GMINL-3234: Allow for a minimal sensor sampling rate

[android-x86/hardware-intel-libsensors.git] / description.c

diff --git a/description.c b/description.c
index ea2ece9..dbba158 100644 (file)
--- a/description.c
+++ b/description.c
@@ -212,7 +212,25 @@ float sensor_get_max_range (int s)
                }
 }
 
-float sensor_get_max_freq (int s)
+static float sensor_get_min_freq (int s)
+{
+       /*
+        * Check if a low cap has been specified for this sensor sampling rate.
+        * In some case, even when the driver supports lower rate, we still
+        * wish to receive a certain number of samples per seconds for various
+        * reasons (calibration, filtering, no change in power consumption...).
+        */
+
+       float min_freq;
+
+       if (!sensor_get_fl_prop(s, "min_freq", &min_freq))
+               return min_freq;
+
+       return 0;
+}
+
+
+static float sensor_get_max_freq (int s)
 {
        float max_freq;
 
@@ -428,6 +446,7 @@ max_delay_t sensor_get_max_delay (int s)
        char freqs_buf[100];
        char* cursor;
        float min_supported_rate = 1000;
+       float rate_cap;
        float sr;
 
        /* continuous, on-change: maximum sampling period allowed in microseconds.
@@ -465,6 +484,12 @@ max_delay_t sensor_get_max_delay (int s)
                }
        }
 
+       /* Check if a minimum rate was specified for this sensor */
+       rate_cap = sensor_get_min_freq(s);
+
+       if (min_supported_rate < rate_cap)
+               min_supported_rate = rate_cap;
+
        /* return 0 for wrong values */
        if (min_supported_rate < 0.1)
                return 0;