From e1919889ef78144811d8520fa25776fa73feee66 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Tue, 17 Nov 2020 12:56:33 +0000 Subject: [PATCH] hw/misc/tmp105: reset the T_low and T_High registers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The TMP105 datasheet (https://www.ti.com/lit/gpn/tmp105) says that the power-up reset values for the T_low and T_high registers are 80 degrees C and 75 degrees C, which are 0x500 and 0x4B0 hex according to table 5. These values are then shifted right by four bits to give the register reset values, since both registers store the 12 bits of temperature data in bits [15..4] of a 16 bit register. We were resetting these registers to zero, which is problematic for Linux guests which enable the alert interrupt and then immediately take an unexpected overtemperature alert because the current temperature is above freezing... Signed-off-by: Peter Maydell Reviewed-by: Cédric Le Goater Message-id: 20201110150023.25533-2-peter.maydell@linaro.org --- hw/misc/tmp105.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/hw/misc/tmp105.c b/hw/misc/tmp105.c index b47120492a..0a4aad4854 100644 --- a/hw/misc/tmp105.c +++ b/hw/misc/tmp105.c @@ -225,6 +225,9 @@ static void tmp105_reset(I2CSlave *i2c) s->faults = tmp105_faultq[(s->config >> 3) & 3]; s->alarm = 0; + s->limit[0] = 0x4b00; /* T_LOW, 75 degrees C */ + s->limit[1] = 0x5000; /* T_HIGH, 80 degrees C */ + tmp105_interrupt_update(s); }