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/mod_devicetable.h> 14 #include <linux/module.h> 15 #include <linux/platform_device.h> 16 #include <linux/regmap.h> 17 18 /* GPIO flavor */ 19 #define GPIO_REG_DIR 0x00 20 #define GPIO_REG_OUT 0x01 21 #define GPIO_REG_IN 0x02 22 #define GPIO_REG_IE 0x03 23 #define GPIO_REG_IP 0x04 24 25 /* input-only flavor */ 26 #define GPI_REG_IN 0x00 27 28 /* output-only flavor */ 29 #define GPO_REG_OUT 0x00 30 31 enum sl28cpld_gpio_type { 32 SL28CPLD_GPIO = 1, 33 SL28CPLD_GPI, 34 SL28CPLD_GPO, 35 }; 36 37 static const struct regmap_irq sl28cpld_gpio_irqs[] = { 38 REGMAP_IRQ_REG_LINE(0, 8), 39 REGMAP_IRQ_REG_LINE(1, 8), 40 REGMAP_IRQ_REG_LINE(2, 8), 41 REGMAP_IRQ_REG_LINE(3, 8), 42 REGMAP_IRQ_REG_LINE(4, 8), 43 REGMAP_IRQ_REG_LINE(5, 8), 44 REGMAP_IRQ_REG_LINE(6, 8), 45 REGMAP_IRQ_REG_LINE(7, 8), 46 }; 47 48 static int sl28cpld_gpio_irq_init(struct platform_device *pdev, 49 unsigned int base, 50 struct gpio_regmap_config *config) 51 { 52 struct regmap_irq_chip_data *irq_data; 53 struct regmap_irq_chip *irq_chip; 54 struct device *dev = &pdev->dev; 55 int irq, ret; 56 57 if (!device_property_read_bool(dev, "interrupt-controller")) 58 return 0; 59 60 irq = platform_get_irq(pdev, 0); 61 if (irq < 0) 62 return irq; 63 64 irq_chip = devm_kzalloc(dev, sizeof(*irq_chip), GFP_KERNEL); 65 if (!irq_chip) 66 return -ENOMEM; 67 68 irq_chip->name = "sl28cpld-gpio-irq"; 69 irq_chip->irqs = sl28cpld_gpio_irqs; 70 irq_chip->num_irqs = ARRAY_SIZE(sl28cpld_gpio_irqs); 71 irq_chip->num_regs = 1; 72 irq_chip->status_base = base + GPIO_REG_IP; 73 irq_chip->unmask_base = base + GPIO_REG_IE; 74 irq_chip->ack_base = base + GPIO_REG_IP; 75 76 ret = devm_regmap_add_irq_chip_fwnode(dev, dev_fwnode(dev), 77 config->regmap, irq, 78 IRQF_SHARED | IRQF_ONESHOT, 79 0, irq_chip, &irq_data); 80 if (ret) 81 return ret; 82 83 config->irq_domain = regmap_irq_get_domain(irq_data); 84 85 return 0; 86 } 87 88 static int sl28cpld_gpio_probe(struct platform_device *pdev) 89 { 90 struct gpio_regmap_config config = {0}; 91 enum sl28cpld_gpio_type type; 92 struct regmap *regmap; 93 u32 base; 94 int ret; 95 96 if (!pdev->dev.parent) 97 return -ENODEV; 98 99 type = (uintptr_t)device_get_match_data(&pdev->dev); 100 if (!type) 101 return -ENODEV; 102 103 ret = device_property_read_u32(&pdev->dev, "reg", &base); 104 if (ret) 105 return -EINVAL; 106 107 regmap = dev_get_regmap(pdev->dev.parent, NULL); 108 if (!regmap) 109 return -ENODEV; 110 111 config.regmap = regmap; 112 config.parent = &pdev->dev; 113 config.ngpio = 8; 114 115 switch (type) { 116 case SL28CPLD_GPIO: 117 config.reg_dat_base = base + GPIO_REG_IN; 118 config.reg_set_base = base + GPIO_REG_OUT; 119 /* reg_dir_out_base might be zero */ 120 config.reg_dir_out_base = GPIO_REGMAP_ADDR(base + GPIO_REG_DIR); 121 122 /* This type supports interrupts */ 123 ret = sl28cpld_gpio_irq_init(pdev, base, &config); 124 if (ret) 125 return ret; 126 break; 127 case SL28CPLD_GPO: 128 config.reg_set_base = base + GPO_REG_OUT; 129 break; 130 case SL28CPLD_GPI: 131 config.reg_dat_base = base + GPI_REG_IN; 132 break; 133 default: 134 dev_err(&pdev->dev, "unknown type %d\n", type); 135 return -ENODEV; 136 } 137 138 return PTR_ERR_OR_ZERO(devm_gpio_regmap_register(&pdev->dev, &config)); 139 } 140 141 static const struct of_device_id sl28cpld_gpio_of_match[] = { 142 { .compatible = "kontron,sl28cpld-gpio", .data = (void *)SL28CPLD_GPIO }, 143 { .compatible = "kontron,sl28cpld-gpi", .data = (void *)SL28CPLD_GPI }, 144 { .compatible = "kontron,sl28cpld-gpo", .data = (void *)SL28CPLD_GPO }, 145 {} 146 }; 147 MODULE_DEVICE_TABLE(of, sl28cpld_gpio_of_match); 148 149 static struct platform_driver sl28cpld_gpio_driver = { 150 .probe = sl28cpld_gpio_probe, 151 .driver = { 152 .name = "sl28cpld-gpio", 153 .of_match_table = sl28cpld_gpio_of_match, 154 }, 155 }; 156 module_platform_driver(sl28cpld_gpio_driver); 157 158 MODULE_DESCRIPTION("sl28cpld GPIO Driver"); 159 MODULE_AUTHOR("Michael Walle <michael@walle.cc>"); 160 MODULE_LICENSE("GPL"); 161