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1// SPDX-License-Identifier: GPL-2.0-only2/* Abilis Systems MODULE DESCRIPTION3 *4 * Copyright (C) Abilis Systems 20135 *6 * Authors: Sascha Leuenberger <sascha.leuenberger@abilis.com>7 * Christian Ruppert <christian.ruppert@abilis.com>8 */9 10#include <linux/kernel.h>11#include <linux/module.h>12#include <linux/platform_device.h>13#include <linux/gpio/driver.h>14#include <linux/slab.h>15#include <linux/irq.h>16#include <linux/irqdomain.h>17#include <linux/interrupt.h>18#include <linux/io.h>19#include <linux/of.h>20#include <linux/of_platform.h>21#include <linux/spinlock.h>22#include <linux/bitops.h>23#include <linux/pinctrl/consumer.h>24 25#define TB10X_GPIO_DIR_IN (0x00000000)26#define TB10X_GPIO_DIR_OUT (0x00000001)27#define OFFSET_TO_REG_DDR (0x00)28#define OFFSET_TO_REG_DATA (0x04)29#define OFFSET_TO_REG_INT_EN (0x08)30#define OFFSET_TO_REG_CHANGE (0x0C)31#define OFFSET_TO_REG_WRMASK (0x10)32#define OFFSET_TO_REG_INT_TYPE (0x14)33 34 35/**36 * @base: register base address37 * @domain: IRQ domain of GPIO generated interrupts managed by this controller38 * @irq: Interrupt line of parent interrupt controller39 * @gc: gpio_chip structure associated to this GPIO controller40 */41struct tb10x_gpio {42 void __iomem *base;43 struct irq_domain *domain;44 int irq;45 struct gpio_chip gc;46};47 48static inline u32 tb10x_reg_read(struct tb10x_gpio *gpio, unsigned int offs)49{50 return ioread32(gpio->base + offs);51}52 53static inline void tb10x_reg_write(struct tb10x_gpio *gpio, unsigned int offs,54 u32 val)55{56 iowrite32(val, gpio->base + offs);57}58 59static inline void tb10x_set_bits(struct tb10x_gpio *gpio, unsigned int offs,60 u32 mask, u32 val)61{62 u32 r;63 unsigned long flags;64 65 raw_spin_lock_irqsave(&gpio->gc.bgpio_lock, flags);66 67 r = tb10x_reg_read(gpio, offs);68 r = (r & ~mask) | (val & mask);69 70 tb10x_reg_write(gpio, offs, r);71 72 raw_spin_unlock_irqrestore(&gpio->gc.bgpio_lock, flags);73}74 75static int tb10x_gpio_to_irq(struct gpio_chip *chip, unsigned offset)76{77 struct tb10x_gpio *tb10x_gpio = gpiochip_get_data(chip);78 79 return irq_create_mapping(tb10x_gpio->domain, offset);80}81 82static int tb10x_gpio_irq_set_type(struct irq_data *data, unsigned int type)83{84 if ((type & IRQF_TRIGGER_MASK) != IRQ_TYPE_EDGE_BOTH) {85 pr_err("Only (both) edge triggered interrupts supported.\n");86 return -EINVAL;87 }88 89 irqd_set_trigger_type(data, type);90 91 return IRQ_SET_MASK_OK;92}93 94static irqreturn_t tb10x_gpio_irq_cascade(int irq, void *data)95{96 struct tb10x_gpio *tb10x_gpio = data;97 u32 r = tb10x_reg_read(tb10x_gpio, OFFSET_TO_REG_CHANGE);98 u32 m = tb10x_reg_read(tb10x_gpio, OFFSET_TO_REG_INT_EN);99 const unsigned long bits = r & m;100 int i;101 102 for_each_set_bit(i, &bits, 32)103 generic_handle_domain_irq(tb10x_gpio->domain, i);104 105 return IRQ_HANDLED;106}107 108static int tb10x_gpio_probe(struct platform_device *pdev)109{110 struct tb10x_gpio *tb10x_gpio;111 struct device *dev = &pdev->dev;112 struct device_node *np = dev->of_node;113 int ret = -EBUSY;114 u32 ngpio;115 116 if (!np)117 return -EINVAL;118 119 if (of_property_read_u32(np, "abilis,ngpio", &ngpio))120 return -EINVAL;121 122 tb10x_gpio = devm_kzalloc(dev, sizeof(*tb10x_gpio), GFP_KERNEL);123 if (tb10x_gpio == NULL)124 return -ENOMEM;125 126 tb10x_gpio->base = devm_platform_ioremap_resource(pdev, 0);127 if (IS_ERR(tb10x_gpio->base))128 return PTR_ERR(tb10x_gpio->base);129 130 tb10x_gpio->gc.label =131 devm_kasprintf(dev, GFP_KERNEL, "%pOF", pdev->dev.of_node);132 if (!tb10x_gpio->gc.label)133 return -ENOMEM;134 135 /*136 * Initialize generic GPIO with one single register for reading and setting137 * the lines, no special set or clear registers and a data direction register138 * wher 1 means "output".139 */140 ret = bgpio_init(&tb10x_gpio->gc, dev, 4,141 tb10x_gpio->base + OFFSET_TO_REG_DATA,142 NULL,143 NULL,144 tb10x_gpio->base + OFFSET_TO_REG_DDR,145 NULL,146 0);147 if (ret) {148 dev_err(dev, "unable to init generic GPIO\n");149 return ret;150 }151 tb10x_gpio->gc.base = -1;152 tb10x_gpio->gc.parent = dev;153 tb10x_gpio->gc.owner = THIS_MODULE;154 /*155 * ngpio is set by bgpio_init() but we override it, this .request()156 * callback also overrides the one set up by generic GPIO.157 */158 tb10x_gpio->gc.ngpio = ngpio;159 tb10x_gpio->gc.request = gpiochip_generic_request;160 tb10x_gpio->gc.free = gpiochip_generic_free;161 162 ret = devm_gpiochip_add_data(dev, &tb10x_gpio->gc, tb10x_gpio);163 if (ret < 0) {164 dev_err(dev, "Could not add gpiochip.\n");165 return ret;166 }167 168 platform_set_drvdata(pdev, tb10x_gpio);169 170 if (of_property_read_bool(np, "interrupt-controller")) {171 struct irq_chip_generic *gc;172 173 ret = platform_get_irq(pdev, 0);174 if (ret < 0)175 return ret;176 177 tb10x_gpio->gc.to_irq = tb10x_gpio_to_irq;178 tb10x_gpio->irq = ret;179 180 ret = devm_request_irq(dev, ret, tb10x_gpio_irq_cascade,181 IRQF_TRIGGER_NONE | IRQF_SHARED,182 dev_name(dev), tb10x_gpio);183 if (ret != 0)184 return ret;185 186 tb10x_gpio->domain = irq_domain_add_linear(np,187 tb10x_gpio->gc.ngpio,188 &irq_generic_chip_ops, NULL);189 if (!tb10x_gpio->domain) {190 return -ENOMEM;191 }192 193 ret = irq_alloc_domain_generic_chips(tb10x_gpio->domain,194 tb10x_gpio->gc.ngpio, 1, tb10x_gpio->gc.label,195 handle_edge_irq, IRQ_NOREQUEST, IRQ_NOPROBE,196 IRQ_GC_INIT_MASK_CACHE);197 if (ret)198 goto err_remove_domain;199 200 gc = tb10x_gpio->domain->gc->gc[0];201 gc->reg_base = tb10x_gpio->base;202 gc->chip_types[0].type = IRQ_TYPE_EDGE_BOTH;203 gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit;204 gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;205 gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;206 gc->chip_types[0].chip.irq_set_type = tb10x_gpio_irq_set_type;207 gc->chip_types[0].regs.ack = OFFSET_TO_REG_CHANGE;208 gc->chip_types[0].regs.mask = OFFSET_TO_REG_INT_EN;209 }210 211 return 0;212 213err_remove_domain:214 irq_domain_remove(tb10x_gpio->domain);215 return ret;216}217 218static void tb10x_gpio_remove(struct platform_device *pdev)219{220 struct tb10x_gpio *tb10x_gpio = platform_get_drvdata(pdev);221 222 if (tb10x_gpio->gc.to_irq) {223 irq_remove_generic_chip(tb10x_gpio->domain->gc->gc[0],224 BIT(tb10x_gpio->gc.ngpio) - 1, 0, 0);225 kfree(tb10x_gpio->domain->gc);226 irq_domain_remove(tb10x_gpio->domain);227 }228}229 230static const struct of_device_id tb10x_gpio_dt_ids[] = {231 { .compatible = "abilis,tb10x-gpio" },232 { }233};234MODULE_DEVICE_TABLE(of, tb10x_gpio_dt_ids);235 236static struct platform_driver tb10x_gpio_driver = {237 .probe = tb10x_gpio_probe,238 .remove_new = tb10x_gpio_remove,239 .driver = {240 .name = "tb10x-gpio",241 .of_match_table = tb10x_gpio_dt_ids,242 }243};244 245module_platform_driver(tb10x_gpio_driver);246MODULE_LICENSE("GPL");247MODULE_DESCRIPTION("tb10x gpio.");248