1 /* 2 * Copyright (C) 2016 Socionext Inc. 3 * Author: Masahiro Yamada <yamada.masahiro@socionext.com> 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 #include <common.h> 9 #include <dm.h> 10 #include <linux/bitops.h> 11 #include <linux/io.h> 12 #include <linux/sizes.h> 13 #include <linux/errno.h> 14 #include <asm/gpio.h> 15 16 #define UNIPHIER_GPIO_PORTS_PER_BANK 8 17 18 #define UNIPHIER_GPIO_REG_DATA 0 /* data */ 19 #define UNIPHIER_GPIO_REG_DIR 4 /* direction (1:in, 0:out) */ 20 21 struct uniphier_gpio_priv { 22 void __iomem *base; 23 char bank_name[16]; 24 }; 25 26 static void uniphier_gpio_offset_write(struct udevice *dev, unsigned offset, 27 unsigned reg, int value) 28 { 29 struct uniphier_gpio_priv *priv = dev_get_priv(dev); 30 u32 tmp; 31 32 tmp = readl(priv->base + reg); 33 if (value) 34 tmp |= BIT(offset); 35 else 36 tmp &= ~BIT(offset); 37 writel(tmp, priv->base + reg); 38 } 39 40 static int uniphier_gpio_offset_read(struct udevice *dev, unsigned offset, 41 unsigned reg) 42 { 43 struct uniphier_gpio_priv *priv = dev_get_priv(dev); 44 45 return !!(readl(priv->base + reg) & BIT(offset)); 46 } 47 48 static int uniphier_gpio_direction_input(struct udevice *dev, unsigned offset) 49 { 50 uniphier_gpio_offset_write(dev, offset, UNIPHIER_GPIO_REG_DIR, 1); 51 52 return 0; 53 } 54 55 static int uniphier_gpio_direction_output(struct udevice *dev, unsigned offset, 56 int value) 57 { 58 uniphier_gpio_offset_write(dev, offset, UNIPHIER_GPIO_REG_DATA, value); 59 uniphier_gpio_offset_write(dev, offset, UNIPHIER_GPIO_REG_DIR, 0); 60 61 return 0; 62 } 63 64 static int uniphier_gpio_get_value(struct udevice *dev, unsigned offset) 65 { 66 return uniphier_gpio_offset_read(dev, offset, UNIPHIER_GPIO_REG_DATA); 67 } 68 69 static int uniphier_gpio_set_value(struct udevice *dev, unsigned offset, 70 int value) 71 { 72 uniphier_gpio_offset_write(dev, offset, UNIPHIER_GPIO_REG_DATA, value); 73 74 return 0; 75 } 76 77 static int uniphier_gpio_get_function(struct udevice *dev, unsigned offset) 78 { 79 return uniphier_gpio_offset_read(dev, offset, UNIPHIER_GPIO_REG_DIR) ? 80 GPIOF_INPUT : GPIOF_OUTPUT; 81 } 82 83 static const struct dm_gpio_ops uniphier_gpio_ops = { 84 .direction_input = uniphier_gpio_direction_input, 85 .direction_output = uniphier_gpio_direction_output, 86 .get_value = uniphier_gpio_get_value, 87 .set_value = uniphier_gpio_set_value, 88 .get_function = uniphier_gpio_get_function, 89 }; 90 91 static int uniphier_gpio_probe(struct udevice *dev) 92 { 93 struct uniphier_gpio_priv *priv = dev_get_priv(dev); 94 struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev); 95 fdt_addr_t addr; 96 unsigned int tmp; 97 98 addr = devfdt_get_addr(dev); 99 if (addr == FDT_ADDR_T_NONE) 100 return -EINVAL; 101 102 priv->base = devm_ioremap(dev, addr, SZ_8); 103 if (!priv->base) 104 return -ENOMEM; 105 106 uc_priv->gpio_count = UNIPHIER_GPIO_PORTS_PER_BANK; 107 108 tmp = (addr & 0xfff); 109 110 /* Unfortunately, there is a register hole at offset 0x90-0x9f. */ 111 if (tmp > 0x90) 112 tmp -= 0x10; 113 114 snprintf(priv->bank_name, sizeof(priv->bank_name) - 1, 115 "port%d-", (tmp - 8) / 8); 116 117 uc_priv->bank_name = priv->bank_name; 118 119 return 0; 120 } 121 122 /* .data = the number of GPIO banks */ 123 static const struct udevice_id uniphier_gpio_match[] = { 124 { .compatible = "socionext,uniphier-gpio" }, 125 { /* sentinel */ } 126 }; 127 128 U_BOOT_DRIVER(uniphier_gpio) = { 129 .name = "uniphier_gpio", 130 .id = UCLASS_GPIO, 131 .of_match = uniphier_gpio_match, 132 .probe = uniphier_gpio_probe, 133 .priv_auto_alloc_size = sizeof(struct uniphier_gpio_priv), 134 .ops = &uniphier_gpio_ops, 135 }; 136