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path: root/drivers/iio/adc/max9611.c
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Diffstat (limited to 'drivers/iio/adc/max9611.c')
-rw-r--r--drivers/iio/adc/max9611.c52
1 files changed, 21 insertions, 31 deletions
diff --git a/drivers/iio/adc/max9611.c b/drivers/iio/adc/max9611.c
index da073d72f649..04d5ff7d2c8e 100644
--- a/drivers/iio/adc/max9611.c
+++ b/drivers/iio/adc/max9611.c
@@ -89,6 +89,12 @@
#define MAX9611_TEMP_SCALE_NUM 1000000
#define MAX9611_TEMP_SCALE_DIV 2083
+/*
+ * Conversion time is 2 ms (typically) at Ta=25 degreeC
+ * No maximum value is known, so play it safe.
+ */
+#define MAX9611_CONV_TIME_US_RANGE 3000, 3300
+
struct max9611_dev {
struct device *dev;
struct i2c_client *i2c_client;
@@ -109,22 +115,17 @@ enum max9611_conf_ids {
* where data shall be read from
*/
static const unsigned int max9611_mux_conf[][2] = {
- /* CONF_SENSE_1x */
- { MAX9611_MUX_SENSE_1x, MAX9611_REG_CSA_DATA },
- /* CONF_SENSE_4x */
- { MAX9611_MUX_SENSE_4x, MAX9611_REG_CSA_DATA },
- /* CONF_SENSE_8x */
- { MAX9611_MUX_SENSE_8x, MAX9611_REG_CSA_DATA },
- /* CONF_IN_VOLT */
- { MAX9611_INPUT_VOLT, MAX9611_REG_RS_DATA },
- /* CONF_TEMP */
- { MAX9611_MUX_TEMP, MAX9611_REG_TEMP_DATA },
+ [CONF_SENSE_1x] = { MAX9611_MUX_SENSE_1x, MAX9611_REG_CSA_DATA },
+ [CONF_SENSE_4x] = { MAX9611_MUX_SENSE_4x, MAX9611_REG_CSA_DATA },
+ [CONF_SENSE_8x] = { MAX9611_MUX_SENSE_8x, MAX9611_REG_CSA_DATA },
+ [CONF_IN_VOLT] = { MAX9611_INPUT_VOLT, MAX9611_REG_RS_DATA },
+ [CONF_TEMP] = { MAX9611_MUX_TEMP, MAX9611_REG_TEMP_DATA },
};
enum max9611_csa_gain {
- CSA_GAIN_1x,
- CSA_GAIN_4x,
- CSA_GAIN_8x,
+ CSA_GAIN_1x = CONF_SENSE_1x,
+ CSA_GAIN_4x = CONF_SENSE_4x,
+ CSA_GAIN_8x = CONF_SENSE_8x,
};
enum max9611_csa_gain_params {
@@ -142,18 +143,9 @@ enum max9611_csa_gain_params {
* value; use this structure to retrieve the correct LSB and offset values.
*/
static const unsigned int max9611_gain_conf[][2] = {
- { /* [0] CSA_GAIN_1x */
- MAX9611_CSA_1X_LSB_nV,
- MAX9611_CSA_1X_OFFS_RAW,
- },
- { /* [1] CSA_GAIN_4x */
- MAX9611_CSA_4X_LSB_nV,
- MAX9611_CSA_4X_OFFS_RAW,
- },
- { /* [2] CSA_GAIN_8x */
- MAX9611_CSA_8X_LSB_nV,
- MAX9611_CSA_8X_OFFS_RAW,
- },
+ [CSA_GAIN_1x] = { MAX9611_CSA_1X_LSB_nV, MAX9611_CSA_1X_OFFS_RAW, },
+ [CSA_GAIN_4x] = { MAX9611_CSA_4X_LSB_nV, MAX9611_CSA_4X_OFFS_RAW, },
+ [CSA_GAIN_8x] = { MAX9611_CSA_8X_LSB_nV, MAX9611_CSA_8X_OFFS_RAW, },
};
enum max9611_chan_addrs {
@@ -236,11 +228,9 @@ static int max9611_read_single(struct max9611_dev *max9611,
return ret;
}
- /*
- * need a delay here to make register configuration
- * stabilize. 1 msec at least, from empirical testing.
- */
- usleep_range(1000, 2000);
+ /* need a delay here to make register configuration stabilize. */
+
+ usleep_range(MAX9611_CONV_TIME_US_RANGE);
ret = i2c_smbus_read_word_swapped(max9611->i2c_client, reg_addr);
if (ret < 0) {
@@ -507,7 +497,7 @@ static int max9611_init(struct max9611_dev *max9611)
MAX9611_REG_CTRL2, 0);
return ret;
}
- usleep_range(1000, 2000);
+ usleep_range(MAX9611_CONV_TIME_US_RANGE);
return 0;
}
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