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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (C) 2015-2018 Pengutronix, Uwe Kleine-König <kernel@pengutronix.de>4 */5 6#include <linux/module.h>7#include <linux/siox.h>8#include <linux/gpio/driver.h>9#include <linux/of.h>10 11struct gpio_siox_ddata {12 struct gpio_chip gchip;13 struct mutex lock;14 u8 setdata[1];15 u8 getdata[3];16 17 raw_spinlock_t irqlock;18 u32 irq_enable;19 u32 irq_status;20 u32 irq_type[20];21};22 23/*24 * Note that this callback only sets the value that is clocked out in the next25 * cycle.26 */27static int gpio_siox_set_data(struct siox_device *sdevice, u8 status, u8 buf[])28{29 struct gpio_siox_ddata *ddata = dev_get_drvdata(&sdevice->dev);30 31 mutex_lock(&ddata->lock);32 buf[0] = ddata->setdata[0];33 mutex_unlock(&ddata->lock);34 35 return 0;36}37 38static int gpio_siox_get_data(struct siox_device *sdevice, const u8 buf[])39{40 struct gpio_siox_ddata *ddata = dev_get_drvdata(&sdevice->dev);41 size_t offset;42 u32 trigger;43 44 mutex_lock(&ddata->lock);45 46 raw_spin_lock_irq(&ddata->irqlock);47 48 for (offset = 0; offset < 12; ++offset) {49 unsigned int bitpos = 11 - offset;50 unsigned int gpiolevel = buf[bitpos / 8] & (1 << bitpos % 8);51 unsigned int prev_level =52 ddata->getdata[bitpos / 8] & (1 << (bitpos % 8));53 u32 irq_type = ddata->irq_type[offset];54 55 if (gpiolevel) {56 if ((irq_type & IRQ_TYPE_LEVEL_HIGH) ||57 ((irq_type & IRQ_TYPE_EDGE_RISING) && !prev_level))58 ddata->irq_status |= 1 << offset;59 } else {60 if ((irq_type & IRQ_TYPE_LEVEL_LOW) ||61 ((irq_type & IRQ_TYPE_EDGE_FALLING) && prev_level))62 ddata->irq_status |= 1 << offset;63 }64 }65 66 trigger = ddata->irq_status & ddata->irq_enable;67 68 raw_spin_unlock_irq(&ddata->irqlock);69 70 ddata->getdata[0] = buf[0];71 ddata->getdata[1] = buf[1];72 ddata->getdata[2] = buf[2];73 74 mutex_unlock(&ddata->lock);75 76 for (offset = 0; offset < 12; ++offset) {77 if (trigger & (1 << offset)) {78 struct irq_domain *irqdomain = ddata->gchip.irq.domain;79 unsigned int irq = irq_find_mapping(irqdomain, offset);80 81 /*82 * Conceptually handle_nested_irq should call the flow83 * handler of the irq chip. But it doesn't, so we have84 * to clean the irq_status here.85 */86 raw_spin_lock_irq(&ddata->irqlock);87 ddata->irq_status &= ~(1 << offset);88 raw_spin_unlock_irq(&ddata->irqlock);89 90 handle_nested_irq(irq);91 }92 }93 94 return 0;95}96 97static void gpio_siox_irq_ack(struct irq_data *d)98{99 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);100 struct gpio_siox_ddata *ddata = gpiochip_get_data(gc);101 102 raw_spin_lock(&ddata->irqlock);103 ddata->irq_status &= ~(1 << d->hwirq);104 raw_spin_unlock(&ddata->irqlock);105}106 107static void gpio_siox_irq_mask(struct irq_data *d)108{109 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);110 struct gpio_siox_ddata *ddata = gpiochip_get_data(gc);111 112 raw_spin_lock(&ddata->irqlock);113 ddata->irq_enable &= ~(1 << d->hwirq);114 raw_spin_unlock(&ddata->irqlock);115 gpiochip_disable_irq(gc, irqd_to_hwirq(d));116}117 118static void gpio_siox_irq_unmask(struct irq_data *d)119{120 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);121 struct gpio_siox_ddata *ddata = gpiochip_get_data(gc);122 123 gpiochip_enable_irq(gc, irqd_to_hwirq(d));124 raw_spin_lock(&ddata->irqlock);125 ddata->irq_enable |= 1 << d->hwirq;126 raw_spin_unlock(&ddata->irqlock);127}128 129static int gpio_siox_irq_set_type(struct irq_data *d, u32 type)130{131 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);132 struct gpio_siox_ddata *ddata = gpiochip_get_data(gc);133 134 raw_spin_lock(&ddata->irqlock);135 ddata->irq_type[d->hwirq] = type;136 raw_spin_unlock(&ddata->irqlock);137 138 return 0;139}140 141static int gpio_siox_get(struct gpio_chip *chip, unsigned int offset)142{143 struct gpio_siox_ddata *ddata = gpiochip_get_data(chip);144 int ret;145 146 mutex_lock(&ddata->lock);147 148 if (offset >= 12) {149 unsigned int bitpos = 19 - offset;150 151 ret = ddata->setdata[0] & (1 << bitpos);152 } else {153 unsigned int bitpos = 11 - offset;154 155 ret = ddata->getdata[bitpos / 8] & (1 << (bitpos % 8));156 }157 158 mutex_unlock(&ddata->lock);159 160 return ret;161}162 163static void gpio_siox_set(struct gpio_chip *chip,164 unsigned int offset, int value)165{166 struct gpio_siox_ddata *ddata = gpiochip_get_data(chip);167 u8 mask = 1 << (19 - offset);168 169 mutex_lock(&ddata->lock);170 171 if (value)172 ddata->setdata[0] |= mask;173 else174 ddata->setdata[0] &= ~mask;175 176 mutex_unlock(&ddata->lock);177}178 179static int gpio_siox_direction_input(struct gpio_chip *chip,180 unsigned int offset)181{182 if (offset >= 12)183 return -EINVAL;184 185 return 0;186}187 188static int gpio_siox_direction_output(struct gpio_chip *chip,189 unsigned int offset, int value)190{191 if (offset < 12)192 return -EINVAL;193 194 gpio_siox_set(chip, offset, value);195 return 0;196}197 198static int gpio_siox_get_direction(struct gpio_chip *chip, unsigned int offset)199{200 if (offset < 12)201 return GPIO_LINE_DIRECTION_IN;202 else203 return GPIO_LINE_DIRECTION_OUT;204}205 206static const struct irq_chip gpio_siox_irq_chip = {207 .name = "siox-gpio",208 .irq_ack = gpio_siox_irq_ack,209 .irq_mask = gpio_siox_irq_mask,210 .irq_unmask = gpio_siox_irq_unmask,211 .irq_set_type = gpio_siox_irq_set_type,212 .flags = IRQCHIP_IMMUTABLE,213 GPIOCHIP_IRQ_RESOURCE_HELPERS,214};215 216static int gpio_siox_probe(struct siox_device *sdevice)217{218 struct gpio_siox_ddata *ddata;219 struct gpio_irq_chip *girq;220 struct device *dev = &sdevice->dev;221 struct gpio_chip *gc;222 int ret;223 224 ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);225 if (!ddata)226 return -ENOMEM;227 228 dev_set_drvdata(dev, ddata);229 230 mutex_init(&ddata->lock);231 raw_spin_lock_init(&ddata->irqlock);232 233 gc = &ddata->gchip;234 gc->base = -1;235 gc->can_sleep = 1;236 gc->parent = dev;237 gc->owner = THIS_MODULE;238 gc->get = gpio_siox_get;239 gc->set = gpio_siox_set;240 gc->direction_input = gpio_siox_direction_input;241 gc->direction_output = gpio_siox_direction_output;242 gc->get_direction = gpio_siox_get_direction;243 gc->ngpio = 20;244 245 girq = &gc->irq;246 gpio_irq_chip_set_chip(girq, &gpio_siox_irq_chip);247 girq->default_type = IRQ_TYPE_NONE;248 girq->handler = handle_level_irq;249 girq->threaded = true;250 251 ret = devm_gpiochip_add_data(dev, gc, ddata);252 if (ret)253 dev_err(dev, "Failed to register gpio chip (%d)\n", ret);254 255 return ret;256}257 258static struct siox_driver gpio_siox_driver = {259 .probe = gpio_siox_probe,260 .set_data = gpio_siox_set_data,261 .get_data = gpio_siox_get_data,262 .driver = {263 .name = "gpio-siox",264 },265};266module_siox_driver(gpio_siox_driver);267 268MODULE_AUTHOR("Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>");269MODULE_DESCRIPTION("SIOX gpio driver");270MODULE_LICENSE("GPL v2");271