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Subject[PATCH v4 6/8] iio: adc: add STMPE ADC devicetree bindings
Date
From: Stefan Agner <stefan@agner.ch>

This adds the devicetree bindings for the STMPE ADC. And corrects a
typo in st,sample-time it is rather "6 -> 124 clocks" according
to the datasheet and not 144.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Max Krummenacher <max.krummenacher@toradex.com>
Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com>
---

Changes in v4:
- Put reformatting in a separate precursor patch.

Changes in v3:
- Reformatted documentation for touchscreen to use tabs and have a better
overview of the settings.
- Added note which adc-settings will take precedence.
- changed typo in sample-time setting from 144 clocks to 124 clocks, as stated
in the datasheet.

Changes in v2:
- Moved the bindings for ADC to the overlying mfd.
- Reformatted for better readability

.../devicetree/bindings/iio/adc/stmpe-adc.txt | 21 ++++++++++++
.../bindings/input/touchscreen/stmpe.txt | 32 +++++++++----------
.../devicetree/bindings/mfd/stmpe.txt | 14 ++++++++
3 files changed, 51 insertions(+), 16 deletions(-)
create mode 100644 Documentation/devicetree/bindings/iio/adc/stmpe-adc.txt

diff --git a/Documentation/devicetree/bindings/iio/adc/stmpe-adc.txt b/Documentation/devicetree/bindings/iio/adc/stmpe-adc.txt
new file mode 100644
index 000000000000..480e66422625
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/stmpe-adc.txt
@@ -0,0 +1,21 @@
+STMPE ADC driver
+----------------
+
+Required properties:
+ - compatible: "st,stmpe-adc"
+
+Optional properties:
+Note that the ADC is shared with the STMPE touchscreen. ADC related settings
+have to be done in the mfd.
+- st,norequest-mask: bitmask specifying which ADC channels should _not_ be
+ requestable due to different usage (e.g. touch)
+
+Node name must be stmpe_adc and should be child node of stmpe node to
+which it belongs.
+
+Example:
+
+ stmpe_adc {
+ compatible = "st,stmpe-adc";
+ st,norequest-mask = <0x0F>; /* dont use ADC CH3-0 */
+ };
diff --git a/Documentation/devicetree/bindings/input/touchscreen/stmpe.txt b/Documentation/devicetree/bindings/input/touchscreen/stmpe.txt
index 1d3f84308142..8e2b240882fa 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/stmpe.txt
+++ b/Documentation/devicetree/bindings/input/touchscreen/stmpe.txt
@@ -5,18 +5,6 @@ Required properties:
- compatible: "st,stmpe-ts"

Optional properties:
-- st,sample-time : ADC conversion time in number of clock.
- 0 -> 36 clocks 4 -> 80 clocks (recommended)
- 1 -> 44 clocks 5 -> 96 clocks
- 2 -> 56 clocks 6 -> 144 clocks
- 3 -> 64 clocks
-- st,mod-12b : ADC Bit mode
- 0 -> 10bit ADC 1 -> 12bit ADC
-- st,ref-sel : ADC reference source
- 0 -> internal 1 -> external
-- st,adc-freq : ADC Clock speed
- 0 -> 1.625 MHz 2 || 3 -> 6.5 MHz
- 1 -> 3.25 MHz
- st,ave-ctrl : Sample average control
0 -> 1 sample
1 -> 2 samples
@@ -40,17 +28,29 @@ Optional properties:
0 -> 20 mA (typical 35mA max)
1 -> 50 mA (typical 80 mA max)

+Optional properties common with MFD (deprecated):
+ - st,sample-time : ADC conversion time in number of clock.
+ 0 -> 36 clocks 4 -> 80 clocks (recommended)
+ 1 -> 44 clocks 5 -> 96 clocks
+ 2 -> 56 clocks 6 -> 124 clocks
+ 3 -> 64 clocks
+ - st,mod-12b : ADC Bit mode
+ 0 -> 10bit ADC 1 -> 12bit ADC
+ - st,ref-sel : ADC reference source
+ 0 -> internal 1 -> external
+ - st,adc-freq : ADC Clock speed
+ 0 -> 1.625 MHz 2 || 3 -> 6.5 MHz
+ 1 -> 3.25 MHz
+
Node name must be stmpe_touchscreen and should be child node of stmpe node to
which it belongs.

+Note that common ADC settings of stmpe_touchscreen will take precedence.
+
Example:

stmpe_touchscreen {
compatible = "st,stmpe-ts";
- st,sample-time = <4>;
- st,mod-12b = <1>;
- st,ref-sel = <0>;
- st,adc-freq = <1>;
st,ave-ctrl = <1>;
st,touch-det-delay = <2>;
st,settling = <2>;
diff --git a/Documentation/devicetree/bindings/mfd/stmpe.txt b/Documentation/devicetree/bindings/mfd/stmpe.txt
index a46e7177195d..d4408a417193 100644
--- a/Documentation/devicetree/bindings/mfd/stmpe.txt
+++ b/Documentation/devicetree/bindings/mfd/stmpe.txt
@@ -14,6 +14,20 @@ Optional properties:
- st,autosleep-timeout : Valid entries (ms); 4, 16, 32, 64, 128, 256, 512 and 1024
- irq-gpio : If present, which GPIO to use for event IRQ

+Optional properties for devices with touch and ADC (STMPE811|STMPE610):
+ - st,sample-time : ADC conversion time in number of clock.
+ 0 -> 36 clocks 4 -> 80 clocks (recommended)
+ 1 -> 44 clocks 5 -> 96 clocks
+ 2 -> 56 clocks 6 -> 124 clocks
+ 3 -> 64 clocks
+ - st,mod-12b : ADC Bit mode
+ 0 -> 10bit ADC 1 -> 12bit ADC
+ - st,ref-sel : ADC reference source
+ 0 -> internal 1 -> external
+ - st,adc-freq : ADC Clock speed
+ 0 -> 1.625 MHz 2 || 3 -> 6.5 MHz
+ 1 -> 3.25 MHz
+
Example:

stmpe1601: stmpe1601@40 {
--
2.19.2
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