// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2015-2018 Pengutronix, Uwe Kleine-König <kernel@pengutronix.de> */ #include <linux/module.h> #include <linux/siox.h> #include <linux/gpio/driver.h> #include <linux/of.h> struct gpio_siox_ddata { struct gpio_chip gchip; struct irq_chip ichip; struct mutex lock; u8 setdata[1]; u8 getdata[3]; raw_spinlock_t irqlock; u32 irq_enable; u32 irq_status; u32 irq_type[20]; }; /* * Note that this callback only sets the value that is clocked out in the next * cycle. */ static int gpio_siox_set_data(struct siox_device *sdevice, u8 status, u8 buf[]) { struct gpio_siox_ddata *ddata = dev_get_drvdata(&sdevice->dev); mutex_lock(&ddata->lock); buf[0] = ddata->setdata[0]; mutex_unlock(&ddata->lock); return 0; } static int gpio_siox_get_data(struct siox_device *sdevice, const u8 buf[]) { struct gpio_siox_ddata *ddata = dev_get_drvdata(&sdevice->dev); size_t offset; u32 trigger; mutex_lock(&ddata->lock); raw_spin_lock_irq(&ddata->irqlock); for (offset = 0; offset < 12; ++offset) { unsigned int bitpos = 11 - offset; unsigned int gpiolevel = buf[bitpos / 8] & (1 << bitpos % 8); unsigned int prev_level = ddata->getdata[bitpos / 8] & (1 << (bitpos % 8)); u32 irq_type = ddata->irq_type[offset]; if (gpiolevel) { if ((irq_type & IRQ_TYPE_LEVEL_HIGH) || ((irq_type & IRQ_TYPE_EDGE_RISING) && !prev_level)) ddata->irq_status |= 1 << offset; } else { if ((irq_type & IRQ_TYPE_LEVEL_LOW) || ((irq_type & IRQ_TYPE_EDGE_FALLING) && prev_level)) ddata->irq_status |= 1 << offset; } } trigger = ddata->irq_status & ddata->irq_enable; raw_spin_unlock_irq(&ddata->irqlock); ddata->getdata[0] = buf[0]; ddata->getdata[1] = buf[1]; ddata->getdata[2] = buf[2]; mutex_unlock(&ddata->lock); for (offset = 0; offset < 12; ++offset) { if (trigger & (1 << offset)) { struct irq_domain *irqdomain = ddata->gchip.irq.domain; unsigned int irq = irq_find_mapping(irqdomain, offset); /* * Conceptually handle_nested_irq should call the flow * handler of the irq chip. But it doesn't, so we have * to clean the irq_status here. */ raw_spin_lock_irq(&ddata->irqlock); ddata->irq_status &= ~(1 << offset); raw_spin_unlock_irq(&ddata->irqlock); handle_nested_irq(irq); } } return 0; } static void gpio_siox_irq_ack(struct irq_data *d) { struct irq_chip *ic = irq_data_get_irq_chip(d); struct gpio_siox_ddata *ddata = container_of(ic, struct gpio_siox_ddata, ichip); raw_spin_lock(&ddata->irqlock); ddata->irq_status &= ~(1 << d->hwirq); raw_spin_unlock(&ddata->irqlock); } static void gpio_siox_irq_mask(struct irq_data *d) { struct irq_chip *ic = irq_data_get_irq_chip(d); struct gpio_siox_ddata *ddata = container_of(ic, struct gpio_siox_ddata, ichip); raw_spin_lock(&ddata->irqlock); ddata->irq_enable &= ~(1 << d->hwirq); raw_spin_unlock(&ddata->irqlock); } static void gpio_siox_irq_unmask(struct irq_data *d) { struct irq_chip *ic = irq_data_get_irq_chip(d); struct gpio_siox_ddata *ddata = container_of(ic, struct gpio_siox_ddata, ichip); raw_spin_lock(&ddata->irqlock); ddata->irq_enable |= 1 << d->hwirq; raw_spin_unlock(&ddata->irqlock); } static int gpio_siox_irq_set_type(struct irq_data *d, u32 type) { struct irq_chip *ic = irq_data_get_irq_chip(d); struct gpio_siox_ddata *ddata = container_of(ic, struct gpio_siox_ddata, ichip); raw_spin_lock(&ddata->irqlock); ddata->irq_type[d->hwirq] = type; raw_spin_unlock(&ddata->irqlock); return 0; } static int gpio_siox_get(struct gpio_chip *chip, unsigned int offset) { struct gpio_siox_ddata *ddata = container_of(chip, struct gpio_siox_ddata, gchip); int ret; mutex_lock(&ddata->lock); if (offset >= 12) { unsigned int bitpos = 19 - offset; ret = ddata->setdata[0] & (1 << bitpos); } else { unsigned int bitpos = 11 - offset; ret = ddata->getdata[bitpos / 8] & (1 << (bitpos % 8)); } mutex_unlock(&ddata->lock); return ret; } static void gpio_siox_set(struct gpio_chip *chip, unsigned int offset, int value) { struct gpio_siox_ddata *ddata = container_of(chip, struct gpio_siox_ddata, gchip); u8 mask = 1 << (19 - offset); mutex_lock(&ddata->lock); if (value) ddata->setdata[0] |= mask; else ddata->setdata[0] &= ~mask; mutex_unlock(&ddata->lock); } static int gpio_siox_direction_input(struct gpio_chip *chip, unsigned int offset) { if (offset >= 12) return -EINVAL; return 0; } static int gpio_siox_direction_output(struct gpio_chip *chip, unsigned int offset, int value) { if (offset < 12) return -EINVAL; gpio_siox_set(chip, offset, value); return 0; } static int gpio_siox_get_direction(struct gpio_chip *chip, unsigned int offset) { if (offset < 12) return GPIO_LINE_DIRECTION_IN; else return GPIO_LINE_DIRECTION_OUT; } static int gpio_siox_probe(struct siox_device *sdevice) { struct gpio_siox_ddata *ddata; struct gpio_irq_chip *girq; struct device *dev = &sdevice->dev; int ret; ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL); if (!ddata) return -ENOMEM; dev_set_drvdata(dev, ddata); mutex_init(&ddata->lock); raw_spin_lock_init(&ddata->irqlock); ddata->gchip.base = -1; ddata->gchip.can_sleep = 1; ddata->gchip.parent = dev; ddata->gchip.owner = THIS_MODULE; ddata->gchip.get = gpio_siox_get; ddata->gchip.set = gpio_siox_set; ddata->gchip.direction_input = gpio_siox_direction_input; ddata->gchip.direction_output = gpio_siox_direction_output; ddata->gchip.get_direction = gpio_siox_get_direction; ddata->gchip.ngpio = 20; ddata->ichip.name = "siox-gpio"; ddata->ichip.irq_ack = gpio_siox_irq_ack; ddata->ichip.irq_mask = gpio_siox_irq_mask; ddata->ichip.irq_unmask = gpio_siox_irq_unmask; ddata->ichip.irq_set_type = gpio_siox_irq_set_type; girq = &ddata->gchip.irq; girq->chip = &ddata->ichip; girq->default_type = IRQ_TYPE_NONE; girq->handler = handle_level_irq; ret = devm_gpiochip_add_data(dev, &ddata->gchip, NULL); if (ret) dev_err(dev, "Failed to register gpio chip (%d)\n", ret); return ret; } static struct siox_driver gpio_siox_driver = { .probe = gpio_siox_probe, .set_data = gpio_siox_set_data, .get_data = gpio_siox_get_data, .driver = { .name = "gpio-siox", }, }; module_siox_driver(gpio_siox_driver); MODULE_AUTHOR("Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>"); MODULE_DESCRIPTION("SIOX gpio driver"); MODULE_LICENSE("GPL v2");