Adding the ability for the ads7828 and ads7830 to use the device tree to get thier optional parameters, instead of using platform devices. This allows people using custom boards to also use the ads7828 in a non-default manner.

PATCH In review Sam Povilus 2 participants 2 messages Mar 12, 2017

Subsystems (3)

Device tree bindings I2C subsystem host drivers Hardware monitoring

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Sam Povilus

author

2017-03-12 03:32 UTC #0 lore raw

PATCH v2 1/1 Adding the ability for the ads7828 and ads7830 to use the device tree to get thier optional parameters, instead of using platform devices. This allows people using custom boards to also use the ads7828 in a non-default manner.

Also adding a note to the user if they misconfigure the device's external reference.

Signed-off-by Sam Povilus <[email protected]>

---
 Documentation/devicetree/bindings/hwmon/ads7828.txt    | 18 ++++++++++++++++++
 .../devicetree/bindings/i2c/trivial-devices.txt        |  2 --
 drivers/hwmon/ads7828.c                                | 15 +++++++++++++++
 3 files changed, 33 insertions(+), 2 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/hwmon/ads7828.txt

Documentation/devicetree/bindings/hwmon/ads7828.txt new file +18 -0

new file mode 100644
index 000000000000..7cd786585b51
@@ -0,0 +1,18 @@
+ads7828 properties
+
+Required properties:
+- compatible:
+	Should be one of
+	       ti,ads7828
+	       ti,ads7830
+- reg: I2C address
+
+Optional properties:
+
+- diff_input
+  Set to use the device in differential mode.
+- ext_vref
+  Set to enable the external voltage reference on the device.
+- vref_mv
+  The external reference on the device is set to this as an unsigned integer in
+  milivolts. Must use "ext_vref" for this to have any meaning.

Documentation/devicetree/bindings/i2c/trivial-devices.txt +0 -2

index cdd7b48826c3..87648909f6ce 100644
@@ -163,8 +163,6 @@ st,m41t00		Serial real-time clock (RTC)
 st,m41t62		Serial real-time clock (RTC) with alarm
 st,m41t80		M41T80 - SERIAL ACCESS RTC WITH ALARMS
 taos,tsl2550		Ambient Light Sensor with SMBUS/Two Wire Serial Interface
-ti,ads7828		8-Channels, 12-bit ADC
-ti,ads7830		8-Channels, 8-bit ADC
 ti,tsc2003		I2C Touch-Screen Controller
 ti,tmp102		Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Interface
 ti,tmp103		Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Interface

drivers/hwmon/ads7828.c +15 -0

index ee396ff167d9..05fc0ac06c06 100644
@@ -118,6 +118,7 @@ static int ads7828_probe(struct i2c_client *client,
 	struct ads7828_data *data;
 	struct device *hwmon_dev;
 	unsigned int vref_mv = ADS7828_INT_VREF_MV;
+	unsigned int vref_mv_tmp;
 	bool diff_input = false;
 	bool ext_vref = false;
 	unsigned int regval;

@@ -131,11 +132,25 @@ static int ads7828_probe(struct i2c_client *client,
 		ext_vref = pdata->ext_vref;
 		if (ext_vref && pdata->vref_mv)
 			vref_mv = pdata->vref_mv;
+	} else if (dev->of_node) {
+		if (of_get_property(dev->of_node, "diff_input", NULL))
+			diff_input = true;
+		if (of_get_property(dev->of_node, "ext_vref", NULL))
+			ext_vref = true;
+		if (!of_property_read_u32(dev->of_node, "vref_mv", &vref_mv_tmp)
+		   && ext_vref)
+			vref_mv = vref_mv_tmp;
 	}
 
 	/* Bound Vref with min/max values */
+	vref_mv_tmp = vref_mv;
 	vref_mv = clamp_val(vref_mv, ADS7828_EXT_VREF_MV_MIN,
 			    ADS7828_EXT_VREF_MV_MAX);
+	if (vref_mv_tmp != vref_mv) {
+		pr_info("You used and invalid external vref,"
+			" it has been clamped to %u",
+			vref_mv);
+	}
 
 	/* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
 	if (id->driver_data == ads7828) {

Signature · 1 line

2.11.0

Guenter Roeck

maintainer

2017-03-12 05:43 UTC #1 lore raw

Quoted 3 lines · Sam Povilus

Also adding a note to the user if they misconfigure the device's external reference.

Uuhhh ... ____please____ select a ___much___ shorter subject line. It seems that you put the entire description into the subject line, which is a really bad idea.

Also, it helps, for versioned patches, to describe the changes from one version to another. Please read and follow the guidelines for submitting patches (and consider running your patch through checkpatch.pl).

Devicetree properties need to be submitted to devicetree maintainers. In this case, while I am not an expert, I can say that the added properties are not acceptable; devicetree property name should not include '_'.

Guenter

Quoted 84 lines

Signed-off-by Sam Povilus <[email protected]>

---
 Documentation/devicetree/bindings/hwmon/ads7828.txt    | 18 ++++++++++++++++++
 .../devicetree/bindings/i2c/trivial-devices.txt        |  2 --
 drivers/hwmon/ads7828.c                                | 15 +++++++++++++++
 3 files changed, 33 insertions(+), 2 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/hwmon/ads7828.txt

Documentation/devicetree/bindings/hwmon/ads7828.txt new file +18 -0

new file mode 100644
index 000000000000..7cd786585b51
@@ -0,0 +1,18 @@
+ads7828 properties
+
+Required properties:
+- compatible:
+	Should be one of
+	       ti,ads7828
+	       ti,ads7830
+- reg: I2C address
+
+Optional properties:
+
+- diff_input
+  Set to use the device in differential mode.
+- ext_vref
+  Set to enable the external voltage reference on the device.
+- vref_mv
+  The external reference on the device is set to this as an unsigned integer in
+  milivolts. Must use "ext_vref" for this to have any meaning.

Documentation/devicetree/bindings/i2c/trivial-devices.txt +0 -2

index cdd7b48826c3..87648909f6ce 100644
@@ -163,8 +163,6 @@ st,m41t00		Serial real-time clock (RTC)
 st,m41t62		Serial real-time clock (RTC) with alarm
 st,m41t80		M41T80 - SERIAL ACCESS RTC WITH ALARMS
 taos,tsl2550		Ambient Light Sensor with SMBUS/Two Wire Serial Interface
-ti,ads7828		8-Channels, 12-bit ADC
-ti,ads7830		8-Channels, 8-bit ADC
 ti,tsc2003		I2C Touch-Screen Controller
 ti,tmp102		Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Interface
 ti,tmp103		Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Interface

drivers/hwmon/ads7828.c +15 -0

index ee396ff167d9..05fc0ac06c06 100644
@@ -118,6 +118,7 @@ static int ads7828_probe(struct i2c_client *client,
 	struct ads7828_data *data;
 	struct device *hwmon_dev;
 	unsigned int vref_mv = ADS7828_INT_VREF_MV;
+	unsigned int vref_mv_tmp;
 	bool diff_input = false;
 	bool ext_vref = false;
 	unsigned int regval;

@@ -131,11 +132,25 @@ static int ads7828_probe(struct i2c_client *client,
 		ext_vref = pdata->ext_vref;
 		if (ext_vref && pdata->vref_mv)
 			vref_mv = pdata->vref_mv;
+	} else if (dev->of_node) {
+		if (of_get_property(dev->of_node, "diff_input", NULL))
+			diff_input = true;
+		if (of_get_property(dev->of_node, "ext_vref", NULL))
+			ext_vref = true;
+		if (!of_property_read_u32(dev->of_node, "vref_mv", &vref_mv_tmp)
+		   && ext_vref)
+			vref_mv = vref_mv_tmp;
 	}
 
 	/* Bound Vref with min/max values */
+	vref_mv_tmp = vref_mv;
 	vref_mv = clamp_val(vref_mv, ADS7828_EXT_VREF_MV_MIN,
 			    ADS7828_EXT_VREF_MV_MAX);
+	if (vref_mv_tmp != vref_mv) {
+		pr_info("You used and invalid external vref,"
+			" it has been clamped to %u",
+			vref_mv);
+	}
 
 	/* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
 	if (id->driver_data == ads7828) {