1 /* 2 * Copyright (C) 2012 Vikram Narayananan 3 * <vikram186@gmail.com> 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 #include <common.h> 9 #include <dm.h> 10 #include <errno.h> 11 #include <asm/gpio.h> 12 #include <asm/io.h> 13 #include <fdtdec.h> 14 15 struct bcm2835_gpios { 16 struct bcm2835_gpio_regs *reg; 17 }; 18 19 static int bcm2835_gpio_direction_input(struct udevice *dev, unsigned gpio) 20 { 21 struct bcm2835_gpios *gpios = dev_get_priv(dev); 22 unsigned val; 23 24 val = readl(&gpios->reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]); 25 val &= ~(BCM2835_GPIO_FSEL_MASK << BCM2835_GPIO_FSEL_SHIFT(gpio)); 26 val |= (BCM2835_GPIO_INPUT << BCM2835_GPIO_FSEL_SHIFT(gpio)); 27 writel(val, &gpios->reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]); 28 29 return 0; 30 } 31 32 static int bcm2835_gpio_direction_output(struct udevice *dev, unsigned gpio, 33 int value) 34 { 35 struct bcm2835_gpios *gpios = dev_get_priv(dev); 36 unsigned val; 37 38 gpio_set_value(gpio, value); 39 40 val = readl(&gpios->reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]); 41 val &= ~(BCM2835_GPIO_FSEL_MASK << BCM2835_GPIO_FSEL_SHIFT(gpio)); 42 val |= (BCM2835_GPIO_OUTPUT << BCM2835_GPIO_FSEL_SHIFT(gpio)); 43 writel(val, &gpios->reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]); 44 45 return 0; 46 } 47 48 static int bcm2835_get_value(const struct bcm2835_gpios *gpios, unsigned gpio) 49 { 50 unsigned val; 51 52 val = readl(&gpios->reg->gplev[BCM2835_GPIO_COMMON_BANK(gpio)]); 53 54 return (val >> BCM2835_GPIO_COMMON_SHIFT(gpio)) & 0x1; 55 } 56 57 static int bcm2835_gpio_get_value(struct udevice *dev, unsigned gpio) 58 { 59 const struct bcm2835_gpios *gpios = dev_get_priv(dev); 60 61 return bcm2835_get_value(gpios, gpio); 62 } 63 64 static int bcm2835_gpio_set_value(struct udevice *dev, unsigned gpio, 65 int value) 66 { 67 struct bcm2835_gpios *gpios = dev_get_priv(dev); 68 u32 *output_reg = value ? gpios->reg->gpset : gpios->reg->gpclr; 69 70 writel(1 << BCM2835_GPIO_COMMON_SHIFT(gpio), 71 &output_reg[BCM2835_GPIO_COMMON_BANK(gpio)]); 72 73 return 0; 74 } 75 76 int bcm2835_gpio_get_func_id(struct udevice *dev, unsigned gpio) 77 { 78 struct bcm2835_gpios *gpios = dev_get_priv(dev); 79 u32 val; 80 81 val = readl(&gpios->reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]); 82 83 return (val >> BCM2835_GPIO_FSEL_SHIFT(gpio) & BCM2835_GPIO_FSEL_MASK); 84 } 85 86 static int bcm2835_gpio_get_function(struct udevice *dev, unsigned offset) 87 { 88 int funcid = bcm2835_gpio_get_func_id(dev, offset); 89 90 switch (funcid) { 91 case BCM2835_GPIO_OUTPUT: 92 return GPIOF_OUTPUT; 93 case BCM2835_GPIO_INPUT: 94 return GPIOF_INPUT; 95 default: 96 return GPIOF_FUNC; 97 } 98 } 99 100 101 static const struct dm_gpio_ops gpio_bcm2835_ops = { 102 .direction_input = bcm2835_gpio_direction_input, 103 .direction_output = bcm2835_gpio_direction_output, 104 .get_value = bcm2835_gpio_get_value, 105 .set_value = bcm2835_gpio_set_value, 106 .get_function = bcm2835_gpio_get_function, 107 }; 108 109 static int bcm2835_gpio_probe(struct udevice *dev) 110 { 111 struct bcm2835_gpios *gpios = dev_get_priv(dev); 112 struct bcm2835_gpio_platdata *plat = dev_get_platdata(dev); 113 struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev); 114 115 uc_priv->bank_name = "GPIO"; 116 uc_priv->gpio_count = BCM2835_GPIO_COUNT; 117 gpios->reg = (struct bcm2835_gpio_regs *)plat->base; 118 119 return 0; 120 } 121 122 #if CONFIG_IS_ENABLED(OF_CONTROL) 123 static const struct udevice_id bcm2835_gpio_id[] = { 124 {.compatible = "brcm,bcm2835-gpio"}, 125 {} 126 }; 127 128 static int bcm2835_gpio_ofdata_to_platdata(struct udevice *dev) 129 { 130 struct bcm2835_gpio_platdata *plat = dev_get_platdata(dev); 131 fdt_addr_t addr; 132 133 addr = devfdt_get_addr(dev); 134 if (addr == FDT_ADDR_T_NONE) 135 return -EINVAL; 136 137 plat->base = addr; 138 return 0; 139 } 140 #endif 141 142 U_BOOT_DRIVER(gpio_bcm2835) = { 143 .name = "gpio_bcm2835", 144 .id = UCLASS_GPIO, 145 .of_match = of_match_ptr(bcm2835_gpio_id), 146 .ofdata_to_platdata = of_match_ptr(bcm2835_gpio_ofdata_to_platdata), 147 .platdata_auto_alloc_size = sizeof(struct bcm2835_gpio_platdata), 148 .ops = &gpio_bcm2835_ops, 149 .probe = bcm2835_gpio_probe, 150 .flags = DM_FLAG_PRE_RELOC, 151 .priv_auto_alloc_size = sizeof(struct bcm2835_gpios), 152 }; 153