Michael Walle | c66c256 | 2022-02-25 18:10:24 +0530 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0+ |
| 2 | /* |
| 3 | * GPIO driver for the sl28cpld |
| 4 | * |
| 5 | * Copyright (c) 2021 Michael Walle <michael@walle.cc> |
| 6 | */ |
| 7 | |
| 8 | #include <common.h> |
| 9 | #include <dm.h> |
| 10 | #include <asm/gpio.h> |
| 11 | #include <sl28cpld.h> |
| 12 | |
| 13 | /* GPIO flavor */ |
| 14 | #define SL28CPLD_GPIO_DIR 0x00 |
| 15 | #define SL28CPLD_GPIO_OUT 0x01 |
| 16 | #define SL28CPLD_GPIO_IN 0x02 |
| 17 | |
| 18 | /* input-only flavor */ |
| 19 | #define SL28CPLD_GPI_IN 0x00 |
| 20 | |
| 21 | /* output-only flavor */ |
| 22 | #define SL28CPLD_GPO_OUT 0x00 |
| 23 | |
| 24 | enum { |
| 25 | SL28CPLD_GPIO, |
| 26 | SL28CPLD_GPI, |
| 27 | SL28CPLD_GPO, |
| 28 | }; |
| 29 | |
| 30 | static int sl28cpld_gpio_get_value(struct udevice *dev, unsigned int gpio) |
| 31 | { |
| 32 | ulong type = dev_get_driver_data(dev); |
| 33 | int val, reg; |
| 34 | |
| 35 | switch (type) { |
| 36 | case SL28CPLD_GPIO: |
| 37 | reg = SL28CPLD_GPIO_IN; |
| 38 | break; |
| 39 | case SL28CPLD_GPI: |
| 40 | reg = SL28CPLD_GPI_IN; |
| 41 | break; |
| 42 | case SL28CPLD_GPO: |
| 43 | /* we are output only, thus just return the output value */ |
| 44 | reg = SL28CPLD_GPO_OUT; |
| 45 | break; |
| 46 | default: |
| 47 | return -EINVAL; |
| 48 | } |
| 49 | |
| 50 | val = sl28cpld_read(dev, reg); |
| 51 | |
| 52 | return val < 0 ? val : !!(val & BIT(gpio)); |
| 53 | } |
| 54 | |
| 55 | static int sl28cpld_gpio_set_value(struct udevice *dev, unsigned int gpio, |
| 56 | int value) |
| 57 | { |
| 58 | ulong type = dev_get_driver_data(dev); |
| 59 | uint reg; |
| 60 | |
| 61 | switch (type) { |
| 62 | case SL28CPLD_GPIO: |
| 63 | reg = SL28CPLD_GPIO_OUT; |
| 64 | break; |
| 65 | case SL28CPLD_GPO: |
| 66 | reg = SL28CPLD_GPO_OUT; |
| 67 | break; |
| 68 | case SL28CPLD_GPI: |
| 69 | default: |
| 70 | return -EINVAL; |
| 71 | } |
| 72 | |
| 73 | if (value) |
| 74 | return sl28cpld_update(dev, reg, 0, BIT(gpio)); |
| 75 | else |
| 76 | return sl28cpld_update(dev, reg, BIT(gpio), 0); |
| 77 | } |
| 78 | |
| 79 | static int sl28cpld_gpio_direction_input(struct udevice *dev, unsigned int gpio) |
| 80 | { |
| 81 | ulong type = dev_get_driver_data(dev); |
| 82 | |
| 83 | switch (type) { |
| 84 | case SL28CPLD_GPI: |
| 85 | return 0; |
| 86 | case SL28CPLD_GPIO: |
| 87 | return sl28cpld_update(dev, SL28CPLD_GPIO_DIR, BIT(gpio), 0); |
| 88 | case SL28CPLD_GPO: |
| 89 | default: |
| 90 | return -EINVAL; |
| 91 | } |
| 92 | } |
| 93 | |
| 94 | static int sl28cpld_gpio_direction_output(struct udevice *dev, |
| 95 | unsigned int gpio, int value) |
| 96 | { |
| 97 | ulong type = dev_get_driver_data(dev); |
| 98 | int ret; |
| 99 | |
| 100 | /* set_value() will report an error if we are input-only */ |
| 101 | ret = sl28cpld_gpio_set_value(dev, gpio, value); |
| 102 | if (ret) |
| 103 | return ret; |
| 104 | |
| 105 | if (type == SL28CPLD_GPIO) |
| 106 | return sl28cpld_update(dev, SL28CPLD_GPIO_DIR, 0, BIT(gpio)); |
| 107 | |
| 108 | return 0; |
| 109 | } |
| 110 | |
| 111 | static int sl28cpld_gpio_get_function(struct udevice *dev, unsigned int gpio) |
| 112 | { |
| 113 | ulong type = dev_get_driver_data(dev); |
| 114 | int val; |
| 115 | |
| 116 | switch (type) { |
| 117 | case SL28CPLD_GPIO: |
| 118 | val = sl28cpld_read(dev, SL28CPLD_GPIO_DIR); |
| 119 | if (val < 0) |
| 120 | return val; |
| 121 | if (val & BIT(gpio)) |
| 122 | return GPIOF_OUTPUT; |
| 123 | else |
| 124 | return GPIOF_INPUT; |
| 125 | case SL28CPLD_GPI: |
| 126 | return GPIOF_INPUT; |
| 127 | case SL28CPLD_GPO: |
| 128 | return GPIOF_OUTPUT; |
| 129 | default: |
| 130 | return -EINVAL; |
| 131 | } |
| 132 | } |
| 133 | |
| 134 | static const struct dm_gpio_ops sl28cpld_gpio_ops = { |
| 135 | .direction_input = sl28cpld_gpio_direction_input, |
| 136 | .direction_output = sl28cpld_gpio_direction_output, |
| 137 | .get_value = sl28cpld_gpio_get_value, |
| 138 | .set_value = sl28cpld_gpio_set_value, |
| 139 | .get_function = sl28cpld_gpio_get_function, |
| 140 | }; |
| 141 | |
| 142 | static int sl28cpld_gpio_probe(struct udevice *dev) |
| 143 | { |
| 144 | struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev); |
| 145 | |
| 146 | uc_priv->gpio_count = 8; |
| 147 | uc_priv->bank_name = dev_read_name(dev); |
| 148 | |
| 149 | return 0; |
| 150 | } |
| 151 | |
| 152 | static const struct udevice_id sl28cpld_gpio_ids[] = { |
| 153 | { .compatible = "kontron,sl28cpld-gpio", .data = SL28CPLD_GPIO}, |
| 154 | { .compatible = "kontron,sl28cpld-gpo", .data = SL28CPLD_GPO}, |
| 155 | { .compatible = "kontron,sl28cpld-gpi", .data = SL28CPLD_GPI}, |
| 156 | { } |
| 157 | }; |
| 158 | |
| 159 | U_BOOT_DRIVER(sl28cpld_gpio) = { |
| 160 | .name = "sl28cpld_gpio", |
| 161 | .id = UCLASS_GPIO, |
| 162 | .of_match = sl28cpld_gpio_ids, |
| 163 | .probe = sl28cpld_gpio_probe, |
| 164 | .ops = &sl28cpld_gpio_ops, |
| 165 | }; |