[PATCH v4 5/7] pinctrl: aramda-37xx: Add irqchip support

[gregory.clement@free-electrons.com (Gregory CLEMENT)]

Argh, I sill have the typo in the title of this patch! :(

If you are going to apply it could you fix it, else it will be fixed in
the next version.

Sorry,

Gregory

 
 On mer., avril 05 2017, Gregory CLEMENT <gregory.clement@free-electrons.com> wrote:

> The Armada 37xx SoCs can handle interrupt through GPIO. However it can
> only manage the edge ones.
>
> The way the interrupt are managed are classical so we can use the generic
> interrupt chip model.
>
> The only unusual "feature" is that many interrupts are connected to the
> parent interrupt controller. But we do not take advantage of this and use
> the chained irq with all of them.
>
> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
> ---
>  drivers/pinctrl/mvebu/pinctrl-armada-37xx.c | 221 +++++++++++++++++++++-
>  1 file changed, 221 insertions(+)
>
> diff --git a/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c b/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c
> index 5c96f5558310..7356516e0921 100644
> --- a/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c
> +++ b/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c
> @@ -13,7 +13,9 @@
>  #include <linux/gpio/driver.h>
>  #include <linux/mfd/syscon.h>
>  #include <linux/of.h>
> +#include <linux/of_address.h>
>  #include <linux/of_device.h>
> +#include <linux/of_irq.h>
>  #include <linux/pinctrl/pinconf-generic.h>
>  #include <linux/pinctrl/pinconf.h>
>  #include <linux/pinctrl/pinctrl.h>
> @@ -30,6 +32,11 @@
>  #define OUTPUT_CTL	0x20
>  #define SELECTION	0x30
>  
> +#define IRQ_EN		0x0
> +#define IRQ_POL		0x08
> +#define IRQ_STATUS	0x10
> +#define IRQ_WKUP	0x18
> +
>  #define NB_FUNCS 2
>  #define GPIO_PER_REG	32
>  
> @@ -75,9 +82,12 @@ struct armada_37xx_pmx_func {
>  
>  struct armada_37xx_pinctrl {
>  	struct regmap			*regmap;
> +	void __iomem			*base;
>  	const struct armada_37xx_pin_data	*data;
>  	struct device			*dev;
>  	struct gpio_chip		gpio_chip;
> +	struct irq_chip			irq_chip;
> +	spinlock_t			irq_lock;
>  	struct pinctrl_desc		pctl;
>  	struct pinctrl_dev		*pctl_dev;
>  	struct armada_37xx_pin_group	*groups;
> @@ -346,6 +356,14 @@ static int armada_37xx_pmx_set(struct pinctrl_dev *pctldev,
>  	return armada_37xx_pmx_set_by_name(pctldev, name, grp);
>  }
>  
> +static inline void armada_37xx_irq_update_reg(unsigned int *reg,
> +					  struct irq_data *d)
> +{
> +	int offset = irqd_to_hwirq(d);
> +
> +	armada_37xx_update_reg(reg, offset);
> +}
> +
>  static int armada_37xx_gpio_direction_input(struct gpio_chip *chip,
>  					    unsigned int offset)
>  {
> @@ -468,6 +486,206 @@ static const struct gpio_chip armada_37xx_gpiolib_chip = {
>  	.owner = THIS_MODULE,
>  };
>  
> +void armada_37xx_irq_ack(struct irq_data *d)
> +{
> +	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
> +	struct armada_37xx_pinctrl *info = gpiochip_get_data(chip);
> +	u32 reg = IRQ_STATUS, mask = d->mask;
> +	unsigned long flags;
> +
> +	armada_37xx_irq_update_reg(&reg, d);
> +	spin_lock_irqsave(&info->irq_lock, flags);
> +	writel(mask, info->base + reg);
> +	spin_unlock_irqrestore(&info->irq_lock, flags);
> +}
> +
> +void armada_37xx_irq_mask(struct irq_data *d)
> +{
> +	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
> +	struct armada_37xx_pinctrl *info = gpiochip_get_data(chip);
> +	u32 val, reg = IRQ_EN, mask = d->mask;
> +	unsigned long flags;
> +
> +	armada_37xx_irq_update_reg(&reg, d);
> +	spin_lock_irqsave(&info->irq_lock, flags);
> +	val = readl(info->base + reg);
> +	writel(val & ~mask, info->base + reg);
> +	spin_unlock_irqrestore(&info->irq_lock, flags);
> +}
> +
> +void armada_37xx_irq_unmask(struct irq_data *d)
> +{
> +	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
> +	struct armada_37xx_pinctrl *info = gpiochip_get_data(chip);
> +	u32 val, reg = IRQ_EN, mask = d->mask;
> +	unsigned long flags;
> +
> +	armada_37xx_irq_update_reg(&reg, d);
> +	spin_lock_irqsave(&info->irq_lock, flags);
> +	val = readl(info->base + reg);
> +	writel(val | mask, info->base + reg);
> +	spin_unlock_irqrestore(&info->irq_lock, flags);
> +}
> +
> +static int armada_37xx_irq_set_wake(struct irq_data *d, unsigned int on)
> +{
> +	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
> +	struct armada_37xx_pinctrl *info = gpiochip_get_data(chip);
> +	u32 val, reg = IRQ_WKUP, mask = d->mask;
> +	unsigned long flags;
> +
> +	armada_37xx_irq_update_reg(&reg, d);
> +	spin_lock_irqsave(&info->irq_lock, flags);
> +	val = readl(info->base + reg);
> +	if (on)
> +		val |= mask;
> +	else
> +		val &= ~mask;
> +	writel(val, info->base + reg);
> +	spin_unlock_irqrestore(&info->irq_lock, flags);
> +
> +	return 0;
> +}
> +
> +static int armada_37xx_irq_set_type(struct irq_data *d, unsigned int type)
> +{
> +	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
> +	struct armada_37xx_pinctrl *info = gpiochip_get_data(chip);
> +	u32 val, reg = IRQ_POL, mask = d->mask;
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&info->irq_lock, flags);
> +	armada_37xx_irq_update_reg(&reg, d);
> +	val = readl(info->base + reg);
> +	switch (type) {
> +	case IRQ_TYPE_EDGE_RISING:
> +		val &= ~mask;
> +		break;
> +	case IRQ_TYPE_EDGE_FALLING:
> +		val |= mask;
> +		break;
> +	default:
> +		spin_unlock_irqrestore(&info->irq_lock, flags);
> +		return -EINVAL;
> +	}
> +	writel(val, info->base + reg);
> +	spin_unlock_irqrestore(&info->irq_lock, flags);
> +
> +	return 0;
> +}
> +
> +
> +static void armada_37xx_irq_handler(struct irq_desc *desc)
> +{
> +	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
> +	struct irq_chip *chip = irq_desc_get_chip(desc);
> +	struct armada_37xx_pinctrl *info = gpiochip_get_data(gc);
> +	struct irq_domain *d = gc->irqdomain;
> +	int i;
> +
> +	chained_irq_enter(chip, desc);
> +	for (i = 0; i <= d->revmap_size / GPIO_PER_REG; i++) {
> +		u32 status;
> +		unsigned long flags;
> +
> +		spin_lock_irqsave(&info->irq_lock, flags);
> +		status = readl_relaxed(info->base + IRQ_STATUS + 4 * i);
> +		/* Manage only the interrupt that was enabled */
> +		status &= readl_relaxed(info->base + IRQ_EN + 4 * i);
> +		spin_unlock_irqrestore(&info->irq_lock, flags);
> +		while (status) {
> +			u32 hwirq = ffs(status) - 1;
> +			u32 virq = irq_find_mapping(d, hwirq +
> +						     i * GPIO_PER_REG);
> +
> +			generic_handle_irq(virq);
> +			status &= ~BIT(hwirq);
> +		}
> +	}
> +	chained_irq_exit(chip, desc);
> +}
> +
> +static int armada_37xx_irqchip_register(struct platform_device *pdev,
> +					struct armada_37xx_pinctrl *info)
> +{
> +	struct device_node *np = info->dev->of_node;
> +	int nrirqs = info->data->nr_pins;
> +	struct gpio_chip *gc = &info->gpio_chip;
> +	struct irq_chip *irqchip = &info->irq_chip;
> +	struct resource res;
> +	int ret = -ENODEV, i, nr_irq_parent;
> +
> +	for_each_child_of_node(info->dev->of_node, np) {
> +		if (of_find_property(np, "gpio-controller", NULL)) {
> +			ret = 0;
> +			break;
> +		}
> +	};
> +	if (ret)
> +		return ret;
> +
> +	nr_irq_parent = of_irq_count(np);
> +	spin_lock_init(&info->irq_lock);
> +
> +	if (!nr_irq_parent) {
> +		dev_err(&pdev->dev, "Invalid or no IRQ\n");
> +		return 0;
> +	}
> +
> +	if (of_address_to_resource(info->dev->of_node, 1, &res)) {
> +		dev_err(info->dev, "cannot find IO resource\n");
> +		return -ENOENT;
> +	}
> +
> +	info->base = devm_ioremap_resource(info->dev, &res);
> +	if (IS_ERR(info->base))
> +		return PTR_ERR(info->base);
> +
> +	irqchip->irq_ack = armada_37xx_irq_ack;
> +	irqchip->irq_mask = armada_37xx_irq_mask;
> +	irqchip->irq_unmask = armada_37xx_irq_unmask;
> +	irqchip->irq_set_wake = armada_37xx_irq_set_wake;
> +	irqchip->irq_set_type = armada_37xx_irq_set_type;
> +	irqchip->name = info->data->name;
> +
> +	ret = gpiochip_irqchip_add(gc, irqchip, 0,
> +				   handle_edge_irq, IRQ_TYPE_NONE);
> +	if (ret) {
> +		dev_info(&pdev->dev, "could not add irqchip\n");
> +		return ret;
> +	}
> +
> +	/*
> +	 * Many interrupts are connected to the parent interrupt
> +	 * controller. But we do not take advantage of this and use
> +	 * the chained irq with all of them.
> +	 */
> +	for (i = 0; i < nrirqs; i++) {
> +		struct irq_data *d = irq_get_irq_data(gc->irq_base + i);
> +
> +		/*
> +		 * The mask field is a "precomputed bitmask for
> +		 * accessing the chip registers" which was introduced
> +		 * for the generic irqchip framework. As we don't use
> +		 * this framework, we can reuse this field for our own
> +		 * usage.
> +		 */
> +		d->mask = BIT(i % GPIO_PER_REG);
> +	}
> +
> +	for (i = 0; i < nr_irq_parent; i++) {
> +		int irq = irq_of_parse_and_map(np, i);
> +
> +		if (irq < 0)
> +			continue;
> +
> +		gpiochip_set_chained_irqchip(gc, irqchip, irq,
> +					     armada_37xx_irq_handler);
> +	}
> +
> +	return 0;
> +}
> +
>  static int armada_37xx_gpiochip_register(struct platform_device *pdev,
>  					struct armada_37xx_pinctrl *info)
>  {
> @@ -496,6 +714,9 @@ static int armada_37xx_gpiochip_register(struct platform_device *pdev,
>  	ret = devm_gpiochip_add_data(&pdev->dev, gc, info);
>  	if (ret)
>  		return ret;
> +	ret = armada_37xx_irqchip_register(pdev, info);
> +	if (ret)
> +		return ret;
>  
>  	return 0;
>  }
> -- 
> git-series 0.9.1

-- 
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com