u16 lux;
};
-struct tsl2x7x_prox_stat {
- int min;
- int max;
- int mean;
- unsigned long stddev;
-};
-
struct tsl2x7x_chip_info {
int chan_table_elements;
struct iio_chan_spec channel[4];
return ret;
}
-static void tsl2x7x_prox_calculate(int *data, int length,
- struct tsl2x7x_prox_stat *stat)
-{
- int i;
- int sample_sum;
- int tmp;
-
- if (!length)
- length = 1;
-
- sample_sum = 0;
- stat->min = INT_MAX;
- stat->max = INT_MIN;
- for (i = 0; i < length; i++) {
- sample_sum += data[i];
- stat->min = min(stat->min, data[i]);
- stat->max = max(stat->max, data[i]);
- }
-
- stat->mean = sample_sum / length;
- sample_sum = 0;
- for (i = 0; i < length; i++) {
- tmp = data[i] - stat->mean;
- sample_sum += tmp * tmp;
- }
- stat->stddev = int_sqrt((long)sample_sum / length);
-}
-
-/**
- * tsl2x7x_prox_cal() - Calculates std. and sets thresholds.
- * @indio_dev: pointer to IIO device
- *
- * Calculates a standard deviation based on the samples,
- * and sets the threshold accordingly.
- */
static int tsl2x7x_prox_cal(struct iio_dev *indio_dev)
{
- int prox_history[MAX_SAMPLES_CAL + 1];
- int i, ret;
- struct tsl2x7x_prox_stat prox_stat_data[2];
- struct tsl2x7x_prox_stat *cal;
struct tsl2X7X_chip *chip = iio_priv(indio_dev);
- u8 tmp_irq_settings;
- u8 current_state = chip->tsl2x7x_chip_status;
-
- if (chip->settings.prox_max_samples_cal > MAX_SAMPLES_CAL) {
- dev_err(&chip->client->dev,
- "max prox samples cal is too big: %d\n",
- chip->settings.prox_max_samples_cal);
- chip->settings.prox_max_samples_cal = MAX_SAMPLES_CAL;
- }
-
- /* have to stop to change settings */
- ret = tsl2x7x_chip_off(indio_dev);
- if (ret < 0)
- return ret;
-
- /* Enable proximity detection save just in case prox not wanted yet*/
- tmp_irq_settings = chip->settings.interrupts_en;
- chip->settings.interrupts_en |= TSL2X7X_CNTL_PROX_INT_ENBL;
+ int prox_history[MAX_SAMPLES_CAL + 1];
+ int i, ret, mean, max, sample_sum;
- /*turn on device if not already on*/
- ret = tsl2x7x_chip_on(indio_dev);
- if (ret < 0)
- return ret;
+ if (chip->settings.prox_max_samples_cal < 1 ||
+ chip->settings.prox_max_samples_cal > MAX_SAMPLES_CAL)
+ return -EINVAL;
- /*gather the samples*/
for (i = 0; i < chip->settings.prox_max_samples_cal; i++) {
usleep_range(15000, 17500);
ret = tsl2x7x_get_prox(indio_dev);
if (ret < 0)
return ret;
+
prox_history[i] = chip->prox_data;
- dev_info(&chip->client->dev, "2 i=%d prox data= %d\n",
- i, chip->prox_data);
}
- ret = tsl2x7x_chip_off(indio_dev);
- if (ret < 0)
- return ret;
- cal = &prox_stat_data[PROX_STAT_CAL];
- tsl2x7x_prox_calculate(prox_history,
- chip->settings.prox_max_samples_cal, cal);
- chip->settings.prox_thres_high = (cal->max << 1) - cal->mean;
-
- dev_info(&chip->client->dev, " cal min=%d mean=%d max=%d\n",
- cal->min, cal->mean, cal->max);
- dev_info(&chip->client->dev,
- "%s proximity threshold set to %d\n",
- chip->client->name, chip->settings.prox_thres_high);
-
- /* back to the way they were */
- chip->settings.interrupts_en = tmp_irq_settings;
- if (current_state == TSL2X7X_CHIP_WORKING) {
- ret = tsl2x7x_chip_on(indio_dev);
- if (ret < 0)
- return ret;
+ sample_sum = 0;
+ max = INT_MIN;
+ for (i = 0; i < chip->settings.prox_max_samples_cal; i++) {
+ sample_sum += prox_history[i];
+ max = max(max, prox_history[i]);
}
+ mean = sample_sum / chip->settings.prox_max_samples_cal;
- return 0;
+ chip->settings.prox_thres_high = (max << 1) - mean;
+
+ return tsl2x7x_invoke_change(indio_dev);
}
static ssize_t