[PATCH v2 4/5] hw/sensor/tmp105: OS (one-shot) bit in config register always returns 0

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

Per datasheet, "ONE-SHOT (OS)", the OS bit always returns 0 when reading
the configuration register.

Clear the ONE_SHOT bit in the WRITE path. Now than the READ path is
simpler, we can also simplify tmp105_alarm_update().

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sensor/tmp105.c | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/hw/sensor/tmp105.c b/hw/sensor/tmp105.c
index 6740200aea..f5101af919 100644
--- a/hw/sensor/tmp105.c
+++ b/hw/sensor/tmp105.c
@@ -42,12 +42,8 @@ static void tmp105_interrupt_update(TMP105State *s)
 
 static void tmp105_alarm_update(TMP105State *s, bool one_shot)
 {
-    if (FIELD_EX8(s->config, CONFIG, SHUTDOWN_MODE)) {
-        if (one_shot) {
-            s->config = FIELD_DP8(s->config, CONFIG, ONE_SHOT, 0);
-        } else {
-            return;
-        }
+    if (FIELD_EX8(s->config, CONFIG, SHUTDOWN_MODE) && !one_shot) {
+        return;
     }
 
     if (FIELD_EX8(s->config, CONFIG, THERMOSTAT_MODE)) {
@@ -166,7 +162,7 @@ static void tmp105_write(TMP105State *s)
         if (FIELD_EX8(s->buf[0] & ~s->config, CONFIG, SHUTDOWN_MODE)) {
             printf("%s: TMP105 shutdown\n", __func__);
         }
-        s->config = s->buf[0];
+        s->config = FIELD_DP8(s->buf[0], CONFIG, ONE_SHOT, 0);
         s->faults = tmp105_faultq[FIELD_EX8(s->config, CONFIG, FAULT_QUEUE)];
         tmp105_alarm_update(s, FIELD_EX8(s->buf[0], CONFIG, ONE_SHOT));
         break;
-- 
2.45.2