linux-kernel - [PATCH] regcache: Demote defaults readback from HW to debug print

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Message-ID: <20260121234309.178391-1-marek.vasut+renesas@mailbox.org>
Date: Thu, 22 Jan 2026 00:42:58 +0100
From: Marek Vasut <marek.vasut+renesas@...lbox.org>
To: linux-kernel@...r.kernel.org
Cc: Marek Vasut <marek.vasut+renesas@...lbox.org>,
	Geert Uytterhoeven <geert@...ux-m68k.org>,
	"Rafael J. Wysocki" <rafael@...nel.org>,
	Danilo Krummrich <dakr@...nel.org>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Mark Brown <broonie@...nel.org>,
	linux-renesas-soc@...r.kernel.org
Subject: [PATCH] regcache: Demote defaults readback from HW to debug print

Since commit 632e04739c8f ("clk: rs9: Fix suspend/resume"), the
clk-renesas-pcie-9series driver produces the following print in
kernel log on boot:
"
clk-renesas-pcie-9series 8-0068: No cache defaults, reading back from HW
"
This is caused by the presence of .num_reg_defaults_raw in its struct
regmap_config, without a matching .reg_defaults_raw table of built-in
register default values.

This configuration is valid, and causes the regcache code to read the
default register settings from the hardware, which is a valid behavior
for this particular chip. In fact, this configuration is more common
than configuration with .reg_defaults_raw built-in register defaults.

Do not warn about the read of default values being read from hardware,
as that is too strong and seems unnecessary, turn the warning into a
debug print.

Suggested-by: Geert Uytterhoeven <geert@...ux-m68k.org>
Signed-off-by: Marek Vasut <marek.vasut+renesas@...lbox.org>
---
Cc: "Rafael J. Wysocki" <rafael@...nel.org>
Cc: Danilo Krummrich <dakr@...nel.org>
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc: Mark Brown <broonie@...nel.org>
Cc: linux-kernel@...r.kernel.org
Cc: linux-renesas-soc@...r.kernel.org
---
 drivers/base/regmap/regcache.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c
index 319c342bf5a06..a4e8983a5c6f7 100644
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -73,7 +73,7 @@ static int regcache_hw_init(struct regmap *map)

 	if (!map->reg_defaults_raw) {
 		bool cache_bypass = map->cache_bypass;
-		dev_warn(map->dev, "No cache defaults, reading back from HW\n");
+		dev_dbg(map->dev, "No cache defaults, reading back from HW\n");

 		/* Bypass the cache access till data read from HW */
 		map->cache_bypass = true;
-- 
2.51.0