Subject: [PATCH v3 18/30] iio: adc: sun4i-gpadc-iio: rework: support multiple sensors

From: [email-masked] (Philipp Rossak)
Date: Thu, 30 Aug 2018 17:45:06 +0200

For adding newer sensor some basic rework of the code is necessary.

This patch reworks the driver to be able to handle more than one
thermal sensor. Newer SoC like the A80 have 4 thermal sensors.
Because of this the maximal sensor count value was set to 4.

The sensor_id value is set during sensor registration and is for each
registered sensor indiviual. This makes it able to differntiate the
sensors when the value is read from the register.

In function sun4i_gpadc_read_raw(), the sensor number of the ths sensor
was directly set to 0 (sun4i_gpadc_temp_read(x,x,0)). This selects
in the temp_read function automatically sensor 0. A check for the
sensor_id is here not required since the old sensors only have one
thermal sensor. In addition to that is the sun4i_gpadc_read_raw()
function only used by the "older" sensors (before A33) where the
thermal sensor was a cobination of an adc and a thermal sensor.

Signed-off-by: Philipp Rossak <[email-masked]>
---
 drivers/iio/adc/sun4i-gpadc-iio.c   | 63 +++++++++++++++++++++++++------------
 include/linux/iio/adc/sun4i-gpadc.h |  3 ++
 2 files changed, 46 insertions(+), 20 deletions(-)

diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c
index c12de48c4e86..18ab72e52d78 100644
--- a/drivers/iio/adc/sun4i-gpadc-iio.c
+++ b/drivers/iio/adc/sun4i-gpadc-iio.c
@@ -69,6 +69,7 @@ struct gpadc_data {
 	bool		has_bus_rst;
 	bool		has_mod_clk;
 	u32		temp_data_base;
+	int		sensor_count;
 };
 
 static irqreturn_t sun4i_gpadc_data_irq_handler(int irq, void *dev_id);
@@ -84,6 +85,7 @@ static const struct gpadc_data sun4i_gpadc_data = {
 	.ths_irq_thread = sun4i_gpadc_data_irq_handler,
 	.support_irq = true,
 	.temp_data_base = SUN4I_GPADC_TEMP_DATA,
+	.sensor_count = 1,
 };
 
 static const struct gpadc_data sun5i_gpadc_data = {
@@ -97,6 +99,7 @@ static const struct gpadc_data sun5i_gpadc_data = {
 	.ths_irq_thread = sun4i_gpadc_data_irq_handler,
 	.support_irq = true,
 	.temp_data_base = SUN4I_GPADC_TEMP_DATA,
+	.sensor_count = 1,
 };
 
 static const struct gpadc_data sun6i_gpadc_data = {
@@ -110,6 +113,7 @@ static const struct gpadc_data sun6i_gpadc_data = {
 	.ths_irq_thread = sun4i_gpadc_data_irq_handler,
 	.support_irq = true,
 	.temp_data_base = SUN4I_GPADC_TEMP_DATA,
+	.sensor_count = 1,
 };
 
 static const struct gpadc_data sun8i_a33_gpadc_data = {
@@ -117,6 +121,13 @@ static const struct gpadc_data sun8i_a33_gpadc_data = {
 	.temp_scale = 162,
 	.tp_mode_en = SUN8I_A33_GPADC_CTRL1_CHOP_TEMP_EN,
 	.temp_data_base = SUN4I_GPADC_TEMP_DATA,
+	.sensor_count = 1,
+};
+
+struct sun4i_sensor_tzd {
+	struct sun4i_gpadc_iio		*info;
+	struct thermal_zone_device	*tzd;
+	unsigned int			sensor_id;
 };
 
 struct sun4i_gpadc_iio {
@@ -130,7 +141,7 @@ struct sun4i_gpadc_iio {
 	const struct gpadc_data		*data;
 	/* prevents concurrent reads of temperature and ADC */
 	struct mutex			mutex;
-	struct thermal_zone_device	*tzd;
+	struct sun4i_sensor_tzd		tzds[MAX_SENSOR_COUNT];
 	struct device			*sensor_device;
 	struct clk			*bus_clk;
 	struct clk			*mod_clk;
@@ -280,7 +291,8 @@ static int sun4i_gpadc_adc_read(struct iio_dev *indio_dev, int channel,
 			SUN4I_GPADC_IRQ_FIFO_DATA);
 }
 
-static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val)
+static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val,
+				int sensor)
 {
 	struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
 
@@ -290,7 +302,8 @@ static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val)
 
 	pm_runtime_get_sync(indio_dev->dev.parent);
 
-	regmap_read(info->regmap, info->data->temp_data_base, val);
+	regmap_read(info->regmap, info->data->temp_data_base + 0x4 * sensor,
+			val);
 
 	pm_runtime_mark_last_busy(indio_dev->dev.parent);
 	pm_runtime_put_autosuspend(indio_dev->dev.parent);
@@ -334,7 +347,7 @@ static int sun4i_gpadc_read_raw(struct iio_dev *indio_dev,
 			ret = sun4i_gpadc_adc_read(indio_dev, chan->channel,
 						   val);
 		else
-			ret = sun4i_gpadc_temp_read(indio_dev, val);
+			ret = sun4i_gpadc_temp_read(indio_dev, val, 0);
 
 		if (ret)
 			return ret;
@@ -420,10 +433,11 @@ static int sun4i_gpadc_runtime_resume(struct device *dev)
 
 static int sun4i_gpadc_get_temp(void *data, int *temp)
 {
-	struct sun4i_gpadc_iio *info = data;
+	struct sun4i_sensor_tzd *tzd = data;
+	struct sun4i_gpadc_iio *info = tzd->info;
 	int val, scale, offset;
 
-	if (sun4i_gpadc_temp_read(info->indio_dev, &val))
+	if (sun4i_gpadc_temp_read(info->indio_dev, &val, tzd->sensor_id))
 		return -ETIMEDOUT;
 
 	sun4i_gpadc_temp_scale(info->indio_dev, &scale);
@@ -569,7 +583,7 @@ static int sun4i_gpadc_probe(struct platform_device *pdev)
 {
 	struct sun4i_gpadc_iio *info;
 	struct iio_dev *indio_dev;
-	int ret;
+	int ret, i;
 
 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
 	if (!indio_dev)
@@ -603,18 +617,24 @@ static int sun4i_gpadc_probe(struct platform_device *pdev)
 	pm_runtime_set_suspended(&pdev->dev);
 	pm_runtime_enable(&pdev->dev);
 
-	info->tzd = thermal_zone_of_sensor_register(info->sensor_device,
-						    0, info,
-						    &sun4i_ts_tz_ops);
-	/*
-	 * Do not fail driver probing when failing to register in
-	 * thermal because no thermal DT node is found.
-	 */
-	if (IS_ERR(info->tzd) && PTR_ERR(info->tzd) != -ENODEV) {
-		dev_err(&pdev->dev,
-			"could not register thermal sensor: %ld\n",
-			PTR_ERR(info->tzd));
-		return PTR_ERR(info->tzd);
+	for (i = 0; i < info->data->sensor_count; i++) {
+		info->tzds[i].info = info;
+		info->tzds[i].sensor_id = i;
+
+		info->tzds[i].tzd = thermal_zone_of_sensor_register(
+				info->sensor_device,
+				i, &info->tzds[i], &sun4i_ts_tz_ops);
+		/*
+		 * Do not fail driver probing when failing to register in
+		 * thermal because no thermal DT node is found.
+		 */
+		if (IS_ERR(info->tzds[i].tzd) && \
+				PTR_ERR(info->tzds[i].tzd) != -ENODEV) {
+			dev_err(&pdev->dev,
+				"could not register thermal sensor: %ld\n",
+				PTR_ERR(info->tzds[i].tzd));
+			return PTR_ERR(info->tzds[i].tzd);
+		}
 	}
 
 	ret = devm_iio_device_register(&pdev->dev, indio_dev);
@@ -639,11 +659,14 @@ static int sun4i_gpadc_remove(struct platform_device *pdev)
 {
 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 	struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
+	int i;
 
 	pm_runtime_put(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 
-	thermal_zone_of_sensor_unregister(info->sensor_device, info->tzd);
+	for (i = 0; i < info->data->sensor_count; i++)
+		thermal_zone_of_sensor_unregister(info->sensor_device,
+						  info->tzds[i].tzd);
 
 	if (!info->data->support_irq)
 		iio_map_array_unregister(indio_dev);
diff --git a/include/linux/iio/adc/sun4i-gpadc.h b/include/linux/iio/adc/sun4i-gpadc.h
index d6850f39dcfb..99feeba28105 100644
--- a/include/linux/iio/adc/sun4i-gpadc.h
+++ b/include/linux/iio/adc/sun4i-gpadc.h
@@ -99,4 +99,7 @@
 	.datasheet_name = _name,				\
 }
 
+/* SUNXI_THS COMMON REGISTERS + DEFINES */
+#define MAX_SENSOR_COUNT				4
+
 #endif
-- 
2.11.0