1 # SPDX-License-Identifier: (GPL-2.0-only OR BS 1 # SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 %YAML 1.2 2 %YAML 1.2
3 --- 3 ---
4 $id: http://devicetree.org/schemas/i3c/i3c.yam 4 $id: http://devicetree.org/schemas/i3c/i3c.yaml#
5 $schema: http://devicetree.org/meta-schemas/co 5 $schema: http://devicetree.org/meta-schemas/core.yaml#
6 6
7 title: I3C bus 7 title: I3C bus
8 8
9 maintainers: 9 maintainers:
10 - Alexandre Belloni <alexandre.belloni@bootli 10 - Alexandre Belloni <alexandre.belloni@bootlin.com>
11 - Miquel Raynal <miquel.raynal@bootlin.com> 11 - Miquel Raynal <miquel.raynal@bootlin.com>
12 12
13 description: | 13 description: |
14 I3C busses can be described with a node for 14 I3C busses can be described with a node for the primary I3C controller device
15 and a set of child nodes for each I2C or I3C 15 and a set of child nodes for each I2C or I3C slave on the bus. Each of them
16 may, during the life of the bus, request mas 16 may, during the life of the bus, request mastership.
17 17
18 properties: 18 properties:
19 $nodename: 19 $nodename:
20 pattern: "^i3c@[0-9a-f]+$" 20 pattern: "^i3c@[0-9a-f]+$"
21 21
22 "#address-cells": 22 "#address-cells":
23 const: 3 23 const: 3
24 description: | 24 description: |
25 Each I2C device connected to the bus sho 25 Each I2C device connected to the bus should be described in a subnode.
26 26
27 All I3C devices are supposed to support 27 All I3C devices are supposed to support DAA (Dynamic Address Assignment),
28 and are thus discoverable. So, by defaul 28 and are thus discoverable. So, by default, I3C devices do not have to be
29 described in the device tree. This being 29 described in the device tree. This being said, one might want to attach
30 extra resources to these devices, and th 30 extra resources to these devices, and those resources may have to be
31 described in the device tree, which in t 31 described in the device tree, which in turn means we have to describe
32 I3C devices. 32 I3C devices.
33 33
34 Another use case for describing an I3C d 34 Another use case for describing an I3C device in the device tree is when
35 this I3C device has a static I2C address 35 this I3C device has a static I2C address and we want to assign it a
36 specific I3C dynamic address before the 36 specific I3C dynamic address before the DAA takes place (so that other
37 devices on the bus can't take this dynam 37 devices on the bus can't take this dynamic address).
38 38
39 "#size-cells": 39 "#size-cells":
40 const: 0 40 const: 0
41 41
42 i3c-scl-hz: 42 i3c-scl-hz:
43 description: | 43 description: |
44 Frequency of the SCL signal used for I3C 44 Frequency of the SCL signal used for I3C transfers. When undefined, the
45 default value should be 12.5MHz. 45 default value should be 12.5MHz.
46 46
47 May not be supported by all controllers. 47 May not be supported by all controllers.
48 48
49 i2c-scl-hz: 49 i2c-scl-hz:
50 description: | 50 description: |
51 Frequency of the SCL signal used for I2C 51 Frequency of the SCL signal used for I2C transfers. When undefined, the
52 default should be to look at LVR (Legacy 52 default should be to look at LVR (Legacy Virtual Register) values of
53 I2C devices described in the device tree 53 I2C devices described in the device tree to determine the maximum I2C
54 frequency. 54 frequency.
55 55
56 May not be supported by all controllers. 56 May not be supported by all controllers.
57 57
58 mctp-controller: 58 mctp-controller:
59 type: boolean 59 type: boolean
60 description: | 60 description: |
61 Indicates that the system is accessible 61 Indicates that the system is accessible via this bus as an endpoint for
62 MCTP over I3C transport. 62 MCTP over I3C transport.
63 63
64 required: 64 required:
65 - "#address-cells" 65 - "#address-cells"
66 - "#size-cells" 66 - "#size-cells"
67 67
68 patternProperties: 68 patternProperties:
69 "@[0-9a-f]+$": 69 "@[0-9a-f]+$":
70 type: object 70 type: object
71 description: | 71 description: |
72 I2C child, should be named: <device-type> 72 I2C child, should be named: <device-type>@<i2c-address>
73 73
74 All properties described in dtschema sch 74 All properties described in dtschema schemas/i2c/i2c-controller.yaml
75 are valid here, except the reg property 75 are valid here, except the reg property whose content is changed.
76 76
77 properties: 77 properties:
78 compatible: 78 compatible:
79 description: 79 description:
80 Compatible of the I2C device. 80 Compatible of the I2C device.
81 81
82 reg: 82 reg:
83 items: 83 items:
84 - items: 84 - items:
85 - description: | 85 - description: |
86 I2C address. 10 bit addressi 86 I2C address. 10 bit addressing is not supported. Devices with
87 10-bit address can't be prop 87 10-bit address can't be properly passed through DEFSLVS
88 command. 88 command.
89 minimum: 0 89 minimum: 0
90 maximum: 0x7f 90 maximum: 0x7f
91 - const: 0 91 - const: 0
92 - description: | 92 - description: |
93 Shall encode the I3C LVR (Le 93 Shall encode the I3C LVR (Legacy Virtual Register):
94 See include/dt-bindings/i3c/ <<
95 bit[31:8]: unused/ignored 94 bit[31:8]: unused/ignored
96 bit[7:5]: I2C device index 95 bit[7:5]: I2C device index. Possible values:
97 * 0: I2C device has a 50 96 * 0: I2C device has a 50 ns spike filter
98 * 1: I2C device does not 97 * 1: I2C device does not have a 50 ns spike filter but
99 supports high frequ 98 supports high frequency on SCL
100 * 2: I2C device does not 99 * 2: I2C device does not have a 50 ns spike filter and is
101 not tolerant to hig 100 not tolerant to high frequencies
102 * 3-7: reserved 101 * 3-7: reserved
103 bit[4]: tell whether the d 102 bit[4]: tell whether the device operates in FM (Fast Mode)
104 or FM+ mode: 103 or FM+ mode:
105 * 0: FM+ mode 104 * 0: FM+ mode
106 * 1: FM mode 105 * 1: FM mode
107 bit[3:0]: device type 106 bit[3:0]: device type
108 * 0-15: reserved 107 * 0-15: reserved
109 108
110 required: 109 required:
111 - compatible 110 - compatible
112 - reg 111 - reg
113 112
114 "@[0-9a-f]+,[0-9a-f]+$": 113 "@[0-9a-f]+,[0-9a-f]+$":
115 type: object 114 type: object
116 description: | 115 description: |
117 I3C child, should be named: <device-type> 116 I3C child, should be named: <device-type>@<static-i2c-address>,<i3c-pid>
118 117
119 properties: 118 properties:
120 reg: 119 reg:
121 items: 120 items:
122 - items: 121 - items:
123 - description: | 122 - description: |
124 Encodes the static I2C addre 123 Encodes the static I2C address. Should be 0 if the device does
125 not have one (0 is not a val 124 not have one (0 is not a valid I2C address).
126 minimum: 0 125 minimum: 0
127 maximum: 0x7f 126 maximum: 0x7f
128 - description: | 127 - description: |
129 First half of the Provisione 128 First half of the Provisioned ID (following the PID
130 definition provided by the I 129 definition provided by the I3C specification).
131 130
132 Contains the manufacturer ID 131 Contains the manufacturer ID left-shifted by 1.
133 - description: | 132 - description: |
134 Second half of the Provision 133 Second half of the Provisioned ID (following the PID
135 definition provided by the I 134 definition provided by the I3C specification).
136 135
137 Contains the ORing of the pa 136 Contains the ORing of the part ID left-shifted by 16,
138 the instance ID left-shifted 137 the instance ID left-shifted by 12 and extra information.
139 138
140 assigned-address: 139 assigned-address:
141 $ref: /schemas/types.yaml#/definitions 140 $ref: /schemas/types.yaml#/definitions/uint32
142 minimum: 0x1 141 minimum: 0x1
143 maximum: 0xff 142 maximum: 0xff
144 description: | 143 description: |
145 Dynamic address to be assigned to th 144 Dynamic address to be assigned to this device. In case static address is
146 present (first cell of the reg prope 145 present (first cell of the reg property != 0), this address is assigned
147 through SETDASA. If static address i 146 through SETDASA. If static address is not present, this address is assigned
148 through SETNEWDA after assigning a t 147 through SETNEWDA after assigning a temporary address via ENTDAA.
149 148
150 required: 149 required:
151 - reg 150 - reg
152 151
153 additionalProperties: true 152 additionalProperties: true
154 153
155 examples: 154 examples:
156 - | 155 - |
157 #include <dt-bindings/i3c/i3c.h> <<
158 <<
159 i3c@d040000 { 156 i3c@d040000 {
160 compatible = "cdns,i3c-master"; 157 compatible = "cdns,i3c-master";
161 clocks = <&coreclock>, <&i3csysclock>; 158 clocks = <&coreclock>, <&i3csysclock>;
162 clock-names = "pclk", "sysclk"; 159 clock-names = "pclk", "sysclk";
163 interrupts = <3 0>; 160 interrupts = <3 0>;
164 reg = <0x0d040000 0x1000>; 161 reg = <0x0d040000 0x1000>;
165 #address-cells = <3>; 162 #address-cells = <3>;
166 #size-cells = <0>; 163 #size-cells = <0>;
167 i2c-scl-hz = <100000>; 164 i2c-scl-hz = <100000>;
168 165
169 /* I2C device. */ 166 /* I2C device. */
170 eeprom@57 { 167 eeprom@57 {
171 compatible = "atmel,24c01"; 168 compatible = "atmel,24c01";
172 reg = <0x57 0x0 (I2C_FM | I2C_FILT !! 169 reg = <0x57 0x0 0x10>;
173 pagesize = <0x8>; 170 pagesize = <0x8>;
174 }; 171 };
175 172
176 /* I3C device with a static I2C addres 173 /* I3C device with a static I2C address and assigned address. */
177 thermal_sensor: sensor@68,39200144004 174 thermal_sensor: sensor@68,39200144004 {
178 reg = <0x68 0x392 0x144004>; 175 reg = <0x68 0x392 0x144004>;
179 assigned-address = <0xa>; 176 assigned-address = <0xa>;
180 }; 177 };
181 178
182 /* I3C device with only assigned addre 179 /* I3C device with only assigned address. */
183 pressure_sensor: sensor@0,39200124004 180 pressure_sensor: sensor@0,39200124004 {
184 reg = <0x0 0x392 0x124000>; 181 reg = <0x0 0x392 0x124000>;
185 assigned-address = <0xc>; 182 assigned-address = <0xc>;
186 }; 183 };
187 184
188 /* 185 /*
189 * I3C device without a static I2C add 186 * I3C device without a static I2C address but requiring
190 * resources described in the DT. 187 * resources described in the DT.
191 */ 188 */
192 sensor@0,39200154004 { 189 sensor@0,39200154004 {
193 reg = <0x0 0x392 0x154004>; 190 reg = <0x0 0x392 0x154004>;
194 clocks = <&clock_provider 0>; 191 clocks = <&clock_provider 0>;
195 }; 192 };
196 }; 193 };
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