[PATCH 3/7] thermal: qcom: qcom-spmi-adc-tm5-gen3: Add support for QCOM PMIC5 Gen4 ADC

[Jishnu Prakash]

PMIC5 Gen4 ADC is similar to PMIC5 Gen3 ADC, with several changes made
for improved performance, mostly at the hardware level.

One significant software change is that ratiometric conversion resolution
has been increased from 14 bits to 16 bits. Add a reverse scaling function
for Gen4 ADC thermistor channels.

In the latest PMIC arbiter version (v8), there can be up to 4 buses
under the PMIC arbiter and 32 PMICs under each bus. In order to
support communication between ADC on the master PMIC and ADCs on any
of the other PMICs, a field of width 2 bits is added for bus index
and the bits for SID are extended from 4 to 5 bits, in the SID
register. Add support for this.

Co-developed-by: Anjelique Melendez <anjelique.melendez@xxxxxxxxxxxxxxxx>
Signed-off-by: Anjelique Melendez <anjelique.melendez@xxxxxxxxxxxxxxxx>
Signed-off-by: Jishnu Prakash <jishnu.prakash@xxxxxxxxxxxxxxxx>
---
 drivers/iio/adc/qcom-vadc-common.c            | 11 +++++++++++
 drivers/thermal/qcom/qcom-spmi-adc-tm5-gen3.c | 19 ++++++++++++++-----
 include/linux/iio/adc/qcom-vadc-common.h      |  2 ++
 3 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/adc/qcom-vadc-common.c b/drivers/iio/adc/qcom-vadc-common.c
index cb23d0d178c7..25bd4622c389 100644
--- a/drivers/iio/adc/qcom-vadc-common.c
+++ b/drivers/iio/adc/qcom-vadc-common.c
@@ -720,6 +720,17 @@ u16 qcom_adc_tm5_gen2_temp_res_scale(int temp)
 }
 EXPORT_SYMBOL(qcom_adc_tm5_gen2_temp_res_scale);
 
+u16 qcom_adc_tm5_gen4_temp_res_scale(int temp)
+{
+	s64 resistance;
+
+	resistance = qcom_vadc_map_temp_voltage(adcmap7_100k,
+						ARRAY_SIZE(adcmap7_100k), temp);
+
+	return div64_s64(resistance * RATIO_MAX_ADC5_GEN4, resistance + R_PU_100K);
+}
+EXPORT_SYMBOL(qcom_adc_tm5_gen4_temp_res_scale);
+
 int qcom_adc5_hw_scale(enum vadc_scale_fn_type scaletype,
 		    unsigned int prescale_ratio,
 		    const struct adc5_data *data,
diff --git a/drivers/thermal/qcom/qcom-spmi-adc-tm5-gen3.c b/drivers/thermal/qcom/qcom-spmi-adc-tm5-gen3.c
index 9cf552d36868..80e820b6dc4b 100644
--- a/drivers/thermal/qcom/qcom-spmi-adc-tm5-gen3.c
+++ b/drivers/thermal/qcom/qcom-spmi-adc-tm5-gen3.c
@@ -207,15 +207,23 @@ static int adc_tm5_gen3_disable_channel(struct adc_tm5_gen3_channel_props *prop)
 			       ADC5_GEN3_CONV_REQ, &val, sizeof(val));
 }
 
+typedef u16 (*temp_res_scale)(int temp);
+
 static int adc_tm5_gen3_configure(struct adc_tm5_gen3_channel_props *prop,
 				  int low_temp, int high_temp)
 {
 	struct adc_tm5_gen3_chip *adc_tm5 = prop->chip;
 	u8 buf[ADC_TM5_GEN3_CONFIG_REGS];
+	temp_res_scale tm_scal_fn;
 	u8 conv_req;
 	u16 adc_code;
 	int ret;
 
+	if (prop->common_props.generation == ADC5_GEN4)
+		tm_scal_fn = qcom_adc_tm5_gen4_temp_res_scale;
+	else
+		tm_scal_fn = qcom_adc_tm5_gen2_temp_res_scale;
+
 	ret = adc5_gen3_poll_wait_hs(adc_tm5->dev_data, prop->sdam_index);
 	if (ret < 0)
 		return ret;
@@ -225,8 +233,9 @@ static int adc_tm5_gen3_configure(struct adc_tm5_gen3_channel_props *prop,
 	if (ret < 0)
 		return ret;
 
-	/* Write SID */
-	buf[0] = FIELD_PREP(ADC5_GEN3_SID_MASK, prop->common_props.sid);
+	/* Write SID and bus_id*/
+	buf[0] = FIELD_PREP(ADC5_GEN4_BUS_INDEX_MASK, prop->common_props.bus_index) |
+		 FIELD_PREP(ADC5_GEN4_SID_MASK, prop->common_props.sid);
 
 	/* Select TM channel and indicate there is an actual conversion request */
 	buf[1] = ADC5_GEN3_CHAN_CONV_REQ | prop->tm_chan_index;
@@ -252,7 +261,7 @@ static int adc_tm5_gen3_configure(struct adc_tm5_gen3_channel_props *prop,
 	/* High temperature corresponds to low voltage threshold */
 	prop->low_thr_en = (high_temp != INT_MAX);
 	if (prop->low_thr_en) {
-		adc_code = qcom_adc_tm5_gen2_temp_res_scale(high_temp);
+		adc_code = tm_scal_fn(high_temp);
 		put_unaligned_le16(adc_code, &buf[8]);
 		buf[7] |= ADC5_GEN3_LOW_THR_INT_EN;
 	}
@@ -260,7 +269,7 @@ static int adc_tm5_gen3_configure(struct adc_tm5_gen3_channel_props *prop,
 	/* Low temperature corresponds to high voltage threshold */
 	prop->high_thr_en = (low_temp != -INT_MAX);
 	if (prop->high_thr_en) {
-		adc_code = qcom_adc_tm5_gen2_temp_res_scale(low_temp);
+		adc_code = tm_scal_fn(low_temp);
 		put_unaligned_le16(adc_code, &buf[10]);
 		buf[7] |= ADC5_GEN3_HIGH_THR_INT_EN;
 	}
@@ -306,7 +315,7 @@ static int adc_tm5_register_tzd(struct adc_tm5_gen3_chip *adc_tm5)
 	int ret;
 
 	for (int i = 0; i < adc_tm5->nchannels; i++) {
-		channel = ADC5_GEN3_V_CHAN(adc_tm5->chan_props[i].common_props);
+		channel = ADC5_GEN4_V_CHAN(adc_tm5->chan_props[i].common_props);
 		tzd = devm_thermal_of_zone_register(adc_tm5->dev, channel,
 						    &adc_tm5->chan_props[i],
 						    &adc_tm_ops);
diff --git a/include/linux/iio/adc/qcom-vadc-common.h b/include/linux/iio/adc/qcom-vadc-common.h
index 4be682083843..55efad27ed73 100644
--- a/include/linux/iio/adc/qcom-vadc-common.h
+++ b/include/linux/iio/adc/qcom-vadc-common.h
@@ -159,6 +159,8 @@ u16 qcom_adc_tm5_temp_volt_scale(unsigned int prescale_ratio,
 
 u16 qcom_adc_tm5_gen2_temp_res_scale(int temp);
 
+u16 qcom_adc_tm5_gen4_temp_res_scale(int temp);
+
 int qcom_adc5_prescaling_from_dt(u32 num, u32 den);
 
 int qcom_adc5_hw_settle_time_from_dt(u32 value, const unsigned int *hw_settle);

-- 
2.43.0