diff options
Diffstat (limited to 'drivers/gpio/gpio-visconti.c')
| -rw-r--r-- | drivers/gpio/gpio-visconti.c | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-visconti.c b/drivers/gpio/gpio-visconti.c new file mode 100644 index 000000000..5e108ba99 --- /dev/null +++ b/drivers/gpio/gpio-visconti.c @@ -0,0 +1,204 @@ +// 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/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 irq_chip irq_chip; +}; + +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 int visconti_gpio_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct visconti_gpio *priv; + struct irq_chip *irq_chip; + 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->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; + } + + irq_chip = &priv->irq_chip; + irq_chip->name = dev_name(dev); + irq_chip->irq_mask = irq_chip_mask_parent; + irq_chip->irq_unmask = irq_chip_unmask_parent; + irq_chip->irq_eoi = irq_chip_eoi_parent; + irq_chip->irq_set_type = visconti_gpio_irq_set_type; + irq_chip->flags = IRQCHIP_SET_TYPE_MASKED | IRQCHIP_MASK_ON_SUSPEND; + + girq = &priv->gpio_chip.irq; + girq->chip = 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 = of_match_ptr(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"); |