LXR uboot/drivers/i2c/sandbox

   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 <asm/test.h>
  13#include <dm/lists.h>
  14#include <dm/device-internal.h>
  15
  16struct sandbox_i2c_priv {
  17        bool test_mode;
  18};
  19
  20static int get_emul(struct udevice *dev, struct udevice **devp,
  21                    struct dm_i2c_ops **opsp)
  22{
  23        struct dm_i2c_chip *plat;
  24        int ret;
  25
  26        *devp = NULL;
  27        *opsp = NULL;
  28        plat = dev_get_parent_platdata(dev);
  29        if (!plat->emul) {
  30                ret = i2c_emul_find(dev, &plat->emul);
  31                if (ret)
  32                        return ret;
  33        }
  34        *devp = plat->emul;
  35        *opsp = i2c_get_ops(plat->emul);
  36
  37        return 0;
  38}
  39
  40void sandbox_i2c_set_test_mode(struct udevice *bus, bool test_mode)
  41{
  42        struct sandbox_i2c_priv *priv = dev_get_priv(bus);
  43
  44        priv->test_mode = test_mode;
  45}
  46
  47static int sandbox_i2c_xfer(struct udevice *bus, struct i2c_msg *msg,
  48                            int nmsgs)
  49{
  50        struct dm_i2c_bus *i2c = dev_get_uclass_priv(bus);
  51        struct sandbox_i2c_priv *priv = dev_get_priv(bus);
  52        struct dm_i2c_ops *ops;
  53        struct udevice *emul, *dev;
  54        bool is_read;
  55        int ret;
  56
  57        /* Special test code to return success but with no emulation */
  58        if (priv->test_mode && msg->addr == SANDBOX_I2C_TEST_ADDR)
  59                return 0;
  60
  61        ret = i2c_get_chip(bus, msg->addr, 1, &dev);
  62        if (ret)
  63                return ret;
  64
  65        ret = get_emul(dev, &emul, &ops);
  66        if (ret)
  67                return ret;
  68
  69        if (priv->test_mode) {
  70                /*
  71                * For testing, don't allow writing above 100KHz for writes and
  72                * 400KHz for reads.
  73                */
  74                is_read = nmsgs > 1;
  75                if (i2c->speed_hz > (is_read ? 400000 : 100000)) {
  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(i2c_sandbox) = {
  94        .name   = "i2c_sandbox",
  95        .id     = UCLASS_I2C,
  96        .of_match = sandbox_i2c_ids,
  97        .ops    = &sandbox_i2c_ops,
  98        .priv_auto_alloc_size = sizeof(struct sandbox_i2c_priv),
  99};
 100