121 lines
2.3 KiB
C
121 lines
2.3 KiB
C
/*
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* Simulate an I2C port
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*
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* Copyright (c) 2014 Google, Inc
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*
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* SPDX-License-Identifier: GPL-2.0+
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*/
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#include <common.h>
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#include <dm.h>
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#include <errno.h>
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#include <i2c.h>
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#include <asm/test.h>
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#include <dm/lists.h>
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#include <dm/device-internal.h>
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DECLARE_GLOBAL_DATA_PTR;
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struct sandbox_i2c_priv {
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bool test_mode;
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};
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static int get_emul(struct udevice *dev, struct udevice **devp,
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struct dm_i2c_ops **opsp)
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{
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struct dm_i2c_chip *plat;
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struct udevice *child;
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int ret;
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*devp = NULL;
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*opsp = NULL;
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plat = dev_get_parent_platdata(dev);
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if (!plat->emul) {
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ret = dm_scan_fdt_dev(dev);
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if (ret)
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return ret;
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for (device_find_first_child(dev, &child); child;
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device_find_next_child(&child)) {
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if (device_get_uclass_id(child) != UCLASS_I2C_EMUL)
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continue;
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ret = device_probe(child);
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if (ret)
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return ret;
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break;
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}
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if (child)
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plat->emul = child;
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else
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return -ENODEV;
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}
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*devp = plat->emul;
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*opsp = i2c_get_ops(plat->emul);
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return 0;
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}
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void sandbox_i2c_set_test_mode(struct udevice *bus, bool test_mode)
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{
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struct sandbox_i2c_priv *priv = dev_get_priv(bus);
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priv->test_mode = test_mode;
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}
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static int sandbox_i2c_xfer(struct udevice *bus, struct i2c_msg *msg,
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int nmsgs)
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{
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struct dm_i2c_bus *i2c = dev_get_uclass_priv(bus);
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struct sandbox_i2c_priv *priv = dev_get_priv(bus);
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struct dm_i2c_ops *ops;
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struct udevice *emul, *dev;
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bool is_read;
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int ret;
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/* Special test code to return success but with no emulation */
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if (priv->test_mode && msg->addr == SANDBOX_I2C_TEST_ADDR)
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return 0;
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ret = i2c_get_chip(bus, msg->addr, 1, &dev);
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if (ret)
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return ret;
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ret = get_emul(dev, &emul, &ops);
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if (ret)
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return ret;
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if (priv->test_mode) {
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/*
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* For testing, don't allow writing above 100KHz for writes and
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* 400KHz for reads.
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*/
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is_read = nmsgs > 1;
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if (i2c->speed_hz > (is_read ? 400000 : 100000)) {
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debug("%s: Max speed exceeded\n", __func__);
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return -EINVAL;
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}
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}
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return ops->xfer(emul, msg, nmsgs);
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}
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static const struct dm_i2c_ops sandbox_i2c_ops = {
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.xfer = sandbox_i2c_xfer,
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};
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static const struct udevice_id sandbox_i2c_ids[] = {
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{ .compatible = "sandbox,i2c" },
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{ }
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};
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U_BOOT_DRIVER(i2c_sandbox) = {
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.name = "i2c_sandbox",
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.id = UCLASS_I2C,
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.of_match = sandbox_i2c_ids,
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.ops = &sandbox_i2c_ops,
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.priv_auto_alloc_size = sizeof(struct sandbox_i2c_priv),
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};
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