[PATCH] regmap: Allow reads from write only registers with the flat cache

From: Mark Brown
Date: Sat Jun 17 2023 - 16:11:21 EST


The flat cache is intended for devices that need the lowest overhead so
doesn't track any sparseness.

Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---


Signed-off-by: Mark Brown,,, <broonie@xxxxxxxxxx>
---
drivers/base/regmap/regmap-kunit.c | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/base/regmap/regmap-kunit.c b/drivers/base/regmap/regmap-kunit.c
index 6f444ac0ec49..24257aa9004d 100644
--- a/drivers/base/regmap/regmap-kunit.c
+++ b/drivers/base/regmap/regmap-kunit.c
@@ -252,9 +252,18 @@ static void read_writeonly(struct kunit *test)
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);
+ /*
+ * Try to read all the registers, the writeonly one should
+ * fail if we aren't using the flat cache.
+ */
+ for (i = 0; i < BLOCK_TEST_SIZE; i++) {
+ if (t->type != REGCACHE_FLAT) {
+ KUNIT_EXPECT_EQ(test, i != 5,
+ regmap_read(map, i, &val) == 0);
+ } else {
+ KUNIT_EXPECT_EQ(test, 0, regmap_read(map, i, &val));
+ }
+ }

/* Did we trigger a hardware access? */
KUNIT_EXPECT_FALSE(test, data->read[5]);

---
base-commit: 3e47b8877d6c0f60943b00f3112756ca3b572cd6
change-id: 20230617-regmap-kunit-read-writeonly-flat-d342e0948e82

Best regards,
--
Mark Brown,,, <broonie@xxxxxxxxxx>