1 /* 2 * Simulate an I2C eeprom 3 * 4 * Copyright (c) 2014 Google, Inc 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 */ 8 9 #include <common.h> 10 #include <dm.h> 11 #include <errno.h> 12 #include <i2c.h> 13 #include <malloc.h> 14 #include <asm/test.h> 15 16 #ifdef DEBUG 17 #define debug_buffer print_buffer 18 #else 19 #define debug_buffer(x, ...) 20 #endif 21 22 struct sandbox_i2c_flash_plat_data { 23 enum sandbox_i2c_eeprom_test_mode test_mode; 24 const char *filename; 25 int offset_len; /* Length of an offset in bytes */ 26 int size; /* Size of data buffer */ 27 }; 28 29 struct sandbox_i2c_flash { 30 uint8_t *data; 31 }; 32 33 void sandbox_i2c_eeprom_set_test_mode(struct udevice *dev, 34 enum sandbox_i2c_eeprom_test_mode mode) 35 { 36 struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(dev); 37 38 plat->test_mode = mode; 39 } 40 41 void sandbox_i2c_eeprom_set_offset_len(struct udevice *dev, int offset_len) 42 { 43 struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(dev); 44 45 plat->offset_len = offset_len; 46 } 47 48 static int sandbox_i2c_eeprom_xfer(struct udevice *emul, struct i2c_msg *msg, 49 int nmsgs) 50 { 51 struct sandbox_i2c_flash *priv = dev_get_priv(emul); 52 uint offset = 0; 53 54 debug("\n%s\n", __func__); 55 debug_buffer(0, priv->data, 1, 16, 0); 56 for (; nmsgs > 0; nmsgs--, msg++) { 57 struct sandbox_i2c_flash_plat_data *plat = 58 dev_get_platdata(emul); 59 int len; 60 u8 *ptr; 61 62 if (!plat->size) 63 return -ENODEV; 64 if (msg->addr + msg->len > plat->size) { 65 debug("%s: Address %x, len %x is outside range 0..%x\n", 66 __func__, msg->addr, msg->len, plat->size); 67 return -EINVAL; 68 } 69 len = msg->len; 70 debug(" %s: msg->len=%d", 71 msg->flags & I2C_M_RD ? "read" : "write", 72 msg->len); 73 if (msg->flags & I2C_M_RD) { 74 if (plat->test_mode == SIE_TEST_MODE_SINGLE_BYTE) 75 len = 1; 76 debug(", offset %x, len %x: ", offset, len); 77 memcpy(msg->buf, priv->data + offset, len); 78 memset(msg->buf + len, '\xff', msg->len - len); 79 debug_buffer(0, msg->buf, 1, msg->len, 0); 80 } else if (len >= plat->offset_len) { 81 int i; 82 83 ptr = msg->buf; 84 for (i = 0; i < plat->offset_len; i++, len--) 85 offset = (offset << 8) | *ptr++; 86 debug(", set offset %x: ", offset); 87 debug_buffer(0, msg->buf, 1, msg->len, 0); 88 if (plat->test_mode == SIE_TEST_MODE_SINGLE_BYTE) 89 len = min(len, 1); 90 91 /* For testing, map offsets into our limited buffer */ 92 for (i = 24; i > 0; i -= 8) { 93 if (offset > (1 << i)) { 94 offset = (offset >> i) | 95 (offset & ((1 << i) - 1)); 96 offset += i; 97 } 98 } 99 memcpy(priv->data + offset, ptr, len); 100 } 101 } 102 debug_buffer(0, priv->data, 1, 16, 0); 103 104 return 0; 105 } 106 107 struct dm_i2c_ops sandbox_i2c_emul_ops = { 108 .xfer = sandbox_i2c_eeprom_xfer, 109 }; 110 111 static int sandbox_i2c_eeprom_ofdata_to_platdata(struct udevice *dev) 112 { 113 struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(dev); 114 115 plat->size = dev_read_u32_default(dev, "sandbox,size", 32); 116 plat->filename = dev_read_string(dev, "sandbox,filename"); 117 if (!plat->filename) { 118 debug("%s: No filename for device '%s'\n", __func__, 119 dev->name); 120 return -EINVAL; 121 } 122 plat->test_mode = SIE_TEST_MODE_NONE; 123 plat->offset_len = 1; 124 125 return 0; 126 } 127 128 static int sandbox_i2c_eeprom_probe(struct udevice *dev) 129 { 130 struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(dev); 131 struct sandbox_i2c_flash *priv = dev_get_priv(dev); 132 133 priv->data = calloc(1, plat->size); 134 if (!priv->data) 135 return -ENOMEM; 136 137 return 0; 138 } 139 140 static int sandbox_i2c_eeprom_remove(struct udevice *dev) 141 { 142 struct sandbox_i2c_flash *priv = dev_get_priv(dev); 143 144 free(priv->data); 145 146 return 0; 147 } 148 149 static const struct udevice_id sandbox_i2c_ids[] = { 150 { .compatible = "sandbox,i2c-eeprom" }, 151 { } 152 }; 153 154 U_BOOT_DRIVER(sandbox_i2c_emul) = { 155 .name = "sandbox_i2c_eeprom_emul", 156 .id = UCLASS_I2C_EMUL, 157 .of_match = sandbox_i2c_ids, 158 .ofdata_to_platdata = sandbox_i2c_eeprom_ofdata_to_platdata, 159 .probe = sandbox_i2c_eeprom_probe, 160 .remove = sandbox_i2c_eeprom_remove, 161 .priv_auto_alloc_size = sizeof(struct sandbox_i2c_flash), 162 .platdata_auto_alloc_size = sizeof(struct sandbox_i2c_flash_plat_data), 163 .ops = &sandbox_i2c_emul_ops, 164 }; 165