On 2023-03-10 at 18:04:10 +0100, Marco Pagani wrote:
> Add fake FPGA bridge driver with support functions. The driver includes
> a counter for the number of switching cycles. This module is part of
> the KUnit tests for the FPGA subsystem.
>
> Signed-off-by: Marco Pagani <marpagan@xxxxxxxxxx>
> ---
> drivers/fpga/tests/fake-fpga-bridge.c | 228 ++++++++++++++++++++++++++
> drivers/fpga/tests/fake-fpga-bridge.h | 36 ++++
> 2 files changed, 264 insertions(+)
> create mode 100644 drivers/fpga/tests/fake-fpga-bridge.c
> create mode 100644 drivers/fpga/tests/fake-fpga-bridge.h
>
> diff --git a/drivers/fpga/tests/fake-fpga-bridge.c b/drivers/fpga/tests/fake-fpga-bridge.c
> new file mode 100644
> index 000000000000..8a2f64fc1bbb
> --- /dev/null
> +++ b/drivers/fpga/tests/fake-fpga-bridge.c
> @@ -0,0 +1,228 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for the fake FPGA bridge
> + *
> + * Copyright (C) 2023 Red Hat, Inc.
> + *
> + * Author: Marco Pagani <marpagan@xxxxxxxxxx>
> + */
> +
> +#include <linux/types.h>
> +#include <linux/device.h>
> +#include <linux/platform_device.h>
> +#include <linux/fpga/fpga-bridge.h>
> +#include <kunit/test.h>
> +
> +#include "fake-fpga-bridge.h"
> +
> +#define FAKE_FPGA_BRIDGE_DEV_NAME "fake_fpga_bridge"
> +
> +struct fake_bridge_priv {
> + int id;
> + bool enable;
> + int cycles_count;
> + struct kunit *test;
> +};
> +
> +struct fake_bridge_data {
> + struct kunit *test;
> +};
> +
> +static int op_enable_show(struct fpga_bridge *bridge)
> +{
> + struct fake_bridge_priv *priv;
> +
> + priv = bridge->priv;
> +
> + if (priv->test)
> + kunit_info(priv->test, "Fake FPGA bridge %d: enable_show\n",
> + priv->id);
Why check the kunit pointer every time? I remember you mentioned that
the fake fpga modules are expected to be used out of Kunit test, so the
priv->test may be NULL? I suggest you work on these usecases in separate
patchsets. For now just check priv->test on probe is fine.
> +
> + return priv->enable;
> +}
> +
> +static int op_enable_set(struct fpga_bridge *bridge, bool enable)
> +{
> + struct fake_bridge_priv *priv;
> +
> + priv = bridge->priv;
> +
> + if (enable && !priv->enable)
> + priv->cycles_count++;
> +
> + priv->enable = enable;
> +
> + if (priv->test)
> + kunit_info(priv->test, "Fake FPGA bridge %d: enable_set: %d\n",
> + priv->id, enable);
> +
> + return 0;
> +}
> +
> +static void op_remove(struct fpga_bridge *bridge)
> +{
> + struct fake_bridge_priv *priv;
> +
> + priv = bridge->priv;
> +
> + if (priv->test)
> + kunit_info(priv->test, "Fake FPGA bridge: remove\n");
> +}
> +
> +static const struct fpga_bridge_ops fake_fpga_bridge_ops = {
> + .enable_show = op_enable_show,
> + .enable_set = op_enable_set,
> + .fpga_bridge_remove = op_remove,
> +};
> +
> +/**
> + * fake_fpga_bridge_register() - register a fake FPGA bridge.
> + * @bridge_ctx: fake FPGA bridge context data structure.
> + * @parent: parent device.
> + * @test: KUnit test context object.
> + *
> + * Return: 0 if registration succeeded, an error code otherwise.
> + */
> +int fake_fpga_bridge_register(struct fake_fpga_bridge *bridge_ctx,
> + struct device *parent, struct kunit *test)
struct fake_fpga_bridge *fake_fpga_bridge_register(struct device *parent, ...)
Is it better?
Thanks,
Yilun
> +{
> + struct fake_bridge_data pdata;
> + struct fake_bridge_priv *priv;
> + int ret;
> +
> + pdata.test = test;
> +
> + bridge_ctx->pdev = platform_device_alloc(FAKE_FPGA_BRIDGE_DEV_NAME,
> + PLATFORM_DEVID_AUTO);
> + if (IS_ERR(bridge_ctx->pdev)) {
> + pr_err("Fake FPGA bridge device allocation failed\n");
> + return -ENOMEM;
> + }
> +
> + bridge_ctx->pdev->dev.parent = parent;
> + platform_device_add_data(bridge_ctx->pdev, &pdata, sizeof(pdata));
> +
> + ret = platform_device_add(bridge_ctx->pdev);
> + if (ret) {
> + pr_err("Fake FPGA bridge device add failed\n");
> + platform_device_put(bridge_ctx->pdev);
> + return ret;
> + }
> +
> + bridge_ctx->bridge = platform_get_drvdata(bridge_ctx->pdev);
> +
> + if (test) {
> + priv = bridge_ctx->bridge->priv;
> + kunit_info(test, "Fake FPGA bridge %d registered\n", priv->id);
> + }
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_bridge_register);
> +
> +/**
> + * fake_fpga_bridge_unregister() - unregister a fake FPGA bridge.
> + * @bridge_ctx: fake FPGA bridge context data structure.
> + */
> +void fake_fpga_bridge_unregister(struct fake_fpga_bridge *bridge_ctx)
> +{
> + struct fake_bridge_priv *priv;
> + struct kunit *test;
> + int id;
> +
> + if (!bridge_ctx)
> + return;
> +
> + priv = bridge_ctx->bridge->priv;
> + test = priv->test;
> + id = priv->id;
> +
> + if (bridge_ctx->pdev) {
> + platform_device_unregister(bridge_ctx->pdev);
> + if (test)
> + kunit_info(test, "Fake FPGA bridge %d unregistered\n", id);
> + }
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_bridge_unregister);
> +
> +/**
> + * fake_fpga_bridge_get_state() - get state of a fake FPGA bridge.
> + * @bridge_ctx: fake FPGA bridge context data structure.
> + *
> + * Return: 1 if the bridge is enabled, 0 if disabled.
> + */
> +int fake_fpga_bridge_get_state(const struct fake_fpga_bridge *bridge_ctx)
> +{
> + return bridge_ctx->bridge->br_ops->enable_show(bridge_ctx->bridge);
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_bridge_get_state);
> +
> +/**
> + * fake_fpga_bridge_get_cycles_count() - get the number of switching cycles.
> + * @bridge_ctx: fake FPGA bridge context data structure.
> + *
> + * Return: number of switching cycles.
> + */
> +int fake_fpga_bridge_get_cycles_count(const struct fake_fpga_bridge *bridge_ctx)
> +{
> + struct fake_bridge_priv *priv;
> +
> + priv = bridge_ctx->bridge->priv;
> +
> + return priv->cycles_count;
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_bridge_get_cycles_count);
> +
> +static int fake_fpga_bridge_probe(struct platform_device *pdev)
> +{
> + struct device *dev;
> + struct fpga_bridge *bridge;
> + struct fake_bridge_data *pdata;
> + struct fake_bridge_priv *priv;
> + static int id_count;
> +
> + dev = &pdev->dev;
> + pdata = dev_get_platdata(dev);
> +
> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + priv->id = id_count++;
> + priv->enable = true;
> +
> + if (pdata)
> + priv->test = pdata->test;
> +
> + bridge = fpga_bridge_register(dev, "Fake FPGA Bridge",
> + &fake_fpga_bridge_ops, priv);
> + if (IS_ERR(bridge))
> + return PTR_ERR(bridge);
> +
> + platform_set_drvdata(pdev, bridge);
> +
> + return 0;
> +}
> +
> +static int fake_fpga_bridge_remove(struct platform_device *pdev)
> +{
> + struct fpga_bridge *bridge = platform_get_drvdata(pdev);
> +
> + fpga_bridge_unregister(bridge);
> +
> + return 0;
> +}
> +
> +static struct platform_driver fake_fpga_bridge_drv = {
> + .driver = {
> + .name = FAKE_FPGA_BRIDGE_DEV_NAME
> + },
> + .probe = fake_fpga_bridge_probe,
> + .remove = fake_fpga_bridge_remove,
> +};
> +
> +module_platform_driver(fake_fpga_bridge_drv);
> +
> +MODULE_AUTHOR("Marco Pagani <marpagan@xxxxxxxxxx>");
> +MODULE_DESCRIPTION("Fake FPGA Bridge");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/fpga/tests/fake-fpga-bridge.h b/drivers/fpga/tests/fake-fpga-bridge.h
> new file mode 100644
> index 000000000000..ae224b13f284
> --- /dev/null
> +++ b/drivers/fpga/tests/fake-fpga-bridge.h
> @@ -0,0 +1,36 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Header file for the fake FPGA bridge
> + *
> + * Copyright (C) 2023 Red Hat, Inc.
> + *
> + * Author: Marco Pagani <marpagan@xxxxxxxxxx>
> + */
> +
> +#ifndef __FPGA_FAKE_BRIDGE_H
> +#define __FPGA_FAKE_BRIDGE_H
> +
> +#include <linux/platform_device.h>
> +#include <kunit/test.h>
> +
> +/**
> + * struct fake_fpga_bridge - fake FPGA bridge context data structure
> + *
> + * @bridge: FPGA bridge.
> + * @pdev: platform device of the FPGA bridge.
> + */
> +struct fake_fpga_bridge {
> + struct fpga_bridge *bridge;
> + struct platform_device *pdev;
> +};
> +
> +int fake_fpga_bridge_register(struct fake_fpga_bridge *bridge_ctx,
> + struct device *parent, struct kunit *test);
> +
> +void fake_fpga_bridge_unregister(struct fake_fpga_bridge *bridge_ctx);
> +
> +int fake_fpga_bridge_get_state(const struct fake_fpga_bridge *bridge_ctx);
> +
> +int fake_fpga_bridge_get_cycles_count(const struct fake_fpga_bridge *bridge_ctx);
> +
> +#endif /* __FPGA_FAKE_BRIDGE_H */
> --
> 2.39.2
>
