linux/drivers/gpio/gpio-visconti.c
Linus Walleij 5cf3e019a4 gpio: visconti: Convert to immutable irq_chip
Convert the driver to immutable irq-chip with a bit of
intuition.

The driver is for a hierarchical chip so some extra care
needs to be taken to introduce two new callbacks.

Cc: Marc Zyngier <maz@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2023-03-23 14:31:18 +01:00

233 lines
5.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Toshiba Visconti GPIO Support
*
* (C) Copyright 2020 Toshiba Electronic Devices & Storage Corporation
* (C) Copyright 2020 TOSHIBA CORPORATION
*
* Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
*/
#include <linux/gpio/driver.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/seq_file.h>
#include <linux/bitops.h>
/* register offset */
#define GPIO_DIR 0x00
#define GPIO_IDATA 0x08
#define GPIO_ODATA 0x10
#define GPIO_OSET 0x18
#define GPIO_OCLR 0x20
#define GPIO_INTMODE 0x30
#define BASE_HW_IRQ 24
struct visconti_gpio {
void __iomem *base;
spinlock_t lock; /* protect gpio register */
struct gpio_chip gpio_chip;
struct device *dev;
};
static int visconti_gpio_irq_set_type(struct irq_data *d, unsigned int type)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct visconti_gpio *priv = gpiochip_get_data(gc);
u32 offset = irqd_to_hwirq(d);
u32 bit = BIT(offset);
u32 intc_type = IRQ_TYPE_EDGE_RISING;
u32 intmode, odata;
int ret = 0;
unsigned long flags;
spin_lock_irqsave(&priv->lock, flags);
odata = readl(priv->base + GPIO_ODATA);
intmode = readl(priv->base + GPIO_INTMODE);
switch (type) {
case IRQ_TYPE_EDGE_RISING:
odata &= ~bit;
intmode &= ~bit;
break;
case IRQ_TYPE_EDGE_FALLING:
odata |= bit;
intmode &= ~bit;
break;
case IRQ_TYPE_EDGE_BOTH:
intmode |= bit;
break;
case IRQ_TYPE_LEVEL_HIGH:
intc_type = IRQ_TYPE_LEVEL_HIGH;
odata &= ~bit;
intmode &= ~bit;
break;
case IRQ_TYPE_LEVEL_LOW:
intc_type = IRQ_TYPE_LEVEL_HIGH;
odata |= bit;
intmode &= ~bit;
break;
default:
ret = -EINVAL;
goto err;
}
writel(odata, priv->base + GPIO_ODATA);
writel(intmode, priv->base + GPIO_INTMODE);
irq_set_irq_type(offset, intc_type);
ret = irq_chip_set_type_parent(d, type);
err:
spin_unlock_irqrestore(&priv->lock, flags);
return ret;
}
static int visconti_gpio_child_to_parent_hwirq(struct gpio_chip *gc,
unsigned int child,
unsigned int child_type,
unsigned int *parent,
unsigned int *parent_type)
{
/* Interrupts 0..15 mapped to interrupts 24..39 on the GIC */
if (child < 16) {
/* All these interrupts are level high in the CPU */
*parent_type = IRQ_TYPE_LEVEL_HIGH;
*parent = child + BASE_HW_IRQ;
return 0;
}
return -EINVAL;
}
static int visconti_gpio_populate_parent_fwspec(struct gpio_chip *chip,
union gpio_irq_fwspec *gfwspec,
unsigned int parent_hwirq,
unsigned int parent_type)
{
struct irq_fwspec *fwspec = &gfwspec->fwspec;
fwspec->fwnode = chip->irq.parent_domain->fwnode;
fwspec->param_count = 3;
fwspec->param[0] = 0;
fwspec->param[1] = parent_hwirq;
fwspec->param[2] = parent_type;
return 0;
}
static void visconti_gpio_mask_irq(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
irq_chip_mask_parent(d);
gpiochip_disable_irq(gc, irqd_to_hwirq(d));
}
static void visconti_gpio_unmask_irq(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
gpiochip_enable_irq(gc, irqd_to_hwirq(d));
irq_chip_unmask_parent(d);
}
static void visconti_gpio_irq_print_chip(struct irq_data *d, struct seq_file *p)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct visconti_gpio *priv = gpiochip_get_data(gc);
seq_printf(p, dev_name(priv->dev));
}
static const struct irq_chip visconti_gpio_irq_chip = {
.irq_mask = visconti_gpio_mask_irq,
.irq_unmask = visconti_gpio_unmask_irq,
.irq_eoi = irq_chip_eoi_parent,
.irq_set_type = visconti_gpio_irq_set_type,
.irq_print_chip = visconti_gpio_irq_print_chip,
.flags = IRQCHIP_SET_TYPE_MASKED | IRQCHIP_MASK_ON_SUSPEND |
IRQCHIP_IMMUTABLE,
GPIOCHIP_IRQ_RESOURCE_HELPERS,
};
static int visconti_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct visconti_gpio *priv;
struct gpio_irq_chip *girq;
struct irq_domain *parent;
struct device_node *irq_parent;
int ret;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
spin_lock_init(&priv->lock);
priv->dev = dev;
priv->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(priv->base))
return PTR_ERR(priv->base);
irq_parent = of_irq_find_parent(dev->of_node);
if (!irq_parent) {
dev_err(dev, "No IRQ parent node\n");
return -ENODEV;
}
parent = irq_find_host(irq_parent);
of_node_put(irq_parent);
if (!parent) {
dev_err(dev, "No IRQ parent domain\n");
return -ENODEV;
}
ret = bgpio_init(&priv->gpio_chip, dev, 4,
priv->base + GPIO_IDATA,
priv->base + GPIO_OSET,
priv->base + GPIO_OCLR,
priv->base + GPIO_DIR,
NULL,
0);
if (ret) {
dev_err(dev, "unable to init generic GPIO\n");
return ret;
}
girq = &priv->gpio_chip.irq;
gpio_irq_chip_set_chip(girq, &visconti_gpio_irq_chip);
girq->fwnode = of_node_to_fwnode(dev->of_node);
girq->parent_domain = parent;
girq->child_to_parent_hwirq = visconti_gpio_child_to_parent_hwirq;
girq->populate_parent_alloc_arg = visconti_gpio_populate_parent_fwspec;
girq->default_type = IRQ_TYPE_NONE;
girq->handler = handle_level_irq;
return devm_gpiochip_add_data(dev, &priv->gpio_chip, priv);
}
static const struct of_device_id visconti_gpio_of_match[] = {
{ .compatible = "toshiba,gpio-tmpv7708", },
{ /* end of table */ }
};
MODULE_DEVICE_TABLE(of, visconti_gpio_of_match);
static struct platform_driver visconti_gpio_driver = {
.probe = visconti_gpio_probe,
.driver = {
.name = "visconti_gpio",
.of_match_table = visconti_gpio_of_match,
}
};
module_platform_driver(visconti_gpio_driver);
MODULE_AUTHOR("Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>");
MODULE_DESCRIPTION("Toshiba Visconti GPIO Driver");
MODULE_LICENSE("GPL v2");