/**
* ti_bandgap_get_trend() - To fetch the temperature trend of a sensor
* @bgp: pointer to struct ti_bandgap
* @id: id of the individual sensor
* @trend: Pointer to trend.
*
* This function needs to be called to fetch the temperature trend of a
* Particular sensor. The function computes the difference in temperature
* w.r.t time. For the bandgaps with built in history buffer the temperatures
* are read from the buffer and for those without the Buffer -ENOTSUPP is
* returned.
*
* Return: 0 if no error, else return corresponding error. If no
* error then the trend value is passed on to trend parameter
*/
int ti_bandgap_get_trend(struct ti_bandgap *bgp, int id, int *trend)
{
struct temp_sensor_registers *tsr;
u32 temp1, temp2, reg1, reg2;
int t1, t2, interval, ret = 0;
ret = ti_bandgap_validate(bgp, id);
if (ret)
goto exit;
if (!TI_BANDGAP_HAS(bgp, HISTORY_BUFFER) ||
!TI_BANDGAP_HAS(bgp, FREEZE_BIT)) {
ret = -ENOTSUPP;
goto exit;
}
tsr = bgp->conf->sensors[id].registers;
/* Freeze and read the last 2 valid readings */
reg1 = tsr->ctrl_dtemp_1;
reg2 = tsr->ctrl_dtemp_2;
/* read temperature from history buffer */
temp1 = ti_bandgap_readl(bgp, reg1);
temp1 &= tsr->bgap_dtemp_mask;
temp2 = ti_bandgap_readl(bgp, reg2);
temp2 &= tsr->bgap_dtemp_mask;
/* Convert from adc values to mCelsius temperature */
ret = ti_bandgap_adc_to_mcelsius(bgp, temp1, &t1);
if (ret)
goto exit;
ret = ti_bandgap_adc_to_mcelsius(bgp, temp2, &t2);
if (ret)
goto exit;
/* Fetch the update interval */
ret = ti_bandgap_read_update_interval(bgp, id, &interval);
if (ret || !interval)
goto exit;
*trend = (t1 - t2) / interval;
dev_dbg(bgp->dev, "The temperatures are t1 = %d and t2 = %d and trend =%d\n",
t1, t2, *trend);
exit:
return ret;
}
/**
* ti_bandgap_add_hyst() - add hysteresis (in mCelsius) to an ADC value
* @bgp: struct ti_bandgap pointer
* @adc_val: temperature value in ADC representation
* @hyst_val: hysteresis value in mCelsius
* @sum: address where to write the resulting temperature (in ADC scale)
*
* Adds an hysteresis value (in mCelsius) to a ADC temperature value.
*
* Return: 0 on success, -ERANGE otherwise.
*/
static
int ti_bandgap_add_hyst(struct ti_bandgap *bgp, int adc_val, int hyst_val,
u32 *sum)
{
int temp, ret;
/*
* Need to add in the mcelsius domain, so we have a temperature
* the conv_table range
*/
ret = ti_bandgap_adc_to_mcelsius(bgp, adc_val, &temp);
if (ret < 0)
goto exit;
temp += hyst_val;
ret = ti_bandgap_mcelsius_to_adc(bgp, temp, sum);
exit:
return ret;
}
/**
* ti_bandgap_read_temperature() - report current temperature
* @bgp: pointer to bandgap instance
* @id: sensor id
* @temperature: resulting temperature
*
* Return: 0 on success or the proper error code
*/
int ti_bandgap_read_temperature(struct ti_bandgap *bgp, int id,
int *temperature)
{
u32 temp;
int ret;
ret = ti_bandgap_validate(bgp, id);
if (ret)
return ret;
spin_lock(&bgp->lock);
temp = ti_bandgap_read_temp(bgp, id);
spin_unlock(&bgp->lock);
ret |= ti_bandgap_adc_to_mcelsius(bgp, temp, &temp);
if (ret)
return -EIO;
*temperature = temp;
return 0;
}
/**
* _ti_bandgap_read_threshold() - helper to read TALERT t_cold or t_hot
* @bgp: struct ti_bandgap pointer
* @id: bandgap sensor id
* @val: value (mCelsius) of a threshold
* @hot: desired threshold to be read. true if threshold hot, false if
* threshold cold
*
* It will fetch the required thresholds (hot and cold) for TALERT signal.
* This function can be used to read t_hot or t_cold, depending on @hot value.
* Call this function only if bandgap features HAS(TALERT).
*
* Return: 0 if no error, -ENOTSUPP if it has no TALERT support, or the
* corresponding error value if some operation fails.
*/
static int _ti_bandgap_read_threshold(struct ti_bandgap *bgp, int id,
int *val, bool hot)
{
struct temp_sensor_registers *tsr;
u32 temp, mask;
int ret = 0;
ret = ti_bandgap_validate(bgp, id);
if (ret)
goto exit;
if (!TI_BANDGAP_HAS(bgp, TALERT)) {
ret = -ENOTSUPP;
goto exit;
}
tsr = bgp->conf->sensors[id].registers;
if (hot)
mask = tsr->threshold_thot_mask;
else
mask = tsr->threshold_tcold_mask;
temp = ti_bandgap_readl(bgp, tsr->bgap_threshold);
temp = (temp & mask) >> __ffs(mask);
ret |= ti_bandgap_adc_to_mcelsius(bgp, temp, &temp);
if (ret) {
dev_err(bgp->dev, "failed to read thot\n");
ret = -EIO;
goto exit;
}
*val = temp;
exit:
return ret;
}
