Skip to content

Commit

Permalink
hwmon: (tmp513) Use SI constants from units.h
Browse files Browse the repository at this point in the history
MILLI and MICRO may be used in the driver to make code more robust
against possible miscalculations.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231128180654.395692-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
  • Loading branch information
Andy Shevchenko authored and Guenter Roeck committed Dec 11, 2023
1 parent df98976 commit f07f9d2
Showing 1 changed file with 10 additions and 11 deletions.
21 changes: 10 additions & 11 deletions drivers/hwmon/tmp513.c
Original file line number Diff line number Diff line change
Expand Up @@ -32,6 +32,7 @@
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/units.h>

// Common register definition
#define TMP51X_SHUNT_CONFIG 0x00
Expand Down Expand Up @@ -101,8 +102,8 @@
#define TMP51X_REMOTE_TEMP_LIMIT_2_POS 8
#define TMP513_REMOTE_TEMP_LIMIT_3_POS 7

#define TMP51X_VBUS_RANGE_32V 32000000
#define TMP51X_VBUS_RANGE_16V 16000000
#define TMP51X_VBUS_RANGE_32V (32 * MICRO)
#define TMP51X_VBUS_RANGE_16V (16 * MICRO)

// Max and Min value
#define MAX_BUS_VOLTAGE_32_LIMIT 32764
Expand Down Expand Up @@ -204,7 +205,7 @@ static int tmp51x_get_value(struct tmp51x_data *data, u8 reg, u8 pos,
* on the pga gain setting. 1lsb = 10uV
*/
*val = sign_extend32(regval, 17 - tmp51x_get_pga_shift(data));
*val = DIV_ROUND_CLOSEST(*val * 10000, data->shunt_uohms);
*val = DIV_ROUND_CLOSEST(*val * 10 * MILLI, data->shunt_uohms);
break;
case TMP51X_BUS_VOLTAGE_RESULT:
case TMP51X_BUS_VOLTAGE_H_LIMIT:
Expand All @@ -220,7 +221,7 @@ static int tmp51x_get_value(struct tmp51x_data *data, u8 reg, u8 pos,
case TMP51X_BUS_CURRENT_RESULT:
// Current = (ShuntVoltage * CalibrationRegister) / 4096
*val = sign_extend32(regval, 16) * data->curr_lsb_ua;
*val = DIV_ROUND_CLOSEST(*val, 1000);
*val = DIV_ROUND_CLOSEST(*val, MILLI);
break;
case TMP51X_LOCAL_TEMP_RESULT:
case TMP51X_REMOTE_TEMP_RESULT_1:
Expand Down Expand Up @@ -260,7 +261,7 @@ static int tmp51x_set_value(struct tmp51x_data *data, u8 reg, long val)
* The user enter current value and we convert it to
* voltage. 1lsb = 10uV
*/
val = DIV_ROUND_CLOSEST(val * data->shunt_uohms, 10000);
val = DIV_ROUND_CLOSEST(val * data->shunt_uohms, 10 * MILLI);
max_val = U16_MAX >> tmp51x_get_pga_shift(data);
regval = clamp_val(val, -max_val, max_val);
break;
Expand Down Expand Up @@ -550,18 +551,16 @@ static int tmp51x_calibrate(struct tmp51x_data *data)
if (data->shunt_uohms == 0)
return regmap_write(data->regmap, TMP51X_SHUNT_CALIBRATION, 0);

max_curr_ma = DIV_ROUND_CLOSEST_ULL(vshunt_max * 1000 * 1000,
data->shunt_uohms);
max_curr_ma = DIV_ROUND_CLOSEST_ULL(vshunt_max * MICRO, data->shunt_uohms);

/*
* Calculate the minimal bit resolution for the current and the power.
* Those values will be used during register interpretation.
*/
data->curr_lsb_ua = DIV_ROUND_CLOSEST_ULL(max_curr_ma * 1000, 32767);
data->curr_lsb_ua = DIV_ROUND_CLOSEST_ULL(max_curr_ma * MILLI, 32767);
data->pwr_lsb_uw = 20 * data->curr_lsb_ua;

div = DIV_ROUND_CLOSEST_ULL(data->curr_lsb_ua * data->shunt_uohms,
1000 * 1000);
div = DIV_ROUND_CLOSEST_ULL(data->curr_lsb_ua * data->shunt_uohms, MICRO);

return regmap_write(data->regmap, TMP51X_SHUNT_CALIBRATION,
DIV_ROUND_CLOSEST(40960, div));
Expand Down Expand Up @@ -678,7 +677,7 @@ static int tmp51x_read_properties(struct device *dev, struct tmp51x_data *data)
data->max_channels - 1);

// Check if shunt value is compatible with pga-gain
if (data->shunt_uohms > data->pga_gain * 40 * 1000 * 1000) {
if (data->shunt_uohms > data->pga_gain * 40 * MICRO) {
return dev_err_probe(dev, -EINVAL,
"shunt-resistor: %u too big for pga_gain: %u\n",
data->shunt_uohms, data->pga_gain);
Expand Down

0 comments on commit f07f9d2

Please sign in to comment.