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authorAlban Bedel <albeu@free.fr>2016-01-28 20:44:32 +0100
committerLinus Walleij <linus.walleij@linaro.org>2016-02-10 11:15:24 +0100
commit2b8f89e19b6d83d97019358328cbed22bbb0505e (patch)
tree14ee908f82178fd98737beafef94a40141e90dc7
parent2f890cf0dfe421ecd2095d8cabb89e7207b499ee (diff)
gpio: ath79: Add support for the interrupt controller
Add support for the interrupt controller using GPIOLIB_IRQCHIP. Both edges isn't supported by the chip and has to be emulated by switching the polarity on each interrupt. Signed-off-by: Alban Bedel <albeu@free.fr> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
-rw-r--r--drivers/gpio/Kconfig1
-rw-r--r--drivers/gpio/gpio-ath79.c205
2 files changed, 206 insertions, 0 deletions
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 3c1bb917dd72..f52b25964bc6 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -131,6 +131,7 @@ config GPIO_ATH79
default y if ATH79
depends on ATH79 || COMPILE_TEST
select GPIO_GENERIC
+ select GPIOLIB_IRQCHIP
help
Select this option to enable GPIO driver for
Atheros AR71XX/AR724X/AR913X SoC devices.
diff --git a/drivers/gpio/gpio-ath79.c b/drivers/gpio/gpio-ath79.c
index 6b157925e16e..0d94c0bd764a 100644
--- a/drivers/gpio/gpio-ath79.c
+++ b/drivers/gpio/gpio-ath79.c
@@ -15,18 +15,205 @@
#include <linux/gpio/driver.h>
#include <linux/platform_data/gpio-ath79.h>
#include <linux/of_device.h>
+#include <linux/interrupt.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;
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)
+{
+ return 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;
+
+ spin_lock_irqsave(&ctrl->lock, flags);
+ ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_MASK, mask, mask);
+ 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;
+
+ spin_lock_irqsave(&ctrl->lock, flags);
+ ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_MASK, mask, 0);
+ 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;
+
+ 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);
+ 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;
+
+ 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);
+ 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;
+ case IRQ_TYPE_LEVEL_LOW:
+ type |= mask;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ 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);
+
+ 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);
+
+ 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);
+ }
+
+ spin_unlock_irqrestore(&ctrl->lock, flags);
+
+ if (pending) {
+ for_each_set_bit(irq, &pending, gc->ngpio)
+ generic_handle_irq(
+ irq_linear_revmap(gc->irqdomain, irq));
+ }
+
+ chained_irq_exit(irqchip, desc);
+}
+
static const struct of_device_id ath79_gpio_of_match[] = {
{ .compatible = "qca,ar7100-gpio" },
{ .compatible = "qca,ar9340-gpio" },
@@ -95,7 +282,25 @@ static int ath79_gpio_probe(struct platform_device *pdev)
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)