1 files changed, 192 insertions, 72 deletions

diff --git a/drivers/gpio/gpio-ath79.c b/drivers/gpio/gpio-ath79.c
index d13dd133a907..c4f4cddc7c1a 100644
--- a/drivers/gpio/gpio-ath79.c
+++ b/drivers/gpio/gpio-ath79.c
@@ -1,12 +1,11 @@
 /*
  *  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>
  *
- *  Parts of this file are based on Atheros' 2.6.15/2.6.31 BSP
- *
  *  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.
@@ -15,118 +14,204 @@
 #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
 
-#include <asm/mach-ath79/ar71xx_regs.h>
+#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 chip;
+	struct gpio_chip gc;
 	void __iomem *base;
 	spinlock_t lock;
+	unsigned long both_edges;
 };
 
-static void ath79_gpio_set_value(struct gpio_chip *chip,
-				unsigned gpio, int value)
+static struct ath79_gpio_ctrl *irq_data_to_ath79_gpio(struct irq_data *data)
 {
-	struct ath79_gpio_ctrl *ctrl = gpiochip_get_data(chip);
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
 
-	if (value)
-		__raw_writel(BIT(gpio), ctrl->base + AR71XX_GPIO_REG_SET);
-	else
-		__raw_writel(BIT(gpio), ctrl->base + AR71XX_GPIO_REG_CLEAR);
+	return container_of(gc, struct ath79_gpio_ctrl, gc);
 }
 
-static int ath79_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
+static u32 ath79_gpio_read(struct ath79_gpio_ctrl *ctrl, unsigned reg)
 {
-	struct ath79_gpio_ctrl *ctrl = gpiochip_get_data(chip);
+	return readl(ctrl->base + reg);
+}
 
-	return (__raw_readl(ctrl->base + AR71XX_GPIO_REG_IN) >> gpio) & 1;
+static void ath79_gpio_write(struct ath79_gpio_ctrl *ctrl,
+			unsigned reg, u32 val)
+{
+	return writel(val, ctrl->base + reg);
 }
 
-static int ath79_gpio_direction_input(struct gpio_chip *chip,
-				       unsigned offset)
+static bool ath79_gpio_update_bits(
+	struct ath79_gpio_ctrl *ctrl, unsigned reg, u32 mask, u32 bits)
 {
-	struct ath79_gpio_ctrl *ctrl = gpiochip_get_data(chip);
+	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);
+}
 
-	__raw_writel(
-		__raw_readl(ctrl->base + AR71XX_GPIO_REG_OE) & ~BIT(offset),
-		ctrl->base + AR71XX_GPIO_REG_OE);
+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);
-
-	return 0;
 }
 
-static int ath79_gpio_direction_output(struct gpio_chip *chip,
-					unsigned offset, int value)
+static void ath79_gpio_irq_enable(struct irq_data *data)
 {
-	struct ath79_gpio_ctrl *ctrl = gpiochip_get_data(chip);
+	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);
+}
 
-	if (value)
-		__raw_writel(BIT(offset), ctrl->base + AR71XX_GPIO_REG_SET);
-	else
-		__raw_writel(BIT(offset), ctrl->base + AR71XX_GPIO_REG_CLEAR);
-
-	__raw_writel(
-		__raw_readl(ctrl->base + AR71XX_GPIO_REG_OE) | BIT(offset),
-		ctrl->base + AR71XX_GPIO_REG_OE);
+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);
-
-	return 0;
 }
 
-static int ar934x_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+static int ath79_gpio_irq_set_type(struct irq_data *data,
+				unsigned int flow_type)
 {
-	struct ath79_gpio_ctrl *ctrl = gpiochip_get_data(chip);
+	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);
 
-	__raw_writel(
-		__raw_readl(ctrl->base + AR71XX_GPIO_REG_OE) | BIT(offset),
-		ctrl->base + AR71XX_GPIO_REG_OE);
+	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 int ar934x_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
-					int value)
+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 ath79_gpio_ctrl *ctrl = gpiochip_get_data(chip);
-	unsigned long flags;
+	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);
 
-	if (value)
-		__raw_writel(BIT(offset), ctrl->base + AR71XX_GPIO_REG_SET);
-	else
-		__raw_writel(BIT(offset), ctrl->base + AR71XX_GPIO_REG_CLEAR);
+	pending = ath79_gpio_read(ctrl, AR71XX_GPIO_REG_INT_PENDING);
 
-	__raw_writel(
-		__raw_readl(ctrl->base + AR71XX_GPIO_REG_OE) & ~BIT(offset),
-		ctrl->base + AR71XX_GPIO_REG_OE);
+	/* 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);
 
-	return 0;
-}
+	if (pending) {
+		for_each_set_bit(irq, &pending, gc->ngpio)
+			generic_handle_irq(
+				irq_linear_revmap(gc->irqdomain, irq));
+	}
 
-static const struct gpio_chip ath79_gpio_chip = {
-	.label			= "ath79",
-	.get			= ath79_gpio_get_value,
-	.set			= ath79_gpio_set_value,
-	.direction_input	= ath79_gpio_direction_input,
-	.direction_output	= ath79_gpio_direction_output,
-	.base			= 0,
-};
+	chained_irq_exit(irqchip, desc);
+}
 
 static const struct of_device_id ath79_gpio_of_match[] = {
 	{ .compatible = "qca,ar7100-gpio" },
@@ -147,6 +232,7 @@ static int ath79_gpio_probe(struct platform_device *pdev)
 	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);
@@ -154,10 +240,6 @@ static int ath79_gpio_probe(struct platform_device *pdev)
 			dev_err(&pdev->dev, "ngpios property is not valid\n");
 			return err;
 		}
-		if (ath79_gpio_count >= 32) {
-			dev_err(&pdev->dev, "ngpios must be less than 32\n");
-			return -EINVAL;
-		}
 		oe_inverted = of_device_is_compatible(np, "qca,ar9340-gpio");
 	} else if (pdata) {
 		ath79_gpio_count = pdata->ngpios;
@@ -167,6 +249,11 @@ static int ath79_gpio_probe(struct platform_device *pdev)
 		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);
 	ctrl->base = devm_ioremap_nocache(
 		&pdev->dev, res->start, resource_size(res));
@@ -174,21 +261,53 @@ static int ath79_gpio_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	spin_lock_init(&ctrl->lock);
-	memcpy(&ctrl->chip, &ath79_gpio_chip, sizeof(ctrl->chip));
-	ctrl->chip.parent = &pdev->dev;
-	ctrl->chip.ngpio = ath79_gpio_count;
-	if (oe_inverted) {
-		ctrl->chip.direction_input = ar934x_gpio_direction_input;
-		ctrl->chip.direction_output = ar934x_gpio_direction_output;
+	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->chip, ctrl);
+	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;
 }
 
@@ -198,6 +317,7 @@ static struct platform_driver ath79_gpio_driver = {
 		.of_match_table	= ath79_gpio_of_match,
 	},
 	.probe = ath79_gpio_probe,
+	.remove = ath79_gpio_remove,
 };
 
 module_platform_driver(ath79_gpio_driver);