// SPDX-License-Identifier: GPL-2.0-only /* * Emma Mobile GPIO Support - GIO * * Copyright (C) 2012 Magnus Damm */ #include <linux/init.h> #include <linux/platform_device.h> #include <linux/spinlock.h> #include <linux/interrupt.h> #include <linux/ioport.h> #include <linux/io.h> #include <linux/irq.h> #include <linux/irqdomain.h> #include <linux/bitops.h> #include <linux/err.h> #include <linux/gpio/driver.h> #include <linux/slab.h> #include <linux/module.h> #include <linux/pinctrl/consumer.h> struct em_gio_priv { void __iomem *base0; void __iomem *base1; spinlock_t sense_lock; struct platform_device *pdev; struct gpio_chip gpio_chip; struct irq_chip irq_chip; struct irq_domain *irq_domain; }; #define GIO_E1 0x00 #define GIO_E0 0x04 #define GIO_EM 0x04 #define GIO_OL 0x08 #define GIO_OH 0x0c #define GIO_I 0x10 #define GIO_IIA 0x14 #define GIO_IEN 0x18 #define GIO_IDS 0x1c #define GIO_IIM 0x1c #define GIO_RAW 0x20 #define GIO_MST 0x24 #define GIO_IIR 0x28 #define GIO_IDT0 0x40 #define GIO_IDT1 0x44 #define GIO_IDT2 0x48 #define GIO_IDT3 0x4c #define GIO_RAWBL 0x50 #define GIO_RAWBH 0x54 #define GIO_IRBL 0x58 #define GIO_IRBH 0x5c #define GIO_IDT(n) (GIO_IDT0 + ((n) * 4)) static inline unsigned long em_gio_read(struct em_gio_priv *p, int offs) { if (offs < GIO_IDT0) return ioread32(p->base0 + offs); else return ioread32(p->base1 + (offs - GIO_IDT0)); } static inline void em_gio_write(struct em_gio_priv *p, int offs, unsigned long value) { if (offs < GIO_IDT0) iowrite32(value, p->base0 + offs); else iowrite32(value, p->base1 + (offs - GIO_IDT0)); } static void em_gio_irq_disable(struct irq_data *d) { struct em_gio_priv *p = irq_data_get_irq_chip_data(d); em_gio_write(p, GIO_IDS, BIT(irqd_to_hwirq(d))); } static void em_gio_irq_enable(struct irq_data *d) { struct em_gio_priv *p = irq_data_get_irq_chip_data(d); em_gio_write(p, GIO_IEN, BIT(irqd_to_hwirq(d))); } static int em_gio_irq_reqres(struct irq_data *d) { struct em_gio_priv *p = irq_data_get_irq_chip_data(d); int ret; ret = gpiochip_lock_as_irq(&p->gpio_chip, irqd_to_hwirq(d)); if (ret) { dev_err(p->gpio_chip.parent, "unable to lock HW IRQ %lu for IRQ\n", irqd_to_hwirq(d)); return ret; } return 0; } static void em_gio_irq_relres(struct irq_data *d) { struct em_gio_priv *p = irq_data_get_irq_chip_data(d); gpiochip_unlock_as_irq(&p->gpio_chip, irqd_to_hwirq(d)); } #define GIO_ASYNC(x) (x + 8) static unsigned char em_gio_sense_table[IRQ_TYPE_SENSE_MASK + 1] = { [IRQ_TYPE_EDGE_RISING] = GIO_ASYNC(0x00), [IRQ_TYPE_EDGE_FALLING] = GIO_ASYNC(0x01), [IRQ_TYPE_LEVEL_HIGH] = GIO_ASYNC(0x02), [IRQ_TYPE_LEVEL_LOW] = GIO_ASYNC(0x03), [IRQ_TYPE_EDGE_BOTH] = GIO_ASYNC(0x04), }; static int em_gio_irq_set_type(struct irq_data *d, unsigned int type) { unsigned char value = em_gio_sense_table[type & IRQ_TYPE_SENSE_MASK]; struct em_gio_priv *p = irq_data_get_irq_chip_data(d); unsigned int reg, offset, shift; unsigned long flags; unsigned long tmp; if (!value) return -EINVAL; offset = irqd_to_hwirq(d); pr_debug("gio: sense irq = %d, mode = %d\n", offset, value); /* 8 x 4 bit fields in 4 IDT registers */ reg = GIO_IDT(offset >> 3); shift = (offset & 0x07) << 4; spin_lock_irqsave(&p->sense_lock, flags); /* disable the interrupt in IIA */ tmp = em_gio_read(p, GIO_IIA); tmp &= ~BIT(offset); em_gio_write(p, GIO_IIA, tmp); /* change the sense setting in IDT */ tmp = em_gio_read(p, reg); tmp &= ~(0xf << shift); tmp |= value << shift; em_gio_write(p, reg, tmp); /* clear pending interrupts */ em_gio_write(p, GIO_IIR, BIT(offset)); /* enable the interrupt in IIA */ tmp = em_gio_read(p, GIO_IIA); tmp |= BIT(offset); em_gio_write(p, GIO_IIA, tmp); spin_unlock_irqrestore(&p->sense_lock, flags); return 0; } static irqreturn_t em_gio_irq_handler(int irq, void *dev_id) { struct em_gio_priv *p = dev_id; unsigned long pending; unsigned int offset, irqs_handled = 0; while ((pending = em_gio_read(p, GIO_MST))) { offset = __ffs(pending); em_gio_write(p, GIO_IIR, BIT(offset)); generic_handle_irq(irq_find_mapping(p->irq_domain, offset)); irqs_handled++; } return irqs_handled ? IRQ_HANDLED : IRQ_NONE; } static inline struct em_gio_priv *gpio_to_priv(struct gpio_chip *chip) { return gpiochip_get_data(chip); } static int em_gio_direction_input(struct gpio_chip *chip, unsigned offset) { em_gio_write(gpio_to_priv(chip), GIO_E0, BIT(offset)); return 0; } static int em_gio_get(struct gpio_chip *chip, unsigned offset) { return !!(em_gio_read(gpio_to_priv(chip), GIO_I) & BIT(offset)); } static void __em_gio_set(struct gpio_chip *chip, unsigned int reg, unsigned shift, int value) { /* upper 16 bits contains mask and lower 16 actual value */ em_gio_write(gpio_to_priv(chip), reg, (BIT(shift + 16)) | (value << shift)); } static void em_gio_set(struct gpio_chip *chip, unsigned offset, int value) { /* output is split into two registers */ if (offset < 16) __em_gio_set(chip, GIO_OL, offset, value); else __em_gio_set(chip, GIO_OH, offset - 16, value); } static int em_gio_direction_output(struct gpio_chip *chip, unsigned offset, int value) { /* write GPIO value to output before selecting output mode of pin */ em_gio_set(chip, offset, value); em_gio_write(gpio_to_priv(chip), GIO_E1, BIT(offset)); return 0; } static int em_gio_to_irq(struct gpio_chip *chip, unsigned offset) { return irq_create_mapping(gpio_to_priv(chip)->irq_domain, offset); } static int em_gio_request(struct gpio_chip *chip, unsigned offset) { return pinctrl_gpio_request(chip->base + offset); } static void em_gio_free(struct gpio_chip *chip, unsigned offset) { pinctrl_gpio_free(chip->base + offset); /* Set the GPIO as an input to ensure that the next GPIO request won't * drive the GPIO pin as an output. */ em_gio_direction_input(chip, offset); } static int em_gio_irq_domain_map(struct irq_domain *h, unsigned int irq, irq_hw_number_t hwirq) { struct em_gio_priv *p = h->host_data; pr_debug("gio: map hw irq = %d, irq = %d\n", (int)hwirq, irq); irq_set_chip_data(irq, h->host_data); irq_set_chip_and_handler(irq, &p->irq_chip, handle_level_irq); return 0; } static const struct irq_domain_ops em_gio_irq_domain_ops = { .map = em_gio_irq_domain_map, .xlate = irq_domain_xlate_twocell, }; static void em_gio_irq_domain_remove(void *data) { struct irq_domain *domain = data; irq_domain_remove(domain); } static int em_gio_probe(struct platform_device *pdev) { struct em_gio_priv *p; struct gpio_chip *gpio_chip; struct irq_chip *irq_chip; struct device *dev = &pdev->dev; const char *name = dev_name(dev); unsigned int ngpios; int irq[2], ret; p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL); if (!p) return -ENOMEM; p->pdev = pdev; platform_set_drvdata(pdev, p); spin_lock_init(&p->sense_lock); irq[0] = platform_get_irq(pdev, 0); if (irq[0] < 0) return irq[0]; irq[1] = platform_get_irq(pdev, 1); if (irq[1] < 0) return irq[1]; p->base0 = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(p->base0)) return PTR_ERR(p->base0); p->base1 = devm_platform_ioremap_resource(pdev, 1); if (IS_ERR(p->base1)) return PTR_ERR(p->base1); if (of_property_read_u32(dev->of_node, "ngpios", &ngpios)) { dev_err(dev, "Missing ngpios OF property\n"); return -EINVAL; } gpio_chip = &p->gpio_chip; gpio_chip->of_node = dev->of_node; gpio_chip->direction_input = em_gio_direction_input; gpio_chip->get = em_gio_get; gpio_chip->direction_output = em_gio_direction_output; gpio_chip->set = em_gio_set; gpio_chip->to_irq = em_gio_to_irq; gpio_chip->request = em_gio_request; gpio_chip->free = em_gio_free; gpio_chip->label = name; gpio_chip->parent = dev; gpio_chip->owner = THIS_MODULE; gpio_chip->base = -1; gpio_chip->ngpio = ngpios; irq_chip = &p->irq_chip; irq_chip->name = "gpio-em"; irq_chip->irq_mask = em_gio_irq_disable; irq_chip->irq_unmask = em_gio_irq_enable; irq_chip->irq_set_type = em_gio_irq_set_type; irq_chip->irq_request_resources = em_gio_irq_reqres; irq_chip->irq_release_resources = em_gio_irq_relres; irq_chip->flags = IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND; p->irq_domain = irq_domain_add_simple(dev->of_node, ngpios, 0, &em_gio_irq_domain_ops, p); if (!p->irq_domain) { dev_err(dev, "cannot initialize irq domain\n"); return -ENXIO; } ret = devm_add_action_or_reset(dev, em_gio_irq_domain_remove, p->irq_domain); if (ret) return ret; if (devm_request_irq(dev, irq[0], em_gio_irq_handler, 0, name, p)) { dev_err(dev, "failed to request low IRQ\n"); return -ENOENT; } if (devm_request_irq(dev, irq[1], em_gio_irq_handler, 0, name, p)) { dev_err(dev, "failed to request high IRQ\n"); return -ENOENT; } ret = devm_gpiochip_add_data(dev, gpio_chip, p); if (ret) { dev_err(dev, "failed to add GPIO controller\n"); return ret; } return 0; } static const struct of_device_id em_gio_dt_ids[] = { { .compatible = "renesas,em-gio", }, {}, }; MODULE_DEVICE_TABLE(of, em_gio_dt_ids); static struct platform_driver em_gio_device_driver = { .probe = em_gio_probe, .driver = { .name = "em_gio", .of_match_table = em_gio_dt_ids, } }; static int __init em_gio_init(void) { return platform_driver_register(&em_gio_device_driver); } postcore_initcall(em_gio_init); static void __exit em_gio_exit(void) { platform_driver_unregister(&em_gio_device_driver); } module_exit(em_gio_exit); MODULE_AUTHOR("Magnus Damm"); MODULE_DESCRIPTION("Renesas Emma Mobile GIO Driver"); MODULE_LICENSE("GPL v2");