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path: root/drivers/gpio/gpio-ath79.c
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Diffstat (limited to 'drivers/gpio/gpio-ath79.c')
-rw-r--r--drivers/gpio/gpio-ath79.c331
1 files changed, 331 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-ath79.c b/drivers/gpio/gpio-ath79.c
new file mode 100644
index 000000000..0a553d676
--- /dev/null
+++ b/drivers/gpio/gpio-ath79.c
@@ -0,0 +1,331 @@
+/*
+ * Atheros AR71XX/AR724X/AR913X GPIO API support
+ *
+ * Copyright (C) 2015 Alban Bedel <albeu@free.fr>
+ * Copyright (C) 2010-2011 Jaiganesh Narayanan <jnarayanan@atheros.com>
+ * Copyright (C) 2008-2011 Gabor Juhos <juhosg@openwrt.org>
+ * Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <linux/gpio/driver.h>
+#include <linux/platform_data/gpio-ath79.h>
+#include <linux/of_device.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/irq.h>
+
+#define AR71XX_GPIO_REG_OE 0x00
+#define AR71XX_GPIO_REG_IN 0x04
+#define AR71XX_GPIO_REG_SET 0x0c
+#define AR71XX_GPIO_REG_CLEAR 0x10
+
+#define AR71XX_GPIO_REG_INT_ENABLE 0x14
+#define AR71XX_GPIO_REG_INT_TYPE 0x18
+#define AR71XX_GPIO_REG_INT_POLARITY 0x1c
+#define AR71XX_GPIO_REG_INT_PENDING 0x20
+#define AR71XX_GPIO_REG_INT_MASK 0x24
+
+struct ath79_gpio_ctrl {
+ struct gpio_chip gc;
+ void __iomem *base;
+ raw_spinlock_t lock;
+ unsigned long both_edges;
+};
+
+static struct ath79_gpio_ctrl *irq_data_to_ath79_gpio(struct irq_data *data)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
+
+ return container_of(gc, struct ath79_gpio_ctrl, gc);
+}
+
+static u32 ath79_gpio_read(struct ath79_gpio_ctrl *ctrl, unsigned reg)
+{
+ return readl(ctrl->base + reg);
+}
+
+static void ath79_gpio_write(struct ath79_gpio_ctrl *ctrl,
+ unsigned reg, u32 val)
+{
+ writel(val, ctrl->base + reg);
+}
+
+static bool ath79_gpio_update_bits(
+ struct ath79_gpio_ctrl *ctrl, unsigned reg, u32 mask, u32 bits)
+{
+ u32 old_val, new_val;
+
+ old_val = ath79_gpio_read(ctrl, reg);
+ new_val = (old_val & ~mask) | (bits & mask);
+
+ if (new_val != old_val)
+ ath79_gpio_write(ctrl, reg, new_val);
+
+ return new_val != old_val;
+}
+
+static void ath79_gpio_irq_unmask(struct irq_data *data)
+{
+ struct ath79_gpio_ctrl *ctrl = irq_data_to_ath79_gpio(data);
+ u32 mask = BIT(irqd_to_hwirq(data));
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&ctrl->lock, flags);
+ ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_MASK, mask, mask);
+ raw_spin_unlock_irqrestore(&ctrl->lock, flags);
+}
+
+static void ath79_gpio_irq_mask(struct irq_data *data)
+{
+ struct ath79_gpio_ctrl *ctrl = irq_data_to_ath79_gpio(data);
+ u32 mask = BIT(irqd_to_hwirq(data));
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&ctrl->lock, flags);
+ ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_MASK, mask, 0);
+ raw_spin_unlock_irqrestore(&ctrl->lock, flags);
+}
+
+static void ath79_gpio_irq_enable(struct irq_data *data)
+{
+ struct ath79_gpio_ctrl *ctrl = irq_data_to_ath79_gpio(data);
+ u32 mask = BIT(irqd_to_hwirq(data));
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&ctrl->lock, flags);
+ ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_ENABLE, mask, mask);
+ ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_MASK, mask, mask);
+ raw_spin_unlock_irqrestore(&ctrl->lock, flags);
+}
+
+static void ath79_gpio_irq_disable(struct irq_data *data)
+{
+ struct ath79_gpio_ctrl *ctrl = irq_data_to_ath79_gpio(data);
+ u32 mask = BIT(irqd_to_hwirq(data));
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&ctrl->lock, flags);
+ ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_MASK, mask, 0);
+ ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_ENABLE, mask, 0);
+ raw_spin_unlock_irqrestore(&ctrl->lock, flags);
+}
+
+static int ath79_gpio_irq_set_type(struct irq_data *data,
+ unsigned int flow_type)
+{
+ struct ath79_gpio_ctrl *ctrl = irq_data_to_ath79_gpio(data);
+ u32 mask = BIT(irqd_to_hwirq(data));
+ u32 type = 0, polarity = 0;
+ unsigned long flags;
+ bool disabled;
+
+ switch (flow_type) {
+ case IRQ_TYPE_EDGE_RISING:
+ polarity |= mask;
+ case IRQ_TYPE_EDGE_FALLING:
+ case IRQ_TYPE_EDGE_BOTH:
+ break;
+
+ case IRQ_TYPE_LEVEL_HIGH:
+ polarity |= mask;
+ /* fall through */
+ case IRQ_TYPE_LEVEL_LOW:
+ type |= mask;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ raw_spin_lock_irqsave(&ctrl->lock, flags);
+
+ if (flow_type == IRQ_TYPE_EDGE_BOTH) {
+ ctrl->both_edges |= mask;
+ polarity = ~ath79_gpio_read(ctrl, AR71XX_GPIO_REG_IN);
+ } else {
+ ctrl->both_edges &= ~mask;
+ }
+
+ /* As the IRQ configuration can't be loaded atomically we
+ * have to disable the interrupt while the configuration state
+ * is invalid.
+ */
+ disabled = ath79_gpio_update_bits(
+ ctrl, AR71XX_GPIO_REG_INT_ENABLE, mask, 0);
+
+ ath79_gpio_update_bits(
+ ctrl, AR71XX_GPIO_REG_INT_TYPE, mask, type);
+ ath79_gpio_update_bits(
+ ctrl, AR71XX_GPIO_REG_INT_POLARITY, mask, polarity);
+
+ if (disabled)
+ ath79_gpio_update_bits(
+ ctrl, AR71XX_GPIO_REG_INT_ENABLE, mask, mask);
+
+ raw_spin_unlock_irqrestore(&ctrl->lock, flags);
+
+ return 0;
+}
+
+static struct irq_chip ath79_gpio_irqchip = {
+ .name = "gpio-ath79",
+ .irq_enable = ath79_gpio_irq_enable,
+ .irq_disable = ath79_gpio_irq_disable,
+ .irq_mask = ath79_gpio_irq_mask,
+ .irq_unmask = ath79_gpio_irq_unmask,
+ .irq_set_type = ath79_gpio_irq_set_type,
+};
+
+static void ath79_gpio_irq_handler(struct irq_desc *desc)
+{
+ struct gpio_chip *gc = irq_desc_get_handler_data(desc);
+ struct irq_chip *irqchip = irq_desc_get_chip(desc);
+ struct ath79_gpio_ctrl *ctrl =
+ container_of(gc, struct ath79_gpio_ctrl, gc);
+ unsigned long flags, pending;
+ u32 both_edges, state;
+ int irq;
+
+ chained_irq_enter(irqchip, desc);
+
+ raw_spin_lock_irqsave(&ctrl->lock, flags);
+
+ pending = ath79_gpio_read(ctrl, AR71XX_GPIO_REG_INT_PENDING);
+
+ /* Update the polarity of the both edges irqs */
+ both_edges = ctrl->both_edges & pending;
+ if (both_edges) {
+ state = ath79_gpio_read(ctrl, AR71XX_GPIO_REG_IN);
+ ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_POLARITY,
+ both_edges, ~state);
+ }
+
+ raw_spin_unlock_irqrestore(&ctrl->lock, flags);
+
+ if (pending) {
+ for_each_set_bit(irq, &pending, gc->ngpio)
+ generic_handle_irq(
+ irq_linear_revmap(gc->irq.domain, irq));
+ }
+
+ chained_irq_exit(irqchip, desc);
+}
+
+static const struct of_device_id ath79_gpio_of_match[] = {
+ { .compatible = "qca,ar7100-gpio" },
+ { .compatible = "qca,ar9340-gpio" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ath79_gpio_of_match);
+
+static int ath79_gpio_probe(struct platform_device *pdev)
+{
+ struct ath79_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
+ struct device_node *np = pdev->dev.of_node;
+ struct ath79_gpio_ctrl *ctrl;
+ struct resource *res;
+ u32 ath79_gpio_count;
+ bool oe_inverted;
+ int err;
+
+ ctrl = devm_kzalloc(&pdev->dev, sizeof(*ctrl), GFP_KERNEL);
+ if (!ctrl)
+ return -ENOMEM;
+ platform_set_drvdata(pdev, ctrl);
+
+ if (np) {
+ err = of_property_read_u32(np, "ngpios", &ath79_gpio_count);
+ if (err) {
+ dev_err(&pdev->dev, "ngpios property is not valid\n");
+ return err;
+ }
+ oe_inverted = of_device_is_compatible(np, "qca,ar9340-gpio");
+ } else if (pdata) {
+ ath79_gpio_count = pdata->ngpios;
+ oe_inverted = pdata->oe_inverted;
+ } else {
+ dev_err(&pdev->dev, "No DT node or platform data found\n");
+ return -EINVAL;
+ }
+
+ if (ath79_gpio_count >= 32) {
+ dev_err(&pdev->dev, "ngpios must be less than 32\n");
+ return -EINVAL;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -EINVAL;
+ ctrl->base = devm_ioremap_nocache(
+ &pdev->dev, res->start, resource_size(res));
+ if (!ctrl->base)
+ return -ENOMEM;
+
+ raw_spin_lock_init(&ctrl->lock);
+ err = bgpio_init(&ctrl->gc, &pdev->dev, 4,
+ ctrl->base + AR71XX_GPIO_REG_IN,
+ ctrl->base + AR71XX_GPIO_REG_SET,
+ ctrl->base + AR71XX_GPIO_REG_CLEAR,
+ oe_inverted ? NULL : ctrl->base + AR71XX_GPIO_REG_OE,
+ oe_inverted ? ctrl->base + AR71XX_GPIO_REG_OE : NULL,
+ 0);
+ if (err) {
+ dev_err(&pdev->dev, "bgpio_init failed\n");
+ return err;
+ }
+ /* Use base 0 to stay compatible with legacy platforms */
+ ctrl->gc.base = 0;
+
+ err = gpiochip_add_data(&ctrl->gc, ctrl);
+ if (err) {
+ dev_err(&pdev->dev,
+ "cannot add AR71xx GPIO chip, error=%d", err);
+ return err;
+ }
+
+ if (np && !of_property_read_bool(np, "interrupt-controller"))
+ return 0;
+
+ err = gpiochip_irqchip_add(&ctrl->gc, &ath79_gpio_irqchip, 0,
+ handle_simple_irq, IRQ_TYPE_NONE);
+ if (err) {
+ dev_err(&pdev->dev, "failed to add gpiochip_irqchip\n");
+ goto gpiochip_remove;
+ }
+
+ gpiochip_set_chained_irqchip(&ctrl->gc, &ath79_gpio_irqchip,
+ platform_get_irq(pdev, 0),
+ ath79_gpio_irq_handler);
+
+ return 0;
+
+gpiochip_remove:
+ gpiochip_remove(&ctrl->gc);
+ return err;
+}
+
+static int ath79_gpio_remove(struct platform_device *pdev)
+{
+ struct ath79_gpio_ctrl *ctrl = platform_get_drvdata(pdev);
+
+ gpiochip_remove(&ctrl->gc);
+ return 0;
+}
+
+static struct platform_driver ath79_gpio_driver = {
+ .driver = {
+ .name = "ath79-gpio",
+ .of_match_table = ath79_gpio_of_match,
+ },
+ .probe = ath79_gpio_probe,
+ .remove = ath79_gpio_remove,
+};
+
+module_platform_driver(ath79_gpio_driver);
+
+MODULE_DESCRIPTION("Atheros AR71XX/AR724X/AR913X GPIO API support");
+MODULE_LICENSE("GPL v2");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-27 03:45:04 +0000