1// SPDX-License-Identifier: GPL-2.0+ 2/* 3 * Simulate an I2C port 4 * 5 * Copyright (c) 2014 Google, Inc 6 */ 7 8#include <common.h> 9#include <dm.h> 10#include <errno.h> 11#include <i2c.h> 12#include <log.h> 13#include <asm/i2c.h> 14#include <asm/test.h> 15#include <dm/acpi.h> 16#include <dm/lists.h> 17#include <dm/device-internal.h> 18 19static int get_emul(struct udevice *dev, struct udevice **devp, 20 struct dm_i2c_ops **opsp) 21{ 22 struct dm_i2c_chip *plat; 23 int ret; 24 25 *devp = NULL; 26 *opsp = NULL; 27 plat = dev_get_parent_plat(dev); 28 if (!plat->emul) { 29 ret = i2c_emul_find(dev, &plat->emul); 30 if (ret) 31 return ret; 32 } 33 *devp = plat->emul; 34 *opsp = i2c_get_ops(plat->emul); 35 36 return 0; 37} 38 39void sandbox_i2c_set_test_mode(struct udevice *bus, bool test_mode) 40{ 41 struct sandbox_i2c_priv *priv = dev_get_priv(bus); 42 43 priv->test_mode = test_mode; 44} 45 46static int sandbox_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, 47 int nmsgs) 48{ 49 struct dm_i2c_bus *i2c = dev_get_uclass_priv(bus); 50 struct sandbox_i2c_priv *priv = dev_get_priv(bus); 51 struct dm_i2c_ops *ops; 52 struct udevice *emul, *dev; 53 bool is_read; 54 int ret; 55 56 /* Special test code to return success but with no emulation */ 57 if (priv->test_mode && msg->addr == SANDBOX_I2C_TEST_ADDR) 58 return 0; 59 60 ret = i2c_get_chip(bus, msg->addr, 1, &dev); 61 if (ret) 62 return ret; 63 64 ret = get_emul(dev, &emul, &ops); 65 if (ret) 66 return ret; 67 68 if (priv->test_mode) { 69 /* 70 * For testing, don't allow writing above 100KHz for writes and 71 * 400KHz for reads. 72 */ 73 is_read = nmsgs > 1; 74 if (i2c->speed_hz > (is_read ? I2C_SPEED_FAST_RATE : 75 I2C_SPEED_STANDARD_RATE)) { 76 debug("%s: Max speed exceeded\n", __func__); 77 return -EINVAL; 78 } 79 } 80 81 return ops->xfer(emul, msg, nmsgs); 82} 83 84static const struct dm_i2c_ops sandbox_i2c_ops = { 85 .xfer = sandbox_i2c_xfer, 86}; 87 88static const struct udevice_id sandbox_i2c_ids[] = { 89 { .compatible = "sandbox,i2c" }, 90 { } 91}; 92 93U_BOOT_DRIVER(sandbox_i2c) = { 94 .name = "sandbox_i2c", 95 .id = UCLASS_I2C, 96 .of_match = sandbox_i2c_ids, 97 .ops = &sandbox_i2c_ops, 98 .priv_auto = sizeof(struct sandbox_i2c_priv), 99}; 100