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path: root/drivers/gpio/gpio-zx.c
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-rw-r--r--drivers/gpio/gpio-zx.c289
1 files changed, 289 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-zx.c b/drivers/gpio/gpio-zx.c
new file mode 100644
index 000000000..64bfb7227
--- /dev/null
+++ b/drivers/gpio/gpio-zx.c
@@ -0,0 +1,289 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ZTE ZX296702 GPIO driver
+ *
+ * Author: Jun Nie <jun.nie@linaro.org>
+ *
+ * Copyright (C) 2015 Linaro Ltd.
+ */
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/gpio/driver.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#define ZX_GPIO_DIR 0x00
+#define ZX_GPIO_IVE 0x04
+#define ZX_GPIO_IV 0x08
+#define ZX_GPIO_IEP 0x0C
+#define ZX_GPIO_IEN 0x10
+#define ZX_GPIO_DI 0x14
+#define ZX_GPIO_DO1 0x18
+#define ZX_GPIO_DO0 0x1C
+#define ZX_GPIO_DO 0x20
+
+#define ZX_GPIO_IM 0x28
+#define ZX_GPIO_IE 0x2C
+
+#define ZX_GPIO_MIS 0x30
+#define ZX_GPIO_IC 0x34
+
+#define ZX_GPIO_NR 16
+
+struct zx_gpio {
+ raw_spinlock_t lock;
+
+ void __iomem *base;
+ struct gpio_chip gc;
+};
+
+static int zx_direction_input(struct gpio_chip *gc, unsigned offset)
+{
+ struct zx_gpio *chip = gpiochip_get_data(gc);
+ unsigned long flags;
+ u16 gpiodir;
+
+ if (offset >= gc->ngpio)
+ return -EINVAL;
+
+ raw_spin_lock_irqsave(&chip->lock, flags);
+ gpiodir = readw_relaxed(chip->base + ZX_GPIO_DIR);
+ gpiodir &= ~BIT(offset);
+ writew_relaxed(gpiodir, chip->base + ZX_GPIO_DIR);
+ raw_spin_unlock_irqrestore(&chip->lock, flags);
+
+ return 0;
+}
+
+static int zx_direction_output(struct gpio_chip *gc, unsigned offset,
+ int value)
+{
+ struct zx_gpio *chip = gpiochip_get_data(gc);
+ unsigned long flags;
+ u16 gpiodir;
+
+ if (offset >= gc->ngpio)
+ return -EINVAL;
+
+ raw_spin_lock_irqsave(&chip->lock, flags);
+ gpiodir = readw_relaxed(chip->base + ZX_GPIO_DIR);
+ gpiodir |= BIT(offset);
+ writew_relaxed(gpiodir, chip->base + ZX_GPIO_DIR);
+
+ if (value)
+ writew_relaxed(BIT(offset), chip->base + ZX_GPIO_DO1);
+ else
+ writew_relaxed(BIT(offset), chip->base + ZX_GPIO_DO0);
+ raw_spin_unlock_irqrestore(&chip->lock, flags);
+
+ return 0;
+}
+
+static int zx_get_value(struct gpio_chip *gc, unsigned offset)
+{
+ struct zx_gpio *chip = gpiochip_get_data(gc);
+
+ return !!(readw_relaxed(chip->base + ZX_GPIO_DI) & BIT(offset));
+}
+
+static void zx_set_value(struct gpio_chip *gc, unsigned offset, int value)
+{
+ struct zx_gpio *chip = gpiochip_get_data(gc);
+
+ if (value)
+ writew_relaxed(BIT(offset), chip->base + ZX_GPIO_DO1);
+ else
+ writew_relaxed(BIT(offset), chip->base + ZX_GPIO_DO0);
+}
+
+static int zx_irq_type(struct irq_data *d, unsigned trigger)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct zx_gpio *chip = gpiochip_get_data(gc);
+ int offset = irqd_to_hwirq(d);
+ unsigned long flags;
+ u16 gpiois, gpioi_epos, gpioi_eneg, gpioiev;
+ u16 bit = BIT(offset);
+
+ if (offset < 0 || offset >= ZX_GPIO_NR)
+ return -EINVAL;
+
+ raw_spin_lock_irqsave(&chip->lock, flags);
+
+ gpioiev = readw_relaxed(chip->base + ZX_GPIO_IV);
+ gpiois = readw_relaxed(chip->base + ZX_GPIO_IVE);
+ gpioi_epos = readw_relaxed(chip->base + ZX_GPIO_IEP);
+ gpioi_eneg = readw_relaxed(chip->base + ZX_GPIO_IEN);
+
+ if (trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) {
+ gpiois |= bit;
+ if (trigger & IRQ_TYPE_LEVEL_HIGH)
+ gpioiev |= bit;
+ else
+ gpioiev &= ~bit;
+ } else
+ gpiois &= ~bit;
+
+ if ((trigger & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
+ gpioi_epos |= bit;
+ gpioi_eneg |= bit;
+ } else {
+ if (trigger & IRQ_TYPE_EDGE_RISING) {
+ gpioi_epos |= bit;
+ gpioi_eneg &= ~bit;
+ } else if (trigger & IRQ_TYPE_EDGE_FALLING) {
+ gpioi_eneg |= bit;
+ gpioi_epos &= ~bit;
+ }
+ }
+
+ writew_relaxed(gpiois, chip->base + ZX_GPIO_IVE);
+ writew_relaxed(gpioi_epos, chip->base + ZX_GPIO_IEP);
+ writew_relaxed(gpioi_eneg, chip->base + ZX_GPIO_IEN);
+ writew_relaxed(gpioiev, chip->base + ZX_GPIO_IV);
+ raw_spin_unlock_irqrestore(&chip->lock, flags);
+
+ return 0;
+}
+
+static void zx_irq_handler(struct irq_desc *desc)
+{
+ unsigned long pending;
+ int offset;
+ struct gpio_chip *gc = irq_desc_get_handler_data(desc);
+ struct zx_gpio *chip = gpiochip_get_data(gc);
+ struct irq_chip *irqchip = irq_desc_get_chip(desc);
+
+ chained_irq_enter(irqchip, desc);
+
+ pending = readw_relaxed(chip->base + ZX_GPIO_MIS);
+ writew_relaxed(pending, chip->base + ZX_GPIO_IC);
+ if (pending) {
+ for_each_set_bit(offset, &pending, ZX_GPIO_NR)
+ generic_handle_irq(irq_find_mapping(gc->irq.domain,
+ offset));
+ }
+
+ chained_irq_exit(irqchip, desc);
+}
+
+static void zx_irq_mask(struct irq_data *d)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct zx_gpio *chip = gpiochip_get_data(gc);
+ u16 mask = BIT(irqd_to_hwirq(d) % ZX_GPIO_NR);
+ u16 gpioie;
+
+ raw_spin_lock(&chip->lock);
+ gpioie = readw_relaxed(chip->base + ZX_GPIO_IM) | mask;
+ writew_relaxed(gpioie, chip->base + ZX_GPIO_IM);
+ gpioie = readw_relaxed(chip->base + ZX_GPIO_IE) & ~mask;
+ writew_relaxed(gpioie, chip->base + ZX_GPIO_IE);
+ raw_spin_unlock(&chip->lock);
+}
+
+static void zx_irq_unmask(struct irq_data *d)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct zx_gpio *chip = gpiochip_get_data(gc);
+ u16 mask = BIT(irqd_to_hwirq(d) % ZX_GPIO_NR);
+ u16 gpioie;
+
+ raw_spin_lock(&chip->lock);
+ gpioie = readw_relaxed(chip->base + ZX_GPIO_IM) & ~mask;
+ writew_relaxed(gpioie, chip->base + ZX_GPIO_IM);
+ gpioie = readw_relaxed(chip->base + ZX_GPIO_IE) | mask;
+ writew_relaxed(gpioie, chip->base + ZX_GPIO_IE);
+ raw_spin_unlock(&chip->lock);
+}
+
+static struct irq_chip zx_irqchip = {
+ .name = "zx-gpio",
+ .irq_mask = zx_irq_mask,
+ .irq_unmask = zx_irq_unmask,
+ .irq_set_type = zx_irq_type,
+};
+
+static int zx_gpio_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct zx_gpio *chip;
+ struct gpio_irq_chip *girq;
+ int irq, id, ret;
+
+ chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ chip->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(chip->base))
+ return PTR_ERR(chip->base);
+
+ id = of_alias_get_id(dev->of_node, "gpio");
+
+ raw_spin_lock_init(&chip->lock);
+ chip->gc.request = gpiochip_generic_request;
+ chip->gc.free = gpiochip_generic_free;
+ chip->gc.direction_input = zx_direction_input;
+ chip->gc.direction_output = zx_direction_output;
+ chip->gc.get = zx_get_value;
+ chip->gc.set = zx_set_value;
+ chip->gc.base = ZX_GPIO_NR * id;
+ chip->gc.ngpio = ZX_GPIO_NR;
+ chip->gc.label = dev_name(dev);
+ chip->gc.parent = dev;
+ chip->gc.owner = THIS_MODULE;
+
+ /*
+ * irq_chip support
+ */
+ writew_relaxed(0xffff, chip->base + ZX_GPIO_IM);
+ writew_relaxed(0, chip->base + ZX_GPIO_IE);
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+ girq = &chip->gc.irq;
+ girq->chip = &zx_irqchip;
+ girq->parent_handler = zx_irq_handler;
+ girq->num_parents = 1;
+ girq->parents = devm_kcalloc(&pdev->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_simple_irq;
+
+ ret = gpiochip_add_data(&chip->gc, chip);
+ if (ret)
+ return ret;
+
+ platform_set_drvdata(pdev, chip);
+ dev_info(dev, "ZX GPIO chip registered\n");
+
+ return 0;
+}
+
+static const struct of_device_id zx_gpio_match[] = {
+ {
+ .compatible = "zte,zx296702-gpio",
+ },
+ { },
+};
+
+static struct platform_driver zx_gpio_driver = {
+ .probe = zx_gpio_probe,
+ .driver = {
+ .name = "zx_gpio",
+ .of_match_table = of_match_ptr(zx_gpio_match),
+ },
+};
+builtin_platform_driver(zx_gpio_driver)
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-30 12:39:14 +0000