1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * sl28cpld GPIO driver 4 * 5 * Copyright 2020 Michael Walle <michael@walle.cc> 6 */ 7 8 #include <linux/device.h> 9 #include <linux/gpio/driver.h> 10 #include <linux/gpio/regmap.h> 11 #include <linux/interrupt.h> 12 #include <linux/kernel.h> 13 #include <linux/module.h> 14 #include <linux/platform_device.h> 15 #include <linux/regmap.h> 16 17 /* GPIO flavor */ 18 #define GPIO_REG_DIR 0x00 19 #define GPIO_REG_OUT 0x01 20 #define GPIO_REG_IN 0x02 21 #define GPIO_REG_IE 0x03 22 #define GPIO_REG_IP 0x04 23 24 /* input-only flavor */ 25 #define GPI_REG_IN 0x00 26 27 /* output-only flavor */ 28 #define GPO_REG_OUT 0x00 29 30 enum sl28cpld_gpio_type { 31 SL28CPLD_GPIO = 1, 32 SL28CPLD_GPI, 33 SL28CPLD_GPO, 34 }; 35 36 static const struct regmap_irq sl28cpld_gpio_irqs[] = { 37 REGMAP_IRQ_REG_LINE(0, 8), 38 REGMAP_IRQ_REG_LINE(1, 8), 39 REGMAP_IRQ_REG_LINE(2, 8), 40 REGMAP_IRQ_REG_LINE(3, 8), 41 REGMAP_IRQ_REG_LINE(4, 8), 42 REGMAP_IRQ_REG_LINE(5, 8), 43 REGMAP_IRQ_REG_LINE(6, 8), 44 REGMAP_IRQ_REG_LINE(7, 8), 45 }; 46 47 static int sl28cpld_gpio_irq_init(struct platform_device *pdev, 48 unsigned int base, 49 struct gpio_regmap_config *config) 50 { 51 struct regmap_irq_chip_data *irq_data; 52 struct regmap_irq_chip *irq_chip; 53 struct device *dev = &pdev->dev; 54 int irq, ret; 55 56 if (!device_property_read_bool(dev, "interrupt-controller")) 57 return 0; 58 59 irq = platform_get_irq(pdev, 0); 60 if (irq < 0) 61 return irq; 62 63 irq_chip = devm_kzalloc(dev, sizeof(*irq_chip), GFP_KERNEL); 64 if (!irq_chip) 65 return -ENOMEM; 66 67 irq_chip->name = "sl28cpld-gpio-irq"; 68 irq_chip->irqs = sl28cpld_gpio_irqs; 69 irq_chip->num_irqs = ARRAY_SIZE(sl28cpld_gpio_irqs); 70 irq_chip->num_regs = 1; 71 irq_chip->status_base = base + GPIO_REG_IP; 72 irq_chip->unmask_base = base + GPIO_REG_IE; 73 irq_chip->ack_base = base + GPIO_REG_IP; 74 75 ret = devm_regmap_add_irq_chip_fwnode(dev, dev_fwnode(dev), 76 config->regmap, irq, 77 IRQF_SHARED | IRQF_ONESHOT, 78 0, irq_chip, &irq_data); 79 if (ret) 80 return ret; 81 82 config->irq_domain = regmap_irq_get_domain(irq_data); 83 84 return 0; 85 } 86 87 static int sl28cpld_gpio_probe(struct platform_device *pdev) 88 { 89 struct gpio_regmap_config config = {0}; 90 enum sl28cpld_gpio_type type; 91 struct regmap *regmap; 92 u32 base; 93 int ret; 94 95 if (!pdev->dev.parent) 96 return -ENODEV; 97 98 type = (uintptr_t)device_get_match_data(&pdev->dev); 99 if (!type) 100 return -ENODEV; 101 102 ret = device_property_read_u32(&pdev->dev, "reg", &base); 103 if (ret) 104 return -EINVAL; 105 106 regmap = dev_get_regmap(pdev->dev.parent, NULL); 107 if (!regmap) 108 return -ENODEV; 109 110 config.regmap = regmap; 111 config.parent = &pdev->dev; 112 config.ngpio = 8; 113 114 switch (type) { 115 case SL28CPLD_GPIO: 116 config.reg_dat_base = base + GPIO_REG_IN; 117 config.reg_set_base = base + GPIO_REG_OUT; 118 /* reg_dir_out_base might be zero */ 119 config.reg_dir_out_base = GPIO_REGMAP_ADDR(base + GPIO_REG_DIR); 120 121 /* This type supports interrupts */ 122 ret = sl28cpld_gpio_irq_init(pdev, base, &config); 123 if (ret) 124 return ret; 125 break; 126 case SL28CPLD_GPO: 127 config.reg_set_base = base + GPO_REG_OUT; 128 break; 129 case SL28CPLD_GPI: 130 config.reg_dat_base = base + GPI_REG_IN; 131 break; 132 default: 133 dev_err(&pdev->dev, "unknown type %d\n", type); 134 return -ENODEV; 135 } 136 137 return PTR_ERR_OR_ZERO(devm_gpio_regmap_register(&pdev->dev, &config)); 138 } 139 140 static const struct of_device_id sl28cpld_gpio_of_match[] = { 141 { .compatible = "kontron,sl28cpld-gpio", .data = (void *)SL28CPLD_GPIO }, 142 { .compatible = "kontron,sl28cpld-gpi", .data = (void *)SL28CPLD_GPI }, 143 { .compatible = "kontron,sl28cpld-gpo", .data = (void *)SL28CPLD_GPO }, 144 {} 145 }; 146 MODULE_DEVICE_TABLE(of, sl28cpld_gpio_of_match); 147 148 static struct platform_driver sl28cpld_gpio_driver = { 149 .probe = sl28cpld_gpio_probe, 150 .driver = { 151 .name = "sl28cpld-gpio", 152 .of_match_table = sl28cpld_gpio_of_match, 153 }, 154 }; 155 module_platform_driver(sl28cpld_gpio_driver); 156 157 MODULE_DESCRIPTION("sl28cpld GPIO Driver"); 158 MODULE_AUTHOR("Michael Walle <michael@walle.cc>"); 159 MODULE_LICENSE("GPL"); 160