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 DECLARE_GLOBAL_DATA_PTR; 23 24 struct sandbox_i2c_flash_plat_data { 25 enum sandbox_i2c_eeprom_test_mode test_mode; 26 const char *filename; 27 int offset_len; /* Length of an offset in bytes */ 28 int size; /* Size of data buffer */ 29 }; 30 31 struct sandbox_i2c_flash { 32 uint8_t *data; 33 }; 34 35 void sandbox_i2c_eeprom_set_test_mode(struct udevice *dev, 36 enum sandbox_i2c_eeprom_test_mode mode) 37 { 38 struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(dev); 39 40 plat->test_mode = mode; 41 } 42 43 void sandbox_i2c_eeprom_set_offset_len(struct udevice *dev, int offset_len) 44 { 45 struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(dev); 46 47 plat->offset_len = offset_len; 48 } 49 50 static int sandbox_i2c_eeprom_xfer(struct udevice *emul, struct i2c_msg *msg, 51 int nmsgs) 52 { 53 struct sandbox_i2c_flash *priv = dev_get_priv(emul); 54 uint offset = 0; 55 56 debug("\n%s\n", __func__); 57 debug_buffer(0, priv->data, 1, 16, 0); 58 for (; nmsgs > 0; nmsgs--, msg++) { 59 struct sandbox_i2c_flash_plat_data *plat = 60 dev_get_platdata(emul); 61 int len; 62 u8 *ptr; 63 64 if (!plat->size) 65 return -ENODEV; 66 if (msg->addr + msg->len > plat->size) { 67 debug("%s: Address %x, len %x is outside range 0..%x\n", 68 __func__, msg->addr, msg->len, plat->size); 69 return -EINVAL; 70 } 71 len = msg->len; 72 debug(" %s: msg->len=%d", 73 msg->flags & I2C_M_RD ? "read" : "write", 74 msg->len); 75 if (msg->flags & I2C_M_RD) { 76 if (plat->test_mode == SIE_TEST_MODE_SINGLE_BYTE) 77 len = 1; 78 debug(", offset %x, len %x: ", offset, len); 79 memcpy(msg->buf, priv->data + offset, len); 80 memset(msg->buf + len, '\xff', msg->len - len); 81 debug_buffer(0, msg->buf, 1, msg->len, 0); 82 } else if (len >= plat->offset_len) { 83 int i; 84 85 ptr = msg->buf; 86 for (i = 0; i < plat->offset_len; i++, len--) 87 offset = (offset << 8) | *ptr++; 88 debug(", set offset %x: ", offset); 89 debug_buffer(0, msg->buf, 1, msg->len, 0); 90 if (plat->test_mode == SIE_TEST_MODE_SINGLE_BYTE) 91 len = min(len, 1); 92 93 /* For testing, map offsets into our limited buffer */ 94 for (i = 24; i > 0; i -= 8) { 95 if (offset > (1 << i)) { 96 offset = (offset >> i) | 97 (offset & ((1 << i) - 1)); 98 offset += i; 99 } 100 } 101 memcpy(priv->data + offset, ptr, len); 102 } 103 } 104 debug_buffer(0, priv->data, 1, 16, 0); 105 106 return 0; 107 } 108 109 struct dm_i2c_ops sandbox_i2c_emul_ops = { 110 .xfer = sandbox_i2c_eeprom_xfer, 111 }; 112 113 static int sandbox_i2c_eeprom_ofdata_to_platdata(struct udevice *dev) 114 { 115 struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(dev); 116 117 plat->size = dev_read_u32_default(dev, "sandbox,size", 32); 118 plat->filename = dev_read_string(dev, "sandbox,filename"); 119 if (!plat->filename) { 120 debug("%s: No filename for device '%s'\n", __func__, 121 dev->name); 122 return -EINVAL; 123 } 124 plat->test_mode = SIE_TEST_MODE_NONE; 125 plat->offset_len = 1; 126 127 return 0; 128 } 129 130 static int sandbox_i2c_eeprom_probe(struct udevice *dev) 131 { 132 struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(dev); 133 struct sandbox_i2c_flash *priv = dev_get_priv(dev); 134 135 priv->data = calloc(1, plat->size); 136 if (!priv->data) 137 return -ENOMEM; 138 139 return 0; 140 } 141 142 static int sandbox_i2c_eeprom_remove(struct udevice *dev) 143 { 144 struct sandbox_i2c_flash *priv = dev_get_priv(dev); 145 146 free(priv->data); 147 148 return 0; 149 } 150 151 static const struct udevice_id sandbox_i2c_ids[] = { 152 { .compatible = "sandbox,i2c-eeprom" }, 153 { } 154 }; 155 156 U_BOOT_DRIVER(sandbox_i2c_emul) = { 157 .name = "sandbox_i2c_eeprom_emul", 158 .id = UCLASS_I2C_EMUL, 159 .of_match = sandbox_i2c_ids, 160 .ofdata_to_platdata = sandbox_i2c_eeprom_ofdata_to_platdata, 161 .probe = sandbox_i2c_eeprom_probe, 162 .remove = sandbox_i2c_eeprom_remove, 163 .priv_auto_alloc_size = sizeof(struct sandbox_i2c_flash), 164 .platdata_auto_alloc_size = sizeof(struct sandbox_i2c_flash_plat_data), 165 .ops = &sandbox_i2c_emul_ops, 166 }; 167