[PATCH v2 1/2] clk: Warn and add workaround on misuse of .parent_data with .name only

Christian Marangi
2023-01-31T16:08:47Z

By a simple mistake in a .parent_names to .parent_data conversion it was
found that clk core assume fw_name is always provided with a parent_data
struct for each parent and never fallback to .name to get parent name even
if declared.

This is caused by clk_core_get that only checks for parent .fw_name and
doesn't handle .name.

While it's sane to request the dev to correctly do the conversion and
add both .fw_name and .name in a parent_data struct, it's not sane to
silently drop parents without a warning.

Fix this in 2 ways. Add a kernel warning when a wrong implementation is
used and copy .name in .fw_name in parent map populate function to
handle clk problems and malfunctions.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
drivers/clk/clk.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 57b83665e5c3..dccd4ea6f692 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -4015,10 +4015,21 @@ static int clk_core_populate_parent_map(struct clk_core *core,
ret = clk_cpy_name(&parent->name, parent_names[i],
true);
} else if (parent_data) {
+ const char *parent_name;
+
parent->hw = parent_data[i].hw;
parent->index = parent_data[i].index;
+ parent_name = parent_data[i].fw_name;
+
+ if (!parent_name && parent_data[i].name) {
+ WARN(1, "Empty .fw_name with .name in %s's .parent_data. Using .name for .fw_name declaration.\n",
+ core->name);
+ parent_name = parent_data[i].name;
+ }
+
ret = clk_cpy_name(&parent->fw_name,
- parent_data[i].fw_name, false);
+ parent_name, false);
+
if (!ret)
ret = clk_cpy_name(&parent->name,
parent_data[i].name,
--
2.38.1