--- zzzz-none-000/linux-5.15.111/drivers/i2c/i2c-core-acpi.c	2023-05-11 14:00:40.000000000 +0000
+++ puma7-atom-6670-761/linux-5.15.111/drivers/i2c/i2c-core-acpi.c	2024-02-07 10:23:01.000000000 +0000
@@ -324,6 +324,13 @@
 	 * the speed of the bus to 400 KHz if a Silead device is present.
 	 */
 	{ "MSSL1680", 0 },
+	/*
+	 * For the FRITZ!Box 6690 we have a speed of 1 MHz defined in ACPI for
+	 * the PMIC, while the MPS PMIC only works with 400 KHz or 3.4 MHZ. As
+	 * all PMICs of our PUMA7 devices should have set a speed of 400KHz,
+	 * force this speed for all of them.
+	 */
+	{ "INT34D9", 0 },
 	{}
 };