mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Christian Marangi <ansuelsmth@gmail.com>
To: Michael Turquette <mturquette@baylibre.com>,
	Stephen Boyd <sboyd@kernel.org>,
	linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org,
	Robert Marko <robimarko@gmail.com>
Cc: Christian Marangi <ansuelsmth@gmail.com>
Subject: [PATCH] clk: Warn and add workaround on misuse of .parent_data with .name only
Date: Tue,  8 Nov 2022 21:49:18 +0100	[thread overview]
Message-ID: <20221108204918.2805-1-ansuelsmth@gmail.com> (raw)

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,
-- 
2.37.2


             reply	other threads:[~2022-11-08 20:49 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-11-08 20:49 Christian Marangi [this message]
2022-11-25 23:06 ` Christian Marangi

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20221108204918.2805-1-ansuelsmth@gmail.com \
    --to=ansuelsmth@gmail.com \
    --cc=linux-clk@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mturquette@baylibre.com \
    --cc=robimarko@gmail.com \
    --cc=sboyd@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

Powered by JetHome