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 <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