;
+ unsigned char gpiodir;
+
+ raw_spin_lock_irqsave(&pl061->lock, flags);
+ gpiodir = readb(pl061->base + GPIODIR);
+ gpiodir &= ~(BIT(offset));
+ writeb(gpiodir, pl061->base + GPIODIR);
+ raw_spin_unlock_irqrestore(&pl061->lock, flags);
+
+ return 0;
+}
+
+static int pl061_direction_output(struct gpio_chip *gc, unsigned offset,
+ int value)
+{
+ struct pl061 *pl061 = gpiochip_get_data(gc);
+ unsigned long flags;
+ unsigned char gpiodir;
+
+ raw_spin_lock_irqsave(&pl061->lock, flags);
+ writeb(!!value << offset, pl061->base + (BIT(offset + 2)));
+ gpiodir = readb(pl061->base + GPIODIR);
+ gpiodir |= BIT(offset);
+ writeb(gpiodir, pl061->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, pl061->base + (BIT(offset + 2)));
+ raw_spin_unlock_irqrestore(&pl061->lock, flags);
+
+ return 0;
+}
+
+static int pl061_get_value(struct gpio_chip *gc, unsigned offset)
+{
+ struct pl061 *pl061 = gpiochip_get_data(gc);
+
+ return !!readb(pl061->base + (BIT(offset + 2)));
+}
+
+static void pl061_set_value(struct gpio_chip *gc, unsigned offset, int value)
+{
+ struct pl061 *pl061 = gpiochip_get_data(gc);
+
+ writeb(!!value << offset, pl061->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 *pl061 = gpiochip_get_data(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;
+
+ if ((trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) &&
+ (trigger & (IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING)))
+ {
+ dev_err(gc->parent,
+ "trying to configure line %d for both level and edge "
+ "detection, choose one!\n",
+ offset);
+ return -EINVAL;
+ }
+
+
+ raw_spin_lock_irqsave(&pl061->lock, flags);
+
+ gpioiev = readb(pl061->base + GPIOIEV);
+ gpiois = readb(pl061->base + GPIOIS);
+ gpioibe = readb(pl061->base + GPIOIBE);
+
+ if (trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) {
+ bool polarity = trigger & IRQ_TYPE_LEVEL_HIGH;
+
+ /* Disable edge detection */
+ gpioibe &= ~bit;
+ /* Enable level detection */
+ gpiois |= bit;
+ /* Select polarity */
+ if (polarity)
+ gpioiev |= bit;
+ else
+ gpioiev &= ~bit;
+ irq_set_handler_locked(d, handle_level_irq);
+ dev_dbg(gc->parent, "line %d: IRQ on %s level\n",
+ offset,
+ polarity ? "HIGH" : "LOW");
+ } else if ((trigger & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
+ /* Disable level detection */
+ gpiois &= ~bit;
+ /* Select both edges, setting this makes GPIOEV be ignored */
+ gpioibe |= bit;
+ irq_set_handler_locked(d, handle_edge_irq);
+ dev_dbg(gc->parent, "line %d: IRQ on both edges\n", offset);
+ } else if ((trigger & IRQ_TYPE_EDGE_RISING) ||
+ (trigger & IRQ_TYPE_EDGE_FALLING)) {
+ bool rising = trigger & IRQ_TYPE_EDGE_RISING;
+
+ /* Disable level detection */
+ gpiois &= ~bit;
+ /* Clear detection on both edges */
+ gpioibe &= ~bit;
+ /* Select edge */
+ if (rising)
+ gpioiev |= bit;
+ else
+ gpioiev &= ~bit;
+ irq_set_handler_locked(d, handle_edge_irq);
+ dev_dbg(gc->parent, "line %d: IRQ on %s edge\n",
+ offset,
+ rising ? "RISING" : "FALLING");
+ } else {
+ /* No trigger: disable everything */
+ gpiois &= ~bit;
+ gpioibe &= ~bit;
+ gpioiev &= ~bit;
+ irq_set_handler_locked(d, handle_bad_irq);
+ dev_warn(gc->parent, "no trigger selected for line %d\n",
+ offset);
+ }
+
+ writeb(gpiois, pl061->base + GPIOIS);
+ writeb(gpioibe, pl061->base + GPIOIBE);
+ writeb(gpioiev, pl061->base + GPIOIEV);
+
+ raw_spin_unlock_irqrestore(&pl061->lock, flags);
+
+ return 0;
+}
+
+static void pl061_irq_handler(struct irq_desc *desc)
+{
+ unsigned long pending;
+ int offset;
+ struct gpio_chip *gc = irq_desc_get_handler_data(desc);
+ struct pl061 *pl061 = gpiochip_get_data(gc);
+ struct irq_chip *irqchip = irq_desc_get_chip(desc);
+
+ chained_irq_enter(irqchip, desc);
+
+ pending = readb(pl061->base + GPIOMIS);
+ if (pending) {
+ for_each_set_bit(offset, &pending, PL061_GPIO_NR)
+ generic_handle_domain_irq(gc->irq.domain,
+ 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 *pl061 = gpiochip_get_data(gc);
+ u8 mask = BIT(irqd_to_hwirq(d) % PL061_GPIO_NR);
+ u8 gpioie;
+
+ raw_spin_lock(&pl061->lock);
+ gpioie = readb(pl061->base + GPIOIE) & ~mask;
+ writeb(gpioie, pl061->base + GPIOIE);
+ raw_spin_unlock(&pl061->lock);
+
+ gpiochip_disable_irq(gc, d->hwirq);
+}
+
+static void pl061_irq_unmask(struct irq_data *d)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct pl061 *pl061 = gpiochip_get_data(gc);
+ u8 mask = BIT(irqd_to_hwirq(d) % PL061_GPIO_NR);
+ u8 gpioie;
+
+ gpiochip_enable_irq(gc, d->hwirq);
+
+ raw_spin_lock(&pl061->lock);
+ gpioie = readb(pl061->base + GPIOIE) | mask;
+ writeb(gpioie, pl061->base + GPIOIE);
+ raw_spin_unlock(&pl061->lock);
+}
+
+/**
+ * pl061_irq_ack() - ACK an edge IRQ
+ * @d: IRQ data for this IRQ
+ *
+ * This gets called from the edge IRQ handler to ACK the edge IRQ
+ * in the GPIOIC (interrupt-clear) register. For level IRQs this is
+ * not needed: these go away when the level signal goes away.
+ */
+static void pl061_irq_ack(struct irq_data *d)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct pl061 *pl061 = gpiochip_get_data(gc);
+ u8 mask = BIT(irqd_to_hwirq(d) % PL061_GPIO_NR);
+
+ raw_spin_lock(&pl061->lock);
+ writeb(mask, pl061->base + GPIOIC);
+ raw_spin_unlock(&pl061->lock);
+}
+
+static int pl061_irq_set_wake(struct irq_data *d, unsigned int state)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct pl061 *pl061 = gpiochip_get_data(gc);
+
+ return irq_set_irq_wake(pl061->parent_irq, state);
+}
+
+static void pl061_irq_print_chip(struct irq_data *data, struct seq_file *p)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
+
+ seq_printf(p, dev_name(gc->parent));
+}
+
+static const struct irq_chip pl061_irq_chip = {
+ .irq_ack = pl061_irq_ack,
+ .irq_mask = pl061_irq_mask,
+ .irq_unmask = pl061_irq_unmask,
+ .irq_set_type = pl061_irq_type,
+ .irq_set_wake = pl061_irq_set_wake,
+ .irq_print_chip = pl061_irq_print_chip,
+ .flags = IRQCHIP_IMMUTABLE,
+ GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
+static int pl061_probe(struct amba_device *adev, const struct amba_id *id)
+{
+ struct device *dev = &adev->dev;
+ struct pl061 *pl061;
+ struct gpio_irq_chip *girq;
+ int ret, irq;
+
+ pl061 = devm_kzalloc(dev, sizeof(*pl061), GFP_KERNEL);
+ if (pl061 == NULL)
+ return -ENOMEM;
+
+ pl061->base = devm_ioremap_resource(dev, &adev->res);
+ if (IS_ERR(pl061->base))
+ return PTR_ERR(pl061->base);
+
+ raw_spin_lock_init(&pl061->lock);
+ pl061->gc.request = gpiochip_generic_request;
+ pl061->gc.free = gpiochip_generic_free;
+ pl061->gc.base = -1;
+ pl061->gc.get_direction = pl061_get_direction;
+ pl061->gc.direction_input = pl061_direction_input;
+ pl061->gc.direction_output = pl061_direction_output;
+ pl061->gc.get = pl061_get_value;
+ pl061->gc.set = pl061_set_value;
+ pl061->gc.ngpio = PL061_GPIO_NR;
+ pl061->gc.label = dev_name(dev);
+ pl061->gc.parent = dev;
+ pl061->gc.owner = THIS_MODULE;
+
+ /*
+ * irq_chip support
+ */
+ writeb(0, pl061->base + GPIOIE); /* disable irqs */
+ irq = adev->irq[0];
+ if (!irq)
+ dev_warn(&adev->dev, "IRQ support disabled\n");
+ pl061->parent_irq = irq;
+
+ girq = &pl061->gc.irq;
+ gpio_irq_chip_set_chip(girq, &pl061_irq_chip);
+ girq->parent_handler = pl061_irq_handler;
+ girq->num_parents = 1;
+ girq->parents = devm_kcalloc(dev, 1, sizeof(*girq->parents),
+ GFP_KERNEL);
+ if (!girq->parents)
+ return -ENOMEM;
+ girq->parents[0] = irq;
+ girq->default_type = IRQ_TYPE_NONE;
+ girq->handler = handle_bad_irq;
+
+ ret = devm_gpiochip_add_data(dev, &pl061->gc, pl061);
+ if (ret)
+ return ret;
+
+ amba_set_drvdata(adev, pl061);
+ dev_info(dev, "PL061 GPIO chip registered\n");
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int pl061_suspend(struct device *dev)
+{
+ struct pl061 *pl061 = dev_get_drvdata(dev);
+ int offset;
+
+ pl061->csave_regs.gpio_data = 0;
+ pl061->csave_regs.gpio_dir = readb(pl061->base + GPIODIR);
+ pl061->csave_regs.gpio_is = readb(pl061->base + GPIOIS);
+ pl061->csave_regs.gpio_ibe = readb(pl061->base + GPIOIBE);
+ pl061->csave_regs.gpio_iev = readb(pl061->base + GPIOIEV);
+ pl061->csave_regs.gpio_ie = readb(pl061->base + GPIOIE);
+
+ for (offset = 0; offset < PL061_GPIO_NR; offset++) {
+ if (pl061->csave_regs.gpio_dir & (BIT(offset)))
+ pl061->csave_regs.gpio_data |=
+ pl061_get_value(&pl061->gc, offset) << offset;
+ }
+
+ return 0;
+}
+
+static int pl061_resume(struct device *dev)
+{
+ struct pl061 *pl061 = dev_get_drvdata(dev);
+ int offset;
+
+ for (offset = 0; offset < PL061_GPIO_NR; offset++) {
+ if (pl061->csave_regs.gpio_dir & (BIT(offset)))
+ pl061_direction_output(&pl061->gc, offset,
+ pl061->csave_regs.gpio_data &
+ (BIT(offset)));
+ else
+ pl061_direction_input(&pl061->gc, offset);
+ }
+
+ writeb(pl061->csave_regs.gpio_is, pl061->base + GPIOIS);
+ writeb(pl061->csave_regs.gpio_ibe, pl061->base + GPIOIBE);
+ writeb(pl061->csave_regs.gpio_iev, pl061->base + GPIOIEV);
+ writeb(pl061->csave_regs.gpio_ie, pl061->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 const 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,
+};
+module_amba_driver(pl061_gpio_driver);
+
+MODULE_LICENSE("GPL v2");