[PULL,v2,48/61] hw/sensor/tmp105: Lower 4 bit of limit registers are always 0

Commit Message

Philippe Mathieu-Daudé Sept. 12, 2024, 6:52 a.m. UTC

From: Guenter Roeck <[e-mail]>

Per datasheet, "HIGH AND LOW LIMIT REGISTERS", the lower 4 bit
of the limit registers are unused and always report 0.
The lower 4 bit should not be used for temperature comparisons,
so mask the unused bits before storing the limits.

Signed-off-by: Guenter Roeck <[e-mail]>
Reviewed-by: Philippe Mathieu-Daudé <[e-mail]>
Reviewed-by: Cédric Le Goater <[e-mail]>
Message-Id: <[e-mail]>
Signed-off-by: Philippe Mathieu-Daudé <[e-mail]>
---
 hw/sensor/tmp105.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Patch

diff --git a/hw/sensor/tmp105.c b/hw/sensor/tmp105.c
index f5101af919..9d7b911f59 100644
--- a/hw/sensor/tmp105.c
+++ b/hw/sensor/tmp105.c
@@ -171,7 +171,7 @@  static void tmp105_write(TMP105State *s)
     case TMP105_REG_T_HIGH:
         if (s->len >= 3) {
             s->limit[s->pointer & 1] = (int16_t)
-                    ((((uint16_t) s->buf[0]) << 8) | s->buf[1]);
+                    ((((uint16_t) s->buf[0]) << 8) | (s->buf[1] & 0xf0));
         }
         tmp105_alarm_update(s, false);
         break;