Merge tag 'iio-fixes-for-4.4a' of ssh://ra.kernel.org/pub/scm/linux/kernel/git/jic23...

[mirror_ubuntu-zesty-kernel.git] / drivers / iio / adc / vf610_adc.c

diff --git a/drivers/iio/adc/vf610_adc.c b/drivers/iio/adc/vf610_adc.c
index 599cde3d03a117358f86defec5dcd10ac25b1ed7..b10f629cc44b5e8aa27b9bde4a5c39fbc3694a5e 100644 (file)
--- a/drivers/iio/adc/vf610_adc.c
+++ b/drivers/iio/adc/vf610_adc.c
@@ -106,6 +106,13 @@
 
 #define DEFAULT_SAMPLE_TIME            1000
 
+/* V at 25°C of 696 mV */
+#define VF610_VTEMP25_3V0              950
+/* V at 25°C of 699 mV */
+#define VF610_VTEMP25_3V3              867
+/* Typical sensor slope coefficient at all temperatures */
+#define VF610_TEMP_SLOPE_COEFF         1840
+
 enum clk_sel {
        VF610_ADCIOC_BUSCLK_SET,
        VF610_ADCIOC_ALTCLK_SET,
@@ -197,6 +204,8 @@ static inline void vf610_adc_calculate_rates(struct vf610_adc *info)
                adc_feature->clk_div = 8;
        }
 
+       adck_rate = ipg_rate / adc_feature->clk_div;
+
        /*
         * Determine the long sample time adder value to be used based
         * on the default minimum sample time provided.
@@ -221,7 +230,6 @@ static inline void vf610_adc_calculate_rates(struct vf610_adc *info)
         * BCT (Base Conversion Time): fixed to 25 ADCK cycles for 12 bit mode
         * LSTAdder(Long Sample Time): 3, 5, 7, 9, 13, 17, 21, 25 ADCK cycles
         */
-       adck_rate = ipg_rate / info->adc_feature.clk_div;
        for (i = 0; i < ARRAY_SIZE(vf610_hw_avgs); i++)
                info->sample_freq_avail[i] =
                        adck_rate / (6 + vf610_hw_avgs[i] *
@@ -663,11 +671,13 @@ static int vf610_read_raw(struct iio_dev *indio_dev,
                        break;
                case IIO_TEMP:
                        /*
-                       * Calculate in degree Celsius times 1000
-                       * Using sensor slope of 1.84 mV/°C and
-                       * V at 25°C of 696 mV
-                       */
-                       *val = 25000 - ((int)info->value - 864) * 1000000 / 1840;
+                        * Calculate in degree Celsius times 1000
+                        * Using the typical sensor slope of 1.84 mV/°C
+                        * and VREFH_ADC at 3.3V, V at 25°C of 699 mV
+                        */
+                       *val = 25000 - ((int)info->value - VF610_VTEMP25_3V3) *
+                                       1000000 / VF610_TEMP_SLOPE_COEFF;
+
                        break;
                default:
                        mutex_unlock(&indio_dev->mlock);