1 # SPDX-License-Identifier: GPL-2.0-only
2 %YAML 1.2
3 ---
4 $id: http://devicetree.org/schemas/iio/adc/qcom,spmi-vadc.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
6
7 title: Qualcomm's SPMI PMIC ADC
8
9 maintainers:
10 - Andy Gross <agross@kernel.org>
11 - Bjorn Andersson <bjorn.andersson@linaro.org>
12
13 description: |
14 SPMI PMIC voltage ADC (VADC) provides interface to clients to read
15 voltage. The VADC is a 15-bit sigma-delta ADC.
16 SPMI PMIC5/PMIC7 voltage ADC (ADC) provides interface to clients to read
17 voltage. The VADC is a 16-bit sigma-delta ADC.
18
19 properties:
20 compatible:
21 oneOf:
22 - items:
23 - const: qcom,pms405-adc
24 - const: qcom,spmi-adc-rev2
25 - enum:
26 - qcom,spmi-vadc
27 - qcom,spmi-adc5
28 - qcom,spmi-adc-rev2
29 - qcom,spmi-adc7
30
31 reg:
32 description: VADC base address in the SPMI PMIC register map
33 maxItems: 1
34
35 '#address-cells':
36 const: 1
37
38 '#size-cells':
39 const: 0
40
41 '#io-channel-cells':
42 const: 1
43
44 interrupts:
45 maxItems: 1
46 description:
47 End of conversion interrupt.
48
49 required:
50 - compatible
51 - reg
52 - '#address-cells'
53 - '#size-cells'
54 - '#io-channel-cells'
55
56 patternProperties:
57 "^channel@[0-9a-f]+$":
58 type: object
59 additionalProperties: false
60 description: |
61 Represents the external channels which are connected to the ADC.
62 For compatible property "qcom,spmi-vadc" following channels, also known as
63 reference point channels, are used for result calibration and their channel
64 configuration nodes should be defined:
65 VADC_REF_625MV and/or VADC_SPARE1(based on PMIC version) VADC_REF_1250MV,
66 VADC_GND_REF and VADC_VDD_VADC.
67
68 properties:
69 reg:
70 maxItems: 1
71 description: |
72 ADC channel number.
73 See include/dt-bindings/iio/qcom,spmi-vadc.h
74 For PMIC7 ADC, the channel numbers are specified separately per PMIC
75 in the PMIC-specific files in include/dt-bindings/iio/.
76
77 label:
78 description: |
79 ADC input of the platform as seen in the schematics.
80 For thermistor inputs connected to generic AMUX or GPIO inputs
81 these can vary across platform for the same pins. Hence select
82 the platform schematics name for this channel.
83
84 qcom,decimation:
85 $ref: /schemas/types.yaml#/definitions/uint32
86 description: |
87 This parameter is used to decrease ADC sampling rate.
88 Quicker measurements can be made by reducing decimation ratio.
89
90 qcom,pre-scaling:
91 description: |
92 Used for scaling the channel input signal before the signal is
93 fed to VADC. The configuration for this node is to know the
94 pre-determined ratio and use it for post scaling. It is a pair of
95 integers, denoting the numerator and denominator of the fraction by which
96 input signal is multiplied. For example, <1 3> indicates the signal is scaled
97 down to 1/3 of its value before ADC measurement.
98 If property is not found default value depending on chip will be used.
99 $ref: /schemas/types.yaml#/definitions/uint32-array
100 oneOf:
101 - items:
102 - const: 1
103 - enum: [ 1, 3, 4, 6, 20, 8, 10, 16 ]
104 - items:
105 - const: 10
106 - const: 81
107
108 qcom,ratiometric:
109 description: |
110 Channel calibration type.
111 - For compatible property "qcom,spmi-vadc", if this property is
112 specified VADC will use the VDD reference (1.8V) and GND for
113 channel calibration. If property is not found, channel will be
114 calibrated with 0.625V and 1.25V reference channels, also
115 known as absolute calibration.
116 - For compatible property "qcom,spmi-adc5", "qcom,spmi-adc7" and
117 "qcom,spmi-adc-rev2", if this property is specified VADC will use
118 the VDD reference (1.875V) and GND for channel calibration. If
119 property is not found, channel will be calibrated with 0V and 1.25V
120 reference channels, also known as absolute calibration.
121 type: boolean
122
123 qcom,hw-settle-time:
124 $ref: /schemas/types.yaml#/definitions/uint32
125 description: |
126 Time between AMUX getting configured and the ADC starting
127 conversion. The 'hw_settle_time' is an index used from valid values
128 and programmed in hardware to achieve the hardware settling delay.
129
130 qcom,avg-samples:
131 $ref: /schemas/types.yaml#/definitions/uint32
132 description: |
133 Number of samples to be used for measurement.
134 Averaging provides the option to obtain a single measurement
135 from the ADC that is an average of multiple samples. The value
136 selected is 2^(value).
137
138 required:
139 - reg
140
141 allOf:
142 - if:
143 properties:
144 compatible:
145 contains:
146 const: qcom,spmi-vadc
147
148 then:
149 patternProperties:
150 "^channel@[0-9a-f]+$":
151 properties:
152 qcom,decimation:
153 enum: [ 512, 1024, 2048, 4096 ]
154 default: 512
155
156 qcom,hw-settle-time:
157 enum: [ 0, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1, 2,
158 4, 6, 8, 10 ]
159 default: 0
160
161 qcom,avg-samples:
162 enum: [ 1, 2, 4, 8, 16, 32, 64, 128, 256, 512 ]
163 default: 1
164
165 - if:
166 properties:
167 compatible:
168 contains:
169 const: qcom,spmi-adc-rev2
170
171 then:
172 patternProperties:
173 "^channel@[0-9a-f]+$":
174 properties:
175 qcom,decimation:
176 enum: [ 256, 512, 1024 ]
177 default: 1024
178
179 qcom,hw-settle-time:
180 enum: [ 0, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1, 2,
181 4, 6, 8, 10 ]
182 default: 0
183
184 qcom,avg-samples:
185 enum: [ 1, 2, 4, 8, 16 ]
186 default: 1
187
188 - if:
189 properties:
190 compatible:
191 contains:
192 const: qcom,spmi-adc5
193
194 then:
195 patternProperties:
196 "^channel@[0-9a-f]+$":
197 properties:
198 qcom,decimation:
199 enum: [ 250, 420, 840 ]
200 default: 840
201
202 qcom,hw-settle-time:
203 enum: [ 15, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1, 2,
204 4, 6, 8, 10, 16, 32, 64, 128 ]
205 default: 15
206
207 qcom,avg-samples:
208 enum: [ 1, 2, 4, 8, 16 ]
209 default: 1
210
211 - if:
212 properties:
213 compatible:
214 contains:
215 const: qcom,spmi-adc7
216
217 then:
218 patternProperties:
219 "^channel@[0-9a-f]+$":
220 properties:
221 qcom,decimation:
222 enum: [ 85, 340, 1360 ]
223 default: 1360
224
225 qcom,hw-settle-time:
226 enum: [ 15, 100, 200, 300, 400, 500, 600, 700, 1000, 2000, 4000,
227 8000, 16000, 32000, 64000, 128000 ]
228 default: 15
229
230 qcom,avg-samples:
231 enum: [ 1, 2, 4, 8, 16 ]
232 default: 1
233
234 additionalProperties: false
235
236 examples:
237 - |
238 pmic {
239 #address-cells = <1>;
240 #size-cells = <0>;
241
242 adc@3100 {
243 compatible = "qcom,spmi-vadc";
244 reg = <0x3100>;
245 interrupts = <0x0 0x31 0x0 0x1>;
246 #address-cells = <1>;
247 #size-cells = <0>;
248 #io-channel-cells = <1>;
249
250 /* Channel node */
251 channel@39 {
252 reg = <0x39>;
253 qcom,decimation = <512>;
254 qcom,ratiometric;
255 qcom,hw-settle-time = <200>;
256 qcom,avg-samples = <1>;
257 qcom,pre-scaling = <1 3>;
258 };
259
260 channel@9 {
261 reg = <0x9>;
262 };
263
264 channel@a {
265 reg = <0xa>;
266 };
267
268 channel@e {
269 reg = <0xe>;
270 };
271
272 channel@f {
273 reg = <0xf>;
274 };
275 };
276 };
277
278 - |
279 #include <dt-bindings/iio/qcom,spmi-adc7-pmk8350.h>
280 #include <dt-bindings/iio/qcom,spmi-adc7-pm8350.h>
281 #include <dt-bindings/interrupt-controller/irq.h>
282
283 pmic {
284 #address-cells = <1>;
285 #size-cells = <0>;
286
287 adc@3100 {
288 reg = <0x3100>;
289 compatible = "qcom,spmi-adc7";
290 #address-cells = <1>;
291 #size-cells = <0>;
292 #io-channel-cells = <1>;
293
294 /* Other properties are omitted */
295 channel@44 {
296 reg = <PMK8350_ADC7_AMUX_THM1_100K_PU>;
297 qcom,ratiometric;
298 qcom,hw-settle-time = <200>;
299 label = "xo_therm";
300 };
301
302 channel@47 {
303 reg = <PM8350_ADC7_AMUX_THM4_100K_PU(1)>;
304 qcom,ratiometric;
305 qcom,hw-settle-time = <200>;
306 label = "conn_therm";
307 };
308 };
309 };
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