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 14 struct bcm2835_gpios { 15 struct bcm2835_gpio_regs *reg; 16 }; 17 18 static int bcm2835_gpio_direction_input(struct udevice *dev, unsigned gpio) 19 { 20 struct bcm2835_gpios *gpios = dev_get_priv(dev); 21 unsigned val; 22 23 val = readl(&gpios->reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]); 24 val &= ~(BCM2835_GPIO_FSEL_MASK << BCM2835_GPIO_FSEL_SHIFT(gpio)); 25 val |= (BCM2835_GPIO_INPUT << BCM2835_GPIO_FSEL_SHIFT(gpio)); 26 writel(val, &gpios->reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]); 27 28 return 0; 29 } 30 31 static int bcm2835_gpio_direction_output(struct udevice *dev, unsigned gpio, 32 int value) 33 { 34 struct bcm2835_gpios *gpios = dev_get_priv(dev); 35 unsigned val; 36 37 gpio_set_value(gpio, value); 38 39 val = readl(&gpios->reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]); 40 val &= ~(BCM2835_GPIO_FSEL_MASK << BCM2835_GPIO_FSEL_SHIFT(gpio)); 41 val |= (BCM2835_GPIO_OUTPUT << BCM2835_GPIO_FSEL_SHIFT(gpio)); 42 writel(val, &gpios->reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]); 43 44 return 0; 45 } 46 47 static int bcm2835_get_value(const struct bcm2835_gpios *gpios, unsigned gpio) 48 { 49 unsigned val; 50 51 val = readl(&gpios->reg->gplev[BCM2835_GPIO_COMMON_BANK(gpio)]); 52 53 return (val >> BCM2835_GPIO_COMMON_SHIFT(gpio)) & 0x1; 54 } 55 56 static int bcm2835_gpio_get_value(struct udevice *dev, unsigned gpio) 57 { 58 const struct bcm2835_gpios *gpios = dev_get_priv(dev); 59 60 return bcm2835_get_value(gpios, gpio); 61 } 62 63 static int bcm2835_gpio_set_value(struct udevice *dev, unsigned gpio, 64 int value) 65 { 66 struct bcm2835_gpios *gpios = dev_get_priv(dev); 67 u32 *output_reg = value ? gpios->reg->gpset : gpios->reg->gpclr; 68 69 writel(1 << BCM2835_GPIO_COMMON_SHIFT(gpio), 70 &output_reg[BCM2835_GPIO_COMMON_BANK(gpio)]); 71 72 return 0; 73 } 74 75 int bcm2835_gpio_get_func_id(struct udevice *dev, unsigned gpio) 76 { 77 struct bcm2835_gpios *gpios = dev_get_priv(dev); 78 u32 val; 79 80 val = readl(&gpios->reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]); 81 82 return (val >> BCM2835_GPIO_FSEL_SHIFT(gpio) & BCM2835_GPIO_FSEL_MASK); 83 } 84 85 static int bcm2835_gpio_get_function(struct udevice *dev, unsigned offset) 86 { 87 int funcid = bcm2835_gpio_get_func_id(dev, offset); 88 89 switch (funcid) { 90 case BCM2835_GPIO_OUTPUT: 91 return GPIOF_OUTPUT; 92 case BCM2835_GPIO_INPUT: 93 return GPIOF_INPUT; 94 default: 95 return GPIOF_FUNC; 96 } 97 } 98 99 100 static const struct dm_gpio_ops gpio_bcm2835_ops = { 101 .direction_input = bcm2835_gpio_direction_input, 102 .direction_output = bcm2835_gpio_direction_output, 103 .get_value = bcm2835_gpio_get_value, 104 .set_value = bcm2835_gpio_set_value, 105 .get_function = bcm2835_gpio_get_function, 106 }; 107 108 static int bcm2835_gpio_probe(struct udevice *dev) 109 { 110 struct bcm2835_gpios *gpios = dev_get_priv(dev); 111 struct bcm2835_gpio_platdata *plat = dev_get_platdata(dev); 112 struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev); 113 114 uc_priv->bank_name = "GPIO"; 115 uc_priv->gpio_count = BCM2835_GPIO_COUNT; 116 gpios->reg = (struct bcm2835_gpio_regs *)plat->base; 117 118 return 0; 119 } 120 121 U_BOOT_DRIVER(gpio_bcm2835) = { 122 .name = "gpio_bcm2835", 123 .id = UCLASS_GPIO, 124 .ops = &gpio_bcm2835_ops, 125 .probe = bcm2835_gpio_probe, 126 .flags = DM_FLAG_PRE_RELOC, 127 .priv_auto_alloc_size = sizeof(struct bcm2835_gpios), 128 }; 129