linux-kernel - [PATCH v3 1/2] i2c: smbus: remove i801 assumptions from SPD probing

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Message-Id: <20240709-piix4-spd-v3-1-9d1daa204983@weissschuh.net>
Date: Tue, 09 Jul 2024 19:35:35 +0200
From: Thomas Weißschuh <linux@...ssschuh.net>
To: Andi Shyti <andi.shyti@...nel.org>, Jean Delvare <jdelvare@...e.com>
Cc: linux-i2c@...r.kernel.org, linux-kernel@...r.kernel.org, 
 Guenter Roeck <linux@...ck-us.net>, 
 Wolfram Sang <wsa+renesas@...g-engineering.com>, 
 Heiner Kallweit <hkallweit1@...il.com>, 
 Thomas Weißschuh <linux@...ssschuh.net>
Subject: [PATCH v3 1/2] i2c: smbus: remove i801 assumptions from SPD
 probing

The check and warning are very specific to the SPD usage of the i801
driver. That was fine as long as i801 was the only caller of
i2c_register_spd(). Now that piix4 will be added as another user of that
function, the check and warning are not accurate anymore.
Instead of introducing a more complicated calling protocol only to print
a warning, drop the warning.
Even in cases where not all slots can be probed,
then at least probe the 8 slots that can be.

Signed-off-by: Thomas Weißschuh <linux@...ssschuh.net>
---
 drivers/i2c/i2c-smbus.c | 15 ++++-----------
 1 file changed, 4 insertions(+), 11 deletions(-)

diff --git a/drivers/i2c/i2c-smbus.c b/drivers/i2c/i2c-smbus.c
index f809f0ef2004..f0ac35fd0c5a 100644
--- a/drivers/i2c/i2c-smbus.c
+++ b/drivers/i2c/i2c-smbus.c
@@ -352,18 +352,11 @@ void i2c_register_spd(struct i2c_adapter *adap)
 		return;
 
 	/*
-	 * If we're a child adapter on a muxed segment, then limit slots to 8,
-	 * as this is the max number of SPD EEPROMs that can be addressed per bus.
+	 * The max number of SPD EEPROMs that can be addressed per bus is 8.
+	 * If more slots are present either muxed or multiple busses are
+	 * necessary or the additional slots are ignored.
 	 */
-	if (i2c_parent_is_i2c_adapter(adap)) {
-		slot_count = 8;
-	} else {
-		if (slot_count > 8) {
-			dev_warn(&adap->dev,
-				 "More than 8 memory slots on a single bus, contact i801 maintainer to add missing mux config\n");
-			return;
-		}
-	}
+	slot_count = min(slot_count, 8);
 
 	/*
 	 * Memory types could be found at section 7.18.2 (Memory Device — Type), table 78

-- 
2.45.2