1 /* 2 * Copyright (c) 2014-2015, Linaro Ltd and Contributors. All rights reserved. 3 * Copyright (c) 2014-2015, Hisilicon Ltd and Contributors. All rights reserved. 4 * 5 * GPIO driver for PL061 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions are met: 9 * 10 * Redistributions of source code must retain the above copyright notice, this 11 * list of conditions and the following disclaimer. 12 * 13 * Redistributions in binary form must reproduce the above copyright notice, 14 * this list of conditions and the following disclaimer in the documentation 15 * and/or other materials provided with the distribution. 16 * 17 * Neither the name of ARM nor the names of its contributors may be used 18 * to endorse or promote products derived from this software without specific 19 * prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 22 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 25 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include <console.h> 35 #include <debug.h> 36 #include <errno.h> 37 #include <gpio.h> 38 #include <mmio.h> 39 40 #define MAX_GPIO_DEVICES 32 41 #define GPIOS_PER_DEV 8 42 #define GPIO_DIR 0x400 43 44 #define BIT(nr) (1UL << (nr)) 45 46 struct gpio_device_t { 47 unsigned int base[MAX_GPIO_DEVICES]; 48 unsigned int count; 49 }; 50 51 static struct gpio_device_t gpio_dev; 52 53 /* return 0 for failure */ 54 static unsigned int find_gc_base(unsigned int gpio) 55 { 56 int gc; 57 58 gc = gpio / GPIOS_PER_DEV; 59 if (gc >= gpio_dev.count) 60 return 0; 61 return gpio_dev.base[gc]; 62 } 63 64 int gpio_direction_input(unsigned int gpio) 65 { 66 unsigned int gc_base, offset, data; 67 68 gc_base = find_gc_base(gpio); 69 if (!gc_base) 70 return -EINVAL; 71 offset = gpio % GPIOS_PER_DEV; 72 73 data = mmio_read_8(gc_base + GPIO_DIR); 74 data &= ~(1 << offset); 75 mmio_write_8(gc_base + GPIO_DIR, data); 76 return 0; 77 } 78 79 int gpio_direction_output(unsigned int gpio) 80 { 81 unsigned int gc_base, offset, data; 82 83 gc_base = find_gc_base(gpio); 84 if (!gc_base) 85 return -EINVAL; 86 offset = gpio % 8; 87 88 data = mmio_read_8(gc_base + GPIO_DIR); 89 data |= 1 << offset; 90 mmio_write_8(gc_base + GPIO_DIR, data); 91 return 0; 92 } 93 94 int gpio_get_value(unsigned int gpio) 95 { 96 unsigned int gc_base, offset; 97 98 gc_base = find_gc_base(gpio); 99 if (!gc_base) 100 return -EINVAL; 101 offset = gpio % 8; 102 103 return !!mmio_read_8(gc_base + (BIT(offset + 2))); 104 } 105 106 int gpio_set_value(unsigned int gpio, unsigned int value) 107 { 108 unsigned int gc_base, offset; 109 110 gc_base = find_gc_base(gpio); 111 if (!gc_base) 112 return -EINVAL; 113 offset = gpio % 8; 114 mmio_write_8(gc_base + (BIT(offset + 2)), !!value << offset); 115 return 0; 116 } 117 118 int gpio_register_device(unsigned int base) 119 { 120 int i; 121 if (gpio_dev.count > MAX_GPIO_DEVICES) 122 return -EINVAL; 123 for (i = 0; i < gpio_dev.count; i++) { 124 if (gpio_dev.base[i] == base) { 125 WARN("%s: duplicated gpio base\n", __func__); 126 return -EINVAL; 127 } 128 } 129 gpio_dev.base[gpio_dev.count] = base; 130 gpio_dev.count++; 131 return 0; 132 } 133
