Unverified Commit a07bff40 authored by Mark Brown's avatar Mark Brown
Browse files

regmap: Add a test case for write only registers 



Validate that attempts to read from write only registers fail and don't
somehow trigger spurious hardware accesses.

Signed-off-by: default avatarMark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230613-regmap-kunit-read-write-v1-2-2db337c52827@kernel.org


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 18003306

drivers/base/regmap/regmap-kunit.c

+32 −0
Original line number Diff line number Diff line
@@ -231,6 +231,37 @@ static void write_readonly(struct kunit *test) 
	regmap_exit(map);

}



static void read_writeonly(struct kunit *test)

{

	struct regcache_types *t = (struct regcache_types *)test->param_value;

	struct regmap *map;

	struct regmap_config config;

	struct regmap_ram_data *data;

	unsigned int val;

	int i;



	config = test_regmap_config;

	config.cache_type = t->type;

	config.readable_reg = reg_5_false;



	map = gen_regmap(&config, &data);

	KUNIT_ASSERT_FALSE(test, IS_ERR(map));

	if (IS_ERR(map))

		return;



	for (i = 0; i < BLOCK_TEST_SIZE; i++)

		data->read[i] = false;



	/* Try to read all the registers, the writeonly one should fail */

	for (i = 0; i < BLOCK_TEST_SIZE; i++)

		KUNIT_EXPECT_EQ(test, i != 5, regmap_read(map, i, &val) == 0);



	/* Did we trigger a hardware access? */

	KUNIT_EXPECT_FALSE(test, data->read[5]);



	regmap_exit(map);

}



static void reg_defaults(struct kunit *test)

{

	struct regcache_types *t = (struct regcache_types *)test->param_value;
@@ -1078,6 +1109,7 @@ static struct kunit_case regmap_test_cases[] = { 
	KUNIT_CASE_PARAM(bulk_write, regcache_types_gen_params),

	KUNIT_CASE_PARAM(bulk_read, regcache_types_gen_params),

	KUNIT_CASE_PARAM(write_readonly, regcache_types_gen_params),

	KUNIT_CASE_PARAM(read_writeonly, regcache_types_gen_params),

	KUNIT_CASE_PARAM(reg_defaults, regcache_types_gen_params),

	KUNIT_CASE_PARAM(reg_defaults_read_dev, regcache_types_gen_params),

	KUNIT_CASE_PARAM(register_patch, regcache_types_gen_params),