Re: [PATCH RESEND v2] clk: tests: Add tests for clk lookup by name

[Stephen Boyd <sboyd@kernel.org>]

Quoting Chen-Yu Tsai (2026-02-25 00:34:11)
> Clk lookup (by name) recently gained some performance improvements at
> the expense of more complexity within the lookup code.
> 
> To make sure that this works as intended and doesn't break, add some
> basic tests for this part of the CCF.
> 
> A new "clk_hw_lookup()" function is added purely for running kunit
> tests.
> 
> Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
> 
> ---

Thanks. One nit below that I can likely fix before merging unless you
send again.

> diff --git a/drivers/clk/clk_test.c b/drivers/clk/clk_test.c
> index a268d7b5d4cb..a8989566946b 100644
> --- a/drivers/clk/clk_test.c
> +++ b/drivers/clk/clk_test.c
> @@ -175,6 +175,8 @@ static const struct clk_ops clk_multiple_parents_no_reparent_mux_ops = {
>         .set_parent = clk_multiple_parents_mux_set_parent,
>  };
>  
> +#define DUMMY_CLK_NAME "test_dummy_rate"
> +
>  static int clk_test_init_with_ops(struct kunit *test, const struct clk_ops *ops)
>  {
>         struct clk_dummy_context *ctx;
> @@ -187,7 +189,7 @@ static int clk_test_init_with_ops(struct kunit *test, const struct clk_ops *ops)
>         ctx->rate = DUMMY_CLOCK_INIT_RATE;
>         test->priv = ctx;
>  
> -       init.name = "test_dummy_rate";
> +       init.name = DUMMY_CLK_NAME;
>         init.ops = ops;
>         ctx->hw.init = &init;
>  
> @@ -3541,6 +3543,67 @@ static struct kunit_suite clk_hw_get_dev_of_node_test_suite = {
>         .test_cases = clk_hw_get_dev_of_node_test_cases,
>  };
>  
> +/*
> + * Test that clk lookup with a name that is not registered returns NULL.
> + */
> +static void clk_lookup_not_registered_clk_returns_NULL(struct kunit *test)
> +{
> +       KUNIT_EXPECT_PTR_EQ(test, NULL, clk_hw_lookup(DUMMY_CLK_NAME));
> +}
> +
> +/*
> + * Test that clk lookup with a name that is registered returns the clk.
> + */
> +static void clk_lookup_registered_clk_returns_clk(struct kunit *test)
> +{
> +       struct clk_hw *hw;
> +       struct clk_init_data init = {
> +               .name = DUMMY_CLK_NAME,
> +               .ops = &empty_clk_ops,
> +       };
> +
> +       hw = kunit_kzalloc(test, sizeof(*hw), GFP_KERNEL);
> +       KUNIT_ASSERT_NOT_ERR_OR_NULL(test, hw);
> +
> +       hw->init = &init;
> +       KUNIT_ASSERT_EQ(test, 0, clk_hw_register_kunit(test, NULL, hw));
> +
> +       KUNIT_EXPECT_PTR_EQ(test, hw, clk_hw_lookup(DUMMY_CLK_NAME));
> +}
> +
> +/*
> + * Test that clk lookup with a name that was unregistered returns NULL.
> + */
> +static void clk_lookup_unregistered_clk_returns_NULL(struct kunit *test)
> +{
> +       struct clk_hw *hw;
> +       struct clk_init_data init = {
> +               .name = DUMMY_CLK_NAME,
> +               .ops = &empty_clk_ops,
> +       };
> +
> +       hw = kunit_kzalloc(test, sizeof(*hw), GFP_KERNEL);
> +       KUNIT_ASSERT_NOT_ERR_OR_NULL(test, hw);
> +
> +       hw->init = &init;
> +       KUNIT_ASSERT_FALSE(test, clk_hw_register(NULL, hw));

Should be

	KUNIT_ASSERT_EQ(test, 0, clk_hw_register(NULL, hw))

because clk_hw_register() returns an int.

> +
> +       clk_hw_unregister(hw);
> +
> +       KUNIT_EXPECT_PTR_EQ(test, NULL, clk_hw_lookup(DUMMY_CLK_NAME));
> +}