drivers: thermal: tsens: simplify get_temp_tsens_v2 routine

#define TM_Sn_STATUS_OFF		0x00a0

#define TM_TRDY_OFF			0x00e4

#define LAST_TEMP_MASK		0xfff

static int get_temp_tsens_v2(struct tsens_priv *priv, int id, int *temp)

static int get_temp_tsens_v2(struct tsens_priv *priv, int i, int *temp)

{

	struct tsens_sensor *s = &priv->sensor[id];

	struct tsens_sensor *s = &priv->sensor[i];

	u32 temp_idx = LAST_TEMP_0 + s->hw_id;

	u32 valid_idx = VALID_0 + s->hw_id;

	u32 last_temp = 0, last_temp2 = 0, last_temp3 = 0, valid;

	u32 last_temp = 0, valid, mask;

	int ret;

	ret = regmap_field_read(priv->rf[temp_idx], &last_temp);

	if (ret)

		return ret;

	ret = regmap_field_read(priv->rf[valid_idx], &valid);

	if (ret)

		return ret;

	if (valid)

		goto done;

	/* Try a second time */

	while (!valid) {

		/* Valid bit is 0 for 6 AHB clock cycles.

		 * At 19.2MHz, 1 AHB clock is ~60ns.

		 * We should enter this loop very, very rarely.

		 */

		ndelay(400);

		ret = regmap_field_read(priv->rf[valid_idx], &valid);

		if (ret)

			return ret;

	ret = regmap_field_read(priv->rf[temp_idx], &last_temp2);

	if (ret)

		return ret;

	if (valid) {

		last_temp = last_temp2;

		goto done;

	}

	/* Try a third/last time */

	ret = regmap_field_read(priv->rf[valid_idx], &valid);

	if (ret)

		return ret;

	ret = regmap_field_read(priv->rf[temp_idx], &last_temp3);

	/* Valid bit is set, OK to read the temperature */

	ret = regmap_field_read(priv->rf[temp_idx], &last_temp);

	if (ret)

		return ret;

	if (valid) {

		last_temp = last_temp3;

		goto done;

	}

	if (last_temp == last_temp2)

		last_temp = last_temp2;

	else if (last_temp2 == last_temp3)

		last_temp = last_temp3;

done:

	mask = GENMASK(priv->fields[LAST_TEMP_0].msb,

		       priv->fields[LAST_TEMP_0].lsb);

	/* Convert temperature from deciCelsius to milliCelsius */

	*temp = sign_extend32(last_temp, fls(LAST_TEMP_MASK) - 1) * 100;

	*temp = sign_extend32(last_temp, fls(mask) - 1) * 100;

	return 0;

}