1 ================================== 1 ==================================
2 Regulator Machine Driver Interface 2 Regulator Machine Driver Interface
3 ================================== 3 ==================================
4 4
5 The regulator machine driver interface is inte 5 The regulator machine driver interface is intended for board/machine specific
6 initialisation code to configure the regulator 6 initialisation code to configure the regulator subsystem.
7 7
8 Consider the following machine:: 8 Consider the following machine::
9 9
10 Regulator-1 -+-> Regulator-2 --> [Consumer A 10 Regulator-1 -+-> Regulator-2 --> [Consumer A @ 1.8 - 2.0V]
11 | 11 |
12 +-> [Consumer B @ 3.3V] 12 +-> [Consumer B @ 3.3V]
13 13
14 The drivers for consumers A & B must be mapped 14 The drivers for consumers A & B must be mapped to the correct regulator in
15 order to control their power supplies. This ma 15 order to control their power supplies. This mapping can be achieved in machine
16 initialisation code by creating a struct regul 16 initialisation code by creating a struct regulator_consumer_supply for
17 each regulator:: 17 each regulator::
18 18
19 struct regulator_consumer_supply { 19 struct regulator_consumer_supply {
20 const char *dev_name; /* consumer de 20 const char *dev_name; /* consumer dev_name() */
21 const char *supply; /* consumer su 21 const char *supply; /* consumer supply - e.g. "vcc" */
22 }; 22 };
23 23
24 e.g. for the machine above:: 24 e.g. for the machine above::
25 25
26 static struct regulator_consumer_supply regu 26 static struct regulator_consumer_supply regulator1_consumers[] = {
27 REGULATOR_SUPPLY("Vcc", "consumer B"), 27 REGULATOR_SUPPLY("Vcc", "consumer B"),
28 }; 28 };
29 29
30 static struct regulator_consumer_supply regu 30 static struct regulator_consumer_supply regulator2_consumers[] = {
31 REGULATOR_SUPPLY("Vcc", "consumer A"), 31 REGULATOR_SUPPLY("Vcc", "consumer A"),
32 }; 32 };
33 33
34 This maps Regulator-1 to the 'Vcc' supply for 34 This maps Regulator-1 to the 'Vcc' supply for Consumer B and maps Regulator-2
35 to the 'Vcc' supply for Consumer A. 35 to the 'Vcc' supply for Consumer A.
36 36
37 Constraints can now be registered by defining 37 Constraints can now be registered by defining a struct regulator_init_data
38 for each regulator power domain. This structur 38 for each regulator power domain. This structure also maps the consumers
39 to their supply regulators:: 39 to their supply regulators::
40 40
41 static struct regulator_init_data regulator1 41 static struct regulator_init_data regulator1_data = {
42 .constraints = { 42 .constraints = {
43 .name = "Regulator-1", 43 .name = "Regulator-1",
44 .min_uV = 3300000, 44 .min_uV = 3300000,
45 .max_uV = 3300000, 45 .max_uV = 3300000,
46 .valid_modes_mask = REGULATOR_ 46 .valid_modes_mask = REGULATOR_MODE_NORMAL,
47 }, 47 },
48 .num_consumer_supplies = ARRAY_SIZE(re 48 .num_consumer_supplies = ARRAY_SIZE(regulator1_consumers),
49 .consumer_supplies = regulator1_consum 49 .consumer_supplies = regulator1_consumers,
50 }; 50 };
51 51
52 The name field should be set to something that 52 The name field should be set to something that is usefully descriptive
53 for the board for configuration of supplies fo 53 for the board for configuration of supplies for other regulators and
54 for use in logging and other diagnostic output 54 for use in logging and other diagnostic output. Normally the name
55 used for the supply rail in the schematic is a 55 used for the supply rail in the schematic is a good choice. If no
56 name is provided then the subsystem will choos 56 name is provided then the subsystem will choose one.
57 57
58 Regulator-1 supplies power to Regulator-2. Thi 58 Regulator-1 supplies power to Regulator-2. This relationship must be registered
59 with the core so that Regulator-1 is also enab 59 with the core so that Regulator-1 is also enabled when Consumer A enables its
60 supply (Regulator-2). The supply regulator is 60 supply (Regulator-2). The supply regulator is set by the supply_regulator
61 field below and co:: 61 field below and co::
62 62
63 static struct regulator_init_data regulator2 63 static struct regulator_init_data regulator2_data = {
64 .supply_regulator = "Regulator-1", 64 .supply_regulator = "Regulator-1",
65 .constraints = { 65 .constraints = {
66 .min_uV = 1800000, 66 .min_uV = 1800000,
67 .max_uV = 2000000, 67 .max_uV = 2000000,
68 .valid_ops_mask = REGULATOR_CH 68 .valid_ops_mask = REGULATOR_CHANGE_VOLTAGE,
69 .valid_modes_mask = REGULATOR_ 69 .valid_modes_mask = REGULATOR_MODE_NORMAL,
70 }, 70 },
71 .num_consumer_supplies = ARRAY_SIZE(re 71 .num_consumer_supplies = ARRAY_SIZE(regulator2_consumers),
72 .consumer_supplies = regulator2_consum 72 .consumer_supplies = regulator2_consumers,
73 }; 73 };
74 74
75 Finally the regulator devices must be register 75 Finally the regulator devices must be registered in the usual manner::
76 76
77 static struct platform_device regulator_devi 77 static struct platform_device regulator_devices[] = {
78 { 78 {
79 .name = "regulator", 79 .name = "regulator",
80 .id = DCDC_1, 80 .id = DCDC_1,
81 .dev = { 81 .dev = {
82 .platform_data = ®u 82 .platform_data = ®ulator1_data,
83 }, 83 },
84 }, 84 },
85 { 85 {
86 .name = "regulator", 86 .name = "regulator",
87 .id = DCDC_2, 87 .id = DCDC_2,
88 .dev = { 88 .dev = {
89 .platform_data = ®u 89 .platform_data = ®ulator2_data,
90 }, 90 },
91 }, 91 },
92 }; 92 };
93 /* register regulator 1 device */ 93 /* register regulator 1 device */
94 platform_device_register(®ulator_devices[ 94 platform_device_register(®ulator_devices[0]);
95 95
96 /* register regulator 2 device */ 96 /* register regulator 2 device */
97 platform_device_register(®ulator_devices[ 97 platform_device_register(®ulator_devices[1]);
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